HP Commercial and Industrial Large-Format Printing Technologies

Transcription

1 HP Commercial and Industrial Large-Format Printing Technologies Inkjet Ink... 2 Basics... 2 Durability and Display Permanence... 3 Color Writing Systems ink System ink System ink System... 5 Blacks and Grays... 5 More Colors... 6 White Ink... 6 Colorants... 6 Ink Vehicles... 7 Aqueous Inks... 8 HP Vivera Inks... 9 HP Vivera Pigment Inks... 9 HP Latex Inks Curing HP Latex Inks HP Scitex WB300 Supreme Inks Solvent-based Inks UV-curable Inks HP Large-format Printing Materials Surface Treatments HP Surface Treatment Technology Coated Media Porous Coatings Swellable Coatings Absorbent Media Nonabsorbent Media Inkjet Printhead Technologies HP Thermal Inkjet Printheads with Scalable Printing Technology HP Designjet Z- and T-series Printers HP Designjet L25500 and HP Designjet L65500 Printers with HP Latex Inks Piezoelectric Printheads HP Scitex X2 Piezo Printheads Summary For more information... 26

2 HP offers commercial and industrial large-format inkjet printing solutions based on aqueous, solvent, and UV-curable inks in flexible (cut-sheet and roll-to-roll) and flatbed (rigid) configurations. HP printers in large, wide, and super-wide formats span the range of commercial and industrial printing applications including digital fine art, indoor and outdoor display graphics, point of purchase advertising, billboards and signage, exhibitions, short-run product packaging, and vehicle and building wraps. For each application, the choice of printer, ink, and print medium depends on print size, production volumes, production cost, and other requirements including print durability, display permanence, and image quality. You should consult with an HP Commercial and Industrial Printing Sales Engineer to select the HP solution that best meets your business needs. This document can help you understand HP s portfolio of inkjet technologies to prepare you to make the right choice that will produce results meeting your needs and expectations. The ink technologies used in HP Designjet and HP Scitex printers are summarized in the table below. 1 Flexible Rigid Inkjet Ink Aqueous Inks Solvent Inks UV-curable Inks HP Designjet 8000s, 9000s, 10000s HP Designjet T610,T620, T770, T1100, T1200, Z2100, Z3200, Z6100, L25500, L65500 HP Scitex FB6700 HP Scitex TJ8350, XL1200, XL1500 HP Designjet H35100/35500, H45100/45500 HP Scitex FB950, FB6100/6050, TJ8550, XP2100, XP2300, XP2750, XP5100, XP5300 HP Designjet H35100/35500, H45100/45500 HP Scitex FB950, FB6100/6050, FB7500, XP2750 HP printing solutions have built a reputation for performance, quality, dependability, and value using Original HP inks. The physical, chemical, and color properties of inkjet inks affect every part of an inkjet printing system. Reliable printer performance and consistent output quality depend on the ink. Basics Inkjet inks are highly-engineered materials that must be carefully formulated, then manufactured under rigorous quality control, and finally exhaustively tested to deliver consistent and reliable performance. Physical properties of an ink are critical to the design and operation of the ink delivery system and printheads. For example, color accuracy, image quality, and freedom from visible print defects depend on precise control of ink drop volume and dot placement on the print medium. Drop ejection is strongly affected by ink viscosity and surface tension. These ink properties have consistent behaviors in Original HP inks that allow the printer to meet speed-quality specifications and operate reliably over its specified environmental range. The selection of ink components and their purity is essential to reliable printer operation. Contamination by certain metal ions at levels of only a few parts per million can cause pigments to precipitate out of 1 Some products require optional conversion kits to print both rigid and flexible media. See HP product data sheets for complete details or visit 2

3 the ink. This can clog ink supply tubes and the microscopic ink passages inside printheads leading to printer failure and the expense of downtime and replacing parts. Inks touch plastic, metal, adhesive, and elastic materials that are used in the ink delivery system, printheads, and printhead service stations. Every component of the ink and printer materials coming into contact with ink must be selected and designed to work together. Adverse ink-material reactions can cause corrosion of metal parts and can soften or dissolve plastics, adhesives, and elastomers. Contamination by residues from these reactions may require early printhead replacement to maintain printer performance and output quality. During the development of HP commercial and industrial printing solutions, HP engineers perform extensive material compatibility and performance testing with Original HP inks under standby, normal, and extreme operational conditions over a range of temperature and humidity. Test procedures are based on HP s proprietary knowledge of what s in the ink, what s in the printer, and specific performance requirements for each component of the printing system. Some issues may appear early in these tests, but others may appear only after months of storage and operation and under special circumstances. If a problem is found during product development, changing either a printer component or the inks or both requires new qualification tests. HP s commitment to providing reliable commercial and industrial printing solutions involves a significant investment in experienced test and development engineers, test equipment and facilities, and time. HP s product development process characterizes and optimizes printers, ink, and large-format printing materials as a system. HP conducts comprehensive print quality testing over a range of environmental conditions. Print durability and display permanence are evaluated according to HP, ISO, ASTM, and Wilhelm Imaging Research protocols. Working together, Original HP inks and HP large-format printing materials deliver dependable print quality, color accuracy, durability, and display permanence meeting customers expectations without costly trial-and-error. Third-party ink suppliers generally do not have access to the material specifications and performance requirements for all parts of an HP printing system that are affected by the ink. Without HP s proprietary system knowledge and resources, performance qualification cannot be as thorough and complete as with an HP-branded solution. While third-party inks may promise lower cost per liter of ink, ink represents only a fraction of the total cost of print production. Users should assess all the costs involved and understand how their profit can be reduced by lower productivity, printer downtime and repairs, and waste from print optimization by trial and error. The dependability of a printing solution developed, tested, and backed by HP should be an important consideration in the selection of inks and large-format printing materials. Durability and Display Permanence Durability and display permanence are key attributes for prints displayed both indoors and outdoors. Durability generally relates to how well the colorant binds to the print medium and the resistance of the print medium to deterioration under conditions of use. Colorant durability can be characterized by the resistance of a printed image to water and to rubbing, abrasion, and smearing when the print is cleaned with wipes and common chemicals (especially important for vehicle graphics). Durability also considers resistance of the image to cracking as the print is bent, folded, or stretched. When durability alone is specified, degradation of a print s optical and mechanical properties may be considered together under conditions specified by standards such as ASTM D Display permanence, sometimes called fade resistance or lightfastness, characterizes the change in color and optical density of the image under exposure to light, particularly sunlight and sources of ultraviolet (UV) light. Display permanence measures the time required for colors to change by a specified amount under standardized conditions such as display in-window, outdoors, indoors behind glass away from direct sunlight, etc. These are reference conditions used for comparative purposes between ink technologies and between specific inks on specific media within a technology. Display permanence is often specified with and without lamination for prints displayed in direct sunlight inwindow or outdoors. 3

4 Display permanence claims are based on predictions from standardized, accelerated tests following HP, ISO, ASTM, and Wilhelm Imaging Research protocols. These claims are intended to give guidance for choosing an ink technology and print medium selection. Display permanence depends on actual display conditions for the print, and the amount of UV light in the display environment has a predominant effect on fading. While longer display permanence is generally considered a virtue, economical print production dictates that the useful life for the print in its actual display environment be carefully factored into the choice of ink technology and printing material. Realistically, not every print needs to last 2-3 years outdoors or more than 200 years on indoor display. For more information on how the choice of ink technology and printing material affects display permanence, visit Color Writing Systems The hardware for an inkjet writing system involves the inks and printheads that produce an image on the print medium, 2 which can be paper, vinyl, textiles, banner materials, cardboard, plastics, and other materials. When ink chemistry requires curing inside the printer, the writing system also includes components for the curing process. For example, UV-curable inks require high-intensity ultraviolet lamps to solidify the ink. HP Latex Inks require internal heat and forced air systems to evaporate volatile ink components and coalesce latex particles into a durable film. Both UV-curable inks and HP Latex Inks produce prints that are dry and ready to use out of the printer. Writing systems are typically described by the type and number of inks and the printhead technology. Inks are designated by their chemistry (aqueous, solvent, or UV-curable), their colorant (pigment or dye), and their color. For example, an 8-ink printer has an ink delivery system and printheads that accommodate eight inks. For application versatility, some 8-ink printers can be operated in 4-, 6-, or 8- ink modes depending on a print job s requirements for image quality, production rate, and economy. Writing systems for HP s commercial and industrial printers are based on either HP Thermal Inkjet printheads or piezo printheads. HP Thermal Inkjet printheads are used in HP Designjet printers with aqueous inks and HP Latex Inks. HP Scitex printers use piezo printheads for aqueous, solvent, and UVcurable inks. Inks are used in a subtractive color system where colored layers are applied over a white substrate. Combinations of different inks produce a desired color by absorbing (subtracting) certain wavelengths from the light reflected from the substrate. The color of the substrate and the color of the illuminant both affect the printed color. The primary colors in subtractive color printing are cyan, magenta, and yellow. Most colored inkjet inks are transparent 3, and this allows them to produce colors that are mixtures of these primaries (e.g., red = magenta + yellow, etc.) by printing one dot of ink on top of another: doton-dot. Original HP inks for commercial and industrial applications are designated by a one or two letter system as shown in the table below. Following industry practice, K represents black ink. HP uses G for gray and Gn for green inks. C: cyan lc: light cyan M: magenta lm: light magenta Y: yellow ly: light yellow G: gray lg: light gray K: black lk: light black pk: photo black mk: matte black R: red Gn: green B: blue E: Gloss Enhancer W: white 2 This is the printing material, also called the substrate. The substrate is the material and surface on which the image is formed. 3 Except, typically, black and white inks. 4

5 3-ink System The simplest subtractive color system is a 3-ink system with cyan, magenta, and yellow inks. Properly combined, CMY inks can produce a wide range of colors including reds, greens, blues, black, and grays. A 3-color system works because the human vision is trichromatic: the eye contains color receptors sensitive to red, green, and blue light, and the sensation of full color is produced by combining these stimuli in the brain. The basic process for making color prints with conventional (silver halide) photography also uses only cyan, magenta, and yellow dyes. Producing a dark, neutral black and neutral grays by combinations of colored inks is the weakness of a CMY system. The human eye is very sensitive to grays with reddish or greenish hues, and this is an objectionable print quality defect in most applications. Even if the printer, ink, and print medium are calibrated to produce good blacks and grays under a specific light source, a different illuminant can produce a significant hue shift. For example, gray tones in prints balanced for display under incandescent illumination may appear greenish under some fluorescent lights. This effect is called metamerism. Visible hues in neutral tones can be produced from relative changes in print density between cyan, magenta, and yellow. This can come from changes in drop volume, missing nozzles, drop placement errors, and other factors. 4-ink System Adding black ink to CMY makes a 4-ink system (CMYK) that offers higher black saturation because black is printed directly. Better reproduction of dark neutral tones is achieved by printing dark grays and blacks with black ink, but light grays are normally printed with CMY inks to minimize image grain. Black ink is especially important when applications require sharp, dark, black text. 4-ink systems are particularly useful for applications such as billboards and building wraps where productivity and production costs are important considerations. In these cases, the printed image is generally viewed casually and from a distance of many meters so that image grain in highlights and midtones is not a critical image-quality issue. 6-ink System Adding light magenta and light cyan inks to CMYK makes a 6-ink system (C lc M lm Y K). Image grain is reduced by printing highlight colors and light grays with the light (lc and lm) inks. This is because dots printed with Y, lc, and lm inks have less contrast against the white background of the substrate than dots printed with C, M, and K. A 6-ink system allows more combinations of ink colors to be printed in each pixel. More directlyprintable colors give smoother color transitions in an image. This reduces so-called tone breaks, which are undesirable artifacts in areas of the image where the hue or lightness changes slowly. 4 6-ink systems provide image quality that generally meets the needs of all but the most critical requirements. Blacks and Grays For photographic and fine art reproduction, the darkest printable black on a specific print medium is an important image-quality parameter. This is called the black-point and it is measured by black optical density (K OD ). L* 5 is the lightness parameter in the CIELab color space, and the minimum value of L*, L* min, is also used to measure black-point. The black-point depends both on the inks and the print medium. Because of specular reflection from the print surface, glossy photo papers deliver the highest value of K OD (lowest value of L* min ). Diffuse reflection from matte papers produces a lower K OD (higher L* min ). To achieve high black optical density, HP Designjet Z-series printers have two black inks installed: photo black (pk) ink for photo media with a glossy or satin finish, and matte black (mk) ink for matte media such as fine art papers. Used together on matte media, pk and mk deliver a higher K OD than pk alone. 4 For example, imagine a uniformly-colored sphere illuminated from the top with the bottom in shadow. Tone breaks, if present, appear as concentric bands of decreasing lightness in what should be a continuous variation from highlight to shadow. 5 This is pronounced L-star. 5

6 Using one or two gray inks significantly reduces image grain and metamerism and provides accurate reproduction of neutral gray tones from white to black. Printers with a single gray ink use a light or middle gray ink (lg or lk). For example, HP Designjet Z2100 and Z6100 Printers use lg in an 8-ink writing system: C lc M lm Y pk mk lg. Printers with two gray inks, such as the HP Designjet Z3200, 6 use light gray (lg) and gray (G) inks to produce true, neutral grays with low metamerism and for smooth, continuous tones and deep rich blacks. More Colors HP Scitex XL-series and FB6100/6050 Printers add a light yellow (ly) ink and a light black (lk) ink to the basic 6-ink system for an 8-ink writing system: C lc M lm Y ly K lk. The light yellow ink enhances the reproduction of natural colors and, with lk, reduces image grain in midtones and highlights compared to a 6-ink configuration. Adding red (R), green (Gn), and blue (B) inks extends the printing system s color gamut for these important colors, improves color accuracy and color consistency, and reduces color metamerism. HP Designjet Z3200 Printers use red, green, and blue inks along with a gloss enhancer (E) in a 12-ink writing system: lc M lm Y pk mk lg G R Gn B E. Light cyan and blue inks enable HP Designjet Z3200 Printers to reproduce a large color gamut for photographic applications without the need for a cyan (C) ink. HP Gloss Enhancer is a unique component of the writing system in the HP Designjet Z3200 Printer. Designed to meet the needs of professional photographers, HP Gloss Enhancer is used on photo media (except matte-finish papers) to produce images with uniform gloss from highlights to shadows across the color gamut, and it eliminates bronzing as an image quality issue. 7 HP Gloss Enhancer is colorless and used only where needed in white and low-density color areas. 8 White Ink In most applications, the hue and brightness of the printing material determines what appears white in a print. Effectively, the media surface is the white ink and determines the image white-point (L* max ). Because the ink layer is transparent (except for high density black areas), the color and lightness of the substrate affects the hue, saturation, and lightness of printed colors. Photo papers use a white substrate because a bright neutral white is critical to dynamic range and color accuracy in photographic prints. Other media, such as banner and textile materials, may be somewhat less bright (e.g., more gray) and have some color. This may not be objectionable or even noticeable in some signage or display applications. On colored media, white ink can produce a white spot color or a white substrate for subtractive color printing. White ink can be used to make opaque the backside of an image printed on transparent media. The HP Scitex FB6100/6050 Printers feature a White Ink Kit for this purpose. Colorants Inkjet inks consist of two major components: the colorant, which produces the image on the printing material, and the ink vehicle that carries the colorant to the print surface in precisely-controlled droplets. A colorant is a dye or a pigment and typically comprises less than 10% of the ink by weight. The remainder is the colorless ink vehicle composed of solvent(s), additives, and polymers. Some inks use a blend of dyes or pigments to get the desired color properties. Dyes may be added to pigment inks to increase chroma (i.e., colorfulness) for a larger color gamut. Between different writing systems, inks with the same common name, such as cyan, may be made with a different blend of colorants and at different concentrations. This is because the color properties 6 HP Designjet Z3200 Printers feature HP 73 Chromatic Red Ink and replace the HP Designjet Z3100 Printers. 7 In a print on glossy or semi-glossy media, bronzing appears as an unwanted metallic luster and changes in perceived density and tone. Due to the effect of surface texture, bronzing does not appear on matte media. 8 From the printer driver, the user has the option of controlling how HP Gloss Enhancer is applied. 6

7 of each ink in a system are chosen considering the number and color of other inks. For example, the cyan, magenta, and yellow inks in a 4-ink (CMYK) system may be different than those used in systems that have light colors (lc, lm) and gray inks because they are not constrained by the requirement to produce black. Dye-based inks use liquid or solid dyes that are dissolved in the ink vehicle. Dyes are individual molecules designed to absorb certain wavelengths of light. Dyes are small enough to penetrate any absorbent or coated print media, and dye-based inks offer a large color gamut with brilliant, saturated colors on photo papers. Limited outdoor permanence and durability of unlaminated prints made with dye-based inks restricts their use in commercial and industrial applications. For this reason, pigment inks are used in all of HP s commercial and industrial printing solutions except HP Designjet T-series technical graphics printers. Pigments are microscopic, colored particles that do not dissolve in the ink. A pigment particle may be coated with a polymer (resin) or have its surface chemically-treated to produce a stable suspension (dispersion) of pigments in the ink vehicle. Pigment particles used in inkjet inks typically range in size from 50 to 150 nanometers, depending on the material and color. During ink manufacture, pigment particle size and distribution must be carefully controlled to produce consistent physical and color imaging properties and to maintain a stable dispersion of pigments in the ink during shipping, storage, and use. The stability of the pigment dispersion is one important reason for having an Install Before date on ink cartridges. Over time, pigment particles may aggregate and precipitate out of the ink vehicle. This can clog the printer s ink delivery system and damage the printheads. After the Install Before date has passed, the pigment dispersion may no longer be effective. 9 HP s pigment-based inks in aqueous, solvent, and UV-curable formulations offer wide color gamuts with durability and display permanence well-matched to a range of requirements for applications in indoor and outdoor display. Ink Vehicles In general, up to 95% (by weight) of inkjet ink may be ink vehicle. There are three broad types of ink vehicles, each with different chemistries and characteristics: water-based ( aqueous ), solvent-based, and monomer-based ( UV-curable ). Within each type many different ink formulations have been developed for specific printer platforms, applications, and to give users options for economy versus performance. An ink vehicle is a mixture of several components. Together, these give the ink the physical and chemical properties required to perform functions critical to reliability and print quality such as: formation of ink droplets with repeatable volume, speed, and trajectory determining type and frequency of automatic printhead servicing maintaining consistent chemical and physical properties during ink storage and use keeping dyes in solution and pigments properly dispersed reducing microbial growth in the ink supply binding metal ions to prevent pigment precipitation keeping the drop generators and nozzle plate clean wetting the inside of the drop generators to keep them primed with ink retarding the evaporation of volatile ink components from printhead nozzles wetting the surface of the print medium to form printed dots immobilizing colorants at the surface of the print medium softening or dissolving the surface of nonabsorbent, uncoated materials (e.g., vinyl) forming a durable colorant layer that encapsulates pigments After the ink vehicle delivers colorant to the print medium, physical and chemical interactions occur on the surface to control drop spread ( dot gain ) and ink penetration. In some ink systems, different 9 Some HP inkjet ink cartridges may be used for a specific period after the Install Before date. See your printer s User s Guide for more details. 7

8 chemistries between ink colors (e.g., black and yellow inks) can immobilize pigments at the interface between wet dots to reduce color bleed. To produce a print that is ready for use, the liquid ink vehicle must be evaporated, absorbed, or solidified. For aqueous inks (except HP Latex Inks) and solvent inks, the bulk of the ink vehicle is evaporated outside the printer by natural or forced airflow, or it is captured in the coating of nanoporous print media. Nanoporous media produce prints that are dry to the touch out of the printer, but the ink vehicle is trapped in a porous matrix in the coating on a photobase paper. Some amount of the ink vehicle may evaporate slowly over time. HP Scitex aqueous and solvent-ink printers produce dry prints with in-line dryers using heat and forced airflow. HP Latex Inks are water-based inks that produce dry, ready-to-use prints using heating systems in the printer to evaporate the ink vehicle and to coalesce latex particles to form a durable colorant layer on the print. The ink vehicle in UV-curable inks is neither absorbed nor evaporated. All the ink remains on the print and the ink solidifies when exposed to intense ultraviolet (UV) light in the printer. Aqueous Inks Water is the primary ingredient of aqueous ink vehicles, representing up to about 70% by weight in some formulations. Water has a number of desirable physical and chemical properties that are wellsuited to the designs and materials used in HP Thermal Inkjet Technology. And, water is non-toxic and produces no volatile organic compounds (VOCs) when prints are produced, dried, and displayed. In general, the composition of aqueous inks is more complex than other types of inks. This is because water alone is not a practical ink vehicle for printing on the wide variety of media used in commercial and industrial applications. Aqueous inks typically contain water-soluble organic liquids called cosolvents, meaning that they work together with the solvent properties of water. Additives and cosolvents are needed to modify water s properties to obtain the required physical and chemical properties for an ink vehicle, and some of their functions are summarized in the table below. The ink components delivered by the ink vehicle, in addition to the colorant, typically include polymers or resins, which improve durability by encapsulating pigments and enhancing their adhesion to the surface of the print medium. In aqueous inks, these resins typically coat the pigment particles. HP Latex Inks use aqueous-dispersed polymer particles that encapsulate the pigments after curing in the printer. Surfactants and Co-solvents Humectant Preservative Chelating Agent Buffering Agent modify surface tension for drop ejection, keep nozzles primed with ink, wet the print media for dot formation and ink penetration, provide stable pigment dispersion controls ink evaporation from the printhead nozzles helps to prevent bacterial growth binds metal ions to prevent precipitation of pigments maintains ink ph HP Designjet printers with aqueous inks may be installed in office-like environments. They do not require special installation of ventilation equipment to meet occupational exposure limits for workplace health and safety regulations When multiple HP Designjet printers are used in high production environments, the release of water vapor as prints dry may require ventilation of the work area to control temperature and humidity. 8

9 With aqueous inks, handling new and used ink cartridges and waste ink involves a lower level of environmental, health, and safety precautions compared to solvent and UV-curable inks. Nevertheless, commercial and industrial inkjet inks should always be handled, used, stored, and disposed of in accordance with information provided in the ink s Material Safety Data Sheet (MSDS). 11 Certain used ink cartridges and printheads may be returned through the HP Planet Partners Program for free and convenient recycling. 12 Aqueous inks are extremely versatile. HP offers hundreds of different HP large-format printing materials developed and tested for use with HP aqueous inks. HP aqueous inks deliver the highest image quality and display permanence of all HP inkjet technologies when specific inks are used on specific HP largeformat printing materials. For example, HP 70 and HP 91 Vivera pigment inks on HP Premium Matte Photo Paper can deliver more than 200 years of fade resistance when displayed indoors away from direct sunlight. 13 HP offers four aqueous ink technologies for commercial and industrial printing: HP Vivera inks for HP Designjet T-series technical graphics printers HP Vivera pigment inks for HP Designjet Z-series graphic arts printers HP Latex Inks for the HP Designjet L25500 and L65500 Printers HP Scitex WB300 Supreme Inks for the HP Scitex FB6700 Flat Bed Printer HP Vivera Inks HP 72 Vivera inks C M Y pk mk G HP Designjet T600, T620, T770, T1100, T1200 HP ml Matte Black ink mk HP Designjet T1200 HP 72 Vivera inks are specifically formulated to deliver vivid and accurate colors, neutral grays, and crisp lines and text on over twenty Original HP media including bond and coated papers, clear and matte films, and high-gloss and semi-gloss photo papers. 14 HP 72 Vivera inks dry quickly to support high productivity from HP Designjet T1100 and T610 Printers, and these inks produce prints that are smudge resistant and ready to handle immediately after printing. HP 72 Vivera inks consist of a pigment-based matte black ink (mk) and five dye-based inks. These inks offer an excellent match to colors used in popular technical applications such as AutoCAD. HP Designjet T1100ps Printers using HP 72 Vivera inks produce a colorimetric match to 62% of PANTONE colors. 15 HP Vivera Pigment Inks HP 70 Vivera pigment inks C lc M lm Y lg pk mk HP Designjet Z2100 HP 70 Vivera pigment inks lc M lm Y lg pk mk G Gn B E HP Designjet Z3200 HP 73 Chromatic Red ink (a Vivera pigment ink) R HP Designjet Z3200 HP 91 Vivera pigment inks C lc M lm Y lg pk mk HP Designjet Z6100 HP 70 and HP 91 Vivera pigment inks were developed for HP Designjet Z-series printers for use in digital graphic arts and photographic reproduction on a wide range of coated and uncoated Original 11 MSDS for Original HP inks can be downloaded from 12 In the circa 45 countries and territories in which the HP Planet Partners program operates. Program features and availability varies. Where this program is not available, and for other consumables not included in the program, consult the Material Safety Data Sheet (MSDS) available at to determine appropriate disposal. 13 Display permanence rating for interior displays away from direct sunlight by HP Image Permanence Lab and Wilhelm Imaging Research, Inc., on a range of HP media. For details, see 14 See the Product Data Sheet for specific media designed and tested with HP Designjet T610 and T1100 printers and HP 72 Vivera inks. 15 Measured on HP Universal High Gloss Photo Paper. 9

10 HP large-format printing materials. HP 73 Chromatic Red ink is a new Vivera pigment ink that was introduced with the HP Designjet Z3200 Printers to increase the gamut in this important color. HP Vivera pigment inks use HP Electrosteric Encapsulation Technology (EET) to surround each pigment particle with an electrically-charged polymer ( resin ) coating. When the ink vehicle is absorbed by or evaporated from the print medium, this resin encapsulates the pigments and forms a durable colorant film on the surface. EET creates a stable dispersion of pigments in the ink to increase shelf and service life, improves ink jettability, and helps to prevent pigment coalescence on the print surface to improve image quality. HP 70, HP 73, and HP 91 Vivera pigment inks produce water-resistant prints that resist fading for more than 200 years on a range of HP media (interior display away from direct sunlight). HP 91 Vivera pigment inks produce interior in-window displays that resist fading for over 1 year unlaminated and over 3 years laminated. 16 HP Designjet Z2100 and Z6100 Printers feature 8-ink writing systems with five color inks and the HP Three-black ink set. HP Designjet Z3200 Printers use a 12-ink writing system with seven colors, the HP Quad-black ink set, and HP Gloss Enhancer. With HP 73 Chromatic Red ink, HP Designjet Z3200 Printers deliver a broad color gamut to produce exquisite color and black and white prints for photographic and digital fine art applications and provide coverage up to 95 percent of PANTONE colors for graphic arts. 17 HP Designjet Z3200 Printers deliver superb neutral tones with low metamerism and deep, rich blacks on matte, glossy, semi-gloss, and fine art papers. On glossy and semi-gloss photo media, HP Gloss Enhancer virtually eliminates bronzing and provides uniform print gloss across the full range of print densities and colors. HP Latex Inks HP 786 Latex Designjet Inks C lc M lm Y K HP Designjet L65500 HP 789 Latex Designjet Inks C lc M lm Y K HP Designjet L25500 HP Latex Inks, using HP s innovative aqueous-dispersed polymer ( Latex ) 18 technology, were introduced in 2008 as HP 786 supplies for the HP Designjet L65500 Printer and in 2009 as HP 789 supplies for the HP Designjet L25500 Printer. 19 HP Latex Inks provide print durability and display permanence comparable to eco-solvent inks 20 and low-solvent inks, 21,22 and their water-based formulation reduces the impact of printing on the 16 Water resistance and interior in-window display ratings by HP Image Permanence Lab on a range of HP media. Display permanence rating for interior displays away from direct sunlight by HP Image Permanence Lab and Wilhelm Imaging Research, Inc., on a range of HP media. For details, see % coverage of PANTONE MATCHING SYSTEM and PANTONE GOE systems, based on HP internal testing (PANTONE approval pending). See for final results. 18 Latex is a term that describes a stable, aqueous dispersion of microscopic polymer particles. It is important not to confuse the polymers used in HP Latex Inks with those found in natural materials, such as latex rubber. While some individuals experience skin irritation from contact with natural latex compounds, the synthetic polymers used in HP Latex Inks are non-allergenic. 19 The HP Designjet L65500 Printer produces prints up to 104-inches (2.64-m) wide. The HP Designjet L25500 Printer is available in 42-inch (1.07- m) and 60-inch (1.52-m) models. 20 For the HP Designjet L25500 Printer, HP image permanence and scratch, smudge, and water resistance estimates by HP Image Permanence Lab. Outdoor display permanence tested according to SAE J2527 using HP Latex and eco-solvent ink on a range of media, including HP media; in a vertical display orientation in simulated nominal outdoor display conditions for select high and low climates, including exposure to direct sunlight and water; performance may vary as environmental conditions change. Scratch, smudge, and water resistance tested using HP Latex and ecosolvent inks on a wide range of media, including HP media; water resistance is comparable when printed on water-resistant substrates. Laminated display permanence using GBC clear gloss 1.7 mil hot laminate. Results may vary based on specific media performance and scratch testing methodology. For more information, see 21 Low-solvent inks are the HP 781 and HP 791 inks used in HP Designjet 8000sr, 9000s, and 10000s Printers. 22 For the HP Designjet L65500 Printer, HP image permanence and scratch, smudge, and water resistance estimates by HP Image Permanence Lab. Display permanence tested according to SAE J2527 using HP Latex and low-solvent inks on a range of media, including HP media; in a vertical display orientation in simulated nominal outdoor display conditions for select high and low climates, including exposure to direct sunlight and water; performance may vary as environmental conditions change. Scratch, smudge, and water resistance tested using HP Latex and low-solvent inks on a wide range of HP media; water resistance is comparable when printed on water-resistant substrates. Laminated display permanence using Neschen 10

11 environment. From durable outdoor signage to odorless indoor displays, 23 HP Latex Inks provide highproductivity printing and broad media versatility across both coated and uncoated substrates. And, the HP large-format printing materials portfolio 24 developed and tested with HP Latex Inks includes seven (7) recyclable substrates and five (5) that are covered by the HP Large-format Media take-back program. 25 Dry, ready-to-use prints made on vinyl with the HP Designjet L25500 and L65500 Printers and HP Latex Inks can be laminated immediately using cold, hot, and liquid lamination methods. 26 HP Latex Inks produce a flexible colorant layer for use in applications where it s important that the print can be bent, stretched, and folded without cracking. HP Latex Inks are water-based and offer important advantages over eco-solvent and low-solvent inks used in commercial and industrial inkjet printing. No special workplace ventilation is required 27 to use the HP Designjet L25500 and L65500 Printers. HP Latex Inks enable an improved printing environment because they do not require special handling, contain no materials requiring hazard warning labels, and are non-flammable and non-combustible. 28 In the European Union (EU) widely recognized as having the most comprehensive set of labeling guidelines in the world HP Latex Inks do not require hazard warning labels in accordance with EU Directive 1999/45/EC. HP Latex Inks do not produce ozone emissions during printing and contain no HAPs (hazardous air pollutants) 29 or sensitizers and comply with Nordic Swan criteria, version 4.2. HP Latex Inks in the HP Designjet L25500 and L65500 Printers produce durable, high-quality output on a range of media, and achieve outdoor display permanence up to 3 years unlaminated and up to 5 years laminated. 20,22 For prints produced on the HP Designjet L25500, HP Latex Inks offer display permanence and scratch, smudge, and water resistance (on water-resistant media) comparable to eco-solvent inks. 20 For prints produced on the HP Designjet L65500, HP Latex Inks offer display permanence and scratch, smudge, and water resistance (on water-resistant media) comparable to low-solvent inks. 22 Prints for indoor, in-window display on a range of media last up to 5 years unlaminated and up to 10 years with lamination liter HP 786 Latex Designjet Ink Cartridges can further reduce the impact of printing on the environment with a design that includes a recyclable outer container made of cardboard. Its construction reduces material use and includes a recyclable cardboard container accounting for approximately 70% of the weight of the used ink cartridge. 31 And, as ink is withdrawn, an internal ink bag collapses in a way that maximizes the amount of usable ink. Solvoprint Performance Clear 80 laminate. Results may vary based on specific media performance. For more information, see 23 Printers using HP Latex Inks use internal heaters to dry and cure the latex polymer film. Some substrates may have inherent odor. 24 Visit for a description of HP large-format printing materials including availability in roll widths and lengths. 25 HP offers the HP Large-format Media take-back program in the U.S. and Europe, through which most HP recyclable signage media can be returned, availability varies. Some recyclable papers can be recycled through commonly available recycling programs. For details visit Aside from this program, recycling opportunities for these products are currently only available in limited areas. Customers should consult local recycling resources for recycling these products. 26 Lamination compatibility is highly dependent on the printing material. HP recommends testing lamination performance prior to any important job. 27 Special ventilation is not required to meet US OSHA requirements on occupational exposure to VOCs from HP Latex Inks. Special ventilation equipment installation is at the discretion of the customer no specific HP recommendation is intended. Customers should consult state and local requirements and regulations. 28 HP water-based Latex Inks are not classified as flammable or combustible liquids under the USDOT or international transportation regulations. These materials have been tested per the Pensky-Martins Closed Cup Method and the flash point is greater than 110 deg C. 29 No ozone products expected based on ink composition and printing technology. The inks were tested for Hazardous Air Pollutants per U.S. Environmental Protection Agency Method 311 (testing conducted in 2008) and none were detected. HAPs are air pollutants which are not covered by ambient air quality standards but which, as defined in the Clean Air Act, may present a threat of adverse human health effects or adverse environmental effects Interior in-window display ratings by HP Image Permanence Lab on a range of media including HP media. HP in-window predictions are based on test data under Xenon-Arc illuminant. Calculation assumes 6,000 Lux/12 hr day. Laminated display permanence using Neschen Solvoprint Performance Clear 80 laminate. For more information, see 31 Consult with your local authority to determine the appropriate method of waste disposal for the ink bag. 11

12 Curing HP Latex Inks Unlike other aqueous inks used in HP Designjet printers, HP Latex Inks cannot dry in air. They must be cured in the printer with heat and forced airflow. The writing systems in the HP Designjet L25500 and L65500 Printer include independent Print Zone and Curing Zone 32 heating systems to cure HP Latex Inks. While dots are being printed in the Print Zone, radiant heat and forced air evaporate water from the ink. This process causes an increase in viscosity that controls dot gain and color-to-color interactions, and it concentrates the co-solvents so that they can effectively soften the surface of uncoated vinyl to bond with latex polymers in the colorant layer. The key to understanding how water-based HP Latex Inks can soften vinyl is to recognize that after water in the ink vehicle is evaporated in the Print Zone, the co-solvents in HP Latex Inks work at full concentration (i.e., undiluted by water) and at elevated temperatures in the Curing Zone. The curing process for HP Latex Inks adds to the functionality of the co-solvents, which are similar in type and concentration to co-solvents in HP Vivera pigment inks used by HP Designjet printers in office-like environments. As the printed substrate passes through the Curing Zone heater, the co-solvents evaporate and latex particles coalesce to form a continuous polymer layer that bonds to the substrate and encapsulates the pigment to form a durable colorant film. The print is completely dry and ready to use, finish, and prepare for shipment. HP Scitex WB300 Supreme Inks HP Scitex WB300 Supreme C lc M lm Y K HP Scitex FB6700 HP Scitex PT10 pretreatment HP Scitex FB6700 HP Scitex PT20 pretreatment HP Scitex FB6700 HP Scitex WB300 Supreme inks are water-based, industrial inkjet inks developed for use in the HP Scitex FB6700 Printer. These inks are used on large-format media such as corrugated and compressed cardboard, polypropylene, styrene, acrylic, polycarbonate, foam board, foam PVC, and other rigid or flat substrates. Because some of these substrates may be folded or vacuum-formed when used in shortrun packaging, POP displays, and exhibition stands, HP Scitex WB300 Supreme inks produce a flexible, durable colorant layer that does not crack. The water-based formulation of HP Scitex WB300 Supreme inks facilitates an improved industrial printing environment. These inks are odorless, non-flammable, non-combustible, non-toxic, and nonreactive. They do not produce ozone emissions, no special ventilation is required to meet occupational exposure limits, and there are no requirements for air discharge permitting. HP Scitex FB6700 Printers can apply a liquid pretreatment (HP Scitex PT10 or PT20) to the substrate before imaging. This improves colorant adhesion, particularly on non-absorbent materials such as polypropylene, styrene, and others. Polymers in HP Scitex WB300 Supreme inks are cured by an in-line hot air dryer (external to the printer module) to produce prints that are UV-, water-, and abrasion-resistant according to ASTM D These prints offer a very wide gamut with offset-like vibrancy. HP Latex Inks and HP Scitex WB300 Supreme inks both use aqueous-dispersed polymers to produce durable prints, but they are very different formulations with different chemical and physical properties. HP Latex Inks were developed for use with HP Thermal Inkjet printheads. HP Scitex WB300 Supreme inks were developed for use in Aprion piezoelectric printheads. Compared to HP Scitex WB300 Supreme inks, HP Latex Inks do not use a pretreatment of the print medium and have a higher loading of polymers in the ink vehicle that requires curing inside the printer with a two-zone heating system. 32 Printheads scan in the Print Zone to apply ink to the print medium. The print medium is then moved (advanced) into the Curing Zone. 12

13 Solvent-based Inks HP Designjet 781 low-solvent C lc M lm Y K HP Designjet 8000sr HP Designjet 791 low-solvent C lc M lm Y K HP Designjet 9000s, 10000s HP Scitex TJ100 Supreme C lc M lm Y K HP Scitex TJ8350 HP Scitex TJ100 Flash C lc M lm Y K HP Scitex TJ8350 HP Scitex XL300 Supreme C lc M lm Y ly K lk HP Scitex XL1200, XL1500 HP Scitex XL400 Supreme C lc M lm Y ly K lk HP Scitex XL1200, XL1500 The function of an organic solvent in the ink vehicle is to dissolve or soften the surface of a nonabsorbent material, such as vinyl, and to evaporate quickly to produce dry prints at high production speeds. Solvent inks produce durable prints on low-cost, uncoated materials for applications where the image is exposed to sunlight, moisture, and may require periodic cleaning. These inks are well-suited for outdoor applications such as signage, event banners, vehicle and building wraps. Because media with special ink-receptive coatings are not required, the cost per square meter for print production using solvent inks is among the lowest available. The formulation of solvent inks is somewhat simpler than aqueous inks. The solvent itself provides many of the functions of co-solvents and additives. Solvents Polymer/Binder Dispersing Agent Colorant modify surface tension for drop ejection, keep nozzles primed with ink, wet the print media for dot formation and ink penetration, provide stable pigment dispersion, soften or dissolve the substrate for colorant adhesion and durability forms a durable film on the print medium that encapsulates pigments provides stable pigment dispersion pigments (dyes may be added to increase chroma) Solvent inks actually dissolve a thin layer of the print medium. Pigments are absorbed into and are encapsulated by this layer. This process integrates the colorant into the print medium to produce a print with high scratch-, smudge-, and water-resistance. HP low-solvent inks 33 soften the surface of uncoated vinyl so that binders in the ink form a durable bond between the substrate and a layer of pigments encapsulated by the binder. Solvent inks produce prints that have high resistance to smearing when wiped with alcohol-containing cleaners. The colorant layer is flexible allowing prints to be bent, folded, or stretched without cracking. This property makes solvent-ink prints on adhesive-backed vinyl ideal for vehicle wraps, where the image must be stretched to conform to the vehicle body and must be cleaned periodically. Inkjet printers using solvent inks produce volatile organic compounds ( VOCs ) as the ink evaporates during printing and while prints are dried, handled, and stored. Limits on worker exposure to VOCs and the handling, use, storage, and disposal of organic solvents are subject to local, state, and federal environmental, health, and safety regulations. 34 The concentration of specific compounds determines the level of discomfort and safe exposure to VOCs. In excessive concentration, VOCs can cause headache, dizziness, and nausea along with irritation of the eyes, nose, throat, and skin. Some solvent ink printers use in-line high-speed dryers or off-line print storage to evaporate solvents from the print to dry it before handling, shipping, and display. This helps to reduce the release of 33 HP low-solvent inks are defined according to what is currently known in the industry as low-solvent inks. 34 MSDSs for Original HP inks can be downloaded from 13

14 objectionable solvent odors at the point of display. But, completely drying solvent-ink prints in the print shop releases additional VOCs into the work area, and this process may require special ventilation to meet occupational exposure requirements. Proper installation, operator training, and observance of environmental, health, and safety regulations is important to enable the safe operation of solvent-ink printers. HP uses low-solvent inks in commercial printing solutions based on the HP Designjet 8000sr-, 9000s, and 10000s Printers. These inks, offered in 6-colors in HP 781 and HP 791 supplies, are formulated with solvents that have less demanding environmental, health and safety requirements for use and handling compared to solvents used in inkjet inks for industrial printing. An HP Designjet Air Purifier System is available for the HP Designjet 8000sr, 9000s, and 10000s Printers. Specially designed for HP low-solvent inks, the HP Designjet Air Purifier System provides highly-effective air filtration for the working area environment by capturing VOCs released inside the printer during operation. HP 781 and HP 791 inks produce prints with excellent durability without lamination on uncoated, lowcost substrates such as vinyl, fabric, films, banner scrim, and paper. Images resist fading for up to 3 years without lamination and are scratch, smear, and crack resistant. 35 HP 781 and HP 791 inks deliver vivid color prints with a wide color gamut offering saturated magentas, reds, cyans, and blacks. Outdoor durability of HP Scitex solvent inks is tested according to standard ASTM D HP Scitex TJ100 inks are offered in two formulations and in 6-colors for the HP Scitex TJ8350. HP TJ100 Supreme inks provide up to 2 years outdoor durability 36 ; economical HP Scitex TJ100 Flash inks are designed for applications requiring lower durability. HP Scitex XL300 Supreme and XL400 Supreme inks are used in 8-color writing systems in the HP Scitex XL1200 and XL1500 Printers. These printers support 4-, 6-, and 8-color print modes. Both HP Scitex XL300 Supreme and XL400 Supreme inks offer up to 2 years outdoor durability. 36 Compared to XL300 inks, the XL400 formulation provides higher output quality with reduced banding and better solid area fills and higher productivity based on reduced in-line maintenance of printheads. UV-curable Inks HP 788 HP 788 Specialty C lc M lm Y K C lc M lm Y K HP Designjet H35100/35500, H45100/ HP Designjet H35100/35500, H45100/45500 HP FB200 Specialty Flexible C lc M lm Y ly K lk + W HP Scitex FB6100/6050 HP FB210 C lc M lm Y ly K lk + W HP Scitex FB6100/6050 HP FB220 Scitex C lc M lm Y K HP Scitex FB7500 HP FB221 Scitex C lc M lm Y K HP Scitex FB7500 HP Scitex FB250 C lc M lm Y K HP Scitex FB950 HP Scitex UV850 C lc M lm Y K HP Scitex TJ8550 HP XP220 C lc M lm Y ly K lk C M Y K HP Scitex XP2100, XP2750, XP5100 HP Scitex XP5300 HP XP230 Specialty Billboard C M Y K HP Scitex XP2300, XP5300 HP XP231 Specialty Billboard C M Y K HP Scitex XP2300, XP Image permanence and application durability under typical exposure in vertical display conditions and varies as environmental conditions change. 36 Durability depends on media. 37 HP Designjet H35100 and H45100 Printers use a 4-color C M Y K system; HP Designjet H35500 and H45500 Printers use a 6-color system. 14

15 UV-curable inks do not dry by evaporation: inks solidify on the print medium upon exposure to intense ultraviolet light. The colorant film adheres to the surface by penetrating and solidifying ( keying ) into small surface pores and by chemical bonding to some materials. Formulating UV-curable inks for different applications (and substrate chemistries) allows UV-curable inks to be a nearly universal ink technology that can print on rigid and flexible substrates and on absorbent (e.g., papers, textiles) and nonabsorbent materials (e.g., plastics, metals, glass). UV-curable inks are typically formulated with the following components: Monomers Photoinitiators Oligomers Surfactants Oxygen Inhibitors Dispersing Agent Colorant provide a low viscosity liquid carrier, crosslink (polymerize) to form a solid film encapsulating colorant, provide stable pigment dispersion initiate and sustain UV-curing process when ink is exposed to UV light provide film durability and flexibility improve wetting of the print medium inhibit polymerization under storage conditions provide a stable pigment dispersion pigment UV-curable ink vehicles contain liquid monomers, oligomers, 38 and components sensitive to ultraviolet light called photoinitiators. Monomers in HP UV-curable inks are individual molecules with acrylate functionality. Oligomers are short polymer chains that control properties of the cured ink film, such as flexibility and elongation. This allows prints made with UV-curable inks to resist cracking when the printing material is bent, folded, or stretched. When printed dots of UV-curable ink are exposed to UV light, photoinitiators produce molecules called free radicals. 39 Free radicals cause liquid monomers to link together to form chains, called polymers, and polymers to crosslink to form a durable, solid coating of colorant on the substrate. In free radical chemistry, the ink must be exposed to UV light until essentially all the monomer is polymerized. Complete polymerization of the ink requires UV light to penetrate the entire ink layer down to its interface with the print medium. Pigments in the ink absorb some UV wavelengths and allow some transmission of others. Which UV wavelength(s) can fully penetrate the ink layer depends on the ink color (i.e., the pigment). For this reason, two or three photoinitiators, each sensitive to a different UV-wavelength, are generally used together to ensure a complete cure all the way through the ink layer. UV-curable inks produce very low levels of VOCs, and in this respect have a significantly lower environmental impact than solvent inks. Ozone is created when UV light interacts with oxygen in the air, and UV-curable printers use fans and filters to capture ozone and minimize its release into the work space. Contact with monomers or exposure to monomer aerosol created during printing may cause skin, respiratory, and eye irritation. Consult the ink MSDS for detailed information about occupational exposure and handling for the HP UV-curable inks used in your printer. 40 UV-curable inks offer a number of benefits to industrial print production. Once on the print medium and exposed to UV light, UV-curable inks undergo a rapid increase in viscosity from a liquid to a durable solid in about 100 milliseconds. This minimizes dot spread, feathering, and ink penetration into absorbent media or coatings. This rapid-curing characteristic allows UV-curable inks to print with high quality at high productivity on almost any substrate with precise dot control for sharp lines and edges, 38 A monomer is the basic molecular element that forms a chain or matrix with other monomers in a process called polymerization. An oligomer is a short chain of monomers; a long chain or matrix of monomers is a polymer. 39 UV-curable inks may also use cationic chemistry for polymerization of the monomer. All HP UV-curable inks employ free radical chemistry. 40 MSDSs for Original HP inks can be downloaded from 15

16 and repeatable dot properties for color accuracy. High color saturation is achieved because UVcurable inks form a film of colorant that stays at the surface of print media. With HP UV-curable inks, the ink printed onto the print medium converts into a solid without any material loss to evaporation. Prints come out of UV-curable printers ready for use. Because an in-line print dryer is not needed, printers can use less production floor space than a similar printer using aqueous or solvent inks. 41 HP Scitex FB200 Specialty inks and FB210 inks are used in 4-, 6-, or 8-color modes in the HP Scitex FB6100/6050 Printers. These inks provide up to 2 years of UV and water resistance. 42 A White Ink Kit is available for printing White UV-curable ink when Scitex FB6100/6050 Printers are operated in 6- colors plus White mode. HP FB220 and FB221 Scitex Inks are used in the HP Scitex FB7500 Printers. HP FB221 Scitex inks are designed for use on flexible (mainly self-adhesive) substrates. HP Scitex UV850 inks used in the HP Scitex TJ8550 Printer provide up to 2 years UV and water resistance. 43 Up to 2 years of UV and water resistance 42 is provided by HP XP220 Scitex Inks in HP Scitex XP2100, XP2750, and XP5100 Printers and by HP XP230 and XP231 Scitex Inks in HP Scitex XP5300 Printers. At the present time, outdoor UV and water resistance specifications are not available for HP 788, HP Scitex FB250 inks, and HP FB220 and HP FB221 Scitex inks. Finished graphics printed on 3M graphic media with HP 788 Specialty inks are backed by the 3M MCS Warranty and may be warranted for up to five years of outdoor use. 44 HP Large-format Printing Materials HP large-format printing materials have been developed with Original HP inks to support a wide range of HP printing solutions. These materials include coated and uncoated papers, films, vinyl, textiles, Tyvek, and others. With hundreds of HP-branded media to choose from, HP provides customers with selection tools and application information at Original HP inks and HP large-format printing materials are developed and tested together, so it is useful to understand some fundamentals of ink-material interactions. Printing materials may have a chemical surface treatment or a coating over an absorbent or nonabsorbent core. A surface treatment modifies the chemical (and optical) properties of the surface of the printing material. A coating also modifies the surface properties and includes an ink-receptive layer. Surface Treatments A surface treatment helps the ink wet the substrate, controls dot spread and color bleed, and may improve the bonding of the colorant layer to the substrate. Surface treatments can also control penetration of the colorant into absorbent media, add optical brighteners and whiteners, and minimize cockle. 45 HP Surface Treatment Technology High Density Polyethylene (HDPE) fibers are used in the production of HP DuPont Tyvek Banner and HP HDPE Reinforced Banner printing materials. HDPE has many desirable physical properties: it has 41 For example, with equivalent sq/m per hour productivity, the solvent-based HP Scitex TJ8350 has a site requirement of 3.25 X 7.5 X 18m whereas the HP Scitex TJ8550 with UV-curable inks needs 3.25 X 9 X 10m. The primary difference is that UV-curable inks eliminate the in-line dryer. 42 UV and water resistance without coating or lamination; conditions apply. 43 According to standard ASTM D Durability depends on media. 44 Contact 3M for more information on the MCS Warranty. 45 Cockle occurs as cellulose-based materials swell upon exposure to water in the ink vehicle. Cockle can produce displacements out of the plane of the sheet to give it a wrinkled appearance. Paper may have wet cockle, which occurs as ink is applied, and dry cockle, where the sheet is permanently deformed and wrinkled. In some cases, a sheet will dry without cockle even though wet cockle has occurred. Some aqueous inks contain additives that minimize cockle. The design of the printer platen in the print zone can reduce cockle with vacuum hold-down and channels that allow paper to deform in a controlled manner as it expands during printing. 16

17 high tensile strength and is lightweight, it is durable outdoors, and it is recyclable 46. HDPE is also resistant to many solvents, and this feature gives HDPE widespread use in packaging for food and chemicals. But, it is this solvent-resistance that poses an issue for image quality and print durability: when printing HDPE materials with aqueous and low-solvent inks, the ink vehicle cannot soften or dissolve the surface. Therefore, no interface layer forms between the substrate and the colorant layer to give good adhesion and print durability. Tyvek is formed from HDPE fibers fused together under heat and pressure. The surface of a Tyvek sheet is a matrix of randomly-oriented fibers with large, open pores. Pigments can be carried deep into the fiber matrix when ink penetrates the surface of untreated Tyvek. When this happens, a print may have high color bleed and feathering, low edge sharpness, low color saturation, reduced color gamut, and low optical density. To improve imaging performance and print durability of HP Latex Inks and HP low-solvent inks on HP DuPont Tyvek Banner and HP HDPE Reinforced Banner materials, HP developed a proprietary surface treatment employing a blend of polymers designed to work with these inks. This treatment is applied during manufacture of the banner material and is called HP Surface Treatment Technology. The HP Latex Inks and HP low-solvent inks wet and dissolve these polymers to control ink spread and penetration. After the ink vehicle evaporates, the colorant layer forms a durable bond to the treated HDPE surface. HP Surface Treatment Technology on HDPE-based substrates improves image durability, color saturation and color gamut, and edge sharpness. Coated Media Coated media have an ink-receptive layer applied over an absorbent or nonabsorbent core. The imaging characteristics of coated print media are determined by the physical and chemical characteristics of the coating; the mechanical properties of the print (e.g., thickness, weight, and stiffness) are determined by the core. In general, the highest levels of image quality are obtained by using coated media recommended for the inks in the printer. 47 Original HP inks and coatings on HP large-format printing materials are developed together, and both are manufactured with high standards of quality control to give consistent, high-quality results. The coating absorbs inks in a controlled manner to give predictable drop spread ( dot gain ) and colorant penetration. This produces dots with consistent size, controls color-to-color bleed, and reduces print dry-time. 48 Coatings can provide the uniform, bright, white background essential to accurate color reproduction, and a surface finish (e.g., glossy, semi-gloss, and matte) appropriate to the application. These features are especially important in photographic, fine art, technical and presentation graphics, and graphics arts applications. The physical and chemical interactions between ink and the coating are so important that the display permanence and water-resistance of prints, especially those made with dye-based aqueous inks, is given for specific inks on specific printing materials. 49 Setting ink limits and linearizing the printer for the inks and printing material can give the widest color gamut, the greatest dynamic range for each ink color, and consistent color in print production. Generating an ICC Profile for the ink, print mode, and printing material is important for color accuracy. 50 There are three main types of coatings: porous coatings, nanoporous coatings, and swellable coatings. 46 HP offers the HP Large-format Media take-back program in the U.S. and Europe, through which most HP recyclable signage media can be returned, availability varies. Some recyclable papers can be recycled through commonly available recycling programs. For details visit Aside from this program, recycling opportunities for these products are currently only available in limited areas. Customers should consult local recycling resources for recycling these products. 47 See information on supplies recommended for a specific HP printer at 48 Primarily, this is the time required before the print can be handled without smearing the ink. It may take hours or days for the bulk of the ink vehicle to evaporate depending on conditions of temperature and humidity. 49 Display conditions also apply. See 50 HP Designjet Z-series printers have a built-in spectrophotometer that can automatically generate an ICC profile. HP s Closed-Loop Color Calibration delivers consistent results for a combination of inks and printing material. 17

18 Porous Coatings Porous coatings are opaque and usually made with an ink-receptive layer containing clay, calcium carbonate, or silica. For example, porous coatings are used in HP technical graphics papers and HP Heavyweight Coated Paper. These coatings quickly absorb the ink vehicle to produce fast-drying 51 prints with sharp lines and crisp text. Porous coatings are designed to hold the colorant (both dyes and pigments) at or close to the surface of the print for high black optical density and excellent color saturation. They can provide the smooth, bright, white surface that is ideal for technical and presentation graphics. Nanoporous Coatings HP Instant-dry media 52 use nanoporous coatings to produce prints that are dry to the touch out of the printer. These media offer good water-resistance, especially for dye-based inks. 53 A nanoporous coating is composed of several layers over a photobase paper. Photobase paper forms the core of the print and provides a bright, white background for color imaging. This paper gives the print its thickness, weight, and stiffness. An outer, ink-permeable protection layer provides scratch and fingerprint resistance and can produce photographic prints with very high gloss. Ink vehicle and dyes pass through the protection layer to be absorbed by the imaging layer, where ink fills the voids in an open-matrix of pores between microscopic polymer particles. If the void capacity of the imaging layer is exceeded by printing with too much ink, 54 liquid ink could be left on the surface ruining the print and possibly requiring printer maintenance. A resin coating provides a smooth substrate for the imaging and protection layers. It reduces curl after printing by blocking ink (and water) from entering the photobase paper. Dyes are trapped in the pores of the imaging layer. This gives dye-based inks on nanoporous media good water-resistance. But because the surface is permeable, atmospheric gases can diffuse into the imaging layer to react with dyes. Dye-based inks on nanoporous media generally have lower display permanence compared to the same inks on swellable media. 53 Print permanence and durability can be improved by lamination. Prints on nanoporous media can be laminated and used immediately because the ink vehicle does not leave the substrate. Pigment particles remain on the surface of nanoporous media because they are too large to penetrate through the protection layer. This can cause variations in image gloss between areas of different print density and color, particularly between image highlights and the midtones and shadows. Image highlights are unprinted areas (or areas with low ink density). These areas are dominated by the surface finish and color of the substrate. Midtones and shadows have higher ink density, and the filmforming characteristics of pigment inks can affect gloss in these regions. Gloss uniformity can be improved by printing pigment inks on HP photo papers with a semi-gloss, satin, or matte finish. HP s Gloss Enhancer used in the HP Designjet Z3200 Printers improves gloss uniformity by printing a colorless ink where needed to match gloss across the full range of colors and optical densities. 51 The prints are smudge-resistant and ready for use within shortly after printing. Complete evaporation of volatile components of the ink vehicle may take several hours or longer, depending on ambient temperature and humidity. 52 For example, HP Premium Instant-dry Gloss Photo Papers for HP Designjet Z3200 Printers. 53 See 54 This could occur if the wrong paper, for example one requiring a higher ink load, were selected in the printer driver. 18

19 Swellable Coatings Swellable coatings protect the dyes from atmospheric gases and offer the longest display permanence for dye-based prints. However, swellable coatings for aqueous inks are softened by water and generally offer poor water-resistance and wet-smudge resistance. 53 Prints should be protected by displaying them behind glass or by lamination after the print is dry. Swellable coatings consist of several layers over a photobase paper. The imaging layer and undercoat are made from natural and synthetic polymers. The imaging layer swells as it absorbs ink vehicle and dyes. When the ink vehicle evaporates from both layers, the coating shrinks to its original thickness and the imaging layer encapsulates the dyes. Prints dry by evaporation of volatile components in the ink vehicle. While prints may be dry to the touch and handled minutes after printing, drying may take hours or days depending on temperature and humidity. 55 A resin coating provides a smooth substrate for the imaging and protection layers. It prevents curl after printing by blocking ink (and water) from entering the photobase paper. Pigments are too large to penetrate swellable coatings, and they remain on the surface as ink vehicle is absorbed by the imaging layer and undercoat. This can lead to gloss variations and bronzing as discussed for pigment inks on nanoporous media. Absorbent Media Absorbent media allow aqueous and solvent ink vehicles to penetrate into the substrate as the print is produced. Plain paper is an example of an absorbent media. The ink vehicle may penetrate completely through the sheet under some circumstances. Strikethrough occurs when the ink vehicle carries dyes far enough through the sheet that a reversed image appears on the back side. Prints on absorbent media can be handled once the ink vehicle is completely absorbed and the colorant binds to the surface. Prints may feel slightly damp until volatile components in the ink vehicle evaporate. This process occurs naturally or may be accelerated by a heater and forced airflow. If UV-curable inks penetrate too deeply into absorbent media, UV light may not reach all the ink. In this case, they will not be completely cured. At the surface, UV-curable ink fills and solidifies within open pores to produce a mechanical bond to the printing material. This process is called keying. The essential difference between absorbent and other types of printing materials is that the ink vehicle penetrates into and is absorbed by the core material of the sheet. Papers may be multi-layer structures with high-quality fibers in an outer layer covering a core of coarser fibers designed to provide thickness, stiffness, and strength. The schematic drawing at left shows how aqueous and solvent ink vehicles penetrate the porous structure of absorbent media. 56 In general, dyes penetrate farther than pigments, which stay at or near the surface. 55 Consult usage information supplied with the printing material. For example, dry time for HP Premium Plus Satin Photo and Photo Gloss Papers is specified as 5 minutes at 23ºC and 50% RH. HP recommends allowing prints on Premium Plus Photo Papers to air dry for one day at less than 70% RH before mounting behind glass or plastic. 56 UV-curable inks also penetrate to form a mechanical bond to the surface, but this penetration is limited by the higher viscosity of these inks and their rapid solidification. 19

20 The surface of an uncoated paper printed with dyes and pigments is seen in the figure at left in two microscopic views. 57 In the image labeled dye, dye molecules (too small to be seen) have coated the surface fibers and been carried into the fiber matrix by the ink vehicle. 58 In the image labeled pigment, a polymer film containing pigment particles has coated the surface fibers. Dyes are chemical molecules that are small enough to be carried by the ink vehicle deep into absorbent media, and this can reduce black optical density and color saturation. Printing with higher ink limits in an attempt to leave more dye at the surface can cause color bleed and feathering, where ink wicks along surface fibers and reduces edge sharpness, and strikethrough. Dye molecules can be damaged by exposure to atmospheric pollutants (e.g., ozone) and UV light, and dyes may redissolve when the print is exposed to water. For these reasons, dye-based prints on absorbent media generally have lower display permanence and water resistance compared to prints on coated media. Print permanence and durability can be improved by laminating prints with a thin plastic film that blocks UV and protects the print from gases, water, and abrasion. Lamination improves the durability of prints made with pigment inks on absorbent media by providing a mechanical barrier against water and abrasion. Lamination is especially useful for making prints more durable on paper-based and other media that may not be very water- or abrasion-resistant. Pigments are too large to penetrate deeply into most absorbent or porous media. Pigment penetration can be reduced by causing pigments to separate from the ink vehicle at or near the surface of the printing material. For this purpose, the ink vehicle can contain binding agents or polymers 59 or pigment particles can be coated by resins. 60 In addition, chemical treatment of the surface and changes in ink composition as some ink vehicle components penetrate more rapidly than others can cause the pigments to crash, meaning that they are no longer dispersed by the ink vehicle and carried with it. Once separated from the vehicle, pigments remain at or near the surface of the print medium as the ink vehicle is absorbed into the substrate. Nonabsorbent Media Nonabsorbent media do not allow the ink vehicle to penetrate into the bulk of the printing material. Plastic materials, such as backlit films and vinyl, are examples of nonabsorbent media. Although inks designed for nonabsorbent, uncoated media (such as vinyl) contain solvents that soften or dissolve the surface, the ink penetrates only a few microns and the print dries by natural or forced evaporation. This figure shows a schematic cross-section of vinyl printed with a solvent ink. The solvent dissolves a thin surface layer, pigments diffuse into this layer, and the solvent evaporates leaving the pigments encapsulated by the substrate material. HP s low-solvent inks soften the surface to improve adhesion to a binder in the ink vehicle that forms a polymer film encapsulating the pigments. HP Latex Inks use co-solvents to soften vinyl for adhesion to the filmforming latex polymers that encapsulate the pigments. A surface treatment can be used to improve adhesion of inks that do not dissolve or soften the surface of nonabsorbent materials. For example, the HP Scitex FB6700 Printer applies a liquid pretreatment to the substrate before printing with (water-based) HP Scitex WB300 Supreme inks. 57 Electron microscope images, source: HP R&D. The white bar represents 10 microns. 58 The small, white globules around the fibers are sizing agents and other additives. 59 For example, the latex particles in HP Latex Inks. 60 For example, Vivera pigment inks with Electrostatic Encapsulation technology. 20

21 UV-curable inks can be formulated to make a durable chemical bond to many nonabsorbent media such as glass, engineering plastics, metal, vinyl, polypropylene, and others. UV-curable inks can also fill small surface pores to form a mechanical bond upon solidification. Inkjet Printhead Technologies The choice of inkjet printhead technology depends on many factors including ink formulation, system design, and performance objectives. HP Thermal Inkjet and piezo inkjet printheads are used in HP s commercial and industrial inkjet printing solutions. How HP employs different inkjet technologies across printer platforms is summarized below: Aqueous Inks HP Thermal Inkjet printheads in HP Designjet T-series, Z-series, and L-series printers Aprion piezo printheads in the HP Scitex FB6700 Printer Solvent Inks OEM piezo printheads in HP Designjet 8000sr, 9000s, and 10000s Printers OEM piezo printheads in HP Scitex printers UV-curable Inks OEM piezo printheads in HP Designjet H-series and HP Scitex printers HP Scitex X2 piezo printheads in the HP Scitex FB7500 Printer. HP Thermal Inkjet Printheads with Scalable Printing Technology HP Scalable Printing Technology ( SPT ) is the result of HP s investment of $1.4 billion and four years of research and development. SPT printheads incorporate fluidic design and electronic control features that are needed to meet the demands of commercial and industrial inkjet printing. Since the introduction of HP s first SPT-based inkjet products in 2005, SPT designs and processes have allowed HP to leverage R&D, ink and printhead design, and HP s manufacturing economies of scale across all of HP s printing markets. Using proven technologies, SPT-based printheads allow HP Designjet Z-series, T-series, and L-series printers to deliver higher quality at higher speeds with more ink colors and with advanced ink formulations, such as HP Latex Inks. A cross-sectional detail of a single SPT drop generator is shown in the figure at left. To get a sense of scale in this drawing, the height of the drop generator and nozzle plate structure (shown in a tan color) is less than the thickness of a human hair. Many HP Thermal Inkjet printheads, also called die, 61 are produced together on a silicon wafer using SPT integrated circuit manufacturing processes customized for HP inkjet applications. SPT offers higher density circuitry that can place more electronic functionality on the printhead than was possible in previous generations of HP Thermal Inkjet printheads. Each SPT-based die incorporates electronic circuits that process input and output signals, manage power, control the drop generators, and measure printhead temperature. Ink channels, drop generator chambers, and nozzles for the printheads are built together across the surface of the silicon wafer by applying thin layers of photo-sensitive epoxy (seen as the tan-colored materials in the figure). The top-most layer is exposed to light through an optical mask. This polymerizes the material that will remain in-place, and undeveloped material is chemically removed. 61 This term comes from integrated circuit (IC) manufacturing. 21

22 Repeating this process and then slicing the wafer into die produces complete, integrated printhead structures with features that are defined and aligned together with sub-micron precision. With thousands of identical drop generators on each printhead, 62 SPT processes deliver high print quality at high productivity with consistent drop volumes, drop speeds, and drop trajectories. Because the SPT process can define and produce very small physical features, ink filters can be placed in the ink supply for each drop generator. These are seen as pillars in the figure. Integral ink filters improve printhead reliability by preventing unwanted particles in the ink from clogging the drop generators. The epoxy materials used in SPT resist chemical interaction with aqueous inks to give reliable performance and long operational life in commercial print production environments. HP s portfolio of HP Designjet printers with aqueous inks and HP Latex Inks is based on two SPT platforms: printheads with 0.88-inch and 4.25-inch nozzle arrays. These are described in the following table. HP Designjet Printer Array Length Number of Colors/Printhead Ink Type Colors Drop Volumes (pl) Nozzles per Color 69 Total Nozzles HP 70 / HP HP 91 HP 72 HP 789 HP 786 Z2100, Z3200 Z in in. / 1.70 in 64 T610, T620, T770,T1100, T1200 L in in./ 1.70 in 64 L in HP Vivera pigment inks C lc M lm Y lg G pk mk R Gn B E HP Vivera pigment inks C lc M lm Y lg pk mk HP Vivera inks HP Latex Inks HP Latex Inks C M Y pk mk G 66 C lc M lm Y K C lc M lm Y K 4, , , ,056 1,056 1,056 1,056 5,280 Z2100: 8,448; Z3200: 12,672 Nozzles per Inch 1,200 16,896 6,336 12,792 31,680 In addition to the thermal inkjet structure built on silicon die, printhead also describes complete assembly that includes the drop ejecting component mounted on a backend that provides ink pressure regulation, electrical interconnection, ink supply, and mechanical registration. Printheads printing two colors of ink have two independent pressure regulators in the backend assembly. HP Thermal Inkjet printheads feature a snap-out/snap-in design for simple and quick user replacement requiring no tools, handling of ink tubes, or a time-consuming and expensive service call. Inserting the printhead into its slot in the printer carriage makes ink and electrical connections and registers the printhead against mechanical stops. HP s T-, Z-, and L-series Designjet printers print a test plot whenever a printhead is replaced, and the plot is automatically scanned by an optical sensor on the print carriage to perform an automatic color-to-color alignment without requiring manual mechanical adjustments. 62 For example, an HP 70 Thermal Inkjet printhead has 2,112 nozzles on a single die. 63 See the Printer Data Sheet for the printheads and ink colors available for in each printer. 64 Effective print swath with overlap between sets of printheads in HP Double Swath technology. 65 Effective print swath with overlap between printhead chips. 66 Matte Black (mk) is pigment-based; Photo Black (pk), Gray (G), and C, M, and Y inks are dye-based. 67 Drop volumes for the HP 70, HP 73, and HP 91 printheads: 4pl for lc, lm, lg, pk, G, and E; 6pl for C, M, Y, mk, R, Gn, and B. 68 Drop volumes for the HP 72 printheads: 6pl for C, M, pk, and G; 9pl for Y and mk. 69 Nozzles per color on each printhead. Total nozzles per printhead is Number of Colors/Printhead X Nozzles per Color. 22

23 The figure below shows examples of HP s 0.88-inch (left) and 4.25-inch (right) SPT-based printheads. The 4.25-inch printhead has two columns of 5,280 nozzles per color giving 10,560 nozzles on each printhead. With their modular, snapout/snap-in design, a user can remove a used HP Thermal Inkjet printhead from an HP Designjet printer and install a new one in minutes without the expense, printer down-time, and inconvenience of a service call. HP Designjet Z- and T-series Printers HP Designjet Z2100 Printers use HP 70 Printheads. HP Designjet Z3200 Printers use HP 70 Printheads and the HP 73 Printhead with HP 73 Chromatic Red Ink. Each HP 70 and HP 73 Printhead delivers two colors of ink. Because cyan is used in HP Designjet Z2100 Printers and not in HP Designjet Z3200 Printers, matte black and cyan inks are supplied together in an HP 70 Printhead for HP Designjet Z2100 Printers and matte black is paired with chromatic red ink in the HP 73 Printhead for HP Designjet Z3200 Printers. The HP Designjet Z2100 Printer can produce up to 17 ft2/hr (1.58 m2/hr) in Best Mode on glossy paper or a D/A1 print in about 15 minutes.70 HP 91 Printheads were developed for HP Designjet Z6100 Printers to meet the demands of commercial print production environments.71 HP 91 Printheads offer high printing speeds, high reliability, and long service life. Each HP 91 Printhead delivers two colors of ink. Two sets of four HP 91 Printheads are used in a tandem arrangement called HP Double Swath technology in HP Designjet Z3200 Printers. HP Double Swath technology produces a print swath 2,040 nozzles wide.72 An HP Designjet Z6100 Printer can produce up to 98 ft2/hr (9.1 m2/hr) on glossy paper or a D/A1 print in about 5 minutes.73 HP Designjet T-series printers use three HP 72 Printheads for a total of 6,336 nozzles in a 0.88-inch (22.35mm) print swath. Each HP 72 Printhead delivers two colors of ink (gray/photo black, matte black/yellow, and magenta/cyan) with 1,056 nozzles per color. HP 72 Printheads enable HP Designjet T-series printers to deliver high productivity in all print modes. In Fast Mode, an HP Designjet T1100 Printer can produce 52 D/A1 drawings per hour on plain media and 445 ft2/h (41.3 m2/hr) on coated media. Using HP 72 Vivera Matte Black ink, HP 72 Printheads produce fine black lines on HP Matte Film.74 HP Designjet L25500 and HP Designjet L65500 Printers with HP Latex Inks Two sets of three HP 789 Designjet Printheads are used with HP Double Swath technology in the HP Designjet L25500 Printer. Each printhead prints two colors of ink. The HP Designjet L25500 Printer can produce up to 246 ft2/hr (22.8 m2/hr) in 4-pass bi-directional printing ( bi-di ) mode, up to 97 ft2/hr (9.0 m2/hr) in 10-pass bi-di mode, and up to 81 ft2/hr (7.6 m2/hr) in 12-pass bi-di mode.75 Three HP 786 Designjet Printheads are used in a staggered configuration in the HP Designjet L65500 Printer. The printheads overlap by 50% of their swath height to produce a print swath 8.5 inches wide. Color image on glossy paper. On coated paper, up to 31 ft2/h (2.88 m2/hr) and 8.8 minutes for D/A1 in Best Mode. HP 91 printheads are not interchangeable with HP 70 printheads. 72 For HP Double Swath Technology, the top and bottom swaths overlap by 72 dot rows (nozzles). 73 Mechanical printing time on a 60-inch model for a color image on glossy paper. On coated paper, up to 147 ft2/hr (13.6 m2/hr) and 3.3 minutes for D/A1 in Best Mode. 74 See Product Data Sheets for line width specifications for HP Designjet T-series printers. 75 Printed in a 60-in printer, full width plot (60x60in), using HP Permanent Gloss Adhesive Vinyl and Onyx RIP

24 This configuration is called HP Wide Scan Technology. HP Wide Scan Technology delivers high productivity at high image quality by combining a wide print swath with precision control of substrate motion through the print zone using HP s Optical Media Advance Sensor. 76 Each printhead prints two colors of ink in a swath 4.25 inches (108mm) wide with 5,280 nozzles per color. As seen in the previous figure, these wide printheads are made by precisely placing and aligning five (5) printhead die on a ceramic substrate, called a multilayer ceramic module. This ceramic material gives precise die-to-die alignment on a dimensionally-stable, flat, and rigid surface. A small overlap between the nozzle arrays of neighboring die reduces visible print quality effects from variations between the die. High density circuitry built with SPT processes on the printhead die allows the 10,560 nozzles on an HP 786 Designjet Printhead to be operated with only 76 electrical interconnections to the printer. Reducing the number of electrical connections makes a significant contribution to printer reliability. In a 2-pass, full-width (2.64 m/104 in.) unidirectional print mode, this writing system produces up to 846 ft 2 /hr (79 m 2 /hr) of dry, ready-to-use outdoor-quality prints. 77 In a 5-pass, full-width (104 in./2.64 m) unidirectional print mode, indoor-quality prints are produced at speeds up to 368 ft 2 /hr (34 m 2 /hr). 78 Piezoelectric Printheads HP uses OEM piezoelectric printheads for solvent and UV-curable inks in a number of different HP Designjet and HP Scitex printers. Proprietary Aprion printheads are used with aqueous inks in HP Scitex FB6700 Printers. HP Scitex X2 Printheads are used with UV-curable inks in HP Scitex FB7500 Printers. Aqueous Inks Solvent Inks UV-curable Inks HP Scitex FB6700 (with Aprion printheads) HP Designjet 8000sr-, 9000s-, and 10000s HP Scitex TJ8350, XL1200, XL1500 HP Designjet H and H45000-series HP Scitex FB950, FB6100/6050, TJ8550, XP2100, XP2750, XP5100, XP5300 HP Scitex FB7500 (with HP Scitex X2 printheads) For imaging performance and operational reliability, Original HP inks have been developed for use in these printheads. In the development and testing of printers and inks as a system, HP engineers develop custom, optimized operating settings for OEM printheads to achieve the best performance. HP Scitex X2 Piezo Printheads The HP Scitex X2 printhead is shown in this figure placed next to an ordinary pencil to give a sense of its compact size. This printhead was developed by HP Scitex and was introduced in HP Scitex FB7500 Printers with UV-curable inks. Offering 100 nozzles per inch and a small footprint in the print zone (8 X 64 mm), HP Scitex X2 printheads are designed to be assembled into arrays to make a compound industrial inkjet printhead with a higher native resolution (i.e., nozzles per inch) and wider swath. For example, the basic element of a 400 dpi printhead (for each color) would use four HP Scitex X2 printheads stacked together and offset by 1/400-inch. Wider print swaths can be made by stacking these elements across the scan direction. 76 The HP Optical Media Advance Sensor was introduced with HP Designjet Z6100 Printers. 77 Printers using HP Latex Inks use internal heaters to dry and cure the latex polymer film pass print mode is only available on self-adhesive vinyl substrates. 24

25 The HP Scitex X2 printhead is built with integrated circuit precision using silicon-based MEMS technologies.79 With its ability to produce features on a sub-micron scale, MEMS allows the shape of nozzles and ink channels to be optimized for an ink s physical properties for high performance drop ejection. MEMS produces drop generators with uniform characteristics across each printhead and from printhead to printhead, and this allows arrays of HP Scitex X2 printheads to deliver consistent drop volumes and velocities with high placement accuracy. The HP Scitex X2 printhead consists of three major subassemblies: the Printhead Chip, the Chip Holder, and the Electronics Package. These are seen in an exploded view in this figure. The Printhead Chip features a two-sided side-shooter design nozzles, ink channels, and piezo actuators are formed on each side of a silicon chip. Each printhead delivers a single color of ink using 128 nozzles spaced at 100 nozzles per inch. A very thin, flexible glass plate is bonded to each side of the silicon chip to seal the ink channels. A piezo actuator and electrodes are deposited above each ink channel on the outside surface of the glass. This design completely isolates these electrical components from ink contact for long life and reliability. Each piezo actuator deflects the glass plate a fraction of a micron into its ink channel when a voltage pulse is applied. This ejects an ink droplet. The nominal drop velocity of 8 meters/sec is designed for precise dot placement at linear printing speeds up to 2 meters per second. The Chip Holder is the assembly that holds and aligns the Printhead Chip, locates and mounts the printhead in the printer, connects to the ink supply, provides an ink distribution manifold, and supports a flexcircuit that connects the Printhead Chip to the Electronics Package. With two ink ports, the ink supply can be designed so that ink flows across the manifold to purge bubbles. Two ports also minimize pressure drop at high ink flow rates: each HP Scitex X2 printhead can deliver up to 10 ml of ink per minute.81 The Electronics Package processes printhead control signals, regulates voltages, and drives the piezo actuators. It contains two identical electronic assemblies, one each for the top and bottom arrays of 64 nozzles. In an industrial inkjet printer with many printheads, convenient installation and maintenance of individual printheads is an important design consideration. The HP Scitex X2 printhead features mechanical, ink, and electrical connections that allow the printhead to be plugged into place and secured by two screws. Two mechanical locator pins provide better than 10-micron positioning accuracy without adjustment. Ink connections are made through ports sealed with an O-ring, so there are no ink tubes to attach and tighten. Electrical power and control signals come through a standard 26-pin connector. By design, HP Scitex X2 printheads offer high chemical resistance to industrial inkjet inks. This is because only silicon, glass and epoxy touch the ink, and the piezo actuators and electrodes are completely isolated from ink exposure. MEMS is an acronym for MicroElectroMechanical System. MEMS photolithographic and chemical etching processes produce ink channels and nozzles in silicon. Side-shooter means the ink drops are ejected in the plane of the chip. 81 Ink flow rate for comparative purposes based on the product of drop volume, drop ejection frequency, and number of nozzles. Actual ink delivery in operation depends on print mode, media, and other factors

26 Key specifications for HP Scitex X2 printhead are summarized in the table below: HP Scitex X2 Printhead Array Length 1.28 in Number of Inks/Printhead 1 Inks UV-curable Drop Volumes (pl) up to 50 Total Nozzles 128 Nozzles Per Inch 100 Summary There are many factors to consider when choosing an HP commercial or industrial printing solution. Each HP ink technology has unique features and satisfies different requirements. Choosing the type of ink (aqueous, solvent, or UV-curable) is generally not the starting point for determining a printing solution that will best meet the needs of your business. Rather, the selection of an ink technology, ink formulations, and printing hardware results from a detailed evaluation of your needs in consultation with your HP Large Format Sales Engineer. This process will consider factors such as: applications and application versatility durability and display permanence acquisition price odorless prints production cost media versatility projected print volume need to print on low-cost, uncoated vinyl image quality environmental impact of printing print format HP s broad commercial and industrial printing portfolio spans applications, ink technologies, formats, and production volumes to provide your print production business with the solutions you need. For more information To learn more about HP s commercial and industrial ink technologies, visit Hewlett-Packard Development Company, L.P. The information contained herein is subject to change without notice. The only warranties for HP products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. HP shall not be liable for technical or editorial errors or omissions contained herein. July 2009 Revision 3 26