Printing Inks. Druckfarben_GB_2012_final.indd :04

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1 Printing Inks Druckfarben_GB_2012_final.indd :04

2 Masthead Published by Evonik Industries AG Goldschmidtstraße Essen Germany Managing Editor (responsible) Susanne Struck Contact Design MERZ Werbeagentur, Düsseldorf Translation Dr. John Haim, Christopher Howard Copyright The editorial matter, pictures or text, may not be reproduced without the publisher s prior permission. Druckfarben_GB_2012_final.indd :05

3 About us TEGO one of the successful brands from Evonik Industries As the leading supplier of specialty chemicals world-wide, Evonik offers its customers in the coatings industry a unique range of products under the TEGO brand name. Our portfolio is the result of experience gained over 25 years in which we have researched optimal solutions which are ideal for our customers. With more than 200 products, the range currently includes not only defoamers and deaerators but also wetting and dispersing additives, flow additives, radiation-curing additives, rheological additives, hydrophobing agents and even co-binders, specialty resins, and nanocomposites. We remove air from paint, make surfaces glossy and ensure lacquers are scratch-resistant. Environmental concerns are of key importance when developing our new products. Besides our extensive expertise in providing customized solutions, our numerous contacts in more than 40 countries are an additional advantage. This underlines our philosophy of developing intelligent products for new applications not only for, but together with, our customers. We look forward to your challenge and are confident that we can find an advantageous solution for you. Tego Adding Advantages. TEGO Printing Inks Seite 3 Druckfarben_GB_2012_final.indd :05

4 TEGO Dispers Wetting and dispersing additives TEGO Foamex und Airex Defoamers and deaerators TEGO Flow und Glide Flow and slip additives TEGO Rad Cross-linkable surface control additives for radiation curing TEGO Wet Substrate wetting additives TEGO Phobe Hydrophobing agents TEGO VariPlus Co-binders Know-how Evonik s TEGO brand name stands for innovation in the development of new binders, co-binders and special-purpose binders. Combating micro- and macro-foam continues to be a major focus. For more than 20 years, the TEGO product range has included polyethersiloxane copolymers. Emulsions manufactured from them are used as high-performance defoamers for waterborne flexographic and gravure printing inks as well as overprint varnishes. With the TEGO range of products, Evonik has been firmly established for many years as a supplier of cross-linkable surface control additives (silicone acrylates) for radiation-curing printing inks and varnishes. Highly dynamic, silicone-free wetting additives for waterborne printing inks, lacquers and fountain solution concentrates as well as wetting and dispersing agents for waterbornes and UV have become important in recent years. Co-binders for improving adhesion and general film properties are also considered. Seite 4 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

5 The focus At Evonik, the main emphasis in new product development is on waterborne and energy-curing printing inks and varnishes. The strong focus on future coatings and printing inks technologies has resulted in practically all Tego additives for the printing inks industry being free of organic solvents, mineral oils, silicone oils and alkylphenol ethoxylates. The brochure Our printing ink market segment brochure is intended to facilitate your daily formulation tasks and also provide a comprehensive overview of our products for printing inks and varnishes. This brochure provides valuable information and product recommendations which will help you solve problems rapidly. It is arranged as follows: Proximity to customers A large team of specialists is concerned solely with evaluating and supporting TEGO additives for printing inks and varnishes. This takes place in close consultation with our specially trained marketing specialists, the international Technical Competence Center and above all with you, our customers. The future Our strength is being able to think one step ahead. Evonik is constantly working on developing new and improved technologies for the wide spectrum of additives and co-binders discussed here. Flexographic and gravure printing inks * 6-13 Printing varnishes Silk screen printing inks and varnishes Industrial inkjet * The demands made on additives for gravure and flexographic inks are often similar and are thus discussed jointly in one section. TEGO Printing Inks Seite 5 Druckfarben_GB_2012_final.indd :05

6 Flexographic- and Gravure Printing Inks Druckfarben_GB_2012_final.indd :05

7 Because of their low viscosity, flexographic and gravure printing inks make particular demands on the additives used. First, high pigment loadings (usually organic pigments or carbon blacks) must be optimally wetted and stabilized. Second, the inks must be very efficiently defoamed, an increasingly difficult task with the ever higher machine speeds and new doctor blade systems. Rapid foam collapse is more and more often required, and the additives must be highly resistant to shear. Widely differing print stock must, of course, be rapidly and efficiently wetted. Finally, suitable additives can be used to customize the surface properties of flexographic inks. TEGO Printing Inks Seite 7 Druckfarben_GB_2012_final.indd :05

8 TEGO Dispers 760 W aqueous wetting and dispersing additive outstanding color intensity and rheology effective at low concentrations outstanding for carbon blacks and organic pigments suitable for binder-containing pigment concentrates especially suitable for flexographic and gravure printing inks TEGO Dispers 685 high performance wetting and dispersing additive outstanding viscosity reduction and color intensity outstanding for carbon blacks and organic pigments very suitable for titanium dioxide ideal for UV-flexographic inks Wetting and dispersing additives for waterborne flexographic and gravure printing inks When manufacturing waterborne flexographic and gravure printing inks, pigment grinding can take place in aqueous resin solution or without binder, i.e. without resin solution. Depending on the process chosen, differing demands are made on the wetting and dispersing additives. If the pigment is ground in an aqueous resin solution, the wetting and dispersing additive should exhibit first class pigment wetting characteristics. This is necessary in order to have a strong effect on the flow of the millbase, color strength development and transparency even at relatively low concentrations. Evonik has developed the highly effective TEGO Dispers 760 W for this purpose. For binder-free pigment grinding (without resin solution), excellent stabilization of the pigment dispersion is also required. TEGO Dispers 765 W, a polymer wetting and dispersing additive, was specially developed for use in binder-free printing inks. TEGO Dispers 653 is particularly suited for use with phthalocyanine pigments either on its own or in combination with TEGO Dispers 765 W. Both products are also distinguished by good pigment wetting properties and outstanding pigment stabilization thus permitting the manufacture of stable aqueous pigment concentrates with excellent color intensity and highly stable viscosity. Larger amounts of additives are required in this case because there is no resin solution additionally stabilizing the pigments. Seite 8 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

9 Wetting and dispersing additives for radiation-curing flexographic inks Rheology is often the greatest challenge in the case of radiation-curing flexographic inks because of the high pigment loadings required. When using a solventfree additive in such printing inks, high performance additives are necessary to obtain sufficiently good flow properties and excellent color strength development especially with problematical pigment surfaces. TEGO Dispers 685, specially developed for this purpose, is a liquid, high molecular weight wetting and dispersing additive optimally suited for both organic carbon blacks and titanium dioxide. In addition to good pigment wetting, TEGO Dispers 685 increases gloss. The product is equally suited for grinding in triple roll mills and bead mills. Improving grinding by the use of special resins in solventborne printing inks To maintain a competitive advantage, manufacturers strive constantly to improve their solventborne, and particularly nitrocellulose-based, printing inks. Evonik has a product for improving pigment wetting and stabilization: TEGO VariPlus TC, a ketone-aldehyde condensation resin which functions as a cobinder and is incorporated during the grinding process. The strong pigment affinity of this co-binder results in higher color intensities and lower viscosities in the millbase. TEGO VariPlus TC improves adhesion of the printing ink even on difficult substrates such as polyolefins. Millbase defoamers: also effective in the finished printing inks The millbase defoamer contributes decisively to efficient pigment dispersing. Poor defoaming of the millbase results in inadequate transfer of the applied shear forces to the millbase because of the foam. An effective defoamer in the millbase ensures short dispersing times and the best possible dispersing result after let-down of the millbase. It also ensures basic defoaming in the finished flexographic or gravure printing ink. Pigment dispersion Organic pigments Carbon blacks Inorganic pigments binder-containing pigment dispersion TEGO Dispers 760 W TEGO Dispers 765 W TEGO Dispers 760 W TEGO Dispers 765 W TEGO Dispers 755 W TEGO Dispers 760 W TEGO Wet 505 TEGO Dispers 653 binder-free pigment dispersion TEGO Dispers 765 W TEGO Dispers 653 TEGO Dispers 765 W TEGO Dispers 760 W TEGO Dispers 750 W TEGO Dispers 755 W TEGO Dispers 653 TEGO Dispers 752 W TEGO Dispers 685 TEGO Dispers 710 TEGO Dispers 685 TEGO Dispers 710 TEGO Dispers 685 TEGO Dispers 656 TEGO Dispers 652 Solventborne binder-containing pigment dispersion TEGO VariPlus TC TEGO VariPlus TC TEGO Printing Inks Seite 9 Druckfarben_GB_2012_final.indd :05

10 The right combination of millbase and let-down defoamer The addition of a high performance defoamer to the let-down is a prerequisite for the persistent, efficient defoaming of a printing ink. It is worthwhile using a combination made up of a millbase defoamer and let-down defoamer. Two different products are frequently used in waterborne flexographic and gravure printing inks: a highly effective defoamer concentrate or defoamer solution for the millbase an easily incorporated defoamer emulsion for the let-down Long-term effectiveness of defoamers Some ink formulations, particularly those based on classical, waterborne hybrids of carboxyl-containing resin solution in combination with a polymer dispersion, seem to rapidly swallow traditional defoamers rendering them ineffective. This effect is frequently reinforced by the use of commercialy available pigment concentrates with a high tendency to foam. In developing defoamers for printing inks in recent years, Evonik has, therefore, placed a strong emphasis on good long-term effectiveness which is reflected in the development of products such as TEGO Foamex 842 and 3062 for the millbase and TEGO Foamex 843, 845 or 1488 for the let-down. There is also an additional focus on the shear stability of the defoamer and rapid foam collapse. Seite 10 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

11 TEGO Foamex 843 defoamer compound rapid foam collapse easily incorporated long-term effectiveness and shear resistant very suitable for colloidal systems very suitable for waterborne flexographic and gravure printing inks Silicone-free defoamers Besides organic modified polysiloxanes, Evonik also offers silicone-free products. Developed for waterborne printing inks, TEGO Foamex 831 is very good at defoaming millbases. It is also well suited for use in the let-down in the most diverse formulations. For particularly sensitive systems, TEGO Foamex 830 has proved to be a highly compatible millbase defoamer. In UV flexographic inks, the silicone- and solvent-free TEGO Airex 920 is a good and highly compatible defoamer in both the millbase and letdown. Defoaming absorbent print stock Millbase TEGO Foamex 842 TEGO Foamex 810 TEGO Airex 901 W TEGO Foamex 831 silicone-free defoamer good foam inhibition and collapse good effectiveness in millbase and let-down ideal for use in printing inks for food packaging Let-down TEGO Foamex 843 TEGO Foamex 845 TEGO Foamex 1488 non-absorbent print stock Solventborne TEGO Foamex 810 TEGO Foamex 830 TEGO Foamex 831 TEGO Airex 920 TEGO Airex 900 TEGO Foamex N TEGO Airex 900 TEGO Foamex N TEGO Foamex 822 TEGO Foamex 805 TEGO Airex 902 W TEGO Airex 920 TEGO Rad 2500 TEGO Airex 920 TEGO Airex 900 TEGO Printing Inks Seite 11 Druckfarben_GB_2012_final.indd :05

12 TEGO Wet 500 silicone-free substrate wetting additive outstanding dynamic properties foam inhibiting universally applicable in waterborne printing inks and varnishes TEGO Twin 4100 Siloxane-Gemini surfactant very good substrate wetting without stabilizing foam wetting even on the most difficult substrates suitable for waterborne printing inks and varnishes Substrate wetting and flow Rapid printing processes require rapid wetting With most high speed printing machinery, good and rapid wetting of the print stock by the printing ink is essential. Substrate wetting additives not only promote wetting but also assist as a suitable additive during transfer of the printing ink from the printing cylinder or plate to the substrate. In waterborne flexographic or gravure printing inks, highly dynamic surfactants such as the TEGO Wet 5XX range are the first choice. These solventfree, non-ionic wetting additives not only promote wetting of diverse substrates but also inhibit foam. A strong reduction of the static surface tension is important to ensure good wetting of even difficult substrates. Furthermore, fast machine speeds and processes increase foam build-up. TEGO Twin 4000 and 4100, members of a new class of product developed specifically by Evonik to combat this, are siloxane-based Gemini surfactants. This unique technology impressively combines substrate wetting and foam inhibition up to foam collapse. TEGO Twin 4000 and 4100 are modern multifunctional additives effective in low concentrations in waterborne and radiation-curing printing inks. Combinations of organic and siloxanebased surfactants are also promising as they exhibit high dynamics resulting in good ink transfer and good lay-down on difficult substrates. With very difficult to wet print stock, such as polyolefins, the use of a classic siloxane surfactant is recommended. TEGO Wet 270 or TEGO Twin 4100 are particularly suitable. paper, card, corrugated cardboard, etc. PE, PP, etc. aluminum, etc. Solventborne TEGO Wet 500 TEGO Wet 505 TEGO Twin 4100 TEGO Wet 270 * TEGO Twin 4100 * TEGO Wet 510 TEGO Wet 270 * TEGO Wet 510 TEGO Twin 4100 TEGO Glide 435 TEGO Wet 270 TEGO Rad 2300 TEGO Glide 100 TEGO Glide 410 TEGO Twin 4000 * also in combination with TEGO Wet 500 Seite 12 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

13 Co-binders for improving adhesion on polyolefin substrates Achieving good adhesion is a major challenge, particularly on difficult substrates such as plastic films. A very promising starting point is the use of special co-binders to improve the adhesion and general properties of printing inks. For this, Evonik offers special purpose resins which are simply added to printing ink formulations as co-binders. In solventborne printing inks, the high performance products TEGO VariPlus 1201 and TEGO VariPlus SK have proved especially effective. TEGO VariPlus 1201 improves adhesion, gloss, drying times and chemical resistance. TEGO VariPlus SK additionally produces higher color intensity. The over-printability or embossability of the products is not affected. Surface effects Slip Anti-blocking and release Hydrophobing Slip Anti-blocking and release TEGO Glide 482 TEGO Glide 440 TEGO Glide 410 TEGO Glide 482 TEGO Phobe 1401 TEGO Phobe 1650 TEGO Glide 482 TEGO Phobe 1401 TEGO Glide 432 TEGO Rad 2300 TEGO Glide 435 TEGO Rad 2500 TEGO Rad 2600 TEGO Rad 2700 TEGO Printing Inks Seite 13 Druckfarben_GB_2012_final.indd :48

14 Print Varnishes Druckfarben_GB_2012_final.indd :05

15 Important parameters, as far as additives for printing varnishes or overprint varnishes are concerned, are flow and substrate wetting. Defoaming is also of great importance in as much as it must be achieved without cloudiness, flow problems or impaired gloss. Scratch resistance, anti-blocking and release effects, excellent heat-sealability, bondability, etc. are among the many requirements. These properties are sometimes mutually exclusive and compromises are, therefore, sometimes unavoidable. TEGO Printing Inks Seite 15 Druckfarben_GB_2012_final.indd :05

16 Polysiloxanes optimize slip and antiblocking effect In many applications of printing varnishes, slip and the related increase in scratch resistance and an anti-blocking effect are desired. These effects can be adjusted precisely by high performance siloxanebased surface control additives. In contrast to waxes, they maintain the brilliance and gloss of the printed material. They are frequently used in combination with waxes which results in synergies. The amount of wax required can often be significantly reduced thus increasing gloss while retaining the abrasion-reducing effect of the wax. TEGO Glide 482 has been developed to provide maximum slip and anti-blocking, especially in waterborne formulations. This emulsion of a high molecular polysiloxane produces an outstanding, persistent effect as well as being hydrophobing. The top product for solventborne and particularly nitrocellulose printing varnishes and inks is TEGO Glide A 115. TEGO Glide 410 is particularly suitable for all other solventborne printing ink formulations. Both additives are highly effective and exhibit not only outstanding flow, slip and anti-blocking effects but also improve the effectiveness of waxes and matting agents through uniform orientation. Cross-linkable and non-cross-linkable additives for radiation-curing The TEGO Rad range has been designed to provide persistent surface effects in radiation-curing varnishes. The acrylic groups of these surface control additives cross-link during radiation-curing in the varnish film. For high gloss printing varnishes, we recommend the new, particularly low-foam TEGO Rad 2010 and the highly compatible TEGO Rad Both promote highly effective substrate wetting, flow, slip and scratch resistance. TEGO Rad 2500 is especially suitable for matted printing lacquers. Besides improving slip, scratch resistance and anti-blocking, it also deaerates. If cross-linkability of the surface control additive is not required, the desired effect can be achieved with non-reactive polyether siloxane copolymers such as TEGO Glide 432 or 440. Seite 16 TEGO Printing Inks Druckfarben_GB_2012_final.indd :49

17 The highest cross-linkability is achieved with both new products in the TEGO Rad range. TEGO Rad 2010 is particularly low-foam, improves wetting and lowers the slip value. Nevertheless, it is so compatible that it can be used in radiation-curing printing varnishes and printing inks. TEGO Rad 2011 is overprintable and improves the flow of an ink or overprint varnish. These products are also of interest for their process simplification which results in an outstandingly good cost/performance ratio. Bondability and heat sealability In many cases, the emphasis with printing lacquer formulations is that they should be bondable and heat sealable, and this is somewhat at odds with slip and release. This requires non-reactive surface control additives, the slip effect of which is somewhat less pronounced than that of the products mentioned above. TEGO Glide 100 provides the ideal balance between slip and heat-sealability and is equally suited for use in waterborne, radiationcuring and solventborne formulations. It also improves flow. Surface effects Flow Slip Anti-blocking and release Hydrophobing Flow, non-reactive Flow, reactive Slip, non-reactive Slip, reactive Anti-blocking and release General TEGO Glide 440 TEGO Wet 500 TEGO Flow 425 Bondable and heat-sealable TEGO Wet 270 TEGO Wet 510 TEGO Glide 482 TEGO Glide 410 TEGO Glide 440 TEGO Glide 100 TEGO Glide 482 TEGO Phobe 1401 TEGO Glide 410 n. a. TEGO Glide 482 TEGO Phobe 1401 TEGO Phobe 1650 n. a. TEGO Glide 432 TEGO Flow 425 TEGO Glide 440 TEGO Rad 2010 TEGO Rad 2300 TEGO Rad 2250 TEGO Wet 270 TEGO Flow 425 TEGO Wet 500 TEGO Rad 2100 TEGO Rad 2011 TEGO Glide 432 TEGO Glide 440 TEGO Glide 435 TEGO Glide 100 TEGO Rad 2250 TEGO Rad 2010 TEGO Rad 2500 n. a. TEGO Rad 2500 TEGO Rad 2700 * TEGO Rad 2010 n. a. TEGO Glide 482 slip additive emulsion outstanding slip and release effect maintains gloss and flow ideal for waterborne printing varnishes, also suitable for pigmented inks TEGO Rad 2010 radiation-curing surface control additive highest cross-linkability promotes wetting, flow and slip particularly low-foam ideal for printing varnishes, also suitable for pigmented inks * if necessary, in combination with TEGO Rad 2200 N or TEGO Glide 440 TEGO Printing Inks Seite 17 Druckfarben_GB_2012_final.indd :05

18 TEGO Twin 4000 siloxane-based Gemini surfactant highly effective at low concentrations very good wetting particularly recommended for waterborne overprint varnishes defoaming effect TEGO Wet 510 silicone-free substrate wetting additive very good substrate wetting and flow no foam stabilization improves gloss ideal for waterborne printing varnishes Substrate wetting and flow a manyfaceted challenge Printing and overprinting varnishes are applied to a wide variety of substrates, and the range of substrate wetting additives used is just as diverse. Sulfosuccinate surfactants have been used in waterborne formulations to ensure adequate wettability by the overprint varnish of the fresh offset ink. Within the Tego Select Line range, Evonik offers for such applications a diisooctyl sulfosuccinate under the names Rewopol SB DO 75 and SB DO 75 PG. A disadvantage of the sulfosuccinates is, however, foam build-up which occurs during the production or application of waterborne lacquers. Evonik has developed a new class of additives to deal with this; the siloxane-based Gemini surfactants TEGO Twin 4000 and TEGO Twin 4000, in particular, exhibits outstanding properties in waterborne overprint varnishes when wetting fresh offset inks. It is both substrate-wetting and foam-inhibiting to defoaming. Even small amounts reduce the number of products required in the combination of defoamers, flow additives and substrate wetting additives previously necessary. The use of a single additive improves the result. Tests and experience show that this technology can completely eliminate the need to use strongly foaming organic surfactants in waterborne printing lacquers. TEGO Twin 4100 greatly improves wetting of difficult substrates, such as polyolefins, by waterborne printing inks. The combination of substrate wetting without foaming makes it significantly easier for the development chemist to develop formulations for fast-running machines. With radiation-curing overprint varnishes, this challenge can be mastered with very strongly surface-active polyether siloxanes or polyether siloxane acrylates. TEGO Glide 432 is the favorite for this application. Besides substrate wetting, it also ensures good flow and high slip. Similar properties, paired with cross-linkability, can be achieved with TEGO Rad Substrate wetting Fresh offset inks Paper, cardboard Aluminum, plastic foil, etc. Non-reactive Reactive General * also in combination with TEGO Wet 500 TEGO Twin 4000 TEGO Wet 270 * Rewopol SB DO 75 TEGO Twin 4100 TEGO Wet 510 TEGO Wet 500 TEGO Wet 270 * TEGO Wet 510 TEGO Twin 4100 * TEGO Glide 432 TEGO Glide 435 TEGO Glide 440 Bondable and heat-sealable TEGO Wet 270 TEGO Wet 500 TEGO Rad 2250 TEGO Rad 2010 TEGO Rad 2200 N TEGO Rad 2100 If, in contrast, slip should be avoided, TEGO Wet 270 or the cross-linkable TEGO Rad 2010 is the product of choice. Both maintain the heat-sealability and bondability of the ink surface. In other applications, such as waterborne printing varnishes on aluminum, both the highly active siloxane surfactants and the broadly applicable low-foam and dynamic silicone-free surfactants of the Tego product range are used. Here, TEGO Wet 510, the most hydrophilic representative of the TEGO Wet 5XX range, has proved to be particularly effective. TEGO Wet 510 exhibits, besides good substrate wetting, excellent flow properties and improved gloss. Seite 18 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

19 Optimal choice and incorporation of defoamers and deaerators Depending on their formulation and viscosity, printing varnishes exhibit very different foaming behavior. Many overprint varnishes contain high amounts of surfactant for substrate wetting and exhibit a high level of foam stabilization. Therefore, they require highly active defoamers. Other formulations, in contrast, require only very compatible defoamers. Depending on the application process, there can be many types of foam. The higher viscosity formulations, such as those for roller application, frequently tend to experience stable micro-foam. Defoamers or deaerator concentrates are ideally suited to eliminate this. In contrast, gravure lacquers usually require defoamers with good compatibility and rapid foam collapse. With all printing varnishes, it is essential for the defoamer/deaerator to be mixed in thoroughly to avoid flow problems in the finished varnish. In waterborne formulations, defoamer emulsions are therefore predominantly used because they require lower shear forces to incorporate them than concentrates. Pre-dilution in suitable solvents and/or the use of high shear is recommended for incorporating defoamers and deaerator concentrates. The high activity defoamer emulsion TEGO Foamex 845 is excellently suited for waterborne overprint varnishes with a strong tendency to foam. For lower foam and also more defectprone printing varnishes, TEGO Foamex 805 and TEGO Airex 902 W defoamer emulsions, which are optimized for compatibility, are preferred. The highly compatible TEGO Airex 920 has been specially developed for non-pigmented radiation-curing formulations and is ideal for UV varnishes. It introduces almost no cloudiness or tendency towards defects in the varnish and maintains its heat-sealability and bondability. Defoaming glossy matte Strong foaming TEGO Foamex 845 TEGO Airex 901 W TEGO Foamex 822 TEGO Rad 2011 radiation-curing surface control additive highly cross-linkable overprintable promotes flow TEGO Rad 2500 radiation-curing surface control additive defoaming and deaerating effect increases slip and scratch resistance ideally suited for matted lacquers and screen printing inks Moderate foaming TEGO Airex 902 W TEGO Foamex 822 TEGO Foamex 805 TEGO Airex 920 TEGO Rad 2500 TEGO Airex 900 TEGO Airex 920 TEGO Rad 2500 TEGO Airex 900 TEGO Airex 920 TEGO Airex 920 TEGO Rad 2500 TEGO Printing Inks Seite 19 Druckfarben_GB_2012_final.indd :05

20 Screen Printing Inks and Varnishes Druckfarben_GB_2012_final.indd :05

21 Screen printing inks and varnishes make the highest demands on the effectiveness of deaerators. The reason is that during printing, large amounts of finely dispersed air are introduced into the ink film as micro-foam. The relatively high film thicknesses and the rheology of inks and varnishes make it difficult for the foam to escape. The diversity of the pigments used in screen printing can lead to various problems in pigment wetting and stabilization. Of course, high performance additives are required to wet the hugely different print stock such as plastics, metals, glass, etc and obtain pronounced surface effects such as slip, release, etc. TEGO Printing Inks Seite 21 Druckfarben_GB_2012_final.indd :05

22 TEGO Airex 900 very effective defoamer/ deaerator concentrate good balance between foam destruction and compatibility particularly rapid deaeration TEGO Airex 920 silicone-free deaerator concentrate good effectiveness with minimal susceptibility to defects overprintable and bondable ideally suited for radiationcuring printing varnishes and inks Deaerator = Flow and leveling additive? Experience shows that with screen printing, it is difficult to separate defoaming, deaerating and flow from one another. The microfoam introduced during printing is often apparent only in the form of poor flow. This is even truer of the UV screen printing inks and varnishes which cure in seconds and particularly with rotary screen printing. Evonik has therefore developed high performance, siloxanebased defoamers and defoamer concentrates such as TEGO Foamex N and TEGO Airex 900. Both products have an active substance content of 100% and solve even difficult foam problems in radiation-curing and solventborne formulations. If bondability and problem-free overprintability is demanded of radiationcuring formulations, the silicone-free deaerator TEGO Airex 920 is suitable. For waterborne screen printing inks and varnishes, TEGO Airex 901 W is the preferred choice. This is a deaerator concentrate specially developed for combating micro-foam in waterborne formulations. All the products mentioned are solvent-free. TEGO Foamex N extremely effective defoamer concentrate ensures fastest deaeration and foam destruction ideal for pigmented screen printing inks Defoaming Millbase TEGO Foamex 810 TEGO Airex 901 W TEGO Foamex 845 TEGO Foamex N TEGO Airex 900 TEGO Airex 920 Let-down/Clear coat TEGO Foamex 845 TEGO Airex 901 W TEGO Foamex 810 TEGO Airex 920 TEGO Airex 900 Solventborne TEGO Foamex N TEGO Airex 900 TEGO Foamex 840 TEGO Airex 931 TEGO Airex 986 TEGO Airex 935 Seite 22 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

23 Pigment wetting and dispersion It is obvious that not all pigments can be equally well wetted with just one additive. However, to keep the number of wetting and dispersing additives within a range of inks to a minimum, Evonik offers products which are widely applicable. Thus, the polymeric high performance additives, TEGO Dispers 670 and 710, used in solventborne and radiation-curing screen printing inks, can be considered as almost universal additives. They are excel- lently suited for the dispersion of carbon blacks, organic and inorganic pigments. In absolutely solvent-free radiation-curing inks, it is strongly recommended that the choice of wetting and dispersing additive for optimal color strength development should depend on the type of pigment. With the new types, TEGO Dispers 685 and TEGO Dispers 652, Evonik offers solvent-free high performance products for this purpose. For waterborne screen printing inks, there are also widely applicable wetting and dispersing additives: TEGO Dispers 755 W, which shows its strengths particularly in binder-free pigment grinds, and TEGO Dispers 760 W, which in binder-containing grinds provides excellent wetting of the most critical pigments even at very low concentrations. For inorganic pigments and fillers, we particularly recommend TEGO Dispers 653. Of course, all these additives are solvent-free and, like all TEGO additives, free of alkylphenol ethoxylates. Pigment dispersion Organic pigments Carbon blacks Inorganic pigments Binder-containing pigment dispersion TEGO Dispers 760 W TEGO Dispers 653 TEGO Dispers 755 W TEGO Dispers 760 W TEGO Dispers 650 TEGO Dispers 755 W TEGO Dispers 755 W TEGO Wet 505 TEGO Dispers 653 Binder-free pigment dispersion TEGO Dispers 755 W TEGO Dispers 653 TEGO Dispers 760 W TEGO Dispers 755 W TEGO Dispers 760 W TEGO Dispers 650 TEGO Dispers 653 TEGO Dispers 755 W TEGO Dispers 752 W TEGO Dispers 685 TEGO Dispers 710 TEGO Dispers 652 TEGO Dispers 685 TEGO Dispers 670 TEGO Dispers 710 TEGO Dispers 685 TEGO Dispers 710 TEGO Dispers 652 Solventborne TEGO Dispers 670 TEGO Dispers 710 TEGO Dispers 685 TEGO Dispers 710 TEGO Dispers 670 TEGO Dispers 685 TEGO Dispers 700 TEGO Dispers 710 TEGO Dispers 685 TEGO Printing Inks Seite 23 Druckfarben_GB_2012_final.indd :05

24 TEGO Rad 2010 radiation-curing surface control additive highly cross-linkable low foam to defoaming properties improves wetting, slip and anti-blocking high compatibility TEGO Rad 2700 radiation-curing surface control additive produces lowest release and slip values strong hydrophobing and anti-blocking properties very effective even at minimal dosages particularly suitable for printing inks TEGO Glide 435 siloxane-based slip and release additive high compatibility greatly improves wetting and promotes flow low foam very compatible in printing inks and varnishes Surface control additives: preventing foam is also important Very pronounced surface effects are frequently desired in screen printing inks and varnishes. When recommending appropriate additives, Evonik places a strong emphasis not only on their effectiveness but also on their anti-foaming effect. In this respect, the Tego range of products contains some particularly interesting types: The cross-linkable TEGO Rad 2500 is used with great success in radiation-curing screen printing formulations. It combines a durable release effect with surface smoothness and pronounced deaerating characteristics. It is especially suitable for screen printing inks and matte screen printing varnishes. TEGO Rad 2010 (highly cross-linkable) and TEGO Glide 435 are the particularly low-foam yet good compatibility products of first choice for high gloss, radiation-curing varnishes. Both products are strongly substrate-wetting and flow promoting. Surface effects TEGO Glide 482 is the counterpart for waterborne formulations. It achieves maximum possible slip and anti-blocking, does not stabilize foam and is outstandingly suitable for use in a wide range from pigmented inks to high gloss varnishes. Substrate wetting without foam For optimizing substrate wetting in screen printing with waterborne formulations, we recommend TEGO Wet 505, the most hydrophobic member of the TEGO Wet 5XX range. If the product is used in the millbase, it also improves pigment wetting. The additional use of low concentrations of a highly active siloxane surfactant such as TEGO Wet 270 for wetting very low energy materials such as plastic film gives excellent results. The previously described products, TEGO Rad 2010 und 2011 (highly cross-linkable) as well as TEGO Glide 435, are widely applicable in radiation-curing formulations. If their slip effect is, however, General Bondable and heat-sealable Wetting and flow TEGO Wet 505 TEGO Wet 270 TEGO Twin 4100 TEGO Wet 500 TEGO Wet 505 TEGO Wet 270 Slip Anti-blocking and release TEGO Glide 482 TEGO Glide 410 TEGO Glide 440 TEGO Glide 100 TEGO Glide 482 TEGO Phobe 1401 TEGO Phobe 1650 n. a. Hydrophobing TEGO Glide 482 TEGO Phobe 1401 n. a. Seite 24 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

25 Surface effects General, pigmented General, clear Bondable and heat-sealable Wetting and flow, non-reactive TEGO Glide 435 TEGO Wet 270 TEGO Wet 500 TEGO Glide 435 TEGO Glide 432 TEGO Wet 270 TEGO Wet 270 TEGO Wet 500 Wetting and flow, reactive Slip, non-reactive Slip, reactive Anti-blocking and release TEGO Rad 2010 TEGO Rad 2011 TEGO Rad 2200 N TEGO Glide 435 TEGO Glide 432 TEGO Foamex 840 TEGO Rad 2010 TEGO Rad 2500 TEGO Rad 2600 TEGO Rad 2500 TEGO Rad 2700 TEGO Rad 2010 TEGO Rad 2010 TEGO Rad 2250 TEGO Rad 2011 TEGO Rad 2011 TEGO Glide 435 TEGO Glide 432 TEGO Glide 100 TEGO Rad 2010 TEGO Rad 2250 n. a. TEGO Rad 2500 TEGO Rad 2010 n. a. undesirable or heat sealability and bondability are required, then other siloxane additives should be used. The first choice here is TEGO Wet 270. It is effective in lowering surface tension in clear and in pigmented formulations and does not produce any significant slip on the surface. A similarly good result can be achieved with the cross-linkable TEGO Rad Co-Binders for improving adhesion on plastic films Screen printing inks are applied to all sorts of substrates. Good adhesion is of major importance and may be achieved by using co-binders to improve this and other properties of printing inks. For this purpose, Evonik offers specially developed co-binders which are added to printing ink formulations. TEGO VariPlus 1201 and TEGO VariPlus SK have proved themselves in solventborne printing inks. The use of TEGO VariPlus 1201 results in improved adhesion, increased gloss, faster drying and better resistance to chemicals. Additionally, TEGO VariPlus SK achieves higher color intensity. TEGO Printing Inks Seite 25 Druckfarben_GB_2012_final.indd :05

26 Industrial Inkjet Druckfarben_GB_2012_final.indd :05

27 Inkjet inks require a special approach plus high performance additives and co-binders. The difference, and thus the challenge, with solventborne, radiation-curing and waterborne inkjet formulations is their very low viscosity. Typically, it is even less than the very low viscosity of flexographic and gravure inks. Close attention must be paid to pigment wetting and the correct choice of dispersing additive. Extremely fine pigments are being used instead of dyes in contemporary industrial but also, increasingly, SOHO (Small Office Home Office) applications. During dispersion, these extremely fine pigments are frequently ground down into primary particles. The dispersing additive must wet their surfaces quickly, stabilize the pigment and get as close to Newtonian flow as possible. Furthermore, additives control and affect various aspects of the rheology such as drop formation and substrate wetting. TEGO Printing Inks Seite 27 Druckfarben_GB_2012_final.indd :05

28 Wetting and dispersing additives for radiation-curing inkjet inks Pigment wetting and dispersing make their own specific demands. Although the pigment content in inkjet formulations is not high, extremely high performance dispersing additives are required. The design of the print head, highest possible color intensity and Newtonian flow are just some important aspects. The pigments must be dispersed down to primary particle size and stabilized which requires high performance dispersing additives. TEGO Dispers 685 has proved to be an especially useful wetting and dispersing additive in radiation-curing inkjet formulations. Organic pigments and, particularly, magenta and carbon black pigments, are rapidly wetted and durably stabilized. TEGO Dispers 685 works both in formulations based on pure monomer and in monomer/oligomer mixtures. TEGO Dispers 685 also ensures Newtonian flow for the inkjet inks. Seite 28 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

29 Viscosity is less of a problem with solventborne than with radiation-curing inkjet formulations. Nevertheless, very good and rapid dispersion is desirable. The rheological profile should be as Newtonian as possible to preclude problems during printing. The use of TEGO Dispers 670 in this situation enables the desired properties to be achieved. The high molecular weight wetting and dispersing additive is particularly suitable for organic and carbon black pigments for the inkjet sector. TEGO Dispers 670 achieves its outstanding properties in most of the common solvents including eco-solvents. Dispersing additives are particularly important for waterborne inkjet inks. If pigments are used instead of dyes, very powerful additives are required for wetting and controlling rheology. In some cases, siloxane-based surfactants, such as TEGO Wet KL 245 and TEGO Wet 270, suffice to assist pigment wetting. With more difficult pigments and carbon blacks, TEGO Dispers 760 W is the right choice. It has good pigment wetting and stabilization. Critical pigments and high density pigments require an additive with particular stabilizing characteristics. TEGO Dispers 755 W exhibits its strength as a high molecular weight dispersing additive with outstanding, almost Newtonian, flow behavior, low viscosity and universal applicability for organic pigments and carbon blacks. Pigment dispersion Organic pigments Carbon blacks TEGO Dispers 685 TEGO Dispers 685 Solventborne TEGO Dispers 670 TEGO Dispers 710 TEGO Dispers 760 W TEGO Wet KL 245 TEGO Dispers 755 W TEGO Dispers 670 TEGO Dispers 710 TEGO Dispers 760 W TEGO Wet KL 245 TEGO Dispers 755 W TEGO Printing Inks Seite 29 Druckfarben_GB_2012_final.indd :05

30 Substrate wetting and flow Solventborne Substrate wetting and improving the print quality The cross-linking TEGO Rad additives have proved especially suitable in radiation-curing formulations. They not only enable substrate wetting characteristics to be adjusted but are also beneficial for drop formation. TEGO Rad 2200 N is a universal product, highly compatible in oligomers and monomers, which provides excellent wetting. TEGO Rad 2300 has shown itself as an even stronger surface wetting agent. TEGO Rad 2100 only makes minimal adjustments to wetting but ensures improved droplet lay-down. The TEGO Rad products are cross-linking in radiation-curing formulations as they contain acrylic groups. Although not cross-linking but nevertheless also very suitable for inkjet formulations is TEGO Glide 432 which ensures very good substrate wetting and a good lay-down for the ink. TEGO Rad 2200 N TEGO Rad 2300 TEGO Glide 432 TEGO Glide 410 TEGO Glide 100 TEGO Wet 270 TEGO Wet KL 245 TEGO Wet 500 TEGO Glide 100 In solventborne inkjet formulations, good wetting is provided by the solvent. Improvements can nevertheless be achieved by the use of suitable additives. TEGO Glide 410, which further increases wetting and improves flow, is recommended for this purpose. In the case of waterbornes, substrate wetting additives are nearly always required to lower surface tension and enable substrate wetting and flow to be adjusted. TEGO Wet KL 245, which is completely soluble in water, should be emphasized here. Other interesting products are TEGO Wet 500 and TEGO Glide 100, which can influence surface tension and the lay-down of the ink. Defoamers for manufacturing inkjet formulations and (for inks used) in circulation systems The search for defoamers for inkjet formulation is ongoing. There are often two reasons. Powerful homogenization equipment and grinding units are necessary for the manufacture and dispersion of inkjet formulations. The second reason is current machinery and heads in which the ink is pumped around a circulatory system. Both can lead to foam build-up. Seite 30 TEGO Printing Inks Druckfarben_GB_2012_final.indd :05

31 For waterborne and radiation-curing products, defoamers which are not too hydrophobic are useful. The viscosities are very low and the polarities also differ from those of classical gravure and flexographic inks. For radiation-curing inkjet formulations, TEGO Airex 920 is recommended as a silicone-free deaerator. It can be used in the dispersion stage or in the let-down. The highly compatible silicone-free TEGO Foamex 830 defoamer or the siloxane-based defoamer TEGO Foamex 810 is well suited for use in waterborne formulations. Both can be used at the dispersion and let-down stages. Another product for the let-down or subsequent incorporation is the siloxanebased TEGO Foamex 805. It shows its strength with excellent compatibility and good defoaming. Defoaming Millbase TEGO Airex 920 TEGO Foamex 830 TEGO Foamex 810 Let-down TEGO Foamex 843 TEGO Foamex 845 TEGO Foamex 1488 TEGO Foamex 805 TEGO Foamex 830 TEGO Foamex 810 TEGO Printing Inks Seite 31 Druckfarben_GB_2012_final.indd :05

32 Sales/Technical Support Hotline Africa Egypt Egyptian Promoters Center phone fax South Africa Evonik Degussa Africa (Pty.) Ltd. phone fax Americas Argentina Mayerhofer Argentina S.A. phone fax Brazil Evonik Degussa Brasil Ltda. phone fax Canada Evonik Goldschmidt Corp. phone fax Columbia INCOPACK S.A. phone fax Mexico Evonik Degussa México, S.A de C.V phone fax USA Evonik Goldschmidt Corp. phone fax Australia Australia (Sydney) International Sales & Marketing Pty. Ltd. phone fax New Zealand International Sales & Marketing (NZ) Ltd. phone fax Asia P.R. China Evonik Degussa Specialty Chemicals (Shanghai) Co., Ltd. Shanghai Branch phone fax Hong Kong Evonik Degussa Hong Kong Ltd. phone fax India Evonik Degussa India Pvt. Ltd. phone fax Indonesia PT Jebsen & Jessen Chemicals Indonesia phone fax Japan (Osaka) Evonik Degussa Japan Co., Ltd. phone fax Korea Evonik Degussa Korea Ltd. phone fax Malaysia Jebsen & Jessen Chemicals (M) Sdn Bhd phone fax Philippines Jebsen & Jessen Chemicals (P) Inc. phone fax Singapore Evonik (SEA) Pte. Ltd. phone fax Taiwan Evonik Degussa Taiwan Ltd. phone fax Thailand DKSH (Thailand) Ltd. phone fax Vietnam Viet Hoa Sinh Co., Ltd. phone fax Europe Austria Evonik Industries AG phone fax Belgium Evonik Industries AG phone fax Bulgaria HSH Chemie EOOD phone fax Czech Republic HSH Chemie s.r.o. phone fax France Evonik Industries AG phone fax Germany Evonik Industries AG phone fax Great Britain Evonik Industries AG phone fax Greece Goldchem EPE phone fax Hungary HSH - Chemie Kft. phone fax Italy Evonik Industries AG phone fax Netherlands Evonik Industries AG phone fax Poland Evonik Degussa Polska Sp.z.o.o. phone fax Portugal Horquim - Representações, Lda. phone fax Romania HSH Chemie SRL phone fax Russia OOO Evonik Chimia phone fax Scandinavia Evonik Industries AG phone fax Slovenia Parka d.o.o. phone fax Spain Evonik Industries AG phone fax Switzerland Evonik Industries AG phone fax Turkey Evonik Degussa Ticaret Ltd. Sti. phone fax For further information about listed and not listed countries please contact the International Sales/Technical Support Hotline or get your information at Evonik Industries AG Goldschmidtstraße Essen Germany phone fax This information and all further technical advice is based on our present knowledge and experience. However, it implies no liability or other legal responsibility on our part, including with regard to existing third party intellectual property rights, especially patent rights. In particular, no warranty, whether express or implied, or guarantee of product properties in the legal sense is intended or implied. We reserve the right to make any changes according to technological progress or further developments. The customer is not released from the obligation to conduct careful inspection and testing of incoming goods. Performance of the product described herein should be verified by testing, which should be carried out only by qualified experts in the sole responsibility of a customer. Reference to trade names used by other companies is neither a recommendation, nor does it imply that similar products could not be used. 05_2012 Druckfarben_GB_2012_final.indd :50