Highly Pigmented Colorants for UV/EB

Transcription

1 Highly Pigmented Colorants for UV/EB Guidelines For Use 262 Carlton Drive Carol Stream, IL Tel:

2 Highly Pigmented Colorants for Radiation Cured Printing Applications Introducing Yellow 14 Lithol Rubine 57:1 Phthalo Blue 15:4 Black 7 White DPP Red Warm Red 48:1 Green 7 Reflex Blue Violet 23 Yellow 74 Quinacridone Red 122 Yellow 139 Red Carlton Drive Carol Stream, IL Toll Free:

3 Introduction As part of our commitment to bring value solutions to the market, Central Chemical & Service would like to present our new range of easily dispersible products designed to bring value in use in the manufacture of UV/EB curable printing inks. In this technical bulletin we are introducing a range of fourteen pigment colorants for use in radical curable printing applications. The following information and formulas can also be used as a guideline for ink formulations when using other colorants in our product line. The colorants have been specifically formulated to ensure that they offer the ink maker maximum formulation flexibility and ease of processing. The specific selection of the polyester acrylate oligomer backbone allows for letdown variations into flexo, offset and screen formulations. We will also custom formulate or consult on let down packages designed for use with RadFlex colorants for specific print applications in Flexo and Screen printing. Key Benefits Product Overview high pigmentation stir in dispersibility ease of handling high mileage and high gloss multipurpose formulated for use in flexo, offset and screen excellent storage stability Colorant Chromophore Viscosity Pa.s* Dispersion m Pigmentations % Yellow 14 PY < Lithol Rubine PR 57:1 31 < Phthalo Blue PB 15:4 33 < Violet PV < Black PB 7 37 < White PW 6 38 < * low shear viscosity measurement at 10s 1.

4 Guidelines for Use / Start Point Formulations Flexographic Inks The following formulations were used to let down RadFlex colorants for use in flexographic printing. Central Chemical will also custom blend or consult on let down packages designed for use with RadFlex colorants for specific print applications or substrates. Yellow Magenta Cyan Violet Black White Colorant Letdown Polyester Oligomer GPTA TMPEOTA IRGASTAB UV Photoinitiator Blend GPTA propylated glycerol triacrylate TMPEOTA ethoxylated trimethylpropane triacrylate Photoinitiator Blends % Colours Black White DAROCUR EDB DAROCUR ITX IRGACURE 651 IRGACURE 379 IRGACURE 907 IRGACURE Final Ink Formulations Pigmentation Polyester Acrylate GPTA TMPEOTA IRGASTAB UV10 Photoinitiator Blend Yellow Magenta Cyan Violet Black White Procedure A letdown formulation is prepared by dissolving the appropriate weights of photoinitiators and stabilizer in the GPTA monomer. Heat is used to aid dissolution, and on completion the letdown is cooled to room temperature. The colorant is added to a pot along with the additional oligomer and letdown solution. A butterfly impeller is then used to mix the components until a homogeneous final ink was obtained ( approximately 5 minutes at a tip speed of ~ 3.5 m/s ).

5 Guidelines for Use / Start Point Formulations Flexographic Ink Results Colorant Yellow Pigm n ( % ) Viscosity ( Pa.s ) ( g/m 2 ) Gloss ( 60 o ) Stability ( weeks ) > 4 Magenta > 4 Cyan > 4 Violet > 4 Black > 4 White > 4 Methods of Assessment Viscosity Cone & Plate Controlled Stress Rheometer Viscosity measured at shear rate of 10s 1 Density Prufbau print, metal cone, 500N, ms 1, 25 o C Printed on Top Coated White Polyethylene substrate at g/m 2 Gloss Mini Glossmaster / 60 o Stability Inks are filled to the brim in polypropylene containers and placed in an oven calibrated at 60 o C. Inks are assessed on a weekly basis, for a maximum of 4 weeks, for premature curing.

6 Offset Inks Starting Point Formulations Porous Substrates The following formulations were used to let down RadFlex colorants for use in offset lithography. Black Cyan Magenta Yellow Colorant Ebecryl Ebecryl Inert filler TRPGDA ViaCure DX Starting Point Formulations Non Porous Substrates Black Cyan Magenta Yellow Colorant ViaSet Inert filler TRPGDA ViaCure DX The above recommendations were formulated and tested by Cytec Surface Specialties for tack, gloss, viscosity and density to meet the requirements for offset lithography. Colorant % (pigment solids) Black (40) Cyan (35) Magenta (30) Yellow (30)

7 Guidelines for Use / Start Point Formulations Offset Inks The following formulations were used to let down RadFlex colorants for use in offset lithography. Yellow Magenta Cyan Violet Black White Colorant Letdown Polyester Oligomer GPTA IRGASTAB UV Photoinitiator Blend GPTA propylated glycerol triacrylate Photoinitiator Blends % Colours Black White DAROCUR EDB DAROCUR ITX IRGACURE 651 IRGACURE 379 IRGACURE 907 IRGACURE Final Ink Formulations Pigmentation Polyester Acrylate GPTA IRGASTAB UV10 Photoinitiator Blend Yellow Magenta Cyan Violet Black White Procedure A letdown formulation is prepared by dissolving the appropriate weights of photoinitiators and stabilizer in the GPTA monomer. Heat is used to aid dissolution, and on completion the letdown is cooled to room temperature. The colorant is added to a pot along with the additional oligomer and letdown solution. A butterfly impeller is then used to mix the components until a homogeneous final ink was obtained (approximately 5 minutes at a tip speed of ~ 3.5 m/s ).

8 Guidelines for Use / Start Point Formulations Offset Ink Results Colorant Yellow Pigm n ( % ) Viscosity ( Pa.s ) Tack ( g/m 2 ) Gloss ( 60 o ) Stability ( weeks ) > 4 Magenta > 4 Cyan > 4 Violet > 4 Black > 4 White > 4 Offset prints are illustrated at the end of this document Methods of Assessment Viscosity Cone & Plate Controlled Stress Rheometer Viscosity measured at shear rate of 10s 1 Tack Beta Tech Tack Meter Gloss Mini Glossmaster / 60 o Density Prufbau print, metal cone, 1200N, 0.5ms 1, 25 o C Printed on APCO II/II substrate at g/m 2 Stability Inks are filled to the brim in polypropylene containers and placed in an oven calibrated at 60 o C. Inks are assessed on a weekly basis, for a maximum of 4 weeks, for premature curing.

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