hp indigo digital printing hp ElectroInk Frequently Asked Questions what is hp ElectroInk® ? do images printed with hp ElectroInk have any degradation of color values? hp ElectroInk is a unique liquid ink that combines the advantages of electronic printing with the qualities of liquid Images printed with hp ElectroInk were analyzed after a ink. hp ElectroInk contains charged pigmented particles in print run of 100,000 impressions, and measured for a a liquid carrier, and enables digital printing by electrically change in color. The analysis found no degradation in color controlling the location of these particles. values of the xth print compared to the 1st print (∆E*< 2)2. how does hp ElectroInk support the performance does hp ElectroInk that has been stored for a period required for high quality, digital color printing? of time have any degradation of color values? The small particle size in the liquid carrier enables high The hp ElectroInk was analyzed after one year of storage resolution, uniform gloss, sharp image edges, and very and measured for a change in color. The analysis found no thin image layers which closely follow the surface degradation in color values (∆E*< 3). topography of the paper resulting in a highly uniform finish. what is hp ElectroInk’s ability to withstand exposure to light? what is hp ElectroInk’s resistance to abrasion? hp ElectroInk’s ability to withstand exposure to light is hp ElectroInk’s resistance to abrasion is characterized by measured by utilizing a test for Light-Fastness. utilizing a test procedure for rub-resistance that measures The lightfastness test measures the print’s resistance to the ink’s adhesion to the substrate. ultraviolet light by measuring the change that occurred between the exposed area to the unexposed area. HP Indigo labs utilize two types of measurements that Two separate tests of lightfastness are shown below. characterize rub resistance: The first shows results based on a blue wool reference 1. Sutherland abrasion resistance - A standard scale, while the second shows results based on percentage measurement that provides guidelines of fading (optical density) and deltaE* (color coordinate 2. GaCat abrasion resistance - A standard measurement changes). that provides guidelines and a semi-quantitative scale. lightfastness test 1: Blue Wool sutherland measurement results: The light fastness test was done using a Xenon UV Lamp No significant difference in abrasion resistance of 100% according to the British Standard BS 1006B02 for indoor solids vs. close to 100% halftone gray images was found. conditions and ISO1134M1 method for outdoor conditions gacat measurement1 results: The result is on a 1-8 blue wool reference scale. hp ElectroInk performs better than grade 3 1Completely faded 0 No damage 8 No fading 10 Completely damaged 2 DeltaE* expresses the color change between the X print to the 1st. print at the same Optical density. The optimal result is when DeltaE* is close to zero. 1 The conditions of measurements were as follows: 100% solids test image,receptor C5, frequency 2 sec-1, 120 sec. please note that specific papers/substrates may give deviations from the presented test results. indoor test ISO1006B02 hp ElectroInk 3.1 Offset Ink Cyan Yellow Magenta Black Cyan Yellow Magenta Black Paper (untreated) 5-7 4-5 5 5 6-7 2-3 1 4 PVC (treated) 6-7 4-6 5-7 4-5 PET (treated) 6-7 1-2 5-7 3-4 outdoor test ISO11341M1 PVC (treated) 6-7 4-6 5-6 3-6 PET (treated) 6-7 1-2 3-4 3-4 indoor test ISO105B02 hp ElectroInk 3.2 Offset Ink Cyan Yellow Magenta Black Cyan Yellow Magenta Black Paper (untreated) 76 6 3-46-72-31 4 Blue Wool Scale [BWS] scale Days indoors comments 13.75Very poor 1 2 26 poor 319fair 465moderate 5130 good 3 4 6260 Very good 7520excellent 8 1100 outstanding 5 6 The blue wool scale is composed of 8 strips of wool fabric, of different standard dyeing. Their chromatic grade goes from the Standard 1, with very scarce light fastness, to the Standard 8 with very elevated light fastness. Every standard is twice more solid than the preceding one. 7 8 example of a blue wool scale lightfastness test 2: Optical density & Color Coordinates Paper type Simulated by testing on This lightfastness test was done by exposing test samples for 3-day cycles while monitoring changes in optical SBR coated Gloss Condat Gloss density (%fading) and color coordinates (deltaE*). SBR coated Matte Condat Matte Each 3-day cycle simulates 6 years exposure under the above conditions. Three cycles of six days each, simulates Acrylic coated BVS eighteen years. The tests were done using ElectroInks and Uncoated Carnival Offset inks on various types of paper, intended to simulate a variety of typical substrates. deltaE %fading 10.00 20.00 30.00 40.00 60.00 50.00 15.00 35.00 45.00 25.00 55.00 0.00 5.00 -10 10 15 20 30 40 60 50 35 45 25 65 55 -5 lightfastness test2: equivalent) (6years exposure change at3days incolorcoordinates 0 5 lightfastness test 2: change in Optical Density at 3 days exposure (6 years equivalent) (6years lightfastness test2: change exposure inOptical Density at3days SBR Gloss SBR Gloss YM C YM C SBR Matte SBR Matte Acrylic Acrylic coated coated Uncoated Uncoated SBR Gloss SBR Gloss SBR Matte SBR Matte Acrylic Acrylic coated coated paper types Uncoated paper types Uncoated SBR Gloss SBR Gloss SBR Matte SBR Matte Acrylic Acrylic coated coated Uncoated Uncoated SBR Gloss SBR Gloss SBR Matte SBR Matte K K Acrylic Acrylic E1 offset coated coated E1 offset Uncoated Uncoated how resistant to heat are substrates printed with hp ElectroInks? The test for heat resistance measures the changes in color coordinates and optical density of a printed material which is exposed to heat. Heat resistance was tested by exposing various printed substrates at a temperature of 120° for 30 minutes. heat resistance test: change in optical density 6.5 6 5.5 5 4.5 4 3.5 3 % fading 2.5 2 offset 1.5 EI3.1 1 EI3.2 -0.5 0 SBR coated SBR coated Acrylic coated Uncoated Gloss Matte paper type heat resistance test: change in color coordinates 3.6 3.3 3.0 2.7 2.4 2.1 1.8 Delta E* 1.5 1.2 offset 0.9 EI3.1 0.6 EI3.2 0.3 0 SBR coated SBR coated Acrylic coated Uncoated Gloss Matte paper type may hp ElectroInk be used for printing food may hp ElectroInk be used for printing food packaging applications in the United States? packaging applications in the European Union? Certain hp ElectroInk products, which are listed in the table Certain hp ElectroInk products, which are listed in the table below, are compliant with FDA requirements for printing on below, are compliant with requirements for printing on the the non-food contact side of food packaging of an non-food contact side of food packaging of an appropriate appropriate multiplayer food packaging material. multiplayer food packaging material under the German The material used for the food packaging in conjunction and European food legislation (German Bundesinstitut fur with the approved hp ElectroInk must be comprised of one gesundheitlichen Verbraucherschutz und Veterinarmedizin of the following materials: (1) low density polyethylene (BgVV) and European Union (EU). The material used for the (LDPE) that is at least 40 microns thick; (2) polypropylene food packaging in conjunction with the approved that is at least 20 microns thick; (3) polyester which is at hp ElectroInk must be Series 1 inks least 12 microns thick. The resulting packages may be comprised of one of the used to hold all types of food at temperatures up to 100 following materials: Mark 3.1 Cyan deg C (also known as US FDA's Condition of Use B, (1) low density polyethylene Mark 3.1 Magenta "Boiling Water Sterilized", under 21 CFR 176.170). (LDPE) that is at least 40 microns thick; Mark 3.1 Yellow Series 1 inks (2) polypropylene that Series 2 inks Mark 3.1 Black is at least 20 microns thick; Mark 3.1 Cyan Mark 3.2 Cyan (3) polyester which is at least Orange 003 Mark 3.1 Magenta 12 microns thick. Mark 3.2 Magenta Green 011 The resulting packages may Mark 3.1 Yellow Mark 3.2 Yellow be used to hold all types of Blue 013 Mark 3.1 Black food at temperatures up to Mark 3.2 Black Violet 065 100 deg C. Orange 003 Orange 070 We are investigating the Red 006 Green 011 status of series 2 inks and Green 072 Transparent 025 expect to have the data Blue 013 Violet 071 available by spring 2003. Violet 065 are any additional products recommended to Red 006 enhance the adhesion of hp ElectroInk to the plastic Transparent 025 substrates typically used in food packaging? White We recommend the use of a product called Topaz, which is distributed by HP Indigo, and is utilized in coating plastic substrates to enhance their compatibility with hp ElectroInk ink. can substrates treated with Topaz be used for printing on food-packaging applications? In the U.S., substrates treated with Topaz can be used for printing on the non-food-contact-side of food packaging when they are composed of any of the following materials: (1) low-density polyethylene (LDPE) that is at least 40 microns thick; (2) polypropylene that is at least 20 microns thick; or (3) polyester which is at least 12 microns thick. The alcohol solvent evaporates after application, leaving the Topaz as a dry layer.