Wide Format Ink Types for Inkjet Printers
As wide format inkjet printers were designed for different types of printing requirements, chemists created different ink formulations to meet changing requirements of fade-resistance, outdoor durability, inexpensive materials for lower production costs, environmental concerns, and the ability to print directly on rigid sign boards. The six types of wide format ink are listed in the order in which they were introduced to the market.
- Tiny dye molecules are dissolved in the water of the ink and soak into the paper
- They produce brilliant, saturated colors; dye molecules don't scatter light
- Dye inks fade quickly in UV light, especially on microporous papers (UV-filtering laminating films or faming glass can prolong print life)
- Dye inks are not waterproof; prints can smear, run or smudge, even if they are dry, or when exposed to humidity or moisture
- Dye inks cost less, flow freely through inkjet nozzles,and are fine for everyday printing of documents, proofs, or photos that will be kept in a box or album
- Pigment inks use colorant particle, or pigments, that stay suspended in glycol. Residue from ink can clog printheads when exposed to air
- Pigment particles are distributed on the inkjet receptive coating, which controls dot gain
- Pigment inks are more fade-resistant and water-resistant than dye inks
- Uses pigments suspended in chemical solvents that can bond to less expensive, uncoated vinyl for outdoor graphics
- Solvents contain volatile organic compounds (VOCs) that pose workplace health and safety hazards
- Print shops must install special ventilation equipment and comply with strict environmental and health regulations
- Pigment particles are suspended in solvents made from extracts of refined mineral oil
- Solvents are less toxic but don't adhere as well to vinyl as true solvent inks
- When using eco-solvent inks, depending on the model, air scrubbers or specialized ventilation equipment is recommended
- Still considered hazardous chemicals
- Ink chemistry forms extremely resilient hard film (polymer) when exposed to controlled beam of UV light. The UV-light "cured"; prints are instantly dry.
- UV cure inks can print on many types of coated or uncoated rigid and flexible media
- Prints are outdoor durable without lamination or protective clearcoats
- UV-cure inks enable printers to run at higher speeds
- Uncured inks and UV-curing units may pose some risks to workers
- Inks don't release chemicals into the air because they don't dry through evaporation
- Uses water, a wetting agent, a humectant, and additives to carry latex polymer and pigment particles to the surface of the print media. The ink forms a latex polymer film when heated with an onboard radiant heater.
- Unlaminated prints on vinyl can last up to three years outdoors or in indoor window displays for up to 5 years (like eco-solvent inks)
- Can be used with lower-cost user-replaceable thermal inkjet printheads
- Latex inks are non-toxic, non-flammable, and non-combustible
- Wetting agent and humectant soften uncoated vinyl for improved ink adhesion
- Latex inks don't need special handling or hazard warning labels
Toners and Inks for Wide Format Electrophotographic Printers
Electophotographic printing devices use electrical processes to transfer images to paper.
- Toner is a mixture of ultra-fine powered chemicals that gain an electric charge when it comes in contact with a rotating drum. Tones include heat-sensitive plastic powders, iron oxide, pigments, and other ingredients.
- When the copier’s laser beam removes the charge from previously charged sections of the drum, certain areas of the drum are coated with toner
- When drum rolls over the paper, toner is transferred to the paper
- Toners include mix of heat-sensitive plastic powders, iron oxide, pigment, and other ingredients
HP Indigo Digital Press
- Electrically charged pigments are carried in a liquid ink that electrically controls the location of the printed particles
- ElectroInk is supplied in tubular cartridges of a concentrated paste that is diluted with oil to form a fluid mixture of carrier liquid and colorant particles
- Photos printed with ElectroInk can resist fading and color shifts for longer than standard silver-halide photo papers used in darkroom processing