Printing process
View Patent ↗There is described a recording medium and related ink jet printing method which comprises the steps of: 1) printing onto a receiving medium which comprises a substrate coated with at least one ink receiving layer comprising polymeric particles having film forming temperatures between 60° to 140 ° C. and a binder, and 2) heating the printed image to form a stable image-protecting coating. Preferably the printed image is heated by passing through a laminator. Alternatively the printed image is heated by passing through a laminator in conjunction with a second, inert releasing sheet which is held against the top surface of the print material. The second sheet may be used to produce a particular appearance to the final image such as high gloss or a security pattern. The receiving layers of the invention provide bright images after printing and fusing which show a high level of scratch and rub resistance even when wet.
1. An ink jet printing method comprising the steps of:
a. printing on to a receiving medium which comprises a substrate coated with a single ink receiving layer comprising polymeric particles having film forming temperatures between 60 to 140° C. and a binder; and
b. heating the printed image to form a stable image-protecting coating.
2. A method according to claim 1 , wherein said ink receiving layer is coated as an aqueous formulation on top of said substrate.
3. A method according to claim 1 , wherein the printed image is heated under pressure to form the protective coating.
4. A method according to claim 1 , wherein the printed image is heated by passing through a laminator.
5. A method according to claim 4 , wherein an inert sheet is in contact with said ink receiving layer and passed through said laminator.
6. A method according to claim 5 , wherein said inert sheet is selected from the group consisting of release papers, release liners, silicone release liners, casting films, casting papers and polyester films.
7. A method according to claim 5 , wherein said inert sheet is used to impart a high gloss, embossed pattern or security symbol to the final image.
8. A method according to claim 1 , wherein said binder is a hydrophilic binder.
9. A method according to claim 8 , wherein said hydrophilic binder is polyvinyl alcohol.
10. A method according to claim 1 , wherein said particulate polymer comprises low density polyethylene.
11. A method according to claim 10 , wherein said particulate polymer comprises low density polyethylene particles having an average particle size of approximately 25 μm.
12. A method according to claim 1 , wherein the inks used to print the image on said receiving layer are selected from the groups consisting of aqueous inks, mineral oil inks and inks based on organic solvents.