Coating and production method thereof by inkjet printing methods

Abstract

There are several coatings and a method for surface finishing, in particular for producing durable and stable surface coatings using ink jet printing methods. The coating comprises a first layer, which can be produced from one or more ink jet-capable inks, and a second layer, which can be produced from one or more top coats, wherein at least the first layer is applied using an ink jet print head.

Claims

1. A method for the application of a coating to a surface, or to a substrate, said coating comprising a primer, a first coat, which comprises one or more inks, and a second coat, which comprises one or more covering layers, wherein at least one ink is a UV curing ink and at least one covering layer is a UV curing lacquer; said method comprising in order the steps of (a) applying a primer, (b) printing at least one UV curing ink by means of an inkjet printer on said primer, (c) commencing gelling of the ink by irradiation with light exhibiting wavelengths of from 250 to 450 nm, (d) applying at least one covering layer by means of an inkjet printer, and (e) completely curing said coating over its entire structure with UV light; wherein said primer contains a binding component and a curing component in a mixing ratio of from 1:0.7 to 1:1.2, and wherein the mixing ratio is OH groups: NCO groups or epoxy groups: NH groups; and wherein said primer comprises a binding component containing from 10 to 70% by weight of polyalcohols or epoxy resins, from 5% to 10% by weight of flatting agent, from 0 to 5% by weight of waxes, from 0.1% to 2% by weight of accelerators, from 0.2% to 1% by weight of dispersing agent, from 0.1% to 2% by weight of wetting agent, from 0.1 to 2% by weight of silicones, from 0 to 60% by weight of pigments, and from 0 to 60% by weight of fillers based on the total weight of said binding component.

2. The method according to claim 1, wherein the primer is applied by spray coating.

3. The method as defined in claim 1, wherein the inks and/or covering layers are printed by means of an inkjet printing head capable of moving in three vertically superposed planes.

4. The method according to claim 1, wherein items of plastics materials are coated, in which the plastics materials are selected from the group consisting of plastics materials produced from vinyl chloride, acrylic-butadiene-styrene copolymer, acrylic-butadiene-styrene copolymer/polycarbonate, polycarbonate, acrylonitrile-styrene-acrylate, filler-free and filled polypropylene, filler-free and filled polyamide, poly(oxymethylene), poly(butylene terephthalate), thermoplastic polyester elastomers and ethylene-propylene-diene rubber.

5. The method according to claim 1, wherein PVC profiles are coated.

6. The method according to claim 1, wherein at least one ink comprises pigments, oligomers, and/or reactive diluents.

7. The method according to claim 1, wherein at least one ink contains from 0 to 15% of pigment, from 5 to 50% of oligomer, and from 20 to 80% of monofunctional, difunctional and/or trifunctional reactive diluent based on the weight of the ink.

8. The method according to claim 1, wherein said binding component of said primer contains polyalcohols and said curing component of said primer contains isocyanates.

9. The method according to claim 1, wherein said binding component of said primer contains epoxy resins and said curing component of said primer contains NH-functional substances.

10. The method according to claim 1, wherein the UV curing lacquer contains from 5 to 50% of oligomer and from 20 to 80% of monofunctional, difunctional and/or trifunctional reactive diluent based on the weight of the covering layer.

11. The method according to claim 1, wherein the covering layer wets the first coat only partially.

12. The method according to claim 1, wherein said inks in the cured state have a surface energy in the range of from 20 to 50 mN/m.

13. The method according to claim 1, wherein said inks have a surface tension of less than 35 mN/m.

14. A method for the application of a coating to a surface, or to a substrate, said coating comprising a primer, a first coat, which comprises one or more inks, and a second coat, which comprises one or more covering layers, wherein at least one ink is a UV curing ink and at least one covering layer is a UV curing lacquer; said method comprising in order the steps of (a) applying a primer, (b) printing at least one UV curing ink by means of an inkjet printer on said primer, (c) commencing gelling of the ink by irradiation with light exhibiting wavelengths of from 250 to 450 nm, (d) applying at least one covering layer by means of an inkjet printer, and (e) completely curing said coating over its entire structure with UV light; wherein said inks in the cured state have a surface energy in the range of from 20 to 50 mN/m; and wherein said primer comprises a binding component containing from 10 to 70% by weight of polyalcohols or epoxy resins, from 5% to 10% by weight of flatting agent, from 0 to 5% by weight of waxes, from 0.1% to 2% by weight of accelerators, from 0.2% to 1% by weight of dispersing agent, from 0.1% to 2% by weight of wetting agent, from 0.1 to 2% by weight of silicones, from 0 to 60% by weight of pigments, and from 0 to 60% by weight of fillers based on the total weight of said binding component.

15. The method according to claim 14, wherein the surface energy is in the range of from 25 to 40 mN/m.

16. The method according to claim 14, wherein the surface energy is in the range of from 26 to 35 mN/m.

17. A method for the application of a coating to a surface, or to a substrate, said coating comprising a primer, a first coat, which comprises one or more inks, and a second coat, which comprises one or more covering layers, wherein at least one ink is a UV curing ink and at least one covering layer is a UV curing lacquer; said method comprising in order the steps of (a) applying a primer, (b) printing at least one UV curing ink by means of an inkjet printer on said primer, (c) commencing gelling of the ink by irradiation with light exhibiting wavelengths of from 250 to 450 nm, (d) applying at least one covering layer by means of an inkjet printer, and (e) completely curing said coating over its entire structure with UV light; wherein said inks have a surface tension of less than 35 mN/m; and wherein said primer comprises a binding component containing from 10 to 70% by weight of polyalcohols or epoxy resins, from 5% to 10% by weight of flatting agent, from 0 to 5% by weight of waxes, from 0.1% to 2% by weight of accelerators, from 0.2% to 1% by weight of dispersing agent, from 0.1% to 2% by weight of wetting agent, from 0.1 to 2% by weight of silicones, from 0 to 60% by weight of pigments, and from 0 to 60% by weight of fillers based on the total weight of said binding component.

18. The method according to claim 17, wherein said surface tension is less than 30 mN/m.

19. The method according to claim 17, wherein said surface tension is less than 26 mN/m.

20. A method for the application of a coating to a surface, or to a substrate, said coating comprising a primer, a first coat, which comprises one or more inks, and a second coat, which comprises one or more covering layers, wherein at least one ink is a UV curing ink and at least one covering layer is a UV curing lacquer; said method comprising in order the steps of (a) applying a primer, (b) printing at least one UV curing ink by means of an inkjet printer on said primer, (c) commencing gelling of the ink by irradiation with light exhibiting wavelengths of from 250 to 450 nm, (d) applying at least one covering layer by means of an inkjet printer, and (e) completely curing said coating over its entire structure with UV light; wherein said primer contains a binding component and a curing component in a mixing ratio of from 1:0.7 to 1:1.2, and wherein the mixing ratio is OH groups: NCO groups; and wherein said primer comprises a binding component (constituents based on the total weight of the binding component) containing: TABLE-US-00008 acrylate-polyol 22% by weight, flatting agent 5% by weight, accelerator 0.2% by weight, wetting agent 0.5% by weight, dispersing agent 0.2% by weight, antifoaming agent 0.2% by weight, butyl acetate 61.9% by weight, and solvent naphtha 10% by weight.

21. A method for the application of a coating to a surface, or to a substrate, said coating comprising a primer, a first coat, which comprises one or more inks, and a second coat, which comprises one or more covering layers, wherein at least one ink is a UV curing ink and at least one covering layer is a UV curing lacquer; said method comprising in order the steps of (a) applying a primer, (b) printing at least one UV curing ink by means of an inkjet printer on said primer, (c) commencing gelling of the ink by irradiation with light exhibiting wavelengths of from 250 to 450 nm, (d) applying at least one covering layer coat by means of an inkjet printer, and (e) completely curing said coating over its entire structure with UV light; wherein said inks in the cured state have a surface energy in the range of from 20 to 50 mN/m; and wherein said primer comprises a binding component (constituents based on a total weight of the binding component) containing: TABLE-US-00009 acrylate-polyol 22% by weight, flatting agent 5% by weight, accelerator 0.2% by weight, wetting agent 0.5% by weight, dispersing agent 0.2% by weight, antifoaming agent 0.2% by weight, butyl acetate 61.9% by weight, and solvent naphtha 10% by weight.

22. A method for the application of a coating to a surface, or to a substrate, said coating comprising a primer, a first coat, which comprises one or more inks, and a second coat, which comprises one or more covering layers, wherein at least one ink is a UV curing ink and at least one covering layer is a UV curing lacquer; said method comprising in order the steps of (a) applying a primer, (b) printing at least one UV curing ink by means of an inkjet printer on said primer, (c) commencing gelling of the ink by irradiation with light exhibiting wavelengths of from 250 to 450 nm, (d) applying at least one covering layer by means of an inkjet printer, and (e) completely curing said coating over its entire structure with UV light; wherein said inks have a surface tension of less than 35 mN/m; and wherein said primer comprises a binding component (constituents based on a total weight of the binding component) containing: TABLE-US-00010 acrylate-polyol 22% by weight, flatting agent 5% by weight, accelerator 0.2% by weight, wetting agent 0.5% by weight, dispersing agent 0.2% by weight, antifoaming agent 0.2% by weight, butyl acetate 61.9% by weight, and solvent naphtha 10% by weight.

Description

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Example 1: 3-Layer Architecture

(1) Primer

(2) Binding component (constituents based on the total weight of the binding component):

(3) TABLE-US-00001 acrylate-polyol 22% flatting agent .sup.5% accelerator 0.2% wetting agent 0.5% dispersing agent 0.2% antifoaming agent 0.2% butyl acetate 61.9% solvent naphtha 10%

(4) Curing Component:

(5) conventional commercial isocyanate curing agent in a mixing ratio of 1:1

(6) Ink

(7) (percentages based on the total weight of the ink:)

(8) TABLE-US-00002 pigment 0 to 15% oligomer 5 to 50% reactive diluent 20 to 80% further additives 0 to 5%

(9) Covering Layer

(10) binding component (percentages based on the total weight of the binding component):

(11) TABLE-US-00003 acrylate-polyol 25% accelerator 1% wetting agent 0.5%.sup. flatting agent 1% light screen 1% solvent naphtha 20% butyl acetate 51.5%

(12) Curing Component:

(13) conventional commercial isocyanate curing agent in a mixing ratio of 1:1

(14) Substrate

(15) Glass, cleaned with isopropyl alcohol

(16) The primer was applied by spraying. The primer coat was dried at room temperature for 24 hours. The ink was subsequently printed onto the substrate by means of an ORXY printer marketed by Swissqprint. The covering layer was applied by means of spray coating. The printed structure was checked 7 days later with the following results (see Table 1):

(17) TABLE-US-00004 TABLE 1 Nominal Test value Result Cross-cut 1 OK DIN EN ISO 2409 Condensation water constant degree of OK climate blistering = 0 DIN EN ISO 6270-2 CH, 1 OK 240 h, 40 C.>95% rel. humidity then cross-cut (see above) ATLAS Suntest delta E < 5 OK 240 h with quartz filter Drip test, cleaner's naphtha 5 OK DIN EN ISO 105-A02 Care resistance test trace 1, OK DIN EN ISO 105-X12, 9N, felt 1 stroke: 50 mm, 30 DH; felt: 1 cm.sup.2 glass cleaner Wipe test with Crockmeter trace = 0, OK DIN EN ISO 105-X12, 9N, felt = 0 stroke: 50 mm, felt: 1 cm.sup.2 Heat storage 240 h, 90 C.: optical change 0 OK DIN EN ISO 4628-1 haptical change 0 OK DIN EN ISO 4628-1 cross-cut 1 OK DIN EN ISO 2409 scratch resistance, Erichsen rod 318 no DIN EN ISO 1518, 10N, = 75 mm tearing

Example 2: 2-Layer Architecture

(18) Ink:

(19) TABLE-US-00005 Amount Constituent [% by weight] Pigment 0 to 15 Oligomer 5 to 50 Reactive diluent 20 to 80 (monofunctional, difunctional or trifunctional) Further additives 0 to 5

(20) Covering Layer:

(21) TABLE-US-00006 Amount Constituent [% by weight] Oligomer 5 to 50 Reactive diluent 20 to 80 (monofunctional, difunctional or trifunctional) Further additives 0 to 5

(22) Substrate

(23) PVC, cleaned with isopropyl alcohol (IPA)

(24) The ink is printed onto the substrate by means of a conventional commercial printer such as, for example, Swissqprint ORXY or Durst RHO. Subsequently a covering layer is applied with a printing head as marketed by, for example, Konica Minolta or Fujifilm Dimatix, or likewise with a conventional commercial printer. Alternatively, the covering layer can be applied by spraying.

(25) The object was tested 7 days later, giving the following results (see Table 2):

(26) TABLE-US-00007 TABLE 2 Nominal Test value Result Cross-cut 1 OK DIN EN ISO 2409 Condensation water constant degree of OK blistering = 0 climate DIN EN ISO 6270-2 CH, 1 OK 240 h, 40 C.>95% rel. humidity then cross-cut (see above) ATLAS Suntest delta E < 5 OK 240 h with quartz filter Drip test, cleaner's naphtha 5 OK DIN EN ISO 105-A02 Care resistance test trace 1 OK DIN EN ISO 105-X12, 9N, felt 1 stroke: 50 mm, 30 DH; felt: 1 cm.sup.2 glass cleaner Wipe test with Crockmeter trace = 0, OK DIN EN ISO 105-X12, 9N, felt = 0 stroke: 50 mm, felt: 1 cm.sup.2 Heat storage 240 h, 90 C.: optical change 0 OK DIN EN ISO 4628-1 haptical change 0 OK DIN EN ISO 4628-1 cross-cut 1 OK DIN EN ISO 2409 scratch resistance, Erichsen rod 318 no tearing DIN EN ISO 1518, 10N, = 75 mm