Ink composition for liquid jet printing

Abstract

Non-aqueous ink composition for liquid ink jet printing including: a vehicle comprising one or more organic solvent(s) liquid at ambient temperature, or one or more organic compound(s) solid at ambient temperature and liquid at the projection temperature; one or more dye(s) and/or pigment(s); a binder, comprising at least one binding resin consisting of a copolymer of vinylidene chloride and of at least one other monomer, in solution at ambient temperature in the organic solvent(s) or in solution at the projection temperature in the organic compound(s). A method for marking substrates, supports or objects includes projection onto the substrates, supports or objects of the ink composition by a liquid ink jet printing technique. A substrate, support or object, particularly flexible substrate, is provided with a marking obtained by drying and/or absorption of the composition.

Claims

1. Non-aqueous ink composition for liquid ink jet printing comprising: a vehicle comprising one or more organic solvent(s), liquid at ambient temperature, wherein the vehicle comprises a majority proportion by weight of the total weight of the vehicle of one or more ketones; one or more dye(s) and/or pigment(s) present in an amount from 0.05% to 25% by weight of dye(s) and/or pigment(s) with respect to the total weight of the ink composition; a binder, comprising at least one binding resin consisting of a copolymer of vinylidene chloride and of at least one other monomer, in solution at ambient temperature in the organic solvent(s).

2. Ink composition according to claim 1, in which said at least one other monomer is a monomer comprising a single ethylenically unsaturated carbon-carbon double bond.

3. Ink composition according to claim 2, in which said at least one monomer comprising a single ethylenically unsaturated carbon-carbon double bond is selected from vinyl chloride, alkyl acrylates and alkyl methacrylates, acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, maleic acid, itaconic acid, and mixtures thereof.

4. Ink composition according to claim 1, in which the binder represents 0.1 to 30% by weight of the total weight of the ink composition.

5. Ink composition according claim 1, in which the binder comprises at least 10% by weight of said at least one binding resin consisting of a copolymer of vinylidene chloride and of at least one other monomer.

6. Ink composition according to claim 1, in which apart from the at least one binding resin consisting of a copolymer of vinylidene chloride, the binder further comprises one or more other binding resin(s).

7. Ink composition according to claim 1, in which the vehicle represents at least 20% by weight of the total weight of the ink composition.

8. Ink composition according to claim 1, in which the at least one ketone is selected from aliphatic ketones of 3 to 10 carbon atoms; cyclic ketones; and mixtures thereof.

9. Ink composition according to claim 1, in which the vehicle comprises a majority amount by weight of the total weight of the vehicle of methyl ethyl ketone.

10. Ink composition according to claim 1, in which one or more organic solvent(s) other than ketones is (are) added in the vehicle in a minority proportion by weight, with respect to the total weight of the vehicle.

11. Ink composition according claim 1, in which said dye(s) and/or pigment(s) is (are) selected from dyes and pigments known under the denomination “C.I. Solvent Dyes” and “C.I. Pigments”.

12. Ink composition according to claim 11, in which said “Solvent Dyes” are selected from C.I. Solvent Black 3, 7, 27, 28, 29, 35, 48, 49, C.I. Solvent Blue 38, 44, 45, 70, 79, 98, 100, 129, C.I. Solvent Red 8, 49, 68, 89, 124, 160, 164, C.I. Solvent Yellow 83:1, 126, 146, 162, C.I. Solvent Green 5, C.I. Solvent Orange 97, C.I. Solvent Brown 20, 52, and C.I. Solvent Violet 9.

13. Ink composition according to claim 11, in which said “C.I. Pigments” are selected from dispersions of Pigment Blue 15:1, 15:3, 60, of Pigment Green 7, of Pigment Black 7, of Pigment Red 48:2, 144, 149, 166, 185, 202, 208, 214, 254, of Pigment Violet 19, 23, of Pigment Yellow 17, 83, 93, 139, 151, 155, 180, 191, of Pigment Brown 23, 25, 41, or of Pigment White 6.

14. Ink composition according to claim 1, further comprising one or more plastifier(s) in an amount of at least 0.05% by weight of the total weight of the ink composition.

15. Ink composition according to claim 1, further comprising at least one conductivity salt in an amount of 0.1 to 20% by weight of the total weight of the ink composition.

16. Ink composition according to claim 15, in which said conductivity salt is selected from salts of alkaline metals, salts of alkaline earth metals, and simple or quaternary ammonium salts; said conductivity salts being in the form of halogenides, perchlorates, nitrates, thiocyanates, formiates, acetates, sulphates, propionates, trifluoroacetates, triflates(trifluoromethane sulphonates), hexafluorophosphates, hexafluoroantimonates, tetrafluoroborates, picrates, carboxylates and sulphonates.

17. Ink composition according to claim 1, which has a conductivity in the liquid state greater than or equal to 5 μS/cm at 20° C.

18. Ink composition according to claim 1, further comprising one or more additive(s) selected from anti-foaming agents; chemical stabilisers; UV stabilisers; surface active agents; agents inhibiting corrosion by salts; bactericides, fungicides and biocides; and pH regulating buffers.

19. Method for marking a substrate, support, or object by projection onto said substrate, support or object of an ink by a liquid ink jet printing technique, characterised in that the projected ink is an ink composition according to claim 1.

20. Substrate, support or object characterised in that it is provided with a marking obtained by drying and/or absorption of the ink composition according to claim 1.

21. Substrate, support or object according to claim 20, characterised in that the substrate is made of metal, of glass; of ceramic; of a material containing cellulose; of an organic polymer; of polymethylmethacrylate PMMA (“Plexiglas”); of fabric; of natural or synthetic rubber; or made of any other non-porous or porous substance; or made of a composite of several of the preceding materials.

22. Substrate according to claim 21, the substrate being flexible.

23. Ink composition according to claim 8, in which the aliphatic ketones of 3 to 10 carbon atoms are selected from acetone, butanone (methyl ethyl ketone), 2-pentanone (methyl propyl ketone), 3-methyl-2-butanone (methyl isopropyl ketone), 4-methyl-2-pentanone (methyl isobutyl ketone) and mixtures thereof.

24. Ink composition according to claim 8, in which the cyclic ketone is cyclohexanone.

25. Ink composition according to claim 1, in which the vehicle consists of one or more ketone(s).

26. Ink composition according to claim 1, in which the vehicle consists of methyl ethyl ketone (MEK).

27. Substrate, support or object according to claim 21, in which the metal is aluminium or steel.

28. Substrate, support or object according to claim 21, in which the material containing cellulose is selected from the group consisting of cellophane, paper, optionally coated or glazed, cardboard and wood.

29. Substrate, support or object according to claim 21, in which the organic polymer is a thermoplastic polymer (“plastic”).

30. Substrate, support or object according to claim 29, in which the thermoplastic polymer is in the form of a film.

31. Substrate, support or object according to claim 29, in which the thermoplastic polymer is selected from the group consisting of PVDC, PVC, polyesters, PET, and polyolefins.

32. Substrate according to claim 22, in which the substrate is made of a material selected from the group consisting of cellophane, polyethylene, polypropylene, bi-oriented polypropylene, polyvinylchloride (PVC), plastified polyvinyl chloride, poly(vinylidene chloride) (PVDC), and rubber.

33. Ink composition according to claim 10, in which one or more organic solvent(s) other than ketones is (are) added in the vehicle in an amount of from 5 to 25%, with respect to the total weight of the vehicle.

Description

COMPARATIVE EXAMPLE

(1) In this example, a comparative ink composition has been prepared, not complying with the invention, which does not contain as binder a copolymer of vinylidene chloride, but vinylic and acrylics resins that are recommended for the formulation of inks for printing on substrates of PVDC type. The adherence conferred by these resins is thus among the best for such applications.

(2) The ink composition comprises, apart from said vinylic and acrylic resins, other ingredients, such as dyes, pigments, and other additives mentioned in Table I, in the proportions mentioned in Table I.

Examples 1 to 7

(3) In all these examples, ink compositions according to the invention are prepared which all contain as binder a copolymer of vinylidene chloride.

(4) These ink compositions comprise, apart from the copolymer of vinylidene chloride, other ingredients mentioned in Table I, such as dyes, pigments, and other additives, and optionally another resin different from the copolymer of vinylidene chloride, in the proportions mentioned in Table I.

(5) TABLE-US-00001 TABLE I INK COMPOSITIONS Constituents Comparative (percentages by weight) example N.sup.o1 N.sup.o2 N.sup.o3 N.sup.o4 N.sup.o5 N.sup.o6 N.sup.o7 Methyl ethyl ketone 60.55 60.5 83 88.8 87.5 87.5 80 61.3 Ethyl acetate 0.95 0.9 IXAN ® SGA-1 2 12 7.2 7.5 7.5 10 5 Acrylic resin (Neocryl B813) 2 Vinylic resin (Vinnol E15/45M) 6.5 5.9 2.5 Solvent Black 29 (Orasol ® black RLI) 5 Dispersion of C.I. Pigment Blue 60 at 60% in a vinylic resin 4 Dispersion of C.I. Pigment Red 202 at 70% in a vinylic resin 5 Dispersion of C.I. Pigment Yellow 83 at 70% in a vinylic 5 resin Dispersion of C.I. Pigment Black 7 at 8.8% in methyl ethyl 29.1 30.7 29.3 ketone Dispersion of C.I. Pigment White 6 at 75% in an acrylic resin 10 Tetrabutylammonium hexafluorophosphate 0.9 0.9 1 1 1 1 1 Surfactant Byk UV-3500 0.1 0.1 0.1 0.1 Viscosity (mPa .Math. s) 3.75 4.15 5.5 3.71 4.13 4.75 6.5 5.2 Conductivity (μS/cm) 960 957 1020 958 942 963 930 910 Particle size (Z-Average in nm) 132 NT* NA* 83.2 383 141 396 135 *NT: Not Tested *NA: Not Applicable

(6) The resin IXAN® SGA-1 is a soluble PVDC resin available from the firm SolVin (Solvay) of Brussels, Belgium.

(7) The resin Neocryl® B813 is a copolymer of ethyl methacrylate and of an acid monomer giving an acid number of 10 mg KOH/g manufactured by the firm DSM-Neoresin. Its Tg (glass transition temperature) is 64° C.

(8) The resin Vinnol E15/45M is a copolymer of vinyl chloride and vinyl acetate manufactured by the firm Wacker.

(9) The ink compositions according to Table I have been prepared by mixing the different resins, dyes and other additives in the solvent up to complete dissolution.

(10) All of these formulations have been tested in Markem-Imaje® printers of continuous jet type, and made it possible to obtain prints of excellent quality.

(11) In addition, markings, printings have been made with the ink compositions No 3 and No 7 on supports made of plastified PVDC, and subjected to a sterilisation in autoclave pressurised for 30 minutes at 12° C., and have not undergone any alteration.

(12) In the same conditions of sterilisation but placing in contact the PVDC support printed with these inks with the same unprinted support, a more important transfer of ink onto the non-printed support with the comparative ink than with the inks according to the invention may be observed.