Ink composition for continuous deflected ink jet printing notably on substrates made of organic polymers

Abstract

An ink composition for continuous deflected ink jet printing, which is liquid at ambient temperature, comprising: a solvent comprising, preferably consisting of, one or more organic solvent compound(s), and optionally water; a binder, comprising a saturated copolyester resin and a terpene-phenol resin; a compound having an ethylenically unsaturated double bond and a silicon chain; optionally, one or more dye(s) and/or pigment(s). A method for marking a substrate, support or object by spraying this ink composition on a surface of this substrate, support or object. A substrate, support or object, notably a polyolefin bottle or stopper, cap, for example made of polyethylene, provided with a marking obtained by drying, and/or absorption in the substrate, support or object, of this ink composition.

Claims

1. An ink composition for continuous deflected ink jet printing, which is liquid at ambient temperature, comprising: a) a solvent comprising one or more organic solvent compound(s), and optionally water; b) a binder, comprising a saturated copolyester resin and a terpene-phenol resin; c) a compound having an ethylenically unsaturated double bond and a silicon chain; d) optionally, one or more dye(s) and/or pigment(s).

2. An ink composition according to claim 1, which is free of halogenated compounds.

3. An ink composition according to claim 1, which comprises 0.1% to 30% by weight, of the total weight of the ink composition, of the saturated copolyester resin.

4. An ink composition according to claim 1, which comprises 0.1% to 15% by weight, of the total weight of the ink composition, of the terpene-phenol resin.

5. An ink composition according to claim 1, which comprises 0.01% to 5% by weight, of the total weight of the ink composition, of the compound having an ethylenically unsaturated double bond and a silicon chain.

6. An ink composition according to claim 1, in which the binder represents 1% to 45% by weight of the total weight of the ink composition.

7. An ink composition according to claim 1, comprising less than 10% by weight of water, compared to the total weight of the ink composition.

8. An ink composition according to claim 1, in which the solvent represents at least 20% by weight of the total weight of the ink composition.

9. An ink composition according to claim 1, in which the said organic solvent compound(s) comprise(s) a majority proportion by weight, compared to the total weight of the solvent, of one or more volatile organic solvent compound(s), and a minority proportion by weight, compared to the total weight of the solvent, of one or more non-volatile organic solvent compound(s).

10. An ink composition according to claim 1, in which the solvent comprises a majority amount by weight, compared to the total weight of the solvent of one or more solvent compound(s) selected from the group consisting of ketones with 3 to 10 carbon atoms.

11. An ink composition according to claim 10, further comprising one or more solvent compound(s) other than the ketone(s) in a minority total amount by weight, compared to the total weight of the solvent.

12. An ink composition according to claim 1, in which said dye(s) and/or pigment(s) is/are selected from the group consisting of C.I. Solvent Dyes, C.I. Pigments, fluorescent dyes, and optical brighteners.

13. An ink composition according to claim 1, in which the total amount of dye(s) and/or of pigment(s) is 0.05% to 25% by weight of the total weight of the ink composition.

14. An ink composition according to claim 1, further comprising one or more plasticiser(s).

15. An ink composition according to claim 1, which has an electrical conductivity greater than 5 S/cm at 20 C.

16. An ink composition according to claim 1, further comprising at least one conductivity salt.

17. An ink composition according to claim 16, in which the conductivity salt(s) is/are present in an amount of at least 0.05% by weight of the total weight of the ink composition.

18. An ink composition according to claim 1, further comprising one or more additive(s) selected from the group consisting of foaming agents; chemical stabilizers; ultraviolet stabilizers; surfactants; agents inhibiting corrosion; bactericides; fungicides; biocides and pH-regulating buffers.

19. A method for marking a substrate, support or object by spraying on a surface of this substrate, support or object an ink composition by the continuous deflected ink jet technique, in which the sprayed ink composition is the ink composition according to claim 1.

20. A method according to claim 19, in which, before spraying the ink composition, the surface of the substrate, support or object is not subjected to any surface treatment other than simple cleaning.

21. A substrate, support or object provided with a marking obtained by drying, and/or absorption in the substrate, support or object, of the ink composition according to claim 1.

22. A substrate, support or object, according to claim 21, which is made of metal; of glass; of ceramic; of a material containing cellulose; of organic polymer; of poly(methyl methacrylate) PMMA; of fabric; or of any other non-porous or porous substance, or of a composite of several of the above materials.

23. A substrate, support or object according to claim 22, which is a packaging or container, such as a bottle; or a stopper; made of a polyolefin.

24. An ink composition according to claim 12, wherein the C. I. Solvent Dyes are selected from the group consisting of C. I. Solvent Black 29, C. I. Solvent Black 27, C. I. Solvent Black 7, C. I. Solvent Black 28, C. I. Solvent Black 35, C. I. Solvent Blue 45, C. I. Solvent Blue 70, and C. I. Solvent Red 124, and the C. I. Pigments are selected from the group consisting of Pigment Blue 60, Pigment Blue 15, Pigment Black 7, and Pigment White 6.

25. An ink composition according to claim 16, wherein said at least one conductivity salt is selected from the group consisting of conductivity salts which are insoluble in water.

Description

EXAMPLES

(1) Ink compositions were prepared by mixing the products mentioned in table I below, in the stated proportions. The viscosities and conductivities of the obtained inks are also given in Table I below.

(2) The ink compositions of examples n 1 and n 2 are ink compositions according to the invention.

(3) The ink composition of the comparative example is an ink composition which contains no terpene-phenol resin, and which is not in accordance with the invention.

(4) TABLE-US-00001 TABLE I Constituents Comparative Example Example (percentages by mass) example N.sup.o1 N.sup.o2 Methyl-ethyl ketone 79.3 77.3 76.3 Terpene-Phenol resin 0 3 3 (Dertophene T of DRT) Polyester resin 14 14 14 (Vylon GK 250of Toyobo) Byk - UV 3500 0.7 Byk - Silclean 3710 0.7 0.7 Solvent Black 27 6 5 6 (Neozapon noir X51) Viscosity (mPa .Math. s) 3.86 4.35 4.44 Conductivity (S/cm). 730 525 651

(5) The inks prepared in this manner were deposited using Markem-Imaje 9040 printers, which use the technique of continuous deflected jet printing, on polyethylene bottles.

(6) On identical bottles, made of polyethylene, Markem-Imaje inks referenced 5182 and 5506, and the composition of the comparative example were deposited using Markem-Imaje 9040 printers. These inks act as controls or comparatives, since they are currently used for this polyethylene stoppers marking application.

(7) Comparative inks 5182 and 5506 include neither terpene-phenol resin, nor polyester resin. The ink of the comparative example contains no terpene-phenol resin.

(8) After 24 hours' drying, the markings on the polyethylene bottles were successively: rubbed with a finger by making 10 back and forth movements; subjected to soaking for several minutes in water or in soapy water, and the same rubbing test was repeated; rubbed with a piece of cotton soaked with ethanol; subjected to the scotch test.

(9) The results are summarised in the following table II:

(10) TABLE-US-00002 TABLE II Ink of the Ink of Ink of Comparative Comparative comparative example example Ink Ink 5506 Ink 5182 example N.sup.o1 N.sup.o2 Rubbing with a finger, 10 5 5 5 5 5 back and forth movements Rubbing with a finger, 10 5 5 5 5 5 back and forth movements after soaking in water Rubbing with a finger, 10 5 5 5 5 5 back and forth movements after soaking in water + soap Scotch adhesive strip 2 2 4-5 4-5 5 test Rubbing test with ethanol 4 1 4-5 5 5

(11) The results of the tests were marked using a marking scale ranging from 1 to 5.

(12) Mark:

(13) 5=marking unchanged

(14) 4=20% of marking damaged

(15) 3=50% of marking damaged or erased

(16) 2=80% of marking damaged or erased

(17) 1=Marking totally erased

(18) The inks of examples 1 and 2 in accordance with the invention show much better performance than comparative inks 5182 and 5506, and the ink of the comparative example.