AQUEOUS INKJET INK COMPOSITION

Abstract

An aqueous inkjet ink composition is disclosed and includes a dye based polymeric dispersant, an aqueous organic solvent, at least one additive and water for inkjet printing specific patterns on various texture products. The dye based polymeric dispersant is present in an amount of from 2 to 30 percent by weight of the total weight of the inkjet ink composition, the aqueous organic solvent is 15 to 65 percent by weigh, and the at least one additive less than 2 percent by weigh. The dye based polymeric dispersant, the aqueous organic solvent and the at least one additive are dissolved or dispersed in water. The present invention does not easily clog at printerhead nozzles and gets rid of a great deal of industrial waste water and a tedious and complex post treatment of water cleaning, thereby scaling down the manufacturing apparatus for digital fabric.

Claims

1. An aqueous inkjet ink composition, comprising: a dye based polymeric dispersant present in an amount of from 2 to 30 percent by weight of the total weight of the aqueous inkjet ink composition, comprising at least one dye polymer and an emulsifier, the at least one dye polymer present in an amount of from 1 to 20 percent by weight of the total weight of the aqueous inkjet ink composition, the at least one dye polymer having a particle size (D50) less than 100 nm; an aqueous organic solvent present in an amount of from 15 to 65 percent by weight of the total weight of the aqueous inkjet ink composition, comprising at least one of monool solvent, diol solvent, glycerol solvent, erythritol solvent, pentitol solvent, mannitol solvent, glycol sugar solvent, glycol ether solvent, pyrrolidone solvent and sulfoxide solvent; at least one additive present in an amount less than 2 percent by weight of the total weight of the aqueous inkjet ink composition, comprising at least one of fungicide, thickener, surfactant, antifoam, pH conditioning agent and chelating agent; and water for dissolving or dispersing the dye based polymeric dispersant, the aqueous organic solvent and the at least one additive, wherein the aqueous inkjet ink composition possesses viscosity in a range from 2 to 20 cps at 25° C., and surface tension in a range from 28 to 40 dyne/cm.

2. The inkjet ink composition as claimed in claim 1, wherein the dye polymer comprises at least one of polyurethane, polyimide, epoxy resin, polyester, acrylic, phenolic, polyether and melamine.

3. The inkjet ink composition as claimed in claim 2, wherein the dye polymer formed of polyurethane is obtained by a process of copolymerization of a reactive dye, isocyanate and a diol or polyol in a specific order of addition specified by a chemical reaction equation below, ##STR00014## where is chromophore group for the reactive dye, each of and is alkyl group or aryl group, and G is vinyl sulfone group or chlorotriazine group.

4. The inkjet ink composition as claimed in claim 2, wherein the dye polymer formed of polyimide is obtained through an addition reaction of a dye with hydroxyl group or a reactive dye containing amino group, and a pre-polymer or oligomer containing diisocyanate specified by a chemical reaction equation as below, ##STR00015## wherein is chromophore group, is a repeat unit of diisocyanate pre-polymer, and X is O (oxygen) or NH (nitro-hydrogen group).

5. The inkjet ink composition as claimed in claim 2, wherein the dye polymer formed of epoxy resin is obtained through a reaction process of a dye with hydroxyl group (OH) or a reactive dye containing amino group (NH2), and a pre-polymer or oligomer of epoxy resin specified by a chemical reaction equation as below, ##STR00016## wherein is chromophore group, is a repeat unit of pre-polymer of epoxy resin, and Y is O (oxygen) or NH (nitro-hydrogen group).

6. The inkjet ink composition as claimed in claim 2, wherein the dye polymer formed of polyimide is obtained through a reaction of copolymerization of a reactive dye, di-acid and di-amine specified by a chemical reaction equation as ##STR00017## wherein is chromophore group, each of and is alkyl group or aryl group, and G is vinyl sulfone group or chlorotriazine group.

7. The inkjet ink composition as claimed in claim 2, wherein the dye polymer formed of polyester is obtained through a reaction of copolymerization of a reactive dye, di-acid and diol specified by a chemical reaction equation as below, ##STR00018## wherein is chromophore group, each of and is alkyl group or aryl group, and G is vinyl sulfone group or chlorotriazine group.

8. The inkjet ink composition as claimed in claim 2, wherein the dye polymer formed of polyester is obtained through an addition reaction of a dye containing hydroxyl group or amino group, and pre-polymer or oligomer containing di-acid specified by a chemical reaction equation as below, ##STR00019## wherein is chromophore group, is a repeat unit of pre-polymer of di-acid, and Z is O (oxygen) or NH (nitro-hydrogen group).

9. The inkjet ink composition as claimed in claim 2, wherein the dye polymer formed of acrylic is obtained by first synthesizing a reactive dye having vinyl-based chromophore through diazotization, and then copolymerization with acrylic specified by a chemical reaction equation as below, ##STR00020## wherein is chromophore group, and each of R1-R5 is hydrogen (H) or alkyl group.

10. The inkjet ink composition as claimed in claim 2, wherein the dye polymer is obtained through a free radical polymerization of a dye containing vinyl group and monomer or oligomer containing vinyl group specified by a chemical reaction equation as below, ##STR00021## wherein each of R6, R9 and R10 is hydrogen (H) or alkyl group, each of R7 and R8 is hydrogen (H), alkyl group or alkyl derivative, and CHP is chromophore group.

Description

EXAMPLE 1

[0042] Polyvinylpyrrolidone and EDTA are dissolved in de-ionized water and well stirred for 30 minutes. The aqueous organic solvent is added and the mixture is stirred at room temperature for 15 minutes. At room temperature, polyurethane thickener (Anfong TW-710), polysiloxane surfactant (BYK-378), acetylene glycol surfactant (Surfynol 465) and triethanolamine are added according to Table 1-1, 1-2, 1-3 as below, and the mixture is stirred in high shear emulsification machine at 600 rpm for 30 minutes. The mixture is added by aqueous dye polyurethane dispersant, stirred for 1 hour, and finally filtered by a filter with a mesh of 0.8 μm to obtain various aqueous dye polymer inkjet inks as shown in Table 1-1, 1-2, 1-3.

TABLE-US-00001 TABLE 1-1 Sample Sample Sample Sample Sample Raw material 1 2 3 4 5 Dispersant of 20 20 20 20 20 aqueous black polyurethane dye 5 alcohol 20 — — — — diethylene glycol — 20 — — — 1,2-propanediol — — 20 20 20 1,2-hexanediol — — — — — glycerol 5 5 5 5 5 sorbitol — — — 2 2 ethylene glycol 10 10 — — — butyl ether diethylene glycol — — 10 8 — butyl ether propylene glycol — — — — 8 methyl ether Poly 0.5 0.5 0.5 0.5 0.5 vinylpyrrolidone BYK-378 0.1 0.1 0.1 0.1 0.1 EDTA 0.1 0.1 0.1 0.1 0.1 triethanolamine 0.2 0.2 0.2 0.2 0.2 De-ionized water 44.1 44.1 44.1 44.1 44.1 Viscosity (cps, 3.85 4.31 4.62 4.80 4.66 25° C.) Surface tension 26.7 26.9 26.9 27.2 27.0 (dyne/cm) Particle size (D50, 65 66 62 60 60 nm)

TABLE-US-00002 TABLE 1-2 Sample Sample Sample Sample Sample Raw material 6 7 8 9 10 Dispersant of 20 20 20 20 — aqueous black polyurethane dye 5 Dispersant of — — — — 15 aqueous yellow polyurethane dye 2 alcohol — — — 10 10 1,2-propanediol 20 20 15 15 15 1,2-hexanediol — 2 2 — 2 glycerol 5 — 5 5 5 sorbitol 3 8 8 10 10 propylene glycol — 5 — — — methyl ether dipropylene glycol 5 — — — — methyl ether pyrrolidone — — 5 — 5 dimethyl sulfoxide — — — 2 — Poly 0.5 0.25 — — — vinylpyrrolidone polyurethane — 1 1 1 1 (Anfong TW-710) BYK-378 0.1 0.1 0.02 0.02 0.02 Surfynol 465 — — 0.3 0.3 0.3 EDTA 0.1 0.1 0.1 0.1 0.1 triethanolamine 0.2 0.2 0.2 0.2 0.2 De-ionized water 44.1 43.35 43.38 36.38 36.38 Viscosity (cps, 4.40 5.08 4.43 5.50 5.18 25° C.) Surface tension 26.9 26.8 29.8 29.3 29.9 (dyne/cm) Particle size (D50, 66 62 65 62 76 nm)

TABLE-US-00003 TABLE 1-3 Sample Sample Sample Sample Sample Raw material 11 12 13 14 15 Dispersant of 15 — — — — aqueous yellow polyurethane dye 2 Dispersant of — 20 20 — — aqueous magenta polyurethane dye 3 Dispersant of — — — 20 20 aqueous blue polyurethane dye 4 diethylene glycol — — — — — 1,2-propanediol 20 15 15 15 15 1,2-hexanediol 2 2 2 2 2 glycerol 5 5 10 10 10 sorbitol 10 8 8 8 5 diethylene glycol — — — — 3 butyl ether propylene glycol 5 — — — — methyl ether pyrrolidone 5 5 5 5 5 dimethyl sulfoxide — — — — — Poly — — — — 0.25 vinylpyrrolidone polyurethane 1 1 1 1 1 (Anfong TW-710) BYK-378 0.02 0.02 0.02 0.02 0.02 Surfynol 465 0.3 0.3 0.3 0.3 0.3 EDTA 0.1 0.1 0.1 0.1 0.1 triethanolamine 0.2 0.2 0.2 0.2 0.2 De-ionized water 36.38 43.38 38.38 38.38 38.13 Viscosity (cps, 5.02 4.41 4.80 4.48 4.98 25° C.) Surface tension 30.8 31.2 30.7 30.13 30.5 (dyne/cm) Particle size (D50, 75 50 48 90 89 nm)

[0043] The resultant inkjet ink composition is evaluated by the following test items 1 to 8.

[0044] For item 1, viscosity test is performed by a rotational viscometer Brookfield DV-E and controlled at 25° C.

[0045] For item 2, surface tension is tested by a surface tensiometer CBVP-A3 manufactured by KYOWA INTERFACE SCIENCE CO., LTD.

[0046] For item 3, ink's capability of cleaning is tested by EPSON DX-5 printerhead, Mutoh 1304 in the machine mode of cleaning, wherein each time the printerhead is cleaned, the printerhead inkjets one test bar up to 20 times until breaking holes occur. Grade A: no breaking hole and no oblique inkjet for all 20 times. Grade B: no breaking hole and no oblique inkjet within 10 to 20 times. Grade C: any breaking hole or oblique inkjet within 10 times.

[0047] For item 4, ink's capability of anti-drying printerhead is tested by EPSON DX-5 printerhead, Mutoh 1304. After the pattern of inkjet is 10 m long, check the nozzle, move away the printerhead without stopping the system (without triggering the cleaning function), trigger the printerhead to inkjet after 30 minutes or 1 hour, and examine the flowing state of the ink to determine whether the printerhead is clogged or oblique inkjet occurs. Grade A: no breaking hole and no oblique inkjet within 1 hour. Grade B: no breaking hole and no oblique inkjet within 30 minutes. Grade C: any breaking hole or oblique inkjet within 30 minutes.

[0048] For item 5, ink's stability for inkjet is tested by EPSON DX-5 printerhead, Mutoh 1304. After the pattern of inkjet on a paper roll is 80 m long, determine whether any breaking hole, oblique inkjet or ink flying occurs. Grade A: no ink flying and no or slight oblique inkjet within 5 breaking holes during the 80 m test. Grade B: no ink flying and middle oblique inkjet within 10 breaking holes during the 80 m test. Grade C: ink flying or serious oblique inkjet within 10 breaking holes during the 80 m test.

[0049] For item 6, performance of inkjet pattern is tested by observing the inkjet pattern. Grade A: no bleeding and clear pattern. Grade B: somewhat bleeding at heavy ink region and fine pattern. Grade C: serious bleeding and poor pattern.

[0050] For item 7, test of high temperature stability is performed by pouring the ink into a mouth bottle, keeping the ink standstill at 45° C. for 8 weeks, and analyzing its viscosity and particle size after cooling down to room temperature. Grade A: variation of ink's viscosity and particle size less than 5%. Grade B: variation of ink's viscosity and particle size less than 10%. Grade C: variation of ink's viscosity and particle size larger than 10%.

[0051] For item 8, test of low temperature stability is performed by pouring the ink into a mouth bottle, keeping the ink standstill at −10° C. for 8 weeks, and analyzing its viscosity and particle size after warming up to room temperature. Grade A: variation of ink's viscosity and particle size less than 5%. Grade B: variation of ink's viscosity and particle size less than 10%. Grade C: variation of ink's viscosity and particle size larger than 10%.

[0052] For the evaluation test of the aqueous dye polymer inkjet ink such as ink's capability of cleaning, ink's stability for inkjet, ink's capability of anti-drying printerhead, performance of inkjet pattern, ink's thermal stability and test of low temperature stability, the test result is listed in Table 2-1, 2-2, 2-3.

TABLE-US-00004 TABLE 2-1 Sample Sample Sample Sample Sample Raw material 1 2 3 4 5 Test of capability of C B B B B cleaning Test of capability of C B B B B anti-drying printerhead Test of stability for C A B A B inkjet Test of performance B B A A A of inkjet pattern Test of high B A B A A temperature stability Test of low B B B B B temperature stability

TABLE-US-00005 TABLE 2-2 Sample Sample Sample Sample Sample Raw material 6 7 8 9 10 Test of capability of B B A A A cleaning Test of capability of B A A A A anti-drying printerhead Test of stability for A A A A A inkjet Test of performance A A A A B of inkjet pattern Test of high A A A B A temperature stability Test of low B A A B A temperature stability

TABLE-US-00006 TABLE 2-3 Sample Sample Sample Sample Sample Raw material 11 12 13 14 15 Test of capability of A A A A A cleaning Test of capability of A A A A A anti-drying printerhead Test of stability for A A A A A inkjet Test of performance A B A B A of inkjet pattern Test of high A A A A A temperature stability Test of low A A A A A temperature stability

[0053] From Table 2-1, 2-2, 2-3, the samples of the aqueous inkjet ink of the present invention fully meet all the evaluation items. The test sample 1 is added by alcohol with low boiling point such that the printerhead dries too fast, performance of cleaning the printerhead is poor and the length of inkjet is not sufficient. Such problems are slightly improved after adding glycol ether solvent with high boiling point, as shown by the samples 2-7. As for the samples 8-15, after pyrrolidone solvent and surfynol 465 are added, the test of cleaning capability is performed, and each time the printerhead is cleaned, the printerhead inkjets one test bar up to 20 times without any breaking hole or oblique inkjet. During the 80 m inkjet test, it results in no breaking hole, less than 5 oblique inkjet holes and no ink flying. In addition, after the printerhead is removed from the ink socket, the nozzle is not clogged by the printerhead and no oblique inkjet occurs after 1 hour. Further, adding the polyurethane thicker improves low temperature stability of the inkjet ink, as shown by the samples 7-15. When the dye based polymeric dispersant of the aqueous inkjet ink composition changes color, it needs to appropriately adjust the kind and the amount of the aqueous organic solvent so as to achieve the optimal exhibition of the ink, just like the samples 10, 12 and 14 compared to the samples 11, 13 and 15, respectively.

[0054] Furthermore, the aqueous inkjet ink composition of the present invention is applicable to the inkjet field such as inkjet printer. Through the inkjet printer, the desired patterns are not only inkjet printed on the paper, but also directly on various textile materials and after the heating/drying process is performed on the patterns, excellent brightness and vividness is resulted in as the dye ink. Thus, the textile semi-finished products using the aqueous inkjet ink composition exhibit bright and vivid color patterns without any additional cleaning step such as soap cleaning or water cleaning. The present invention avoids a great deal of waste water, and the inkjet ink is applicable to most textile materials such as cloth of cotton, linen, silk, wool, polyester, nylon and rayon. Particularly, the inkjet ink of the present invention possesses the features of excellent storage stability at high and low temperature, not easily clogging the printerhead and strong capability of cleaning.

[0055] Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.