阅读说明：本技术 一种高色牢度印花用水性聚氨酯分散体及其制备方法和用途 (Waterborne polyurethane dispersion for high-color-fastness printing and preparation method and application thereof ) 是由 于丽 王海梅 李卫飞 王少鹏 于 2020-11-25 设计创作，主要内容包括：本发明提供了一种用于提高印花色牢度的水性聚氨酯分散体及其制备方法和用途。该水性聚氨酯分散体通过将染料分子在预聚阶段接枝到分子链上,与后扩链前添加的动物胶类物质发生协同效应,提高染料与分子链的结合,达到印花高色牢度的要求,硬脂酸酯类的加入,有利于进一步提高印花的色牢度以及滑爽度。(The invention provides an aqueous polyurethane dispersion for improving printing color fastness and a preparation method and application thereof. According to the aqueous polyurethane dispersion, dye molecules are grafted to a molecular chain in a prepolymerization stage, a synergistic effect is generated with an animal glue substance added before chain extension, the combination of the dye and the molecular chain is improved, the requirement of high printing color fastness is met, and the addition of the stearate is beneficial to further improving the color fastness and smoothness of printing.)

1. An aqueous polyurethane dispersion for high-color-fastness printing comprises the following raw materials which are prepared by reaction, based on solid content weight:

a. polyisocyanates, added in an amount of 18 to 28% by weight, preferably 20 to 25% by weight;

b. a polyol, added in an amount of 28 to 41% by weight, preferably 32 to 38% by weight;

c. hydroxyl-containing pigments in an amount of from 20 to 30% by weight, preferably from 20 to 25% by weight;

d. a small molecular polyol chain extender, the addition amount is 1-6 wt%, preferably 1.5-4 wt%;

e. 1-6% of hydrophilic chain extender containing active hydrogen, preferably 2-5% by weight;

f. animal glue, added in 10-20 wt%, preferably 10-15 wt%;

g. the addition amount of the small molecular polyamine chain extender containing active hydrogen is 1-6 wt%, preferably 2-5 wt%.

2. Dispersion according to claim 1, characterized in that component a is selected from aliphatic and/or cycloaliphatic isocyanates, preferably one or more of isophorone diisocyanate, 1, 6-hexyl diisocyanate, dicyclohexylmethane diisocyanate and tetramethylxylylene diisocyanate, and/or:

the component b is polyhydric alcohol with the number average molecular weight of 100-.

3. Dispersion according to claim 1, characterized in that component c is selected from one or more of rose bengal B, acid red 52, trisodium 8-hydroxy-1, 3, 6-pyrenetrisulfonate.

4. Dispersion according to claim 1, characterized in that component d is selected from one or more of ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, diethylene glycol, neopentyl glycol, 1, 6-hexanediol, 2, 3-butanediol, neopentyl glycol, diethylene glycol and 1, 4-cyclohexanedimethanol, preferably one or more of 1, 4-butanediol and 1, 6-hexanediol, and/or:

component e is selected from one or more of dimethylolpropionic acid, dimethylolbutyric acid, dimethylolpentanoic acid and dimethyloloctanoic acid.

5. The dispersion of claim 1, wherein component f is selected from one or more of bovine bone glue, gelatin.

6. Dispersion according to claim 1, characterized in that component g is selected from one or more of ethylenediamine, propylenediamine, hexamethylenediamine, 4-diphenylmethanediamine, hydroxyethylethylenediamine, di-n-butylamine, isophoronediamine and 1, 3-bis [ (trimethylol) methylamino ] propane, preferably one or more of 1, 3-bis [ (trimethylol) methylamino ] propane, hydroxyethylethylenediamine and isophoronediamine.

7. The dispersion of any one of claims 1 to 6, wherein the raw materials of the dispersion further comprise one or more of glyceryl stearate, sorbitan monostearate, and ethylene glycol distearate, and the addition amount is 1 to 6 wt%.

8. A dispersion according to any one of claims 1 to 7, characterized in that the solid content of the dispersion is 45 to 55% by weight and the particle size of the dispersion is 50 to 200 nm.

9. A process for preparing a dispersion according to any one of claims 1 to 8, comprising:

(1) mixing the components a, b and c for reaction to generate a prepolymer;

(2) adding the components d and e and a catalyst into the prepolymer for chain extension, and cooling after theoretical NCO% is reached;

(3) adding deionized water for dispersion;

(4) adding the components f and h, adding the component g for chain extension to obtain an aqueous polyurethane dispersion product,

the component h is selected from one or more of glyceryl stearate, sorbitan monostearate and ethylene glycol distearate.

10. Use of the dispersion according to any one of claims 1 to 8 or of the dispersion prepared by the process according to claim 9 in fields of application including clothing, footwear, inks.

Technical Field

The invention belongs to the field of waterborne polyurethane materials, and particularly relates to a waterborne polyurethane dispersion for improving printing color fastness, and a preparation method and application thereof.

Background

The printing is carried out by adopting the aqueous polyurethane dispersion, only drying and washing are needed, the process is simple, the discharge of solvent and sewage can be reduced, and the requirement of environmental protection is met. The aqueous polyurethane dispersion can form a compact and transparent film on the surface of the fabric, and the film has good adhesiveness and elasticity.

With the improvement of living standard of people, the requirements of people on clothes and shoe materials are higher and higher, so that the color fastness of printing on the clothes and the shoe materials becomes one of concerns, the printing process is to add color paste into printing resin prepared by physical dispersion of resin for application, but most of the printing obtained by the method has poor color fastness. Therefore, a resin which can improve the fastness of printing has been developed.

CN108867113A discloses a pigment printing adhesive and a preparation method thereof, wherein polytetrahydrofuran glycol, hydroxyl-terminated polydimethylsiloxane, polycarbonate glycol, polycaprolactone, polypropylene glycol and dimethylolpropionic acid are used as soft segments, MDI and IPDI are used as hard segments to prepare a water-based paint, and then chitin, furcellaran, sodium alginate and fatty amine polyoxyethylene ether are added and mixed uniformly to prepare paint color paste. The method does not combine the pigment and the resin to generate chemical bonds, and the color fastness still has problems in the application process. Therefore, the problem of color fastness of printing still needs to be solved.

Disclosure of Invention

The invention aims to provide an aqueous polyurethane dispersion for improving the color fastness of printing. According to the aqueous polyurethane dispersion, dye molecules are grafted to a molecular chain in a prepolymerization stage and generate a synergistic effect with animal glue added before chain extension, so that the effect of better combining resin and dye is achieved, and the requirement of high color fastness of the resin in a printing direction is met; in a preferred scheme, the addition of the stearate is beneficial to further improving the color fastness and the smoothness of printing.

In order to achieve the purpose, the invention adopts the following technical scheme:

an aqueous polyurethane dispersion for improving printing color fastness comprises the following raw materials:

a. polyisocyanates, added in an amount of 18 to 28% by weight, preferably 20 to 25% by weight;

b. a polyol, added in an amount of 28 to 41% by weight, preferably 32 to 38% by weight;

c. hydroxyl-containing pigments in an amount of from 20 to 30% by weight, preferably from 20 to 25% by weight;

d. a small molecular polyol chain extender, the addition amount is 1-6 wt%, preferably 1.5-4 wt%;

e. 1-6% of hydrophilic chain extender containing active hydrogen, preferably 2-5% by weight;

f. animal glue, added in 10-20 wt%, preferably 10-15 wt%;

g. the addition amount of the small molecular polyamine chain extender containing active hydrogen is 1-6 wt%, preferably 2-5 wt%;

the dosage percentage of the raw materials is based on the solid content weight of the waterborne polyurethane resin.

As a preferred embodiment, the raw materials of the aqueous polyurethane dispersion may further include a component h: the addition amount of one or more of glycerol stearate, sorbitan monostearate and ethylene glycol distearate is 1-6 wt%, preferably 2-5 wt%, and the addition of the above-mentioned stearate is favorable for further improving the colour fastness and smoothness of printing.

In the present invention, component a is selected from aliphatic and/or alicyclic isocyanates, preferably one or more of isophorone diisocyanate, 1, 6-hexyl diisocyanate, dicyclohexylmethane diisocyanate and tetramethylxylylene diisocyanate, more preferably dicyclohexylmethane diisocyanate and isophorone diisocyanate, and these two isocyanates can act synergistically to improve the overall performance of the dispersion.

In the invention, the component b is polyol with the number average molecular weight of 100-; one or more of polypropylene glycol diol and/or polytetrahydrofuran diol with the number average molecular weight of 300-3000 are preferable.

In the invention, the component c is selected from one or more of acid rose bengal B, acid red 52 and trisodium 8-hydroxy-1, 3, 6-pyrenetrisulfonate.

In the invention, the component d is a small molecular polyol with the molecular weight of 20-100, and is selected from one or more of ethylene glycol, 1, 3-propylene glycol, 1, 4-butanediol, diethylene glycol, neopentyl glycol, 1, 6-hexanediol, 2, 3-butanediol, neopentyl glycol, diethylene glycol and 1, 4-cyclohexanedimethanol, and preferably 1, 4-butanediol and/or 1, 6-hexanediol.

In the present invention, component e is selected from one or more of dimethylolpropionic acid, dimethylolbutyric acid, dimethylolvaleric acid and dimethyloloctanoic acid, preferably dimethylolbutyric acid.

In the invention, the component f is selected from one or more of bovine bone glue and gelatin.

In the present invention, the component g is one or more selected from the group consisting of ethylenediamine, propylenediamine, hexamethylenediamine, 4-diphenylmethanediamine, hydroxyethylethylenediamine, di-n-butylamine, isophoronediamine and 1, 3-bis [ (trimethylol) methylamino ] propane, preferably one or more selected from the group consisting of 1, 3-bis [ (trimethylol) methylamino ] propane, hydroxyethylethylenediamine and isophoronediamine.

In the invention, the solid content of the dispersion is 45-55 wt%, preferably 50-55 wt%, and the particle size of the dispersion is 50-200nm, preferably 100-150 nm.

In the invention, the preparation method of the aqueous polyurethane dispersion comprises the following preparation steps:

(1) mixing the components a, b and c for reaction at the temperature of 80-95 ℃ to generate a prepolymer;

(2) adding the components d and e, acetone and a catalyst into the prepolymer for chain extension, wherein the reaction temperature is 75-85 ℃, the temperature is reduced after theoretical NCO% is reached, and acetone is added for dilution;

(3) adding deionized water under high-speed shearing for dispersing;

(4) and (3) adding the components f and h, adding the component g, chain extending, and removing acetone to obtain the aqueous polyurethane dispersion product.

In the process of the present invention, the catalyst is selected from organic bismuth catalysts, such as bismuth isooctanoate, bismuth laur acid, bismuth neodecanoate, preferably one or more of organic bismuth Coscat83, organic bismuth 1610, organic bismuth 2010, organic bismuth 2810 and organic bismuth 2808.

In the invention, the dispersoid prepared by the method can be used in the fields of clothing, shoe materials, printing ink and the like with higher requirements on printing color fastness.

The positive effects of the invention are mainly reflected in the following aspects:

according to the waterborne polyurethane dispersion, dye molecules are grafted onto a molecular chain at a prepolymerization stage and generate a synergistic effect with the animal glue added before chain extension, so that the effect of better combination of resin and dye is achieved, the requirement of high color fastness of the resin in a printing direction is met, and the addition of the stearate is beneficial to further improvement of the color fastness and the smoothness of printing.

Detailed Description

The test method in the invention is as follows:

the particle size test method comprises the following steps: a malvern particle size instrument was used.

Viscosity test method: a BROOKFIELD viscometer, rotor No. 3, at 30rpm was used.

Color fastness to rubbing: measured according to GB/T3920-2008 ' color fastness to rubbing ' of textile color fastness test '.

Fastness to soaping: according to GB/T-2008 ' color fastness to soaping ' of textile color fastness test '.

Smoothness degree: and selecting 10 persons, sequentially grading the printing samples, and taking an average value.

The construction process for preparing the textile printing by using the dispersion is as follows:

manual screen printing, screen printing or rotary screen printing is adopted, and four knives are used twice. The samples were tested after curing in an oven at 50 ℃ for 24 h.

The fabric printing construction formula is as follows:

the raw materials used in the examples were as follows:

HMDI (dicyclohexylmethane diisocyanate, having an NCO% content of about 32.0%, Vanhua Chemicals Ltd.);

IPDI (isophorone diisocyanate, NCO% content about 37.8%, Vanhua chemical group Co., Ltd.);

PPG2000 (Polypropylene glycol, hydroxyl number 56mgKOH/g, number average molecular weight ≈ 2000, functionality of 2, great east Chemicals);

PTMG2000 (polytetrahydrofuran ether glycol, hydroxyl value 56mgKOH/g, number average molecular weight 2000, functionality of 2, Tahitawa Daochien);

PTMG1000 (polytetrahydrofuran ether glycol, hydroxyl value 112mgKOH/g, number average molecular weight 1000, functionality of 2, dawsonia macrochemical);

trisodium 8-hydroxy-1, 3, 6-pyrenetrisulphonate (Shanghai Yan science and technology development Co., Ltd.)

Acid rose oxide B (Tianjin million chemical Co., Ltd.)

Ox bone glue (Hengshui Qianlong gelatin science and technology limited)

Gelatin (Hengshui Qianlong gelatin Tech Co., Ltd.)

HDO (1, 6-hexanediol, BASF, germany);

BDO (1, 4-butanediol, BASF, Germany);

dimethylolbutyric acid (Bailingwei science and technology Co., Ltd., analytical purity)

IPDA (isophoronediamine, BASF, Germany);

EDA (ethylenediamine, BASF, germany);

1, 3-bis [ (trihydroxymethyl) methylamino ] propane (chain extender, Dalian Meiren Biotech Co., Ltd.);

organic bismuth Coscat 83: leading chemical company, analytical purity, USA

A801 (alkali thickening thickener, Wanhua chemical)Group stocks, ltd);

u605 (polyurethane type associative thickener, Vanhua chemical group Co., Ltd.).

Example 1

30g of IPDI, 20g of HDI, 35g of PPG2000, 20g of PTMG2000, 15g of PTMG1000, and 43g of trisodium 8-hydroxy-1, 3, 6-pyrenetrisulfonate were charged into a four-necked flask equipped with a reflux condenser, a thermometer, and mechanical stirring, and after reacting at 80 ℃ for 1 hour, the NCO content was measured to obtain a prepolymer.

And (3) cooling to 60 ℃, adding 2g of BDO, 2g of HDO, 4.7g of dimethylolbutyric acid, 0.3g of organic bismuth Coscat83 and 40g of acetone for dilution, stirring uniformly, heating to 80 ℃ for reaction, and stopping the reaction when the reaction reaches theoretical NCO%. Cooling to 60 ℃, adding 50g of acetone for dilution, stirring and mixing for 5min, and continuously cooling to 30-35 ℃.

173g of deionized water was added for dispersion.

Adding 30g of gelatin, stirring uniformly, diluting 5g of isophorone diamine and 6g of 1, 3-bis [ (trihydroxymethyl) methylamino ] propane with 40g of deionized water, slowly adding into the system, reacting for 5min at the constant temperature of 35 ℃, distilling the prepared emulsion under reduced pressure to remove acetone, and obtaining the blue-light-evident waterborne polyurethane emulsion with the particle size of 110 nm.

Example 2

Into a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer were charged 20g of IPDI, 23g of HDI, 20g of PPG2000, 60g of PTMG1000 and 45g of acid rose bengal B, and after reacting at 80 ℃ for 1 hour, the NCO content was measured to obtain a prepolymer.

And cooling to 60 ℃, adding 4g of BDO, 4g of HDO, 9.2g of dimethylolbutyric acid, 0.8 g of organic bismuth Coscat83 and 40g of acetone for dilution, uniformly stirring, heating to 80 ℃, and stopping reaction when the reaction reaches theoretical NCO%. Cooling to 60 ℃, adding 50g of acetone for dilution, stirring and mixing for 5min to fully mix the prepolymer and the acetone, and continuously cooling to 30-35 ℃.

173g of deionized water was added for dispersion.

Adding 22g of bovine bone glue, uniformly stirring, diluting 2g of isophorone diamine and 3g of 1, 3-bis [ (trihydroxymethyl) methylamino ] propane with 40g of deionized water, slowly adding into the system, reacting at the constant temperature of 35 ℃ for 5min, and distilling the prepared emulsion under reduced pressure to remove acetone to obtain the blue-light-evident waterborne polyurethane emulsion with the particle size of 120 nm.

Example 3

Into a four-necked flask equipped with a reflux condenser, a thermometer and mechanical stirring, 15g of IPDI, 38g of HDI, 35g of PPG2000, 35g of PTMG2000, 15g of PTMG1000, 53g of trisodium 8-hydroxy-1, 3, 6-pyrenetrisulfonate were charged, reacted at 80 ℃ for 1 hour, and NCO content was measured to obtain a prepolymer.

And cooling to 60 ℃, adding 1g of BDO, 2.5g of HDO, 4.5g of dimethylolbutyric acid, 0.4 g of organic bismuth Coscat83 and 40g of acetone for dilution, stirring uniformly, heating to 80 ℃, and stopping the reaction when the theoretical NCO% is reached. Cooling to 60 ℃, adding 50g of acetone for dilution, stirring and mixing for 5min to fully mix the prepolymer and the acetone, and continuously cooling to 30-35 ℃.

148g of deionized water were added for dispersion.

Adding 24.6g of bovine bone glue, uniformly stirring, diluting 3g of isophorone diamine 3g of 1, 3-bis [ (trihydroxymethyl) methylamino ] propane with 40g of deionized water, slowly adding the diluted solution into a system, reacting at the constant temperature of 35 ℃ for 5min, and distilling the prepared emulsion under reduced pressure to remove acetone to obtain the blue-light-evident waterborne polyurethane emulsion with the particle size of 100 nm.

Example 4

50g of IPDI, 70 PPG2000 and 49.2g of trisodium 8-hydroxy-1, 3, 6-pyrenetrisulfonate were added to a four-necked flask equipped with a reflux condenser, a thermometer and mechanical stirring, and after reacting at 80 ℃ for 1 hour, the NCO content was measured to obtain a prepolymer.

And cooling to 60 ℃, adding 6g of BDO, 5g of dimethylolbutyric acid, 0.8 g of organic bismuth Coscat83 and 40g of acetone for dilution, uniformly stirring, heating to 80 ℃, and stopping reaction when the reaction reaches theoretical NCO%. Cooling to 60 ℃, adding 50g of acetone for dilution, stirring and mixing for 5min to fully mix the prepolymer and the acetone, and continuously cooling to 30-35 ℃.

173g of deionized water was added for dispersion.

Adding 22g of bovine bone gelatin and 5g of sorbitan monostearate, stirring uniformly, diluting 5g of 1, 3-bis [ (trihydroxymethyl) methylamino ] propane with 40g of deionized water, slowly adding the diluted solution into a system, reacting at the constant temperature of 35 ℃ for 5min, and distilling the prepared emulsion under reduced pressure to remove acetone to obtain the blue-light-evident waterborne polyurethane emulsion with the particle size of 100 nm.

Example 5

43g of IPDI, 72.6g of PTMG1000 and 43g of acid rose bengal B were charged into a four-necked flask equipped with a reflux condenser, a thermometer and mechanical stirring, and reacted at 80 ℃ for 1 hour, and then the NCO content was measured to obtain a prepolymer.

Cooling to 60 ℃, adding 4g of HDO, 10g of dimethylolbutyric acid, 0.4 g of organic bismuth Coscat83 and 40g of acetone for dilution, uniformly stirring, heating to 80 ℃, and stopping reaction when the reaction reaches theoretical NCO%. Cooling to 60 ℃, adding 50g of acetone for dilution, stirring and mixing for 5min to fully mix the prepolymer and the acetone, and continuously cooling to 30-35 ℃.

148g of deionized water were added for dispersion.

Adding 22g of gelatin, 4g of glycerol stearate and 4g of ethylene glycol distearate, uniformly stirring, diluting 10g of isophorone diamine with 40g of deionized water, slowly adding into the system, reacting at the constant temperature of 35 ℃ for 5min, and distilling the prepared emulsion under reduced pressure to remove acetone to obtain the blue-light-evident waterborne polyurethane emulsion with the particle size of 100 nm.

Comparative example 1

Into a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer were charged 30g of IPDI, 20g of HDI, 35g of PPG2000, 20g of PTMG2000 and 15g of PTMG1000, reacted at 80 ℃ for 1 hour, and NCO content was measured to obtain a prepolymer.

And cooling to 60 ℃, adding 2g of BDO, 2g of HDO, 4.7g of dimethylolbutyric acid, 0.3g of organic bismuth Coscat83 and 40g of acetone for dilution, uniformly stirring, heating to 80 ℃, and stopping reaction when the reaction reaches theoretical NCO%. Cooling to 60 ℃, adding 50g of acetone for dilution, stirring and mixing for 5min to fully mix the prepolymer and the acetone, and continuously cooling to 30-35 ℃.

173g of deionized water was added for dispersion.

Adding 30g of gelatin, uniformly stirring, diluting 5g of isophorone diamine and 6g of 1, 3-bis [ (trihydroxymethyl) methylamino ] propane with 40g of deionized water, slowly adding the diluted materials into a system, reacting for 5min at a constant temperature of 35 ℃, adding 43g of 8-hydroxy-1, 3, 6-pyrene trisulfonic acid trisodium, uniformly stirring, and distilling the prepared emulsion under reduced pressure to remove acetone to obtain the blue-light-evident waterborne polyurethane emulsion with the particle size of 100 nm.

Comparative example 2

Into a four-necked flask equipped with a reflux condenser, a thermometer and a mechanical stirrer were charged 25.8g of IPDI, 17g of HDI, 30g of PPG2000, 17g of PTMG2000, 12.9g of PTMG1000, 37g of trisodium 8-hydroxy-1, 3, 6-pyrenetrisulfonate, and after reacting at 80 ℃ for 1 hour, the NCO content was measured to obtain a prepolymer.

And cooling to 60 ℃, adding 1.7g of BDO, 1.7g of HDO, 4g of dimethylolbutyric acid, 0.26 g of organic bismuth Coscat83 and 40g of acetone for dilution, stirring uniformly, heating to 80 ℃, and stopping reaction when the reaction reaches theoretical NCO%. Cooling to 60 ℃, adding 50g of acetone for dilution, stirring and mixing for 5min to fully mix the prepolymer and the acetone, and continuously cooling to 30-35 ℃.

116.7g of deionized water was added for dispersion.

4.3g of isophorone diamine and 5g of 1, 3-bis [ (trihydroxymethyl) methylamino ] propane are diluted by 40g of deionized water, slowly added into the system, reacted for 5min at the constant temperature of 35 ℃, added with the prepared emulsion, decompressed and distilled to remove acetone, thus obtaining the blue-light-evident waterborne polyurethane emulsion with the particle size of 110 nm.

Textile prints were prepared using the dispersions of the examples and comparative examples according to the aforementioned textile print construction recipe, and the properties of the constructed samples are shown in table 1:

TABLE 1 Properties of dispersions prepared on textile prints in the examples and comparative examples

Grading: grades 1-5, with grade 1 being the worst and grade 5 being the best.