阅读说明：本技术 一种由水性聚氨酯处理棉织物的分散染料染色方法 (Disperse dye dyeing method for treating cotton fabric by using waterborne polyurethane ) 是由 王运利 郭恒 徐卫林 胡金榜 张稳 黄宏博 韩宗保 于 2019-12-18 设计创作，主要内容包括：本发明涉及纺织技术领域,公开了一种由水性聚氨酯处理棉织物的分散染料染色方法,该方法包括以下步骤：(1)免烫预处理：使用水性聚氨酯作为免烫整理剂对棉织物进行免烫整理,所述水性聚氨酯的数均分子量为3000-50000；(2)分散染料染色：使用分散染料配制剂对经步骤(1)预处理后得到的棉织物进行分散染料染色。该方法能有效地使用分散染料对棉织物进行染色,工艺简单,生产过程污水治理成本低,对环境友好。(The invention relates to the technical field of textile, and discloses a disperse dye dyeing method for treating cotton fabric by aqueous polyurethane, which comprises the following steps: (1) non-ironing pretreatment: the method comprises the following steps of (1) carrying out non-ironing finishing on cotton fabrics by using waterborne polyurethane as a non-ironing finishing agent, wherein the number average molecular weight of the waterborne polyurethane is 3000-50000; (2) dyeing with a disperse dye: and (3) dyeing the cotton fabric pretreated in the step (1) by using a disperse dye preparation through a disperse dye. The method can effectively dye the cotton fabric by using the disperse dye, has simple process and low sewage treatment cost in the production process, and is environment-friendly.)

1. A disperse dye dyeing method for treating cotton fabric by aqueous polyurethane is characterized by comprising the following steps:

(1) non-ironing pretreatment: the method comprises the following steps of (1) carrying out non-ironing finishing on cotton fabrics by using waterborne polyurethane as a non-ironing finishing agent, wherein the number average molecular weight of the waterborne polyurethane is 3000-50000;

(2) dyeing with a disperse dye: and (3) dyeing the cotton fabric pretreated in the step (1) by using a disperse dye preparation through a disperse dye.

2. The method according to claim 1, wherein in step (1), the process of permanent press finishing comprises: soaking the cotton fabric in finishing liquid containing waterborne polyurethane at two times and rolling the cotton fabric at two times to ensure that the liquid carrying rate is 70-80%, drying the cotton fabric for 3-10 minutes at 75-85 ℃, baking the cotton fabric for 1.5-3 minutes at 150-170 ℃, and then taking out the treated cotton fabric to carry out water washing and drying at 75-85 ℃.

3. The method according to claim 2, wherein the finishing liquid containing the aqueous polyurethane further contains a penetrant and an auxiliary agent, wherein the concentration of the aqueous polyurethane is 50-100g/L, the concentration of the penetrant is 0.1-2g/L, and the concentration of the auxiliary agent is 10-40 g/L.

4. The method as claimed in claim 3, wherein the concentration of the aqueous polyurethane is 60-80g/L, the concentration of the penetrating agent is 0.2-1g/L, and the concentration of the auxiliary agent is 20-30 g/L.

5. The method of claim 3, wherein the adjuvant is at least one of tetraisobutyl titanate, zinc naphthenate, and iron octoate.

6. The method according to any one of claims 1 to 5, wherein in the step (2), the step of dyeing with the disperse dye comprises: adding the cotton fabric into a disperse dye preparation, wherein the bath ratio is 1:10-50, the initial dyeing temperature is 30-60 ℃, then heating up at the heating rate of 1-3 ℃/min, keeping the temperature and dyeing for 40-80min after the temperature reaches 70-100 ℃, then cooling down at the cooling rate of 1-3 ℃/min, taking out the fabric after the temperature is reduced to below 50 ℃, and reducing and cleaning.

7. The method according to claim 6, wherein the disperse dye preparation is a disperse suspension of disperse dye in water, and the amount of the disperse dye is 0.5-5% of the mass of the cotton fabric;

preferably, the disperse dye is at least one of disperse blue, disperse black, disperse gray, disperse red, disperse violet, disperse yellow and disperse orange.

8. The method of claim 7, wherein the disperse dye formulation further comprises a leveling agent;

preferably, the leveling agent is used in an amount of 0.05% to 0.5% by mass of the disperse dye formulation.

9. The method according to claim 6, wherein the solution for reductive cleaning is a mixed aqueous solution of sodium hydrosulfite and caustic soda;

preferably, the concentration of sodium hydrosulfite in the solution for reduction cleaning is 0.5-4 g/L;

preferably, the concentration of caustic soda in the solution used for the reductive cleaning is 0.5-4 g/L.

10. The method of claim 9, wherein the reductive cleaning conditions comprise: the bath ratio is 1:10-30, the temperature is 70-100 deg.C, and the time is 5-30 min.

Technical Field

The invention relates to the technical field of spinning, in particular to a disperse dye dyeing method for treating cotton fabric by aqueous polyurethane.

Background

The pure cotton fabric is produced by using cotton as a raw material through a textile process, and has the characteristics of moisture absorption, moisture retention, heat resistance, alkali resistance, sanitation and the like. The pure cotton fabric is comfortable to wear and good in skin friendliness, is widely favored by people, and is particularly considered as the safest fabric in infant clothes.

In the existing dyeing field, the cotton fabric is dyed by using reactive dyes most commonly, but in the reactive dye dyeing process, in order to enable the dyes to have enough affinity to cotton fibers, a large amount of electrolytes (salts) need to be added, and meanwhile, a large amount of alkali needs to be added to provide a needed alkaline environment for dyeing, so that the difficulty of treating the reactive dye dyeing wastewater is greatly increased, and the dyeing cost is also increased. Meanwhile, the active dye is limited by the color spectrum, and has fewer beautiful colors and fluorescent color systems, so that the increasingly growing aesthetic requirements of people cannot be met.

Another common dyeing method is disperse dye dyeing, which is commonly used for dyeing terylene because of its excellent properties of bright and rich color, fastness to washing, rubbing and sun, mildness to skin, and environmental friendliness, and its dyeing process usually requires higher temperature or pressure, for example, the dyeing condition is heating to 130 ℃ and pressurizing or hot melting to 180 ℃. However, since there are many hydrophilic hydroxyl groups on cotton fiber, and the disperse dye is a nonionic dye with low water solubility and strong hydrophobicity, and has no affinity to cotton fiber, it is difficult to dye the cotton fiber with the disperse dye.

Disclosure of Invention

The invention aims to overcome the problems existing in the process of dyeing cotton fabrics by using the reactive dye and provides a disperse dye dyeing method for treating cotton fabrics by using waterborne polyurethane.

In order to achieve the above object, the present invention provides a disperse dye dyeing method for treating cotton fabric with aqueous polyurethane, comprising the steps of:

(1) non-ironing pretreatment: the method comprises the following steps of (1) carrying out non-ironing finishing on cotton fabrics by using waterborne polyurethane as a non-ironing finishing agent, wherein the number average molecular weight of the waterborne polyurethane is 3000-50000;

(2) dyeing with a disperse dye: and (3) dyeing the cotton fabric pretreated in the step (1) by using a disperse dye preparation through a disperse dye.

Preferably, in step (1), the process of permanent press finishing comprises: soaking the cotton fabric in finishing liquid containing waterborne polyurethane at two times and rolling the cotton fabric at two times to ensure that the liquid carrying rate is 70-80%, drying the cotton fabric for 3-10 minutes at 75-85 ℃, baking the cotton fabric for 1.5-3 minutes at 150-170 ℃, and then taking out the treated cotton fabric to carry out water washing and drying at 75-85 ℃.

Preferably, the finishing liquid containing the waterborne polyurethane further contains a penetrating agent and an auxiliary agent, wherein the concentration of the waterborne polyurethane is 50-100g/L, the concentration of the penetrating agent is 0.1-2g/L, and the concentration of the auxiliary agent is 10-40 g/L.

Preferably, the concentration of the waterborne polyurethane is 60-80g/L, the concentration of the penetrating agent is 0.2-1g/L, and the concentration of the auxiliary agent is 20-30 g/L.

Preferably, the auxiliary agent is at least one of tetraisobutyl titanate, zinc naphthenate and iron octoate.

Preferably, in the step (2), the step of dyeing with the disperse dye includes: adding the cotton fabric into a disperse dye preparation, wherein the bath ratio is 1:10-50, the initial dyeing temperature is 30-60 ℃, then heating up at the heating rate of 1-3 ℃/min, keeping the temperature and dyeing for 40-80min after the temperature reaches 70-100 ℃, then cooling down at the cooling rate of 1-3 ℃/min, taking out the fabric after the temperature is reduced to below 50 ℃, and reducing and cleaning.

Preferably, the disperse dye formulation is a disperse suspension of disperse dye in water, and the amount of the disperse dye is 0.5-5% of the mass of the cotton fabric.

Preferably, the disperse dye is at least one of disperse blue, disperse black, disperse gray, disperse red, disperse violet, disperse yellow and disperse orange.

Preferably, a leveling agent is also included in the disperse dye formulation.

Further preferably, the leveling agent is used in an amount of 0.05% to 0.5% by mass of the disperse dye formulation.

Preferably, the solution used for reduction cleaning is a mixed aqueous solution of sodium hydrosulfite and caustic soda.

Further preferably, the concentration of the sodium hydrosulfite in the solution for reduction cleaning is 0.5-4 g/L.

Further preferably, the concentration of caustic soda in the solution used for the reductive cleaning is 0.5 to 4 g/L.

Preferably, the conditions of the reductive cleaning include: the bath ratio is 1:10-30, the temperature is 70-100 deg.C, and the time is 5-30 min.

According to the disperse dye dyeing method for treating the cotton fabric by using the waterborne polyurethane, the waterborne polyurethane is firstly used for carrying out non-ironing finishing on the cotton fabric, so that the non-ironing performance of the cotton fabric is improved; on the other hand, in the non-ironing finishing process, the water-based polyurethane and the cotton fiber are subjected to cross-linking reaction, the hydrophilic group hydroxyl in the cotton fiber is replaced by the hydrophobic group, so that the cotton fiber has affinity to the disperse dye, and can be dyed by using a conventional disperse dye dyeing method.

Detailed Description

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

The disperse dye dyeing method for treating the cotton fabric by the polyurethane comprises the following steps of:

(1) non-ironing pretreatment: the method comprises the following steps of (1) carrying out non-ironing finishing on cotton fabrics by using waterborne polyurethane as a non-ironing finishing agent, wherein the number average molecular weight of the waterborne polyurethane is 3000-50000;

(2) dyeing with a disperse dye: and (3) dyeing the cotton fabric pretreated in the step (1) by using a disperse dye preparation through a disperse dye.

In step (1), preferably, the process of permanent press finishing comprises: soaking the cotton fabric in finishing liquid containing waterborne polyurethane at two times and rolling the cotton fabric at two times to ensure that the liquid carrying rate is 70-80%, drying the cotton fabric for 3-10 minutes at 75-85 ℃, baking the cotton fabric for 1.5-3 minutes at 150-170 ℃, and then taking out the treated cotton fabric to carry out water washing and drying at 75-85 ℃.

The finishing liquid containing the aqueous polyurethane preferably further contains a penetrant and an auxiliary agent. Wherein the concentration of the waterborne polyurethane can be 50-100g/L, preferably 60-80 g/L; the concentration of the penetrant can be 0.1-2g/L, preferably 0.2-1 g/L; the concentration of the auxiliary agent is 10-40g/L, preferably 20-30 g/L.

In the invention, the auxiliary agent can catalyze the reaction of the aqueous polyurethane and the hydroxyl on the cotton fiber. In a specific embodiment, the adjuvant is at least one of tetraisobutyl titanate, zinc naphthenate, and iron octoate.

In the present invention, the penetrant may be a conventionally used penetrant in the art, and may be, for example, a commercially available penetrant NR.

In the present invention, the aqueous polyurethane may be a commercially available aqueous polyurethane product such as PU-3541 aqueous polyurethane available from Guangzhou Hunyzing New Material Co.

In a specific embodiment, the number average molecular weight of the aqueous polyurethane is preferably 5000-. Herein, the number average molecular weight is determined using gel chromatography (GPC).

In the method of the present invention, the disperse dye dyeing in the step (2) may be performed by using a disperse dye dyeing process which is conventional in the art, as follows, a preferred disperse dye dyeing step in the present invention: adding the cotton fabric into a disperse dye preparation, wherein the bath ratio is 1:10-50, the initial dyeing temperature is 30-60 ℃, then heating up at the heating rate of 1-3 ℃/min, keeping the temperature and dyeing for 40-80min after the temperature reaches 70-100 ℃, then cooling down at the cooling rate of 1-3 ℃/min, taking out the fabric after the temperature is reduced to below 50 ℃, and reducing and cleaning.

In the dyeing operation, disperse dye dyeing is carried out on the cotton fabric by using a dip dyeing method, the cotton fabric is dipped in dyeing liquid, the dyeing liquid is heated at a certain speed to increase the temperature so as to control the dyeing uniformity and the dyeing quality, heat preservation dyeing is carried out after the dyeing liquid reaches a proper temperature, a certain temperature is given to a dyeing system, so that the gaps among cotton fiber molecules are increased, the dye molecules can enter the modified cotton fiber molecules more conveniently and can be filled, dyeing is realized, and the cotton fabric is cooled and reduced and cleaned after dyeing is finished.

In the present invention, the disperse dye formulation is a disperse suspension of disperse dye in water, and the amount of the disperse dye can be 0.5% -5% of the amount of cotton fabric, for example, can be 1%, 2%, 3% or 4%.

In the present invention, the disperse dye is not particularly limited, and disperse dyes that are conventional in the art can dye cotton fabrics according to the scheme of the present invention, for example, the disperse dye may be at least one of disperse blue, disperse black, disperse gray, disperse red, disperse violet, disperse yellow and disperse orange. According to the actual process requirements, disperse dye coloring agents with various dyeing effects are prepared.

In a preferred embodiment of the present invention, a leveling agent is also included in the disperse dye formulation; the amount of the leveling agent can be 0.05-0.5%, preferably 0.1-0.4%, and more preferably 0.15-0.3% of the mass of the disperse dye formulation. The dye is promoted to be uniformly dyed by adding a small amount of leveling agent.

After the disperse dye in the step (2) of the invention is used for dyeing, because the disperse dye can not be completely ensured to completely enter the cotton fiber during dyeing, and some disperse dye can be attached to the surface of the fiber, and the poor dyeing fastness can be caused without removing the loose color, reduction cleaning is needed, and the dye molecules which do not enter the cotton fiber are damaged by using a strong reducing agent, so that the color fastness is improved, and the chromatic light is improved.

In the invention, the solution used for reduction cleaning can be a mixed aqueous solution of sodium hydrosulfite and caustic soda;

further, the concentration of sodium hydrosulfite in the solution for reduction cleaning is 0.5-4g/L, preferably 1-3 g/L;

further, the concentration of caustic soda in the solution for reduction cleaning is 0.5-4g/L, preferably 1-3 g/L.

In the present invention, the conditions of the reductive cleaning include: the bath ratio may be 1:10-30 (e.g., may be 1:10, 1:15, 1:20, 1:25 or 1:30), the temperature may be 70-100 ℃ (e.g., may be 70 ℃, 80 ℃, 90 ℃ or 100 ℃), and the time may be 5-30min (e.g., may be 5min, 10min, 15min, 20min, 25min or 30 min).

The present invention will be described in detail below by way of examples, but the scope of the present invention is not limited thereto.