Preparation and application of a splitting agent for lyocell pure and blended fabric

Abstract

The present application relates to the field of dyeing and finishing auxiliaries process, and discloses preparation and application of a fiber opening agent for lyocell pure spinning and blended fabric.The suede style of lyocell fiber is popular, but it is necessary to open the lyocell fiber under alkaline and high temperature environment by using strong mechanical force, which not only affects the performance and fastness of lyocell fiber, but also needs to be neutralized by acid after alkaline treatment, increasing the cost of fiber opening process.The preparation and application process of the fiber opening agent comprises the following steps: (1) preparation of the fiber opening agent; (2) application of the fiber opening agent.The present application has the following advantages: the fiber opening agent can open the lyocell pure spinning and blended fabric under neutral conditions, more easily reduces the damage to the strength of lyocell fiber, simplifies the subsequent acid neutralization process, shortens the process flow and time, and can alleviate the safety and cost problems brought by the traditional alkaline fiber opening method.

Description

TECHNICAL FIELD

[0001] The present application relates to the preparation and application of an opening agent for lyocell pure spinning and blended fabrics, belonging to the field of dyeing and finishing auxiliaries and processes. BACKGROUND

[0002] Lyocell fiber was introduced in the 1990s, which is a regenerated cellulose fiber made from natural materials such as bamboo and wood through spinning process, different from synthetic fibers such as polyester, natural and environmentally friendly and biodegradable, with many advantages of natural fibers and chemical fibers. Lyocell fiber has a hand close to real silk, delicate and smooth, light and comfortable, and is more suitable for people sensitive to skin touch; its surface is smooth and flat, with small air volume and high thermal conductivity, especially in hot summer, it will have obvious cooling and cooling feeling; the standard moisture regain of lyocell fiber is 13%, and its moisture absorption capacity is better than that of cotton fiber, with fast moisture absorption and sweat absorption effect; lyocell fiber is made from renewable resources such as bamboo and wood, which can alleviate the problem of resource shortage, and is safe and pollution-free in production process, and can be naturally degraded in the environment, in line with the current green and environmentally friendly life concept. Therefore, lyocell fiber is considered to be a new type of environmentally friendly material with great value.

[0003] Due to the easy fibrillation of lyocell fiber, the fabric made of lyocell fiber in peach skin style is very popular, but the degree of fibrillation is difficult to control, which leads to the decrease of the rubbing fastness of lyocell fiber, and restricts the wide use and promotion of lyocell fiber.

[0004] Patent No. CN114592364A discloses a low-energy pretreatment, dyeing and finishing method to improve the overall color fastness of lyocell fiber and stabilize the color of the fabric, while reducing the energy consumption of lyocell dyeing, aiming at the problems of poor color fastness of lyocell fiber, color difference caused by sand washing process and high energy consumption of process. The wet rubbing fastness improver TF-239A developed can alleviate the problem of poor rubbing fastness of lyocell fiber caused by alkaline fibrillation. However, alkaline fibrillation is still the main method for fibrillation of lyocell fiber, and the problem of complex process caused by alkaline fibrillation has not been substantially solved.

[0005] Patent No. CN113151955A discloses that after lyocell filament is finished and woven into gray cloth, it is subjected to flat relaxation desizing, airflow fibrillation, enzyme treatment, airflow dyeing, opening, tentering, mechanical softening and preshrinking to obtain the product, which can reduce or even eliminate the problems of fabric creases, scratches and uneven peach skin caused by traditional sand washing, and improve the fabric yield, but the treatment of lyocell fiber in the pretreatment process is only suitable for lyocell pure spinning fiber, which limits the blending use of lyocell fiber with other fibers.

[0006] The suede style of lyocell fibers is popular, but if the lyocell fibers are fibrillated under the action of alkali, high temperature and mechanical force, not only the degree of fiber strength cannot be controlled, but also the subsequent dyeing and finishing process and various performance fastness of lyocell fibers are affected; in addition, after the treatment under high temperature and alkali, acid neutralization is still needed, which not only increases the pretreatment process, but also easily causes high production cost, therefore, developing an opening agent for lyocell pure spinning and blended fabric has important significance for dyeing and finishing auxiliaries and process field. SUMMARY

[0007] The purpose of the present application is to provide a preparation and application of an opening agent for lyocell pure spinning and blended fabric, which can fibrillate the lyocell pure spinning and blended fabric in a neutral or weak alkaline environment, alleviate the strength damage caused by the traditional alkaline fibrillation process, and further, no acid neutralization is needed after the fibrillation process, thereby reducing the production cost.

[0008] To achieve the above purpose, the preparation and application of an opening agent for lyocell pure spinning and blended fabric provided by the present application adopts the following technical scheme:

[0009] (1) 4-hydroxy-2-butenoic acid, potassium persulfate, sodium hydroxide and other raw materials are used to synthesize the opening agent;

[0010] (2) Application of the opening agent: the opening agent is used to fibrillate the lyocell pure spinning and blended fabric;

[0011] (3) Reactive dyeing of the lyocell component of pure spinning and blended fabric;

[0012] (4) Softening.

[0013] Further, the synthesis method of the opening agent in step (1) is as follows: 35-45 parts of 4-hydroxy-2-butenoic acid and 100 parts of water are slowly added into a reaction container equipped with a condensation reflux device, stirring is started, and the temperature of the reaction mixture is controlled at 70-80 ℃; 0.7-1.2 parts of potassium persulfate is dissolved in 10-20 parts of water and slowly added into the reaction container, after 1-1.5 h of dropping, the temperature is kept at 70-80 ℃ for 1.5-2 h during the dropping and keeping processes; after the reaction is completed, the cooling system is started, the temperature of the reaction system is reduced to 40-50 ℃, and then 95-105 parts of 15% sodium hydroxide aqueous solution is added into the reaction container, the pH of the reaction mixture is controlled at 7-9 and the temperature of the reaction mixture is controlled below 50 ℃ during the dropping process, after the dropping is completed, the stirring is continued for 10-15 min, and the opening agent for lyocell pure spinning and blended fabric is prepared.

[0014] The specific reaction formula of the synthesis of the opening agent is as follows:

[0015]

[0016] Further, the application of the opening agent in step (2) is as follows: the fabric is placed in a dyeing vat, the self-made opening agent is used in an amount of 10-20 g / L, the bath ratio is 1:10-15, the temperature is raised to 90-95 DEG C at a rate of 2 DEG C / min, the temperature is kept for 50-70 min, the opening is finished, the temperature is lowered to 60 DEG C at a rate of 2 DEG C / min, and the liquid is discharged without washing, and then the fabric is dyed with reactive dyes.

[0017] Further, the reactive dyeing of the lyocell pure and blended fabric in step (3) is as follows: a reactive dyeing solution is prepared, the amount of the reactive dye is 1-3% (o.w.f), the bath ratio is 1:20, the amount of sodium carbonate is 15-20 g / L, and the amount of sodium sulfate is 30-70 g / L; the fabric is dyed at 30 DEG C, 1 / 2 of the sodium sulfate is added after 10 min, the remaining 1 / 2 of the sodium sulfate is added after another 10 min, and the fabric is kept for 15 min, the temperature is raised to 60 DEG C at a rate of 1 DEG C / min, 1 / 10 of the sodium carbonate is added, the remaining 9 / 10 of the sodium carbonate is added after 10 min, the temperature is kept for 40 min, and then the temperature is lowered to room temperature at a rate of 1.5 DEG C / min.

[0018] Further, the soaping of the fabric after the reactive dyeing in step (3) is as follows: the dyeing is washed to remove the floating color, the color of the fabric is ensured, and the color fastness of the fabric is enhanced; the amount of the soap is 3 g / L, the bath ratio is 1:50, and the soaping is carried out at 95 DEG C for 10-15 min.

[0019] Further, the softening of the fabric in step (4) is as follows: the fabric is treated with the softening agent by two-dip-two-nip, the setting temperature is 170-175 DEG C, and the setting time is 45-55 s.

[0020] The application has the following advantages:

[0021] (1) The self-made neutral opening agent for lyocell pure and blended fabric is used to replace the traditional alkali opening agent such as sodium hydroxide, the opening effect is sufficient to achieve the effect of alkali opening, the strength loss of the fabric is reduced, the opening degree of the fabric is controlled, and the short-felt lyocell pure and blended fabric has no obvious difference with the fine felt lyocell pure and blended fabric obtained by the alkali opening method.

[0022] (2) The prepared opening agent can be used in a neutral or weak alkaline environment for opening, and subsequent neutralization is not required, thereby simplifying the production process, reducing the production cost, and achieving high economic benefits. DETAILED DESCRIPTION

[0023] The technical solutions of the present application are further described below through specific examples. It should be understood that the implementation of the present application is not limited to the following examples, and any form of variation and / or change made to the present application will fall within the scope of protection of the present application. In the present application, unless specified, all parts and percentages are by weight, and the equipment and raw materials used can be purchased from the market or are commonly used in the art. The methods in the following examples are conventional methods in the art, unless otherwise specified.

[0024] The fabric used in the present application is lyocell pure fabric, lyocell / polyester bird's eye double-sided knitted fabric.

[0025] Example 1: 35 g of 4-hydroxy-2-butenoic acid and 100 g of water were slowly added to a reaction vessel equipped with a condensation reflux device, stirring was started, and the temperature of the reaction mixture was controlled at 70℃; 0.7 g of potassium persulfate was dissolved in 10 g of water and slowly added to the reaction vessel, after 1 h of dripping, the temperature was kept at 70℃ for 1 h, and the temperature in the reaction system was controlled during the dripping and incubation process; after the reaction was completed, the cooling system was started, the temperature of the reaction system was reduced to 40℃, and then 95 g of a 15% sodium hydroxide aqueous solution was added to the reaction vessel, the pH of the reaction mixture was controlled at 7-9, and the temperature of the reaction mixture was controlled below 50℃ during the dripping process, after the dripping was completed, the stirring was continued for 10 min, and the opening agent for lyocell pure fabric and blended fabric was prepared.

[0026] Example 2: 40 g of 4-hydroxy-2-butenoic acid and 100 g of water were slowly added to a reaction vessel equipped with a condensation reflux device, stirring was started, and the temperature of the reaction mixture was controlled at 75℃; 1.0 g of potassium persulfate was dissolved in 15 g of water and slowly added to the reaction vessel, after 1 h of dripping, the temperature was kept at 75℃ for 1.5 h, and the temperature in the reaction system was controlled during the dripping and incubation process; after the reaction was completed, the cooling system was started, the temperature of the reaction system was reduced to 45℃, and then 100 g of a 15% sodium hydroxide aqueous solution was added to the reaction vessel, the pH of the reaction mixture was controlled at 7-9, and the temperature of the reaction mixture was controlled below 50℃ during the dripping process, after the dripping was completed, the stirring was continued for 12 min, and the opening agent for lyocell pure fabric and blended fabric was prepared.

[0027] Example 3: 45 g of 4-hydroxy-2-butenoic acid and 100 g of water were slowly added to a reaction vessel equipped with a condensation reflux device, stirring was started, and the temperature of the reaction mixture was controlled at 80℃; 1.2 g of potassium persulfate was dissolved in 20 g of water and slowly added to the reaction vessel, and after 1.5 h of dripping, the temperature was maintained at 80℃ for 2 h. During the dripping and maintaining process, the temperature in the reaction system was controlled at 80℃; after the reaction was completed, the cooling system was started, and the temperature of the reaction system was reduced to 50℃; then 100 g of a 15% sodium hydroxide aqueous solution was added to the reaction vessel, and the pH of the reaction mixture was controlled at 7-9 and the temperature of the reaction mixture was controlled below 50℃ during the dripping process; after the dripping was completed, the stirring was continued for 15 min, and a fiber-opening agent for lyocell pure spinning and blended fabric was prepared.

[0028] Application of the fiber-opening agent in lyocell pure spinning and blended fabric:

[0029] 1. Lyocell pure fabric

[0030] The fabric was placed in a dyeing vat, a fiber-opening working solution was prepared, the amount of fiber-opening agent was 10 g / L, the bath ratio was 1:12, the temperature was increased to 90℃ at a rate of 2℃ / min, and the temperature was maintained at 90℃ for 60 min. After the fiber-opening was completed, the temperature was decreased to 60℃ at a rate of 2℃ / min, and the liquid was discharged. Without washing, the fabric was dyed with reactive dyes.

[0031] A reactive dye working solution was prepared, the amount of reactive dye was 2% (o.w.f), the bath ratio was 1:20, the amount of sodium carbonate was 15 g / L, and the amount of sodium sulfate was 40 g / L. The dyeing was started at 30℃, 1 / 2 of the sodium sulfate was added after 10 min of dyeing, the remaining 1 / 2 of the sodium sulfate was added after another 10 min of dyeing, and the dyeing was continued for 15 min, which played a role in promoting the dyeing; then the temperature was increased to 60℃ at a rate of 1℃ / min, 1 / 10 of the sodium carbonate was added, the temperature was maintained for 10 min, the remaining 9 / 10 of the sodium carbonate was added, and the temperature was maintained at 60℃ for 40 min, which played a role in fixing the color; then the temperature was decreased to room temperature at a rate of 1.5℃ / min, and the fabric was subjected to a post-soaping process, the amount of soap was 3 g / L, the bath ratio was 1:50, and the soaping was carried out at 95℃ for 10-15 min, and then the fabric was washed with cold water.

[0032] A soft finishing agent was used for two-dipping and two-padding treatment of the lyocell pure fabric, the setting temperature was 170℃, and the setting time was 45 s, and the finished product was obtained.

[0033] 2. Lyocell / polyester bird's eye double-sided knitted fabric

[0034] Disperse dye working solution was prepared, the amount of disperse dye was 2% (o.w.f), bath ratio was 1:20, the pH value of working solution was 4.8, the fabric was placed in the dyeing vat, and was dyed at room temperature, the temperature was raised to 90 ℃ at a rate of 2 ℃ / min, then was raised to 130 ℃ at a rate of 1 ℃ / min, and was kept for 60 min, after dyeing, the temperature was reduced to 80 ℃ at a rate of 2 ℃ / min, and then alkaline reduction cleaning was carried out, and the fabric was washed with cold water.

[0035] The fabric was placed in the dyeing vat, and fibrillation working solution was prepared, the amount of fibrillation agent was 15 g / L, and the bath ratio was 1:12, the temperature was raised to 90 ℃ at a rate of 2 ℃ / min, and was kept for 60 min, after fibrillation, the temperature was reduced to 60 ℃ at a rate of 2 ℃ / min, and the liquid was discharged, and the fabric was dyed with reactive dyes without washing.

[0036] Reactive dye working solution was prepared, the amount of reactive dye was 2% (o.w.f), the bath ratio was 1:20, the amount of sodium carbonate was 15 g / L, and the amount of sodium sulfate was 40 g / L, the fabric was dyed at 30 ℃, 1 / 2 sodium sulfate was added after dyeing for 10 min, the remaining 1 / 2 sodium sulfate was added after dyeing for another 10 min, and the fabric was kept for 15 min, which played a role in promoting dyeing, then the temperature was raised to 60 ℃ at a rate of 1 ℃ / min, 1 / 10 sodium carbonate was added, the fabric was kept for 10 min, and then the remaining 9 / 10 sodium carbonate was added, the fabric was kept for 40 min at the temperature, which played a role in fixing color, then the temperature was reduced to room temperature at a rate of 1.5 ℃ / min, and the fabric was subjected to the subsequent soaping, the amount of soap was 3 g / L, the bath ratio was 1:50, and the fabric was soaped at 95 ℃ for 10-15 min, and then the fabric was washed with cold water.

[0037] The lyocell blended fabric was subjected to two-dip-two-nip treatment with soft finishing agent, the setting temperature was 175 ℃, and the setting time was 50 s, and the finished product was prepared.

[0038] Fibrillation agent application evaluation index:

[0039] 1. Fibrillation rate evaluation

[0040] The total number of fibers and the number of split fibers were observed longitudinally on an electron microscope, and the fibrillation rate S = N / N0*100% was calculated according to the formula, wherein N represents the number of split fibers, and N0 represents the total number of fibers. The fibrillation rates of the fabrics after fibrillation with the fibrillation agent and liquid alkali (mass fraction of 32%) were compared.

[0041] 2. Color light evaluation

[0042] The colorimetric colorimeter DateColor SF600X was used to test the dyed lyocell pure or blended fabric. Eight points were selected from each sample, and the average value was obtained after three measurements. The effects of the opening agent process and the sodium hydroxide (32% by mass) opening process on the color of the fabric were compared.

[0043] 3. Hand feeling evaluation

[0044] The short pile feeling of the fabric treated by the two different opening processes was evaluated by touching the fabric with multiple hands. The hand feeling evaluation was graded from 1 to 3.

[0045] Grade 1: unqualified. The opening is insufficient or excessive, the short pile feeling is poor, and the customer is not satisfied.

[0046] Grade 2: qualified. The opening is normal, the hand feeling is slightly hard or soft, and the short pile feeling meets the customer's demand.

[0047] Grade 3: excellent. The short pile feeling is strong, the hand feeling is smooth, and the customer's demand is met.

[0048] Application evaluation results of the opening agent:

[0049] Table 1: Opening effect of the opening agent

[0050]

[0051] As shown in the table, the opening rate, the color of the dyed fabric, and the hand feeling of the lyocell pure or blended fabric treated by the opening agent of Examples 1, 2, and 3 are similar to those treated by the sodium hydroxide (32% by mass) opening process. This indicates that the opening agent of Examples 1, 2, and 3 can simplify the subsequent acid neutralization process, shorten the process flow and time, and alleviate the safety and cost problems caused by the traditional alkaline opening method.

[0052] The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts of each embodiment can be referred to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method part.

[0053] The above describes the method and device provided by the present application

[0054] The principle and implementation manner of the present application are described by using specific examples in the present application. The above examples are only used for helping to understand the method of the present application and its core idea. It should be pointed out that, for the ordinary skilled in the art, some improvements and modifications can be made to the present application without departing from the principle of the present application, and these improvements and modifications fall within the protection scope of the present application.

Claims

1. A process for the preparation of a splitting agent for lyocell pure and blended fabrics, characterized in that The 4-hydroxy-2-butenoic acid, potassium persulfate, sodium hydroxide and water are used as raw materials to prepare the opening agent.

2. The preparation method of the opening agent according to claim 1, wherein the preparation process is as follows: 35-45 parts of 4-hydroxy-2-butenoic acid and 100 parts of water are slowly added into a reaction container with a condensation reflux device, respectively, stirring is started, and the temperature of the reaction mixture is controlled at 70-80 DEG C; 0.7-1.2 parts of potassium persulfate is dissolved in 10-20 parts of water and slowly added into the reaction container, after 1-1.5 hours of dropping, the reaction system is kept at the temperature for 1.5-2 hours, and the temperature of the reaction system is controlled at 70-80 DEG C during the dropping and keeping; after the reaction is completed, a cooling system is started, the temperature of the reaction system is decreased to 40-50 DEG C, and 95-105 parts of 15% sodium hydroxide aqueous solution is added into the reaction container, the pH of the reaction mixture is controlled at 7-9 and the temperature of the reaction mixture is controlled below 50 DEG C during the dropping, after the dropping is completed, the stirring is continued for 10-15 minutes, and the opening agent for lyocell pure spinning and blended fabric is prepared.

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