阅读说明：本技术 改性再生纤维素纤维、用其加工的针织布及染色工艺 (Modified regenerated cellulose fiber, knitted fabric processed by using same and dyeing process ) 是由 潘华敏 于 2020-06-11 设计创作，主要内容包括：本发明涉及纺织加工的技术领域,尤其是涉及改性再生纤维素纤维、用其加工的针织布及染色工艺,改性再生纤维素纤维以浆粑为原料,通过如下步骤加工得到：碱纤维素的制备：以浆粑为原料,依次经浸渍、压榨及粉碎后得到碱纤维素；粘胶的制备：对碱纤维素依次进行老化与磺化处理,得到纤维素磺酸酯；将前述纤维素磺酸酯溶解在质量浓度为4%的NaOH溶液中,加入占浆粑5-8%的强力活化剂和占浆粑3-5%的阳离子改性剂,搅拌混合,得到粘胶；改性再生纤维素纤维的制备：将上述粘胶依次经过纤维成型与后处理操作,得到改性再生纤维素纤维；用该改性再生纤维素纤维织成的针织布,在无碱、无盐条件下染色后的色牢度优于传统改性织物的色牢度。(The invention relates to the technical field of textile processing, in particular to modified regenerated cellulose fibers, knitted fabrics processed by the modified regenerated cellulose fibers and a dyeing process, wherein the modified regenerated cellulose fibers are prepared by taking pulp as a raw material and processing the pulp through the following steps: preparing alkali cellulose: taking the pulp as a raw material, and sequentially carrying out impregnation, squeezing and crushing to obtain alkali cellulose; preparing viscose: sequentially aging and sulfonating the alkali cellulose to obtain cellulose sulfonate; dissolving the cellulose sulfonate into a NaOH solution with the mass concentration of 4%, adding a strong activating agent accounting for 5-8% of the pulp and a cationic modifier accounting for 3-5% of the pulp, and stirring and mixing to obtain viscose; preparing modified regenerated cellulose fibers: sequentially carrying out fiber forming and post-treatment operations on the viscose to obtain modified regenerated cellulose fibers; the color fastness of knitted fabrics woven by the modified regenerated cellulose fibers is superior to that of the traditional modified fabrics after the knitted fabrics are dyed under alkali-free and salt-free conditions.)

1. The modified regenerated cellulose fiber is characterized by being prepared from pulp cake serving as a raw material through the following steps:

preparing alkali cellulose: taking the pulp as a raw material, and sequentially carrying out impregnation, squeezing and crushing to obtain alkali cellulose;

preparing viscose: sequentially aging and sulfonating the alkali cellulose to obtain cellulose sulfonate; dissolving the cellulose sulfonate into a NaOH solution with the mass concentration of 4%, adding a strong activating agent accounting for 5-8% of the pulp and a cationic modifier accounting for 3-5% of the pulp, and stirring and mixing to obtain viscose;

preparing modified regenerated cellulose fibers: and (3) sequentially carrying out fiber forming and post-treatment operations on the viscose to obtain the modified regenerated cellulose fiber.

2. The modified regenerated cellulose fiber according to claim 1, characterized in that: the strong activating agent is prepared by mixing the following raw materials in percentage by weight: 5-10% of non-ionic penetrating agent, 3-5% of pH stabilizer, 7-13% of ammonium salt cationic surfactant and water which are complemented to 100%.

3. The modified regenerated cellulose fiber according to claim 2, characterized in that: the non-ionic penetrating agent is selected from one or more of fatty alcohol-polyoxyethylene ether, polyoxyethylene sorbitan monostearate and nonylphenol polyoxyethylene ether.

4. The modified regenerated cellulose fiber according to claim 2, characterized in that: the ammonium salt cationic surfactant is a double-active tertiary ammonium salt compound and/or a quaternary ammonium salt compound.

5. The modified regenerated cellulose fiber according to claim 1, characterized in that: the slurry cake has a polymerization degree of 500-800, a methyl cellulose content of more than or equal to 92.0 percent and a water content of less than or equal to 10 percent.

6. The modified regenerated cellulose fiber according to claim 1, characterized in that: the cellulose sulfonate had a degree of esterification of 50.

7. A knitted fabric, characterized in that: which is processed using the modified regenerated cellulose fiber of any one of claims 1-6.

8. A dyeing process for knitted fabrics according to claim 7, characterized in that it comprises the following operative steps:

dyeing pretreatment: adding 45-55g/L of hydrogen peroxide with the mass concentration of 30%, 25-35g/L of cold pad batch and 13-18g/L of cation modified protective agent, and performing cold pad batch treatment for more than 12 h;

dyeing: controlling the bath ratio to be 1:10, adding the reactive dye into water at 40 ℃ within 30 +/-1 min, and keeping the temperature for 10 +/-1 min; heating to 98 + -2 deg.C at a rate of 1.5 deg.C/min, and maintaining for 40 + -1 min;

hot washing: cooling to 80 + -2 deg.C, and hot washing for 20 + -1 min;

and (4) dehydrating, finishing and shaping in sequence to obtain the dyed knitted fabric.

9. Dyeing process for knitted fabrics according to claim 8, characterized in that: the cation modified protective agent is prepared by mixing the following raw materials in percentage by weight: 5-10% of non-ionic penetrant, 10-15% of hydrogen peroxide stabilizer, 10-20% of degreaser, 15-25% of chelating dispersant and water, wherein the balance is up to 100%.

10. Dyeing process for knitted fabrics according to claim 9, characterized in that: the deoiling agent is isomeric fatty dodecyl alcohol polyoxyethylene ether, and the chelating dispersant is maleic acid-acrylic acid copolymer.

Technical Field

The invention relates to the technical field of textile processing, in particular to a modified regenerated cellulose fiber, knitted fabric processed by the modified regenerated cellulose fiber and a dyeing process.

Background

The regenerated cellulose fiber is used as a textile raw material, and is obtained by taking natural cellulose such as wood, bamboo, hemp, cotton linter, reed, straw and the like as raw materials and carrying out a series of processes such as cooking, acid treatment, bleaching and the like; the raw materials are resources which can be continuously regenerated and continuously utilized in nature, and the resources are widely distributed, easily obtained and suitable for being developed and utilized persistently.

At present, a lot of knitted fabrics processed by regenerated cellulose fibers appear, the structural composition of the knitted fabrics is similar to that of cotton, the difference is that the moisture absorption and the air permeability of the knitted fabrics are better than those of cotton fibers, so that the knitted fabrics are the best ones in the moisture absorption and the air permeability of all chemical fibers and are known as 'breathable fabrics'. Meanwhile, the silk fabric has partial advantages of silk which cotton fibers do not have, the dyeing beauty is superior to that of the cotton fibers, the hand feeling is soft, plump and smooth, the drapability and the silk-like luster are excellent, and the silk fabric is suitable for making underwear, outer garments and various decorative articles.

The same as the cloth woven by cotton fiber, the cloth woven by regenerated cellulose fiber needs to be subjected to dyeing process to obtain the cloth with different colors, so as to meet the requirements of different products. It is known that cellulose fibres, when they are brought into contact with the dyeing bath, generally carry a certain amount of charge on their surface; under neutral or alkaline conditions, the surface of the cellulose fibers is generally negatively charged. However, most dyes used to dye cellulosic fibers, such as reactive dyes, direct dyes, vat dye leuco dyes, and the like, are also negatively charged in the dye bath. Due to the electrostatic repulsion between the dye and the cellulose fiber, the dye uptake is hindered, resulting in low dye uptake and poor color fastness.

In order to solve the dyeing problem, in the traditional process, a cationic modifier is mostly adopted to modify the fabric to obtain a modified fabric, and then the modified fabric is dyed. Because the micromolecular cationic modifier has poor thermal stability and is easy to hydrolyze, the traditional modified fabric is modified by adopting a macromolecule cationic modifier. However, the polymeric cationic modifier has poor permeability and is difficult to penetrate into the fibers, and cations are mainly present in the surface layer of the fabric after modification. Because the surface layer of the fabric fiber has rich cations during dyeing, the dyeing speed is high, the surface layer of the fabric fiber has more dyes and the dye in the fiber is less, so that the phenomena of dyeing patterns, ring dyeing, color deposition and the like occur, and the color fastness is poor.

In addition, in order to remove oil and stains generated on the surface of the modified fabric in the spinning and weaving processes and the accompanying matters on the fiber before dyeing so as to avoid the influence on cloth surface dyeing, the modified fabric is subjected to pretreatment operation before dyeing. The traditional pretreatment operation specifically adopts the following process: adopting an immersion mode, controlling the bath ratio to be 1:10, adding hydrogen peroxide with the mass concentration of 30 percent and accounting for 5 percent of the total weight of the fabric, caustic soda with the weight of 2 percent of the total weight of the fabric, a refining agent with the weight of 1 percent of the total weight of the fabric and a deoiling agent with the weight of 1 percent of the total weight of the fabric into a cylinder, and preserving heat for 40min at 98 ℃; washing with water for 3 times. Although the traditional pretreatment process can remove the oil stains on the surface of the modified fabric and reduce the influence of the oil stains on dyeing, the traditional pretreatment process has the following defects: firstly, in the treatment process, in a high-temperature alkaline environment at 98 ℃, the cations existing on the surface of the modified fabric can be interfered and damaged, so that the color fastness of the later dyeing of the modified fabric is reduced; secondly, repeated washing is needed for 3 times, and the water consumption is large; high-temperature water with the temperature of 98 ℃ is needed, the power consumption is large, the steam loss is large, and the energy consumption is high.

Disclosure of Invention

Aiming at the defects in the prior art, the first object of the invention is to provide modified regenerated cellulose fibers, which are obtained by modification treatment in the process of preparing the regenerated cellulose fibers from pulp, and the color fastness of fabrics woven from the modified regenerated cellulose fibers is superior to that of traditional modified fabrics.

The first object of the present invention is achieved by the following technical solutions:

the modified regenerated cellulose fiber is prepared by taking pulp cake as a raw material through the following steps:

preparing alkali cellulose: taking the pulp as a raw material, and sequentially carrying out impregnation, squeezing and crushing to obtain alkali cellulose;

preparing viscose: sequentially aging and sulfonating the alkali cellulose to obtain cellulose sulfonate; dissolving the cellulose sulfonate into a NaOH solution with the mass concentration of 4%, adding a strong activating agent accounting for 5-8% of the pulp and a cationic modifier accounting for 3-5% of the pulp, and stirring and mixing to obtain viscose;

preparing modified regenerated cellulose fibers: and (3) sequentially carrying out fiber forming and post-treatment operations on the viscose to obtain the modified regenerated cellulose fiber.

By adopting the technical scheme, in the process of preparing the regenerated cellulose fiber from the pulp cake, the modified regenerated cellulose fiber is obtained by modifying with a strong activating agent and a cationic modifying agent, the self property of the modified regenerated cellulose fiber is improved, and a fabric woven by the modified regenerated cellulose fiber has excellent performances of good permeability and level-dyeing property and good color fastness.

Preferably, the method comprises the following steps: the strong activating agent is prepared by mixing the following raw materials in percentage by weight: 5-10% of non-ionic penetrating agent, 3-5% of pH stabilizer, 7-13% of ammonium salt cationic surfactant and water which are complemented to 100%.

By adopting the technical scheme, the nonionic penetrant is mainly used for improving the permeability of the regenerated cellulose fiber, so that the internal and external modification of the regenerated cellulose fiber is uniform. Due to the consumption of OH in the modification process^-Ions and pH stabilizers will gradually release OH^-Ions, so as to stabilize the pH value of the solution at 10. The ammonium salt cationic surfactant belongs to weak cationic compounds, has a competitive dyeing effect with a cationic modifier, and is beneficial to improving the modification uniformity.

Preferably, the method comprises the following steps: the non-ionic penetrating agent is selected from one or more of fatty alcohol-polyoxyethylene ether, polyoxyethylene sorbitan monostearate and nonylphenol polyoxyethylene ether.

By adopting the technical scheme, the fatty alcohol-polyoxyethylene ether is also called polyoxyethylene fatty alcohol ether, called AEO for short, ether bonds in molecules are not easy to be damaged by acid and alkali, so the fatty alcohol-polyoxyethylene ether has the advantages of high stability, good water solubility, electrolyte resistance, easiness in biodegradation and small foam, and is widely applied to the textile printing and dyeing industry. Polyoxyethylene sorbitan monostearate, tween 60, lemon to orange liquid, for emulsifiers, stabilizers and defoamers. The polyoxyethylene nonyl phenyl ether has good penetrating, emulsifying, dispersing, acid-resisting, alkali-resisting, hard water-resisting, reduction-resisting and oxidation-resisting capabilities.

Preferably, the method comprises the following steps: the ammonium salt cationic surfactant is a double-active tertiary ammonium salt compound and/or a quaternary ammonium salt compound.

Preferably, the method comprises the following steps: the slurry cake has a polymerization degree of 500-800, a methyl cellulose content of more than or equal to 92.0 percent and a water content of less than or equal to 10 percent.

By adopting the technical scheme, the polymerization degree is too high, the viscosity of the alkali cellulose after oxidative degradation is higher, and the solubility of the cellulose sulfonate after sulfonation reaction is lower, so that the filtering performance of the viscose is influenced. Pulp cake with too low polymerization degree has the characteristics of hemicellulose, and the impregnation, sulfonation and filtration in a viscose process are influenced. The higher the content of alpha-fibers, the higher the viscose production rate, but the cost is increased, so the pulp cake with the content of the alpha-fibers of more than 92.0 percent is selected by comprehensively considering the viscose production rate and the cost. The water in the pulp cake is internal water, and in the cellulose fiber production process, if the water content in the pulp cake is too high, the concentration of the dipping alkali liquor can be diluted, the dipping effect is influenced, and the viscose preparation rate and the quality of the finished regenerated cellulose fiber are reduced.

Preferably, the method comprises the following steps: the cellulose sulfonate had a degree of esterification of 50.

By adopting the technical scheme, the cellulose sulfonate with the esterification degree has better solubility in water and sodium hydroxide solution, and is favorable for being dissolved in the alkali liquor of the invention for modification treatment.

The second purpose of the present invention is to provide a knitted fabric, which is realized by the following technical scheme:

a knitted fabric processed from the modified regenerated cellulose fiber described above.

By adopting the technical scheme, the raw material fiber of the processed knitted fabric is modified, and the obtained modified regenerated cellulose fiber has uniform internal and external cation distribution. The method overcomes the problems of colored patterns, ring dyeing and color deposition caused by more dye on the surface layer of the fabric fiber and less dye in the fiber during dyeing because the fabric is directly modified in the traditional technology. The knitted fabric has good dyeing performance and high color fastness.

The third purpose of the invention is to provide a dyeing process of the knitted fabric, which has no salt, alkali or assistant in the dyeing process, is environment-friendly and has low pollution; the knitted fabric obtained by dyeing has excellent dyeing color fastness.

The third purpose of the invention is realized by the following technical scheme:

a dyeing process of knitted fabric comprises the following operation steps:

dyeing pretreatment: adding 45-55g/L of hydrogen peroxide with the mass concentration of 30%, 25-35g/L of cold pad batch and 13-18g/L of cation modified protective agent, and performing cold pad batch treatment for more than 12 h;

dyeing: controlling the bath ratio to be 1:10, adding the reactive dye into water at 40 ℃ within 30 +/-1 min, and keeping the temperature for 10 +/-1 min; heating to 98 + -2 deg.C at a rate of 1.5 deg.C/min, and maintaining for 40 + -1 min;

hot washing: cooling to 80 + -2 deg.C, and hot washing for 20 + -1 min;

and (4) dehydrating, finishing and shaping in sequence to obtain the dyed knitted fabric.

By adopting the technical scheme, the pretreatment mode of cold pad batch is adopted, natural reaction is carried out at room temperature, a large amount of water, electricity and steam are saved, and the energy consumption is reduced. In the cold pad batch treatment, a cold pad batch is added to play roles of wetting, emulsifying, permeating, refining and the like; the cation modified protective agent can protect cations on the knitted fabric, so that the dyeing effect is improved. In the dyeing process, auxiliaries such as sodium sulfate, inorganic salt and caustic soda are not required to be added, so that the energy is saved and the environment is protected.

Preferably, the method comprises the following steps: the cation modified protective agent is prepared by mixing the following raw materials in percentage by weight: 5-10% of non-ionic penetrant, 10-15% of hydrogen peroxide stabilizer, 10-20% of degreaser, 15-25% of chelating dispersant and water, wherein the balance is up to 100%.

By adopting the technical scheme, the non-ionic penetrant is mainly used for improving the permeability of the knitted fabric, so that the inside and the outside of the knitted fabric can be uniformly dyed. Stabilization of hydrogen peroxideThe agent is used for protecting hydrogen peroxide in dyeing pretreatment, and is beneficial to the hydrogen peroxide to play a role in removing impurity pigments. The deoiling agent mainly plays a role in removing oil stains on the surface of the knitted fabric. The chelating dispersant is a high-efficiency multipurpose organic chelate which can soften water and can be used for Ca²⁺、Mg²⁺、Fe³⁺The metal ions have strong chelating force, so that the generation of precipitates in the dyeing and finishing process is prevented, silicon scale, calcium soap precipitates and oligomers in equipment can be slowly dissolved and removed, the recontamination of metal salts on knitted fabrics is prevented, and the dyeing effect and the color fastness are improved.

Preferably, the method comprises the following steps: the deoiling agent is isomeric fatty dodecyl alcohol polyoxyethylene ether, and the chelating dispersant is maleic acid-acrylic acid copolymer.

By adopting the technical scheme, the isomeric fatty dodecyl alcohol polyoxyethylene ether belongs to isomeric alcohol ether, is a high-efficiency dispersing agent, wetting agent and emulsifying agent, and is an excellent substitute of alkylphenol polyoxyethylene ether in textile auxiliaries. Maleic Acid-acrylic Acid Copolymer (MA/AA) is prepared by copolymerizing Maleic Acid and acrylic Acid in a certain ratio.

In summary, the invention includes at least one of the following beneficial technical effects:

(1) the modified regenerated cellulose fiber is adopted to process knitted fabrics, and the knitted fabrics are dyed by matching with the dyeing process disclosed by the invention to obtain the dyed knitted fabrics, wherein the dry rubbing fastness of the dyed knitted fabrics is more than 4 grades and can reach 4-5 grades at most; the wet rubbing fastness reaches more than grade 3, and can reach grade 4 at most; the washing fastness reaches more than 3-4 grade, and can reach 4-5 grade at most;

(2) the knitted fabric obtained by the dyeing process has the advantages of consistent surface color depth, color light and bright brightness, no colored flower, ring dyeing and color deposition, better level dyeing property and permeability than the traditional process, and good dyeing effect;

(3) the invention realizes the dyeing of the knitted fabric under the conditions of no alkali, no salt and no auxiliary agent, and has the advantages of energy saving and environmental protection.

Detailed Description

The present invention will be described in further detail with reference to specific examples.

The following raw materials and auxiliaries are all commercially available products, and specifically comprise: the cation modifier is selected from a cation modifier FK-316; the pH stabilizer selects borax-sodium hydroxide buffer solution; the fatty alcohol-polyoxyethylene ether is Baschiff isomeric alcohol XP-50; the polyoxyethylene sorbitan monostearate is selected from Suzhou Yuitarun chemical industry Co., Ltd, and the effective content is more than or equal to 98%; the polyoxyethylene nonyl phenyl ether is selected from NP-10 series superior products of Jinan Jianhui chemical Limited company; selecting a cationization modifier CF-3 of Shanghai color weaving research institute from the double-active tertiary ammonium salt compound; selecting a cationization modifier CF-2 of Shanghai color weaving research institute as the quaternary ammonium salt compound; the cold pad batch selects TF-120L; the hydrogen peroxide stabilizer is selected from anionic organic compound XIAWA L-350 from Guangzhou Jeneng textile technology Co., Ltd; the deoiling agent is isomeric fatty dodecyl alcohol polyoxyethylene ether, and is basf isomeric alcohol XP-50; the chelating dispersant is maleic acid-acrylic acid copolymer selected from Shandong Tengwang chemical Co., Ltd, and has an effective substance content of 50%.

The invention is illustrated by taking the pulp cake processed by taking needle-leaved wood as a raw material, and the details are as follows.