CN110144658B

CN110144658B - Production method of composite yarn with effect of colored gray

Info

Publication number: CN110144658B
Application number: CN201910501118.5A
Authority: CN
Inventors: 宋辉辉; 李景川; 赵尚振; 李苏
Original assignee: Anta China Co Ltd
Current assignee: Anta China Co Ltd
Priority date: 2019-06-11
Filing date: 2019-06-11
Publication date: 2021-01-29
Anticipated expiration: 2039-06-11
Also published as: CN110144658A

Abstract

The invention provides a production method of composite yarn with a graying effect, which comprises the following steps: s1, opening and picking the short staple of raw cotton to make cotton bundles; mixing a dye, polyacrylonitrile and a solvent to obtain a mixed spinning solution; s2, carding the cotton bundles obtained in the step S1, and in the process of forming a primary color cotton web by carding cotton, performing electrostatic spinning on the mixed spinning solution to compound the formed colored nanofibers and the primary color cotton web to prepare a composite cotton sliver; s3, the composite cotton sliver obtained in the step S2 is subjected to combing, drawing, roving and spinning in sequence to obtain the composite yarn with the effect of flower ash. In the cotton spinning and carding process, colored polyacrylonitrile nanofibers produced by electrostatic spinning are directly mixed into a primary-color cotton web, and finally, the composite yarn with a special effect of cotton ash can be produced through a spinning process. The mixing process in the production is simpler and more efficient, the process flow is greatly shortened, and the cost is reduced.

Description

Production method of composite yarn with effect of colored gray

Technical Field

The invention relates to the technical field of colored gray yarns, in particular to a production method of a composite yarn with a colored gray effect.

Background

The natural color yarn and the dyed yarn are two types of conventional yarns, and the dyed yarn is generally dyed into a required color on a dyeing machine in a cheese or hank mode. The blended yarn is a novel yarn which is newly developed, and is a yarn which is formed by blending natural fibers and chemical fibers which are dyed into different colors and have different properties, and special colors and service performances which are not possessed by the natural yarn and the dyed natural yarn can be obtained through color blending. In a broad sense, a gray yarn, i.e., a single-color mixed yarn, refers to a yarn obtained by blending a fiber dyed in a single color with a natural-color fiber. The 'colored gray yarn' in the narrow sense is formed by blending black dyed fibers and natural color fibers, is one of the most common mixed color yarns at present, is intuitively called as the colored gray yarn because the appearance color of the colored gray yarn is similar to the burnt cigarette ash, and is also commonly called as the 'ash yarn'.

The color and properties of gray yarn are generally intermediate between that of grey yarn and dyed yarn; the colored gray yarn is made of all cotton or pure cotton yarn, polyester cotton yarn and the like. The fabric with the effect of the colored gray is woven by the colored gray yarn, is different from the traditional plain fabric, colored woven fabric and printed fabric, has unique color and style effects, and is popular with consumers.

At present, the production method of the pure cotton gray yarn and the gray fabric which are most widely applied comprises the following steps: firstly dyeing cotton fiber, mixing the colored loose fiber and original fiber according to a certain proportion, then carrying out cotton carding, drawing, roving, spinning and other spinning processes to form pure cotton gray yarn, and finally weaving to obtain the pure cotton fabric with the gray effect. In the production process of the traditional pure cotton gray yarn, the procedures of dyeing, washing, drying and the like are needed to be carried out on the dispersed fibers, so that the production period of the whole gray yarn is at least doubled compared with that of the conventional yarn, the cost is increased, and the industrial large-scale application is not facilitated.

Disclosure of Invention

In view of the above, the present invention provides a method for producing a composite yarn with a graying effect, and the method of the present invention can produce a composite yarn with graying effect, which has good hand feeling and characteristics, and a short production period, and is beneficial to application.

The invention provides a production method of composite yarn with a graying effect, which comprises the following steps:

s1, opening and picking the short staple of raw cotton to make cotton bundles;

mixing a dye, polyacrylonitrile and a solvent to obtain a mixed spinning solution;

s2, carding the cotton bundles obtained in the step S1, and in the process of forming a primary color cotton web by carding cotton, performing electrostatic spinning on the mixed spinning solution to compound the formed colored nanofibers and the primary color cotton web to prepare a composite cotton sliver;

s3, the composite cotton sliver obtained in the step S2 is subjected to combing, drawing, roving and spinning in sequence to obtain the composite yarn with the effect of flower ash.

Preferably, in the step S1, polyacrylonitrile is dissolved in a solvent to obtain a polyacrylonitrile solution, and then a dye is added to the polyacrylonitrile solution to obtain a mixed spinning solution; the concentration of polyacrylonitrile in the polyacrylonitrile solution is 8-12 wt%; the mass percentage of the dye in the mixed spinning solution is 0.2-1%.

Preferably, in the step S1, the polyacrylonitrile has a weight average molecular weight of 80000-90000; the solvent is N, N-dimethylformamide.

Preferably, in the step S1, the dye added to the polyacrylonitrile solution is a commercial dye, and the dye is selected from a reactive dye, a disperse dye, a cationic dye or an acid dye; adding the dye, stirring and dissolving to obtain a mixed spinning solution.

Preferably, in the step S1, the stirring and dissolving temperature is 40 ℃ to 60 ℃, the stirring speed is 1000 r/h to 2000r/h, and the stirring time is 8h to 12 h.

Preferably, in the step S2, the voltage applied in the electrostatic spinning is 15 to 20 kV; the distance between the spray head of the electrostatic spinning and the cotton net is 20-30 cm; the speed of the cotton carding is 10-40 m/min.

Preferably, in the step S2, the mass of the colored nanofibers accounts for 2% to 5% of the mass of the composite tampon.

Preferably, in the step S2, the ambient temperature of the electrostatic spinning is 20 to 30 ℃, and the humidity is 50 to 60%; the single-nozzle filament output of the electrostatic spinning is 60-100 g/h.

Preferably, in step S1, the opening and picking process further includes a cotton blending process; in the step S3, the drawing passes through 2 to 3 passes.

Compared with the prior art, the invention takes raw cotton short fiber as the main raw material, firstly, cotton bundles are prepared through the opening and picking process, and the mixed spinning solution of dye and polyacrylonitrile is prepared; then, when cotton carding is carried out on the cotton bundles, the mixed spinning solution is prepared into colored nano fibers by utilizing an electrostatic spinning technology, and the colored nano fibers are directly compounded with primary-color cotton nets obtained by cotton carding to prepare composite cotton slivers; and finally, the composite cotton sliver is subjected to subsequent spinning procedures such as combing and drawing to produce the composite yarn with the effect of colored gray. In the cotton spinning and carding process, colored polyacrylonitrile nanofibers produced by electrostatic spinning are directly mixed into a primary-color cotton web, and finally, the composite yarn with a special effect of cotton ash can be produced through a spinning process. The mixing process in the production is simpler and more efficient, the process flow is greatly shortened, the cost is reduced, and the method is suitable for industrial large-scale production and application. The composite yarn produced by the invention has the color effect of gray and good hand feeling, and can reach the national standard in the aspects of yarn specification, various color fastness and the like.

In addition, in the production process of the colored nanofiber, pretreatment, water washing and the like are not needed for the fiber, so that the production period is greatly shortened, and the colored nanofiber is more energy-saving and environment-friendly compared with the traditional loose fiber dyeing method, and has very important significance in the industry.

Drawings

FIG. 1 is a flow chart of a process for producing a composite yarn with a colored gray effect according to an embodiment of the present invention;

FIG. 2 is a scanning electron micrograph of a composite yarn prepared according to example 1 of the present invention;

fig. 3 is a photograph of a composite yarn prepared in example 1 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

s1, opening and picking the short staple of raw cotton to make cotton bundles;

The composite yarn with the effect of the cotton gray can be prepared by the production method provided by the invention, the problems of long production period, high cost, environmental pollution and the like of the traditional pure cotton gray yarn can be partially solved, and the obtained composite yarn has good hand feeling and characteristics and can achieve the effect comparable to the pure cotton yarn.

Referring to fig. 1, fig. 1 is a flow chart of a production process of a composite yarn with a flower gray effect according to an embodiment of the present invention. The embodiment of the invention mainly takes raw cotton short fiber (short cotton short fiber for short) as spinning raw material, and adopts commercially available cotton short fiber. According to the spinning requirement, the embodiment of the invention can firstly carry out cotton blending on various raw cotton short fibers, fully play the characteristics of different raw cotton and achieve the effects of improving the product quality, stabilizing the production and reducing the cost. The present invention does not particularly require the grade and length of cotton, and raw cotton having a length of 30mm or more is preferable.

After cotton blending, the embodiment of the invention performs an opening and picking process, and cotton staple fibers can be made into cotton rolls or cotton clusters. The opening and picking process is generally the first process of the spinning process, and can be implemented by combined equipment consisting of opening and picking machines of different types, such as opening, impurity removal, mixing, coiling and the like. Wherein, opening is to open the compressed raw cotton fiber into small cotton bundles, create conditions for impurity removal and mixing, and prepare for separation into single fibers. The impurity removal is to remove 40 to 70 percent of impurities (mainly cotton seeds, sandy soil and the like) in the raw cotton while further loosening. The mixing is to uniformly mix raw cotton of various grades and the like; can be made into uniform cotton roll or cotton bunch. The opening and picking process is not particularly limited, equipment and processes which are commonly used in the field are adopted, and the manufactured cotton rolls are used for a cotton carding process. In some embodiments of the present invention, the cotton of L233A is selected as raw cotton fiber, the cotton lap impurity rate is controlled below 1% after opening and picking, and the cotton lap non-uniformity rate is controlled below 1%.

The embodiment of the invention also comprises a preparation process of the dye spinning solution, which is to mix the dye, polyacrylonitrile and a solvent to prepare a mixed spinning solution of the dye and the polyacrylonitrile. Specifically, in the embodiment of the present invention, polyacrylonitrile is first dissolved in a solvent to obtain a polyacrylonitrile solution, and then, preferably, in the stirring process, a dye is added to the polyacrylonitrile solution to obtain a mixed spinning solution.

The invention relates to a colored acrylic fiber-based nanofiber obtained by spraying in an electrostatic spinning mode, wherein the polymer raw material is Polyacrylonitrile (PAN) and is prepared by performing free radical polymerization on monomer acrylonitrile. In the examples of the present invention, the weight average molecular weight M of the polyacrylonitrile_w80000-90000, preferably 85000; the solvent is preferably N, N-Dimethylformamide (DMF). The embodiment of the invention can be stirred uniformly at room temperature to obtain polyacrylonitrile solution; the concentration of polyacrylonitrile in the obtained polyacrylonitrile solution is preferably 8-12 wt%, and more preferably 8-10 wt%.

After the polyacrylonitrile solution is obtained, the dye is added into the polyacrylonitrile solution, and the polyacrylonitrile solution can be stirred and dissolved at a certain temperature to obtain a mixed spinning solution. Wherein the mass percentage of the dye in the mixed spinning solution is preferably 0.2-1%; the mass percentage of the dye is the mass ratio of the whole mixed spinning solution. The embodiment of the invention selects the commonly used active dye, disperse dye, cationic dye or acid dye in commerce, and the commercial dyes can be dissolved in solvents such as DMF and the like to produce the electrostatic spinning colored acrylic fiber. The present invention is not particularly limited with respect to the color and the like of the dye, and a red reactive dye or a disperse dye may be used. After the dye is added, the dye is preferably stirred and dissolved; the temperature for stirring and dissolving is preferably 40 ℃ to 60 ℃. The stirring speed can be 1000-2000 r/h, and the stirring time is 8-12 h, so that the mixed spinning solution is obtained.

Cotton carding is carried out on the cotton bundles obtained in the opening and picking process; the carding process is to comb small cotton bundles into single fiber state by means of needle face motion with a flat card or roller card, further remove impurities and non-spinnable short fibers, straighten the fibers into a web in parallel, and finally make into cotton slivers which are wound into sliver cans to meet the requirements of the next process.

According to the embodiment of the invention, the electrostatic spinning of the mixed spinning solution is carried out while cotton carding is carried out on the raw cotton, and the raw cotton is compounded with the primary color cotton web. Specifically, in the embodiment of the invention, the electrostatic spinning nozzle is arranged below the carding machine, and in the running process of the carding machine, the blank web (namely, the primary color web or the white web) formed by carding is sprayed with the colored nanofibers from bottom to top by the electrostatic spinning nozzle and mixed in the white web, so that the composite cotton sliver is manufactured.

The invention uses electrostatic spinning to produce colored fiber, can be effectively combined with the cotton fiber in the cotton spinning process, continuously produces the gray yarn, does not need to additionally increase redundant flow, does not need to carry out treatment such as washing on the dyed fiber, and has the advantages of simple and efficient mixing process, easy regulation and control, energy saving and environmental protection. Meanwhile, the fibers sprayed by electrostatic spinning are nano-sized, have extremely high specific surface area, and can achieve obvious graying effect by adopting a small proportion of colored nanofibers, so that the composite yarn has good hand feeling and characteristics.

The electrostatic spinning equipment comprises a power supply unit, an injection spinning unit, a receiving unit and the like. In the embodiment of the invention, the applied voltage of the electrostatic spinning can be 15-20 kV. The distance between the nozzle of the electrostatic spinning and the cotton net is preferably 20 cm-30 cm, and effective combination of the electrostatic spinning nano-fiber yarns and the cotton fiber net is facilitated. The environment temperature of the electrostatic spinning is 20-30 ℃, and preferably 25 ℃; the environmental humidity is 50-60%. The single-nozzle filament output of the electrostatic spinning can be 60-100 g/h; the speed of carding (namely the running speed of the carding machine) is preferably 10-40 m/min, and the carding machine is suitable for large-goods production. In some embodiments of the present invention, the mass of the colored nanofibers accounts for 2% to 5% of the mass of the composite tampon, which is beneficial to obtain a composite yarn with good performance. The specific amount of the colored nanofibers is determined according to the speed of the carding machine, the number of the nozzles and the single-nozzle silk spraying amount; the lower the speed of the carding machine, the more the number of the nozzles, the larger the single-nozzle silk spraying amount and the larger the ratio of the nano fibers.

After the composite cotton sliver is obtained, the composite cotton sliver is subjected to a subsequent spinning process to prepare yarn, namely the yarn is subjected to combing, drawing, roving and spun yarn in sequence to obtain the composite yarn with the effect of cotton gray. Combing is a fine-carding cotton spinning process, short fibers and impurities in cotton fibers are removed, and long and tidy fibers are left, so that yarns with more stable quality can be spun later.

The drawing is to combine continuous strip-shaped semi-finished products (namely strips, also called as raw strips) manufactured by the previous process, so as to improve the evenness of the strips and the fiber state; the main tasks of the drawing process are merging, drafting, mixing and slivering. In the embodiment of the invention, after combing, 2-3 times of drawing are generally carried out. In the embodiment of the invention, the roving and the spinning are carried out on the drawn cotton sliver to obtain the composite yarn. The spinning process of the roving, the spun yarn, etc. is well known to those skilled in the art, and the present application is not particularly limited.

The composite yarn prepared by the invention has a special effect of colored gray and has good hand feeling and characteristics. In some embodiments of the invention, the acrylic fiber-based colored nano fiber accounts for a small proportion, for example, accounts for 2% -5% of the mass of the composite yarn, so that the effect of graying is very obvious, the hand feeling and the characteristics of pure cotton yarn can be achieved, and the application is facilitated. The method shortens the production period, reduces the production cost, lightens the influence of the production process of the pure cotton gray yarn on the environment, and has very important significance.

For further understanding of the present application, the following will specifically describe a method for producing a composite yarn with a gray effect according to the present invention with reference to examples.

In the following examples, the raw cotton staple fibers referred to were of grade L233A, a 33mm long staple cotton available from Henan New open-end textile, Inc.

Example 1

The method for producing the colored gray effect composite yarn in the embodiment comprises the following steps:

(1) the raw cotton short fibers are matched, and then the opening and picking process is carried out to prepare uniform cotton rolls. The impurity content of the cotton roll after opening and picking is controlled below 1 percent, and the non-uniformity of the cotton roll is controlled below 1 percent.

Polyacrylonitrile (specification M)_w85000) is dissolved in N, N-dimethylformamide, and the mixture is stirred uniformly at room temperature to obtain polyacrylonitrile solution; wherein the concentration of the polyacrylonitrile solution is 10 wt%; in the stirring process, adding a reactive dye Nowec cloned red FN-2BL (Huntsman company) into the polyacrylonitrile solution, wherein the mass percent of the dye is 0.8%, stirring and dissolving the dye at 40 ℃, the stirring speed is 2000r/h, and the stirring time is 10h to obtain a mixed spinning solution.

(2) Cotton beams obtained in the opening and picking process are carded (by adopting a flat card), and the raw cotton is carded and simultaneously the electrostatic spinning of the mixed spinning solution is carried out. Placing an electrostatic spinning nozzle under a carding machine, and compounding color nanofibers and white webs by the electrostatic spinning nozzle from bottom to top in the running process of a blank web of the carding machine to prepare a composite sliver;

wherein the electrostatic spinning applied voltage is 20kV, the ambient temperature is 25 ℃, the humidity is 60%, the distance between a spray head and a cotton web is 25cm, the single-spray-head silk output is 80g/h, and the running speed of the carding machine is 30 m/min; the mass of the colored nanofiber accounts for 3% of that of the composite cotton sliver.

(3) And (3) performing combing, 2-3 drawing, roving and spinning on the cotton sliver prepared in the step (2) to obtain the composite yarn with the effect of colored gray.

The scanning electron microscope photograph of the composite yarn is shown in fig. 2, wherein the thinner fibers are electrostatic spinning colored fibers, and the thicker fibers are cotton fibers. The effect of the composite yarn is shown in fig. 3, and fig. 3 is a photograph of the composite yarn. The composite yarn had a linear density of 28tex and the properties are shown in table 1:

table 1 properties of the composite yarn of example 1

From the above results, it can be seen that the electrostatic spinning composite gray yarns of the present invention have less difference in breaking strength, initial modulus, yarn evenness unevenness and the like compared to pure cotton yarns of similar specifications.

Continuously processing the colored gray composite yarn through the processes of weaving, desizing, pickling, drying and after-finishing to obtain the finished fabric (the weight of the fabric is about 180 g/m)²)。

The desizing formula and the process are as follows: mixing the raw materials in a ratio of 1: the bath ratio of 8 was 0.8g/L of deoiling agent DM-1133 (Guangdong Germany fine chemical Co., Ltd.), 2g/L of NaOH with a mass concentration of 50% and 1.5g/L of H with a specification of 27.5%₂O₂The treatment agent of the solution is desized under the conditions that the treatment temperature is 105 ℃ and the treatment time is 30 min. The acid cleaning formula and the process are as follows: mixing the raw materials in a ratio of 1: the bath ratio of 8 was adjusted to 0.5g/L HAC in the treatment agent, and the neutralization was carried out at 50 ℃ for 5 min.

The after-finishing formula and the process are as follows: the sizing is carried out by using a treating agent containing 50g/L of silicone oil softener ULTRATEX STS (Huntsman corporation), 20g/L of anti-pin-holing agent Sapamine SEW (Huntsman corporation) and 1g/L of penetrating agent FKS (Dongguan Xianqiao auxiliary agent Co., Ltd.) under the conditions that the vehicle speed is 18m/min and the treating temperature is 160 ℃.

The obtained finished fabric is subjected to color fastness test, and the result is as follows:

table 2 color fastness properties of fabrics made from the composite yarn obtained in example 1

The test results show that the color fastness of the yarn and the fabric with the gray effect all reach the national standard.

Example 2

(1) cotton matching is carried out on the raw cotton short fibers, then the opening and picking process is carried out, and uniform cotton rolls are manufactured; the impurity content of the cotton roll after opening and picking is controlled below 1 percent, and the non-uniformity of the cotton roll is controlled below 1 percent.

Polyacrylonitrile (specification M)_w85000) is dissolved in N, N-dimethylformamide, and the mixture is stirred uniformly at room temperature to obtain polyacrylonitrile solution; wherein the concentration of the polyacrylonitrile solution is 8 wt%; during stirring, adding a disperse dye TERASIL (flame red WW-GS (huntsman corporation)) into the polyacrylonitrile solution, wherein the mass percent of the dye is 0.5%, stirring and dissolving the dye at 60 ℃, and stirring the dye at 2000r/h for 12h to obtain a mixed spinning solution.

wherein the electrostatic spinning applied voltage is 15kV, the ambient temperature is 25 ℃, the humidity is 60%, the distance between a spray head and a cotton web is 20cm, the single-spray-head silk output is 100g/h, and the running speed of the carding machine is 40 m/min; the mass of the colored nanofiber accounts for 2.5% of that of the composite cotton sliver.

(3) And (3) performing combing, 2-3 drawing, roving and spinning on the cotton sliver prepared in the step (2) to obtain the composite yarn with the effect of colored gray, wherein the linear density of the yarn is 18.5 tex.

According to the embodiment, in the cotton spinning and carding process, the colored polyacrylonitrile nanofibers produced by electrostatic spinning are directly mixed into the primary-color cotton web, and finally the composite yarn with the special effect of the cotton ash can be produced through the spinning process. The mixing process in the production is simpler and more efficient, the process flow is greatly shortened, the cost is reduced, and the method is suitable for industrial large-scale production and application. In addition, in the production process of the colored nanofiber, pretreatment, water washing and the like are not needed for the fiber, so that the production period is greatly shortened, and the colored nanofiber is more energy-saving and environment-friendly compared with the traditional loose fiber dyeing method. The composite yarn produced by the invention has the color effect of gray and good hand feeling, and can reach the national standard in the aspects of yarn specification, various color fastness and the like.

The above description and examples are intended to illustrate the scope of the invention, but are not intended to limit the scope of the invention. Modifications, equivalents and other improvements which may occur to those skilled in the art and which may be made to the embodiments of the invention or portions thereof through a reasonable analysis, inference or limited experimentation, in light of the common general knowledge, the common general knowledge in the art and/or the prior art, are intended to be within the scope of the invention.

Claims

1. A production method of composite yarn with a colored gray effect comprises the following steps:

s1, opening and picking the short staple of raw cotton to make cotton bundles;

firstly, dissolving polyacrylonitrile in a solvent to obtain a polyacrylonitrile solution, and then adding a dye into the polyacrylonitrile solution to obtain a mixed spinning solution; the concentration of polyacrylonitrile in the polyacrylonitrile solution is 8-12 wt%; the mass percentage of the dye in the mixed spinning solution is 0.2-1%; the weight average molecular weight of the polyacrylonitrile is 80000-90000; the solvent is N, N-dimethylformamide;

s2, carding the cotton bundles obtained in the step S1, and in the process of forming a primary color cotton web by carding cotton, performing electrostatic spinning on the mixed spinning solution to compound the formed colored nanofibers and the primary color cotton web to prepare a composite cotton sliver; the mass of the colored nano fiber accounts for 2-5% of that of the composite cotton sliver;

2. The production method according to claim 1, wherein in the step S1, the dye added to the polyacrylonitrile solution is a commercial dye selected from a reactive dye, a disperse dye, a cationic dye or an acid dye; adding the dye, stirring and dissolving to obtain a mixed spinning solution.

3. The production method according to claim 2, wherein in the step S1, the stirring and dissolving temperature is 40-60 ℃, the stirring speed is 1000-2000 r/h, and the stirring time is 8-12 h.

4. The production method according to any one of claims 1 to 3, wherein in the step S2, the applied voltage of the electrostatic spinning is 15 to 20 kV; the distance between the spray head of the electrostatic spinning and the cotton net is 20-30 cm; the speed of the cotton carding is 10-40 m/min.

5. The production method according to claim 4, wherein in the step S2, the ambient temperature of the electrostatic spinning is 20-30 ℃, and the humidity is 50-60%; the single-nozzle filament output of the electrostatic spinning is 60-100 g/h.

6. The production method according to any one of claims 1 to 3, characterized in that in step S1, the opening picking process is preceded by a cotton blending process; in the step S3, the drawing passes through 2 to 3 passes.