Preparation method of gray yarn
Technical Field
The invention belongs to the field of yarn preparation, and particularly relates to a preparation method of gray yarn.
Background
The grayish effect is popular with consumers, and occupies a large share proportion in daily clothing commodity consumption. However, the traditional manufacturing process is relatively laborious and time-consuming, and particularly for cotton ash, the manufacturing process involves many and complicated procedures. The key point is that the manufacturing process can also damage the cotton fiber, so that the quality standard of the finished yarn can not meet the standard requirement of the conventional yarn.
Traditional cotton gray yarn manufacturing process: cotton-loose fiber pretreatment-loose fiber dyeing and drying, and the like-mixing with white cotton to form grey flower, spinning, weaving and cleaning.
There are several biggest problems in this production flow:
1 yarn is not pure: in order to balance the strength of loose fibers and the impurity removal degree of pretreatment, the pretreatment conditions are much milder than those of the pretreatment of the fabric. The quality of the finished yarn is not high, and a plurality of garments even have the problem of residual cotton seed hulls;
2 fiber length and strength reduction: the working procedures of pretreatment, dyeing and the like cause the length and the strength of the whole fiber to be substantially reduced, and the resultant yarn also has entrusts of excessive hairiness and the like, so that the quality effect of the finished fabric product is poor;
3, the flexibility is insufficient: the color of the gray yarn is mainly dyed by loose fibers at the front end, and compared with the net dyeing of the fabric, the mass production and the flexibility are greatly limited. The required color can not be dyed at any time by preparing gray fabric as fabric dyeing. And the production cycle of the gray yarn is long, basically more than 90 days, and is more than twice of the production cycle of the conventional fabric. And electrolytes such as saline-alkali electrolytes are not required to be added in the dyeing process, so that the sewage discharge is reduced.
4 adding functional additive in the later process,
CN1654729A discloses a method for manufacturing pure cotton fancy yarn without flying-flower pollution, the manufacturing method of the cotton gray yarn is disclosed, a method for modifying cotton fiber cation is adopted, and the process flow is as follows: modifying cotton cations, mixing with raw cotton, carding and spinning. The whole process is consistent with the traditional grey yarn process flow. Its advantages are that it can be dyed after finished yarn, and the limit of dyeing color is not very limited. But the whole process flow is not different from the production flow of the conventional grey yarn process, and the defect that cotton is mixed after the single treatment is still needed.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a method for preparing gray yarn, which overcomes the technical defects of long process flow and low efficiency in the prior art, the whole process of the invention does not change the normal process of conventional spinning, the modification is finished in the cotton carding process, the cylinder treatment is not needed, and the production cost is reduced.
The invention relates to a preparation method of gray yarns, which comprises the following steps: cotton blending, cotton carding, spinning, weaving and dyeing; in the cotton carding process, electrostatic spinning is carried out to modify fibers and the fibers are directly loaded on a cotton web;
wherein the spinning solution adopted by electrostatic spinning comprises a polymer carrier, a cationic modifier and an antibacterial agent.
Namely, the electrostatic spinning fiber carries the cation modifier as a cation modification system and an antibacterial system, and is directly loaded on the cotton net.
The preferred mode of the above preparation method is as follows:
the mass ratio of the modified fiber to the cotton web is 1: 10 to 25.
The diameter of the cation modified fiber is 200-500 nm.
The electrostatic spinning cation modified fiber comprises the following specific components: preparing spinning solution containing a polymer carrier, a cationic modifier and an antibacterial agent, and performing electrostatic spinning; the electrostatic spinning voltage is 30-80 KV, the cotton net is directly used as an electrostatic spinning receiving device, and the electrostatic spinning modified fibers are directly loaded on the cotton net.
The polymer carrier is one or more of polyurethane PU, polyvinyl alcohol PVA and polyacrylonitrile PAN.
8-15 million of polyurethane PU, 5-12 million of polyvinyl alcohol PVA, and 5-12 million of polyacrylonitrile PAN molecular weight.
The cationic modifier is a copolymer of a modified isocyanate reactive group and a quaternary ammonium salt cationic modified group, wherein the reactive group is combined with cotton in a modification process to form a graft, and the quaternary ammonium salt is an introduced dyeing group for dyeing dyes; the antibacterial agent is quaternary ammonium salt cation antibacterial agent.
The cationic modifier is a German chemical color medium, and the molecular weight is about 500; the antibacterial agent is SCJ-877 with molecular weight of about 600.
The mass concentration of the polymer carrier in the spinning solution is 5-15%; the mass concentration of the cation modifier is 10-50%, and the concentration of the antibacterial agent is 1-5%.
The dosage of the cationic modifier is 1-5% by mass (OWF), the dosage of the antibacterial agent is 0.1-0.5% by mass (OWF), namely the dosage of the cationic modifier is 1-5% by mass of the whole cotton net and the dosage of the antibacterial agent is 0.1-0.5% by mass of the whole cotton net relative to the mass of cotton.
The process comprises the following steps of carrying out grey cloth sizing treatment before dyeing, wherein the process parameters are as follows: setting for 1-3 min at 90-170 ℃, increasing a grey cloth setting process and improving the fastness of cationic modification.
Preferably, the grey cloth is sized at 130 degrees for 2 minutes to complete the crosslinking of the cationic modifier.
And (4) pretreatment before dyeing, wherein according to the brightness of subsequent dyeing, 5-20 g/l of sodium carbonate and 0-5 g/l of 30% hydrogen peroxide are adopted.
Anionic dyes such as reactive dyes, acid dyes or direct dyes can be used in the dyeing process, the dyeing solution is boiled at 98 ℃ for 30-60 minutes according to the color depth, and the pH value of the dyeing solution is controlled to be 4.5-6.
The gray yarn prepared by the method is provided by the invention.
The invention relates to an application of the gray yarn.
In the invention, a cationic modifier is applied to a cotton net in a linear mode by an electrostatic spinning process; preferably, the cation modifier is a German and American chemical color medium produced in a mass transfer mode, the dosage of the German and American chemical color medium is 1-5 percent (relative to the mass percentage of cotton, namely the mass of the cation modifier accounts for 1-5 percent of the mass of the whole cotton net), the antibacterial agent is a clean and comfortable quaternary ammonium salt cation antibacterial agent SCJ-877 (Beijing Jiershuang high-tech company), the concentration of the antibacterial agent is 1-5 percent, and the electrostatic spinning medium is PU, PVA or PAN; the electrostatic spinning cationic modifier application is carried out in the cotton yarn carding process. The electrostatic spinning superfine filament is used as a carrier, and a cation modifier is combined with cotton fiber in a linear mode (the linear mode refers to that the filament extracted by electrostatic spinning is linear, and the cation modifier carried by the filament is attached to the cotton fiber in a linear mode and is modified so as to ensure that dyeing linearity is presented instead of agglomeration after dyeing). So as to form local modification to the cotton fiber and avoid the influence of local aggregation formed by spraying and other modes on the dyeing effect.
The gray yarn of the invention adopts an electrostatic spinning process, utilizes high molecular materials such as PU, PVA or PAN and the like as carriers, and linearly applies German and American chemical color media as a cation modifier to a cotton net. Meanwhile, local cationic modification of cotton fibers is realized by utilizing the characteristic that the diameter of the electrostatic spinning submicron fibers is far lower than that of cotton fibers (the diameter of the cotton fibers is 20 microns (200000 nm)). The diameter of the cation modified fiber is 200-500 nm, if the diameter of the fiber is too large, the comparative area of the cation modified fiber is reduced, the following problems can occur, the cation modifier on one belt can be reduced greatly, and the modification efficiency is not high; secondly, the modified fiber can not be attached to the surface of a single fiber, so that the local modification effect is poor; thirdly, the excessive diameter will affect the quality of the yarn.
Advantageous effects
(1) In the cotton carding process, the cation modifier is added to the cotton net in a linear mode through an electrostatic spinning process and is mixed with the cotton to achieve the purpose of locally modifying the cotton, the local coloring effect is achieved through single dyeing of the modified cotton, and the final finished product is consistent with the gray cotton.
(2) The cationic antibacterial agent and the cationic modifier have synergistic effect, and the effect of the gray yarn is realized, and meanwhile, the yarn is endowed with good antibacterial effect.
(3) The whole process is consistent with the net color dyeing process, and the production efficiency and the flexibility are greatly improved.
(4) The invention uses the electrostatic spinning process to realize the linear application of the cationic modifier and prevent the damage of local aggregation to cotton fibers, the modification process is linear rather than granular local modification, and the uniformity of cotton modification is improved.
(5) The production period and the stock are greatly reduced, the production cost is reduced, and the product quality is not affected basically.
(6) The process of the invention can not only effectively avoid cation modification aggregation generated by spraying and other modes and damage to fibers, but also reduce the influence on the yarn quality. Compared with the traditional process flow, the process flow of the gray yarn production can be shortened (the traditional process flow comprises dyeing cotton, mixing with white cotton, cotton carding and spinning, the cotton needs loose fibers to be dyed in a cylinder, the whole process needs 28 days, and each color needs to be customized in advance), and the novel process flow of the invention comprises the following steps: cotton carding, modification and spinning, the whole process does not change the normal flow of conventional spinning, and the whole process only needs 5 days. Furthermore, the method is simple. The dyeing color is not limited, the dyeing is more flexible, the production cost is reduced, and the production efficiency and the production flexibility are improved.
Drawings
FIG. 1 is a schematic diagram of the effect of partial cationic modification;
FIG. 2 is a graph showing the effect of linear cationization coating; a, B, C, D the modification effect of different magnification electrostatic spinning fiber on cotton fiber, wherein the coarse fiber is cotton and the fine fiber is electrostatic spinning fiber. The figure shows that local linear modification of cotton can be realized through the electrostatic spinning process, so that the effect of grey dyeing is achieved.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
PU with molecular weight of 5-12 ten thousand; (Shanghai national drug group chemical reagent Co., Ltd.)
The cationic modifier in the examples is derived from a German chemical color medium and has a molecular weight of about 500.
The cotton is conventional 129 cotton, and the diameter of cotton fiber is about 20 μm.
In the examples, the antibacterial agent is quaternary ammonium salt cationic antibacterial agent SCJ-877 of Beijing Jiejieshuang high tech company, and the molecular weight is about 600.
The preparation device is a paving and electrostatic spinning combined device (electrostatic spinning equipment is added on a common carding machine), and can be seen in CN 110295399A.
Example 1
The production process of the pure cotton cation modified 16-count plain-line safflower gray cloth comprises the following steps:
the process flow comprises the following steps: cotton preparation, cotton carding, cation modification, antibiosis, spinning, weaving, grey cloth shaping, dyeing and finished product.
The main technical indexes are as follows:
the cotton carding and cation modification method specifically comprises the following steps: in the cotton carding process in the production of cotton yarns, the cationic modifier is applied linearly to the web (the web acts directly as a receiving device) using an electrostatic spinning process: the electrostatic spinning voltage is 50KV, the distance between a spinning nozzle and a cotton net is 12CM, the mass percentage concentration of a used electrostatic spinning carrier PU is 10%, the molecular weight is about 10 ten thousand, the mass percentage concentration of a cation modifier is 30%, the mass percentage concentration of an antibacterial agent SCJ-877 is 3% (a spinning solution solvent is water), and the diameter distribution of the obtained cation modified fiber is 200-300 nm.
Wherein the mass ratio of the cation modified fiber to the cotton web is 1: 20; a cationic modifier in an amount of 1.5% (OWF) and an antimicrobial in an amount of 0.15% (OWF).
Blank setting: 130 degrees 2 minutes.
Dyeing: the formula comprises active red 3BS 2.5% OWF and active yellow 3RS 0.1 OWF.
Dyeing conditions water ratio of 1: 8(1 kg of cloth, 8 kg of water is needed for soaking and dyeing), 98 ℃ for 45 minutes, and the pH value of the dye solution is 4-5.
Table 116S plain weave fabric test results
Example 2
The production process of the pure cotton cation modified 30 count pure cotton thread black gray cloth comprises the following steps:
the process flow comprises the following steps: cotton preparation, cotton carding, cation modification, antibiosis, spinning, weaving, grey cloth shaping, dyeing and finished product.
The main technical indexes are as follows:
the cotton carding and cation modification method specifically comprises the following steps: in the cotton carding process in the production of cotton yarns, the cationic modifier is applied linearly to the web (the web acts directly as a receiving device) using an electrostatic spinning process: the electrostatic spinning voltage is 50KV, the distance between a spinning nozzle and a cotton net is 10cm, the mass percentage concentration of the used electrostatic spinning carrier PU is 10%, the molecular weight is 12 ten thousand on average, the mass percentage concentration of the cationic modifier is 40%, the dosage of the antibacterial agent SCJ-877 is 2% (the spinning solution solvent is water), and the diameter distribution of the obtained cationic modified fiber is 250-350 nm.
Wherein the mass ratio of the cation modified fiber to the cotton web is 1: 10; a cationic modifier in an amount of 4% (OWF) and an antimicrobial in an amount of 0.2% (OWF).
Blank setting: 130 ℃ for 2 minutes;
dyeing: the formula comprises 4.5% of active black B, 0.3% of active yellow 3RS and 0.4% of active red 3 BS.
Dyeing conditions water ratio of 1: 8(1 kg of cloth, 8 kg of water is needed for soaking and dyeing) at 98 ℃ for 60 minutes, and the pH value of the dye solution is 4-5.
TABLE 230S thread profile test results
FIG. 1 shows a theoretical model of coating modification, in which spun yarn partially represents electrospinning; the roving fraction, which represents the cotton fiber, is the main reason for the effect of electrostatic spinning on the local modification of cotton, which is the effect of the formation of grey yarns.
Fig. 2 shows the formation of the yarn by electrospinning on cotton fibers, wherein the coarse fibers are cotton and the fine fibers are electrospun. The figure shows that local linear modification of cotton can be realized through the electrostatic spinning process, so that the effect of dyeing the cotton ash is achieved, and meanwhile, the electrostatic spinning forms better linear coating on cotton fibers.
Comparative example 1
Compared with CN1654729A, the gray yarn obtained by the invention has the following advantages:
1, the efficiency is improved, and the normal production period is 20 days by the method of CN 1654729A; the method has the advantages that the normal production period is 5 days, and the efficiency is improved by 75 percent.
2, the cost is reduced, in the mode of CN1654729A, the dyeing vat is firstly used for cation, then the dyeing vat is dried and then is mixed with the common cotton, and the dyeing cost is increased by about 15 yuan/kg; all the processes of the invention are basically carried out according to the normal spinning process, only the electrostatic spinning process and the cost of related auxiliary agents are added, and the cost is increased by about 5 yuan/kg. The cost per kilogram can be saved by 10 yuan.
3, the yarn forming effect is better, and the content of short fibers in cotton can be increased in the process of cation modification by feeding CN1654729A into a cylinder, so that the problems of more yarn hairiness and the like are caused. This is also the reason why the quality of the marbled grey fabric is slightly poor in daily life. The method has no step of cylinder entering, can not cause the problem of cotton fiber fibrillation, and the resultant yarn is basically close to the effect of the conventional yarn.
4 dyeing performance and effect are basically consistent.
Table 3: the antibacterial synergistic effect data prove that: