KR0151369B1 - Dyeing process for the superfine non woven fabric leatherette - Google Patents

Abstract

The present invention relates to a dyeing method of microfibre nonwoven artificial leather, the dyeing method of the microfibre nonwoven artificial leather according to the present invention is first impregnated with a polyurethane resin and treated with a pigment, using a metal complex dye dye at 50 to 100 ℃ 120 Dyeing and washing for 70 minutes, and then reducing the dyeing of the bubble with a vat dye corresponding to the range of 10-15% by weight of the metal complex dye dye, oxidizing and coloring, and then soaping treatment, and then washed with an anion-type softener It is characterized by drying.

According to the present invention, there is no dyeing stain, excellent dyeing fastness in dark colors, and having a touch similar to that of natural leather, thereby providing artificial leather that can be widely applied to the field of general merchandise that can substitute for leather as well as medical fields. It works.

Description

Dyeing method of microfibre nonwoven artificial leather

The present invention relates to a dyeing method of microfibre nonwoven artificial leather, and more particularly, dyeing of microfiber nonwoven artificial leather which greatly improves washing fastness and friction fastness by pigment treatment of bubble paper, proper selection and blending of dyes, and flexible processing. It is about a method.

In general, artificial leather is made of chemical fiber material, which is similar to natural leather in appearance and appearance, and the basic material is divided or island-in-the-sea composite fiber microfiber or general microfiber manufactured by mixed spinning or composite spinning method. It is a high-tech chemical fiber material developed and commercialized mainly in Japan and Korea.

Conventionally, a suede artificial leather manufacturing method is that when the fiber is polyethylene terephthalate, a small amount of pigment is added to the polyurethane elastomer solution, filled into a non-woven fabric of ultrafine fibers, wet-coagulated, dyed with a disperse dye, and reduced washing. To remove the dye physically bound to the polyurethane. In other words, only the fibers are dyed in the dye and the polyurethane elastomer is colored with the pigment. This method makes it difficult to control the color difference between the fibers and the polyurethane, and the color of the polyurethane is not clear. There were a lot of problems. Similarly, when the fibers were nylon, dyes were not colored on polyurethane, making it difficult to produce artificial leather with excellent dyeability.

The fundamental reason for this is that there is no functional group having affinity with acid dyes such as amines in the chemical structure of the polyurethane. If the polyurethane elastic body can be provided with a functional group having affinity with dyes without a change in physical properties other than polyurethane, Much research has been carried out with the idea that it is possible to manufacture suede artificial leather that is not only uniform and clear but also has excellent color depth and color fastness.

For example, ① a method of introducing a amine or the like containing tertiary nitrogen into a soft block or a hard block of polyurethane as a chlorinated functional group (Japanese Patent Publication No. 62-23097), ② an organic acid or an inorganic acid and a tertiary A method of introducing a salt with an amine into a polyurethane polymer chain (Japanese Patent Publication No. 50-17520), ③ A method of introducing a tertiary or quaternary nitrogen atom to the terminal of the polyurethane polymer chain (Japan Korean Patent Publication No. 44-16386), (4) A method of using a low molecular diamine as a chain extender (Japanese Patent Publication No. 59-108021), and the like have been used. However, methods ① and ② are easy to gel during the reaction, and method ③ has a problem that it is difficult to control the amount of nitrogen atoms introduced, and method ④ can improve the dyeability, but has a problem of lowering softness and elasticity. .

The method described above is a method of improving the color fastness and color fastness by introducing a chlorinated group or changing the physical properties of the polyurethane elastomer used in the coating, but it is advantageous in terms of improving color development, but hardens the feel of the final product It has disadvantages and is not advantageous in terms of color fastness, but has difficulty in manufacturing process (deterioration of properties during long-term storage).

Artificial leather is considered to be a very fascinating material in terms of the appearance, feel and performance of its final product, especially in that it can be washed and freely diversified in color. It is a material that requires very difficult technology.

In the dyeing of artificial leather, conventionally, a polyamide microfiber base is impregnated with a solution of a polymer mainly composed of a polyurethane elastomer, followed by solidification and surface raising treatment, and dyeing, that is, a suede-like hair sheet by a post dyeing method. It was common to prepare. Generally, polyamide-based fibers such as nylon-6 are dyed using acid dyes, disperse dyes, metal complex dyes, and the like, and are known to have a functional relationship between the fineness of fibers and the dye concentration used.

The formula is called the formula of Forthergill, wherein C ₁ represents the dye usage in D ₁ denier, and C ₂ represents the dye usage in D ₂ denier.

It can be seen that in order to obtain the same coloring effect, the amount of dye used is inversely proportional to the square root of the fineness. In other words, the finer the fineness, the greater the amount of dye used. Therefore, in artificial leather employing microfiber with a very low fineness of fiber, the amount of dye used during dyeing is very high, and it is very difficult to improve the wet dyeing fastness particularly in deep colors. In addition, the light fastness of artificial leather is also lower than that of ordinary fibers. The reason for this is that microfibers have a very large fiber surface area than ordinary fibers, so they absorb more light and increase energy conversion from light to heat. It is said that it is because the deviation of more.

In the case of ultra-fine fibers of less than 1 denier, color development becomes poor due to the increase in the amount of surface reflection light, and dyeing using a high concentration of dye bath is difficult to obtain dark colors, and color fastness is also insufficient. do. For example, a type 1: 2 metal complex dye in which a dye molecule is coordinated with two metal atoms is used. Among them, a dye having a weak hydrophilic group such as a sulfone amide group or a sulfone methyl group or an asymmetric type having a small number of sulfonic acid groups or Symmetric metal-containing dyes are used.

The method of obtaining suede-like artificial leather with good color development and color fastness by dyeing with a dye mainly composed of the metal complex dyes described above is Japanese Patent Laid-Open No. 61-25834, 63-303187. And Patent Publication No. 1-192884.

On the other hand, polymer elastomers such as polyurethane have low alignment properties of the film, and instead of easily adsorbing the dye, the loose molecular structure facilitates the removal of the dye, which is one of the major factors that lowers the dye fastness.

A method of dyeing polyamide-based ultrafine fiber products of 0.02 denia or less treated with polyurethane with a metal dye and then performing a fixation treatment with tannic acid and a metal salt is disclosed in Japanese Patent Laid-Open No. 60-252784. have. However, in artificial leather, it is required to give a very similar appearance and feel to natural leather, and to impart invisible coloring balance and dyeing fastness to natural leather, which is treated with tannic acid and metal salts to increase dyeing fastness of polyamide fiber. It is hard to express a texture similar to that of natural leather by stiffening the touch, and due to the excess dye required for dyeing, the fixing effect is halved and a problem occurs in color reproduction.

On the other hand, the coloring of the conventional artificial leather is different depending on the material, the fineness and the composition ratio, but not uniform, but the pigment is used in combination with a polymer resin, a solvent and the like by a pad method, a gravure printing method, dyes, for example For example, disperse dyes, acid dyes, metal-containing dyes, oil-soluble dyes, etc., mixed with resins and colored by printing, gravure printing, etc., have an effect on the surface bending resistance, but they swell the fibers or excessively Close contact damages touch, breathability and moisture permeability.

In general, in the case of dyeing artificial leather by the dyeing method commonly used for dyeing polyamide fibers, the dyeing is carried out at a relatively high temperature, for example 90 to 110 ℃ in Japanese Patent Laid-Open No. 55-71841. Therefore, there is a problem in that dyeing unevenness between the napped fibers of the polyamide and the polyurethane bubbles, an imbalance of the surface nipple, etc. occur with or without a solvent, and in addition, there is a problem that it is easy to damage the touch and appearance with the scattering of the nipple.

Therefore, the present inventors treated artificial leather bubble paper with a suitable ratio of pigment, mixed and used the dye and dry dyes in an appropriate ratio, and by fastening treatment in the post-treatment process color fastness dyeing and color to maintain washing durability and high friction fastness We have succeeded in obtaining this vivid, deep color and soft touch non-woven artificial leather product.

Accordingly, an object of the present invention is to provide a dyeing method of microfiber nonwoven artificial leather that can exert a color fastness and color fastness and excellent washing fastness and friction fastness.

The dyeing method of the microfibre nonwoven artificial leather according to the present invention is first impregnated with a polyurethane resin and treated with a pigment, dyed with water and dyed for 50 to 70 minutes at 100 to 120 ℃ using a metal complex dye, and the metal is further complex It is characterized in that it is reduced dyeing and oxidative coloring with a vat dye corresponding to 10 to 15% by weight of the dye use, followed by soaping treatment, and then washed with an anion-type softener and washed with water.

The present invention will be described in more detail below.

Polyurethanes used in the present invention are organic diisocyanates and aromatic diisocyanates and 1,6-hexamethylene diisocyanates, including 4,4'-diphenylmethane diisocyanate, which are generally used when preparing polyurethane for artificial leather. And aliphatic diisocyanate, including isophorone diisocyanate, and aliphatic diisocyanate including polyisoethylene, and polytetramethylene glycol as polymer diol and N, N-dimethylformamide as organic solvent.

On the other hand, any fiber can be used as long as the fiber used in the present invention has a fineness of 5D or less, but in the final product, a good lighting effect cannot be exhibited unless it is 0.5D or less. Since such microfibers cannot be used for the initial production of nonwoven fabrics, if the fiber polymers made of continuous polymer filament concentrates having a certain diameter are spun simultaneously in a composite spinning form, the binders are divided or dissolved in the post-processing process to remove the useless components. The final fiber is made of ultrafine fibers of 0.5D or less. As the type of fiber polymer that can be used, any one can be used as long as it has a fiber forming ability such as polyester, polyamide, polyacrylonitrile, and as the polymer lump, polystyrene, a derivative of polystyrene, low density polyethylene, polyethylene terephthalate, etc. can be used. Do.

Various methods have been considered as a method of manufacturing the nonwoven fabric, but it is effective to apply the present invention to a three-dimensional entangled nonwoven fabric having a weight of 250 g / m 2 to 600 g / m 2 by carding, cross lapping, and needle punching.

Next, the pigment treatment, the dyeing method of combined dyeing and the post-treatment method will be described in detail.

First, the pigment treatment of bubble paper is mixed with a suitable amount of pigment in a resin having a solid content of 50% or less, and then squeezed in a mangle at 65 to 75% of the thickness of the bubble paper, and then 5 to 20 minutes at 90 to 100 ° C. Dry to obtain bubble paper. Staining was performed using a neutral to weakly acidic metal complex dye and acid concentration was controlled using ammonium sulfate.

As the penetrating leveling agent, anionic penetrating agent of sodium dialkyl sulfosuccinate composition was used for the nonionic leveling agent and the dense nonwoven artificial leather structure.

Neutral to weakly acidic metal salt dyes used in the present invention have the property of dyeing slowly and uniformly within the acidity of 5.5 to 7, and this dye penetrates well into dense fabrics and has no fiber selectivity and is also used for washing and milling. The high fastness to is also because desorption from the swollen fibers is prevented because they are associated in a solution up to about 50 ° C.

The dyeing using the dye and the preparation is heated to 1.0 ° C / min or less in the low temperature region, 0.5 to 1.5 ° C / min in the high temperature region from the fact that a significant amount of dye is absorbed in the low temperature region due to the dyeing characteristics of nylon, After dyeing by leveling at 100 to 120 ° C. for 40 to 60 minutes, the dye is cooled to 0.5 to 1.5 ° C./minute up to 50 ° C., and acetic acid is added while leveling at 50 ° C. for more than 30 minutes to maximize dye absorption.

Under the neutral color, even if dyed in the same manner as above, a good fastness is obtained, but in the neutral color more than a deep color, the pollution and friction fastness other than washing are poor. Thus, in order to meet the fastness target, the dye is dyed using a vat dye, and a dye is used at a concentration in the range of 10 to 15% by weight of the amount of the metal complex dye used. Dyeing dyes have a carbonyl group (C = O) as a unique chromophore, which is insoluble in water and alkali and soluble in alkali by alkaline reducing agents. It is adsorbed on the fiber and then contacted with air to oxidize to regenerate carbonyl group to achieve the purpose of dyeing. As such, the vat dyes do not contain a soluble group and thus belong to the class having good washing fastness and daylight fastness.

Tren dye of the vat dye is most suitable for dyeing polyamide fiber, the dyeing temperature is preferably 40 to 80 ℃, the dyeing time is 20 to 50 minutes. When dyeing, it is preferable to use the neutral dye in accordance with the required color rather than the combination using three primary colors in terms of reproducibility or dye nonuniformity.

The dyeing paper dyed as described above is subjected to oxidative color development in the next step, soda perborate is used as the oxidizing agent, the treatment temperature is preferably 70 to 90 ℃, the treatment time is 10 to 30 minutes, the final soaping (Soaping) Using an anion type soaping agent, the treatment temperature is preferably 70 to 90 ° C., and the treatment time is 10 to 30 minutes. The dyeing paper thus obtained is treated with an anion type softener to wash and dry the final desired product. Get

Hereinafter, specific examples of the present invention and comparative examples for comparison will be described. However, the following examples are not intended to limit the spirit and scope of the present invention.

Example 1

4 denier (D) x 51mm of sea island type composite fiber (36 degrees) which made nylon-6 into microfine fiber (70 weight part), and polyethylene terephthalate as ultrafine fiber aggregate (30 weight part) A three-dimensional entangled nonwoven fabric weighing 300 g / m 2 was made by stapling / inch stapling, carding, cross-lapping and needle punching. This was treated with an aqueous sodium hydroxide solution to completely remove the polyethylene terephthalate, and then dried to give a form stability by binder treatment with an aqueous polyvinyl alcohol solution.

Next, 5 parts by weight of the pigment was mixed with 100 parts by weight of the polyurethane elastomer solution, and the nonwoven fabric prepared above was impregnated, coagulated in water, and washed with hot water to remove the water-soluble polyvinyl alcohol.

The leather sheet obtained by drying it is buffed with sandpaper, and the metal complex dye for neutral bath (1: 2 alloy dye) 5% owf, pH adjusting agent 2g / L, nonionic penetrating leveling agent 1% owf, anionic penetrating leveling agent 1% owf Dyeing at a temperature increase rate of 0.6 ℃ / min in the low temperature region, dyeing at a temperature rising rate of 1.2 ℃ / min to the high temperature region, and dyeing by leveling at 100 ℃ 60 minutes 60 ℃ 1 ℃ / Cooling to minutes and leveling at 50 ° C. for 30 minutes added an appropriate amount of acetic acid (2% owf or less) to maximize dye absorption.

After washing the non-woven artificial leather dyed with a metal dye as described above and treated with a trench dry dye 1% owf at 80 ℃ for 10 minutes, and then treated with an anion-type softener to wash and dry the final process of the present invention Dyeing of microfibre nonwoven artificial leather is completed.

Comparative Example 1

In Example 1, dyeing and washing with a metal-containing dye were followed by fixation treatment and non-fixing treatment without dyeing with a vat dye and soaping and casting treatment with an anionic softener and a softening agent.

Example 2

The concentration of the metal complex dye for the neutral bath was 10% o.w.f., and the concentration of the dry dye was 2% o.w.f., and the remaining conditions were dyed in the same manner as in Example 1.

Comparative Example 2

After staining and washing with a metal-containing dye in Example 2, the dyeing treatment and non-sticking treatment were performed without dyeing with a vat dye and soaping and casting treatment with an anionic softener and a softening agent.

Various fastnesses and touches of the products dyed in the above Examples and Comparative Examples were evaluated and shown in Table 1 below.

As shown in Table 1, the non-woven artificial leather according to the embodiment of the present invention was excellent in deep color, friction, washing and daylight fastness of all three or more, rich in touch and elasticity.

According to the present invention, there is no dyeing stain, excellent dyeing fastness in dark colors, and having a touch similar to that of natural leather, thereby providing artificial leather that can be widely applied to the field of general merchandise that can substitute for leather as well as medical fields. It works.

Although the invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that changes and modifications can be made within the spirit and scope of the invention and such changes or modifications are limited by the appended claims. You must lose.

Claims (14)

Impregnated and pigmented the microfiber nonwoven artificial leather bubble cloth, and dyed and washed it at 50 to 70 minutes at 100 to 120 ° C. using a metal complex dye, and then the bubble was 10 to 15% by weight of the metal complex dye used. The dyeing method of the microfibre nonwoven artificial leather, characterized in that the dyeing, reducing and oxidizing color with a dry dye corresponding to the range, followed by soaping treatment, and then washed with water by drying with an anionic type softener. The method of claim 1, wherein the polyurethane is an organic diisocyanate containing an aromatic diisocyanate including 4,4'-diphenylmethane diisocyanate, aliphatic diisocyanate including 1,6-hexamethylene diisocyanate, and isophorone diisocyanate. Method for dyeing the microfiber nonwoven artificial leather, characterized in that it is selectively used in aliphatic diisocyanate. The method of claim 1, wherein the polyurethane resin impregnation solution is prepared using polytetramethylene glycol as polymer diol and N, N-dimethylformamide as an organic solvent. The method of dyeing the microfiber nonwoven artificial leather according to claim 1, wherein the microfiber fiber material is polyester, polyamide, or polyacrylonitrile. 2. The method of dyeing the microfiber nonwoven artificial leather according to claim 1, wherein the component eluted and removed when the microfiber is manufactured by the island-in-the-sea composite fiber is one of polystyrene, a derivative of polystyrene, low density polyethylene, and polyethylene terephthalate. . The method of claim 1, wherein the nonwoven fabric is a three-dimensional entangled nonwoven fabric produced by carding, cross-lapping, needle punching, the weight of the microfiber nonwoven artificial leather, characterized in that the weight is 250g / ㎡ to 600g / ㎡. The method of claim 1, wherein the pigment treatment of the bubble paper is mixed with a suitable amount of pigment in a resin having a solid content of 50% or less, and then woven in a mangle of 65 to 75% thick of the bubble paper thickness, 90 to 100 Method for dyeing the microfiber nonwoven artificial leather, characterized in that it is made by drying for 5 to 20 minutes at ℃. The dyeing method of the microfiber nonwoven artificial leather according to claim 1, wherein a neutral to weakly acidic metal complex dye is used as the metal dye during the dyeing process, and an acid concentration is controlled by using ammonium sulfate. The microfiber yarn according to claim 1, wherein a non-uniform leveling agent and an anionic penetrating agent of a sodium dialkyl sulfosuccinate composition are used as the penetration leveling agent in the dyeing step with the metal-containing dye. Dyeing method of nonwoven artificial leather. The method of claim 1, wherein the dyeing with the metal-containing dye is raised to 1.0 ℃ / min or less in the low temperature region, 0.5 to 1.5 ℃ / minute in the medium temperature range, and 40 to 60 minutes at 100 to 120 ℃ After dyeing by leveling (leveling) and cooling to 0.5 to 1.5 ℃ / min to 50 ℃ and leveling at 50 ℃ for more than 30 minutes dyeing of the microfibre nonwoven artificial leather, characterized in that to increase the absorption rate of the dye as much as possible Way. The dyeing method of the microfiber nonwoven artificial leather, characterized in that the dyeing is carried out at a dyeing temperature of 40 to 80 ℃, dyeing time 20 to 50 minutes. The dyeing method of the microfiber nonwoven artificial leather according to claim 1, wherein the oxidation-coloring treatment process uses soda perborate as an oxidizing agent, a treatment temperature is 70 to 90 캜, and a treatment time is 10 to 30 minutes. . The dyeing of the microfiber nonwoven artificial leather according to claim 1, wherein the soaping process is performed using an anion-type soaping agent, a treatment temperature is 70 to 90 ° C., and a treatment time is 10 to 30 minutes. Way. The method of claim 1, wherein the softening agent treatment step is treated with an anion-type softener, followed by washing and drying.