JPH0674548B2 - Dyeing method for leather-like sheet - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for dyeing a leather-like sheet having a polyamide fiber napped surface. Furthermore, the present invention relates to a dyeing method for obtaining a leather-like sheet having a well dyed surface and having a soft texture.

[Prior Art] Conventionally, there are many proposals for a method for dyeing a fiber sheet made of ultrafine fibers and a fiber-furry leather-like sheet made of a polymer elastic body, but the applicant of the present invention has already proposed equilibrium dyeing in the dip dyeing method. The dyeing method in which the dye is divided and added based on the concentration of the residual dye in the dyeing bath when the condition is reached
In JP-B No. 61-25834 and JP-B No. 61-2834, after dyeing with a dye that becomes water-soluble by being reduced in the presence of an alkali, the dye is made insoluble, and then further dyed with a metal complex salt dye or the like. 46592, JP-A-59-53788, etc.,
A solution prepared by dissolving a dye in a mixed solution consisting of water and an organic solvent miscible with water is applied to the surface and treated with hot water for dyeing in JP-A-57-139583, or a water repellency of 70 or more. JP-A-58-186684 discloses that a water-repellent napped surface is coated with a solution of a dye dissolved in a mixed solution of an organic solvent having a boiling point of 100 ° C. or higher and water, and hot water treatment is performed. Proposed to.

Further, in the production of a suede-like sheet in which a composite sheet composed of a fiber sheet of ultrafine fibers and a polymer elastic body is finished into a suede-like sheet, a specific organic silicon compound is contained in a part of the polymer elastic body to cure or / and It is possible to nap a composite sheet that has been rubberized or treated with a polyorganosilicon compound and dye it with a disperse dye, as disclosed in JP-B-55-32828, JP-B-55-32829, and JP-B-56- It is proposed in Japanese Patent No. 50031, Japanese Patent Publication No. 59-9675 and Japanese Patent Publication No. 59-47072. Furthermore,
An artificial leather having raised fibers of a composite sheet composed of a fiber sheet of ultrafine fibers and a polymer elastic body, wherein an amine or quaternary ammonium salt having at least one alkyl group or alkylaryl group having 8 to 22 carbon atoms at the end of the molecule It is possible to impart a water-repellent effect by treating with a cationic surfactant comprising and to dye.
It is proposed in Japanese Patent Publication No.

[Problems to be Solved by the Invention]

The conventional dyeing method of a fiber-like fur / leather-like sheet has been mainly aimed at eliminating uneven dyeing on the surface, improving dyeing fastness, and improving coloring treatment ability, and improving the napped fiber state. Therefore, the product which achieved the improvement objective is obtained. However, when a leather-like sheet composed of a fiber structure mainly composed of polyamide ultrafine fiber bundle fibers and a polymer mainly composed of polyurethane is dyed with a metal complex dye, the dye remains only on the surface of the sheet, The interior of the sheet is hardly dyed. In such a dyed state, the cutting edge of the sheet looks white, and when sewn, the perforated part looks white, which impairs the product appearance. Therefore, when a leveling agent and a penetrating agent are used to sufficiently dye the inside during dyeing, the texture and feel of the leather-like sheet become strong, resulting in an unfavorable product. Therefore, when a dyeing method using an ordinary acid dye, a disperse dye or a basic dye is taken as a dye, a good dyed product can be obtained, but various fastnesses of the dyed product are low, light resistance, washing resistance, etc. There are drawbacks such as bad.

The present invention is a dyeing method in which a leather-like sheet is dyed with a metal complex salt dye, the surface is dyed in a desired color tone, the inside is dyed lighter than the surface, and the dyeing gradient is small from the surface of the sheet to the center. To provide.

[Means for Solving the Problems]

The present invention dyes a leather-like sheet composed of a fiber structure of fibers mainly composed of polyamide ultrafine fibers and / or bundled fibers thereof and a polymer mainly composed of polyurethane with a dye mainly composed of a metal complex dye. In this case, the dyeing method for a leather-like sheet is characterized in that the material to be dyed is subjected to a water-repellent treatment in the range of 55 to 75 points in water repellency in advance and dyed in an aqueous dye solution at 80 ° C. or higher.

Further, the present invention provides a leather-like sheet to be dyed with the general formula R ₁ CO
NR ₃ (R ₂ NR ₃ ) _n OCR ₁ [wherein R ₁ : an alkyl group having 12 to 28 carbon atoms, R ₂ : an alkylene group having 1 to 4 carbon atoms, R ₃ : H or an intermolecular cross-linking bond, n: [Number of 1 to 8] and treated with a solution or dispersion of a cation activating agent composed of a quaternary ammonium salt obtained by acting, for example, epihalohydrin on fatty acid amide or fatty acid amide, and having a water repellency of 55 to 75 points. The method is a dyeing method for a leather-like sheet, characterized by dyeing in a dye aqueous solution at 80 ° C. or higher with a dye mainly composed of a metal complex dye in the presence of a leveling agent.

That is, a leather-like sheet composed of a fiber structure of fibers having an average fineness of 0.1 denier or less of polyamide ultrafine fibers and / or a bundle of fibers thereof as a main component and a polymer having polyurethane as a main component is made of polyamide. A web obtained by collecting ultrafine fibers spun by the melt blow method. A core-sheath type composite fiber having polyamide as a core and another polymer having a different solubility as polyamide as a sheath component, and another polymer having polyamide as a large number of core components (or island components) and different solubility as polyamide. For example, a polyamide ultrafine fiber bundle-generating multicomponent fiber containing at least one polymer selected from polyethylene, ethylene copolymer, polystyrene, styrene copolymer, polyester, etc. as a sheath component (or sea component), polyamide and polyamide Multi-component fiber in which a large number of other polymers having different physical properties are bonded to each other, and at least one of these polyamide ultrafine fiber-generating multi-component fibers is used as a long fiber or a short fiber by a conventional method. The web is made and the fibrous web is laminated to the required thickness, or laminated with a woven or knitted fabric, and the needle punching method and Or a fiber entangled non-woven fabric by performing entanglement treatment of fibers by a high-pressure fluid flow treatment method, or a woven fabric, knitted fabric, using at least the polyamide ultrafine fiber-generating multi-component fibers for the fibers constituting the fiber raised surface A pile woven fabric and a pile knitted fabric are prepared (the fibrous structure or a fibrous structure made of polyamide ultrafine fibers obtained by treating the fibrous structure is referred to as a fibrous structure). The fiber structure obtained here is treated with a solvent such as a polyamide ultrafine fiber treatment, a decomposing agent treatment, a physical treatment, a mechanical treatment, or the like, or is subjected to a treatment to obtain a polyamide ultrafine fiber or a bundle fiber thereof. After that, the fibrous structure is impregnated with a solution or dispersion of a polymer containing polyurethane as a main component to solidify the polymer into a porous structure or a non-porous structure. If the fiber structure is not a polyamide ultrafine fiber or a bundle thereof, a polyamide ultrafine fiber treatment is performed. Thereby, a base material of a leather-like sheet composed of a fiber structure of fibers mainly composed of polyamide ultrafine fibers and / or bundled fibers thereof and a polymer mainly composed of polyurethane is obtained.

The average fineness of the polyamide ultrafine fibers constituting the leather-like sheet of the present invention is 0.1 denier or less, preferably 0.1 to 0.0005 denier in view of sensory performance such as appearance and texture. It is advantageous to obtain such an ultrafine fiber by spinning an ultrafine fiber-generating multi-component fiber, stretching it into a fiber structure, and then subjecting it to an ultrafine fiber generating treatment. In addition, the polymer mainly composed of polyurethane has an average molecular weight of 500 to 3000.
This is a polyurethane obtained by reacting the polymer diol with an organic diisocyanate and a chain extender, and a synthetic rubber, a vinyl polymer, another elastomer or the like may be added to the polyurethane as required. Further, the ratio of fiber to polymer is preferably in the range of 95/5 to 50/50. In particular, if you want to emphasize the properties of leather, it is better to have a small amount of polymer in the region, and if you want to emphasize the resilience property, you need to have a large amount of polymer. It is a thing.

Next, the base material of the leather-like sheet is sliced to the same thickness as it is or sliced to a required thickness, and at least one surface of the product is buffed with sandpaper, raised with a raising machine, or a combination of both. A leather-like sheet with a surface mainly composed of ultrafine fiber naps of suede-like or nubuck-like finish. The water-repellent treatment of the leather-like sheet is performed after the base material of the leather-like sheet or the surface of the leather-like sheet mainly composed of fine fiber naps. The water repellent treatment shall be in the range of 55 to 75 points of water repellency measured by JIS L-1018. If the water repellency is low, a large amount of the dye solution penetrates into the inside of the sheet, which causes dyeing in a dark color or unevenness of permeation of the dye solution, resulting in an adhesion gradient of the dye. On the other hand, when the water repellency of the sheet is high, the penetration of the dye solution is suppressed and the inside of the sheet is not dyed.

The water repellent used in the present invention is a general fluorine-based water repellent, a silicone water repellent, an alkylmethylolamide type water repellent [general formula R.CONH.CH ₂ OH (where R is a carbon number 11 ~ 25 alkyl groups)], alkyl ethylene urea type water repellents [general formula (Wherein R is an alkyl group having 11 to 25 carbon atoms)], fatty acid amide [general formula R ₁ CONR ₃ (R ₂ NR ₃ ) _n OCR ₁ (wherein R ₁ is an alkyl group having 12 to 28 carbon atoms, R ₂ is an alkyl group having 1 to 4 carbon atoms, R ₃ is H or an intermolecular cross-link bond, n is a number of 1 to 8)] or a cationic activity consisting of a quaternary ammonium salt obtained by acting epihalohydrin on fatty acid amide Agent, pyridinium salt type water repellent [general formula (Wherein R is an alkyl group having 11 to 25 carbon atoms)] and the like, and is a solution or dispersion of at least one water repellent. When a leather-like sheet is treated to be water repellent and then dyed with a dye mainly composed of a metal complex salt dye, the dye distribution inside the sheet is relatively good without hardening the texture of the dyed product. A water repellent having a skeleton of the agent molecule composed of R.CONH- or R.NHCO- is preferable.

Next, the water repellency measured by JIS L-1018 after water repellent treatment 55
A leather-like sheet in the range of -75 points, preferably 60-70 points is dyed with a dye mainly composed of a metal complex salt dye. It is not necessary to use a limited dyeing machine, and a Wins dyeing machine, a Jitzger dyeing machine, a jet dyeing machine, a Pat steam dyeing machine, or the like can be used. As the dye, a 1: 1 type metal complex salt dye or a 1; 2 type metal complex salt dye is used, but the latter dye is preferable. Further, a leveling agent is used in the dye bath, and dyeing is performed at a dye bath temperature of 80 ° C or higher. For the purpose of dyeing only, if the temperature is not higher than 80 ° C., the dye distribution property to the polyamide fiber and polyurethane is good, and a dyed product having relatively good levelness can be obtained. However, in this case, a large amount of dye is dyed inside the sheet, the texture as a leather-like sheet is impaired, and the dyeing fastness becomes poor, so low temperature dyeing is not preferable.

After the dyed leather-like sheet is dried, it is subjected to commercialization finishing such as brushing, styling, rubbing, and addition of various stabilizers.

In the method of the present invention, the surface of the leather-like sheet is dyed in a desired color tone, and the inside of the sheet is dyed with a relatively leveling agent with a dye dyeing amount less than the dye dyeing amount of the surface, and the cut surface of the sheet is cut. A dyed product with a soft, texture-free, non-irritating result is obtained.

〔Example〕

Embodiments of the present invention will be described below with reference to examples. Parts and% in the examples relate to weight unless otherwise specified.

Example 1 An average made by using staple fibers of ultrafine fiber bundle fiber-generating multi-component fibers (hereinafter referred to as multi-component fibers) having a fineness of 5 denier consisting of 50 parts of high-fluidity polyethylene and 50 parts of 6-nylon (island component) 85 parts of a polyester polyurethane in the fiber-entangled nonwoven fabric having a basis weight 600 g / m ^2, a solution prepared by adding polyoxyethylene freezing modifier polyurethane composition comprising a polyurethane 15 parts of a liquid volume of about 200 g / m ² as a polyurethane weight Impregnation, coagulation in a non-solvent type coagulation bath, washing with water, and drying, the resulting sheet is treated in a polyethylene solvent,
Most of the polyethylene component in the fiber was removed, and 6-nylon ultrafine fiber bundle fiber (average ultrafine fiber obtained by microscopic observation
A fiber sheet [I] having a basis weight of about 490 g / m ² containing polyurethane in an entangled nonwoven fabric of 357 fibers / bundle, average fineness of single fiber 0.007 denier was obtained.

The fiber sheet [I] was treated with a silicone water repellent [a composition liquid of Polon MF-8 and Catalyst PA (a product of Shin-Etsu Chemical Co., Ltd.)] at various concentrations and squeezed to a liquid adhesion rate of 70%. , 120 ° C for 5 minutes with a hot air drier to impart water repellency, and then buffing the surface with # 320 sand vapor to form a 1.6mm thick suede-like sheet with a napped fiber surface. Obtained.

This suede-like sheet was dyed under the following conditions.

Brown metal complex salt dye composition 2% owf Leveling agent 2g / l Bath ratio 1:35 Dyeing temperature and time 95 ℃ -60 minutes Dyeing machine Wins dyeing machine Dyeing product obtained by soaping, washing and drying after dyeing It was treated and brushed to obtain a suede-like sheet. Table 1 shows the relationship between water repellency and physical properties of this sheet.

For comparison, Table 1 also shows a suede-like sheet not subjected to the water repellent treatment and a sheet obtained by performing the same dyeing.

As a result, in the sheet without water repellent treatment, the core has a dark color,
Moreover, it was dyed evenly and had a hard texture. On the other hand, when the water repellency is increased, the dye adheres to the surface in a large amount and the surface fluff is hard, and the core is in an undyed state and the cut surface and the sewing perforation appear white and impair the appearance. Not only was it fresh, but it had poor wash fastness. And the product of the present invention is also dyed well in the core,
It had a soft texture and high wash fastness.

Example 2 The fiber sheet [I] of Example 1 is divided into two in the middle of the thickness,
The surface at the time of coagulation was subjected to buffing using # 400 sandpaper to obtain a suede-like sheet having a thickness of 0.8 mm and having a fiber nap surface. This suede-like sheet is treated with an aqueous dispersion of a quaternary ammonium salt of a fatty acid amide with the following basic structure, squeezed to a liquid adhesion rate of 70%, and dried with a hot air dryer at 120 ° C. The water-repellent suede-like sheet obtained by performing the treatment for -5 minutes was dyed under the following conditions.

Black metal complex dye composition 7% owf Leveling agent 0.5g / l Bath ratio 1:40 Dyeing temperature / time 90 ℃ -60 minutes Dyeing machine Wins dyeing machine Dyeing products obtained by soaping, washing and drying after dyeing It was rubbed and brushed to obtain a suede-like sheet. Table 2 shows the relationship between water repellency and physical properties of this sheet.

As a result, the low water repellency has a dark color inside and a hard texture, whereas the dyed products of the examples have a good surface color development, and the interior of the sheet is in a dyed state in which no irritation occurs. Therefore, it had a soft texture and good washing fastness.

[Effects of the Invention] The dyeing method of the present invention is a leather-like sheet having a napped fiber surface, which is dyed in a desired color tone by distributing a large amount of dye on the surface, and the inside of the sheet is relatively even, and is lighter than the surface. A dyed, but non-irritated dyed state is obtained, and a leather-like sheet excellent in flexibility as a leather-like sheet and various dyeing fastnesses and having water repellency can be obtained.

Claims (1)

[Claims] 1. A leather-like sheet composed of a fiber structure mainly composed of polyamide ultrafine fibers and / or bundled fibers thereof and a polymer mainly composed of polyurethane is dyed with a dye mainly composed of a metal complex dye. In this case, a dyeing method for a leather-like sheet, which comprises subjecting an object to be dyed to a water repellency of 55 to 75 points in advance and dyeing the dye in an aqueous dye solution at a temperature of 80 ° C or higher.