JP2786866B2 - Manufacturing method of leather-like sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing a film-like sheet having a silver surface having a soft and firm texture and excellent surface strength.

<Prior Art> Conventionally, there are roughly two methods for producing a leather-like sheet with silver. The first is a method in which a coating layer (surface layer) of an elastic polymer is provided on one surface of a fiber sheet or a fibrous sheet containing an elastic polymer. No. 2 is a fibrous sheet containing an elastic polymer, which is smoothed by hot-melting or press-molding a surface consisting mainly of fiber naps or by applying a solvent or the like to the surface where fibers and polymer are mixed. This is a method of forming a surface. Among the above silver surface forming methods, for the latter method, for example, a solvent or a swelling agent of the substance constituting the fluff is attached to the fluff on the surface of a fibrous sheet containing a polymer substance, and then pressed or Japanese Patent Publication No. Sho 43- (1999) shows that the fluff is glued to the sheet surface by hot pressing, and a polymer coating layer is provided thereon.
No. 25160, Japanese Patent Publication No. 45-14590, the surface of the ultrafine fiber bundle fiber entangled body containing a polymer elastic body is treated with a common solvent of the fiber and the polymer elastic body, and then the surface layer portion Is heated to form a perforated silver surface layer of 30 μ or less by integrating the fiber and the polymer elastic body.
JP-B-48-536, JP-B-48-537, impregnate a sheet-like base material obtained by incorporating a polymer substance into a fiber-entangled nonwoven fabric with a liquid which is a poor solvent for the constituent material of the base material. And forming a surface layer by contact with a heating element
In 19924 publication, one surface of a porous sheet material containing a polymer substance in a fiber aggregate is a surface where fibers and a polymer substance are mixed, and then a polymer substance or And / or embossing roll to which a solvent, a swelling agent or a composition liquid capable of dissolving fibers is applied, and after imparting a surface pattern, the solvent or the swelling agent is removed, and the porous sheet having a surface with an uneven pattern is removed by dyeing. A method for producing such a substance is proposed in Japanese Patent Publication No. Sho 60-12469.

<Problems to be Solved by the Invention> In the conventional silver surface, which is constituted by a porous layer of an elastic polymer, if the influence of the elastic behavior is to be reduced,
If the surface strength is only weak, or if it is composed of a non-porous layer, the surface strength is high, but the elastic behavior is strong,
Difficulty patterning the surface. In addition, it is not only difficult to design the surface of the fused silver surface with mixed fibers, but there are also problems such as a hard texture and poor surface coloring. The silver surface that is present in the form of blood streaks and made by mixing its fibers impairs the appearance, such as color spots due to coloring by dyeing and uneven wrinkles on the surface, and furthermore, surface strength There was a problem that there was a group.

The present invention is a leather having a silver surface excellent in appearance such as surface coloring, wrinkles and the like, which has no blood-streak-like fibrous spots on the surface, is well embossed, and has excellent surface strength, air permeability, and moisture permeability. An object of the present invention is to provide a method of manufacturing a waiting sheet.

<Means for Solving the Problems> The present invention forms an ultrafine fiber napped surface on at least one surface of a sheet-like substrate containing a polymer mainly composed of an elastic polymer in an ultrafine fiber bundle fiber entangled body, The fibers on the fiber raised surface are aligned and temporarily fixed, and a welding or swelling agent mainly containing a solvent for the fibers is applied, and then a press or hot press is performed to join or film-form at least a portion of the fibers on the surface. It is smoothed and then treated in a hot water-based bath containing or not containing a dye, dried, and finished by applying a polymer composition solution containing a colorant to the treated surface of the obtained sheet. This is a method for producing a film-like sheet.

That is, the present invention has a surface mainly composed of ultrafine fibers having an average single fineness of 0.5 denier or less, preferably an average single fineness of 0.2 denier or less, and aligns the surface fibers in one direction to make the surface a silver surface. .

The sheet-like substrate containing a polymer mainly composed of an elastic polymer in the ultrafine fiber bundle fiber entangled body of the present invention is at least two types of thermoplastic polymers having different solubility or degradability with respect to a solvent or a decomposer, for example, The polymer used as the microfiber is polyethylene terephthalate, ethylene terephthalate copolymer, polybutylene terephthalate,
Polyester, 6-nylon, 66-nylon, 61
Polyamides such as 0-nylon, 11-nylon, and the like, polyethylene, polypropylene, and the like, polyolefins, polyvinyl alcohol, at least one polymer selected from the group of the like, and a polymer finally removed are, Combining at least one polymer selected from the group of polyethylene, ethylene copolymer, ethylene vinyl acetate copolymer, polystyrene, styrene copolymer, vinyl chloride copolymer, etc., dissolving removal component or decomposition removal component As the sea component (sheath component or dispersion medium component) and the component used as the ultrafine fiber bundle fiber as the island component (core component or dispersion component). Or joining at least two types of thermoplastic polymers with different physical properties into components that can be divided into multiple pieces It spun into fibers and the fibers obtained by spinning and stretching it necessary, heat fixed, crimped, used as staple fibers or filament fibers of the microfine fiber bundle fiber-forming fibers obtained by cutting. Preferably, staple fibers are used. The fineness of the ultrafine fiber bundle-generating fiber is determined based on the fineness of the ultrafine fiber to be used and the texture of the nonwoven fabric, but is generally in the range of 15 to 1 denier. If the fineness increases, not only a good fiber web cannot be formed, but also the fineness of the ultrafine fibers in one fiber increases, which is not preferable. On the other hand, the fineness of the ultrafine fibers is determined from the surface performance of the leather-like sheet, and the average fineness of the ultrafine fibers is 0.5 denier or less, preferably 0.2 to 0.001 denier. An increase in the fineness of the microfibers forming the surface causes a decrease in the sensory performance of the surface.

And the ultrafine fiber bundle fiber-generating fiber is used alone or other fibers, for example, an acrylic fiber having a fineness of 5 denier or less, a rayon fiber, a recycled fiber such as an acetate fiber,
Fibers selected from plant fibers and the like may be kneaded with the ultrafine fiber bundle fiber-generating fibers as long as the surface performance is not impaired.
The fibers are formed into a fiber web by a wet method or a dry method. Further, the fiber web is laminated according to the desired thickness of the leather-like sheet, and subjected to a fiber entanglement treatment by a needle punch method, a high pressure fluid flow irradiation method, or the like to form a fiber entangled nonwoven fabric.
The basis weight of the fiber-entangled nonwoven fabric or fiber web is determined depending on the thickness of the target product, the amount of the component removed in the fiber, and the like, but is generally in the range of an average fiber basis weight of 1,500 to 100 g / m ² . Further, the fiber entangled nonwoven fabric or fiber web is prepared to contain a polymer. For example, heat treatment, shrinkage treatment, pre-impregnation treatment with glue or resin, surface smoothing treatment, thickness adjustment, two-division treatment in the thickness direction, and, if necessary, ultrafine fiber bundle treatment of fibers. The necessary preparative treatment is carried out to obtain a fiber-entangled nonwoven fabric or a fiber web containing a polymer.

Next, the fiber-entangled nonwoven fabric or the fiber web contains a polymer mainly composed of an elastic polymer. That is, as the elastic polymer, for example, at least one selected from the group of polymer polyols such as polyester polyol, polyether polyol, polyester / polyether block copolymer polyol, polylactone polyol, polycarbonate polyol, and organic polyether Polyurethane, acrylonitrile-butadiene copolymer or acrylonitrile-butadiene-based copolymer, styrene-butadiene copolymer, etc. obtained by a polymerization reaction using isocyanate and a low-molecular compound having two active hydrogen atoms as a chain extender At least one kind of elastic polymer selected from elastic polymers or based on the elastic polymer, and further, if necessary, polybutadiene, polyisoprene, or natural rubber, polyester elastomer, Li amide elastomer composition obtained by blending an elastic polymer selected from such as silicone elastomer, or polyvinyl chloride, vinyl chloride copolymer, a composition containing non-elastomeric polymer selected from the like. For the elastic polymer or the elastic polymer composition, a polymer liquid mainly composed of an elastic polymer dissolved in a solvent or dispersed in a dispersant is prepared. If necessary, an additive selected from a coloring agent, a coagulation regulator, a surfactant, a non-solvent or a solvent, and various stabilizers is added to adjust the polymer liquid. The prepared polymer liquid is impregnated into a fiber-entangled nonwoven fabric or a fiber web. Thereafter, the polymer solvent or dispersant is treated in a non-solvent or solvent-non-solvent solution of the polymer, or dry coagulation in which the solvent or dispersant is removed by treatment with wet heat or dry heat. The method solidifies the polymer in a porous or non-porous manner. The content of the polymer is selected in the range of 90:10 to 40:60 by weight of the fiber: polymer as the final sheet-shaped substrate.

The fiber-entangled nonwoven fabric or fiber web containing the polymer is washed, formed into a fine fiber bundle of fibers, and dried, and a sheet-like substrate containing a polymer mainly composed of an elastic polymer in the fine fiber bundle fiber-entangled body. Get.

The sheet-like base material has at least one surface with a fiber raised surface. That is, the surface of the sheet-like base material is made into a fiber raised surface by buffing treatment with sandpaper, brushing treatment with a needle cloth, and the like, and then the fiber is raised in one direction by combing and brushing. Align. Then, the fibers are temporarily fixed so as not to disturb the aligned fibers. The fiber is temporarily fixed by pressing with a heating roll or a heating plate heated to a temperature at which the fiber is not melted and then heat-set. In this case, a water-soluble substance such as water-soluble starch, polyvinyl alcohol, polyethylene oxide, or the like is used. It is also good to give it. The temporary fixation of the fibers facilitates the next silver surface forming treatment and improves the surface performance.

The sheet-like starting material with the nap fiber surface temporarily fixed is obtained by applying a fiber solvent or swollen rape to the nap fiber surface, and then pressurizing the surface with a press roll or press plate or a heated press roll or press plate. Pressing is performed to bond the fibers on the surface or to form a film and smooth the surface. The solvent or swelling agent to be applied to the fiber surface may be, for example, an alcohol solution of a lithium salt or a calcium salt, benzyl alcohol, phenols, glacial acetic acid or the like for polyamide formation, or nitrobenzene or phenol for polyester. : Toluene, xylene, tetralin, decalin, perchlorethylene, etc. for polyolefins such as ethane tetrachloride mixed solution and m-cresol, and dimethylformamide, dimethylsulfoxide, acetone, 65 for polyacrylic % Potassium thiocyanate solution. The surface coating amount of the solvent or swelling agent is in the range of 3 to ²⁰ g / m ² . If the coating amount is small, there is no effect, but if the coating amount is large, the fibers inside the sheet are joined and the texture hardens,
Not preferred.

The sheet-like material whose surface has been smoothed and shaped like a silver
The treatment is carried out in hot water at 65 to 98 ° C, preferably at a temperature of 75 to 95 ° C. The treatment in hot water consists in removing the treatment agent applied to the sheet-like material and relieving the distortion. It is also preferable to add a dye to the hot water since the sheet can be dyed simultaneously with the treatment. After the hot-water-treated sheet is dried, a solution or dispersion of the polymer composition containing a colorant is applied to the surface having a silver-like surface, and dried in a wet heat or dry heat atmosphere. The surface coating layer is formed by treating the product with a non-solvent. The surface coating polymer weight 2 to 15 g / m ² in solid content is preferably in an amount of 2~7g / m ^2. If the amount of application is large, it becomes similar to that of the conventional leather-like sheet, which is not preferable.

After forming the surface coating layer into a leather-like sheet having a silver surface, if necessary, finish treatment such as surface embossing, kneading, dyeing, softener treatment, water / oiling agent treatment, etc. This is a leather-like sheet product.

The leather-like sheet having a silver surface according to the present invention has excellent uniformity without blood-streak-like fibers on the surface, a large number of fine wrinkles, a natural leather-like profound appearance, and a high surface temperature. It has a soft and stiff texture, and is highly permeable and breathable. This leather-like sheet is for shoes, bags, bags,
Used in natural leather applications such as clothing, apparel, gloves, and upholstery.

<Examples> Next, embodiments of the present invention will be described with specific examples, but the present invention is not limited to these examples.
The parts and percentages in the examples relate to weight unless otherwise specified.

Example 1 A staple fiber obtained by cutting a sea-island type fiber having a fineness of 6 denier of high fluidity polyethylene (sea component) -6-nylon (ultrafine fiber bundle fiber component) to a fiber length of 51 mm was used.
A dry fiber web is made, a laminated web is made by a cross lap method, and a fiber entangled nonwoven fabric is made by a needle punch method, and then heat-treated, impregnated with a dimethylformamide composition liquid containing 13% of a polyester polyurethane and a coagulation controlling agent, Coagulated by treatment in aqueous solution. Then
After washing and squeezing, it is treated in hot perchlorethylene to dissolve and remove the polyethylene in the fibers, and the average number of ultrafine fiber bundles is 400 / bundle, and the average fineness of the ultrafine fibers is 6-nylon ultrafine of 0.008 denier. Fiber bundle entangled nonwoven fabric and porous polyurethane (weight ratio of fiber: polyurethane = 62.2: 37.
8) was obtained. The fibrous sheet is almost at the middle bisection thickness, a thickness of about 0.6 mm, the following average basis weight got two fibrous sheets of 200 g / m ^2, the surface during solidification of the fibrous sheet Buffed with 400-grit sandpaper to form the napped surface of microfibers, brushed the surface with bristle rolls to align the fibers in the regular direction, and heated the surface with a heated calender roll at a surface temperature of 155 ° C. Press processing was performed to temporarily fix the fibers. Next, a methanol solution of 11% calcium chloride was applied to this surface with a gravure roll having a notch of 150 mesh to apply a liquid amount of 20 g / m ² , and then dried with a hot-air dryer at a temperature of 110 ° C.
A sheet having a smooth silver surface to which most of the surface fibers were melt-bonded was obtained. The sheet is treated in a water dyeing machine at a temperature of 90 ° C. for 1 hour to remove calcium chloride and the like, and to relieve the distortion of the sheet. Temperature at the dye liquor
It was dyed at 90 ° C. for 1 hour, soaped, washed with water and dried. Observation of the surface of this sheet-like material with a scanning electron microscope reveals that most of the ultrafine fibers are fused to form a film, but a part remains in a fibrous form, and mainly consists of micropores of 2 to 10μ. Many pores were present on the entire surface. Further, when the cross section was observed, the outermost layer was fused and densified with the fiber, and the welded portion was continuously changed as the fiber became loose inside the base material, which was similar to the cross-sectional structure of natural leather.

Stained sheet is a polyurethane solution prepared by adding pigment brown system, the amount of liquid of about 3 g / m ² by solid content in a gravure machine applied to a surface, dried, then subjected to embossing leather pattern, Further, the leather-like sheet having a silver surface was obtained by performing a buffing process. This leather-like sheet had excellent performance as shown in Table 1.

For comparison, a polyurethane solution containing a brown pigment was applied to the surface of the bisected fiber sheet of Example 1 in such an amount as to give a silvery feel by a gravure machine. The amount is about solid content
19g / m ² was Teatsu. Next, the leather-like sheet obtained by finishing in the same manner as in Example 1 had a large rebound feeling, a small air permeability, and a small moisture permeability.

 The measurement method in Table 1 was as follows.

1) Surface wear is JIS L-0849 method.

 Load: 200g, 500 times, Evaluation: Class 1-No change to Class 5-Torn 2) Air permeability conforms to JIS L-1096, 6.27.2 method.

3) JIS K-6549 method.

<Effect of the Invention> The leather-like sheet having a silver surface of the present invention has a cross-sectional structure with a dense silver surface and a continuous gentle structure toward the inside, and has a soft and stiff texture, It has no fibers, is excellent in smoothness, has many fine wrinkles, has a profound appearance similar to natural leather, and has high surface strength, air permeability and moisture permeability.

Claims (1)

(57) [Claims] An ultrafine fiber bundle entangled body is formed on at least one surface of a sheet-like base material containing a polymer mainly composed of an elastic polymer with a fine fiber raised surface, and the fibers on the fiber raised surface are drawn. After aligning and temporarily fixing, applying a solution or swelling agent mainly composed of a fiber solvent, press or heat press to bond or film and smooth the surface of at least a part of the surface fiber, and then include a dye or A method for producing a film-like sheet, comprising treating in a hot water-based bath containing no dye, drying, and applying a polymer composition solution containing a colorant to the treated surface of the obtained sheet to finish it. .