JPH0742082A - Sheet material having nubuck-like visual appearance and its production - Google Patents

Abstract

PURPOSE:To produce a sheet material exhibiting a visual appearance like that of a nubuck having a soft touch by. preventing a polyurethane resin from penetrating to the back surface of a base fabric and to provide its production method. CONSTITUTION:The back surface of a base fabric is impregnated with an aqueous solution containing a penetrant and the right surface is subjected to raising treatment. This base fabric is coated and impregnated with a non-yellowing type polycarbonate-based polyurethane resin and the polyurethane resin is subsequently subjected to wet coagulation treatment to obtain a sheet material. The resultant sheet material is, as necessary, subjected to embossing finish to form a rugged surface and a raising treatment is subsequently applied thereto, thus producing the objective sheet material having a nubuck-like visual appearance. As the base fabric, a fabric in which the fibers constituting the raised part have <=1 denier single yarn fineness is preferably used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material having a nubuck-like appearance used as a material for furniture, vehicles and the like, and a method for producing the sheet material.

[0002]

2. Description of the Related Art As a sheet material having a nubuck-like appearance (hereinafter sometimes abbreviated as "nubuck-like sheet material"), a polyurethane resin is applied and impregnated on the surface of a fiber base material and wet-solidified. After forming a porous layer, the skin layer on the surface is removed by grinding to expose some of the fine pores, or a raised or napped treatment (hereinafter sometimes abbreviated as "raised" or "raised") A polyurethane resin was applied to the surface of the fiber substrate, impregnated, wet-coagulated to form a porous layer, and then buffed to expose the raised portion of the fiber substrate on the surface.

[0003]

However, since the nubuck-like sheet material as described above is obtained by coating, impregnating, and wet coagulating a polyurethane resin on the surface of a fiber base material, the polyurethane resin is a fiber base material. There has been a problem that the material feels hard because it penetrates into the back surface of the material.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a sheet material having a nubuck-like appearance having a soft texture and a method for producing the sheet material.

[0005]

A sheet material having a nubuck-like appearance is obtained by applying a non-yellowing type polycarbonate-based polyurethane resin onto a fiber base material, impregnating the same, and then wet-coagulating the polyurethane resin. A sheet material having a nubuck-like appearance obtained by raising the surface of the sheet material obtained by the above, wherein the fiber base material is a raised fiber base material, and the back surface is impregnated with an aqueous solution containing a penetrant. It is characterized by being made. Further, the method for producing a sheet material having a nubuck-like appearance according to the present invention comprises applying and impregnating a non-yellowing type polycarbonate-based polyurethane resin on a fiber base material that is raised and impregnated with a penetrant on the back surface. It is characterized in that the surface of a sheet material obtained by wet-coagulating a polyurethane resin in a non-solvent is subjected to embossing to form irregularities and then raised.

The fiber base material used in the present invention is a knitted fabric, woven fabric made of fibers having a single yarn fineness of 1 denier or less, or fiber entanglement provided with an elastic polymer such as polyurethane or synthetic rubber. For example, non-woven fabric. Further, as the fiber constituting the fiber base material, for example, polyester, polyamide,
Synthetic fibers such as polyacrylonitrile, polyolefin, polyvinyl alcohol, etc., chemical fibers such as regenerated cellulose, or multi-component fibers modified into ultrafine fibers by dissolving and removing at least one component or dividing two components be able to.

The above-mentioned fiber base material is sandpaper, sand cloth, sand net, sand roll, needle cloth, grindstone,
Raising is performed by a known method such as a brush. The length and density of the naps at this time are not particularly limited, but generally, the shorter the naps and the higher the density, the more preferable the nubuck-like sheet material can be obtained.

The non-yellowing type polycarbonate-based polyurethane resin used in the present invention is a polymer obtained by reacting a polycarbonate diol with a non-yellowing type diisocyanate and, if necessary, a chain extender.

As the above polycarbonate diol,
It is a polyalkylene polycarbonate diol represented by the general formula shown in the following chemical formula 1, and 1,6-hexane polycarbonate diol is particularly preferably used.

[Chemical 1] (In the formula, p and r are integers of 2 or more, and m is an integer of 5 to 200.) Further, if necessary, a part of the above polyalkylene polycarbonate diol is substituted with a polyalkylene modified carbonate. May be.

The average molecular weight determined from the hydroxyl value of the above polycarbonate diol is in the range of 500 to 5,000, preferably 900 to 3,000. If the molecular weight is less than 500, the concentration of urethane groups will increase, and the flexibility and solvent solubility of the polyurethane resin will decrease. On the other hand, if the molecular weight exceeds 5,000, the urethane group concentration decreases, and the toughness and abrasion resistance peculiar to polyurethane deteriorate.

Examples of the non-yellowing type diisocyanate include tetramethylene diisocyanate and 1,6-
Hexane diisocyanate, 2,2,4-trimethyl-
Aliphatic or alicyclic compounds such as 1,6-hexanediisocyanate, 1-methylcyclohexane-2,4-diisocyanate, 3,3'-dimethyl-4,4'-diisocyanate dicyclohexylmethane and 4,4'-dicyclohexylmethane diisocyanate Can be used. These organic diisocyanates may be used alone or in combination of two or more.

As the chain extender, a compound having two or more active hydrogen atoms, for example, ethylene glycol, propylene glycol, butanediol, hexanediol, 3-methyl-1,5-pentanediol, 1,4-
Cyclohexanediol, diols such as xylylene glycol, ethylenediamine, propylenediamine,
Xylylenediamine, isophorodiamine, piperazine,
Diamines such as phenylenediamine and tolylenediamine, hydrazides such as hydrazine, adipic acid dihydrazide, and isophthalic acid dihydrazide can be used. These chain extenders may be used alone or in combination of two or more.

The non-yellowing type polycarbonate polyurethane resin of the present invention is obtained by reacting the above-mentioned polycarbonate diol, non-yellowing type diisocyanate and chain extender in a desired ratio. As the non-yellowing type polycarbonate-based polyurethane resin, it is preferable to use one having a viscosity of a 20 wt% solution of dimethylformamide in the range of 50 to 150 poise at 25 ° C. Further, the polyurethane resin has a 100% modulus of 10 to 120 kg / cm.
² is preferable. 100% modulus is 10kg /
When it is less than cm ² , the functional strength decreases, and when 100% modulus exceeds 120 kg / cm ² , the texture becomes hard.

The non-yellowing type polycarbonate polyurethane resin which can be used in the present invention is other than the above non-yellowing type polycarbonate polyurethane resin as long as it does not deteriorate the performance such as hydrolysis resistance, light resistance and heat resistance. It is possible to use even a copolymer or a mixture with the above polyurethane resin. Specific examples of the copolymer include a polycaprolactone-polycarbonate copolymer polyurethane resin, a polyester diol-polycarbonate copolymer polyurethane resin obtained by condensation of a diol having 6 or more carbon atoms and a dicarboxylic acid, and the like. Examples of the polyurethane that can be mixed with the modified polycarbonate polyurethane resin include polycaprolactone polyurethane resin, polytetramethylene glycol polyurethane resin, and polyester polyurethane resin obtained by condensation of diol having 6 or more carbon atoms and dicarboxylic acid. .

The yellowing-free type polycarbonate polyurethane resin described above may be mixed with various additives such as a coagulation regulator (surfactant), a colorant, a filler, an antioxidant, a water repellent, and an oil repellent, if necessary. Then, a polyurethane resin solution having an appropriate concentration is prepared using a solvent such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and dimethylsulfoxide. The polyurethane resin content at this time cannot be unconditionally specified because it depends on the purpose and application, but is generally 2 to 30% by weight based on the fiber base material. Further, collagen powder or the like may be added to the non-yellowing type polycarbonate-based polyurethane resin solution, if necessary.

The penetrant used in the present invention includes aerosol OH type (ie, sodium salt of di-2-ethylhexyl sulfosuccinate), sodium dodecylbenzenesulfonate, sodium lauryl sulfate ester, butyl oleate sulfate ester, and alkyl ester. Anionic systems such as sodium naphthalene sulfonate, nonylphenol ethylene oxide adducts, octylphenol ethylene oxide adducts, non-ionic systems such as intermediate to higher alcohol ethylene oxide adducts and the like can be used.

The penetrant is impregnated into the back surface of the fiber base material as an aqueous solution of about 0.1 to 5%. At this time, the amount of the penetrating agent aqueous solution attached to the fiber base material is 5
It is about 30% by weight. Further, as a method for applying the penetrant aqueous solution to the back surface of the fiber base material, a known method such as a spray method or a backsizing method using a mesh roll is adopted and is not particularly limited.

The above-mentioned polycarbonate-based polyurethane resin solution is applied by a means such as a doctor knife onto a fiber substrate whose back surface is impregnated with an aqueous penetrant solution, and thereafter,
The coated part is immersed in water or a non-solvent such as an aqueous solution of the above-mentioned polyurethane resin solvent to coagulate and desolvate the polyurethane resin, then washed with water and dried to obtain a sheet. The non-solvent used at this time is 0 of dimethylformamide.
A ~ 20% aqueous solution is especially preferred. Further, the solidification temperature of the polycarbonate-based polyurethane resin may be appropriately selected within the range of 15 to 40 ° C.

The sheet-like material on which the polycarbonate-based polyurethane resin layer is formed is embossed with a embossing roll or the like, if necessary, to have irregularities on the surface, and then raised. As a method for raising hair at this time, the same method as the above-described raising method for fiber base material can be used, but not so strong conditions, using sandpaper or a brush having a gentle grinding action. It is preferable to lightly brush the hair.

Further, without uniformly raising the entire surface,
If the fiber-raised part is a surface in which almost no fiber-raised part is mixed, that is, the fiber-raised part and the non-fiber-raised part are not clearly separated and are mixed together as a unit, they are more natural. A nubuck-like sheet similar to leather can be obtained. Further, the nubuck tone sheet of the present invention can be subjected to usual dyeing treatment and rubbing treatment at any stage of the above steps.

[0021]

The nubuck-like sheet obtained by the present invention has the back surface of the fiber base material impregnated with the penetrant aqueous solution, so that the polycarbonate polyurethane resin is prevented from seeping into the back surface side of the fiber. It is possible to obtain a soft nubuck-like sheet. Further, since the polyurethane resin does not seep out to the back surface side of the fiber base material, the appearance of the back surface side of the obtained nubuck tone sheet is improved.

[0022]

EXAMPLES The present invention will be described in more detail with reference to specific examples.

Example 1 A polyester fiber made of high multifilament having a single yarn fineness of 0.4 denier in the front and a polyester fiber made of multifilament having a single yarn fineness of 2 denier in the middle and back are knitted in a warp knit. 0.5% sodium dodecylbenzenesulfonate on the back side of the fiber substrate having a 0.75 mm thick single-sided brush dyed gray
After impregnating the aqueous solution containing 60% by weight with a 60-mesh mesh roll, a non-yellowing type polycarbonate-based polyurethane resin solution having the composition shown in Table 1 was formed on the raised surface of the fiber substrate with a knife coater. , Polyurethane solid content was 30 g / m ² (polyurethane adhesion amount was about 10.3% with respect to the fiber substrate), and then the fiber substrate was coated with a 13% dimethylformamide aqueous solution (liquid temperature 20 ° C.). ), To solidify the polyurethane resin, and then to remove the solvent in warm water at 60 ° C., wash and dry to obtain a sheet-like product having a polyurethane resin layer on the surface. The obtained sheet-like material had a thickness of 0.85 mm, had no strike-through or exudation of the polyurethane resin, had a soft texture, and had excellent flexibility.

[0024]

[Table 1] Resamine CNU650-20 ^{* 1} 100 parts by weight Dimethylformamide 65 parts by weight Colorant 15 parts by weight Coagulation regulator 2 parts by weight * 1 Dainichiseika Co., Ltd. (NV 20%, 100% modulus 60 kg / m ² )

The surface of the obtained sheet-like material is subjected to heat and pressure embossing with an embossing roll having a leather pattern,
The surface was lightly buffed with a 240 mesh sandpaper to obtain a nubuck-like sheet having a thickness of 0.65 mm. The obtained nubuck-like sheet has a soft texture, excellent flexibility, a moist feel and a smooth and natural touch similar to natural leather, and the nubuck appearance and touch of natural leather is very high. It was an approximation. Further, the obtained nubuck-like sheet was excellent in hydrolysis resistance, light resistance and heat resistance, and was suitable as a sheet for furniture and vehicles.

Example 2 A polyester fiber composed of a multifilament having a single yarn fineness of 0.6 denier in the front and a polyester fiber composed of a multifilament having a single yarn fineness of 2 denier in the middle and the back are knitted in a warp knit, On the back surface of the fiber substrate having a 0.85 mm thick single-sided brush dyed brown,
An aqueous solution containing 1.0% by weight of sodium di-2-ethylhexyl sulfosuccinate was impregnated with a mesh roll of 60 mesh, and then the composition shown in Table 2 with a knife coater on the raised surface of the fiber base material. A non-yellowing type polycarbonate-based polyurethane resin solution consisting of the above is applied so that the polyurethane solid content is 40 g / m ² (the polyurethane adhesion amount is about 12.9% with respect to the fiber base material), and then the fiber is applied. Base material is dimethylformamide 1
A sheet material having a polyurethane resin layer on the surface after being immersed in a 3% aqueous solution (liquid temperature 20 ° C.) to solidify the polyurethane resin, desolvated in warm water at 60 ° C., washed and dried. Got The obtained sheet material has a thickness of 0.9 mm.
There was no strike-through or bleeding out of the polyurethane resin, the texture was soft and the flexibility was excellent.

[0027]

[Table 2] Crisbon MP-303 ^{* 2} 100 parts by weight Dimethylformamide 60 parts by weight Colorant 15 parts by weight Coagulation regulator 2 parts by weight * 2 Manufactured by Dainippon Ink and Chemicals (NV 20%, 100% modulus 45 kg / m ² )

The surface of the obtained sheet-like material was subjected to heat and pressure embossing with an embossing roll having a pore-drawing pattern, and then the surface was lightly buffed with 240 mesh sandpaper to obtain a thickness of 0. A 65 mm nubuck-like sheet was obtained. The obtained nubuck-like sheet has a soft texture, excellent flexibility, a moist feel and a smooth and natural touch similar to natural leather, and the nubuck appearance and touch of natural leather is very high. It was an approximation. The obtained nubuck-like sheet was excellent in hydrolysis resistance, light resistance, and heat resistance, and was suitable as a sheet material for furniture and vehicles.

Comparative Example 1 A nubuck tone sheet was obtained in the same manner as in Example 1 except that the aqueous sodium dodecylbenzenesulfonate solution was not impregnated. The obtained sheet material had a polyurethane resin through the entire back surface of the substrate, had bleeding, had a hard texture, and was inferior in flexibility.

Comparative Example 2 A nubuck tone sheet was obtained in the same manner as in Example 1 except that the aqueous sodium di-2-ethylhexyl sulfosuccinate solution was not impregnated. The obtained sheet material had a polyurethane resin through the entire back surface of the substrate, had bleeding, had a hard texture, and was inferior in flexibility.

Comparative Example 3 A nubuck tone sheet was obtained in the same manner as in Example 1 except that water containing no sodium dodecylbenzenesulfonate was impregnated. The obtained sheet material had a polyurethane resin through the entire back surface of the substrate, had bleeding, had a hard texture, and was inferior in flexibility.

[0032]

The nubuck-like sheet obtained by the present invention is
It is soft to the touch and excellent in flexibility, and has an excellent aesthetic appearance in which the polyurethane resin does not seep out to the back surface side of the fiber base material. Further, since a non-yellowing type polycarbonate-based polyurethane resin is used as the polyurethane-based resin, it has excellent hydrolysis resistance, light resistance, and heat resistance, and can be suitably used as a seat material for furniture and vehicles.

Claims (4)

[Claims] 1. A non-yellowing type polycarbonate-based polyurethane resin is applied and impregnated on a fiber base material, and the surface of a sheet material obtained by wet coagulating the polyurethane resin is napped. A sheet material having a nubuck-like appearance, wherein the fibrous base material is a raised fibrous base material, and the back surface is impregnated with an aqueous solution containing a penetrant. Sheet material having. 2. The sheet material having a nubuck-like appearance according to claim 1, wherein the fiber constituting the raised portion of the fiber base material subjected to the raising treatment has a fineness of 1 denier or less. 3. A sheet material having a nubuck-like appearance according to claim 1, wherein surface irregularities are formed by embossing before the surface of the non-yellowing type polycarbonate-based polyurethane resin layer is raised. . 4. A non-yellowing type polycarbonate type resin is applied and impregnated on a fiber substrate which has been raised and has a back surface impregnated with a penetrant, which is impregnated and impregnated in a non-solvent. A method for producing a sheet material having a nubuck-like appearance, which comprises subjecting a surface of a sheet material obtained by wet-coagulating a polyurethane resin to embossing to form irregularities, and then performing a raising treatment.