JP3015131B2 - Leather-like sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a leather-like sheet. More specifically, the present invention relates to a leather-like sheet comprising a polyurethane resin containing a polyurethane elastomer containing a polyester polyol component and a polycarbonate polyol component having a specific structure as essential components, and a fiber substrate.

The leather-like sheet material of the present invention has a unique feeling such as a slimy feeling and is excellent in durability, so that it can be used for ordinary synthetic leather and artificial leather. It is applicable, for example, useful as a material for shoes, bags, bags, clothing, and the like.

[0003]

2. Description of the Related Art As leather-like sheets made of a fiber base and a polyurethane resin, various synthetic leathers and artificial leathers having a so-called silver or suede tone have been known.

Japanese Patent Application Laid-Open No. 2-33384 discloses a flexible polyurethane material obtained by reacting a polycarbonate polyol containing a 2-methyl-1,8-octanediol unit with an organic diisocyanate as a skin material. It is described that a synthetic leather having good resistance and hydrolysis resistance can be produced.

On the other hand, it has been proposed to use a poly (3-methylpentamethylene adipate) polyurethane resin as a polyurethane resin used for a leather-like sheet. That is, JP-A-61-207675 discloses a polymer diol mainly composed of poly (3-methylpentamethylene adipate) diol, 4,4 '.
-Describes that a leather-like sheet produced by a wet coagulation method using a polyurethane obtained by reacting diphenylmethane diisocyanate and a low-molecular diol has excellent hydrolysis resistance and surface smoothness, and has a soft feel. According to the publication, in the production of polyurethane, if a polymer diol other than poly (3-methylpentamethylene adipate) diol such as polyethylene glycol is used in an amount of about 15% by weight or less of the total polymer diol, poly ( (3-methylpentamethylene adipate) diol.

[0006]

In recent years, there has been a remarkable trend in the trend toward higher-grade consumerism and the emphasis on sensibility and fashion, and even in leather-like sheet materials such as synthetic leather and artificial leather. Demands for unrequested properties are becoming more stringent.
The inventors of the present invention have examined the sliminess of a leather-like sheet, and found that 2-methyl-1,8-octanediol unit as described in JP-A-2-33384 is used. From the polycarbonate-based polyurethane obtained by reacting the contained polycarbonate-based polyol with an organic diisocyanate, it was found that a leather-like sheet having a good slimy feeling could not be obtained.

Further, a poly (3-methylpentamethylene adipate) diol or a mixed polymer diol having a weight ratio of 90 to 10 with other polymer diols described in JP-A-61-207675 is used. From the polyurethane obtained by reacting with 4,4'-diphenylmethane diisocyanate and a low molecular weight diol, it was found that a leather-like sheet having a good slimy feeling could not be obtained.

SUMMARY OF THE INVENTION An object of the present invention is to provide a leather-like sheet made of a fiber base and a polyurethane resin, which has a good slickness and is accompanied by deterioration of the good slickness over time. The object of the present invention is to provide a leather-like sheet having excellent durability.

[0009]

According to the present invention, an object of the present invention is to provide a leather-like sheet comprising a fiber substrate and a polyurethane resin, wherein the polyurethane resin is
(A) a polyester-based polyol containing an alkanediol unit having 5 to 6 carbon atoms derived from 1,5-pentanediol which may be substituted with a methyl group and a dicarboxylic acid unit, and a polyester-based polyol which is substituted with a methyl group Good 1,8
Alkanediol units having 8 to 10 carbon atoms derived from at least one alkanediol selected from the group consisting of -octanediol and 1,9-nonanediol;

[0010]

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A polymer polyol consisting essentially of a polycarbonate polyol consisting essentially of a carbonyl unit represented by the formula: wherein the weight ratio of the polyester polyol to the polycarbonate polyol is in the range of 5:95 to 80:20; It is achieved by providing a leather-like sheet comprising a polyurethane elastomer obtained by reacting with an organic diisocyanate.

The above-mentioned polyester polyol which is one of the essential components of the polymer polyol in the present invention [hereinafter referred to as polyester polyol (A-1)].
Has the above-mentioned specific alkanediol unit and dicarboxylic acid unit as essential constitutional units, and has an average of about 2 alcoholic hydroxyl groups at the molecular chain terminals.

The above specific alkanediol unit, which is one of the essential structural units of the polyester-based polyol (A-1), may be substituted with one methyl group.
From 5-pentanediol, 2 contained in two hydroxyl groups
Units (hereinafter, such units are referred to as alkanediol units (I)) excluding a number of hydrogen atoms, and represented by the general formula:

[0014]

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(Wherein, R represents a hydrogen atom or a methyl group, m represents an integer of 0 to 2, n represents an integer of 2 to 4, wherein the sum of m and n is 4) To). The alkanediol unit (I) has the formula

[0016]

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The leather-like sheet obtained is 3-methyl-1,5-pentanediol unit (hereinafter referred to as MPD unit) which is particularly excellent in slimy feeling and durability, and It is possible to produce a soft leather-like sheet material with uniform fine pores in the polyurethane resin phase when using the wet method due to the good coagulability of the polyurethane elastomer in non-solvents. Is desirable.

The polyester-based polyol (A-1) may contain one or more diol units other than the alkanediol unit (I). Such diol units include:
For example, ethylene glycol, propylene glycol,
1,4-butanediol, 1,6-hexanediol,
Saturated aliphatic diols such as 1,9-nonanediol, 2-methyl-1,8-octanediol, neopentyl glycol; saturated alicyclic diols such as 1,4-cyclohexanediol; divalent such as xylylene glycol Examples include units in which two hydrogen atoms contained in two hydroxyl groups are removed from a diol such as an aromatic alcohol.
The content of the diol unit other than the alkanediol unit (I) is not particularly limited as long as the action and effect of the present invention are not impaired, but generally, the total content contained in the polyester-based polyol (A-1) is not limited. 4 per diol unit
0 mol% or less, and the sum of the product of the mole fraction of each diol unit contained in the polyester-based polyol (A-1) with respect to all diol units and the number of carbon atoms of each diol unit is 5.0 or more. That is, the expression

[0019]

(Equation 1)

(Where k represents the number of types of diol units contained in the polyester polyol, and Xi represents the i-th diol unit.
Represents the number of carbon atoms of the diol unit of the i-th kind, and Mi represents the mole fraction of the diol unit of the i-th kind with respect to all the diol units contained in the polyester-based polyol. It is preferable that it is within the range.

The type of the dicarboxylic acid unit constituting the polyester-based polyol (A-1) is not particularly limited, and may be any dicarboxylic acid unit constituting the polyester-based polyol used in the production of ordinary polyurethane. I just need. Such dicarboxylic acid units include, for example, two dicarboxylic acids such as saturated aliphatic dicarboxylic acids such as adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid; and dicarboxylic acids such as aromatic dicarboxylic acids such as isophthalic acid and terephthalic acid. Examples of the unit include a unit in which two hydroxyl groups in a carboxyl group are removed. Of these dicarboxylic acid units, adipic acid units, azelaic acid units, sebacic acid units, etc. Is desirable. In addition, the dicarboxylic acid unit which comprises the polyester-type polyol (A-1) may be only one type, and may be two or more types.

The polyester polyol (A-1) is
As described above, it is substantially composed of a diol unit containing at least one type of alkanediol unit (I) and a dicarboxylic acid unit, but other small amounts within a range not impairing the action and effect of the present invention. Units may be included.
Examples of such optional units include tri- or higher-valent units obtained by removing a hydrogen atom in a hydroxyl group from a tri- or higher-valent polyhydric alcohol such as glycerin, pentaerythritol, and trimethylolpropane.

The molecular weight of the polyester-based polyol (A-1) is not particularly limited, but the molecular weight range of the polyester-based polyol used as a usual raw material for producing polyurethane is preferably employed. . In particular, when the number average molecular weight is from 500 to 10,000, particularly from 800 to 5,000, the handleability of the polyether polyol (A-1) and the polyurethane elastomer obtained therefrom becomes good, and the slimy feeling of the obtained leather-like sheet material is obtained. In addition, the durability is generally particularly preferable in all cases.

The method for producing the polyester polyol (A-1) in the present invention is not particularly limited, and known polyester production means can be applied.
For example, the polyester-based polyol (A-1) is a diol having a structure corresponding to a desired diol unit and a dicarboxylic acid having a structure corresponding to a desired dicarboxylic acid unit or an ester-forming derivative thereof such as a methyl ester or an ethyl ester. Is esterified or transesterified at 150-250 ° C. in the presence of an esterification catalyst and / or a transesterification catalyst in the desired proportion, and the resulting reaction product is then reduced under reduced pressure to 200-3
It can be produced by condensation polymerization at 00 ° C.

The above-mentioned polycarbonate-based polyol (hereinafter referred to as polycarbonate-based polyol (A-2)), which is one of the essential components of the polymer polyol in the present invention, comprises the above-mentioned specific alkanediol unit and carbonyl unit as essential components. It has as a unit, and has about two alcoholic hydroxyl groups on the molecular chain terminal on average. The above specific alkanediol unit, which is one of the essential structural units of the polycarbonate-based polyol (A-2), comprises a 1,8-octanediol and a 1,9-nonanediol which may be substituted with a methyl group. A unit obtained by removing two hydrogen atoms contained in two hydroxyl groups from at least one alkanediol having 8 to 10 carbon atoms selected from the group consisting of [alkanediol unit (II)
And the general formula

[0026]

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(Wherein R represents a hydrogen atom or a methyl group, m and n each represent an integer of 0 or more, and the sum of m and n is 7 or 8). The alkanediol unit (II) has the formula

[0028]

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A 2-methyl-1,8-octanediol unit (hereinafter referred to as a MOD unit) represented by the formula:

[0030]

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The 1,9-nonanediol unit (hereinafter, referred to as ND unit) represented by the following formula (1) is desirable because the leather-like sheet obtained is particularly excellent in sliminess and durability.

The MOD unit and the ND unit which may be contained in the alkanediol unit (II) may be only one of them, or both.
It contains both ND units and MOD units as alkanediol units (II), and the molar ratio of ND units to MOD units is in the range of 90/10 to 10/90, especially 80/2
It is desirable to be within the range of 0 to 20/80, since the resulting leather-like sheet gives a leather-like sheet having particularly good sliminess and durability.

Polycarbonate polyol (A-2)
May contain one or more diol units other than the alkanediol unit (II). Such diol units include, for example, alkanediols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol; A cycloalkanediol such as cyclohexanediol; a unit in which two hydrogen atoms contained in two hydroxyl groups are removed from a diol such as a divalent aromatic alcohol such as xylylene glycol. The content of the diol unit other than the alkanediol unit (II) is not particularly limited as long as the action and effect of the present invention are not impaired, but generally the polycarbonate polyol (A-2)
It is desirably 40 mol% or less based on all diol units contained therein.

Polycarbonate polyol (A-2)
Is substantially composed of a diol unit containing at least one alkanediol unit (II) as described above and a carbonyl unit, but in a small amount within a range that does not impair the action and effect of the present invention. , And other structural units. Examples of the constituent units which may be optionally contained include, for example, trivalent or higher-valent units in which hydrogen atoms in hydroxyl groups are removed from trivalent or higher-valent alcohols such as glycerin, pentaerythritol, and trimethylolpropane. .

Polycarbonate polyol (A-2)
Although the molecular weight of is not particularly limited, a range of the molecular weight of a polycarbonate diol such as poly (hexylene carbonate) diol used as a usual raw material for producing polyurethane is preferably employed. Among them, the number average molecular weight is in the range of 500 to 10000, especially in the range of 800 to 5000,
The polycarbonate-based polyol (A-2) and the polyurethane obtained therefrom have good handleability, and the resulting leather-like sheet-like material often has particularly good slickness and durability, and thus is generally used. Preferred.

The method for producing the polycarbonate polyol (A-2) in the present invention is not particularly limited, and any known polycarbonate production means can be applied. For example, a polycarbonate-based polyol (A-
2) using a diol having a structure corresponding to a desired diol unit and a carbonate ester such as an alkylene carbonate such as ethylene carbonate, a diaryl carbonate such as diphenyl carbonate, a dialkyl carbonate such as diethyl carbonate or dimethyl carbonate in a desired ratio. Or by using the diol and phosgene in a desired ratio.

In the present invention, in order to produce a polyurethane elastomer, the polyester polyol (A-1) and the polycarbonate polyol (A-2) are used as polymer polyols in a range of 5:95 to 80:20. It is essential to use them together in a weight ratio. When the weight ratio between the polyester polyol (A-1) and the polycarbonate polyol (A-2) in the polymer polyol is out of the above range, a leather-like sheet having a good slimy feeling cannot be obtained. Polyester polyol (A-1) and polycarbonate polyol (A-2)
Is preferably in the range of 20:80 to 70:30, since the slimy feeling and durability of the obtained leather-like sheet material are particularly good.

In the present invention, other polymer polyols may be used as the polymer polyol together with the essential polymer polyols such as the polyester polyol (A-1) and the polycarbonate polyol (A-2) described above. . Examples of the polymer polyol that may be optionally used include polyester polyols other than the polyester polyol (A-1); poly (ε-caprolactone) polyol, poly (β-methyl-δ-valerolactone) polyol, and the like. Polylactone-based polyols; polyether-based polyols such as polyoxypropylene polyol and polyoxytetramethylene polyol; and polycarbonate-based polyols other than the polycarbonate-based polyol (A-2) such as poly (hexylene carbonate) polyol.

The polyester polyols which may be optionally used include, for example, ethylene glycol,
Propylene glycol, 1,4-butanediol, 1,
6-hexanediol, 1,9-nonanediol, 2-
At least one diol such as methyl-1,8-octanediol, 1,4-cyclohexanediol, xylylene glycol, neopentyl glycol, and adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, isophthalic acid, terephthalic acid Examples include condensation polymers with at least one aliphatic or aromatic dicarboxylic acid such as an acid. The amount of the polymer polyol that may be used arbitrarily is not particularly limited as long as the action and effect of the present invention are not impaired, but it is 50% by weight or less based on the total amount of the polymer polyol used. However, the resulting leather-like sheet-like material is generally preferred because its slimy feeling and its durability and other properties are often particularly good.

In the present invention, the organic diisocyanate used for producing the polyurethane elastomer may be any organic diisocyanate used for producing ordinary polyurethane. Examples of such organic diisocyanates include aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, and xylylene diisocyanate; hexamethylene diisocyanate, isophorone diisocyanate, and 4,4'-
Examples thereof include aliphatic or alicyclic diisocyanates such as dicyclohexylmethane diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated xylylene diisocyanate. Among these organic diisocyanates, 4,4′-diphenylmethane diisocyanate, tolylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, etc. are particularly advantageous for industrial use because of their high versatility. .

In the present invention, in order to produce a polyurethane elastomer, a polymer polyol and an organic diisocyanate are used as essential raw materials, but if desired, a chain extender may be used in combination. Such a chain extender may be any one as long as it is used for the production of ordinary polyurethane, and a low molecular weight compound having a molecular weight of 400 or less having two or more active hydrogen atoms in the molecule is usually used. used. Representative examples of such low molecular weight compounds include ethylene glycol, propylene glycol,
4-butanediol, 1,6-hexanediol, 3-
Aliphatic diols such as methyl-1,5-pentanediol, 1,9-nonanediol and 2-methyl-1,8-octanediol; alicyclic diols such as 1,4-cyclohexanediol; xylylene glycol; Dihydric aromatic alcohols; polyalkylene glycols such as diethylene glycol, dipropylene glycol, dibutylene glycol, triethylene glycol, and tripropylene glycol; diols such as carboxylic acid-containing diols such as dimethylolpropionic acid; ethylenediamine, propylenediamine; Aliphatic, alicyclic or aromatic diamines such as xylylenediamine, isophoronediamine, phenylenediamine and tolylenediamine; heterocyclic compounds containing two imino groups in a cyclic structure such as piperazine; Phosphate dihydrazide, dihydrazide such as isophthalic acid dihydrazide; hydrazine; trimethylolpropane, pentaerythritol, and the like trihydric or higher alcohols, such as glycerin. Examples of the chain extender include at least one of the above-mentioned diols, diamines, heterocyclic compounds having two imino groups in a cyclic structure, low-molecular compounds having two active hydrogen atoms in the molecule, such as dihydrazide and hydrazine. One kind alone or the above 3
It is general to use in combination with at least one of the alcohols having a valency or higher.

A polyurethane elastomer obtained by reacting a polymer polyol comprising a polyester polyol (A-1) and a polycarbonate polyol (A-2) with an organic diisocyanate and, if necessary, a chain extender [hereinafter referred to as polyurethane elastomer (E) )]
The solution viscosity of is not particularly limited,
The passability of the leather-like sheet during the manufacturing process is good, and the slimy feeling and durability of the obtained leather-like sheet are often particularly good.
The viscosity of a solution having a solid content concentration of 25% by weight in dimethylformamide solvent measured at 5 to 200 poise,
It is generally preferred that it be between 0 and 900 poise.

With respect to a specific operation method for producing the polyurethane elastomer (E), a known technique of a urethane reaction is used. For example, a polymer polyol such as the above-mentioned polyester-based polyol (A-1) and polycarbonate-based polyol (A-2) and, if necessary, a chain extender are mixed, preheated to about 40 to 100 ° C., and then an organic diisocyanate is added. The reaction is carried out at 50 to 140 ° C. for several hours, and if necessary, the same or different type of chain extender already used is mixed and reacted at 20 to 140 ° C. for several hours to obtain a desired polyurethane elastomer. . In the urethanization reaction, a normal urethanization reaction catalyst, for example, an organic tin compound, an organic titanium compound, a tertiary amine, or the like may be used, if desired. Further, the above reaction may be performed in the presence of an organic solvent inert to the organic diisocyanate. Examples of the organic solvent include aromatic hydrocarbons such as toluene; esters such as ethyl acetate; amides such as dimethylformamide;
Ketones such as methyl ethyl ketone, methyl isobutyl ketone and acetone; cyclic ethers such as tetrahydrofuran; halogenated hydrocarbons such as trichloroethylene and the like are used alone or in an arbitrary mixture. These exemplified organic solvents are isopropanol, ethanol,
You may mix and use with alcohols, such as methanol.
When the reaction is performed in the presence of an organic solvent, the solid content at the end of the reaction is 5 to 90% by weight, preferably 10 to 6% by weight.
In general, the amount of the organic solvent used is adjusted to be 0% by weight.

The polyurethane elastomer (E) obtained as described above is used alone or in a mixture with a polyurethane elastomer other than the polyurethane elastomer (E) to constitute the leather-like sheet of the present invention together with the fiber base. It is used as a polyurethane resin. As the polyurethane elastomer which can be optionally used in combination with the polyurethane elastomer (E), a usual polyurethane elastomer used together with a fiber base for producing a usual artificial leather or a synthetic leather can be used. Representative examples of such polyurethane elastomers that may optionally be used include ethylene glycol, propylene glycol, 1,4-butanediol,
1,6-hexanediol, 1,9-nonanediol,
At least one low molecular weight diol such as 2-methyl-1,8-octanediol, 1,4-cyclohexanediol, xylylene glycol, neopentyl glycol, and adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid; Polyester polyol such as polycondensate with at least one aliphatic or aromatic dicarboxylic acid such as isophthalic acid and terephthalic acid; polyether polyol such as polyoxypropylene polyol and polyoxytetramethylene polyol; poly Polylactone polyols such as (ε-caprolactone) polyol and poly (β-methyl-δ-valerolactone) polyol; polymer polyols such as polycarbonate polyol such as poly (hexylene carbonate) polyol; Polyurethane elastomer obtained by urethanization by a conventional method using a chain extender, if necessary with the cyanate and the like. The amount of the polyurethane elastomer that may be used arbitrarily is not particularly limited as long as the action and effect of the present invention are not impaired, but the polyurethane constituting the leather-like sheet material of the present invention together with the fiber base is not limited. It is generally preferred that the content be 50% by weight or less based on the total amount of the system resin, since both the slimy feeling and the durability of the obtained leather-like sheet material are particularly good in many cases.

The fibrous base material constituting the leather-like sheet of the present invention may be a two-dimensional fiber aggregate such as a woven fabric, a knitted fabric, or a non-woven fabric, which is used for producing ordinary synthetic leather and artificial leather. It is a three-dimensional fiber assembly. Examples of the fiber constituting the fiber base include natural fibers such as cotton, hemp, and wool; regenerated fibers such as viscose rayon fiber and copper ammonia rayon fiber; semi-synthetic fibers such as acetate fiber; polyamide fibers (nylon 6 fiber, nylon 66 fiber). Fiber, aromatic nylon fiber, etc.), polyvinyl alcohol fiber, polyvinylidene chloride fiber, polyester fiber, polyacrylonitrile fiber, polyurethane fiber, synthetic fiber such as poly (alkylene paraoxybenzoate) fiber, etc. Among them, cotton, polyamide fiber (nylon 6 fiber, nylon 66 fiber, aromatic nylon fiber, etc.), polyvinyl alcohol fiber,
Polyester fiber, polyurethane fiber and the like are preferably used. These fibers may be ordinary fibers or specially-shaped fibers such as fine fibers and porous fibers. In addition, the fiber substrate may be obtained by impregnating the above-mentioned fiber aggregate with an elastic polymer such as a polyurethane elastomer other than the polyurethane elastomer (E).

The leather-like sheet material of the present invention is in a so-called silvery or polymer suede-like form in which a layer of a polyurethane resin is coated on a fiber substrate, and the polyurethane resin is impregnated in the fiber substrate. Any of so-called fibrous suede-like forms. In a leather-like sheet having a form in which a polyurethane resin layer is coated on a fiber substrate, an adhesive layer and / or an adhesive layer and / or a polyurethane resin (E) -containing polyurethane resin layer are provided between the layer and the fiber substrate. Alternatively, a mesothelial layer may be interposed. As the resin constituting the adhesive layer or the intermediate layer, for example, polyurethane is preferably employed. Various additives such as those used in ordinary synthetic leather or artificial leather can be blended with the polyurethane resin containing the polyurethane elastomer (E) depending on the purpose of use of the leather-like sheet. . Examples of such additives include coloring agents such as pigments and dyes, inorganic fillers, concealing agents, softeners, antioxidants, ultraviolet absorbers, surfactants, coagulation regulators, lubricants, and the like.

The leather-like sheet of the present invention can be produced by a known method such as a wet method or a dry method, which is employed for producing ordinary synthetic leather and artificial leather. Can be manufactured. As a method for producing a leather-like sheet by the dry method, for example, the following transfer method can be adopted. First, a solution of a polyurethane-based resin containing a polyurethane elastomer (E) is applied on release paper with a doctor knife, and 90 to 11
By drying with hot air at 0 ° C. for 2 to 3 minutes, a resin layer for skin is formed on release paper. A resin solution for an adhesive such as polyurethane is applied on the resin layer on the release paper, and a fiber substrate is further laminated thereon using a laminating roll, and dried with hot air at 90 to 110 ° C. for 2 to 3 minutes. I do. Next, the obtained laminate is heated at 40 to 60 ° C. for 2 to 2 hours.
After aging for 3 days, the release paper is peeled off, and if necessary, the surface is finished several times with a gravure roll to obtain the leather-like sheet material of the present invention. In the application of the solution of the polyurethane resin containing the polyurethane elastomer (E) to release paper, the solution is not always uniform depending on the use of the obtained leather-like sheet, but is usually formed. The thickness of the resin layer for the skin is 10
A solution concentration and a coating amount that are 100 μm are adopted. Further, as a solution of the resin for the adhesive, 30
A solution having a resin concentration of ５０50% by weight is 60-150 g / m ^2.
When applied on the resin layer for skin with an application amount of, an adhesive layer having a thickness of several tens of μm is formed after drying. Further, a resin film having releasability may be used in place of the above release paper, and as a method of forming a resin layer for a skin on the release paper or on the resin film, polyurethane resin may be used instead of hot air drying. A method of coagulating a polyurethane resin by immersing a release paper or a resin film coated with the resin solution in a non-solvent of the polyurethane resin can also be adopted.

As a method for producing a leather-like sheet by a wet method, for example, a fiber substrate is impregnated and / or coated with a solution of a polyurethane resin, and then immersed in a non-solvent of the polyurethane resin. A method including forming a layer made of a polyurethane resin can be adopted. The leather-like sheet material of the present invention may be subjected to various post-treatments as required for ordinary synthetic leather and artificial leather as necessary. Such post-processing includes, for example, embossing; kneading;
Wrinkle processing; softener treatment; top coat for improving feeling, coloring, surface properties, and the like.

[0049]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the examples, the compounds may be represented by the following abbreviations. BD: 1,4-butanediol DMF: N, N-dimethylformamide EG: ethylene glycol MDI: 4,4′-diphenylmethane diisocyanate MPD: 3-methyl-1,5-pentanediol MOD: 2-methyl-1,8 -Octanediol ND: 1,9-nonanediol

Example 1 Polyester diol 5 having a number average molecular weight of 2000 obtained by condensation polymerization of MPD and adipic acid
0% by weight and a mixture of ND and MOD (molar ratio: 50:
50) and 50% by weight of a polycarbonate diol having a number average molecular weight of 2000 obtained by condensation polymerization of ethylene carbonate and a mixed polymer diol, M
DI and EG (mol ratio of polymer diol, MDI and EG is 1: 4: 3) are reacted in a DMF solvent at 85 ° C. for about 8 hours according to a conventional method to give a concentration of 25.
A solution of a% by weight of the polyurethane elastomer for the skin layer in DMF was obtained. The viscosity of the solution at 30 ° C. was 400 poise. The solution was diluted with methyl ethyl ketone to obtain a polyurethane solution for a skin layer having a solid content of 20% by weight.

A polyester-based diol having a number average molecular weight of 1,000 and tolylene diisocyanate obtained by condensation polymerization of MPD and adipic acid are subjected to a urethanization reaction in a toluene solvent under reflux of the solvent,
Next, the mixture was diluted with a mixed solvent of DMF and ethyl acetate to obtain a solution-based polyurethane base material for an adhesive having a solid content of 45% by weight and a viscosity of 800 poise (30 ° C.). Then, the main agent 10
To 0 parts by weight, 5.5 parts by weight of a tolylene diisocyanate adduct of trimethylolpropane as a curing agent and a desired amount of DMF were added to obtain a polyurethane solution for adhesion having a viscosity of 60 poise (30 ° C.).

Using a knife coater, a polyurethane solution for a skin layer (solid content: 20% by weight) was applied on a release paper in an amount to give a dry thickness of 25 μm.
By heating and drying for minutes, a polyurethane film for the skin layer was formed. Next, a polyurethane solution for an adhesive was applied on the above-mentioned film using a knife coater in an amount such that a basis weight of 120 g / m ² was obtained.
The non-raised surface of the raised fabric obtained by cross-weaving using polyester yarn as warp yarn and rayon yarn as weft yarn was bonded together, and then pressed with a laminating roll. The obtained laminate was dried at 100 ° C. for 2 minutes, and dried at 50 ° C.
After curing at 3 ° C. for 3 days, the release paper was peeled off to obtain a leather-like sheet.

A part of the obtained leather-like sheet was treated with a jungle tester at a relative humidity of 95% and a temperature of 70 ° C. for 6 weeks (1000 hours). For each of the leather-like sheet not subjected to the jungle test and the leather-like sheet subjected to the jungle test, ten adult panelists felt slimy based on tactile sense (touch) and visual sense (visually). And the surface smoothness of the epidermis was evaluated. Regarding the sliminess, each panelist "has a moist and very good sliminess", "has a good sliminess", and "feels slightly slimy" And "No sliminess" at all. The sliminess was scored by numerical values (3, 2, 1 and 0, respectively) corresponding to each evaluation. The surface smoothness was evaluated by each panel on a four-point scale: "very smooth,""almostsmooth,""slightlysmooth," and "no smoothness was felt." Then, the surface smoothness was scored by numerical values (3, 2, 1, and 0, respectively) corresponding to each evaluation. Table 1 shows the average score of each paneler for the slimy feeling and the surface smoothness.

[0054]

[Table 1]

As is evident from Table 1, the obtained leather-like sheet-like material is a sheet having a high quality feeling because it has extremely good surface smoothness and a strong slimy feeling. The leather-like sheet is a highly durable sheet having excellent hydrolysis resistance because it retains extremely good surface smoothness and a moist slimy feeling even after being subjected to a jungle test. .

Comparative Example 1 A polycarbonate diol having a number average molecular weight of 2,000 obtained by subjecting a mixture of ND and MOD (molar ratio: 50:50) to condensation polymerization with ethylene carbonate,
MDI and EG (Polycarbonate diol and MD
The molar ratio of I to EG is 1: 4: 3) in DMF solvent at 85
The reaction was carried out at 7.5 ° C. for about 7.5 hours to obtain a solution of 25% by weight of polyurethane in DMF. 3 of the solution
The viscosity at 0 ° C. was 390 poise.

The solution was diluted with methyl ethyl ketone to obtain a polyurethane solution for a skin layer having a solid content of 20% by weight. A leather-like sheet was obtained in the same manner as in Example 1 except that the thus obtained polyurethane solution for a skin layer was used. Each of the sample of the leather-like sheet obtained in this way and the sample obtained by subjecting it to a jungle test was evaluated for the slickness and surface smoothness as in Example 1. Table 2 shows the average score of each panelist.

[0058]

[Table 2]

As is evident from Table 2, the obtained leather-like sheet material has a good surface smoothness, but lacks a luxurious feeling because it does not give a moist and slimy feeling. is there.

Comparative Example 2 Polyester diol having a number average molecular weight of 2,000, which was obtained by condensation polymerization of MPD and adipic acid,
By reacting MDI and EG (polyester diol: MDI: EG in a molar ratio of 1: 4: 3) in a DMF solvent at 85 ° C. for about 8.4 hours, a solution of a 25% by weight polyurethane in DMF was obtained. Obtained. 30 ° C of the solution
Was 380 poise.

The solution was diluted with methyl ethyl ketone to obtain a polyurethane solution for a skin layer having a solid content of 20% by weight. A leather-like sheet was obtained in the same manner as in Example 1 except that the thus obtained polyurethane solution for a skin layer was used.

Each of the leather-like sheet sample thus obtained and the sample obtained by subjecting it to a jungle test were evaluated for the slickness and surface smoothness in the same manner as in Example 1. went. Table 3 shows the average score of each panelist.

[0063]

[Table 3]

As is evident from Table 3, the obtained leather-like sheet material has a good surface smoothness, but does not have a moist and slimy feeling and is inferior in hydrolysis resistance. After the jungle test, the surface smoothness and the slimy feeling deteriorated remarkably.

Examples 2 to 4 and Comparative Example 3 The molar ratio between ND and MOD used for producing the polycarbonate-based polyol (A-2), and the polyester-based polyol (A- 1) and the polycarbonate-based polyol (A-2) in the same manner as in Example 1 except that the conditions shown in Table 4 were employed as the number average molecular weight and the mixing ratio and the molar ratio between these polymer polyols, MDI and EG. A solution of 25% by weight of polyurethane in DMF was obtained. The viscosity of the solution at 30 ° C. was about 400 poise.

For each of the sample of the leather-like sheet obtained in this way and the sample obtained by subjecting it to a jungle test, evaluation of the slickness and surface smoothness as in Example 1 was performed. went. Table 4 also shows the average evaluation based on the score of each panelist.

[0067]

[Table 4]

(Note 1) The symbols in the evaluation columns for sliminess and surface smoothness are: ：: extremely good, 、: good, ×: bad. The symbols in the durability evaluation column indicate the slimy feeling and surface smoothness after the jungle test (6 weeks): ：: no change, ×: remarkable decrease

As is evident from Table 4, the leather-like sheets obtained in Examples 2 to 4 are all excellent in surface smoothness, slimy feeling and durability thereof. On the other hand, the leather-like sheet obtained in Comparative Example 3 hardly gives a moist and slimy feeling.

Example 5 As a polyester-based diol, a mixture of MPD and BD (molar ratio: 6: 4; the sum of the product of the mole fraction of each diol and the number of carbon atoms of the diol is 5.2) and adipic acid Has a number average molecular weight of 20 obtained by condensation polymerization of
Example 1 except that the polyester-based diol No. 00 was used.
In the same manner as in the above, a solution of a polyurethane elastomer for a skin layer having a concentration of 25% by weight in DMF was obtained. The viscosity of the solution at 30 ° C. was 410 poise. By diluting the solution with methyl ethyl ketone, a solid concentration of 2
A 0% by weight polyurethane solution for a skin layer was obtained. A leather-like sheet was obtained in the same manner as in Example 1 except that the thus obtained polyurethane solution for a skin layer was used.

The leathery sheet-like sample thus obtained and the sample obtained by subjecting it to the jungle test were evaluated for the slimyness and surface smoothness as in Example 1. went. According to the average evaluation based on the score of each panelist, the obtained leather-like sheet has extremely good surface smoothness and slimy feeling, and even after the jungle test, these good surface smoothness are obtained. Sex and sliminess were maintained.

Example 6 As a polyester diol, a mixture of MPD and EG (molar ratio: 7: 3; the sum of the product of the mole fraction of each diol and the number of carbon atoms of the diol is 4.8) and adipic acid Has a number average molecular weight of 20 obtained by condensation polymerization of
Example 1 except that the polyester-based diol No. 00 was used.
In the same manner as in the above, a solution of a polyurethane elastomer for a skin layer having a concentration of 25% by weight in DMF was obtained. The viscosity of the solution at 30 ° C. was 400 poise. By diluting the solution with methyl ethyl ketone, a solid concentration of 2
A 0% by weight polyurethane solution for a skin layer was obtained. A leather-like sheet was obtained in the same manner as in Example 1 except that the thus obtained polyurethane solution for a skin layer was used.

Each of the leather-like sheet sample thus obtained and the sample obtained by subjecting it to a jungle test were evaluated for the slimyness and surface smoothness as in Example 1. went. According to the average evaluation based on the score of each panelist, the obtained leather-like sheet material has good surface smoothness and slimy feeling, and after the jungle test, these surface smoothness and slimy feeling are obtained. Although slightly reduced, it was still good.

Example 7 Polyester diol 5 having a number average molecular weight of 2,000 and obtained by condensation polymerization of MPD and adipic acid
0% by weight and a mixture of ND and MOD (molar ratio: 50:
50) and a mixed polymer diol comprising 50% by weight of a polycarbonate diol having a number average molecular weight of 2000 and obtained by condensation polymerization of ethylene carbonate, MDI, and EG (molar ratio of polymer diol, MDI and EG is 1: 9: 8) According to a conventional method, DM
The solution was reacted at 85 ° C. for about 8.2 hours in the F solution to obtain a 25% by weight polyurethane solution in DMF. The viscosity of the solution at 30 ° C. was 400 poise.

The solution was diluted with DMF so that the solid content became 13% by weight, and the weight ratio of the alcohol-modified silicone oil as an additive to the polyoxyethylene / polyoxypropylene block copolymer was 0.5: 20% by weight of the mixture of 1 with respect to the polyurethane elastomer
And a carbon black as a coloring material was added in an amount of 1% by weight based on the polyurethane elastomer to prepare a polyurethane elastomer composition liquid.

This polyurethane elastomer composition was applied on a polyethylene sheet by a casting method so as to have a composition amount of 500 g / m ² (polyurethane amount: 62 g / m ² ). It was immersed in a coagulation liquid at 40 ° C. The coagulated polyurethane elastomer sheet was peeled off from the polyethylene sheet, the solvent was removed in 80 ° C. hot water, washed, and dried to obtain a porous polyurethane sheet. Such a porous polyurethane sheet has a basis weight of 72 g / m ² , a thickness of 0.36 mm, an apparent density of 0.2 g / cm ³ , and a sponge structure having long pores extending in a direction substantially perpendicular to the surface. It was soft with a very smooth surface.

After the surface of the porous sheet which was in contact with the polyethylene sheet was adhered to a nylon tricot with a cross-linked polyurethane adhesive, the surface of the porous sheet was sanded with a thickness of about 0.04 to 0.05 mm. When the internal porosity was exposed by polishing until
A suede-like leather-like sheet having a beautiful appearance and formed by uniform pores was obtained. This leather-like sheet was a high-quality black sheet having a moist, slimy feel, rich in flexibility and drape, and suitable as a material for clothing. In addition, the leather-like sheet material had a good feeling such as a moist slimy feeling even after the jungle test.

Comparative Example 4 A polyester-based diol having a number average molecular weight of 2000, MDI and BD (molar ratio 1: 9: 8) obtained by subjecting MPD and adipic acid to condensation polymerization were dissolved in a DMF solvent according to a conventional method. By reacting at 85 ° C. for about 8 hours, a solution of a polyurethane elastomer having a concentration of 25% by weight in DMF was obtained. The viscosity of the solution at 30 ° C. is 41
It was 0 poise. Preparation of a polyurethane elastomer composition solution, production of a porous polyurethane sheet, and production of a leather-like sheet were carried out in the same manner as in Example 7 except that the polyurethane elastomer solution thus obtained was used.

The obtained porous polyurethane sheet had a basis weight of 73 g / m ² , a thickness of 0.30 mm, and an apparent density of 0.24.
g / cm ³ , and had a sponge structure with irregular pores and a surface with many irregularities. Further, the suede-like leather-like sheet material obtained by using the same did not give a moist slimy feeling and did not have a high-grade feeling.

Example 8 Polyester diol 3 having a number average molecular weight of 2000 and obtained by condensation polymerization of MPD and adipic acid
0% by weight and a mixture of ND and MOD (molar ratio: 30:
70) and a mixed polymer diol comprising 70% by weight of a polycarbonate diol having a number average molecular weight of 2000 and obtained by condensation polymerization of ethylene carbonate, MDI, and EG (the molar ratio of the polymer diol, MDI and EG is 1: 8: 7) according to a conventional method,
The solution was reacted at 85 ° C. for about 8.5 hours in an F solvent to obtain a 25% by weight polyurethane solution in DMF. The viscosity of the solution at 30 ° C. was 390 poise.

The solution was diluted with DMF so that the solid content became 13% by weight, and the weight ratio of the alcohol-modified silicone oil as an additive to the polyoxyethylene / polyoxypropylene block copolymer was 0.5%. : 1
Was added in an amount of 20% by weight based on the polyurethane elastomer to prepare a polyurethane elastomer composition liquid.

This polyurethane elastomer composition solution was applied onto a polyethylene sheet so as to have a liquid volume of 600 g / m ^2, and then immersed in a coagulation solution consisting of a 25% by weight aqueous solution of dimethylformamide at a temperature of 40 ° C. The coagulated polyurethane elastomer sheet was peeled off from the polyethylene sheet, the solvent was removed in hot water, washed, and dried to obtain a porous polyurethane sheet having extremely good surface smoothness.

This porous sheet is adhered to a 1.2 mm-thick fiber substrate obtained by adding a polyester-based polyurethane in a nylon-6 ultrafine fiber bundle fiber-entangled nonwoven fabric with a polyurethane-based adhesive. Then, a silver-finished leather-like sheet was obtained by embossing.

The obtained leather-like sheet-like material had a good embossed pattern imparted thereto. The sheet-like material generated many thin and long folds, and gave a moist feeling of sliminess and an apparent weight. And a luxurious leather-like sheet having Further, this leather-like sheet material retained the above various favorable characteristics even after the jungle test.

Example 9 Polyester diol having a number average molecular weight of 2000 obtained by condensation polymerization of MPD and adipic acid,
By condensation-polymerizing a polycarbonate diol having a number average molecular weight of 2,000 and a 1,6-hexanediol obtained by condensation-polymerizing a mixture of ND and MOD (molar ratio: 30:70) with ethylene carbonate, and 1,6-hexanediol, and ethylene carbonate The weight ratio of the obtained polycarbonate diol having a number average molecular weight of 2000 is 30: 4.
A solution of polyurethane in DMF having a concentration of 25% by weight was obtained in the same manner as in Example 8, except that a polymer diol consisting of a mixture of 2:38 was used. 30 ° C of the solution
Was 410 poise. A silver-finished leather-like sheet was obtained in the same manner as in Example 8 except that such a polyurethane solution was used.

The obtained leather-like sheet was slightly inferior to that obtained in Example 8, but had a moist and slimy feeling. Even after the jungle test, the slimy feeling was sufficient. Was held.

Example 10 Polyester diol 3 having a number average molecular weight of 2000 and obtained by subjecting MPD to adipic acid by condensation polymerization
0% by weight and a mixture of ND and MOD (molar ratio: 60:
40) and ethylene carbonate, a mixed polymer diol comprising 70% by weight of a polycarbonate diol having a number average molecular weight of 2,000, obtained by condensation polymerization of ethylene carbonate, MDI, and EG (molar ratio of polymer diol, MDI and EG is 1: 8: 7) according to a conventional method,
The solution was reacted at 85 ° C. for about 7.8 hours in an F solvent to obtain a solution of 25% by weight of polyurethane [hereinafter referred to as polyurethane (X)] in DMF. 3 of the solution
The viscosity at 0 ° C. was 380 poise.

Polybutylene adipate having a number average molecular weight of 2000, MDI and BD (molar ratio 1: 7.9: 6.
9) was reacted in a DMF solvent at 85 ° C. for about 8 hours according to a conventional method to obtain a solution of a 25% by weight polyurethane elastomer [hereinafter referred to as polyurethane elastomer (Y)] in DMF. The viscosity of the solution at 30 ° C. was 370 poise.

The two kinds of polyurethane elastomer solutions thus obtained were mixed so that the weight ratio of the polyurethane elastomer (X) to the polyurethane elastomer (Y) was 70:30, and the solid content was 13% by weight. %, And diluted with an alcohol-modified silicone oil as an additive and a polyoxyethylene / polyoxypropylene block copolymer in a weight ratio of 0.1%.
A 5: 1 mixture is applied to the polyurethane elastomer at 2
A polyurethane elastomer composition liquid was prepared by adding it in an amount of 0% by weight.

This polyurethane elastomer composition solution was applied onto a polyethylene sheet so as to have a liquid volume of 600 g / m ^2, and then immersed in a coagulation solution of a 25% by weight aqueous solution of dimethylformamide at a temperature of 40 ° C. The coagulated polyurethane elastomer sheet was peeled off from the polyethylene sheet, the solvent was removed in hot water, washed, and dried to obtain a porous polyurethane sheet having extremely good surface smoothness.

This porous sheet is adhered to a 1.2 mm-thick fiber base material obtained by incorporating a polyester-based polyurethane in a nylon-6 ultrafine fiber bundle fiber-entangled nonwoven fabric with a polyurethane-based adhesive. Then, a silver-finished leather-like sheet was obtained by embossing.

The obtained leather-like sheet is a high-quality leather-like sheet having a moist and slimy feeling and an apparent weight, and retains these favorable characteristics even after the jungle test. I was

Comparative Example 5 A polyester diol having a number average molecular weight of 2,000 obtained by condensation polymerization of MPD and adipic acid,
MDI and EG (polymer diol, MDI and EG
(8: 7) in a DMF solvent at 85 ° C. for about 8.2 hours to obtain a 25% by weight polyurethane solution in DMF. The viscosity of the solution at 30 ° C. was 390 poise.

The polyurethane elastomer was prepared in the same manner as in Example 10 except that the DMF solution of the polyurethane elastomer having a concentration of 25% by weight thus obtained was used instead of the DMF solution of the polyurethane elastomer (X) having the same concentration. After mixing with the DMF solution of (Y), preparation of a polyurethane elastomer composition solution, production of a porous polyurethane sheet, and production of a leather-like sheet with silver finish were performed.

Although the obtained porous polyurethane sheet had substantially good surface smoothness, the obtained leather-like sheet with silver did not give a moist, slimy feeling and a jungle test. Later, the surface was insufficient in durability such as cracks on the silver surface.

Example 11 The same procedure as in Example 1 was carried out except that a polyester diol having a number average molecular weight of 2,000 obtained by condensation polymerization of 1,5-pentanediol and adipic acid was used as the polyester diol. A solution of a 25% by weight polyurethane elastomer for a skin layer in DMF was obtained. The viscosity of the solution at 30 ° C. was 420 poise. The solution was diluted with methyl ethyl ketone to obtain a polyurethane solution for a skin layer having a solid content of 20% by weight. A leather-like sheet was obtained in the same manner as in Example 1 except that the thus obtained polyurethane solution for a skin layer was used.

The leather-like sheet-like sample thus obtained and the sample obtained by subjecting it to the jungle test were evaluated for the slickness and surface smoothness as in Example 1. went. According to the average evaluation based on the score of each panelist, the obtained leather-like sheet was inferior to the leather-like sheet obtained in Example 1, but had a good slimy feeling. Even afterwards, a good slimy feeling was maintained. Further, the obtained leather-like sheet had extremely good surface smoothness, and even after the jungle test, the good surface smoothness was maintained.

[0098]

As is clear from the above examples, according to the present invention, there is provided a durable film which has a good slimy feeling and can maintain the good slimy feeling for a long period of time even under high temperature and high humidity. A novel leather-like sheet having excellent properties is provided. Among the leather-like sheet materials provided by the present invention, the leather-like sheet material with a tone of silver has a very good surface smoothness on the silver surface, and the surface-treated leather-like sheet material has a wrinkled form. And a good appearance in terms of embossing-type fixing properties. Further, among the leather-like sheet materials provided by the present invention, a suede-like leather-like sheet material has a good suede feeling. Further, the leather-like sheet material provided by the present invention is excellent in secondary workability, for example, cutting workability, sewing workability, plowing, embossability, and the like.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) D06N 3/14 C08G 18/42-18/44

Claims (1)

(57) [Claims] 1. A leather-like sheet comprising a fiber base and a polyurethane resin, wherein the polyurethane resin has (A) a carbon number derived from 1,5-pentanediol which may be substituted by a methyl group. At least one alkane selected from the group consisting of a polyester polyol containing 5 to 6 alkanediol units and a dicarboxylic acid unit and 1,8-octanediol and 1,9-nonanediol which may be substituted with a methyl group; An alkanediol unit having 8 to 10 carbon atoms derived from a diol and a compound represented by the formula: And (B) an organic diisocyanate comprising a polycarbonate polyol substantially consisting of a carbonyl unit represented by the following formula, wherein the polyester polyol and the polycarbonate polyol have a weight ratio of 5:95 to 80:20. A leather-like sheet comprising a polyurethane elastomer obtained by reacting