JP3109762B2 - 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 an excellent texture such as a unique slimy feeling, and is excellent in durability, so that it can be applied to applications where ordinary synthetic leather and artificial leather are used. Yes, for example, it is useful as a material for shoes, bags, bags, clothing, and the like.

[0002]

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. JP-A-2-33384 discloses that a polycarbonate-based polyurethane obtained by reacting a polycarbonate-based polyol containing 2-methyl-1,8-octanediol unit with an organic diisocyanate is used as a skin material to improve flexibility and flexibility. It is described that synthetic leather having good hydrolysis resistance can be produced. On the other hand, JP-A-62-2817 discloses 2-methyl-
A polyester-based polyurethane obtained by reacting a polyester-based polyol containing a 1,8-octanediol unit with an organic diisocyanate has excellent hydrolysis resistance, and the polyester-based polyurethane can be used for synthetic leather and artificial leather. It is described.

[0003]

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 polyester-based polyurethane obtained by reacting a polyester-based polyol containing a 2-methyl-1,8-octanediol unit with an organic diisocyanate as described in the above-mentioned Japanese Patent Application Laid-Open No. 62-22817 is disclosed. It was found that a leather-like sheet having a good slimy feeling could not be obtained. Thus, the purpose of the present invention is
A leather-like sheet made of a fiber substrate and a polyurethane resin, which has a good slimy feeling and is excellent in durability without accompanying deterioration of the good slicky feeling over time. Is to provide.

[0004]

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) an alkanediol unit having 8 to 10 carbon atoms derived from at least one alkanediol selected from the group consisting of 1,8-octanediol and 1,9-nonanediol which may be substituted with a methyl group; Polyester polyol substantially consisting of a dicarboxylic acid unit and the above alkanediol unit and a formula

[0005]

Embedded image Wherein the weight ratio of the polyester-based polyol to the polycarbonate-based polyol is 10%.
This is achieved by providing a leather-like sheet comprising a polyurethane elastomer obtained by reacting a polymer polyol having a ratio of 90 to 90:10 with (B) 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 constitutional units of the polyester-based polyol (A-1), comprises 1,8-octanediol and 1,9-nonanediol which may be substituted with a methyl group. From at least one alkanediol having 8 to 10 carbon atoms selected from the group consisting of
A unit excluding two hydrogen atoms contained in one hydroxyl group [hereinafter, such a unit is referred to as an alkanediol unit (I)], and represented by the general formula:

[0007]

Embedded image (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 (I) has the formula

Embedded image And / or a 1,9-nonanediol unit represented by the formula -O- (CH ₂ ) ₉ -O- (hereinafter referred to as an ND unit) ), The leather-like sheet obtained is particularly excellent in the slimy feeling and the durability thereof, and the coagulability of the polyurethane elastomer in a non-solvent is improved. When it is adopted, it is desirable because a flexible leather-like sheet having uniform fine pores in the polyurethane resin layer can be produced.

The MOD unit and the ND unit which may be contained in the alkanediol unit (I) may be only one of them or both.
It contains both ND units and MOD units as alkanediol units (I), 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 that the ratio be in the range of 0 to 20:80, since the resulting leather-like sheet gives a leather-like sheet with particularly good sliminess and durability. The polyester-based polyol (A-1) may contain one or more diol units other than the alkanediol unit (I). Examples of such diol units include ethylene glycol, propylene glycol, 1,4-butanediol, 3-methyl-1,5-pentanediol,
Saturated aliphatic diols such as 6-hexanediol and neopentyl glycol; saturated alicyclic diols such as 1,4-cyclohexanediol; dihydric aromatic alcohols such as xylylene glycol; And a unit excluding two hydrogen atoms contained therein. 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. The sum of the product of the mole fraction of each diol unit in the polyester-based polyol (A-1), which is 40 mol% or less based on the diol unit, and the number of carbon atoms of each diol unit. Is 6.5 or more, that is, the expression

[0009]

(Equation 1) (Where k represents the number of types of diol units contained in the polyester polyol, Xi represents the number of carbon atoms of the i-th type diol unit, and Mi represents all diols contained in the polyester polyol. I-th unit
(Representing the mole fraction of the second kind of diol unit). 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. Such dicarboxylic acid units include, for example, saturated aliphatic dicarboxylic acids such as adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid; isophthalic acid;
Examples include units in which two hydroxyl groups in two carboxyl groups are removed from a dicarboxylic acid such as an aromatic dicarboxylic acid such as terephthalic acid. Among these dicarboxylic acid units, adipic acid units, azelaic acid units,
It is generally desirable because the leathery sheet-like material from which sebacic acid units and the like are obtained often has particularly good performance such as sliminess and durability. 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
It is substantially composed of a diol unit containing at least one type of alkanediol unit (I) and a dicarboxylic acid unit as described above, but if it is a small amount within a range not impairing the action and effect of the present invention, 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 range of the molecular weight of the polyester-based polyol used as a usual raw material for producing polyurethane is preferably adopted. Among them, the number average molecular weight is 500 to 10,000, especially 800 to 500
0 is a polyester-based polyol (A-1)
It is generally preferred because the handleability of the polyurethane elastomer obtained therefrom becomes good, and the resulting leather-like sheet material often has particularly good sliminess and durability.

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 polyol (A-1) may be 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. 1% in the presence of an esterification catalyst and / or a transesterification catalyst
Esterification or transesterification at 50-250 ° C. and then the resulting reaction product under reduced pressure for 200-30
It can be produced by condensation polymerization at 0 ° 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, contains the alkanediol unit (I) and the carbonyl unit as essential constituent units. And an average of about 2 alcoholic hydroxyl groups at the molecular chain terminals. The alkanediol unit (I) contained in the polycarbonate-based polyol (A-2) is preferably a MOD unit and / or an ND unit, and the leather-like sheet obtained is particularly excellent in sliminess and durability. Desirable.

The MOD unit and the ND unit which may be contained in the alkanediol unit (I) may be only one of them, or both.
It contains both ND units and MOD units as alkanediol units (I), 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 that the ratio be in the range of 0 to 20:80, since the resulting leather-like sheet gives a leather-like sheet with particularly good sliminess and durability. The polycarbonate polyol (A-2) may contain one or more diol units other than the alkanediol unit (I). Examples of such diol units include alkanediols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1.6-hexanediol, 3-methyl-1,5-pentanediol, and neopentyl glycol; A saturated alicyclic diol such as cyclohexanediol; a diol such as a divalent aromatic alcohol such as xylylene glycol;
And a unit excluding two hydrogen atoms contained in each hydroxyl group. The content of the units other than the alkanediol unit (I) is not particularly limited as long as the action and effect of the present invention are not impaired. Generally, the content of all the diol units contained in the polycarbonate polyol (A-2) is On the other hand, it is desirably 40 mol% or less.

Polycarbonate polyol (A-2)
Is substantially composed of a diol unit containing at least one alkanediol unit (I) and a carbonyl unit as described above, but in a small amount within a range not impairing the action and effect of the present invention. , And other structural units. Examples of the constituent units that may be optionally contained include trivalent or higher units in which a hydrogen atom in a hydroxyl group is removed from a trivalent or higher alcohol such as glycerin, pentaerythritol, and trimethylolpropane. Can be Polycarbonate polyol (A-
Although the molecular weight of 2) is not particularly limited,
Used as a raw material for producing ordinary polyurethane,
The range of the molecular weight of the polycarbonate diol such as poly (hexylene carbonate) diol is suitably employed. Among them, when the number average molecular weight is in the range of 500 to 10000, particularly in the range of 800 to 5000, the handleability of the polycarbonate-based polyol (A-2) and the polyurethane obtained therefrom becomes good,
Moreover, since the slimy feeling and the durability of the obtained leather-like sheet material are often particularly good,
Generally 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 ratio of 10:90 to 9: 9.
It is essential to use them together in a weight ratio within the range of 0:10. Polyester polyol (A-1) and polycarbonate polyol (A-2) in polymer polyol
If the weight ratio is outside the above range, a leather-like sheet having a good slimy feeling cannot be obtained. When the weight ratio of the polyester-based polyol (A-1) to the polycarbonate-based polyol (A-2) is within the range of 30:70 to 80:20, the slimy feeling of the obtained leather-like sheet and its durability It is preferable because the property is particularly good.

In the present invention, other polymer polyols may be used 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 polyoxyethylene polyol, polyoxypropylene polyol, and polyoxytetramethylene polyol; polycarbonate-based polyols other than polycarbonate-based polyols (A-2) such as poly (hexylene carbonate) polyol; Is mentioned. As the polyester-based polyol that may be optionally used as described above,
For example, ethylene glycol, propylene glycol,
At least one diol such as 1,4-butanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, xylylene glycol, neopentyl glycol and adipic acid; Examples thereof include condensation polymers with at least one aliphatic or aromatic dicarboxylic acid such as pimelic acid, suberic acid, azelaic acid, sebacic acid, isophthalic acid, and terephthalic 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, and the like 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 a chain extender may be used if desired. 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 and the like Divalent 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, and xylyl Aliphatic, alicyclic or aromatic diamines such as diamine, isophoronediamine, phenylenediamine and tolylenediamine; heterocyclic compounds containing two imino groups in a cyclic structure such as piperazine; adipi Acid 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. It is common to use one kind alone or in combination with at least one kind of the above trihydric or higher alcohols.

A polyurethane elastomer obtained by reacting a polymer polyol comprising a polyester-based polyol (A-1) and a polycarbonate-based polyol (A-2) with an organic diisocyanate and, if necessary, a chain extender [hereinafter referred to as a polyurethane elastomer (E ))
The solution viscosity of is not particularly limited, but the production process passability of the leather-like sheet material becomes good,
In addition, since both the slimy feeling and the durability of the obtained leather-like sheet material often become particularly good, 3
It is generally preferred that the viscosity of a solution having a solids concentration of 25% by weight in dimethylformamide solvent measured at 0 ° C. be 5 to 2000 poise, especially 50 to 900 poise. As to a specific operation method for producing the polyurethane elastomer (E), a known technique of a urethane reaction is used. For example, the above-mentioned polyester-based polyol (A-1), polycarbonate-based polyol (A
-2) A polymer polyol such as is mixed with a chain extender if necessary, and after preheating to about 40 to 100 ° C., an organic diisocyanate is added and reacted at 50 to 140 ° C. for several hours. A desired polyurethane elastomer can be obtained by mixing the same or different chain extenders and reacting at 20 to 140 ° C. for several hours. 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; Hydrocarbons and the like are used alone or in any mixture. These exemplified organic solvents are: You may mix and use with alcohols, such as isopropanol, ethanol, and methanol. When the reaction is carried out in the presence of an organic solvent, the amount of the organic solvent used is generally adjusted so that the solid content at the end of the reaction is 5 to 90% by weight, especially 10 to 60% by weight. It is.

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 a fiber substrate. 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,
At least one low molecular weight diol such as 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, xylylene glycol, neopentyl glycol, and adipic acid, pimelic acid, and suberic acid Polyester-based polyols that are condensation polymers with at least one aliphatic or aromatic dicarboxylic acid such as azelaic acid, sebacic acid, isophthalic acid, terephthalic acid; polyoxyethylene polyol, polyoxypropylene polyol, poly Polyether-based polyols such as oxytetramethylene polyol;
Polylactone-based polyols such as poly (ε-caprolactone) polyol and poly (β-methyl-δ-valerolactone) polyol; polymer polyols such as polycarbonate polyol such as poly (hexylene carbonate) polyol; and organic diisocyanate, if necessary. Polyurethane elastomer obtained by urethanization using an agent and a conventional method. 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 material of the present invention may be a two-dimensional fiber aggregate such as a woven fabric, a knitted fabric, or a nonwoven fabric, which is used for producing ordinary synthetic leather and artificial leather. It is a three-dimensional fiber assembly. Examples of the fibers constituting the fiber base include natural fibers such as cotton, silk, hemp, wool, and asbestos; regenerated fibers such as viscose rayon fibers and copper ammonia rayon fibers; semi-synthetic fibers such as acetate fibers; polyamide fibers (nylon 6 Fiber, nylon 66 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, or one or two kinds thereof. Among these, cotton, polyamide fiber (nylon 6 fiber, nylon 66 fiber, aromatic nylon fiber, etc.), polyvinyl alcohol fiber, polyester fiber, polyurethane fiber, etc. are preferably used. These fibers may be ordinary fibers or specially shaped fibers such as fine fibers and porous fibers. In addition, the fiber base is the above-mentioned fiber aggregate,
It may be impregnated with an elastic polymer such as a polyurethane elastomer other than the polyurethane elastomer (E).

The leather-like sheet of the present invention has a so-called silvery or polymer suede-like form in which a layer made of a polyurethane resin is coated on a fiber substrate, and the polyurethane resin is impregnated in the fiber substrate. Or a so-called fibrous suede-like form. 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. Polyurethane elastomer (E)
Various additives such as those used in ordinary synthetic leather or artificial leather can be blended with the polyurethane-based resin containing depending on the intended 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 material 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 employed. Further, as a solution of the resin for the adhesive, 30
When a solution having a resin concentration of ５０50% by weight is applied on the resin layer for skin at an application amount of 60 to 150 g / m ² , an adhesive layer having a thickness of several tens μm is formed after drying. Further, a resin film having releasability may be used in place of the release paper, and as a method of forming a resin layer for skin on the release paper or on the resin film, instead of hot air drying,
A method of solidifying the polyurethane resin by immersing the release paper or the resin film coated with the polyurethane 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.

[0024]

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 MOD: 2-methyl-1,8-octanediol ND: 1,9-nonanediol

Example 1 50% by weight of a polyester diol having a number average molecular weight of 2000 and a mixture of ND and MOD (molar ratio) obtained by condensation polymerization of a mixture of ND and MOD (molar ratio: 50:50) and adipic acid : 50: 50) and a polycarbonate diol 5 having a number average molecular weight of 2,000, obtained by condensation polymerization of ethylene carbonate.
0% by weight of a mixed polymer diol, MDI, and EG (the molar ratio of polymer diol, MDI and EG is 1: 4: 3) was added to a DMF solvent in a DMF solvent according to a conventional method.
By reacting at about 8 hours for about 8 hours, 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. 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. Polyester diol having a number average molecular weight of 1000 and tolylene diisocyanate obtained by condensation polymerization of MOD and adipic acid are subjected to a urethanation reaction in a toluene solvent under reflux of the solvent, and then DMF and ethyl acetate To obtain a solution-based polyurethane base agent for an adhesive having a solid content of 45% by weight and a viscosity of 900 poise (30 ° C.). Next, 5.5 parts by weight of a tolylene diisocyanate adduct of trimethyllolpropane as a curing agent and D
A desired amount of MF was added to obtain an adhesive polyurethane solution having a viscosity of 65 poise (30 ° C.).

A polyurethane solution for a skin layer (solid content concentration: 20% by weight) was applied on a release paper using a knife coater in such an amount as 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 cloth obtained by cross-weaving was bonded together, and then pressed by 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 material was subjected to 9 weeks (1500 hours) under the conditions of a relative humidity of 95% and a temperature of 70 ° C. using a jungle tester.
Processed. 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 slimy feeling" were evaluated, and numerical values (3, 2, 1 respectively) corresponding to each evaluation were given.
And sliminess was scored in 0). The surface smoothness was evaluated by each panel on a four-point scale of "very smooth", "almost smooth", "slightly smooth" and "no smoothness is felt". ,
Numeric value corresponding to each evaluation (3, 2, 1 and 0 respectively)
Was used to score the surface smoothness. Table 1 shows the average score of each paneler for each of the sliminess and surface smoothness.
Shown in

[0027]

[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 a very 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 370 poise. By diluting the solution with methyl ethyl ketone, a solid concentration of 20
By weight, a polyurethane solution for the skin layer was obtained in a weight percentage. 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.

[0029]

[Table 2] As is clear from Table 2, the obtained leather-like sheet material has a good surface smoothness, but does not have a moist and slimy feeling, and thus lacks a high-grade feel.

Comparative Example 2 Polyester diol, MDI, and EG having a number average molecular weight of 2,000 (polyester diol and MDI) obtained by condensation polymerization of a mixture of ND and MOD (molar ratio: 50:50) and adipic acid By reacting EG at a molar ratio of 1: 4: 3) in a DMF solvent at 85 ° C. for about 8.2 hours, a solution of a 25% by weight polyurethane in DMF was obtained. The viscosity of the solution at 30 ° C. is 40
It was 0 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 3 shows the average score of each panelist.

[0031]

[Table 3] As is evident from Table 3, the obtained leather-like sheet-like material has a good flat smoothness, but does not have much moist and slimy feeling, is poor in hydrolysis resistance, and has a jungle test. Deterioration of surface smoothness and slimy feeling later is remarkable.

Examples 2 to 5 and Comparative Example 3 The molar ratio of ND to MOD used for producing the polyester-based polyol (A-1) and the polycarbonate-based polyol (A-2), and for producing the polyurethane Polyester polyol (A-
Same as in Example 1 except that the conditions shown in Table 4 were employed as the number average molecular weight and mixing ratio of the 1) and the polycarbonate polyol (A-2) and the molar ratio of these polymer polyols to MDI and EG. Thus, a solution of 25% by weight of polyurethane in DMF was obtained. The viscosity of the solution at 30 ° C. was about 400 poise. 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 4 also shows the average evaluation based on the score of each panelist.

[0033]

[Table 4] As is clear from Table 4, the leather-like sheet materials obtained in Examples 2 to 5 are all excellent in surface smoothness, sliminess and durability thereof. On the other hand, the leather-like sheet obtained in Comparative Example 3 hardly gives a moist and slimy feeling.

Example 6 As polyester diols, ND, MOD and BD
(Molar ratio is 30:30:40; the sum of the product of the mole fraction of each diol and the number of carbon atoms in the diol is 7.0) and the number average molecular weight obtained by subjecting adipic acid to condensation polymerization. A solution of polyurethane in DMF having a concentration of 25% by weight was obtained in the same manner as in Example 1 except that 2,000 polyester diols were used. 30 ° C of the solution
Was about 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. 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 7 ND, MOD and E as polyester polyols
A mixture of G (molar ratio: 30:30:40; the sum of the product of the molar fraction of each diol and the number of carbon atoms of the diol is 6.2)
25% by weight in the same manner as in Example 1 except that a polyester diol having a number average molecular weight of 2,000 obtained by subjecting condensation polymerization of adipic acid to adipic acid is used.
A solution of the polyurethane in DMF was obtained. 30 of the solution
The viscosity at ° C. was about 410 poise. By diluting the solution with methyl ethyl ketone, a solid concentration of 20
By weight, a polyurethane solution for the skin layer was obtained in a weight percentage. 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. According to the average evaluation based on the score of each panelist, the obtained leather-like sheet has a good surface smoothness and a slimy feeling, and even after the jungle test, the surface smoothness and the slimy Although the feeling was slightly lowered, it was still good.

Example 8 A mixture of ND and MOD (molar ratio: 50:50) and adipic acid was subjected to condensation polymerization to obtain 50% by weight of a polyester diol having a number average molecular weight of 2000 and a mixture of ND and MOD (molar). Ratio: 50:50) and a polycarbonate diol 5 having a number average molecular weight of 2,000, obtained by condensation polymerization of ethylene carbonate.
0% by weight of a mixed polymer diol, MDI, and EG (the molar ratio of polymer diol, MDI and EG is 1: 9: 8) was added to a DMF solvent by a conventional method.
The reaction was carried out at a temperature of about 8.2 hours to obtain a solution of polyurethane having a concentration of 25% by weight in DMF. 3 of the solution
The viscosity at 0 ° C. was 440 poise. The solution is diluted with DMF to a solid concentration of 15% by weight, and a mixture of an alcohol-modified silicone oil as an additive and a polyoxyethylene / polyoxypropylene block copolymer in a weight ratio of 0.5: 1. Was added in an amount of 20% by weight based on the polyurethane elastomer, and carbon black as a coloring material was added in an amount of 1% by weight based on the polyurethane elastomer, thereby preparing a polyurethane elastomer composition liquid.

This polyurethane elastomer composition solution 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 ), and then a dimethylformamide 25% by weight aqueous solution was prepared. It was immersed in a coagulation liquid at 40 ° C. The solidified polyurethane elastomer sheet is peeled off from the polyethylene sheet,
The porous polyurethane sheet was obtained by removing the solvent in 80 ° C. hot water, washing, and drying. Such a porous polyurethane sheet has a basis weight of 65 g / m ² and a thickness of 0.30.
mm, an apparent density of 0.20 g / cm ³ , and was soft with a sponge structure having long holes extending almost perpendicular to the surface and an extremely smooth surface. After the surface of the porous sheet that 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 about 0.04
When the inner porosity was exposed by polishing to a thickness of about 0.05 mm, 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 and slimy feeling, and also rich in flexibility and drape, and was 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 Polycarbonate diol having a number average molecular weight of 2000, obtained by subjecting a mixture of ND and MOD (molar ratio: 50:50) to condensation polymerization with ethylene carbonate,
MDI and EG (polymer diol, MDI and EG
Was reacted 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. 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 8 except that the polyurethane elastomer solution thus obtained was used.
The obtained porous polyurethane sheet has a basis weight of 73 g /
m ² , thickness 0.30 mm, apparent density 0.24 g / cm ³ , and had a somewhat honey sponge structure and a surface with many irregularities. The suede-like leather-like sheet material obtained by using the same did not give much moist slimy feeling and lacked luxury.

Example 9 A mixture of ND and MOD (molar ratio: 60:40) and 30% by weight of a polyester diol having a number-average molecular weight of 2,000 obtained by condensation polymerization of adipic acid and a mixture of ND and MOD (molar ratio) Ratio: 30:70) and a polycarbonate diol 7 having a number average molecular weight of 2000, obtained by condensation polymerization of ethylene carbonate.
0% by weight of a mixed polymer diol, MDI, and EG (the molar ratio of polymer diol, MDI and EG is 1: 8: 7) was added to a DMF solvent in a DMF solvent according to a conventional method.
The reaction was carried out at a temperature of about 9.2 hours to obtain a solution of 25% by weight of polyurethane in DMF. 3 of the solution
The viscosity at 0 ° C. was 410 poise. The solution is diluted with DMF to a solid concentration of 18% by weight, and a mixture of an alcohol-modified silicone oil as an additive and a polyoxyethylene / polyoxypropylene block copolymer in a weight ratio of 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 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, and embossed. By doing so, a leather-like sheet with silver finish was obtained. The applied state of the embossed pattern in the obtained leather-like sheet-like material is good, and the sheet-like material generates a large number of thin and long folded wrinkles,
It was a luxurious leather-like sheet having a moist slimy feeling and an apparent weight feeling. Further, the leather-like sheet retained the above various favorable characteristics even after the jungle test.

Example 10 Polyester diol having a number average molecular weight of 2,000, obtained by condensation polymerization of a mixture of ND and MOD (molar ratio: 30:70) with adipic acid, a mixture of ND and MOD (molar ratio: 70) : 30) and a polycarbonate diol having a number average molecular weight of 2,000 obtained by condensation polymerization of ethylene carbonate and a polycarbonate diol having a number average molecular weight of 2,000 obtained by condensation polymerization of 1,6-hexanediol and ethylene carbonate. A 25% by weight polyurethane solution in DMF was obtained in the same manner as in Example 9 except that a polymer diol consisting of a mixture having a weight ratio of 30:42:28 was used. The viscosity of the solution at 30 ° C. is 42
It was 0 poise. A silver-finished leather-like sheet was obtained in the same manner as in Example 9 except that such a polyurethane solution was used. The obtained leather-like sheet was slightly inferior to that obtained in Example 9,
The sheet was moist and slimy, and this slimy feeling was sufficiently maintained even after the jungle test.

Example 11 A mixture of ND and MOD (molar ratio: 30:70) and 30% by weight of a polyester diol having a number average molecular weight of 2,000 obtained by condensation polymerization of adipic acid and a mixture of ND and MOD (molar ratio) Ratio: 60:40) and a polycarbonate diol 7 having a number average molecular weight of 2000, obtained by condensation polymerization of ethylene carbonate.
0% by weight of a mixed polymer diol, MDI, and EG (the molar ratio of polymer diol, MDI and EG is 1: 8: 7) was added to a DMF solvent in a DMF solvent according to a conventional method.
The reaction was carried out at 8.2 ° C. for about 8.2 hours to obtain a solution of 25% by weight of polyurethane [hereinafter referred to as polyurethane (X)] in DMF. The viscosity of the solution at 30 ° C. was 430 poise. Polyhexylene carbonate having a number average molecular weight of 2,000, MDI and BD (molar ratio 1: 7.9: 6.9) were dissolved in a DMF solvent in a DMF solvent according to a conventional method.
By reacting at 5 ° C for about 8 hours, the concentration is 25% by weight.
(Hereinafter referred to as polyurethane elastomer (Y)) in DMF. The viscosity of the solution at 30 ° C. was 370 poise.

The two types of polyurethane elastomer solutions thus obtained were mixed so that the weight ratio of the polyurethane elastomer (X) to the polyurethane elastomer (Y) was 75:25, 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 liquid was applied onto a polyethylene sheet at a liquid amount of 600 g / m ^2.
Then, it was 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, and embossed. By doing so, a leather-like sheet with silver finish was obtained. The obtained leather-like sheet material was a high-quality leather-like sheet having a moist slimy feeling and an apparent weight feeling, and retained these favorable characteristics even after the jungle test.

Comparative Example 5 Polyester diol having a number average molecular weight of 2000, MDI, and EG (polymer diol and MDI) obtained by condensation polymerization of a mixture of ND and MOD (molar ratio: 30:70) and adipic acid The molar ratio of EG is 1:
8: 7) in a DMF solvent at 85 ° C. for about 9.0 hours to give a 25% by weight polyurethane DM.
A solution in F was obtained. The viscosity of the solution at 30 ° C. was 410 poise. The concentration of 25% by weight thus obtained
The polyurethane elastomer (Y) was mixed with the DMF solution of the polyurethane elastomer (Y) in the same manner as in Example 11 except that the DMF solution of the polyurethane elastomer (X) was used instead of the DMF solution of the polyurethane elastomer (X) having the same concentration. Preparation of a liquid, 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 almost good surface smoothness, the obtained leather-like sheet with silver did not have a moist and slimy feeling, and had a silvery appearance after the jungle test. The surface had insufficient durability such as cracks.

Example 12 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 1,8-octanediol and adipic acid was used as the polyester diol. A solution of a 25% by weight polyurethane elastomer for a surface layer in DMF was obtained. The viscosity of the solution at 30 ° C. was 430 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.
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.

[0046]

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.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-266679 (JP, A) JP-A-62-15390 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D06N 3/14 C08G 18/42

Claims (1)

(57) [Claims] 1. A leather-like sheet comprising a fiber substrate and a polyurethane resin, wherein the polyurethane resin is (A) 1,8-octanediol and 1,9-nonane which may be substituted by a methyl group. A polyester polyol substantially consisting of an alkanediol unit having 8 to 10 carbon atoms derived from at least one alkanediol selected from the group consisting of diols and a dicarboxylic acid unit, and the above-mentioned alkanediol unit and a compound represented by the formula: Wherein the weight ratio of the polyester-based polyol to the polycarbonate-based polyol is 1
A leather-like sheet comprising a polyurethane elastomer obtained by reacting a polymer polyol in the range of 0:90 to 90:10 with (B) an organic diisocyanate.