JPH06158557A - Leather-like sheet material - Google Patents

Abstract

PURPOSE:To provide a leather-like sheet material having dry and slimy surface touch and excellent feeling, drapability and durability. CONSTITUTION:An organic solvent solution composed of (A) a polyurethane produced by reacting a polymer diol selected from polyester, polycarbonate and polylactone and having a number-average molecular weight of 500-3,000 with a low-molecular chain extender, (B) 5-20 pts.wt. (based on 100 pts.wt. of the component A) of polyethylene glycol having an average molecular weight of >=5,000 and (C) a water-miscible organic solvent is impregnated in and/or applied to a fiber base material and coagulated with a non-solvent of the polyurethane of the component A to obtain the objective leather-like sheet material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leather-like sheet material having a surface slimy touch and having a good texture. More specifically, it has a surface slimy touch obtained by using a composition in which a polyurethane resin having a specific structure and a specific polyethylene glycol are mixed in a specific ratio,
The present invention relates to a leather-like sheet material having a good texture. INDUSTRIAL APPLICABILITY The leather-like sheet material of the present invention has a unique slimy touch without stickiness and is excellent in texture, and thus is useful as a material for clothes, interiors, bags, bags, shoes and the like.

[0002]

2. Description of the Related Art Leather-like sheet materials made of polyurethane as a skin material are widely used as materials for shoes, clothing, furniture, and seats for vehicles such as automobiles. The requirements for quality such as heat resistance and heat resistance are becoming more and more advanced. Many attempts have been made to meet these requirements by improving the properties of polyurethane resins. As one of the means, for example,
The type of polyurethane and its component composition have been changed.

JP-A-2-264086 discloses a polyester diol having a specific composition and a number average molecular weight of 300 to 5,
Sheet-like material obtained by impregnating and / or applying a solution prepared by blending a polyurethane elastomer containing 000 polyoxyalkylene glycol as a diol component with a coagulation regulator having a specific structure onto a fiber substrate and coagulating with a non-solvent of the polyurethane. The manufacturing method of is shown. The publication discloses that polyethylene glycol is included as polyoxyalkylene glycol. It is disclosed that the obtained sheet material has a good smoothness, a softness and a feeling excellent in drapeability.

However, according to the method disclosed in the publication, not only a sheet having good slimy property cannot be obtained, but also a polyurethane having a specific structure, which is a requirement of the present invention, and polyethylene glycol having an average molecular weight of 5,000 or more. It is almost impossible to infer that a leather-like sheet material having a unique slime touch can be obtained by blending in a specific ratio. Further, Japanese Patent Laid-Open Publication No. 1-29439 proposes to use polyoxyethylene alkyl ether or the like as a part of a coagulation regulator for wet coagulation of polyurethane, which is used for such purpose. Has a relatively low molecular weight, and even if the wet sponge-forming property of polyurethane is improved, not only a sheet-like material having a good slimy property cannot be obtained, but also a polyurethane having a specific structure which is a requirement of the present invention. It is almost impossible to infer that a leather-like sheet material having a unique slime touch can be obtained by blending and a polyethylene glycol having an average molecular weight of 5000 or more in a specific ratio.

[0005]

There is a remarkable tendency in recent years in the trend of upsizing in consumer life and the emphasis on sensitivity and fashion. With respect to leather-like sheet materials used as synthetic leather and artificial leather, texture, drape property, and excellent touch feeling have been strongly demanded. Naturally, it must also have physical properties and durability.

By using a polyurethane obtained by polymerizing a specific polymer diol and polyethylene glycol having an average molecular weight of 5000 or more as a polymer diol component, the present inventors have excellent flexibility and drapability and are dry and smooth. A leather-like sheet having a slimy touch was proposed in Japanese Patent Application No. 4-254646. However, although this method can obtain preferable performance, the number of types of raw material polyurethane is increased in industrial production, which is not always preferable in process control. An object of the present invention is to industrially provide a leather-like sheet material having excellent flexibility and drapeability and having a dry slimy touch industrially.

[0007]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors in order to achieve the above object, the average molecular weight was 500.
When 0 or more of polyethylene glycol is used, it is possible to achieve the object of the present invention without causing problems such as bleed-out by simply mixing with polyethylene without copolymerization as a polymer diol component of polyurethane. Found and completed the present invention.

That is, according to the present invention, the above-mentioned objects are: The number average molecular weight selected from the group consisting of polyester, polycarbonate and polylactone is 500 to 3000.
A polyurethane obtained by reacting the polymer diol of above with an organic diisocyanate and a low molecular chain extender, B. 5 to 20 parts by weight of polyethylene glycol having an average molecular weight of 5000 or more (vs. 100 parts by weight of A), C.I. It is achieved by impregnating and / or coating a fiber base material with an organic solvent solution consisting of a water-miscible organic solvent and coagulating with a non-solvent of component A polyurethane.

First, the polymer diol which is a raw material for the polyurethane of the component A used in the present invention will be described.
Polymer diols are polyester, polycarbonate,
It is selected from the group consisting of polylactones. The polyether diol is an essential component of the present invention and has a number average molecular weight of 5,000.
It is a compound similar to the above polyethylene glycol (B), and is not suitable for the purpose of the present invention, probably because it has an affinity and a proper phase separation state considered to be the action mechanism of the present invention cannot be obtained. The number average molecular weight of the polymer diol is 500 to 30.
The range of 00 is desirable, and more preferably 700
A range of up to 2500 is selected. When it is less than 500, the flexibility of the leather-like sheet material tends to be lost, or the texture tends to decrease, which is not preferable. If it exceeds 3,000, the urethane group concentration will inevitably decrease, and not only is it difficult to obtain a leather-like sheet material with a good balance of texture, flexibility, cold resistance, heat resistance, and durability, The polymer
This is not preferable because of the difficulty in industrial production of diol.

As the polymer diol, polyester, polycarbonate and polylactone can be used alone or in a mixture at an arbitrary ratio.

The polyester diol used in the present invention can be obtained, for example, by reacting a dibasic acid with a diol. Dibasic acids include aliphatic dibasic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, and brassic acid, and aromatic dibasic acids such as isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid. It is possible to use one type of basic acid or a combination thereof. Among them, aliphatic dibasic acids, particularly adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, and other dibasic acids having a methylene chain length of 4 to 8 are more preferably used. As the diol, ethylene glycol optionally substituted with lower alcohol, propylene glycol, butanediol, neopentyl glycol, methylpentanediol, hexanediol, heptanediol, octanediol, nonanediol,
One or a mixture of two or more of aliphatic diols such as decanediol and dodecanediol, alicyclic diols such as cyclohexanediol and hydrogenated xylylene glycol, and aromatic diols such as xylylene glycol is used. Among them, aliphatic diols, especially butane diol, methyl pentane diol, hexane diol, heptane diol, methyl octane diol, nonane diol and the like, one or a mixture of two or more aliphatic diols having a carbon chain length of 4 to 9 are used. It is preferably used.

The polycarbonate diol can be obtained, for example, by reacting a carbonate compound with a diol. As the carbonate compound, dimethyl carbonate, diphenyl carbonate, ethylene carbonate and the like can be used. As the diol, ethylene glycol optionally substituted with a lower alcohol, propylene glycol, butanediol, neopentyl glycol, methylpentanediol, hexanediol,
Aliphatic diols such as heptanediol, octanediol, nonanediol, decanediol and dodecanediol, alicyclic diols such as cyclohexanediol and hydrogenated xylylene glycol, and aromatic diols such as xylylene glycol. Mixtures of one or more species are used, among which aliphatic diols are
In particular, one or a mixture of two or more aliphatic diols having a carbon chain length of 4 to 9 such as butanediol, methylpentanediol, hexanediol, heptanediol, methyloctanediol and nonanediol is preferably used.

Examples of polylactone diols include poly-ε-caprolactone diol and poly-trimethyl-ε.
-Caprolactone diol, poly-β-methyl-δ-valerolactone diol and the like can be mentioned.

Examples of the organic diisocyanate used in the present invention include 4,4'-diphenylmethane diisocyanate, 2,4- or 2,6-tolylene diisocyanate, meta or paraphenylene diisocyanate, and 1,5-naphthylene diisocyanate. Aromatic diisocyanate, isophorone diisocyanate,
Cyclohexane diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, 4,4 '
And non-aromatic diisocyanates such as dicyclohexylmethane diisocyanate. Among them, 4,4'-diphenylmethane diisocyanate is an organic diisocyanate that can be reacted with the polymer diol and the chain extender, and the sheet-like product obtained by coagulating with a non-solvent has good surface slimy touch and feel. preferable.

Examples of the low molecular weight chain extender used in the present invention are ethylene glycol, propylene glycol, butanediol, neopentyl glycol, methylpentanediol, hexanediol, heptanediol and octanediol which may be substituted with a lower alcohol. Examples thereof include aliphatic diols such as nonanediol, decanediol and dodecanediol, cyclohexanediol, alicyclic diols such as hydrogenated xylylene glycol, aromatic diols such as xylylene glycol, and diethylene glycol. These can be used alone or as a mixture of two or more. Aliphatic diols are more preferable examples of the low molecular chain extender, and ethylene glycol and butanediol are particularly preferable, and they are suitable in terms of the balance of texture, flexibility, cold resistance and heat resistance of the leather-like sheet material. Used for.

The amount of the low molecular chain extender used is not particularly limited, but it varies depending on its molecular structure, the molecular weight of the polymer diol, the type of organic diisocyanate, and the NCO / OH equivalent ratio. Low molecular chain extender] / [polymer diol] equivalent ratio of 0.5 to
Among them, in most cases, the leather-like sheet obtained from 1 to 5.5 is suitable in terms of feeling, flexibility, cold resistance and heat resistance.

Regarding the solution viscosity of the polyurethane used in the present invention, the texture of the leather-like sheet, drapeability,
In order to improve the slimy feel and the like, it is preferable that the solution viscosity of the solid content concentration of 25% by weight in the dimethylformamide solvent measured at 30 ° C. is 5 to 2000 poise, and especially 50 to 1500 poise.

With regard to a specific operation method for producing polyurethane, a known urethanization reaction technique is used. For example, a polymer diol and a chain extender are mixed and preheated to about 40 ° C to 100 ° C, then an organic diisocyanate is added, and the mixture is reacted at 50 to 140 ° C for several hours, and if necessary, the same kind or different kind as that already used. The desired polyurethane is obtained by mixing the above chain extender and reacting at 20 to 140 ° C. for several hours. In the urethanization reaction, a usual urethanization reaction catalyst such as an organic tin compound, an organic titanium compound, and a tertiary amine may be used if desired. Further, the above reaction may be carried out in the presence of an organic solvent which is inert to the organic diisocyanate.

When the reaction is carried out in the presence of an organic solvent,
It is general to adjust the amount of the organic solvent used so that the solid content at the end of the reaction is 5 to 90% by weight, especially 10 to 60% by weight.

The polyurethane used in the present invention may be blended with various additives as used in ordinary synthetic leather or artificial leather, depending on the purpose of use of the leather-like composite sheet. Examples of such additives include inorganic fillers, hiding agents, softeners, flame retardants, antioxidants, ultraviolet absorbers, dyes, surfactants, coagulation regulators, lubricants and the like.

The number average molecular weight of polyethylene glycol used as the component B of the present invention is 5,000 or more.
It is preferably in the range of 6000 to 30,000. 500
If it is less than 0, a leather-like sheet material having a surface slime touch, which is the maximum effect of the present invention, and has a good texture cannot be obtained. The number average molecular weight may be 5,000 or more,
Usually, polyethylene glycol exceeding 30,000 is difficult to obtain industrially.

The blending amount of polyethylene glycol is in the range of 5 to 20 parts by weight with respect to 100 parts by weight of the component A polyurethane. It is more preferably in the range of 5 to 15 parts by weight. If the blending amount is less than 5 parts by weight (A100 parts by weight), the obtained leather-like sheet will not have a smooth slimy touch. Further, the compounding amount is 20 parts by weight (versus A1
If it is more than 100 parts by weight), the durability of the obtained sheet-like material may be deteriorated, or inconvenience may occur in the post-finishing process.

Examples of the water-miscible solvent used as the component C of the present invention include N, N-dimethylformamide,
Examples include N, N-dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, dioxane and the like. Among them, N, N-dimethylformamide is preferably used. In addition, a non-water-miscible organic solvent may be mixed and used in an amount that does not impair the water-miscibility.

The fiber substrate is a synthetic fiber such as polyamide,
Polyester, vinylon, polyacrylonitrile, etc.,
Artificial fibers such as rayon, cupra, acetate, etc., or natural fibers such as silk, cotton, wool, hemp, etc., knitted fabrics, woven fabrics, non-woven fabrics, three-dimensionally entangled ultrafine fibers with an average single fineness of 0.1 denier or less Any fiber bundle or the like can be used.

Above all, the average single fineness of three-dimensional entanglement is 0.1
A non-woven fabric composed of an ultrafine fiber bundle having a denier or less can be preferably used. The fiber base material was previously treated with a polyurethane resin so that the weight ratio of the ultrafine fiber bundle to polyurethane was 70/30 to 97/3 and the apparent density was 0.4 to 0.8 g / cm ³ . Impregnated cloths are more suitable.

[0026]

The action mechanism by which the leather-like sheet material of the present invention is excellent in feeling, flexibility, cold resistance, heat resistance, durability, and surface touch is not clear, but it has a specific structure. A blend of polyurethane and polyethylene glycol having a number average molecular weight of 5,000 or more is in a proper phase separation state, and the above-mentioned preferable properties may be imparted to a leather sheet material having the polyurethane blend as a skin layer. Conceivable. The leather sheet material of the present invention thus obtained is useful for various applications such as clothing, shoes, bags, furniture and sundries.

[0027]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In the examples, compounds may be abbreviated as follows. DMF: N, N-dimethylformamide MDI: 4,4'-diphenylmethanediisocyanate EG: ethylene glycol PMPA: 3-methyl-1,5-pentanediol number average molecular weight 2000 obtained by condensation polymerization of adipic acid Polyester diol PHC: Polyhexylene carbonate diol with a number average molecular weight of 2000 PCL: Polycaprolactone diol with a number average molecular weight of 2000 PTG: Polytetramethylene glycol with a number average molecular weight of 2000 PEG 2000: Polyethylene glycol with a number average molecular weight of 2000 PEG 20000: Number average molecular weight 20,000 polyethylene glycols

Polyurethane Production Example A polymer diol having the composition shown in Table 1 (the numbers are each g
Number) 1000 g, EG 93 g, and N, N-dimethylformamide (DMF) 2390 g were charged into a three-necked flask equipped with a Dimroth condenser, heated to make a homogeneous solution, and then charged with MDI 500 g as an organic diisocyanate at 80 ° C. under a nitrogen atmosphere. The reaction was allowed to proceed for about 8 hours. Furthermore, add 2390 g of DMF to dilute to give a concentration of 25 wt%
A polyurethane solution of The viscosity (poise) at 30 ° C. of each solution is shown in Table 1.

[0029]

[Table 1]

Examples 1 to 3 and Comparative Examples 1 to 4 Each of the obtained polyurethane solutions was blended in the composition shown in Table 2, and alcohol-modified silicone oil and polyoxyethylene, polyoxypropylene block copolymer were added as additives. A mixture having a weight ratio of 0.5: 1 was used in an amount of 15% by weight with respect to the polyurethane solid content, and a vehicle containing carbon black (manufactured by Dainichiseika Seika Seven BS-780 Black) as a colorant was used with respect to the polyurethane solid content. A polyurethane composition liquid was prepared by adding 50% by weight. The obtained preparation liquid has an average fineness of 0.08.
Three-dimensional entangled non-woven fabric of dr polyethylene terephthalate ultrafine fiber bundle with polyethylene / propylene adipate /
Porous fibrous material having a thickness of 1.2 mm and an apparent density of 0.42 g / cm ³ and containing a polyurethane obtained by polymerizing 4,4′-diphenylmethane diisocyanate / ethylene glycol at an equivalent ratio of 1/5/4 in a porous state 350g on base
/ M ² was applied by knife coating, and subsequently, the mixture was put into water at a temperature of 25 ° C. to be solidified. 4 of the obtained coagulated product
After removing the solvent in hot water at 0 ° C., washing, and drying, a sheet-like material comprising a porous polyurethane layer and a fibrous substrate was obtained.

The sheet-like material thus obtained was subjected to surface treatment and embossing to obtain a leather-like sheet material with silver. The texture, drape, stickiness and slimy feel of these leather-like sheet materials were evaluated. Furthermore, relative humidity 95%, temperature 7
A jungle test was carried out in which the atmosphere was kept at 0 ° C. for 5 weeks. The results are shown in Table 2.

[0032]

[Table 2]

The symbols in the table are ◯: good or no change x: defective or sticky

The leather-like sheet materials of Examples 1 to 3 of the present invention had a uniform polyurethane porous layer and a smooth surface. Furthermore, the touch on the surface was not sticky and had an excellent slimy feel. Moreover, the result of the wet heat test was also good. The leather-like sheet material of Comparative Example 1 was excellent in texture and wet heat test, but had a sticky surface touch and poor sliminess. Comparative Example 2 is a leather-like sheet material which does not use the high molecular weight polyethylene glycol which is an essential component of the present invention. Although this product was excellent in texture and wet heat test, the surface touch had no slimy feeling at all. Comparative Example 3 is a leather-like sheet obtained by blending a high molecular weight polyethylene glycol, which is an essential component of the present invention, in an amount larger than the range specified by the present invention. In this product, waxy matter migrated to cause spots, and the result of the wet heat test was also inferior. Comparative Example 4 is a leather-like sheet material obtained by blending polyethylene glycol having a molecular weight of 2000. This product had a sticky surface and had a poor slimy feel.

[0035]

EFFECT OF THE INVENTION The leather-like sheet material of the present invention has a particularly smooth surface touch, and is excellent in texture, drape, and durability.
It can be applied as a material for interiors, bags, bags, shoes, etc.

Claims (1)

[Claims] 1. A. Polyester, polycarbonate,
The number average molecular weight selected from the group consisting of polylactones is 5
Polyurethane obtained by reacting a polymer diol of 00 to 3000 with an organic diisocyanate and a low molecular chain extender, B. 5 to 20 parts by weight of polyethylene glycol having an average molecular weight of 5000 or more (vs 100 parts by weight of A), C.I. A leather-like sheet obtained by impregnating and / or coating a fiber base material with an organic solvent solution consisting of a water-miscible organic solvent and coagulating with a non-solvent of component A polyurethane.