JP3121457B2 - Leather-like sheet with good stain resistance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a leather-like sheet having excellent stain resistance. More specifically, it is excellent in various physical properties such as mechanical properties, durability, processing suitability, and contamination resistance obtained by mixing and reacting specific components constituting polyurethane resin in a specific order in a specific composition and composition. A good leather-like sheet.

[0002]

2. Description of the Related Art Polyurethane is excellent in mechanical performance and impregnated and / or coated with a solution of polyurethane on a fibrous substrate.
Leather-like sheets obtained by forming naps on the surface of a fibrous structure obtained by wet coagulation or dry coagulation or by applying a surface finishing layer mainly composed of polyurethane are used in various fields. However, as can be seen from the fact that conventional polyurethane resins are used in adhesives, they have good adhesion to various substances, that is, they are very poor in stain resistance because of their good compatibility with dirt components. Was in trouble. As an attempt to improve these disadvantages, attempts have been made to perform a surface treatment with a fluorine compound, but during use, washing, dry cleaning, etc.
Further improvement is desired, for example, drop-off and reduction of the pollution prevention effect are observed.

JP-A-4-178416 and JP-A-4-178417 disclose radical polymerizable unsaturated bonds in the presence of a mercaptan-based chain transfer agent having two or more hydroxyl groups and one mercapto group. A method for producing a polyurethane resin in which a macromonomer (A) obtained by radical polymerization of a monomer, a polyol (B), and a polyisocyanate (C) are reacted, and a polyurethane resin composition comprising the resin is disclosed. These publications disclose 3-mercapto-1,2-propanediol as a mercaptan-based chain transfer agent having two or more hydroxyl groups and one mercapto group, and a perfluoroalkyl group as a monomer having a radical polymerizable unsaturated bond. The resulting polyurethane has been shown to be excellent in water repellency and oil repellency, claiming its superiority. However, the polyurethane resins obtained by the methods of these publications are not particularly limited in the reaction order, or because each component in the resin does not have a controlled sequence structure, in polymerization, Viscosity did not increase sufficiently, or it was difficult to obtain a polyurethane resin having a sufficient balance of various physical properties such as heat resistance, cold resistance, and strength, which was not industrially feasible.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a leather-like sheet having good stain resistance by using a polyurethane having a perfluoroalkyl group and excellent in various physical properties such as mechanical properties and durability and workability. Is provided industrially stably.

[0005]

The present invention is obtained by radical polymerization of a perfluoroalkyl ester of acrylic acid and / or methacrylic acid in the presence of a compound containing two hydroxyl groups and one thiol group. NC with a fluorine-containing diol (A), a polymer diol (B) having a number average molecular weight of 500 to 3,000 selected from the group consisting of polyester, polycarbonate, polylactone and polyether, and an organic diisocyanate (C1)
Intermediate diol having terminal OH (D) obtained by reacting in a quantitative relationship such that the equivalent ratio of O / OH is 0.5 to 0.99
And low molecular diol (E), diphenylmethane-4,4
A leather-like sheet having good stain resistance, comprising a polyurethane obtained by reacting '-diisocyanate (C2) with a fiber structure.

[0006] The fluorine-containing diol (A) can be obtained by a known method. For example, 2,2,2-trifluoroethyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, 2- (perfluorobutyl) ethyl methacrylate in the presence of 3-mercapto-1,2-propanediol 2- (perfluorooctyl) ethyl methacrylate, 2- (perfluorodecyl) ethyl methacrylate, 2- (perfluoro-3-
Methylbutyl) ethyl methacrylate, 2,2,2-trifluoroethyl acrylate, 2,2,3,3,3-
Pentafluoropropyl acrylate, 2- (perfluorobutyl) ethyl acrylate, 2- (perfluorooctyl) ethyl acrylate, 2- (perfluorodecyl) ethyl acrylate, 2- (perfluoro-3-
Methyl butyl) ethyl acrylate, alkyl monomer using an initiator such as azobisisobutyronitrile, azobisisovaleronitrile, banzoyl peroxide,
It can be polymerized. Further, butyl acrylate, methyl methacrylate, butyl methacrylate, methacrylate containing no perfluoroalkyl such as ethyl acrylate, acrylate, and even other copolymerizable vinyl monomers may be used in combination without impairing the object of the present invention. There is no.

[0007] The molecular weight of the fluorine-containing diol (A) is not particularly limited and depends on the monomer used.
It is preferable that 0 is 500-3000 especially.
If it is too large exceeding 5,000, a polymer having no hydroxyl group is likely to be produced at the time of production, which makes it difficult to be effectively used for polyurethane, which may be a difficulty in industrial production.
The compounding amount is not particularly limited, but varies depending on the molecular structure, required water repellency, oil repellency, etc., and is usually 0.1 to 20% by weight, and especially 1 to 10% by weight. preferable.

[0008] The polymer diol (B) used in the present invention is selected from the group consisting of polyester, polycarbonate, polylactone and polyether. Its number average molecular weight is 500-3000, more preferably 7
The range of 00 to 2500 is selected. If it is less than 500, there is a tendency that the leather-like sheet-like material loses its flexibility or its hand feeling is reduced. If it exceeds 3000, it may be because the urethane group concentration is inevitably reduced,
Not only is it difficult to obtain a leather-like sheet having a good balance of cold resistance, heat resistance, and durability, but there is a problem in the industrial production of the polymer diol.

The polyester diol used in the present invention can be obtained, for example, by reacting a dibasic acid with a diol. Examples of the dibasic acid include aromatic 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. One of the basic acids or a combination thereof can be used. Among these, aliphatic dibasic acids, especially dibasic acids having a methylene chain length of 4 to 8, such as adipic acid, pimelic acid, speric acid, azelaic acid and sebacic acid, are more preferably used. As the diol, ethylene glycol which may be substituted with a lower alcohol, propylene glycol, butanediol, neopentyl glycol,
Aliphatic diols such as methylpentanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, dodecanediol, etc., cyclohexanediol, hydrogenated xylylene glycol, xylylene glycol, etc. One or a mixture of two or more aromatic diols and the like are used, and among them, aliphatic diols, especially butane diol, methyl pentane diol, hexane diol, heptane diol, methyl octane diol, carbon chain length such as nonane diol are used. One or a mixture of two or more of the aliphatic diols 4 to 9 is preferably used.

[0010] 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, propylene glycol, butanediol, neopentyl glycol, methylpentanediol, hexanediol, heptanediol, octanediol, nonanediol, which may be substituted with a lower alcohol,
Aliphatic diols such as decane diol and dodecane diol, cyclohexane diol, hydrogenated xylylene glycol, alicyclic diols such as xylylene glycol, and one or a mixture of two or more aromatic diols such as are used. Among them, aliphatic diols are preferable, and 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 are preferable. Used for

Polylactone diols include, for example, poly-ε-caprolactone diol, poly-trimethyl-ε
-Caprolactonediol, poly-β-methyl-δ-valerolactonediol and the like. Examples of the polyether diol include polytetramethylene glycol, polypropylene glycol, polyethylene glycol and the like.

The organic diisocyanate (C1) is, for example, diphenylmethane-4,4'-diisocyanate,
Aromatic diisocyanates such as 2,4- or 2,6-tolylene diisocyanate, meta- or para-phenylene diisocyanate, 1,5 naphthylene diisocyanate,
Non-aromatic diisocyanates such as isophorone diisocyanate, cyclohexane diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, and hydrogenated MDI are used. Of these, isophorone diisocyanate and 2,4- or 2,6-tolylene diisocyanate are preferred because the surface properties and feeling of the sheet obtained by coagulation with a non-solvent are good.

The intermediate diol (D) having a terminal OH substantially constitutes a substantially soft segment of the obtained polyurethane, and comprises the component (A), the polymer diol (B) and the organic diisocyanate (C1). And NC
It is obtained by reacting in a quantitative relationship such that the equivalent ratio of O / OH becomes 0.5 to 0.99. The equivalent ratio of NCO / OH is 0.5
If the amount is less than the above, the amount of the urethane bond incorporated into the intermediate diol having an OH end is substantially small, although it varies depending on the amount of the component (A), the molecular weight of the polymer diol (B), and the type of the organic diisocyanate (C1). Too much, or because the molecular weight is too small, the surface sliminess of leather-like sheet-like material, hand, flexibility, cold resistance, heat resistance is difficult to balance, the effect of the present invention is not sufficiently obtained . If the equivalent ratio of NCO / OH exceeds 0.99,
Although it depends on the blending amount of the component (A), the molecular weight of the polymer diol (B), and the type of the organic diisocyanate (C1), the amount of the urethane bond substantially incorporated into the intermediate diol having an OH terminal is too large. Is because the molecular weight of the intermediate diol (D) is too large, and it is difficult to balance the surface properties, feeling, flexibility, cold resistance and heat resistance of the leather-like sheet.

Examples of the low molecular diol (E) include ethylene glycol, propylene glycol, butanediol, neopentyl glycol, methylpentanediol, hexanediol, heptanediol, octanediol, nonanediol, which may be substituted with a lower alcohol. Alicyclic diols such as aliphatic diols such as decane diol and dodecane diol, cyclohexane diol, hydrogenated xylylene glycol, and the like, aromatic diols such as xylylene glycol, and further, one or a mixture of two or more kinds such as diethylene glycol. Among them, aliphatic diols, particularly ethylene glycol and butanediol, are suitably used in terms of balance of feeling, flexibility, cold resistance and heat resistance of the leather-like sheet.

The amount of the low molecular weight diol (E) is not particularly limited, but depends on its molecular structure, the amount of the component (A), the molecular weight of the polymer diol (B), the type of organic diisocyanate, and the NCO / OH equivalent ratio. Leather-like sheet usually having an equivalent ratio of (E) / (B) of 0.5 to 7.0, especially 1.0 to 5.5, relative to polymer diol (B). In many cases, it is suitable in terms of feeling, flexibility, cold resistance and heat resistance of the product.

The amount of diphenylmethane-4,4'-diisocyanate (C2) used is not particularly limited, but the viscosity of the polyurethane solution, the molecular weight of the fluorine-containing diol (A) and the polymer diol (B), and the fluorine-containing diol (A) , The NCO / OH equivalent ratio of the polymer diol (B) and the organic diisocyanate (C1), the reaction solvent, the fluorine contained diol (A), the polymer diol (B), and the water contained in the low molecular diol (D). But,
Normally, the equivalent ratio (NCO / OH) of NCO and fluorine-containing diol (A) from (C1) and (C2) and hydroxyl group from polymer diol (B) and low molecular weight diol (D) is 0.
It is preferably from 95 to 1.2, especially from 0.97 to 1.1.

A catalyst is not always necessary when the polymerization method used in the present invention is carried out, but catalysts used in the production of ordinary polyurethanes, for example, metal compounds such as titanium tetraisopropoxide, dibutyltin dilaurate and tin octate , Tetramethylbutanediamine,
Tertiary amines such as 1,4-diaza (2,2,2) bicyclooctane can be used.

As the solvent for the polyurethane obtained by the method used in the present invention, for example, commonly used solvents such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, toluene, ethyl acetate, methyl ethyl ketone and tetrahydrofuran are used. Polyurethane obtained by the method used in the present invention, various additives used in conventional polyurethane in use,
For example, phosphorus compounds, flame retardants such as halogen-containing compounds,
Antioxidants, ultraviolet absorbers, pigments, dyes, plasticizers, surfactants and the like can be added.

The fiber substrate is not particularly limited, and is selected from synthetic fibers such as 6-nylon, 6,6-nylon, 6,10-nylon, 12-nylon and other spinnable polyamides having an aromatic group. At least one kind of polyamide, polyethylene terephthalate, polyester such as polybutylene terephthalate, vinylon, polyacrylonitrile, etc., artificial fibers such as rayon, cupra, acetate, etc., or natural fibers such as silk, cotton, wool, hemp, etc. Any of cloth, woven cloth, non-woven cloth, and three-dimensionally entangled ultrafine fiber bundle having an average single denier of 0.1 denier or less can be used. Above all, average fineness of 3D entangled 0.1
A nonwoven fabric made of an ultrafine fiber bundle having a denier of not more than 0.005 to 0.1 denier can be suitably used.

The nonwoven fabric made of such an ultrafine fiber bundle is as follows:
It can be derived from a microfiber-generating fiber composed of two or more polymer components containing a known polyamide resin, polyester resin or the like as a microfiber component. Other polymers constituting the microfiber-generating fiber are not particularly limited, and differ in solubility or decomposability with respect to the microfiber component and the solvent or the decomposer, and are resins having a low affinity with the microfiber component.
Any resin having a lower melt viscosity under spinning conditions may be used, for example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylate ester copolymer, ethylene- α-olefin copolymer, polystyrene, styrene-isoprene copolymer, hydrogenated styrene-isoprene copolymer, sterene-butadiene copolymer, stellene-
It is selected from hydrogenated butadiene copolymers and the like. Such an ultrafine fiber generating fiber is prepared by mixing each component resin at a predetermined mixing ratio, dissolving in the same dissolving system, forming a mixed system and spinning, and dissolving in another dissolving system. The method of spinning by forming a mixed system by repeating joining-division a plurality of times at the head portion, and the method of spinning by dissolving with separate dissolving systems and defining the fiber shape at the spinneret portion, An ultrafine fiber-generating fiber is obtained in which the resin component to be ultrafine fibers is 40 to 80% by weight and the number of ultrafine fiber components in the fibers is 5 or more, preferably 50 to 800. If necessary, the microfiber-generating fiber may have a fineness of 2 to 15 denier through an ordinary fiber processing step such as drawing or heat setting, and an average fineness (calculated value) of the ultrafine fiber component of 0.2 denier or less, preferably 0.0
A fiber having a denier of 0.5 to 0.1 is used.

The microfiber-generating fibers are defibrated with a card and formed through a web to form a random web or a cross-wrap web, and the obtained fiber web is laminated to a desired weight and thickness. Next, the fiber web is subjected to a fiber entanglement treatment by a needle punch, a water jet, an air jet or the like by a conventionally known method to obtain a fiber entangled nonwoven fabric.

Next, the fiber-entangled nonwoven fabric is a composition solution obtained by adding a coagulation regulator, a release agent, a plasticizer, a stabilizer, an antioxidant, a light-proofing agent, a coloring agent, and the like, if necessary. Impregnated and / or coated on a fibrous substrate,
Wet or dry coagulation. In the case of ultrafine fiber-generating fibers, impregnation of the polyurethane composition liquid into the fiber entangled nonwoven fabric,
Prior to application, or after impregnation and application, the fibers are treated with a solvent of another resin constituting the fibers and a non-solvent of the fibers to obtain an ultrafine fiber structure. The amount of the polyurethane resin in the sheet is not particularly limited, but is preferably 10 to 60% by weight, and particularly preferably 15 to 45% by weight. If the amount of urethane used is small, it has a rather loose texture, and 1
If it is less than 0%, it becomes remarkable. If the amount of urethane is large, it tends to be hard or have a texture without swelling. 6
When the content is more than 0%, the tendency becomes remarkable.

The sheet-like material may be further provided with a porous or non-porous coating layer obtained from the above polyurethane, if necessary, on the surface to form a leather-like sheet with silver, or
At least one surface can be subjected to a brushing treatment to obtain a fiber-napped suede-like leather-like sheet. Further, if necessary, it can be slice-divided into an arbitrary thickness in the thickness direction at an arbitrary stage.

[0024]

The leather sheet of the present invention thus obtained is useful for various uses such as clothing, shoes, bags, furniture, vehicle interior materials, and miscellaneous goods. In the process of producing a leather-like sheet, the polyurethane resin obtained a leather-like sheet with good stain resistance and good texture without losing its desirable mechanical properties and workability.The mechanism of action is not clear. Reacts a fluorine-containing diol (A), a 500-3000 polymer diol (B) and an organic diisocyanate (C1) with N
A substantially terminal OH intermediate diol (D) and a low molecular weight diol (E) obtained by reacting in a quantitative relationship such that the equivalent ratio of CO / OH is 0.5 to 0.99; The soft segment and the hard segment constituting the polyurethane resin maintain a desirable micro-phase separation state while being impregnated with the polyurethane resin because the fluorine component has been introduced in the vicinity of the surface, thereby forming a leather as a coat layer. It is considered that the preferable properties as described above were imparted to the sheet material for use.

[0025]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto.
In the examples, parts and% relate to weight unless otherwise specified.

Example 1 A fluorine-containing diol (A) 160 having an average molecular weight of 1600 and an average molecular weight of 1600 obtained from a 1: 1 mixture of 2- (perfluorohexyl) ethyl methacrylate and butyl methacrylate and 3-mercapto-1,2-propanediol. Parts by weight, 300 parts by weight of polyhexylene carbonate having a number average molecular weight of 1000 as a polymer diol (B) and 600 parts by weight of polybutylene adipate having a number average molecular weight of 1,000, 2,4-tolylene diisocyanate and 2,4-tolylene diisocyanate as an organic diisocyanate (C1) 165 parts by weight of a mixture of 6-tolylene diisocyanate (80:20) (NCO / OH = 0.
95), and 5370 parts by weight of DMF are charged into the reactor,
The reaction was carried out at a predetermined temperature under a nitrogen stream for a predetermined time to obtain an intermediate. After confirming that the isocyanate group was lost, the weight average molecular weight (in terms of polystyrene) of the intermediate was measured using GPC and found to be 66,000.

DMF of the intermediate diol (D) obtained above
To the solution, 106 parts by weight of ethylene glycol and 459 parts by weight of diphenylmethane-4,4'-diisocyanate (C2) were added and reacted as a low molecular diol (E) to obtain a polyurethane solution having a weight average molecular weight of 390,000. To 100 parts by weight of the obtained polyurethane solution, 92 parts by weight of DMF,
1.5 parts by weight of Chris Bon Assister SD7 (trademark: Dainippon Ink Co., Ltd.), Chris Bon Assister SD14
(Trademark: Dai Nippon Ink Co., Ltd.)
An impregnating liquid was used.

On the other hand, a web is formed using staple fibers of ultrafine fiber generating type fibers (6-nylon is an ultrafine fiber component) obtained by melt-spinning 50 parts by weight of 6-nylon and 50 parts by weight of highly fluid polyethylene. It was made into a needle punch entangled nonwoven fabric. This impregnated nonwoven fabric was impregnated with the above impregnating liquid, and then poured into a 25% aqueous solution of DMF for coagulation. Then, the mixture was treated in hot toluene to dissolve and remove the polyethylene component, thereby obtaining a sheet having a thickness of 1.4 mm. This sheet was divided into two parts, and the divided surfaces were buffed with sandpaper to a thickness of 0.56 mm. Further, the surface at the time of solidification was treated with an emery buffing machine to form a napped surface. The above-mentioned sheet having a raised surface was cut and attached to an armchair of an office chair as a stain resistance test. The sheet was tested for 4 months from June to September, and its dirt condition was observed. However, the advantages of the present invention are clear.

Comparative Example 1 The same raw material composition as in Example 1 was charged all at once into a reactor and reacted under a nitrogen stream at a predetermined temperature for a predetermined time to obtain a polyurethane solution having a weight average molecular weight of 370,000. Using the obtained polyurethane solution, an impregnation liquid was prepared in the same manner as in Example 1. The impregnated nonwoven fabric of Example 1 was impregnated with the above impregnating solution, and then poured into a 25% aqueous solution of DMF to coagulate. Then, the mixture was treated in hot toluene to dissolve and remove the polyethylene component, thereby obtaining a sheet having a thickness of 1.4 mm. The obtained sheet-like material was hard and extremely poor in touch, and was hardly a leather-like sheet. As described above, when the polyurethane obtained without passing through the intermediate (D) obtained by reacting the fluorine-containing diol (A), the polymer diol (B), and the organic diisocyanate (C1) is used, a sheet having a good texture is used. Is not obtained, and the superiority of the technology via the intermediate (D) of the present invention is clear in comparison with Example 1.

Comparative Example 2 In Example 1, a mixture (weight ratio 80:20) of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate was used as the organic diisocyanate (C1).
5 parts by weight (NCO / OH = 0.20) and DMF
An intermediate was obtained in the same manner except that the amount was changed to 540 parts by weight. After confirming that the isocyanate group had disappeared, the weight average molecular weight (in terms of polystyrene) of the intermediate was measured using GPC and found to be 12,000. To the DMF solution of the intermediate diol (D) obtained above, 106 parts by weight of ethylene glycol and 646 parts by weight of diphenylmethane-4,4'-diisocyanate (C2) were added as the low molecular weight diol (E), and the mixture was reacted. A polyurethane solution having an average molecular weight of 380,000 was obtained. Using the obtained polyurethane solution, an impregnation liquid was prepared in the same manner as in Example 1.

The impregnated nonwoven fabric used in Example 1 was impregnated with the above impregnating solution, and then poured into a 25% aqueous solution of DMF.
Coagulation took place. Then, the mixture was treated in hot toluene to dissolve and remove the polyethylene component, thereby obtaining a sheet having a thickness of 1.4 mm. The obtained sheet-like material was hard and extremely poor in touch, and was hardly a leather-like sheet. Thus, the fluorine-containing diol (A), the polymer diol (B) and the organic diisocyanate (C1) are
When the polyurethane obtained via the intermediate (D) obtained by reacting with O / OH of 0.2 is used, a sheet having a good texture cannot be obtained, and the fluorine-containing diol (A) and the polymer diol of the present invention are not obtained. (B), an intermediate (D) obtained by reacting an organic diisocyanate (C1) with an NCO / OH of 0.5 or more
The advantage of the technology passing through is clear in comparison with the first embodiment.

Example 2 1: 1 mixture of 2- (perfluoro-3-methylbutyl) ethyl methacrylate and methyl methacrylate and 3
A fluorine-containing diol (A) 400 having an average molecular weight of 2000 and obtained from mercapto-1,2-propanediol;
Parts by weight, number average molecular weight 2 as polymer diol (B)
000 of polyhexylene carbonate, 500 parts by weight of polybutylene adipate having a number average molecular weight of 2000, 500 parts by weight of polytetramethylene glycol having a number average molecular weight of 2000, and organic diisocyanate (C
188 parts by weight of diphenylmethane-4,4'-diisocyanate (NCO / OH = 0.75) as 1), and D
MF10610 parts by weight was charged into a reactor, and reacted at a predetermined temperature and a predetermined time under a nitrogen stream to obtain an intermediate. After confirming that the isocyanate group has disappeared, the intermediate is subjected to GPC.
Was 41,000 when the weight average molecular weight (in terms of polystyrene) was measured.

DMF of the intermediate diol (D) obtained above
To the solution, 248 parts by weight of ethylene glycol and 1100 parts by weight of diphenylmethane-4,4'-diisocyanate (C2) were added and reacted as a low molecular diol (E) to obtain a polyurethane solution having a weight average molecular weight of 410,000. 19 parts by weight of DMF was added to 100 parts by weight of the obtained polyurethane solution,
1.5 parts by weight of Chris Bon Assister SD7 (trademark: Dainippon Ink Co., Ltd.), Chris Bon Assister SD14
(Trademark: Dai Nippon Ink Co., Ltd.)
A coating solution was used. After impregnating the entangled nonwoven fabric of Example 1 with the impregnating solution of Example 1, the above coating solution was applied to a thickness of 0.5 mm.
And then poured into a 25% aqueous solution of DMF to coagulate. Then, the resultant was treated in hot toluene to dissolve and remove the polyethylene component, thereby obtaining a 2.2 mm thick sheet material with a good texture and a silver surface. The obtained sheet was subjected to a contamination test in the same manner as in Example 1. As a result, the sheet was hardly contaminated, and the superiority of the present invention is clear.

Comparative Example 3 In Example 2, 256 parts by weight of diphenylmethane-4,4'-diisocyanate (NCO / OH = 1.0
An intermediate was obtained in the same manner except that 2) and 10640 parts by weight of DMF were used. After confirming that the isocyanate group had disappeared, the weight average molecular weight (in terms of polystyrene) of the intermediate was measured using GPC and found to be 240,000. As a low molecular diol (E), 24 g of ethylene glycol was added to the DMF solution of the intermediate diol (D) obtained above.
Eight parts by weight and 1043 parts by weight of diphenylmethane-4,4'-diisocyanate (C2) were added and reacted to obtain a polyurethane solution having a weight average molecular weight of 420,000.

A sheet having a silver surface was obtained in the same manner as in Example 2 except that the polyurethane solution obtained above was used. However, the foam of the silver surface was poor, hard, and had a poor texture. Thus, the fluorine-containing diol (A), polymer diol (B), and organic diisocyanate (C1)
When the polyurethane obtained via the intermediate (D) obtained by reacting with CO / OH of 1.02 is used, a sheet having a good texture cannot be obtained, and the fluorine-containing diol (A) of the present invention,
Polymer diol (B), organic diisocyanate (C
The superiority of the technology via intermediate (D) obtained by reacting 1) with NCO / OH of 0.99 or less is clear in comparison with Example 2.

Example 3 Fluorine-containing diol (A) 320 having an average molecular weight of 1600 and obtained from 3-mercapto-1,2-propanediol and a 1: 1 mixture of 2- (perfluorohexyl) ethyl methacrylate and butyl methacrylate (A) 320 Parts by weight, 600 parts by weight of polyhexylene carbonate having a number average molecular weight of 2,000 as the polymer diol (B) and 1000 parts by weight of polybutylene adipate having a number average molecular weight of 2,000, and diphenylmethane as the organic diisocyanate (C1).
200 parts by weight of 4,4'-diisocyanate (NCO / O
H = 0.80) and 9440 parts by weight of DMF were charged into a reactor, and reacted at a predetermined temperature under a nitrogen stream for a predetermined time to obtain an intermediate. After confirming that the isocyanate group was lost, the weight average molecular weight (in terms of polystyrene) of the intermediate was measured using GPC and found to be 49,000.

DMF of the intermediate diol (D) obtained above
186 parts by weight of ethylene glycol as low molecular diol (E) and 841 parts by weight of diphenylmethane-4,4'-diisocyanate (C2) were added and reacted to obtain a polyurethane solution having a weight average molecular weight of 380,000. An impregnating liquid was prepared in the same manner as in Example 1 using the obtained polyurethane solution. The entangled nonwoven fabric used in Example 1 was impregnated with the above impregnating liquid, and subsequently poured into a 25% aqueous solution of DMF to coagulate. Then, it was treated in hot toluene to dissolve and remove the polyethylene component to obtain a sheet. Although the obtained sheet was slightly hard, it was practically sufficient,
When a stain resistance test was carried out on the sheet-like material having raised hairs in the same manner as in Example 1, a sheet-like material excellent in stain resistance was obtained, and the superiority of the present invention is clear.

Comparative Example 5 A fluorine-containing diol (A) having an average molecular weight of 1600 and obtained from 3-mercapto-1,2-propanediol and a 1: 1 mixture of 2- (perfluorohexyl) ethyl methacrylate and butyl methacrylate was prepared. Without using
750 parts by weight of polyhexylene carbonate having a number average molecular weight of 2,000 as polymer diol (B) and 1250 parts by weight of polybutylene adipate having a number average molecular weight of 2,000
200 parts by weight of diphenylmethane-4,4'-diisocyanate (NCO /
OH = 0.8) and 9684 parts by weight of DMF were charged into a reactor and reacted under a nitrogen stream at a predetermined temperature for a predetermined time to obtain an intermediate. After confirming that the isocyanate group had disappeared, the weight average molecular weight (in terms of polystyrene) of the intermediate was measured using GPC and found to be 53,000.

As a low molecular diol (E), ethylene glycol 186 was added to the DMF solution of the intermediate diol obtained above.
842 parts by weight of diphenylmethane-4,4'-diisocyanate (C2) were added and reacted to obtain a polyurethane solution having a weight average molecular weight of 390,000. Using the obtained polyurethane solution, an impregnating liquid was prepared in the same manner as in Example 1 to obtain a sheet having a raised surface. When the obtained sheet was subjected to a stain resistance test under the same conditions as in Example 1, the sheet was dark and had a poor appearance. In comparison with Example 3, the fluorine-containing diol (A) of the present invention was used. The effect is obvious.

[0040]

The leather-like sheet of the present invention uses a polyurethane resin which is excellent in various physical properties such as mechanical properties and durability, excellent in workability, and excellent in antifouling property. It is a leather-like sheet excellent in flexibility, cold resistance, heat resistance, durability, and stain resistance, and is useful for various uses such as clothing, shoes, bags, furniture, vehicle interior materials, and miscellaneous goods.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI // C08G 18/65 C08G 18/65 C08L 75:04 D06M 15/568

Claims (1)

(57) [Claims] 1. A fluorine-containing diol (A) obtained by radical polymerization of a perfluoroalkyl ester of acrylic acid and / or methacrylic acid in the presence of a compound containing two hydroxyl groups and one thiol group, Number average molecular weight selected from the group consisting of polyester, polycarbonate, polylactone, and polyether is 500 to 300.
0 of the polymer diol (B) and the organic diisocyanate (C1) in an equivalent ratio of NCO / OH of 0.5 to 0.1.
By reacting an intermediate diol (D) having a terminal OH obtained by reacting with a quantitative relationship such that it becomes 99, a low molecular diol (E), and diphenylmethane-4,4'-diisocyanate (C2). A leather-like sheet having good stain resistance, comprising the obtained polyurethane and a fiber structure.