CN100484981C - Sheetlike products and interior finishing materials - Google Patents

Abstract

The present invention provides a sheet-like article, which is composed of a non-woven fabric formed by entangled ultrafine fibers having a single fiber fineness of 0.5 dtex or less and an elastic resin adhesive mainly composed of polyurethane. In the sheet-like article, the polyurethane is a polycarbonate-based polyurethane having a polycarbonate skeleton represented by the following general formulas (1) and (2), and has a gel point of 2.5 ml or more and less than 6 ml. In the formulas, _R1 and _R2 are aliphatic hydrocarbon groups having 7 to 11 carbon atoms and may be the same or different. In addition, n and m are positive integers. When _R1 and _R2 are different, the copolymer is a block copolymer or a random copolymer. In the formulas, _R3 and _R4 are aliphatic hydrocarbon groups having 3 to 6 carbon atoms and may be the same or different. In addition, x and y are positive integers. When _R3 and _R4 are different, the copolymer is a block copolymer or a random copolymer.

Description

Sheets and interior trim materials

technical field

The present invention relates to sheets, in particular to napped leather-like sheets.

Background technique

On the surface of the sheet formed by impregnating polyurethane resin in the base material made of fibers, by using sandpaper or the like to roughen the fibers, a napped leather-like sheet of imitation suede or imitation sanded cowhide can be obtained. is well known. The properties of the intended leather-like sheet can be arbitrarily broadly designed by combining a base material composed of fibers and a polyurethane resin. For example, Patent Document 1 discloses that by adopting a polyurethane resin using polytetramethylene glycol, an organic diisocyanate, and a diol chain extender, it is possible to obtain an Disadvantaged, artificial leather-like with an extremely soft hand.

On the other hand, the brushed imitation leather sheet has an appearance and surface similar to natural leather, and can be seen to have advantages such as uniformity and dyeing fastness that natural leather does not have. The scale of use is also expanding in applications that can be used for a long period of 5 to 10 years, such as the skin of furniture such as sofas and the skin of automobiles.

However, the polyether-based polyurethane resin using polytetramethylene glycol described in Patent Document 1 is prone to aging due to the action of ultraviolet rays and heat, so the surface fibers pill and fall off during use. , or fluffing occurs, and there is a problem that it cannot withstand long-term use. In addition, polyester-based polyurethane resin is also a polyurethane that can be used well for imitation leather sheets. It has good light resistance when exposed to ultraviolet rays, etc., but since the ester bond will deteriorate through hydrolysis, there will be surface defects in long-term use. Fiber pilling, the same problem of pilling.

Patent Document 2 discloses that polycarbonate-based polyurethane obtained by reacting polycarbonate polyol, alicyclic polyisocyanate, and aromatic polyisocyanate has high durability in furniture, vehicle sheets, etc. Polyurethane resins useful in However, when the polycarbonate-based polyurethane resin using polyhexamethylene carbonate described here is used as a resin impregnated into a nonwoven fabric formed by entanglement of ultrafine fibers, the sheet-like The handle feels as rough as plastic. In particular, when the surface is napped with sandpaper, since the polyurethane is too hard, the surface nap is short and rough, and it is extremely difficult to obtain a good quality with a beautiful nap.

In Patent Document 3, for the purpose of achieving both nap quality and durability such as light resistance and hydrolysis resistance, a napped leather-like sheet is disclosed. The sheet uses: polycarbonate diol, mainly Polyhexamethylene carbonate diol is 30 to 90% by weight, and polyether diol or polyester diol is used in combination, polycarbonate/polyether-based polyurethane resin, polycarbonate/polyester-based polyurethane resin ,. However, when the ratio of polycarbonate diol is less than 70% by weight, durability becomes insufficient due to aging of the polyether component or polyester component. On the other hand, when the ratio of polycarbonate diol is 70% by weight When the weight % is more than that, the polyurethane becomes too hard, and when the surface is ground with sandpaper, etc., the nap on the surface becomes short and rough, and it is difficult to obtain a napped leather-like sheet satisfying both the nap quality and durability.

In addition, in so-called synthetic leather, which is a leather-like sheet coated or pasted with a resin layer on a fibrous base material, it is known that a polycarbonate-based polyurethane resin is used in the resin layer for the purpose of improving durability. . Mainly for the purpose of improving the texture of synthetic leather, various proposals have been made regarding the polycarbonate-based polyurethane resin used for the resin layer.

For example, Patent Document 4 discloses: a polyurethane resin using a copolycarbonate diol derived from 1,6-hexanediol and 1,5-pentanediol, a polyurethane resin using 1,6-hexanediol and 1 , Polyurethane resin of copolycarbonate diol derived from 4-butanediol; Patent Document 5 discloses: Polyurethane using polycarbonate diol derived from 2-methyl-1,8-octanediol Resin; Disclosed in Patent Document 6: polyester diol derived from alkanediol and dicarboxylic acid with carbon number of 5 to 6, and polyester diol derived from alkanediol with carbon number of 8 to 10 Polyester/polycarbonate-based polyurethane resin in which polycarbonate diol is used in combination; Patent Document 7 discloses that polycarbonate diol and polyether diol derived from alkane diol having 8 to 10 carbon atoms are used in combination Polycarbonate/polyether polyurethane resin.

These polyurethane resins are suitable for use as a resin impregnated into a non-woven fabric made of ultrafine fibers and made to exist in the internal space of the non-woven fabric. In the case of a roughened leather sheet obtained by shaving the surface and roughening the surface fibers, for example, the copolymerized polycarbonate-based polyurethane resin with 4 to 6 carbon atoms described in Patent Document 4 cannot be obtained. The softening effect of the degree of grinding results in a rough surface with short naps on the surface, so it is extremely difficult to obtain a good grade with beautiful naps. In addition, since the polycarbonate-based polyurethane resin derived from 2-methyl-1,8-octanediol described in Patent Document 5 uses a long-chain alkylene glycol, after being impregnated into a nonwoven fabric, In the case of wet coagulation, the coagulation speed is remarkably fast, and the foaming of the polyurethane inside the nonwoven fabric is large and coarse, and in addition, partial foaming results in poor results, and there is the following problem. In some cases, only flakes with very poor nap quality due to uneven length of nap on the surface can be obtained. In addition, when the surface of the resulting sheet was rubbed with a brush or the like, many fibers fell off, causing a problem in abrasion resistance. In the polyurethane resins described in Patent Documents 6 and 7, polyester diol and polyether diol are used in combination. From the viewpoint of hydrolysis resistance or light resistance, it is impossible to improve the napped leather-like sheet for a long time. Durability during use, especially the problem of pilling and pilling of surface fibers.

In addition, the techniques described in these Patent Documents 4 to 7 are mainly aimed at improving the texture of the polyurethane resin layer provided on the base material such as the smooth feel, surface smoothness, stickiness, and surface physical properties of cracks. The satisfactory nap length of microfibers and the beauty brought by napping are not considered at all in the case of the presence of polyurethane resin in the internal space of the non-woven fabric, and the improvement of the abrasiveness of sandpaper, etc. Appearance and supple surface touch, soft hand.

On the other hand, Patent Document 8 discloses a flexible fibrous sheet using thermoplastic polyurethane having a polysiloxane segment in the main chain and/or side chain and a polyurethane-based multicomponent sheet suitable for its production. fiber. . In the case where the surface of the sheet made of fibers is ground with sandpaper or the like, the polyurethane is contained in the ultrafine fiber bundle, and the polyurethane is present bonded to each single fiber of the ultrafine fiber, so the fiber The cutting of the sheet is obvious, and it is not enough to obtain a beautiful appearance brought by napping. At the same time, the softness and feel of the sheet cannot meet the requirements.

In addition, Patent Document 9 discloses a sheet-like article and a method for producing the sheet-like article in which a polysiloxane is present in a state where there is substantially no fiber bundle of ultrafine fibers constituting a nonwoven fabric. Polyurethane resin obtained by polyol modification, the polysiloxane polyol has 5-30% by weight of dimethylsiloxane structural units relative to the polymer diol component. However, polysiloxane polyols only describe a dimethylpolysiloxane structure having hydroxyl groups at both ends, and a polyurethane resin obtained by using this polysiloxane polyol having hydroxyl groups at both ends becomes A block polymer with dimethyl polysiloxane chains introduced into the main chain. In the case of napping a sheet impregnated with polyurethane resin mainly composed of polycarbonate modified with polysiloxane polyols having hydroxyl groups at both ends, through normal grinding, in order to obtain ideal The length of nap, beautiful appearance, the content of polysiloxane polyol should be at least 10% by weight relative to the polymer diol mainly composed of polycarbonate diol, but when the polyurethane resin contains actually When the amount of polysiloxane polyol is more than 10% by weight, the light resistance of the polyurethane resin deteriorates remarkably, and pilling and pilling of fibers tend to occur, making it impossible to obtain a sheet with satisfactory durability.

As mentioned above, in the prior art, it is extremely difficult to stably obtain a napped leather-like sheet excellent in handle, nap quality, and durability.

Patent Document 1: JP-A-59-192779

Patent Document 2: JP-A-3-244619

Patent Document 3: JP-A-2002-30579

Patent Document 4: Japanese Unexamined Patent Publication No. 5-5280

Patent Document 5: JP-A-2-33384

Patent Document 6: JP-A-4-300368

Patent Document 7: JP-A-5-9875

Patent Document 8: Japanese Unexamined Patent Publication No. 4-202861

Patent Document 9: JP-A-7-150478

Contents of the invention

The object of the present invention is, in view of the background of the prior art, to provide a napped imitation leather sheet, which has both the beautiful appearance brought by napping and the appearance of natural leather. High durability with less texture, less fiber shedding, pilling, and pilling during long-term use.

In order to solve the above-mentioned problems, the present invention has the following configurations.

That is, the sheet-like article of the present invention is a sheet-like article made of a non-woven fabric formed by intertwining ultrafine fibers with a single fiber fineness of 0.5 dtex or less and an elastic resin binder mainly composed of polyurethane. In the sheet, the polyurethane is a polycarbonate-based polyurethane having a polycarbonate skeleton represented by the following general formulas (1) and (2), and has a gel point of 2.5 ml or more but less than 6 ml.

(In the formula, R ₁ and R ₂ are aliphatic hydrocarbon groups with 7 to 11 carbon atoms, which can be the same or different. In addition, n and m are positive integers. When R ₁ and R ₂ are different, they are embedded segmental copolymerization or random copolymerization.)

(In the formula, R ₃ and R ₄ are aliphatic hydrocarbon groups with ₃ to ₆ carbon atoms, which can be the same or different. In addition, x and y are positive integers. When R ₃ and R ₄ are different, they are embedded block copolymerization or random copolymerization.) Further preferably, the polyurethane is a polyurethane having a side chain having a polyorganosiloxane skeleton represented by the following general formula (3).

(In the formula, _R5 and _R6 are aliphatic hydrocarbon groups or aryl groups, which can be the same or different. In addition, p is a positive integer.)

Moreover, the interior material of this invention is comprised using the said sheet-like thing.

Invention effect

According to the present invention, it is possible to provide a napped leather-like sheet which has a beautiful appearance due to napping and is also excellent in durability such as hydrolysis resistance and light resistance.

Detailed ways

The sheet-like object of the present invention is composed of a non-woven fabric formed by intertwining superfine fibers with a single fiber fineness of 0.5 dtex or less and an elastic resin adhesive mainly composed of polyurethane.

As raw materials for ultrafine fibers constituting nonwoven fabrics, polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polytrimethylene terephthalate, nylon 6, Melt-spinnable thermoplastic resin such as polyamide such as nylon 66. Among them, polyester is preferably used from the viewpoint of strength, dimensional stability, and light resistance. In addition, microfibers of different raw materials may be mixed with the nonwoven fabric.

It is important that the single fiber fineness of the ultrafine fibers constituting the nonwoven fabric be 0.5 dtex or less from the viewpoint of the softness of the sheet and the nap quality. More preferably, it is 0.3 dtex or less, and still more preferably, it is 0.2 dtex or less. On the other hand, it is preferably 0.005 dtex or more, more preferably 0.01 dtex or more, from the viewpoint of color development after dyeing, dispersibility of bundled fibers during napping treatment by buffing, and ease of fiber opening. The single fiber fineness mentioned here is to cut the obtained sheet in the thickness direction, observe the cross-section with a scanning electron microscope (SEM), measure the fiber diameter of the ultrafine fiber at any 100 positions, and calculate its average value, Calculated from the specific gravity of the thermoplastic resin used for ultrafine fibers.

As a method of obtaining ultrafine fibers, it is preferable to use ultrafine fiber-generating fibers. Microfiber-generating fibers can be island-in-the-sea composite fibers, stripped composite fibers, multi-layer composite fibers, etc. The island-in-the-sea composite fibers use two-component thermoplastic resins with different solubility in solvents as sea components.・The island component is dissolved and removed only the sea component by using a solvent, etc., and the island component is used as a composite fiber of ultrafine fibers. It is a composite fiber that is alternately arranged in a radial or layered manner, and each component is separated by peeling, and spun into ultrafine fibers.

Non-woven fabrics, non-woven fabrics in which each single fiber of microfibers are entangled, and non-woven fabrics in which fiber bundles of microfibers are entangled can be used, but from the viewpoint of the strength and feel of the sheet , preferably a non-woven fabric formed by intertwining fiber bundles of microfibers. From the viewpoint of softness and texture, a nonwoven fabric having moderate voids between microfibers inside the fiber bundle is particularly preferable. A non-woven fabric composed of fiber bundles of such microfibers entangled can be obtained by preliminarily entangled ultrafine fiber-generating fibers and then generating ultrafine fibers. In addition, a nonwoven fabric having moderate voids between ultrafine fibers inside the fiber bundle can be obtained by using an island-in-the-sea type composite fiber capable of forming an island by removing the sea component. Island-in-the-sea type composite fiber with moderate gaps between the components, that is, between the microfibers inside the fiber bundle.

For the sea-island type composite fiber, it is possible to use: using a spinneret for sea-island type composite, the polymer interarrangement method in which the resins of the two components of the sea and the island are arranged and spun; and, the sea-island two-component resin A mixed spinning method of performing melt mixing and spinning, etc., but from the viewpoint of obtaining ultrafine fibers of uniform fineness, sea-island composite fibers obtained by a polymer mutual array method are preferable.

In particular, regarding the uniformity of fineness, it is preferable that the fineness CV in the fiber bundle is 10% or less. The fineness CV mentioned here is a value obtained by dividing the standard deviation of the fineness of the fibers constituting the fiber bundle by the average fineness in the bundle in percentage (%), and the smaller the value, the more uniform it is. By setting the fineness CV to be 10% or less, it is possible to obtain a sheet-like product having a fine napped appearance on the surface of the sheet and uniform and favorable dyeing.

As the sea component of the island-in-the-sea type composite fiber, copolyester, polylactic acid, etc. which use polyethylene, polypropylene, polystyrene, sodium sulfoisophthalic acid, polyethylene glycol, etc. as a copolymerization component can be used. As a solvent for dissolving the sea component, organic solvents such as toluene and trichlorethylene can be used when the copolymer component is polyethylene, polypropylene, or polystyrene; The sea-island composite fiber can be removed by soaking the sea-island type composite fiber in a solvent using an alkaline aqueous solution such as sodium hydroxide, followed by squeezing.

The cross-sectional shape of the microfiber can be a common circular cross-section, or a special-shaped cross-section such as an oval, flat, triangular, fan-shaped, or cross-shaped cross-section.

The non-woven fabric constituting the sheet-like article of the present invention may be any of short-fiber non-woven fabrics and long-fiber non-woven fabrics, but short-fiber non-woven fabrics are preferable when feeling and quality are important. In addition, a woven or knitted fabric may be inserted inside the nonwoven fabric for the purpose of improving strength or the like.

As a method of entanglement of ultrafine fibers to obtain a nonwoven fabric, a method of entanglement by needle punching or hydroentangling can be used.

It is important that the polyurethane used as the main component of the elastic resin adhesive used in the present invention is a carbonate-based polyurethane having a polycarbonate skeleton represented by the following general formulas (1) and (2).

(In the formula, R ₁ and R ₂ are aliphatic hydrocarbon groups with 7 to 11 carbon atoms, which can be the same or different. In addition, n and m are positive integers. When R ₁ and R ₂ are different, they are embedded segmental copolymerization or random copolymerization.)

(In the formula, R ₃ and R ₄ are aliphatic hydrocarbon groups with 3 to 6 carbon atoms, which can be the same or different. In addition, x and y are positive integers. When R ₃ and R ₄ are different, they are embedded segmental copolymerization or random copolymerization.)

That is to say, by having the polycarbonate skeleton of the long-chain aliphatic hydrocarbon group with the carbon number shown in general formula (1) being 7～11 at the same time and having the carbon atom number shown in general formula (2) as Different structures of polycarbonate skeletons with short-chain aliphatic hydrocarbon groups of 3 to 6, polyurethane tends to become an amorphous structure, and achieves a suitable hardness when grinding with sandpaper, etc., and can obtain very good surface fiber napping.

R ₁ and R ₂ shown in the above-mentioned general formula (1), R ₃ and R ₄ shown in the above-mentioned general formula (2) may be the same aliphatic hydrocarbon groups or different aliphatic hydrocarbon groups respectively, but when When the aliphatic hydrocarbon groups are respectively different, the polyurethane is more likely to have an amorphous structure, and the flexibility and nap quality of the obtained sheet tend to be good, so it is preferable.

In addition, the polycarbonate skeleton represented by the above-mentioned general formulas (1) and (2) can be any copolymerization of block copolymerization or random copolymerization, but from the point of view that polyurethane is more likely to become an amorphous structure, random copolymerization is preferred. copolymerization.

Similarly, it is more preferable that R ₁ , R ₂ , R ₃ , and R ₄ are all four different aliphatic hydrocarbon groups from the viewpoint of the softness and nap quality of the sheet. Particularly preferably, at least one of _R1 and _R2 , and at least one of _R3 and _R4 is an aliphatic hydrocarbon group branched by a methyl group or an ethyl group.

The polyurethane used in the present invention, if it is at least one polycarbonate skeleton having a long-chain aliphatic hydrocarbon group with 7 to 11 carbon atoms, and a short-chain aliphatic hydrocarbon group with 3 to 6 carbon atoms The polyurethane having at least one polycarbonate skeleton may be polyurethane having five or more kinds of carbonate skeletons.

More preferably, the polyurethane is a polyurethane having a side chain having a polyorganosiloxane skeleton represented by the following general formula (3).

(In the formula, R ₅ and R ₆ are aliphatic hydrocarbon groups or allyl groups, which may be the same or different. And, p represents a positive integer.)

Finally, the sheet of the present invention can be suitably used as a napped leather-like sheet having microfibers napped on at least one side thereof. The napping treatment can be carried out by grinding with sandpaper, a roller sander, etc., but usually in order to obtain a good surface fiber napping, it is preferable to add a lubricant such as polysiloxane latex before the napping treatment. .

However, when a lubricant is used, the grinding dust generated from the flakes due to grinding tends to cause significant accumulation on the sandpaper, which tends to cause early clogging and the like, which tends to deteriorate production efficiency.

On the other hand, by making this polyurethane a polyurethane having a side chain containing a polyorganosiloxane skeleton represented by the above-mentioned general formula (3), it is not necessary to provide a lubricant such as polysiloxane latex before the napping treatment, and it is also possible to Fiber napping with an extremely good surface can be obtained, and deterioration of productivity during napping can also be prevented.

R ₅ and R ₆ represented by the above general formula (3) are aliphatic hydrocarbon groups or aryl groups, which may be the same or different, but from the aspect of production cost, it is preferable that both R ₅ and R ₆ are methyl groups. In addition, p is a positive integer. It is preferable that p is 100-300 in order to adjust the number average molecular weight (Mn) of the polysiloxane polyol (C) mentioned later in the preferable range. The polyorganosiloxane skeleton is necessary to obtain a beautiful nap shape. When it is contained in a large amount, the light resistance of polyurethane will deteriorate significantly, and because of deterioration, pilling and pilling of the fiber will easily occur, and the nap cannot be achieved. The target durability performance of a leather sheet is modified, but by including the skeleton in the side chain, a beautiful appearance and quality can be obtained even in a small amount, so an imitation leather having both beautiful quality and durability can be obtained Flakes.

The polyurethane, more specifically, is preferably obtained by having a polycarbonate diol (A) having a hydroxyl group at both ends of a molecular chain having a polycarbonate skeleton represented by the above-mentioned general formula (1), and having the above-mentioned general formula ( 2) The polycarbonate diol (B) having hydroxyl groups at both ends of the molecular chain of the polycarbonate skeleton shown in the polyurethane obtained by reacting with an organic diisocyanate and a chain extender is more preferably obtained by further containing only A polyurethane obtained by reacting a polysiloxane polyol (C) having two hydroxyl groups at one end of a molecular chain having a polyorganosiloxane skeleton represented by the above general formula (3).

The polycarbonate skeleton mentioned in the present invention is a skeleton that forms a polymer chain linked by a carbonate bond, and the so-called polycarbonate diol is a polycarbonate having one hydroxyl group at both ends of the polymer chain. carbonate diol. Polycarbonate diol can be produced by transesterification reaction of alkylene glycol and carbonate, reaction of phosgene or chloroformate and alkylene glycol, or the like.

As an alkylene glycol for obtaining a polycarbonate diol (A) having a polycarbonate skeleton having a long-chain aliphatic hydrocarbon group having 7 to 11 carbon atoms represented by the general formula (1), 1, 7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol and other linear alkylene glycols, and 2-methyl-1,8-octanediol , 2,7-dimethyl-1,8-octanediol, 2,8-dimethyl-1,9-nonanediol and other branched alkylene glycols. Particularly preferably, the copolycarbonate diol obtained from straight-chain alkylene glycol and branched-chain alkylene glycol obtained from 1,9-nonanediol and 2-methyl-1,8-octanediol, etc., from From the softness and easiness of grinding with sandpaper or the like when making a napped leather-like sheet, it tends to obtain a good nap quality, so it is preferable.

1,3- Propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol and other linear alkylene glycols, and propylene glycol, neopentyl glycol, 3-methyl-1,5- Branched alkylene glycols such as pentanediol. Particularly preferably, the copolycarbonate diol obtained from linear alkylene glycol and branched chain alkylene glycol obtained from 1,6-hexanediol and 3-methyl-1,5-pentanediol, etc., from From the softness and easiness of grinding with sandpaper or the like when making a napped leather-like sheet, it tends to obtain a good nap quality, so it is preferable. As the carbonate used in the transesterification reaction, diethyl carbonate, diphenyl carbonate, etc. may, for example, be mentioned.

The number average molecular weight (Mn) of the polycarbonate diols (A) and (B) is preferably 500 to 3,000, more preferably 1,500 to 2,500. When the number average molecular weight is 500 or more, it is possible to prevent the texture from becoming hard, and when the number average molecular weight is 3,000 or less, the strength as polyurethane can be maintained.

Polysiloxane polyol (C) is not a polysiloxane polyol having one hydroxyl group at each end of the polymer chain, but a polysiloxane having two hydroxyl groups at only one end of the polymer chain Polyol. By defining in this way, a polyurethane having a polyorganosiloxane skeleton not in a straight chain but in a side chain can be obtained.

As number average molecular weight (Mn) of polysiloxane polyol (C), 500-30,000 are preferable. When the number average molecular weight is less than 500, the napping of the sheet tends to be shortened when the napping treatment is carried out with sandpaper or the like. On the contrary, when it exceeds 30,000, the phase of polysiloxane polyol (C) and other polyols tends to be shortened. Solubility deteriorates, and it tends to be difficult to obtain stable polyurethane. The number average molecular weight is more preferably in the range of 5,000 to 25,000, and particularly preferably in the range of more than 10,000 to 20,000. In particular, when using a polysiloxane polyol having a number average molecular weight of more than 10,000 but not more than 20,000, even if a small amount is used, a leather-like sheet excellent in both nap quality and appearance can be obtained.

The ratio of the polysiloxane polyol (C) to the sum of the polycarbonate diols (A) and (B) is preferably 0.1% by weight or more but less than 5% by weight. More preferably, it is 0.5 to 4 weight%, More preferably, it is 1 to 3 weight%. By making the ratio of the polysiloxane polyol (C) 0.1% by weight or more, the desired nap length can be obtained by grinding with sandpaper or the like. In addition, by making it less than 5% by weight, deterioration of light resistance can be prevented.

In addition, from the viewpoint of improving the durability of hydrolysis resistance and light resistance, it is preferable not to use polyether diols other than polycarbonate diols and polysiloxane polyols, polyether diols, poly Lipid diol.

Examples of organic diisocyanates used in the synthesis of polyurethane include 4,4'-diphenylmethane diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate, p-xylene diisocyanate, m-xylene Aromatic diisocyanates such as diisocyanate, alicyclic diisocyanates such as 4,4'-dicyclohexylmethane diisocyanate and isophorone diisocyanate, and aliphatic diisocyanates such as 1,6-hexamethylene diisocyanate. Among them, aromatic diisocyanates are preferably used, and 4,4'-diphenylmethane diisocyanate is particularly preferably used from the viewpoint of durability such as strength and heat resistance of the obtained polyurethane.

The ratio of the sum of polycarbonate diols (A) and (B) to the organic diisocyanate is preferably a molar ratio of both of them in the range of 1:2 to 1:5. In addition, within this range, when emphasis is placed on the flexibility of the obtained polyurethane, it can be adjusted by reducing the ratio of organic diisocyanate, and when strength, heat resistance, durability, etc. are emphasized, it can be adjusted by increasing the ratio of organic diisocyanate. The ratio of isocyanate to adjust.

In addition, when polysiloxane polyol (C) is further contained, the ratio of the sum of polycarbonate diols (A) and (B) and polysiloxane polyol (C) to organic diisocyanate is preferably The molar ratio of the two reaches 1:2～1:5. In addition, within this range, when emphasis is placed on the flexibility of the obtained polyurethane, it can be adjusted by reducing the ratio of organic diisocyanate, and when strength, heat resistance, durability, etc. are emphasized, it can be adjusted by increasing the ratio of organic diisocyanate. The ratio of isocyanate to adjust.

As the chain extender used in the synthesis of polyurethane, organic diols, organic diamines, hydrazine derivatives and the like can be used.

Examples of organic diols include ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, methylpentanediol, and 1,6-hexanediol , 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol and other aliphatic diols, 1,4-cyclohexanediol, hydrogenated xylene Alicyclic diols such as diols, and aromatic diols such as xylene glycol.

Examples of organic diamines include ethylenediamine, isophoronediamine, xylylenediamine, phenylenediamine, 4,4-diaminodiphenylmethane, and the like.

Hydrazine, adipic acid dihydrazide, isophthalic acid hydrazide, etc. are mentioned as an example of a hydrazine derivative.

When emphasis is placed on the hydrolysis resistance of polyurethane, organic diols are preferably used. Among them, aliphatic diols having 2 to 6 carbon atoms in the alkyl chain are preferred in terms of the strength, heat resistance, and yellowing resistance of polyurethane. , particularly preferably ethylene glycol. In addition, when emphasis is placed on the heat resistance of polyurethane, organic diamines are preferably used, and among them, aromatic diamines such as 4,4'-diaminodiphenylmethane, or aromatic diamines such as 4,4'- Diphenylmethane diisocyanate is converted to 4,4'-diaminodiphenylmethane by adding water.

In the synthesis of polyurethane, as a catalyst, for example, amines such as triethylamine and tetramethylbutylene diamine, metal compounds such as potassium acetate, zinc stearate, and tin octylate can be used.

The weight average molecular weight (Mw) of polyurethane is preferably 100,000 to 300,000, more preferably 150,000 to 250,000. By setting the weight average molecular weight (Mw) to 100,000 or more, the strength of the obtained sheet-like article can be maintained, and the generation of pilling and pilling of napping can be prevented. Moreover, by making it 300,000 or less, the viscosity increase of a polyurethane solution can be suppressed, and impregnation with respect to a nonwoven fabric becomes easy.

In addition, it is important for the polyurethane used as the main component of the elastic resin adhesive in the present invention to have a gel point of 2.5 ml or more and less than 6 ml. More preferably, it is the range of 3 ml or more and 5 ml or less. Said gelation point in the present invention, is while stirring the N, N '-dimethylformamide (hereinafter referred to as DMF) solution 100g that contains 1% by weight of polyurethane, distilled water is added dropwise in this solution on the one hand, at 25 The value of the amount of water added when the solidification of polyurethane starts to become slightly cloudy at a temperature of ±1°C. Therefore, DMF used in the measurement needs to use DMF with a water content of 0.03% or less. The above-mentioned measurement method is described on the premise that the DMF solution of polyurethane is transparent. However, if the DMF solution of polyurethane has been slightly cloudy in advance, the amount of water added when the solidification of polyurethane starts and the degree of cloudiness changes for the first time regarded as the gelation point. In addition, the gelation point of polyurethane present in the sheet can be measured by extracting polyurethane from the sheet using DMF and adjusting the polyurethane concentration to 1% by weight.

The gelation point indicates the water tolerance when the polyurethane is wet-coagulated using a DMF solution of polyurethane, and polyurethane with a low gelation point tends to have a fast coagulation rate, while polyurethane with a high gelation point tends to have a slow coagulation rate. Therefore, when the gelation point is less than 2.5 ml, when the polyurethane is wet-coagulated, the coagulation speed is too fast, and the foaming of the polyurethane existing in the inner space of the nonwoven fabric is large and rough, and some foaming failures occur. As a result, in the case of grinding the surface of the sheet with sandpaper, the length of surface napping was uneven, and the nap quality was very bad. In addition, since the polyurethane film becomes thinner, it is less effective as an adhesive for fixing fibers, and when brushing the surface with a brush or the like, there is a problem that many fibers fall off. On the other hand, when the gelation point is 6 ml or more, when the polyurethane is wet-coagulated, the coagulation rate is too slow, and the polyurethane existing in the inner space of the nonwoven fabric hardly sees foaming, and the film thickness is very large. Since there is thick and hard polyurethane, when the surface of the sheet is ground with sandpaper, it is difficult to grind the polyurethane, and the roughness on the surface is very short and poor in quality.

To make the gelation point of the polyurethane used in the present invention be 2.5 or more and less than 6 ml, although it also depends on the type of polysiloxane polyol (C), organic diisocyanate, and chain extender used for synthesizing polyurethane, amount, but it can be passed through the polycarbonate diol (A) having a hydroxyl group on the two ends of the molecular chain of the polycarbonate skeleton represented by the above general formula (1), and the polycarbonate diol (A) represented by the above general formula (2) Adjust the weight ratio of the polycarbonate diol (B) having hydroxyl groups at both ends of the molecular chain of the polycarbonate skeleton.

Within the range of gelation as the target, in order to suppress the gelation point low, it can be adjusted by increasing the ratio of polycarbonate diol (A), on the contrary, in order to increase the gelation point, it can be adjusted by reducing The ratio of carbonate diol (A) is adjusted.

In addition, the elastic resin adhesive uses polyurethane as the main component, but within the range that does not impair the performance and feel of the adhesive, it may contain elastic resins such as polyester, polyamide, and polyolefin. Body resin, acrylic resin, ethylene-vinyl acetate resin, etc., may also contain various additives, such as pigments such as carbon black, phosphorus-based, halogen-based, inorganic-based flame retardants, phenol-based, sulfur-based, phosphorus-based, etc. Antioxidant, benzotriazole-based, benzophenone-based, salicylate-based, cyanoacrylate-based, oxalanilide-based UV absorbers, hindered amine-based, benzoate-based, etc. Stabilizers, hydrolysis-resistant stabilizers such as polycarbodiimide, plasticizers, antistatic agents, surfactants, coagulation regulators, dyes, etc.

It has been described that the non-woven fabric used in the sheet of the present invention is preferably formed by intertwining fiber bundles of superfine fibers, but in this case, it is preferred that the elastic resin binder with polyurethane as the main component be used in superfine fibers. The inside of the fiber bundle of thin fibers does not exist substantially. If there is an elastic resin binder even inside the fiber bundle, it tends to be difficult to obtain a good hand feeling of the sheet obtained by the voids inside the fiber bundle, because it is bonded to the single fiber of the ultrafine fiber constituting the fiber bundle, Therefore, when roughening is performed with sandpaper or the like, it is easy to cause cutting of fibers, and there is a tendency to deteriorate the quality.

As a method of obtaining a form in which the elastic resin binder mainly composed of polyurethane exists in the internal space of the nonwoven fabric, but does not substantially exist in the fiber bundles of ultrafine fibers, the following method can be preferably used: After polyurethane is made into a solution with solvents such as dimethylformamide, dimethylacetamide, tetrahydrofuran, and dioxane,

(1) In the non-woven fabric obtained by intertwining the island-in-the-sea type composite fiber of the superfine fiber generation type, impregnate the solution of polyurethane, and after solidifying it in water or an aqueous organic solvent solution, the sea component of the island-in-sea type composite fiber The method of dissolving and removing with a solvent that does not dissolve polyurethane,

(2) Polyvinyl alcohol with a saponification rate of preferably 80% or more is given to the non-woven fabric obtained by entangling the island-in-the-sea composite fiber of the superfine fiber generation type to protect most of the surrounding fibers, and then the island-in-sea composite fiber is The sea component is dissolved and removed with a solvent that does not dissolve polyvinyl alcohol, and then impregnated with a polyurethane solution, solidified in water or an aqueous organic solvent solution, and then the polyvinyl alcohol is removed.

In addition, as the form in which the elastic resin binder exists inside the nonwoven fabric, in order to reduce fiber shedding and pilling and obtain a good hand feeling, it is preferable that at least a part of the single fiber located at the outermost periphery of the fiber bundle of the ultrafine fiber Bonded. This form can be obtained by the method of (2) above. That is, since polyvinyl alcohol protects most of the outer periphery of the microfiber bundle, polyurethane is prevented from penetrating into the fiber bundle, and polyurethane partially adheres to the outer periphery of the fiber bundle that is not protected by polyvinyl alcohol.

In the sheet-like article of the present invention, the proportion of the elastic resin binder in the sheet-like article is preferably 10 to 50% by weight, more preferably 15 to 35% by weight. When the ratio is 10% by weight or more, sheet strength can be obtained and fiber shedding can be prevented, and when the ratio is 50% by weight or less, the texture can be prevented from becoming hard, and the desired good nap quality can be obtained.

The sheet-like object of the present invention may be obtained by cutting or dividing the sheet into several pieces in the direction of the thickness of the sheet before the napping treatment.

In addition, it is preferable to apply an antistatic agent before napping because the grinding dust generated from the flakes by grinding tends to be difficult to accumulate on the sandpaper.

As described above, the sheet of the present invention can be finally used suitably as a napped leather-like sheet having microfibers napped on at least one side thereof.

The sheet, especially a napped leather-like sheet obtained by napping microfibers on at least one side of the sheet, is used as an interior decoration for furniture, chairs, wall decorations, and compartments of automobiles, trains, and airplanes. Surface materials for seats, ceilings, interiors, etc. can be suitably used as interior materials with a very elegant appearance.

Example

Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited only to the following Example.

[Evaluation method]

(1) Gelation point of polyurethane

While stirring 100 g of a DMF solution of 1% by weight polyurethane, distilled water was added dropwise to the solution, and at a temperature of 25±1° C., the value of the amount of water added when solidification of the polyurethane started and slightly clouded was measured. In addition, the DMF used for the measurement used the DMF whose water|moisture content was 0.03 % or less. When the DMF solution of polyurethane has been slightly cloudy in advance, the amount of water added when the solidification of polyurethane starts and the degree of cloudiness changes for the first time is taken as the gelation point.

(2) Appearance grade

The surface quality of the obtained napped leather-like sheet was evaluated by visual sensory evaluation as follows.

⊚: Both the nap length and the dispersed state of fibers are very good.

◯: Both the nap length and the dispersed state of fibers are good.

X: The nap length is good, but the dispersion of fibers is poor.

××: The nap length is short and defective.

×××: There is almost no picking, which is a remarkable defect.

(3) Fineness CV

Using a scanning electron microscope (SEM) to observe the cross-section in the thickness direction of the sheet, measure the fiber diameter of the ultrafine fibers inside a bundle of fibers constituting the bundle from the photo, and convert the fiber diameter into the fineness of each single fiber to form a The value obtained by dividing the standard deviation of the fineness of the fibers of the fiber bundle by the average fineness in the bundle is expressed in percentage (%). The same measurement was performed for five bundled fibers, and the average value was taken as the fineness CV.

(4) Brush wear reduction

Arrange 100 nylon filaments with a length of 11mm and a diameter of 0.4mm into bundles, arrange 97 of these bundles in 6 concentric circles in a circle with a diameter of 110mm, and use the thus obtained circular brush (9700 nylon filaments), Under the conditions of a load of 8 pounds (about 3629g), a rotating speed of 65rpm, and a rotation speed of 45 revolutions, the surface of the round sample (diameter 45mm) of the brushed imitation leather sheet is worn, and the weight change of the sample before and after wearing Acts as a brush wear reducer.

(5) Durability - hydrolysis resistance

The obtained brushed leather-like sheet was placed in a constant temperature and humidity chamber manufactured by Dabi Espec Co., Ltd., and placed in an atmosphere with a temperature of 70° C. and a relative humidity of 95% for 10 weeks to implement forced aging treatment, and then used James H. Model 406 manufactured by Heal & Co. was used as a Martindel abrasion tester, ABRASTIVE CLOTH SM25 manufactured by the company was used as a standard friction cloth, a load equivalent to 12kPa was applied, and the friction was observed visually after friction at 20,000 revolutions. Appearance of the samples and evaluate. The evaluation criteria were that the appearance of the sample remained unchanged from that before rubbing and rated as 5, and the case where many pompons occurred was rated as 1, and the points between 5 and 1 were divided by 0.5. In addition, the passing level in the present invention is defined as level 4.

(6) Durability - light resistance

The obtained brushed leather-like sheet was subjected to a forced aging treatment by irradiating light with a wavelength of 300 to 400 nm for 144 hours using a xenon lamp weather resistance tester manufactured by Suga Test Equipment Co., Ltd. using a 150 W/m ² xenon lamp. Model 406 manufactured by Heal & Co. was used as a Martindel abrasion tester, ABRASTIVE CLOTH SM25 manufactured by the company was used as a standard friction cloth, a load equivalent to 12kPa was applied, and the friction was visually observed under the condition of 20,000 rotations of friction After the appearance of the sample, and evaluate. The evaluation criteria were that the appearance of the sample remained unchanged from that before rubbing and rated as 5, and the case where many pompons occurred was rated as 1, and the points between 5 and 1 were divided by 0.5. In addition, the passing level in the present invention is defined as level 4.

(7) Processability evaluation

As described in Example 1 (manufacture of sheet-like article) described later, when the sheet-like article is napped using ring-shaped sandpaper, even if the processing is continuous for 3,000 m or more, the evaluation that there is little clogging of the sandpaper is described as " "Good", before 3,000 m, the clogging of the sandpaper was remarkable, and the evaluation of processing was interrupted, and it was recorded as "Poor".

[Notation of Chemical Substances]

The meanings of the abbreviations of the chemical substances used in Examples and Comparative Examples are as follows.

PU: Polyurethane

MDI: 4,4'-Diphenylmethane diisocyanate

EG: ethylene glycol

DMF: N,N-Dimethylformamide

PNMOC: Copolycarbonate diol derived from 1,9-nonanediol and 2-methyl-1,8-octanediol with a number average molecular weight of 2,000 represented by the following general formula (4)

(In the formula, n and m are positive integers and are random copolymers. In addition, R represents any aliphatic hydrocarbon group in (CH ₂ ) ₉ or CH ₂ -CH(CH ₃ )-(CH ₂ ) _6. )

PHC: polyhexamethylene carbonate diol with a number average molecular weight of 2,000

PHMPC: Copolycarbonate diol derived from 1,6-hexanediol and 3-methyl-1,5-pentanediol with a number average molecular weight of 2,000 represented by the following general formula (5)

(In the formula, x and y are positive integers and are random copolymers. In addition, R represents any aliphatic hydrocarbon group in (CH ₂ ) ₆ or CH ₂ -CH(CH ₃ )-(CH ₂ ) _2. )

PTMG: Polytetramethylene glycol with a number average molecular weight of 2,000

PCL: polycaprolactone diol with a number average molecular weight of 2,000

KSi-1000: Polysiloxane polyol having 2 hydroxyl groups at one end of polydimethylsiloxane having a number average molecular weight of 1,000 represented by the following general formula (6)

KSi-1500: Polysiloxane polyol having 2 hydroxyl groups at one end of polydimethylsiloxane having a number average molecular weight of 15,000 represented by the following general formula (6)

(where p is a positive integer)

BSi-1800: a polysiloxane polyol having a number average molecular weight of 18,00 and one hydroxyl group at each end of polydimethylsiloxane represented by the following general formula (7)

(where p is a positive integer)

Example 1

(Manufacture of nonwoven fabric)

Polystyrene was used as the sea component, polyethylene terephthalate was used as the island component, and an island-in-the-sea composite spinneret with 16 islands was used. The composite ratio is spun to form sea-island composite fibers, then stretched, crimped, and cut to obtain raw cotton for non-woven fabrics.

The obtained raw cotton is formed into a web using a cross-lapping machine, and is formed into a non-woven fabric through needle punching.

The nonwoven fabric made of this sea-island composite fiber was dipped in a 10% polyvinyl alcohol aqueous solution having a degree of saponification of 87%, and then dried. Then, polystyrene as a sea component was extracted and removed in trichloroethylene, and dried to obtain a nonwoven fabric composed of ultrafine fibers with a single fiber fineness of 0.1 dtex.

(manufacture of polyurethane)

60 parts by weight of PNMOC and 40 parts by weight of PHMPC as polyol, MDI as organic diisocyanate are packed into a four-necked detachable flask with a cooling tube, DMF is used as solvent, and the total amount of polyol: MDI The molar ratio is 1:3, and the stirring reaction is carried out at 40-60°C under a nitrogen atmosphere, and EG is added dropwise as a chain extender at 50-60°C in a state diluted with DMF. After the reaction, it was gradually diluted with DMF, and after about 10 hours, a PU solution with a solid content of 25% was obtained. The gelation point of the obtained polyurethane was 3.5 ml.

(manufacture of sheet)

The above-mentioned non-woven fabric made of microfibers is immersed in a solution in which the concentration of the above-mentioned polyurethane DMF solution is adjusted to 12%, and after adjusting the adhesion amount of the PU solution with a nip roll, the DMF concentration at 30°C is 30%. The PU is solidified in the aqueous solution. Then, polyvinyl alcohol and DMF were removed with hot water at 90°C, dried, and then immersed in a mixed aqueous solution of a polysiloxane emulsion solution and a nonionic antistatic agent (Elenite 139, manufactured by Takamatsu Yushi Co., Ltd.) and dried. , A sheet-like product having a PU content of 32% by weight, a polysiloxane content of 0.2%, and an antistatic agent content of 0.1% by weight was obtained. One side of the sheet was napped using 150 mesh and then 240 mesh annular sandpaper, and dyed with disperse dyes to obtain a napped leather-like sheet.

Observation of the cross-section in the thickness direction of the obtained imitation leather sheet with a scanning electron microscope (SEM) confirmed that polyurethane does not substantially exist in the inside of the ultrafine fiber bundle, but is combined with the unit located at the outermost periphery of the ultrafine fiber bundle. The fibers are partially bonded. In addition, the fineness CV was 7.5%.

The obtained napped leather-like sheet had good nap length and dispersibility of fibers, and had a beautiful appearance. In addition, it has a good texture with moderate resilience and a feeling of fullness. The reduction in brush abrasion was as small as 15 mg, and the evaluation results of hydrolysis resistance and light resistance, which are durability evaluations, were all 4.5 grades, showing excellent durability.

Embodiment 2～4, comparative example 1～5

Production of polyurethane was carried out in the same manner as in Example 1, except that the composition and weight ratio of the polyols were changed to those shown in Table 1, respectively, and a napped leather-like sheet was produced.

Observation of the cross section in the thickness direction of the inside of the imitation leather sheet in Examples and Comparative Examples with a scanning electron microscope (SEM), as a result, polyurethane does not exist in the inside of the microfiber bundle substantially, but is located in the superfine fiber bundle. The outermost single fibers are partially bonded. Table 1 shows the composition and gelation point of the polyurethane in each example and comparative example, and the appearance quality, brush wear reduction, and durability of the obtained sheet.

Table 1

Any of the brushed leather-like sheets of Examples 1 to 4 had a beautiful appearance quality, and were also excellent in brush wear reduction and durability. The sheet-like objects of Comparative Examples 1, 2, and 3 were poor in appearance quality, and the sheet-like objects of Comparative Examples 4 and 5 were inferior in brush wear reduction and durability.

In addition, in any of Examples 1-4 and Comparative Examples 1-5, in terms of workability, clogging by sandpaper during buffing was remarkable before the work length was 3,000 m, and the workability was "poor".

Example 5

(Manufacture of nonwoven fabric)

Polystyrene was used as the sea component, polyethylene terephthalate was used as the island component, and an island-in-the-sea composite spinneret with 16 islands was used, with 55% by weight of the sea component and 45% by weight of the island component. The composite ratio is spun to form sea-island composite fibers, then stretched, crimped, and cut to obtain raw cotton for non-woven fabrics.

The obtained raw cotton is formed into a web using a cross-lapping machine, and is formed into a non-woven fabric through needle punching.

The nonwoven fabric made of this sea-island composite fiber was dipped in a 10% polyvinyl alcohol aqueous solution having a degree of saponification of 87%, and then dried. Then, polystyrene as a sea component was extracted and removed in trichlorethylene, and dried to obtain a nonwoven fabric in which fiber bundles composed of ultrafine fibers with a single fiber fineness of 0.1 dtex were entangled.

(manufacture of polyurethane)

60 parts by weight of PNMOC as polycarbonate diol (A), 40 parts by weight of PHMPC as polycarbonate diol (B), 2 parts by weight of KSi-15000 as polysiloxane polyol (C), as The MDI of organic diisocyanate is put into a four-necked detachable flask with a cooling tube, DMF is used as a solvent, and the molar ratio of the total polyol {(A)+(B)+(C)}:MDI is 1:3, stirring reaction at 40-60°C under a nitrogen atmosphere, and further dropwise adding EG as a chain extender at 50-60°C in a state diluted with DMF for dropwise reaction, It was slowly diluted with DMF, and after about 10 hours, a PU solution with a solid content of 25% was obtained. The gelation point of the obtained polyurethane was 3.5 ml.

(manufacture of sheet)

The above-mentioned non-woven fabric made of microfibers is immersed in a solution in which the concentration of the above-mentioned polyurethane DMF solution is adjusted to 12%, and after adjusting the adhesion amount of the PU solution with a nip roll, the DMF concentration at 30°C is 30%. The PU is solidified in the aqueous solution. Then, polyvinyl alcohol and DMF were removed with hot water at 90° C., dried, and then immersed in an aqueous solution of a nonionic antistatic agent (Elenite 139, manufactured by Takamatsu Yushi Co., Ltd.), and dried to obtain a PU content of 32 wt. %, antistatic agent content of 0.1% by weight of flakes. One side of the sheet was ground first with 150-mesh and then 240-mesh annular sandpaper, thereby napping, and dyed with a disperse dye to obtain a napped leather-like sheet.

Observation of the cross-section in the thickness direction of the obtained imitation leather sheet with a scanning electron microscope (SEM) confirmed that polyurethane does not substantially exist in the inside of the ultrafine fiber bundle, but is combined with the unit located at the outermost periphery of the ultrafine fiber bundle. The fibers are partially bonded. In addition, the fineness CV was 7.3%.

The obtained napped leather-like sheet had good nap length and dispersibility of fibers, and had a beautiful appearance. In addition, it has a good texture with moderate resilience and a feeling of fullness. The reduction in brush wear was as small as 12 mg, and the evaluation results of hydrolysis resistance and light resistance, which were durability evaluations, were all 4.5 grades, showing excellent durability. Furthermore, in the napping process, even after the sheet-shaped object was continuously processed for 3,000 m, there was little clogging of the sandpaper, and the workability was "good".

Embodiment 6-11

Production of polyurethane was carried out in the same manner as in Example 5 except that the polyol composition, weight ratio, and gelation point were changed to those shown in Table 2, and a napped leather-like sheet was produced.

In the processability in each example, even after continuous processing of a sheet-shaped object for 3,000 m, there was little clogging with sandpaper, and the processability was "good".

Table 2 shows the composition of the polyurethane in each example, the appearance quality of the obtained sheet, the brush wear reduction, and the durability performance.

Table 2

In the production of polyurethane, a polysiloxane polyol having two hydroxyl groups at one end of polydimethylsiloxane was used, and a polyurethane having a polyorganosiloxane skeleton in the side chain was applied. The brushed leather-like sheet of any one of 5 to 9 has a beautiful appearance quality and is excellent in both brush wear reduction and durability even if it is not dipped in a silicone emulsion before the brushing treatment with sandpaper. In particular, a sheet obtained by using polysiloxane polyol (KSi-15000) having a number average molecular weight of 15,000 is excellent in appearance quality even if it is used in a small amount. On the other hand, Example 10 using polysiloxane polyol (BSi-1800) having 1 hydroxyl group at both ends of polydimethylsiloxane is different from that using polydimethylsiloxane Compared with Example 5 and Example 9, the polysiloxane polyol having two hydroxyl groups at one end of the oxane has a poor appearance quality, and one polydimethylsiloxane is used at each end of the polydimethylsiloxane. Hydroxyl polysiloxane polyol (BSi-1800) to obtain a good appearance grade, the composition of the polyol needs to be 10 parts by weight, but if the content is more than 10 parts by weight, the light resistance will be poor.

Industrial availability

According to the present invention, it is possible to provide a napped leather-like sheet which has a beautiful appearance due to napping and is also excellent in durability such as hydrolysis resistance and light resistance. As a result, it is possible to obtain the advantage that there is little time-varying change in the quality of napping such as terry cloth even if it is used for many years, and it can be used as furniture, chairs, wall decorations, and seats, ceilings, Surface materials such as interiors can be suitably used as interior materials having a very elegant appearance.

Claims (17)

1. flap, be to be the non-woven fabrics that forms of the ultra-fine fibre complexing below the 0.5dtex and to be that the elastic resin tackiness agent of principal constituent forms with urethane by the ultimate fibre fiber number, in this flap, described urethane is the polycarbonate-based urethane with the polycarbonate skeleton shown in following general formula (1) and (2), the weight-average molecular weight of urethane is 100,000～300,000, gelation point is more than the 2.5ml, less than 6ml

In the formula, R ₁And R ₂Be that carbonatoms is 7～11 aliphatic alkyl, identical or different, in addition, n and m are positive integer, at R ₁And R ₂Under the different situations, be block copolymerization or random copolymerization;

In the formula, R ₃And R ₄Be that carbonatoms is 3～6 aliphatic alkyl, identical or different, in addition, x and y are positive integer, at R ₃And R ₄Under the different situations, be block copolymerization or random copolymerization.

2. flap as claimed in claim 1, described urethane are the urethane that further has the side chain that contains the organopolysiloxane skeleton shown in the following general formula (3),

In the formula, R ₅And R ₆Be aliphatic alkyl or aryl, identical or different, in addition, p is 100～300.

3. flap as claimed in claim 1, described gelation point are 3～5ml.

4. flap as claimed in claim 1, described urethane is that the reaction by following substances obtains, and described material is: at the polycarbonate diol (A) that hydroxyl is arranged on two ends of the molecular chain with the polycarbonate skeleton shown in the above-mentioned general formula (1), have polycarbonate diol (B), organic diisocyanate and chain propagation agent that hydroxyl is arranged on two ends of molecular chain of the polycarbonate skeleton shown in the above-mentioned general formula (2).

5. flap as claimed in claim 2, described urethane is that the reaction by following substances obtains, and described material is: the polycarbonate diol (A) that hydroxyl is arranged on two ends of the molecular chain with the polycarbonate skeleton shown in the above-mentioned general formula (1), the polycarbonate diol (B) that hydroxyl is arranged on two ends of the molecular chain with the polycarbonate skeleton shown in the above-mentioned general formula (2), the polysiloxane polyhydric alcohol (C) that two hydroxyls are only arranged on an end of the molecular chain with the organopolysiloxane skeleton shown in the above-mentioned general formula (3), organic diisocyanate and chain propagation agent.

6. flap as claimed in claim 5, the number-average molecular weight of described polysiloxane polyhydric alcohol (C) surpass 10,000 but be below 20,000.

7. flap as claimed in claim 5, above-mentioned polysiloxane polyhydric alcohol (C) is more than the 0.1 weight %, less than 5 weight % with respect to the ratio of the summation of above-mentioned polycarbonate diol (A) and above-mentioned polycarbonate diol (B).

8. flap as claimed in claim 1, the R that in the formula shown in above-mentioned general formula (1) and (2), puts down in writing ₁, R ₂, R ₃, R ₄Be whole different aliphatic alkyls to each other.

9. flap as claimed in claim 1, the R that in the formula shown in the above-mentioned general formula (1), puts down in writing ₁And R ₂At least one side, be by methyl or ethyl branching aliphatic alkyl.

10. flap as claimed in claim 1, the R that in the formula shown in the above-mentioned general formula (2), puts down in writing ₃And R ₄At least one side, be by methyl or ethyl branching aliphatic alkyl.

Form 11. flap as claimed in claim 1, described non-woven fabrics are the fibrous bundle complexings by ultra-fine fibre, described elastic resin tackiness agent does not exist in fact in the inside of the fibrous bundle of this ultra-fine fibre.

12. flap as claimed in claim 11, described elastic resin tackiness agent is bonding with filamentary at least a portion of the most peripheral of the fibrous bundle that is positioned at this ultra-fine fibre.

13. the filamentary fiber number CV in the flap as claimed in claim 1, the fibrous bundle of this ultra-fine fibre is below 10%.

14. flap as claimed in claim 1, described ultra-fine fibre comprises polyester.

15. flap as claimed in claim 1, above-mentioned elastic resin tackiness agent shared ratio in flap is more than the 10 weight %, below 50% weight.

16. flap as claimed in claim 1, this ultra-fine fibre is in the plucking attitude on the one side at least of flap.

17. an inner decoration material uses each described flap of claim 1～16 and constitutes.