JPS61146879A - Leathery sheetlike material and production thereof - Google Patents

Abstract

PURPOSE:A flexible leathery sheet, consisting of the upper layer consisting of a specific polyurethane layer and the lower layer consisting of ultrafine polyamide fibers entangled at a given distance between fiber entangling points and a specific crosslinking resin, and having improved color fastness and durability. CONSTITUTION:A sheet, consisting of the lower layer (II) obtained by jetting a high-speed fluid on the surface of a nonwoven fabric prepared by needle punching polyamide based fibers capable of forming ultrafine fibers, e.g. 0.002 denier, applying a crosslinking polyurethane resin to the surface, on which the above-mentioned fluid is jetted, of the resultant fiber structure containing densely entangled ultrafine fibers at <=200mu distance between fiber entangling points and/or bundles thereof, and bonding and combining the entangled fibers with the crosslinking polyurethane resin under heating and the upper layer (I) obtained by applying a polyurethane containing >=70% polyoxyethylene glycol component in soft segments to the surface, to which the above-mentioned polyurethane is applied, to give 0.2-3mu average thickness.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a material that is flexible in texture and touch, has excellent durability,
It has a deep and clear color tone, and has good color fastness.
In particular, it relates to a leather-like sheet material that is charge sorb resistant and has excellent dry cleaning properties using synthetic solvents.

[Prior Art] Conventionally, leather-like sheet materials having a grain layer have been produced by applying a urethane polymer or the like on a porous sheet obtained by adding an elastic polymer to a fiber aggregate such as a nonwoven fabric or a knitted or woven fabric. The grain layer is formed by laminating and integrating a thick porous or non-porous layer made of resin, or a non-porous layer and a porous layer. However, such leather-like sheets lack a sense of unity, have a strong rubber-like rebound feeling due to the elasticity of the urethane polymer, and have the disadvantages of being easily scratched. Furthermore, the resin used to form such a silver surface layer generally has poor affinity for dyes, and sufficient fastness cannot be obtained even when colored by dyeing, so a coloring method is used in which pigments are pre-dispersed and mixed into the resin. Therefore, such a leather-like sheet material has a uniform surface gloss, a strong sense of opacity, and a deep and clear color tone cannot be obtained. In order to improve these defects, a dye-containing resin layer is added to the outermost layer, or an easily dyed polyurethane is added to the silver surface layer.
Polyurethane whose soft segment is composed of polyoxyethylene glycol (hereinafter referred to as PEG-based polyurethane)
A method of dyeing with metal complex dye using
No. 8041) and the like have been proposed. However, in this method, the base sheet is impregnated or coated with a porous binder, so even if easily dyed PEG-based polyurethane is used for the surface layer, the color tone of the porous layer may not be visible through the surface layer. Since the porous binder had insufficient fastness, the color fastness of the sheet as a whole was low. In addition, in these methods, since the urethane polymer has a porous structure in the grain layer or directly under the grain layer, it is impossible to avoid a strong rubbery feel and touch due to the elastic properties of the urethane polymer. Ta.

On the other hand, in order to improve the texture and touch of the grain layer, it is possible to combine a planar array of fine fiber bundles with a porous layer, or to create fine fiber fluff on the substrate surface and integrate the fluff fibers and resin. Many proposals have been made, such as a method of forming a grain layer by oxidation, but in such methods, if the fiber bundle is rubbed strongly or shear stress is repeatedly applied, peeling may occur along the arrangement plane of the fiber bundles. The problem was that the surface became fluffy. In recent years, in order to solve this problem, a method has been proposed in Japanese Patent Application Laid-Open No. 2003-11111 in which ultrafine fibers and/or bundles thereof are densely entangled using a high-speed fluid flow, and a grain layer is formed by compositely integrating the entangled fibers and a resin. This is proposed in Japanese Patent No. 58-191280.

This method has made it possible to obtain a texture, grain touch, durability, etc. that is significantly improved compared to conventional methods; however, the grain layer uses a common resin;
and ultra-fine fibers, both of which resulted in poor fastness and still had the serious drawback that the colored hue would completely fade if dry cleaned.

Therefore, a leather-like sheet material that is flexible in texture and touch, has excellent durability, has a deep and clear color tone, and has excellent color fastness has not yet been found.

[Problems to be Solved by the Invention] The purpose of the present invention is to provide leather that has a supple feel and soft texture, is colored in a deep and clear tone, and has excellent durability and color fastness. The purpose of this invention is to provide a similar sheet-like product.

[Means for Solving the Problems] The leather-like sheet material of the present invention has a grain layer mainly composed of polyurethane containing 70% or more of a polyoxyethylene glycol (hereinafter simply referred to as PEG) component in the soft segment. an upper layer (1) containing polyamide ultrafine fibers substantially adhered by crosslinked polyurethane and/or a dense fiber entangled body in which the distance between fiber entanglement end points of a bundle thereof is 200 microns or less, and the crosslinked polyurethane. The sheet material is basically formed from a lower layer (II) mainly consisting of . It is this combination that gives the silver surface a natural feel without any artificial appearance.
It has now become possible to provide a leather-like sheet material that has a deep color tone, is supple in texture and touch, and has excellent durability and color fastness.

The polyamide ultrafine fibers used in the present invention may be produced by direct spinning methods such as super draw or melt blowing, and are made into ultrafine fibers at an appropriate stage during the process using the ultrafine fiber forming type fibers described in the grammar. Although it may be modified into fibers, the latter is preferred from the viewpoint of ease of processing and handling.

Examples of the microfiber-forming fibers include fibers with a chrysanthemum-shaped cross section, multilayer bimetallic fibers, multilayer bimetallic fibers with a donut-shaped cross-section, mixed spun fibers, and polymer interlayer fibers. Furthermore, two or more types of these fibers may be used as a mixture or in combination.

In the present invention, a polyamide-based polymer having fiber-forming ability is used as an ultrafine fiber component, and such polyamides include, for example, nylon-6, nylon-66, nylon-12, nylon-610, copolymerized nylon, etc.
Examples include ACM-12. Among them, nylon-6
, nylon-66 are preferred.

Alternatively, a modified polyamide obtained by blending or copolymerizing PEG with such polyamide may be used.

In addition, when ultrafine fiber-forming fibers are used, the binding component of the fibers or the dissolving and removing component may be, for example, polystyrene, polyethylene, styrene-acrylonitrile copolymer, higher alcohol ester of styrene and acrylic acid, and/or methacrylic acid. Examples include copolymers with higher alcohol esters. Polystyrene, styrene-acrylonitrile copolymers, and copolymers of styrene and higher alcohol esters of acrylic acid and/or higher alcohol esters of methacrylic acid are preferred in terms of ease of spinning and ease of dissolution and removal. Furthermore, a copolymer of threadin and a higher alcohol ester of acrylic acid and/or a higher alcohol ester of methacrylic acid is particularly preferable since a high stretching ratio can be obtained and a fiber with high strength can be obtained.

The fineness of the ultrafine fibers in the lower grain layer of the present invention is preferably 0.2 denier or less in order to obtain a supple feel, soft texture, and elegant luster.

0.05 denier or less In particular, in the case of 0.01 denier or less, as mentioned above, a dense intertwined structure of ultrafine fibers can be easily obtained, and a fibrous sheet with a more delicate touch and texture can be obtained. Therefore, it is particularly preferable.

Further, the fiber structure in the lower grain layer of the leather-like sheet product of the present invention requires that ultrafine fibers and/or bundles thereof are closely intertwined with each other (high intertwining density). One method for measuring the entanglement density of such fibers is the method of measuring the distance between fiber entanglement points described in JP-A-58-191280. It is necessary to have a value of 200 microns or less and to be densely intertwined.

If the structure has a value larger than 200μ, for example, if the fibers are entangled with each other only by needle punching, and the fiber structure is less entangled, the surface may become fluffy or crack when subjected to abrasion, kneading, or repeated shearing force. This is not desirable because it is likely to occur. Such a base sheet must be reinforced with a large amount of porous resin in order to maintain its shape, and as a result, due to the poor fastness of the porous resin, the sheet as a whole has poor color fastness. It couldn't happen. In order to eliminate these drawbacks, the distance between fiber entanglement points must be 200μ or less, and 100μ
More favorable results can be obtained in the following cases.

Based on the distance between fiber entanglement points, the fiber structure is mainly made of a densely entangled fiber structure of 200μ or less, and a crosslinked polyurethane described below that has a substantial adhesion ability to the polyamide fibers forming the fiber structure. A leather-like sheet material having a grain layer formed of a composite layer as a lower layer and a layer mainly composed of polyurethane containing 70% or more of a polyoxyethylene glycol component in the soft segment as an upper layer, The object of the present invention can be achieved by the dyeing/fixing method described below.

Therefore, there is no particular limitation on the lower layer structure below the grain layer. It may be a single nonwoven structure, or it may be a nonwoven fabric with a knitted fabric inserted inside the nonwoven fabric to form an inseparable and integrated structure.

By the way, the base sheet is made of ultrafine fibers and/or bundles thereof that are densely intertwined, and the fibers are substantially continuous between the grain layer and the lower layer below the grain surface, and the fibers are intertwined near the grain surface. If the fiber structure has a strong degree of branching and the degree of branching changes continuously at the boundary between the two layers, a texture with a sense of unity will be obtained, and the grain layer and the lower layer will peel off. This is preferable because there are no problems. Note that entanglement and branching can also be applied to the entire thickness direction of the sheet. Moreover, if the fiber structure is made up of fine fibers and/or bundles thereof, the sheet will not stretch abnormally even if the amount of resin in the lower layer is small or even if it is not applied, and the sheet will maintain its shape well. be. The amount of resin applied varies depending on the intended use of the sheet, but when used for clothing, it is preferably applied in an amount of 0 to 50% based on the weight of the fibers, and particularly preferably 20% or less.

Now, in order to obtain a grain surface appearance with high fastness and a deep and clear color tone, which is the objective of the present invention, the polyurethane mainly used for the upper layer of the grain surface contains 70% PEG component as the soft segment component. It is necessary to contain the above amount. If the PEG component is less than 70%, the desired high fastness cannot be achieved. The higher the proportion of PEG in the soft segment components, the better the color fastness of the polyurethane, and it is most preferable that the entire soft segment of the polyurethane is composed of PEG alone. P of the upper layer of the grain layer
The deep and vivid color tone of the present invention is achieved by the combination of the hues of the EG polyurethane and the finely entangled ultrafine fibers constituting the lower layer. However, the dye affinity of such PEG-based polyurethane is greater than that of ultrafine fibers, and it has the disadvantage that color unevenness tends to occur due to the difference in hue between the two (especially reddish colors), but the present invention By using the silver surface structure, the PEG content contained in the upper layer resin can be easily adjusted by changing the polymerization conditions such as the resin layer thickness, the soft segment molecular weight of the resin, and the soft segment/hard segment ratio. can be controlled to adjust the hue balance between the fiber and the resin. In the conventional grain layer consisting only of a resin layer, if the thickness of the resin layer is made extremely thin, there are serious problems such as poor abrasion resistance, bending fatigue resistance, etc., and color unevenness due to the base sheet. However, as in the present invention, the thickness of the upper layer can be reduced to 3μ or less, especially 1μ by making the lower grain layer a composite integrated structure of densely entangled ultrafine fibers and crosslinked polyurethane.
Even if it is an ultra-thin layer, there is no problem of deterioration of abrasion resistance etc., and the hue can be freely controlled to adjust the hue with the ultra-fine fibers.

By the way, the cross-linked polyurethane used for the grain-faced lower layer is required to have the ability to adhere to the ultrafine fibers and/or bundles thereof substantially constituting the lower layer. Here, "substantially having adhesive ability" means having a peel strength of at least 0.5 kq/cm when the peel strength is measured by the method shown below. As for such adhesion ability, a peel strength of 1°0 kg/cm or more is preferable.

The adhesion ability between the ultrafine fibers and the polyurethane is determined by molding a film using polyamide, which is the raw material forming the fibers, and coating the film with a 25% solution of the crosslinked polyurethane to a thickness of 150 mm. ~200μ
After creating a dry film, as shown in the figure, the peeling strength is measured when it is peeled from the interface between the polyamide film and polyurethane film over a length of 1 QCm per unit width. With this method, the peel strength can be reduced to 0.5 kg/
A urethane with a molecular weight of Cm or more is required.

Such polyurethane may be a substantially linear type polyurethane crosslinked using a crosslinking agent, or a urethane polyol having a reactive group such as a hydroxyl group at the end of the molecule or in the molecule and a crosslinking agent, if necessary. A two-component polyurethane that is crosslinked by adding a catalyst may also be used. Although there is no particular limitation on the soft segment of such crosslinked polyurethane, it is preferable to use one containing PEG also in the soft segment portion, since this further improves the robustness. In particular, it is more preferable that the soft segment is also composed of PEG alone. However, the crosslinked polyurethane is PE.
When containing G, the dyeing balance can be controlled by lowering the soft segment molecular weight and/or lowering the soft segment/hard segment ratio in the PEG-based polyurethane used for the upper grain layer;
It is preferable to reduce the content of PEG in all the constituent components of the polymer and use a hard type PEG-based polyurethane having a content of 140% or less.

If the content is 35% or less, especially 30% or less, no matter what amount of PEG the crosslinked polyurethane of the lower layer contains as a soft segment component, it is especially suitable because the hue with the fibers is moderately harmonized. preferable.

Further, the PEG-based polyurethane of the upper grain surface layer used in the present invention is not limited to a substantially linear type polyurethane, but may be cross-linked as necessary using a cross-linking agent such as a trimer of hexamethylene diisocyanate. , crosslinked type polyurethane. In general, it has been said that cross-linked polyurethane or hard type polyurethane with high modulus for the grain layer has good scratch resistance, but poor bending fatigue resistance.However, in the present invention, the structure of the lower grain layer is Since it is a composite of an entangled body and a crosslinked polyurethane, there is no problem in bending fatigue resistance, and it is also effective in improving solvent resistance, hot water resistance, etc., which is preferable.

As the soft segment of the PEG-based polyurethane used in the upper grain layer of the present invention, in addition to PEG, other polyether diols, polyester diols, etc. may be used as a blend or copolymer within a range not exceeding 30%.

If components other than PEG are contained beyond this point, the fastness (particularly against discoloration and fading) will be sharply reduced. When synthesizing such a PEG-based polyurethane, organic diisocyanates that are used in general polyurethane synthesis, such as aromatic, araliphatic, aliphatic, or alicyclic diincyanates, can be used, among which isophorone diisocyanate is used. Alicyclic types such as these are particularly preferred because they yield non-yellowing PEG-based polyurethanes. Furthermore, low molecular weight diols, aliphatic diamines, aromatic diamines, alicyclic diamines, alkanolamines, hydrazines, etc., which are generally used as chain extenders, may be used alone or in combination.

Now, the deep gloss, clear, and highly durable colored tone of the present invention is due to the combination of the PEG-based polyurethane used in the leather-like sheet material, especially the upper layer of the silver surface, and the lower layer. This is achieved by simultaneously coloring the densely entangled ultrafine fibers constituting the ultrafine fibers with a neutral metal-containing dye, which will be described later, and then fixing the ultrafine fibers with tannins and metal salts.

In the production of the base sheet of the present invention, first, sea-island fibers, which are typical microfiber-forming fibers, are produced using a spinning device such as that disclosed in Japanese Patent Publication No. 44-18369, and then processed into short fibers. After forming the web, the web is needle punched. Alternatively, the ultrafine fiber-forming fibers are formed into a web as long fibers, and needle punching is performed in the same manner as described above. Alternatively, the ultrafine fiber-forming fibers may be placed on a nonwoven fabric, woven fabric, or knitted fabric made of ordinary fibers or other ultrafine fiber-forming fibers, and then entwined and inseparably integrated to form a fiber sheet. Next, the fiber sheet thus obtained is brought into contact with a high-speed fluid stream to branch and densely intertwine at least one side of the fiber sheet into ultrafine fibers and/or bundles thereof, if necessary. Water is most preferably used as the fluid here. The fluid is brought into contact with the fiber sheet in a high-velocity columnar flow to effect branching and/or entanglement of the fibers. Thereafter, the ultrafine fibers can be further strengthened by applying a physical action to the ultrafine fiber-forming fibers or by treating the obtained fiber sheet with a solvent that dissolves at least some of the components. Note that the order of these operations may be reversed, in which case a high degree of branching and entanglement can be easily achieved with low fluid pressure. Alternatively, high-speed fluid flow treatment may be performed before and after the step of dissolving and removing the partial components.

Further, when applying a binder, the order thereof can be arbitrarily combined with respect to the high-speed fluid flow treatment step and the dissolution and removal step of some components of the fibers.

When applying a binder before the step of dissolving and removing the partial component, it is necessary that the applied resin does not dissolve in the solvent used to dissolve and remove the partial component, but the resulting fiber sheet This is a preferable method for making the texture soft because a space is created between the ultrafine fiber bundle and the resin where the part of the component existed, increasing the degree of freedom in mutual movement.

Next, cross-linked polyurethane for the lower grain layer of the present invention is applied by reverse roll coating, gravure coating, knife coating, slit coating, spraying, etc., but here, before applying the resin, the fiber sheet is It is also a preferable method to smoothen the surface by performing a treatment such as pressing.

Thereafter, PEG-based polyurethane is applied as an upper layer on the grain surface. Next, a heated embossing roll having a leather-like grain pattern is used to impart a grain pattern to form a grain surface. Before such graining, heat treatment may be performed to promote adhesion between the fibers and crosslinked polyurethane.

Further, the component dissolution and removal for ultra-fine formation can also be carried out after the formation of such a grain layer, and this is particularly preferred since a softer texture can be obtained.

The leather-like sheet thus obtained has a molecular weight of 700 or more,
More preferably, dyeing is performed using a neutral type metal-containing dye of 900 or more. The dyeing method may be any method such as liquid bath, pad steam drying, pad dry drying, etc., and is not particularly limited.

Now, the neutral type metal-containing dye with a molecular weight of 700 or more used in the present invention refers to a so-called 2:1 type metal complex dye in which two dye molecules have coordinate bonds with two metal atoms. or sulfonemethyl groups, or asymmetric or symmetrical metal-containing dyes having a small number of sulfonic acid groups.

All of these neutral metal-containing dyes are designed to strengthen the bond with the dyed material by forming complex salts between the dye molecules and metal atoms such as chromium, and when used on ordinary fibers, high fastness properties can be obtained. However, the ultrafine fiber of the present invention, especially 0.01
For ultra-fine fibers of denier or less, the fastness is very poor if only such dyes are used, and synthetic solvent-based dry cleaning treatment containing charge soap is not recommended. For example, it has the disadvantage that almost all colored hues can be handled.

However, after dyeing with such neutral metal-containing dyes, if a fixation treatment is performed using a combination of tannins such as gallotannin (tannic acid) and metal salts such as potassium antimonyl tartrate (tartarite), in the case of ordinary fibers, Surprisingly, this treatment, which is completely ineffective and unnecessary, has a very large effect on the ultrafine fibers of the present invention, especially ultrafine fibers of 0.01 denier or less, and forms a grain surface. Ultrafine fibers and PEG-based polyurethane can be colored with high durability, and it has become possible to have excellent fastness against dry cleaning using synthetic solvents (percres), which is said to have the highest cleaning power. .

Such fixing methods can be carried out by treating dyed fibers or fiber sheets with a two-step two-bath method using tannin and metal salts, or by a dip drying method in which dyed fibers or fiber sheets are impregnated with a tannin solution, dried, then impregnated with a metal salt solution, and dried. May be processed.

Regarding the processing temperature when processing with the two-stage two-bath method, 25
The treatment can be carried out within the range of ~100°C, but if the temperature is too low, the adsorption rate of the fixing agent to the ultrafine fibers will decrease, and if the treatment temperature is too high, some of the dyed dye will be lost. Since there is a tendency for the fiber sheet to fall into the treatment liquid or to shrink, a temperature range of 30 to 85°C, particularly a range of 40 to 65°C is preferable. Also, within this processing temperature range,
The desired fixation effect can be obtained.

The fiber sheet obtained in this way is further coated with, if necessary,
After the dyeing and fixing treatments, treatments such as washing and application of a finishing agent may be performed. Further, the above-mentioned leather-like sheet may be subjected to a binder such as polyurethane and a raised treatment such as puffing before or after the dyeing and fixing treatment.

Alternatively, it may be finished by being rubbed with a tumbler or the like.

[Examples] The following examples are provided to clarify the present invention, and the present invention is not limited thereto.

In the examples, parts and percentages are by weight unless otherwise specified.

Example 1 A copolymer of acrylic acid and styrene (hereinafter referred to as As resin) was composed of 67 parts as a binding component and nylon 6 as an ultrafine fiber component in a ratio of 33 parts, with 7 island components in one filament, Furthermore, 1200 m of polymer mutually arranged fibers in which a large number of ultra-fine fiber components are interposed in the island components were added.
After spinning at a speed of /min, the fibers were drawn 2.6 times and crimped to obtain staples of polymer interlayer array fibers having a fiber length of 51 mm and a denier of 4.0. When the fibers were made into ultra-fine fibers, the average fineness as ultra-fine fibers was 0.002 denier.

The staples were threaded through a card and a cross wrapper to form a garment, and then needle punched using a needle with one hook to entangle the polymer interlayer fibers to produce a nonwoven fabric. . The basis weight of non-woven fabric is 450
g/m2, and the apparent density was 0.18 CI/cnf. Both sides of this non-woven fabric have pores with a diameter of 0.25 mm and a pitch of 2.
High-speed fluid streams were injected twice each from nozzles arranged in a row of 5 mm while vibrating the nozzles at a pressure of 100 h/-. The obtained nonwoven fabric had a fiber structure in which the polymeric mutually arranged fibers were branched into ultrafine fibers or bundles thereof, and were densely intertwined with each other (distance between fiber entanglement points @50μ).

Next, the nonwoven fabric was shrunk and dried in hot water at 85°C, and then passed through a heated roll to smooth the surface.

Thereafter, polycaprolactone glycol having a molecular weight of about 2000 was used on one side of the sheet, and diphenylmethane-4
, 4'-diisocyanate, and then a polyurethane solution containing 10 parts of lysine-triisocyanate as a crosslinking agent based on the solid content of the polyurethane was added to a crosslinked polyurethane chain-extended mainly with 1,4-butanediol. Peel strength 3.5] q/am or more: Peeling was not possible and the polyurethane was broken. A 100% modulus of 30kc1/cnf> was applied with a solid content of 2.4g/TlI2 using a gravure coater. Then, the polyurethane was coated with a heating roll. A composite of resin and finely intertwined microfibers.

Next, on this same surface, polyoxyethylene glycol with a molecular weight of 1,600 was used to create a prepolymer with isophorone diisocyanate, and then a hard polymer with a PEG content of 25% was chain-extended with 4°4'-diaminodicyclohexylmethane and ethylene glycol. type polyurethane was applied at a solid content of 1°5g/m2. Next, it was pressed through a heated embossing roll to emboss a leather-like grain pattern.

Thereafter, the As resin was almost completely extracted and removed in trichlorethylene, and all the polymer mutually arranged fibers were made extremely fine.

The sheet-like material thus obtained was dyed and fixed using a Wins type dyeing machine under the following conditions.

Dyeing condition dye: Lanacron Navy Blue 5-
G (neutral asymmetric metal-containing dye) 10% owf Dyeing temperature x time = 95°C
After treatment at °C13C13Q, treatment was performed at 50 °C in a weakly acidic bath containing 5% owf of tartarite for 3Q.

Next, the bond was washed with hot water, treated with a finishing agent, and then softened using a tumbler and dried.

The resulting leather-like sheet material having a grain layer had no uneven dyeing, was colored a calm dark blue, and had a supple texture with a sense of unity with little repulsion. In addition, the color tone of the silver surface was deep and glossy, and the scratch resistance and bending resistance were also excellent. Also, JIS-LO
The washing and dry cleaning fastness was evaluated using LO844 and LO860 and found to be extremely good.

Example 2 A nonwoven fabric similar to that of Example 1 was used, and the same treatment as that of Example 1 was applied to create a cross-linked fiber sheet with soft segments composed of polyoxyethylene chains having an average molecular weight of about 600 on the smooth surface of a fiber sheet with one side smooth. A polyurethane solution (peel strength 5 ki/cm) prepared by adding 20 parts of hexamethylene diisocyanate trimer type crosslinking agent to the solid content of the polyurethane to PEG-based polyurethane (100% modulus 40 ki/cITf, PEG content 150%) A solid content of 3°Oq/W12 was applied. Next, the resin was pressed with a heated angle to form a composite body with the finely intertwined microfibers. After that, a hard type PEG-based polyurethane (100% modulus 290kq10f, PEG content 32%) with the same average molecular weight but a higher hard segment component ratio and lower PEG content was added to a solid content of 1.3q. /m2 gravure coater.

Thereafter, a leather-like grain pattern was embossed with a heated embossing roll, and the As resin was almost completely extracted and removed in trichlorethylene.

Using the same dyeing machine as in Example 1, the sheet-like material obtained in this way was dyed with lrgal anRed-B.
Staining and fixing treatments were performed in the same manner as in Example 1 except that rOWn RL-200% 10% OWF was used.

The obtained leather-like sheet material had a deep and clear color tone without uneven dyeing, and had a luxurious appearance.

I had this item dry cleaned at a dry cleaning store using both petroleum-based and perchloren-based solvents, but...
There was no discoloration or fading, and the cleaning resistance was very good.

Comparative Example 1.2 In Example 2, hard type PEG-based polyurethane (100
% modulus 290k11/cJ, PEG content 32%
) instead of the 100% modulus 40h/c given earlier
J, 100% PEG-based polyurethane with 50% PEG content and polylactone glycol as soft segments
A leather-like sheet material was obtained by dyeing and fixing, followed by the same treatment as in Example 2, except that the same amount of polyurethane, which was a 1:1 blend of polyurethane with a modulus of 110 ki/d, was applied (Comparative Example 1).

On the other hand, without using soft type PEG type polyurethane, only hard type PEG type polyurethane with 100% modulus 290 and 9/c JPEG content of 32% (peel strength 0.41 q/cm) was used, and the resin and dense A leather-like sheet material of Comparative Example 2 was obtained by performing the same treatment as in Example 2 except that the ultrafine fibers intertwined with the fibers were integrated into a composite.

For the silver surface of the leather-like sheet of Comparative Example 1, the dyeing speed of the PEG-based polyurethane was adjusted by mixing a non-PEG-based polyurethane, so no color unevenness occurred after dyeing. Due to the blending, the fastness was reduced, and the color of polyurethanes other than the PEG-based polyurethane faded after dry cleaning, resulting in poor fastness.

The silver surface of Comparative Example 2 used a resin with a reduced PEG content, so there was no uneven dyeing, a clear color tone, and excellent fastness. However, when such a sheet material is worn for a long period of time, it has the disadvantage that cracks occur here and there on the silver surface due to shear fatigue.

On the other hand, the product of Example 2 showed excellent durability without any damage to the silver surface even after being worn for the same period of time.

[Effects of the Invention] The leather sheet of the present invention has a grain layer consisting of a layer mainly composed of PEG-based polyurethane, densely intertwined ultrafine fibers substantially bonded by cross-linked polyurethane, and the cross-linked polyurethane. It is basically formed from a composite layer mainly composed of polyurethane and obtains a silver hue by harmonizing the robust hue of both the ultrafine fibers and PEG-based polyurethane. Only through this combination will it be possible to provide a leather-like sheet material that has a supple feel and soft texture, maintains the appearance quality of deep and vivid colors, and has excellent durability and color fastness. It became. This leather-like sheet material can be preferably used for various purposes such as artificial leather with roots for clothes, shoe uppers, belts, bags, gloves, and ball leathers.

[Brief explanation of drawings]

Figure 1 shows a cross-linked polyurethane dry film created on a polyamide film with an adhesive area of 10 m (W) x locm.
(L) is a schematic diagram when sampling is performed and peeled off from the interface. In the figure, A represents a crosslinked polyurethane dry film, and B represents a polyamide film.

Claims (5)

[Claims] (1) The distance between the upper layer (I) mainly composed of polyurethane containing 70% or more of a polyoxyethylene glycol component in the soft segment, crosslinked polyurethane, and fiber entanglement points substantially bonded by this is 200%. A leather-like sheet-like article having, on at least one side, a grain layer formed of a lower layer (II) mainly consisting of polyamide ultrafine fibers of micron size or less and/or bundles thereof. (2) Claim (1) characterized in that the average thickness of the upper layer (I) is in the range of 0.2 to 3 microns.
The leather-like sheet-like material described in 2. (3) Claim (1) characterized in that the polyoxyethylene glycol component in the polyurethane of the upper layer (I) accounts for 40% or less of the total constituent components of the polyurethane. or (2). (4) Any one of claims (1) to (3), characterized in that the adhesive strength of the cross-linked polyurethane constituting the lower layer (II) is 1.0 kg/cm or more. The leather-like sheet material described above. (5) A method for producing a leather-like sheet material, characterized by combining at least the following steps [1] to [5]. [1] Obtaining a fiber sheet mainly consisting of ultrafine fibers or multicomponent fibers made of at least two types of polymeric substances, which can be formed into ultrafine fibers by mechanical manipulation or chemical treatment. Step [2] Spraying a high-speed fluid stream onto at least one surface of the fiber sheet to branch and/or entangle the fibers [3] Applying cross-linked polyurethane to the surface sprayed with the high-speed fluid stream. Step [4] Step of applying polyurethane containing 70% or more of polyoxyethylene glycol component in the soft segment to the cross-linked polyurethane-applied surface [5] Dyeing mainly ultrafine fibers using a neutral metal-containing dye After that, a process of fixing with tannins and metal salts.