JPH0418341A - Leather powder-contaiing film or sheet and laminate using same - Google Patents

Abstract

PURPOSE:To enhance appearance, the touch and long-term properties while keeping the original hygroscopicity, moisture release properties and moisture permeability of leather by using an ultrafine leather powder reduced in impurity and having a specific particle size. CONSTITUTION:A leather powder-containing film or sheet is constituted of 1 - 90 wt.% of a leather powder with cortex content of 85 wt.% or more, oils and fats content of 2 wt.% or less, the total amount of water extractable Na<+>- and Ca<2+>-ions of 0.5 wt.% or less, and average particle size D50 of 7mum or less and the standard deviation of a particle size of 3mum or less and 99 - 10 wt.% of a synthetic resin. This leather powder-containing film or sheet is constituted as a coating film or laminated to a base material directly or through an adhesive.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a leather powder-containing film or sheet and a laminate using the same, particularly to the improvement of leather powder, and is applicable to apparel, shoes, as synthetic leather, artificial leather, etc. It can be used for bags, vehicle interior materials, furniture, stationery, etc.

[Background technology]

Synthetic leather and artificial leather have traditionally been used as materials for apparel, shoes, bags, etc. In recent years, films containing leather powder made from animal hides, synthetic leathers, and artificial leathers have become known in order to bring them closer to the feel, appearance, moisture absorption, moisture release, and moisture permeability of natural leather. (For example, JP-A-63-233828, JP-A-1-314789). If the particle size of the leather powder used for these purposes is too large, the surface will be rough, the appearance will be poor, and it will be difficult to add it to the surface coating layer or impregnated layer, which will hinder commercialization. Therefore, particles with a particle size of 10 μm or less are required, and it is said that it is preferable to have a particle size as small as possible.

[Problem to be solved by the invention]

However, the leather powder used conventionally has a particle size of 40 μm or less in JP-A No. 63-233828, and a particle size of 30 μm or less in JP-A-1-314789. It is inappropriate for it to be mixed in or in sheets.

Moreover, conventionally, the amount and type of impurities other than collagen normally contained in the leather itself have not been considered.
When used for films, sheets, synthetic leather, artificial leather, etc., impurities may bleed out as white powder on the surface due to the effects of humidity, heat, etc. during long-term use or storage, which may affect the product's appearance and performance such as color fastness. There is a problem in that it causes deterioration.

The purpose of the present invention is to provide a leather powder-containing film or sheet that has improved appearance, feel, and long-term performance while maintaining the excellent properties inherent to leather such as moisture absorption, moisture release, and moisture permeability, and synthetic leather using the same. An object of the present invention is to provide a laminate of artificial leather or the like.

[Means and effects for solving the problems] The present invention provides a method for producing synthetic leather, artificial leather, etc. using leather powder.
Focusing on the fact that not only the particle size of leather powder but also various impurity components contained in the leather itself have a significant impact on product performance, especially long-term performance, we used ultra-fine leather powder with a specific particle size with few impurities. This aims to achieve the above objective.

That is, the leather powder-containing film or sheet of the present invention has a cortex content of 85 wt% or more, an oil content of 2 wt% or less, and a total amount of water-extractable Na+ ions and Ca2+ ions of 0.5.
Leather powder 1 to 90 w wt% or less, and an average particle size D50 of 7 μm or less, and a standard deviation of the particle size of 3 μm or less
t% and 99-10wt% of synthetic resin.

The laminate of the present invention is constructed by laminating the above-mentioned leather powder-containing film or sheet on a base material as a coating film, or directly or via an adhesive.

The leather powder used for the film, sheet, etc. of the present invention has the characteristic values such as cortical content limited as described above, and these limitations are due to the following reasons.

I) Cortex content of 85 wt% or more: A high content of cortical content means that the amount of impurities is small, and at the same time, it is an important substance that improves the surface condition, touch feeling, etc. of products mixed in leather, paint, etc. It means to be a factor. In other words, the surface condition of the product can be improved more efficiently with a smaller amount of powder when the amount of cortical material is larger.

2) Oil and fat content of 2 wt% or less (preferably 0.5 wt% or less): The oil and fat content present in animal leather deteriorates due to heat, etc., resulting in bad odor, coloring, and deterioration of the surface texture of the mixed product due to bleed-out (
(Causes sticky, slimy, shiny feeling). Therefore, the lower the oil and fat content, the better.

3) Free ions extractable with water (Na”, Ca”)
Total amount of 0.5 wt% or less: Among the impurities derived from leather raw materials, if the amount of free ions extracted with water is large, the product will be affected by humidity, heat, etc., and the salts ( For example, Nacl, Na2
504. CaSO4, etc.) bleed out, leading to deterioration of product appearance. In addition to cations such as Na'' and Ca2+, free ions that can be extracted with water include Cl.
``-, 30, 2- anions exist, but the ones that bleed out are only in the form of salts of the counter ions of these ions, so the cation Na, which is a small amount,
It was defined as the total amount of + and Ca2+.

4) Average particle diameter D5o≦7μm and standard deviation σ≦3μm
: Particle size is a decisive factor for thin-walled products; if the particle size is large, it will lead to defects due to poor dispersion and deterioration of surface texture (roughness, unevenness). On the other hand, the smaller the particle size, the better the dispersion, and a product with less product defects (voids, thread breakage, etc.) and a surface condition with a good touch feel can be obtained. Furthermore, a small standard deviation means that there are few large particles mixed in in the distribution.

The method for measuring the above characteristic values is as follows.

A) Cortex and oil/fat content: JIS K6550-1976 r Leather Test Method J6.
7 and 6.4.

Total amount of free ions (Na'', Ca'') extractable with old water: 10 g of dry leather powder was stirred in 1007 rL of pure water all day and night to extract free ions in the leather powder. Na in the extract
++ Ca2+ is determined by atomic absorption spectrometry and determined as the amount extracted from leather powder.

C) Distribution of average particle size and standard deviation - Disperse several tens of mg of leather powder in 100-methanol, measure the particle distribution with a Coulter Counter (manufactured by Coulter Electronics), and calculate the average particle size and standard deviation. Find the deviation.

Note that the density range of leather powder is usually 0.38 to 0.43 g/
cc (after drying leather powder at 120℃ for 2 hours, JIS K6
721). If the density is too high, the particle size will increase and exceed the predetermined average particle size of 7 μm. On the other hand, if the density is too small, the leather powder will become fibrous or have many loose hairs, making it difficult to uniformly coat the synthetic resin. This is because it may become difficult to disperse.

The leather powder according to the present invention as described above can be produced by, for example, processing the leather powder raw material by coarsely pulverizing, drying, degreasing with a solvent, removing residual solvent, washing with water, dehydration, swelling treatment with steam, drying, finely pulverizing, and converting fine powder into coarse powder. After carrying out each step of classification with the powder, a step of re-pulverizing the fine powder to an average particle size D50" of 7 μm or less, and a step of re-pulverizing the fine powder with an average particle size D50" of 7 μm or less, and a D50"
It can be manufactured by performing a step of classifying and removing fine powder of 2 μm or less.

To explain this manufacturing method in more detail, first, in order to facilitate fine pulverization in the subsequent process, the leather powder raw material is coarsely pulverized to a particle size of about 10 mm or less using a pulverizer such as a show crusher, cutter mill, or hammer crusher. The coarsely crushed leather powder thus obtained usually contains 40 to 60 wt% of water. Note that shaving waste leather, floor leather, etc. can be used as the raw material for the leather powder.

Next, in order to facilitate degreasing (removal of fats and oils) in a subsequent step, this water-containing coarse powder is dried until the moisture content is approximately 20 to 30 wt%.

Next, this dry coarse powder is mixed with an appropriate solvent to dissolve 2w of oil and fat.
Degreasing is performed until the content is t% or less, preferably 0.5wt% or less. Here, n-hexane, benzine, methylene chloride, acetone, ethyl acetate, toluene, etc. can be used as the degreasing solvent.

Subsequently, in order to remove residual solvent in the coarse powder, the coarse powder after degreasing is heat treated. For safety reasons, steam is usually used as the heat source, so this process is also called steam purging. Other heat sources that can be used include heated nitrogen and heated air.

Next, free ions (Na”, Ca2
In addition to extracting and removing the strawberry, a water washing process and a dehydration process are performed in order to make the coarse powder retain a predetermined amount of moisture. It is effective to repeat this series of water washing operations several times in a batch manner. For example, a fixed amount of water is supplied to the coarse powder after the solvent has been removed, and after stirring for a desired time and bubbling with air if necessary, dehydration is performed. Depending on the amount of water supplied, it is usually done several times.
Preferably repeat 3 to 4 times. Continuous water washing operation requires a large amount of water and is not advantageous, but it is possible.

Dehydration is usually carried out by filtration (draining or draining) for ease of operation, or may be carried out by other methods such as centrifugal dehydration.

The water temperature may be room temperature, preferably 30°C or lower.

Through the above series of water washing operations, the total amount of free Na'' ions and Ca2+ ions (dry weight equivalent) was reduced to 0.5.
A water-containing coarse powder having a water content of usually 65 to 70% can be obtained when the amount is less than wt%. As a result of this series of water washing operations, the coarse powder usually retains a predetermined moisture content (65-70%), so this method only requires checking the moisture content of the coarse powder after dehydration, which has not been done in the past. This method has the advantage that the humidity conditioning step of replenishing water until the coarse powder after removing the solvent reaches a predetermined moisture content can be virtually eliminated.

Here, the reason why a predetermined amount of water is retained or supplied to the coarse powder is as follows. That is, in a dry state, even if pulverization is performed after steam steaming in the next step, pulverization will not proceed.

However, when steam-cooked coarse powder that contains water and is swollen, it is partially denatured by heat, and when dried, it becomes compact and hard, making it easier to crush and pulverize.

Next, in order to facilitate fine pulverization in the subsequent process, the coarsely crushed leather powder after dehydration is stirred and then subjected to a swelling treatment (steam cooking) using steam.

Subsequently, in order to facilitate fine pulverization in the subsequent step, the coarsely crushed leather powder after the swelling treatment is dried until the moisture content is approximately 3 wt % or less. This drying step is usually performed by combining preliminary drying using a dryer and main drying using a vacuum dryer.

Next, in order to facilitate re-pulverization in the subsequent process, the coarsely crushed leather powder after drying is processed using a Victory mill, ball mill, colloid mill, etc.
Finely pulverize using a dry pulverizer such as a jet mill, roller mill, or hammer mill until the average particle size is approximately 50 μm.

Next, for the same reason, the obtained finely pulverized leather powder is passed through a gravity classifier; an inertial classifier; a centrifugal classifier such as a cyclone or a micron separator; = 30 μm or less) and coarse powder (
For example, D50=60 μm or more). Incidentally, the coarse powder can be recycled to the pulverization step if necessary.

Subsequently, the fine powder is re-pulverized until it becomes D5o-7 μm JJ or less, and then the fine powder with D50=7 μm or less is obtained. A process of classifying and removing fine powder of 2 μm or less is performed. The re-pulverization step can be carried out using a dry pulverizer suitable for pulverization, such as a shet mill or a colloid mill, among the dry pulverizers mentioned above. Further, the classification step can be carried out using a classifier as described above.

In the above method, a series of water washing operations were performed after the degreasing step, but this water washing operation can also be performed before degreasing or after pulverization.

The synthetic resin used in combination with the leather powder obtained as described above may be thermoplastic or thermosetting. Typical thermoplastic resins include vinyl chloride resin, vinyl acetate resin, polystyrene, ABS resin, acrylic resin, polyethylene, polypropylene, fluororesin, polyamide resin, acetal resin, polycarbonate, urethane resin, thermoplastic elastomer such as ester resin, There are cellulose plastics, etc. Typical thermosetting resins include phenol resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, diallyl phthalate resin, thermosetting polyurethane resin, and silicone resin.

The composition of the present invention may contain additives commonly used in this field, such as fibers, antioxidants, ultraviolet absorbers, plasticizers, stabilizers, etc., depending on the purpose of quality stabilization and the usage environment. , processability improvers such as lubricants; fillers; coloring agents such as dyes and pigments, etc. can be added in necessary amounts.

Fibers include natural fibers such as cotton, linen, silk, wool, rayon, cupro, polyester, polyethylene, polypyrene, polyurethane, vinylon, acrylic, nylon, etc.
Examples include chemical fibers such as acetate and polyvinyl chloride.

As antioxidants, alkylphenols, alkylenes,
Bisphenol, alkylphenol thioether,
Examples include β, β'-thiopropionate, organic phosphite, aromatic amine, and phenol/nickel complex.

As ultraviolet absorbers, salicylic acid esters such as phenyl salicylate, hydroxybenzophenones such as 2-hydroxyhensitrial: 2-hydroxyhensiphenone, 2-hydroxy-4-methoxyhensiphenone, 2-hydroxy Hydroxyhensiphenones such as -4-octoxybenzophenone and 2,2-dihydroxydi-4-methoxyhensiphenone are available.

Processability improvers for vinyl chloride include plasticizers such as dioctyl phthalate, dibutyl phthalate, tricresyl phosphate, trioctyl phosphate, tribasic lead sulfate, lead stearate, and dibasic lead phosphite. and lubricants such as stearic acid, lead stearate, and carnauba wax.For polyurethane, dimethylformamide,
Solvents include methyl ethyl ketone and inpropyl alcohol.

Examples of fillers include calcium carbonate, titanium white, clay, and mica.

In order to make the leather powder-containing film or sheet of the present invention, when pellet-shaped, powder-shaped, block-shaped or paste-shaped resin is used, in order to prevent foaming and powder hydrolysis during heating and mixing or kneading, Reduce the moisture content of the flour to 0.5
wt%, and the dried leather powder, resin, and additives if necessary are mixed or kneaded under heating, processed into pellets, powder, etc., and then formed into a film or sheet. Alternatively, it may be made into a liquid composition. In this case, the resin is dissolved or dispersed in a suitable solvent, the leather powder and additives are added thereto if necessary, stirred and mixed, and then formed into a film or sheet. do. In either case, the mixing ratio of leather powder and synthetic resin is in the range of 90 to 1 wt% of leather powder to 10 to 99 wt% of synthetic resin. If the proportion of leather powder exceeds 90 wt%, the film or sheet will become brittle, and if it is less than 1 wt%, the addition effect will be ineffective. However, the leather powder content in the synthetic resin is 5 to 1 in the case of film.
0 wt% is preferable, and in the case of a sheet, 10 to 60 w
t% is preferred.

The thickness of the film or sheet is suitably at least 5 μm, and the leather powder is preferably uniformly dispersed.

In addition, leather powder may be exposed on the surface, and in this case, it is useful to further improve the touch feeling and the sense of warmth.

As a forming method, dry film forming, wet film forming, calendar molding, inflation molding, T-die molding, press molding, etc. can be used.

The above-described leather powder-containing film or sheet can be used by itself, but it can also be used for various purposes by laminating it on a base material by the method described below. In addition, surface finishing can be performed by puffing, embossing roll processing, etc., if necessary. Examples of the base material used here include woven fabrics, knitted fabrics, and nonwoven fabrics made of natural or chemical fibers as described above, as well as synthetic resin films or sheets, other leather powder-containing films or sheets, and paper.

When using polyurethane resin as a lamination method,
A method of impregnating a base material with a resin solution containing leather powder, a wet method of applying the solution to the base material, or a method of making a leather powder-containing film or sheet with the solution etc. and applying it directly or through an adhesive to the base material. One example is the dry method of laminating layers. In the case of polyvinyl chloride resin, a method may be used in which a film or sheet is produced by extrusion molding or calendar molding from a heat-melted resin containing leather powder, and the film or sheet is laminated onto a base material that has been previously coated with an adhesive and dried.

A specific laminating apparatus is shown in FIGS. 1 to 3. FIG. 1 shows a dry coating device in which a dry coating liquid 2 consisting of a resin solution containing leather powder is coated on a release paper l to a desired thickness by a knife roll 3, dried in a dryer 4, and then cooled by a cooling roll 5. The leather powder is then cooled to form a leather powder-containing film or sheet.

Next, after an adhesive 6 is applied to the surface of this film or sheet, it is laminated with a separately supplied base material 7 (which may be impregnable or non-impregnable) in a nip roll 8, and dried in a dryer 9. It is further cooled by a cooling roll 10 to form a laminate 11.

FIG. 2 shows an impregnating coating apparatus, in which an impregnable substrate 20 is introduced into an impregnating tank 2, where it is impregnated with an impregnating coating liquid 22 made of a leather powder-containing solution, and then the excess liquid is squeezed out by a mangle 23. After that, the coagulation and washing tank 24
is introduced into the interior, where it is coagulated and washed with water 25,
It is further dried by a dryer 26 to form a laminate 27.

FIG. 3 shows a wet coating device similar to the device shown in FIG. The laminate 40 is sequentially introduced into a laminate 40, solidified and washed with water 36, 37, and 38, and further dried in a drier 39 to form a laminate 40.

The manufacturing process of the film or sheet and laminate according to the present invention as described above is summarized in FIG. 4.

〔Example〕

The present invention will be explained in more detail below with reference to Examples.

Actual JL Example (Leather powder-containing film) Production of leather powder: Lump 12 of chrome-tanned cowhide waste leather (schiebink leather)
00kg is crushed using a crusher (manufactured by Hosokawa Micron) to the original shape of the shaving waste leather (max: lam width x 1
After loosening it into pieces (2 cm long), they were sequentially fed into a coarse crusher (manufactured by Odate Co., Ltd., 1 mm mill: capacity 600 kg/Hr),
Crushed leather powder with a particle size of about 10 mm or less. The moisture content of this coarse powder was 40 to 60 wt%.

Next, 350 kg of this wet coarsely crushed leather powder is placed in a vacuum dryer and dried until the moisture content becomes 20 to 30 wt%. Subsequently, 270 kg of this dry coarsely crushed leather powder was put into a degreasing machine,
While feeding n-hexane at 100 f/min, the mixture was stirred for 1 hour and 15 minutes, extracted, defatted, and filtered. The residual fat and oil content CtO in the obtained coarse defatted powder was 5 wt% or less.

Next, the remaining solvent in this defatted coarsely crushed leather powder was heated at 130'C.
Purge with 2 kg/crl G steam until the solvent (hexane) odor disappears.

The same degreasing machine was replenished with 2rn' of water at room temperature, and after stirring for 30 minutes, the water was drained by filtration. This water washing operation is carried out a total of four times to remove free ions such as metal ions and water-soluble components in the waste leather. Crushed leather powder after a filtration and draining is 65-7
It contained 0 wt% water.

Next, this is transferred to a steam steamer without adjusting the humidity, and is steamed for 45 minutes at 130°C with 2 kg/crjG steam without stirring.

Next, the coarsely crushed leather powder after steaming was pre-dried in a dryer maintained at 90°C for 3 hours until the moisture content was 30-40wt%, and then dried in a vacuum dryer at 45°C for 8 hours to reduce the moisture content to 1wt%. Obtain 190 kg of dry coarsely crushed leather powder.

Next, this was pulverized using a Fine Victory Mill (manufactured by Hosokawa Micron Corporation) at 1700 rpm for 2 hours.

Subsequently, this was classified using a cyclone classifier to obtain 35 kg of fine leather powder with an average particle size of I) 50 to about 30 μm.

- 155 kg of coarse leather powder of approximately 60 μm are obtained.

Incidentally, the coarse leather powder having a D50'' of about 60 μm was circulated to the above-mentioned pulverization step.

Furthermore, 35 kg of this leather powder with a D50 of about 30 μm was milled in a shet mill (manufactured by Seishin Enterprise Co., Ltd.) at an air pressure of 8 kg.
/cnf G , air flow rate of 10 rn'/mim, and throughput of 20 kg/Hr until the total amount becomes D50≦7 μm.

Finally, this was classified using a cyclone (manufactured by Seishin Enterprise Co., Ltd.) to yield 33° and 25 kg of ultrafine leather powder with D5°≦7μm. - 1.75 kg of ultrafine leather powder (in Noheg filter) of less than 2 μm is obtained.

The production of leather powder-containing films is thus obtained. The properties of ultra-fine leather powder (hereinafter referred to as leather powder A) with a particle size of ≦7 μm are shown in Table 1 below.

Next, a polyurethane solution for synthetic leather (Zamine ME-3612LP manufactured by Dainichiseika Chemical Co., Ltd.) was mixed with a resin solution (resin solid content 20 wt%) so that the dry leather powder A was 10 wt% with respect to the solid content of 90 wt%. ) is applied onto release paper using a coater and dried at 70°C to produce a 30 μm thick film.

LLLL (Leather powder-containing film) A film is produced using the same film production method as in Example 1, except that the dry leather powder A is mixed at 30 wt% with respect to the solid content of 70 wt% of the polyurethane solution.

Example 3 (Leather powder-containing film) A film was produced in the same manner as in Example 1, except that dry leather powder A was mixed to a solid content of 50 wt % in the polyurethane solution so that the dry leather powder A became 50 wt %.

Example 4 (Leather powder-containing sheet) Soft hinyl chloride resin (manufactured by Shin-Etsu Polymer Co., Ltd., plasticizer 38w)
(containing t%, average degree of polymerization 3000) 80 wt%, 20 wt% of dried leather powder A was mixed therein, heated and kneaded at 160°C, processed into a sheet, and pelletized. Next, this pellet was molded into a sheet with a thickness of 400 μm using a press molding machine.

JL-(Dry synthetic leather) Using the dry coating device shown in Figure 1, coat it on the release paper.
As a dry coating liquid, a dry coating polyurethane resin solution containing 6 wt% of dry leather powder A on a solid basis, with a small amount of auxiliary agent added, was applied, and dried at 130°C to form a coating of 20 μm.
A polyurethane film containing leather powder with a thickness of
Using a blended polyurethane adhesive, it was adhered to a base material made of polyester nonwoven fabric of 1 denier and a basis weight of 70 g/m', and dried at 140°C to produce dry synthetic leather having a 40 μm thick layer of polyurethane resin containing leather powder. Manufactured.

Example 6 (Wet-processed synthetic leather) Wet-processed polyurethane resin in which 30 wt% of dry leather powder A was mixed on a solid basis as a wet-processed coating liquid to a base material made of a woven fabric of blended fibers of 50% nylon and 50% Tetron. A small amount of filler added to the solution was applied using the wet coating device shown in Figure 3, and dried at 140°C to give a coating of 0.7
A wet synthetic leather having a layer of leather powder-containing ester-based polyurethane resin having a thickness of mm was produced.

Real JL 剋7 (artificial leather) Dry leather powder A is applied as an impregnating coating liquid to a base material made of polyester nonwoven fabric with a 2 denier and a basis weight of 70 g/m.
A solution prepared by adding 3 parts of a filler to an ester-based polyurethane resin solution (resin solid content 15 wt%) containing 25 wt% of the solid content of It was impregnated and dried at 130°C.

Next, a wet coach ink liquid is applied to this impregnated base material.
The same filler and foaming agent as above were added to an ester-based polyurethane resin solution (resin solid content 15 wt%) containing 30 wt% dry leather powder A on a solid basis, and the liquid was added using the wet coach ink device shown in Figure 3. Coating and drying at 130°C until 0.
An artificial leather with a porous polyurethane resin layer 4+nm thick was produced.

Comparative Example 1 A film was produced in the same manner as in Example 1 except that leather powder A was not used.

Comparative Example 2 Crushed leather powder after steam purging was directly transferred to a steamer without washing with water, and the moisture content of this coarse powder was 65 to 7.
D
Ultrafine leather powder with sa≦7μm (hereinafter referred to as leather powder B)
was manufactured. The properties of leather powder B are shown in Table 1 below.

Next, a film is produced in the same manner as in Example 1 using dried leather powder B instead of dried leather powder A.

Comparative Example 3 D5o-approximately 30μ was produced according to the same leather powder production method as in Example 1, except that the re-pulverization step and the subsequent classification step were not performed.
Leather powder of m (hereinafter referred to as leather powder C) was produced. The properties of leather powder C are shown in Table 1 below.

Next, a film is produced in the same manner as in Example 1 using dried leather powder B instead of dried leather powder A.

Sheets or laminates were produced according to Examples 4 to 7, respectively, except that leather powder A was not used.

Next, the films, sheets, and laminates obtained as described above were tested for performance such as moisture permeability and moisture absorption. The results are shown in Table-2 and Table-3.

The test method is as follows.

(1) Moisture permeability According to JIS K6549.

(2) Moisture absorption One side of the sample that has reached an equilibrium state at 23°C and 30% RH (in the case of a single layer, either side is fine, or in the case of a sample composed of two or more layers, the opposite side to the substrate) surface) at 23℃, 80%
Measure the weight increase when placed in an RH environment.

(3) Weight loss when one side of the sample that reached equilibrium at 23°C and 80% RH (the measuring cotton was the same as for the moisture absorption) was placed in an environment of 23°C and 30% RH. Measure.

(4) Touch feeling Compare by touching the surface.

(5) Humidity test Observe changes in the surface after being exposed to an environment of 30° C. and 95% RH for 24 hours.

Table 2 [Effects of the Invention] According to the present invention as described above, the appearance, feel, and long-term performance are improved while maintaining the excellent properties inherent to leather such as moisture absorption, moisture release, and moisture permeability. It is possible to provide a film or sheet containing leather powder and a laminate of synthetic leather, artificial leather, etc. using the same.

[Brief explanation of drawings]

Figures 1 to 3 show examples of a dry coating device, an impregnation coating device, and a wet coating device, respectively, for manufacturing the laminate of the present invention. FIG. 4 is a manufacturing process diagram of an example of a leather powder film or sheet and a laminate according to the present invention. ■...Release paper, 2,22.33...Coating liquid or leather powder-containing resin solution, 3...Knife roll, 4゜26.39-...Dryer, 5.10-...Cooling roll ,
7°20.30...Base material, 11. 27. 40...
・Laminated body, 22... Impregnation tank, 24, 33, 34.35
...Coagulation and washing tank, 25, 36, 37. 38...Water. Diagram

Claims (2)

[Claims] (1) Cortex content is 85 wt% or more, oil content is 2 wt% or less, total amount of water-extractable Na^+ ions and Ca^2^+ ions is 0.5 wt% or less, and average particle size D_5_
1 to 90 wt% of leather powder whose diameter is 7 μm or less and the standard deviation of the particle size is 3 μm or less, and 99 to 10 wt% of a synthetic resin.
A film or sheet containing leather powder, characterized in that it consists of %. (2) A laminate obtained by laminating the leather powder-containing film or sheet of claim (1) on a base material as a coating, or directly or via an adhesive.