JPH03162500A - Leather powder-containing resin composition, leather-like molding and production thereof - Google Patents

Abstract

PURPOSE:To obtain the subject composition capable of providing the subject leather-like molding excellent in hygroscopicity and visual appearance by blending an animal leather powder and a thermoplastic resin respectively having specified physical properties in a specified ratio. CONSTITUTION:An objective composition containing (A) 10-60wt.% animal leather powder having <=250mum average diameter and <=5 pts.wt. weight loss when extracted by water at normal temperature for 10min. and (B) 90-40wt.% thermoplastic resin composed of a straight chain low-density polyethylene or polyurethane, etc., having <=200 deg.C moldable temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a leather powder-containing resin composition used for interior materials of vehicles such as automobiles, such as handle grips. The present invention also relates to a leather-like molded article obtained using this leather powder-containing resin composition and a suitable manufacturing method thereof.

[Conventional technology]

As a thermoplastic resin, linear low-density polyethylene or polyurethane can be molded alone and used as a material for grips such as handle grips.

However, in this case, the hygroscopicity of the molded product is not sufficient, and the hands that hold the grip tend to sweat, which causes practical problems such as the surface of the molded product becoming sticky. Therefore, leather powder is mixed into the thermoplastic resin. For example, a condensed natural leather made by mixing and integrating natural leather powder and a binding material such as a thermoplastic resin was published in Japanese Patent Application Laid-Open No. 53-121.
It is described in Publication No. 90. Here, polyurethane and the like are listed as thermoplastic resins.

In addition, leather-like molded products containing a thermoplastic resin such as vinyl chloride and fine powder of dried leather powder (protein powder) and pellets for molding thereof are disclosed in JP-A-63-11311 and JP-A-63-152698. It is stated in the official bulletin. These are leather-like molded products made by pulverizing natural leather into a thermoplastic resin fabric, and adding a steam heating process to the natural leather during the pulverization process to ensure that the leather tissue is heated within a range that does not melt the leather structure. These are pellets for molding leather-like molded products that bring about a change in protein composition due to swelling.

However, when kneading synthetic resin and leather powder for these pseudo-natural leathers and leather-like molded products, even if the leather powder is dried in advance, if the kneading temperature approaches 200°C, a bad odor will occur and the resulting Pellets and molded products also emit a foul odor.

[Problem to be solved by the invention]

The present invention aims to provide a leather powder-containing resin composition in which the odor of the synthetic resin and leather powder during kneading and the odor of the kneading proboscis after kneading is reduced. Another object of the present invention is to provide a leather-like molded product with excellent hygroscopicity and appearance using this leather powder-containing resin core. A further object of the present invention is to provide a suitable method for producing the leather-like molded article. [Means for Solving the Problems] As a result of extensive research in order to solve the above problems, the present inventors have found that a leather powder-containing resin composition consisting of a specific animal leather powder and a specific thermoplastic resin is used. As a result, the inventors found that the object was achieved and completed the invention.

That is, the present invention provides animal leather powder with a weight loss of 5 wt % or less when extracted with water at room temperature for 10 minutes and an average particle size of 250 μm or less, and a shapeable temperature of 2.
The present invention provides a leather powder-containing resin composition comprising 90 to 40 wt% of a thermoplastic resin having a temperature of 00°C or lower.

The present invention also provides the above-mentioned leather powder-containing resin composition.
The present invention provides a leather-like molded product that is molded at a temperature of 'c or less.

The leather powder-containing resin composition of the present invention consists of animal leather powder and a thermoplastic resin.

The animal leather powder (protein powder) used in the present invention has a weight loss of 5w when extracted with water at room temperature for 10 minutes.
% or less, and the average particle size is 250 μm or less. If the m amount exceeds 5 wt % when extracted with water at room temperature for 10 minutes, a foul odor will be generated significantly during heating and kneading with the thermoplastic resin. Also obtained is the leather powder-containing group Ji! Even objects and leather-like molded products have a remarkable odor. Also, the average particle size is 250am
If it exceeds this value, the surface of the molded product will become rough due to poor dispersion of the leather powder, resulting in poor appearance.

Here, the extraction of the leather powder with water at room temperature is performed according to the flowchart shown in FIG.

That is, first, the leather powder is usually dried at 110 to 130°C, preferably 115 to 125°C for 2 hours or more. This dried leather powder is weighed in terms of Ig.

Also, usually 100g of pure water is weighed. The amount of pure water is preferably 50 to 200 g, particularly preferably 80 to 120 g, per 1 g of dry leather powder for uniform stirring. If there is too much, it will take too long to boil. Next, the above leather powder is added to the above pure water and stirred for 10 minutes. Thereafter, it is filtered using filter paper 5C. At this time, it is preferable to add pure water to the container so that no leather powder remains in the container. The filtrate is collected in a glass container containing zeolite, and the glass container is heated to about 200 m to boil. Boiling is performed until the pure water evaporates depending on the amount of pure water used.

It is usually carried out for F time, preferably 30 minutes to 2 hours.

The resulting extract is then dried at 110-130°C for about 1 hour. Furthermore, the container is left at room temperature and cooled for usually 30 minutes to 2 hours so that the container is sufficiently cooled in a desiccator. Then, measure the weight of the dried extract obtained. The ratio of the weight of this extract to the weight of the original leather powder (1 g) is the weight loss when extracted with water at room temperature for 10 minutes. In addition, although the stirring time was 10 minutes here,
It may be 5 to 20 minutes.

Such animal leather powder can be suitably obtained, for example, by using leather shaving waste as a raw material and washing the crushed product with water at room temperature for about 20 minutes.

Figure 2 is a flowchart showing the general tanning process.
Leather shaving waste, which serves as a raw material, is obtained by shaving during the tanning process shown in FIG. As the leather shaving waste, shaving waste obtained in the tanning process of cowhide, pigskin, etc. is preferably used. Further, the thermoplastic resin used in the present invention has a moldable temperature of 200° C. or lower. Molding temperature is 200
If the temperature is below 0.degree. C., the leather powder will not decompose when molding a leather powder-containing resin composition consisting of this resin and the animal leather powder.

Examples of such thermoplastic resin include ili! Examples include chain low density polyethylene (L-LDPE), polyurethane, polybutene-1, high density polyethylene (DPE), polypropylene (PP), vinyl chloride resin (PVC), and low density polyethylene (LDPE). Among these, polyurethanes such as linear low density polyethylene (L-LDPE) or urethane elastomers are particularly preferred.

The leather powder-containing resin composition of the present invention comprises 10 to 60 wt% of the above animal leather powder and 90 to 40 wt% of the above thermoplastic resin.
It consists of %. If the amount of animal leather powder is less than 10 wt%, sufficient moisture absorption and desorption performance will not be obtained, and the molded product obtained from this composition will have a sticky surface and will be defective. Also 60wt%
If the temperature exceeds this value, the molded product obtained will have a rough surface and will be defective.

A non-whitening modifier may be added to the above leather powder-containing resin composition, if necessary. Examples of non-whitening modifiers include:
Like modified olefin resin using maleic anhydride,
An adhesive binder is preferably used to improve the interfacial affinity between the resin and the filler leather powder. The amount added is usually 15 parts by weight per 100 parts by weight of the thermoplastic resin and leather powder.
Parts by weight or less, particularly 3 to 10 parts by weight, are preferred. If the amount exceeds 15 parts by weight, the appearance of the resulting molded product may deteriorate.

The leather-like shaped article of the present invention is formed by molding the above leather powder-containing resin composition at a temperature of 200° C. or lower.

The leather-like molded article of the present invention can be easily produced by the following method. In other words, the weight loss when extracted with room temperature water for 10 minutes is 5.
A leather powder-containing resin composition consisting of 10 to 60 wt% of animal leather powder having an average particle size of 250 μm or less and 90 to 40 wt% of a thermoplastic resin having a moldable temperature of 200° C. or less is kneaded and granulated. After that, it is molded at a temperature of 200°C or less.

First, the leather powder-containing resin Mi is kneaded.

Thermoplastic resin 40-90wt% and leather powder 60-1Qw
It is preferable to mix t% uniformly by kneading with an extruder, Banbury mixer, etc. Here, it is preferable that the thermoplastic resin be melted at the same time as kneading or beforehand. Further, it is preferable that the leather powder is dried in advance and its water content is 3 wt% or less. Moisture content of leather powder is 3w
If it exceeds t%, air bubbles may be generated in the kneaded product or hydrolysis of the leather powder may occur, resulting in a decrease in the strength of the resulting molded product. Drying is preferably carried out at 120° C. for 2 hours or more, for example. By using the leather powder dried in this way, it is possible to reduce the bad odor of the U-Kaimono during and after kneading.

During this kneading, a non-whitening modifier may be added to the leather powder-containing resin composition as desired. By adding this non-whitening modifier, the molded product obtained from this composition becomes difficult to bend and whiten.

Next, the obtained kneaded material is pelletized using a pelletizer or the like to granulate it.

Next, it is preferable to pre-dry the granular leather powder-containing resin composition obtained by kneading and granulating.

In order to prevent the leather powder mixed in the granular leather powder-containing resin composition from being hydrolytically degraded due to moisture, it is pre-dried. By preventing hydrolytic deterioration of the leather powder during molding, it is possible to further reduce the bad odor of the composition and molded product during molding.

Pre-drying may be carried out so that the moisture content of the granular leather powder-containing resin composition is Iht% or less. If it exceeds 1.5%, not only the strength of the molded product obtained will decrease, but also silver streaks may occur on the surface of the molded product, resulting in a defective product. Pre-drying at 100-120°C for 5-12 hours is preferred.

Next, the granular leather powder-containing resin composite sole is molded at a temperature of 200° C. or lower. For molding, ordinary injection molding machines, extrusion molding machines, rotary molding machines, etc. can be used. For example, a pre-dried granular leather powder-containing resin composition is put into a hopper of an injection molding machine, plasticized, and then injected into a mold to form a desired leather-like molded product. Alternatively, a pre-dried granular leather powder-containing resin composition may be plasticized using an extrusion molding machine and extruded through a die to form a sheet-like or hollow leather-like molded product, or a desired leather-like molded product may be formed using a rotary molding machine. or At this time, the molding temperature is 200°C or less, preferably 160 to 200°C. If the temperature exceeds 200°C, the leather powder in the leather powder-containing resin composition will decompose, which will not only reduce the strength of the shaped product but also generate a bad odor.

As described above, the leather-like molded product obtained by the present invention has little bad odor, has excellent hygroscopicity, has no sticky surface, and has an excellent appearance with no surface roughness. Also, less bad odor is generated during the manufacturing process.

〔Example〕

Hereinafter, the present invention will be explained in detail based on Examples, but the present invention is not limited thereto.

Example 1 Moretec 1018T manufactured by Idemitsu Petrochemical Co., Ltd. as linear low-density polyethylene (L-LDPE) and dried animal leather powder (protein powder) with an average particle size of 200 μm were mixed into 9
They were blended at a ratio of 0 wt% and 10 wt% to obtain a leather powder-containing resin composition. This composition was kneaded and extruded at 185° C. using a single screw extruder with a screw diameter of 50 mg to form pellets. The leather powder used here was obtained by washing coarsely crushed shaving waste obtained in the shaving process during the cowhide tanning process with room temperature water for about 20 minutes; The weight loss after 10 minutes of extraction was 4.
It was 5%.

Next, the pellets were pre-dried at 120"C for 5 hours, and then molded at 185°C with an injection molding machine to form a leather-like molded product (1
00w×100mm×311m) was obtained.

In this example, the foul odor around the strand before pelletization and the foul odor of the pellets were slight. Also, the odor of the imposing items was slight. The appearance and hygroscopicity of the molded product were excellent.

In addition, the strength of JIS K7113 thickness 3II11,
When the sample for elongation measurement was bent at the center, no whitening was observed.

Examples 2 and 3 The ratio of L-LDPE and leather powder in Example 1 was 70
Pelletization and injection molding were carried out in the same manner as in Example 1, except that the t% and 30 t% and 40 t% and 60 wt% were changed, respectively.
A leather-like molded article was obtained.

Regarding the bad odor, the results were almost the same as in Example 1. Moreover, the appearance and moisture absorption properties of the molded products were excellent. When examining the whitening upon bending, slight whitening was observed. Examples 4 and 5 In place of the L-LDPR in Examples 2 and 3, a thermoplastic polyurethane elastomer (Elaton Stran C80AIO, manufactured by Takeda Birdish Urethane Industries) was used. Using the same mixing ratio as in Examples 2 and 3, pelletization and injection molding were performed in the same manner as in Example 1 to obtain a leather-like molded product.

Regarding the bad odor, the results were almost the same as in Example 1. Moreover, the appearance and hygroscopicity of the molded product were excellent as in Examples 2 and 3. Slight whitening was observed during bending.

Example 6 L-LDPE 70wt% and leather powder 3 similar to Example 2
5 parts by weight of an adhesive resin (Boritac I {-6 2 0 0 P manufactured by Idemitsu Petrochemical Co., Ltd.) as a non-whitening modifier was added to 100 parts by weight of the RFC rostrum consisting of 0 wt%, and the same procedure as in Example 1 was carried out. A leather molded product was obtained by pelletizing and injection molding using the method described above.

Regarding the bad odor, the results were almost the same as in Example 2. However, the whitening observed in Example 2 during bending of the molded product became less likely to occur.

Example 7 A leather-like molded article was obtained in the same manner as in Example 2 except that a leather powder having an average particle size of 50 am was used in place of the leather powder having an average particle size of 200 μm in Example 2.

The results were almost the same as those of Example 2.

Comparative Example I L-LDPE (MORETECH 1018T manufactured by Idemitsu Petrochemical Co., Ltd.
) and dried animal leather powder with an average particle size of 200 μm.
Leather powder-containing resin composition blended at a ratio of wt% and 70wt%
It was made into a c-thing. This composition was mixed with a 50 mm single screw extruder for 1
The mixture was kneaded and extruded at 85°C to form pellets. The weight loss of the leather powder used here when extracted with water at room temperature for 10 minutes was 4.5%.

Next, this pellet was pre-dried at 120°C for 5 hours, and then heated to 185°C in an injection molding machine. Molded into a leather-like molded product (1
00 mm x 100 mm x 3 mm) was obtained.

At this time, the perehut and the ostentatious items also had a bad odor. In addition, the appearance of the molded product was poor, and there was severe whitening when bent. Comparative Examples 2 and 3 Animal leather powder was used that had a weight loss of 15% when extracted with water at room temperature for 10 minutes. L-LDPE (Idemitsu Petrochemical ■
(manufactured by Moatec 1018T) and dried average particle size 200
μm animal leather powder at 90wt%, 10wt% and 40wt%
A leather-like molded product (1 00
mm×10001×3m) was obtained.

At this time, the atmosphere of the strands before pelletization, the pellets, and the shaped products had a similar strong odor.

Comparative examples 4 and 5 Animal leather powder with an average particle size of 300 μm was used.

L-LDPE (manufactured by Idemitsu Petrochemical ■Moatesoku 101
8T) and dried animal leather powder with an average particle size of 300 am were made into proportions of 90 wt% and 10 wt% and 70 wt% and 30 wt%, and the berentization and injection molding were carried out in the same manner as in Example 1 to produce a leather-like molded product (100 mm x l00 aa* x3m)
I got it. The amount of tJIi when the leather powder used was extracted with water at room temperature for 10 minutes was 4.5%.

At this time, the bad odor was almost the same as in Example 1 and was slight. However, the surface of the molded product was rough and had a poor appearance.

Comparative Example 6 In place of L-LDPE in Comparative Example 1, Examples 4 and 5 were used.
Similarly, thermoplastic polyurethane elastomer was used.
The rest is leather-like in the same manner as in Leather Example 1. I got a prestigious item. At this time, the surface of the shaped product became rough and the appearance was poor. In addition, severe whitening was observed when bending. Comparative Examples 7 and 8 L-LDPE (MORETEC 1018 manufactured by Idemitsu Petrochemical Co., Ltd.
T) or a thermoplastic polyurethane elastomer was used as a single resin to produce a leather-like molded product.

Although the odor was slight, almost no heat absorbing property was obtained.

The above results are summarized in Table 1.

Here, the measurement of moisture absorption was carried out at 80m
The weight increase after the molded article was left in an atmosphere of 23° C. and 80% RH for 3 hours was converted to a value per unit area.

(The following is a blank space) [Effects of the Invention] According to the present invention, it is possible to obtain a leather powder-containing resin composition in which the bad odor of the composition during kneading of the combined resin and leather powder and the composition after kneading is reduced. In addition, by using this leather powder-containing resin composition, it is possible to obtain leather-like products with excellent hygroscopicity and appearance. Furthermore, according to the method for producing a leather-like molded article of the present invention, the above-mentioned leather-like dignified article can be suitably obtained.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing a method for extracting leather powder used in the present invention with water at room temperature. FIG. 2 is a flowchart showing a general tanning process.

Claims (1)

[Claims] 1. Weight loss when extracted with water at room temperature for 10 minutes is 5wt%
A leather powder-containing resin composition comprising 10 to 60 wt% of animal leather powder having an average particle size of 250 μm or less and 90 to 40 wt% of a thermoplastic resin having a moldable temperature of 200° C. or less. 2. The leather powder-containing resin composition according to claim 1, wherein the thermoplastic resin having a moldable temperature of 200° C. or lower is linear low-density polyethylene or polyurethane. 3. 20% of the leather powder-containing resin composition according to claim 1 or 2.
Leather-like molded products formed at temperatures below 0℃. 4. The weight loss when extracted with room temperature water for 10 minutes is 5wt.
A leather powder-containing resin composition consisting of 10 to 60 wt% of animal leather powder having an average particle diameter of 250 μm or less and 90 to 40 wt% of a thermoplastic resin having a moldable temperature of 200°C or less was kneaded and granulated. A method for producing a leather-like molded product, which is characterized in that the product is subsequently molded at a temperature of 200°C or less. 5. The method for producing a leather-like molded article according to claim 4, wherein the thermoplastic resin having a moldable temperature of 200° C. or lower is linear low-density polyethylene or polyurethane.