JPS63152480A - Leather-like molded article - Google Patents

Abstract

PURPOSE:To obtain a leather-like molded article close to natural leather showing functions as a biopolymer, by blending a thermoplastic resin containing an elastic material of synthetic rubber with powdery gelatin, molding under heating and making the gelatin in the molded article have a fixed water content. CONSTITUTION:A resin (e.g. 70-95wt%) 1 consisting of a elastic material of synthetic rubber such as butadiene rubber, etc., and a thermoplastic resin (e.g. vinyl chloride resin, etc.) is blended with granular gelatin 2 (e.g. 5-30 weight ratio) having about 1mum particle diameter and molded into a sheetlike shape by calendering rolls, etc. The gelatin particles in the molded article have usually about 16% water content to give a leather-like molded article making the same environment as that existing in organism as a biopolymer, having no feeling of greasiness in contact with skin and showing feeling and function close to natural leather.

Description

Detailed Description of the Invention (Field of Industrial Application) This invention incorporates gelatin as a biopolymer containing various amino acids such as glycine, proline, and hydroxyproline, as well as ash and moisture into a synthetic resin molding, It is intended to make the synthetic resin molded product have properties similar to natural leather, and more specifically, the gelatin mixed in the synthetic resin is made into granules and is dispersed evenly. In addition, the present invention provides a leather-like molded article in which the properties of the molded article can be changed by bringing these gelatin particles into a swelling state similar to the situation in which they are actually used as biopolymers.

(Prior art) Leather has been used as a material closely related to daily life since ancient times, and due to the properties of the unique collagen fiber bundles of leather fabric, it has moisture absorption, heat resistance, and cold resistance properties, and can be used as a strong fabric material. Ta.

However, such natural leather materials have a limited supply, are at risk of becoming brittle due to swelling, rotting, molding, and discoloration, and are always subject to constraints in terms of shape.

Therefore, in recent years, improvements have been made to synthetic leather or artificial leather that has the characteristics inherent to leather, such as polyamide, polyurethane, or polyamino acid synthetic leather, or three-dimensional fiber entanglement of special lotus root type hollow fibers or fine fiber bundle type fibers. Artificial leather and the like are now being supplied, which are made of a porous structure of a binder made mainly of polyurethane elastomer.

However, all of these methods attempt to create water absorption, permeability, or elasticity through reticulation or porosity using synthetic resin materials that do not swell, and are different from natural leather based on biopolymers. It was considered difficult to develop similar properties.

(Problems to be Solved by the Invention) As a method of using leather materials as they are, these leather materials are broken and beaten into short fibers, and these short fibers of leather material are pressed into a felt shape. Felt materials, filter vortex materials, and vibrating fabric materials for speakers have been developed for some time. However, the present applicant was the first to develop industrially the development of pulverizing or cutting leather material into a powder form and using this powdered leather material to produce leather fabric, and patent application No. 102,813/1984, etc. Many inventions have been disclosed.

By the way, when such leather material is pulverized and mixed with resin and molded, it has been found that the finer the leather powder, the better the characteristics of the molded leather-like fabric, and the easier it is to blend with the resin. did.

However, when pulverizing leather material, it is technically difficult to make powder that is not fibrous and has a particle size because the leather material is collagenous. When the particle size is above or below the particle size, there is a problem in that the leather powder becomes entangled with each other in a cotton-like manner.

In particular, the leather material is crushed by a crusher or ultrafine crusher, etc.
When made into a uniform fine powder of about 0 mesh, the fine powder becomes intertwined with each other and takes on a cotton-like appearance, and does not mix properly with the synthetic resin material. It exists as a tangled mass, and this was considered to be the cause of pulsation in the molded resin during extrusion molding and the like.

In addition, if the leather material becomes a certain lump like this, a molded product will be obtained in which the resin material and the leather material are separated, and of course the strength of the molded product will be extremely poor. However, there was an inconvenience in that the molded product did not have any of the characteristics of the leather material to which it was mixed.

Based on the above points, the applicant attempted various improvements regarding the inclusion of gelatin, which is a biopolymer similar to epithelial leather powder, and
As a substitute for epithelial leather powder, we were able to obtain better-than-expected effects.

(Objects and Structure of the Present Invention) The leather-like molded product according to the present invention is an improvement on the prior art described above, and focuses on gelatin, which is easier to mold than leather powder and can be mass-produced at a lower cost. By incorporating this gelatin, it is intended to be used in place of or together with leather powder, and it is an attempt to derive functional characteristics that are at least the same as or better than those of molded products using leather powder.

The leather-like molded product according to the present invention, as a means of achieving the above-mentioned purpose, first pulverizes the gelatin to be mixed in so that it is evenly mixed with the synthetic resin material, and then transforms it into a synthetic rubber elastic material. Heat molded with a thermoplastic resin containing. As a result, the mixed gelatin was dispersed in the molded article in the form of extremely fine particles, and a portion of the mixed gelatin was configured to be in continuous contact with the molded article. Molded articles were obtained by making these gelatin particles contain water, usually about 16%, to create an environment similar to that existing in living organisms as biopolymers.

(Functions and Effects) It has been confirmed that the leather-like molded article according to the present invention has the following functions and effects because it has the above structure.

(1) Gelatin has the property of becoming brittle when it is released from its swollen state and dried, so it can be easily made into fine particles. I was able to create it.

(2) When mixed into thermoplastic resins containing synthetic rubber elastic materials, gelatin has a unique slipperiness similar to talc, so it has the ability to mix evenly into these resin materials. The maldistribution of gelatin particles that would otherwise be present in the molded product was avoided.

(3) The mixed gelatin easily becomes a sol during heat treatment during molding, making resin molding easier by increasing the fluidity of the entire molded resin. It has the advantage of not causing distortion, and as a result, molding distortion of the molded product is prevented.

(4) The gelatin particles that are evenly scattered throughout the molded product exhibit high viscoelasticity as they gel, creating a net-like viscoelastic structure in the molded product and a net-like synthetic resin that incorporates this structure. As a result of creating an aggregate structure, high values were shown for bending fracture strength, shock absorption properties, etc.

(5) Since the gelatin particles in the molded product are in a swollen and viscous state similar to that of ordinary biopolymers, the molded product always exhibits a constant moisture content, especially close to that of human skin, and its thermal conductivity. Its heat retention and contact resistance values are close to those of the skin, making it particularly suitable for use in areas that come into contact with humans.

(6) When the gelatin particles in these molded products are in contact with each other, these gelatin particles themselves are sequentially swollen or dried, and it is recognized that humidity can be adjusted through the molded product. It was done.

(7) When gelatin particles in a molded product are exposed on the surface of the molded product, these gelatin particles on the surface directly absorb moisture, swell, and have the function of sequentially sending the absorbed moisture deep into the molded product. It has the characteristics of preventing a sticky feeling upon contact and having the same resistance as human skin.

(8) Particulate gelatin is evenly dispersed in the molded product, and these particles contain a predetermined amount of water and are in a swollen state, which prevents static electricity inherent in synthetic resins and reduces static electricity. It is said to be effective for use in areas where static electricity is likely to be generated, or for use in various electrical equipment where generation of static electricity is averse.

(Example) Hereinafter, a typical example of the leather-like molded article according to the present invention will be described.

First, the synthetic resin 1 used as the base material is butadiene-based synthetic rubber,
Synthetic rubber elastic materials such as olefin synthetic rubber, polysulfide rubber, fluorine comb, polyurethane rubber, colorosulfonated polyethylene, silicon rubber, and chloride rubber, and heat-resistant materials such as vinyl chloride, vinyl acetate, ABS, polycarbonate, polyethylene, and polystyrene. It is used selectively from plastic resins, etc.

The gelatin 2 that is then mixed in typically has an average molecular weight of 200.
It is a derived protein with a molecular weight of 0.00 to 150,000, and is gelled by drying to a water content of nearly 16%, and crushed in this hardened state to form colored or non-colored fine particles. As much as possible, the particle size of gelatin 2 was adjusted to about 1ILm so that the following kneading, molding, and various functions in the molded product could be effectively achieved.

A resin compound containing 70 to 95% of the above resin 1 and gelatin 2 with the addition of plasticizers, stabilizers, fillers, lubricants, pigments or dyes, blowing agents, and mold release agents commonly used in resin molding. and gelatin at a ratio of 5 to 30% (the blending ratio is not necessarily limited to this. For example, PVCloo, DOP90.ZN-BA3,
A molded product was obtained using calender roll, extrusion, injection or other methods.

The film and sheet-like molded products were mainly soft or semi-hard, and the injection molded products were mainly hard or semi-hard.

Furthermore, by laminating cloth or paper as a reinforcing material to film and sheet-like molded products, their tear strength can be increased or distortion can be prevented.

In addition, the surface of the molded product is subjected to leather texture processing, sanded to give it a suede look, and various surface decorations such as enamelization and other finishes are applied.

The gelatin 2 in the molded article constructed as described above was brought into a hydrated and swollen state before and after its air-dried moisture content, providing a unique function to the molded article.

(1) It exhibits remarkable viscoelasticity for molded products that do not contain gelatin, provides a soft feel, and has a large impact absorption effect.

(2) It has good hygroscopicity and prevents dust from adhering to it due to static electricity.

(3) Distortion in the resin was absorbed by the presence of gelatin particles, preventing distortion over time after molding, effectively preventing deterioration, and providing good oil resistance.

(4) Since gelatin particles serve as a carrier, coloring and surface coating treatments are easier, and the gloss and color tone are good.

(5) Since the gelatin particles serve as a carrier, adhesiveness is better and adhesive processing is easier.

(6) Gelatin particles have high frictional resistance, so they do not slip even on wet or frozen surfaces.

(7) Since the gelatin particles are incorporated into the molded product as a unique structure, a significant vibration damping effect is produced.

(8) The inclusion of gelatin particles provides good cold resistance, and the molded product does not tear or crack even in cold weather.

[Brief explanation of the drawing]

The old and old drawings are enlarged sectional views of essential parts of the molded product according to the present invention. 1...resin, 2...gelatin.

Claims (1)

[Claims] 1. A leather-like molded product, characterized in that granular gelatin is mixed with a thermoplastic resin containing a synthetic rubber elastic material and then heated and molded, and the gelatin in the molded product contains water.