JPS63152485A - Leather-like molding - Google Patents

Abstract

PURPOSE:To obtain a leather-like molding having characteristics of a natural leather, by blending a thermoplastic resin compound containing a synthetic rubber elastic raw material with a granular gelatin, heat molding the blend and removing the surface skin layer of the resultant molding from the molding and retaining water content in the above-mentioned gelatin at the same time. CONSTITUTION:A thermoplastic resin compound containing a synthetic rubber elastic raw material such as butadiene based synthetic rubber, for example, 70-95wt% is blended with powdery gelatin, 5-30wt% and the blend is heat molded. At least part of the surface skin layer of the resultant molding is removed from the molding and the above-mentioned powdery gelatin is exposed on the surface of the molding and normally about 16% water content is contained to the gelatin in order to create the same environment as that existing in a living body as a biopolymer to provide the aimed leather-like molding close to characteristics of natural leather. The molding is flexible and have excellent viscoelasticity, great impact-adsorbing effect as well as excellent cold resistance.

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. By bringing these gelatin particles into a swollen state similar to the situation in which they are actually used as biopolymers, we aim to change the properties of the molded product and also change the surface of the molded product so that the gelatin particles are exposed on the surface of the molded product. The present invention provides a leather-like molded product from which the skin layer has been removed.

(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, natural leather materials that heat up have a limited supply, are susceptible to brittleness due to swelling, rot, mildew, and discoloration, and are always subject to shape constraints.

Therefore, in recent years, improvements have been made to synthetic leather or artificial leather that has the characteristics inherent to leather, such as polyamide-based, polyurethane-based, polyamino acid-based synthetic leather, or special lotus root type hollow H & fibers or fine fiber bundle type #ll fibers. Artificial leather and the like made of a porous structure of fiber entanglement and a binder mainly composed of polyurethane elastomer have come to be supplied.

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. 81-102813 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 materials, it is technically difficult to make fine granular powder that is not fibrous due to the fact that 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. They exist as mutually intertwined lumps, and this was thought to be the cause of pulsations in the molded resin during extrusion molding.

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 that of oblique epithelial leather powder.
As a substitute for oblique epithelial leather powder, we were able to obtain better-than-expected effects.

(Object and structure of the present invention) The leather-like molded product according to the present invention relates to an improvement on the conventional technology in the case of diagonal molding, and focuses on gelatin, which is easier to mold than leather powder and can be mass-produced at a lower cost. However, by incorporating gelatin, it is intended to be used in place of or in conjunction with leather powder, and at least to derive functional characteristics that are the same 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 purpose of dipping, first granules the gelatin to be mixed so that it is evenly mixed with the synthetic resin material, and then mixes it evenly with the 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. These gelatin particles usually contain about 16% water to create an environment similar to that existing in living organisms as biopolymers, and then the gelatin particles are exposed to the surface of the molded product. The skin layer on the surface of the molded product was removed.

(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 a diagonal 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. Therefore, uneven distribution 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. By 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) In cases where the gelatin particles in these molded articles are in contact with each other, since the surface skin layer of the molded article has been removed, these gelatin particles themselves may swell or dry in sequence. -, and it was recognized that humidity could be adjusted through the molded product.

(7) Since the gelatin particles in the 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 that it prevents a sticky feeling upon contact and has 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 l 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.

Plasticizers, stabilizers, fillers, lubricants, pigments or dyes, blowing agents, and mold release agents commonly used in resin molding are added to the above resin 1 and gelatin 2, and then a resin compound 70~ The ratio of gelatin to 95% is 5 to 30% (the blending ratio is not necessarily limited to this).

For example, PVcloo, DOP90, ZN-BA by weight
3. Gelatin 30) as calender roll, extrusion,
Moldings were obtained by injection or other methods.

The visible molded product has a skin layer a on its surface,
The gelatin 2 is separated from the outside world by this skin layer a. Therefore, this skin ia is removed by an appropriate method such as sanding, shot blasting, or slicing with a cutter.

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.

Further, the surface of the molded product is subjected to leather graining, sanding to give it a suede look, various surface decorations such as enamel finishing, and other finishing touches.

The gelatin 2 in the molded article constructed as described above became hydrated and swollen before and after its air-dried moisture content, giving the molded article a unique function.

(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) Because the gelatin particles on the surface functioned as a carrier, coloring and surface coating were easier, and the gloss and color tone were good.

(5) Since the gelatin particles on the surface functioned as a carrier, the adhesive properties were good and the adhesive process was easy.

(6) Since the frictional resistance of the gelatin particles on the surface is large, slipping does not occur 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]

FIG. 1 is an enlarged sectional view of a main part of a molded article according to the present invention, and FIG. 2 is an enlarged sectional view of a molded article with a skin layer a removed. 1...resin, 2...gelatin.

Claims (1)

[Claims] Granular gelatin is mixed with a thermoplastic resin compound containing a synthetic rubber elastic material and heated and molded, and at least a part of the surface skin layer of the molded product is removed, and the gelatin in the molded product is freed from moisture. A leather-like molded product characterized by containing: