JPH02184353A - Production of leather powder - Google Patents

Abstract

PURPOSE:To crush raw leather with high energy efficiency by hydrating natural leather, heating the leather in a pressurized closed pressure vessel, crushing the leather by instantaneously opening and depressurizing the vessel, disintegrating the crushed leather by a crusher and again crushing the disintegrated leather in the pressure vessel. CONSTITUTION:Natural leather is hydrated and heated in the closed vessel for a specified time, and the vessel is simultaneously pressurized. The pressure vessel is then opened and depressurized to crush the leather. The crushed leather is disintegrated by a crusher, and again crushed in the pressure vessel. As a result, raw leather is crushed more easily than before with high energy efficiency, and the initial and running costs are remarkably reduced. In addition, the thermal transformation of the collagen in the leather tissue is controlled by controlling the conditions in the crushing and recrushing, and excellent physical properties can be imparted to the product leather powder.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing natural leather powder.

(Prior art) Conventionally, in order to produce natural leather powder, the raw material leather is first cut into small pieces, soaked in water for a long time to swell, then dismantled into fibers, dried, and then crushed. The pieces were steamed with heated steam, thoroughly dried, and then processed through a pulverizer.

(Problem to be solved by the invention) However, when natural leather is crushed using the conventional method, it curls,
When making synthetic leather, there was a problem in mixing it with resin etc. because long fibers were formed and the leather powder particles became entangled with each other. As a way to compensate for this drawback, for example,
A method of cutting with a cutter blade with a sharp edge, adding water, crushing it with a crusher until it becomes fibrous, drying it, and then crushing it with a fine crusher (Special Publication No. 57-197
Publication No. 08).

In addition, from the viewpoint that the natural leather powder obtained by fine pulverization should be made into granules rather than fibers, raw leather is pre-processed in a cutting machine or a crusher to form fine pieces, granules, or fluffy leather material. There is a method (Japanese Unexamined Patent Application Publication No. 156552/1983) in which, after steaming with heated steam, it is forcibly dried until the moisture content becomes 4% or less and then crushed.

However, in either method, the raw material leather must be cut into small pieces in advance, which requires a crusher such as a cutter or cutter mill, and energy for its operation. For example, when using a cutter mill with a required power of 37 kW, it will depend on the moisture content of the raw material and the product size.
It was only possible to process about 600 kg/hr (using dry powder).

(Means for Solving the Problems) The characteristic means of the present invention is to put hydrated natural leather in a sealed pressure vessel, heat it for a certain period of time and pressurize it at the same time, and then instantly open the pressure vessel to reduce the pressure. The leather is swollen by causing the leather to be swollen, then crushed in a crusher, and the crushed area is further placed in the pressure vessel and crushed. In other words, when leather containing a large amount of moisture is placed under high temperature and high pressure conditions, rough or weak areas within the leather fiber structure are strongly expanded, causing the fibers to become untangled or crushed in whole or in part. Ru. Therefore, it can be easily coarsely pulverized by directly applying it to an impact pulverizer such as a hammer mill.

Next, this crushed field is placed in a pressure vessel and finely crushed in the same manner as described above to produce natural leather powder. Its action is as follows.

(Function) First, the raw leather is cut into pieces that can fit 19 people in a container, and is brought into contact with steam for a certain period of time in a closed pressure container.Then, the container is instantly released to rapidly reduce the pressure inside the container. In this way, the 4H parts or weak parts within the raw leather fiber structure will have a strong swelling effect, and the fibers will be completely or partially untangled. Therefore, if this is applied to an impact crusher such as a hammer mill, it can be effectively crushed by 1'ft. More specifically, when a piece of natural leather moistened with water is placed in a sealed pressure vessel and heated above the vaporization temperature of water, the water inside the piece of leather is heated and some of it turns into steam, but most of it turns into steam. Since the inside of the container is under pressure, the water stays in the raw leather as pressurized hot water, and together with the steam, it swells the raw leather, especially the phased parts of the leather fibers, and loosens the entanglements of the Kolaken fibers in the leather tissue. When the high-temperature, high-pressure container is instantly released and the pressure is rapidly reduced, the hot water inside the raw leather vaporizes and expands due to the sudden pressure change, causing the pre-unraveled leather fibers to explode from within. It is crushed or cut by the rapid swelling action as shown in the figure. The crushed natural leather obtained in this way has strain applied to the inside of its structure, so it can be crushed without drying using an HS-type grain crusher such as a hammer mill. It can be done.

In order to further pulverize this crushed pulverization, the entire amount,
Alternatively, to prevent excessive gelatinization, sieve into appropriate sizes, put only the coarse grains into a sealed pressure vessel, and crush the leather again under the same or different conditions as before. . The extracted crushed product is further dried and subjected to a pulverization process using a pulverizer to produce fine natural leather powder.

According to such means, the raw material leather can be crushed in a shorter time, more effectively, and with better energy efficiency than conventional methods.

(Effects of the Invention) As described above, according to the present invention, raw material leather can be crushed much more easily and with more energy efficiency than conventional products, and initial costs and running costs can be significantly reduced. In addition, by adjusting the operating conditions during crushing and re-crushing, it is possible to adjust the thermal change state of the Kolaken protein in the leather tissue and give good physical properties to the product leather powder. However, the natural leather powder is distributed in a uniformly dispersed state without agglomeration, and the amount of natural leather powder can be increased in terms of capacity, so it has the texture of natural leather, excellent moisture absorption and desorption properties, and non-static properties. and water resistance,
In fact, it has become possible to produce large amounts of natural leather powder at a sufficiently low cost that is suitable for producing high-quality artificial leather that has properties superior to natural leather in terms of durability and antibacterial properties. Ta. In addition, by secondary crushing the shredded and crushed leather raw materials into fine powder and coarse particles separately under appropriate conditions, there is a disadvantage that the Kolaken protein deteriorates due to the strong influence of temperature. This eliminates the need for raw materials and converts the entire raw material into natural leather powder suitable for the intended use, contributing to resource conservation.

(Example,]) Next, examples will be shown.

The cutting waste generated during shoe manufacturing was added with water to make the moisture content 61%, and then put into a pressure vessel with a heating jacket.
g, 4/cni of steam was simultaneously supplied into the vessel and into the jacket, and after heating the raw material for about 18 minutes, the outlet of the pressure vessel was opened all at once to crush it. Part of the water was separated from this crushed skin waste, and the water content was about 40%. After crushing this crushed raw material leather waste using a hammer mill,
The mixture was put into the pressure vessel again, and 2.8 kg/crn of steam was supplied in the same manner as above, and the mixture was heated under pressure for about 8 minutes. Next, the outlet of the pressure vessel is opened all at once and crushed again, and further dried until the water content is reduced to around 5%.Then, it is crushed with an impact crusher to form fine natural leather powder with an average particle size of 20μm. was able to manufacture.

(Example 2) The same raw materials as Example 1 were added with water to make the moisture content 60%,
Pour the heated shaker into a pressure vessel with 1 tsp.
kg/cni of steam was supplied into the container and the jacket at the same time to heat the raw material for about 18 minutes, and then the outlet of the pressure vessel was opened all at once to crush it. This crushed raw material leather waste was crushed in a hammer mill as it was (7) and then sieved with 10 meshes using a sieve machine, resulting in approximately 30%
was recovered as fine particles. Furthermore, only the coarse particles were put into the pressure vessel again, and 2.8 kg/cm of steam was released into the pressure vessel.
were supplied in the same manner as above and heated under pressure. Next, the outlet of the pressure vessel is opened all at once and crushed again, and then sieved and removed together with the removed fine particles, dried until the moisture content is around 5%, and then crushed with an impact crusher. However, natural leather fine powder equivalent to Example 1 could be produced.

that's all Applicant: Hosokawa Micron Co., Ltd. 8)

Claims (1)

[Claims] After adding water to natural leather and heating and simultaneously pressurizing it in a sealed container for a predetermined period of time, the pressure container is momentarily opened to reduce the pressure to crush the leather, and the crushed leather is passed through a crusher. A method for producing leather powder, which comprises crushing and then crushing again in the pressure vessel.