JP2006241314A - Natural leather product processing material and natural leather product imparted with water repellency, and method for producing the natural leather product processing material or natural leather product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a natural leather product processed with natural leather such as mammals, birds, reptiles, etc., a material for processing natural leather product for processing such natural leather product, and a method for producing these materials, water repellency Natural leather products that can be used for processing natural leather products and natural leather products that have been provided with natural water, can maintain the water-repellent function for a long period of time without degrading the properties of the natural leather materials and the quality of the leather products. It is an object of the present invention to provide a product, a material for processing a natural leather product, and a manufacturing method thereof.
A water-repellent component is infiltrated into natural leather tissues and fibers using a high-pressure fluid as a medium.
[Selection] Figure 1

Description

  The present invention is a natural leather product processed with natural leather such as mammals, birds, reptiles, and the like, and a natural leather product processing material for processing such natural leather product. The present invention relates to a leather product processing material, a natural leather product, and a method for manufacturing these natural leather product processing material or natural leather product.

  Natural leather collected from mammals such as sheep, deer, cattle, and pigs, and reptiles such as crocodiles, lizards, and snakes, has a texture and material properties such as texture and flexibility compared to synthetic leather. It is excellent and used in various leather products such as leather and fur. However, products such as gloves, wallets, bags, and shoes manufactured using natural leather have a high-class feeling due to their unique texture, while water resistance is inferior to products manufactured using synthetic leather. There is a nature.

  In view of such properties, attempts have been made to perform water-repellent processing in order to impart durability as a product. Examples of such methods include a method of directly applying a water-repellent agent, and a method of applying a water-repellent agent. A method of spray coating by dissolving in a solvent is described in, for example, [0003], which is a prior art of Patent Document 1 below.

  However, these methods merely attach the water repellent component to the surface of the natural leather material, and the effect of water repellency is temporary. There is a problem that the effect is not sustainable as described. In other words, the surface of leather products such as gloves, wallets, bags, and shoes is often exposed to harsh conditions such as bending, pulling, and colliding with foreign materials. It becomes easy to detach from the material.

  Even in the case of synthetic leather, it is recognized that such a problem of sustainability of the effect can occur in the same way, but in reality, water repellent processing such as the above-mentioned application, spray coating, etc. is performed. As a method, an application such as the following Patent Document 2 has been filed, and as a method by spray coating, an application such as the following Patent Document 3 has been filed.

  On the other hand, in the case of natural leather, there are almost no patent applications for water-repellent finishing by coating, spray coating, or the like. This is thought to be due to the characteristics of natural leather. That is, when the water repellent is detached after performing the water repellent process by the above application, spray coating or the like, moisture easily penetrates into the leather material from the detached surface. For this reason, various deteriorations such as curing due to moisture, generation of mold, and discoloration occur.

  Furthermore, when the water repellent component is directly adhered by application or spray coating, the leather material loses air permeability because the component concentrates and adheres to the leather surface. Further, a volatile organic solvent or the like is used when performing the water-repellent processing, but this organic solvent deteriorates the natural leather, so that the durability of the processed leather product is lowered. Therefore, by losing the excellent physical properties of the natural leather material, the quality as a leather product is impaired, and the product value is significantly impaired.

  A description to support this is also made in [0003] of Patent Document 1. In other words, “Pretreatment with water repellent and spray coating makes it impossible to finish natural leather afterwards, and in fact, natural leather is subjected to water repellency and then enameled and finished. It hasn't been done. " Therefore, if water-repellent treatment is performed on natural leather, a consumer who has purchased a product purchases a special water-repellent agent and applies it. However, as described above, the effect is not sustainable in such treatment.

  In the case of natural leather, an attempt has been made to perform water-repellent treatment in a process such as “tanning”, which is a process for producing a sheet material for processing for processing natural leather products. The invention described in Patent Document 1 is one such technique, and [0006] includes a mixture of a predetermined amount of anion and vinyl polymer in the step of removing acid from leather and the retanning step. A method of processing using the method is disclosed. However, skill is required to perform the above-described processing in a process unique to natural leather, and it is not necessarily a general processing method.

JP 2000-119700 A JP 7-305280 A JP 2003-154307 A

  The present invention has been made in order to solve the above-described problems, and does not deteriorate the physical properties of leather materials and the quality of leather products, and can maintain the water-repellent function for a long period of time. It is an object to provide a natural leather product, a material for processing a natural leather product, and a method for producing them.

  In order to solve such problems, the present invention has been made as a natural leather product processing material and a natural leather product, and a natural leather product processing material and a method for producing a natural leather product. The invention according to claim 1 relating to a material for use is characterized in that a water-repellent component is infiltrated into a tissue or fiber of natural leather using a high-pressure fluid as a medium.

  The invention according to claim 2 is characterized in that, in the natural leather product processing material according to claim 1, the water repellent component is one or more of fluororesin, silicone resin and fluorosilicone resin. And Furthermore, the invention according to claim 3 is the material for processing a natural leather product according to claim 1 or 2, characterized in that the natural leather is mammalian leather or fur, bird fur, or reptile leather. .

  Examples of mammals used as leather include sheep, deer, cows and pigs, and examples of mammals used as fur include mink, chinchilla, mole and fox. In addition, the present invention can be applied to products distributed as fur leather products overseas such as weasel, camel, kangaroo, reindeer, elk and the like. Furthermore, the present invention can also be suitably applied to leather of reptiles such as crocodiles, lizards and snakes.

  Furthermore, the invention according to claim 4 relating to a natural leather product is characterized by comprising the natural leather product processing material according to any one of claims 1 to 3. Furthermore, the invention according to claim 5 is characterized in that a water-repellent component is infiltrated into a tissue or fiber of natural leather using a high-pressure fluid as a medium.

  Furthermore, the invention according to claim 6 relating to a method for producing a raw material for processing natural leather products is characterized in that a water-repellent component is permeated into the tissues and fibers of natural leather using a high-pressure fluid as a medium. Further, the invention according to claim 7 is the method for producing a raw material for processing natural leather product according to claim 6, wherein the water repellent component is allowed to penetrate into the natural leather tissue or fiber before the water repellent component penetrates into the natural leather tissue or fiber. It is characterized by removing impurities such as residual lipid and moisture.

Furthermore, the invention described in claim 8 is characterized in that in the method for manufacturing a natural leather product processing material described in claim 7, impurities are removed using a high-pressure fluid. The invention according to claim 9 is the method for producing a material for processing a natural leather product according to any one of claims 6 to 8, wherein the medium is a mixture of a high-pressure fluid and a solvent that dissolves the water-repellent component. It is characterized by.
Furthermore, the invention according to claim 10 is the method for producing a material for processing natural leather products according to claim 9, wherein the solvent for dissolving the water-repellent component is one or two of petroleum hydrocarbons and fluorine hydrocarbons. It is characterized by being.

  As the high-pressure fluid, fluids at various pressures can be used, but it is preferable to use a supercritical fluid or a subcritical fluid that has excellent permeability to the leather material. Moreover, it is preferable that the kind of fluid is a thing which has high solubility of a water-repellent component as a pouring medium for penetrating a water-repellent component to the inside of a natural leather material, and does not deteriorate a natural leather material. For example, carbon dioxide, nitrous oxide, trifluoromethane, or a mixture of two or more thereof can be used. Further, as the petroleum hydrocarbon, it is preferable to use a nonpolar hydrocarbon solvent such as normal hexane, normal heptane, isomers of heptane, normal octane, isooctane and the like. Further, as the fluorinated hydrocarbon, it is preferable to use, for example, a fluorine-based inert liquid manufactured by 3M, Fluorinert (trade name), Novec HFE (trade name), or the like.

  Furthermore, in the present invention, the material for processing natural leather products is a material after performing so-called pretreatment such as “tanning”, and is formed into a natural leather product having a desired shape, before being processed into a sheet shape, etc. It means the processing material formed in the above.

  As described above, in the present invention, the water-repellent component is infiltrated into the tissue and fibers of natural leather using a high-pressure fluid as a medium, so that it is simply applied to the surface of the leather material as in the conventional coating method and spray coating method. Compared to the method in which the components are simply attached, the water repellent function is significantly improved.

  In addition, since the high-pressure fluid as described above is infiltrated as a medium, it does not impair the properties of the leather, especially for natural leather materials whose properties have been significantly impaired by the conventional method of directly attaching active ingredients. There is an effect that the properties inherent to natural leather such as durability, durability, water absorption, and dissipation are not impaired.

  As a result, it is possible to provide a leather product which is imparted with water repellency and which does not impair the properties of leather, particularly the natural properties of natural leather. In particular, when a sheep leather material is used for gloves used under harsh conditions, there is an actual advantage that it is possible to manufacture a product having a higher water repellency than other animal leather materials.

  Furthermore, after the component is once applied between the fibers of the leather material, the component is not carelessly detached, so that the water repellent effect can be maintained for a long time.

  Furthermore, since the water-repellent component penetrates deep into the leather material structure and fibers, even in the case of leather products with the silver surface as the surface side, the silver surface is the back surface side (ie, the mid-floor surface is the surface). Even a so-called back skin product is effective in providing a leather product that can retain the water-repellent component for a long period of time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1: shows the schematic block diagram of the apparatus used for manufacture of the raw material for natural leather goods processing which provided the water repellent component as one Embodiment. As shown in FIG. 1, the apparatus used in the method for manufacturing a material for processing natural leather products according to this embodiment includes a high pressure cell 1, a cylinder 4, a high pressure pump 5, a pressure gauge 6, and a back pressure valve 7. It has.

  The high pressure cell 1 is for containing a leather product processing sheet, which is a material for processing natural leather products, and a water repellent component, and the water repellent component penetrates into the leather product processing sheet in the high pressure cell 1. It will be. The high-pressure cell 1 is made of a pressure-resistant stainless steel and is composed of a cell body 2 and a lid 3. The cylinder 4 is for storing a high-pressure fluid, and carbon dioxide is used as the type of fluid. The high pressure pump 5 is a pump for supplying the fluid in the cylinder 4 to the high pressure cell 1, and the pressure of the high pressure pump 5 is measured by the pressure gauge 6.

  The back pressure valve 7 can be opened and closed with a predetermined pressure, and the operation pressure can be kept constant at a predetermined value. Furthermore, by opening the back pressure valve 7 and reducing the pressure, the supercritical fluid is decompressed and separated from the high pressure cell 1. In addition, the natural leather product processing material manufacturing apparatus of the present embodiment includes a piping portion (shown in a diagram).

  Next, an embodiment of a method for producing a natural leather product processing material imparted with a water repellent component using such an apparatus will be described.

  First, a processing sheet 8, which is a material for processing natural leather products, is installed in the high-pressure cell 1, and a water-repellent component is charged into the high-pressure cell 1. In this embodiment, a cowhide material is used as the natural leather product processing material. This cowhide material is obtained by subjecting the raw material to a pretreatment for manufacturing a leather material such as tanning.

  That is, the cow skin part 9 (outside the meat part 15), which is a raw material, has a structure composed of a silver layer 11, a middle floor 13, and a floor 14 having a silver surface 10 on the surface as shown in FIG. As shown in FIG. 3, the above-mentioned pretreatment is performed on a state in which the silver layer 11 is peeled off and the nubuck 12 is exposed on the surface (which is of course peeled off from the meat portion 15). What was formed in the sheet form is used as the processing sheet 8 in this embodiment.

  Next, a thermostatic chamber (not shown) that accommodates the high-pressure cell 1 is set to a target temperature, and the release pressure of the back pressure valve 7 is set to a target pressure. To supply high-pressure cell 1 with carbon dioxide.

  Carbon dioxide becomes a supercritical fluid under conditions of a temperature of 31.1 ° C. (critical temperature) or higher and a pressure of 73 atm (critical pressure) or higher, and the temperature setting of the thermostatic chamber and the pressure at the back pressure valve 7 as described above. The supercritical state can be maintained by setting.

  After the temperature and pressure in the high-pressure cell 1 reach predetermined values, carbon dioxide is circulated for a predetermined time. At this time, the extraction power of supercritical carbon dioxide extracts and removes impurities such as fats and oils and moisture remaining in the structure of the leather product processing sheet and the gaps between the fibers, and attaches the water repellent component to be applied A sufficient space can be secured.

  After the removal of impurities is completed, the back pressure valve 7 is opened, carbon dioxide in the high pressure cell 1 is removed, the high pressure cell 1 is opened, and an additional raw material containing an active ingredient such as a water repellent component is additionally charged. . Subsequently, the inside of the high-pressure cell 1 is set again at a predetermined temperature and pressure, and left for a predetermined time. As a result, the water repellent component penetrates into the structure of the leather material and the gap between the fibers and is applied to the processing sheet 8.

  This will be described in more detail. First, the water-repellent component is extracted by supercritical carbon dioxide, and then the mixed fluid of the supercritical carbon dioxide and the water-repellent component penetrates between the leather material tissue and the fibers. The cow skin 9 which is the raw material of the processing sheet 8 has a unique tissue structure composed of the silver layer 11, the middle floor 13, and the floor 14 as described above. Difficult to penetrate inside. However, in this embodiment, a water-repellent component can be imparted to the deep part of the gap between the tissues and fibers by using a supercritical fluid having a penetrating power for details as a medium.

  Furthermore, not only cowhide but natural leather has fine gaps between fibers, so once the water-repellent component has adhered, the water-repellent component is not inadvertently detached, and the water-repellent function is maintained over a long period of time. be able to. In addition, although lipid is contained between the fibers of cowhide, since carbon dioxide is used as the supercritical fluid in this embodiment, the solubility between the lipids of supercritical carbon dioxide and the extraction power can be changed between the fibers of cowhide. The lipid present in the water is suitably removed.

  Subsequently, when the back pressure valve 5 is released, the flow path is depressurized, the supercritical carbon dioxide returns to a gaseous state due to the pressure drop, and the supercritical carbon dioxide is naturally diffused and removed from the leather material. On the other hand, the water repellent component is adsorbed and trapped in the leather tissue and fibers and remains in the leather material.

  In this way, a processing sheet in which the water-repellent component has permeated into the interior together with the surface is produced. As described above, carbon dioxide is a temperature of 31.1 ° C. (critical temperature) or higher, 73 atm (critical). Since it becomes a supercritical fluid under the conditions of the above pressure), the temperature can be set to a relatively low temperature, and the processing sheet and the water repellent component can be prevented from being deteriorated by heat.

(Embodiment 2)
In the manufacturing apparatus for raw materials for processing natural leather products according to the present embodiment, in addition to the high pressure cell 1, the cylinder 4, the high pressure pump 5, the pressure gauge 6, and the back pressure valve 7 of the first embodiment, as shown in FIG. A pump 16 and a water repellent component container 19 are provided.

  In the first embodiment, the water-repellent component is directly stored in the high-pressure cell 1. In the present embodiment, the water-repellent component is stored in the water-repellent component storage container 19. I tried to supply.

  More specifically, first, the valves 17 and 18 in the circulation flow path are closed, and the valve 20 is opened, so that carbon dioxide is supplied from the cylinder 4 to the high pressure cell 1 as in the first embodiment. . If the temperature and pressure in the high-pressure cell 1 reach predetermined values as in the first embodiment and then left for a predetermined time, supercritical carbon dioxide will permeate between the leather tissue and fibers, and the cow leather tissue and fibers Is preferably removed.

  Next, the valve 20 on the carbon dioxide supply side is closed, the back pressure valve 7 is opened to release carbon dioxide in the high pressure cell 1, and then a system is used from the back pressure valve 7 using a vacuum pump (not shown) or the like. The inside is evacuated. Subsequently, the water repellent component is injected into the high-pressure cell 1 by opening the valves 17 and 18 in the circulation channel and the valve 21 on the water repellent component supply side.

  Subsequently, after the valve 20 is opened and carbon dioxide is again flowed into the high pressure cell 1 and set to a predetermined temperature and pressure, the supply-side valves 20 and 21 and the back pressure valve 7 are closed, The valves 17 and 18 are opened and the circulation pump 16 is operated. As a result, the water-repellent component suitably permeates between the tissues and fibers of cowhide from which lipid has already been removed.

  Also in this embodiment, since a supercritical fluid having a penetrating power to details is used as a medium, a water-repellent component can be imparted to the deep part of the gap between the tissues and fibers, and the water-repellent component is once imparted. After that, inadvertent detachment of the water repellent component can be suitably prevented.

(Embodiment 3)
In this embodiment, a water-repellent component was applied using sheep leather instead of the cowhide of Embodiment 1 or 2 as a raw material for processing natural leather products. As the apparatus, the same apparatus as in the first or second embodiment was used.

  Also in this embodiment, since a supercritical fluid having a penetrating power to details is used as a medium, a water-repellent component can be imparted to the deep part of a sheep leather tissue and a gap between fibers. After the is imparted, inadvertent detachment of the water repellent component can be suitably prevented. In addition, since carbon dioxide is used as the supercritical fluid, the lipid existing between the fibers of sheep leather is suitably removed by the dissolving power and extracting power of the supercritical carbon dioxide with respect to the lipid content.

(Embodiment 4)
In this embodiment, a water repellent component was imparted by using deer leather instead of cowhide of Embodiment 1 or 2 and sheep leather of Embodiment 3 as a raw material for processing natural leather products. As the apparatus, the same apparatus as in the first to third embodiments was used.

  Also in this embodiment, since a supercritical fluid having a penetrating power to details is used as a medium, a water repellent component can be imparted to the deep part of the gap between the deer leather structure and fibers, and after imparting, Inadvertent scattering of water repellent components can be suitably prevented, and carbon dioxide is used as the supercritical fluid, so lipids that exist between the fibers of deer leather due to the solubility and extractability of supercritical carbon dioxide in the lipid content. Is preferably removed.

  In this embodiment, the leather structure is fine compared to cowhide and sheep leather, and deer leather with many gaps between fibers is used, so the amount of water repellent that penetrates into the leather can be increased. It is. As a result, it is possible to obtain a processing sheet having a higher water repellent effect.

(Other embodiments)
In each of the above embodiments, supercritical carbon dioxide is used as a medium for imparting various components such as a water repellent component to a raw material for processing natural leather products, but the operation temperature is lower than the critical temperature, or the operation pressure is lower than the critical pressure. However, it is also possible to use so-called subcritical carbon dioxide, which is close thereto. Furthermore, it is possible to use a high-pressure fluid other than the supercritical fluid and the subcritical fluid.
Furthermore, although supercritical carbon dioxide is used in the above embodiment, a high-pressure fluid such as a supercritical fluid other than carbon dioxide or a subcritical fluid may be used.

  Furthermore, in order to increase the extraction effect of various components, it is possible to add petroleum hydrocarbons, fluorine hydrocarbons and the like as auxiliary solvents. In this case, the addition amount of the auxiliary solvent is preferably 1 to 10% with respect to the supercritical fluid. This is because if the added amount of the auxiliary solvent is less than 1%, the solubility of the water repellent in the supercritical fluid is low, and if it exceeds 10%, the leather tissue itself may be deteriorated.

  Furthermore, various water repellents such as a fluororesin, a silicone resin, and a fluorosilicone resin can be used as the type of the water repellent component. Furthermore, the structure of the apparatus to be used is not limited to the above embodiment.

  Furthermore, the applicable leather products include wallets, business card holders, hats, mufflers, shirts, waistcoats, vests, jackets, jumpers, coats, trousers, pants, gloves, shoes, bags, bags, bags, key chains, and cell phone straps. It can be applied to various products such as hanging leather, toys and stationery.

  In addition to leather products, the present invention can also be applied to fur products such as coats, collar wraps, and accessories. Furthermore, in addition to such clothes and decorative items, the present invention can be applied to fur for animal and bird stuffing. When applied to furs, it is natural to use fur that has been processed by leaving hair and feathers without exposing the silver surface.

  Furthermore, the kind of leather constituting the raw material for processing natural leather products is not limited to the sheep, deer, and cow leathers of Embodiments 1 to 4, but pork, mink, chinchilla, mole, fox, weasel, camel, kangaroo, It is also possible to use leather such as reindeer, elk and lizard.

  Furthermore, in the above embodiment, a sheet-like material was used as a raw material for processing natural leather products, but the form of the raw material for processing natural leather products is not limited to the above embodiment, and the shape is not limited. Absent.

  Further, in the above embodiment, the natural leather product processing material is subjected to water repellent treatment using a high-pressure fluid as a medium, and thus the natural leather product processing material subjected to such water repellent treatment is processed into a desired shape. Natural leather products will be manufactured, but not limited to this, after processing natural leather products into a desired shape to produce natural leather products, high pressure fluid is used as a medium for the natural leather products. It is also possible to perform the water repellent treatment directly. Incidentally, in the case of relatively small natural leather products such as business card holders and wallets, it is possible to suitably apply water repellent treatment using a high-pressure fluid directly as described above.

  Examples of the present invention will be described below.

Example 1
In this example, a natural leather product processing sheet made of sheep leather was cut into a size of 20 cm × 20 cm as a sample. The sample weight was 11.3 g. A sample of a natural leather product processing sheet made of sheep leather was loaded into a high-pressure cell having a volume of 300 ml, and liquefied carbon dioxide was introduced into the high-pressure cell with a high-pressure pump and maintained at a pressure of 20 MPa and a temperature of 40 ° C. for 1 hour. Carbon dioxide was circulated at a speed of 0.2 m ³ / h for 4 hours. The speed of carbon dioxide in this case is the flow rate per unit time of carbon dioxide at room temperature and atmospheric pressure, and was measured using an integrating flow meter.

  The effluent fluid was cooled and trapped, resulting in a colored extract. Subsequently, the back pressure valve was opened to reduce the pressure in the system to atmospheric pressure. The weight of the sheep leather sample after this operation was 9.4 g, and a weight reduction (degreasing rate) of 16.8% was observed. It is recognized that impurities such as fats and oils contained in the sheep leather sample were removed by this.

Next, the high pressure cell containing the dry leather material from which impurities such as fats and oils have been removed in this way is depressurized with a vacuum pump, and a fluorine resin dissolved in a petroleum hydrocarbon solvent is used as a water repellent component. A high-pressure cell was filled with about 1.2 times the weight of sheep leather weight of a water repellent (trade name Novatec) manufactured by Daikin Industries, Ltd. Thereafter, high-pressure carbon dioxide was introduced and held at 20 MPa and 50 ° C. for 4 hours, and then the back pressure valve was opened and the pressure was reduced to atmospheric pressure at a rate of 0.1 m ³ / h, and a leather sample was taken out. As a result of measuring the weight of the sample, it was 10.1 g, and a weight increase (injection rate) of 7.4% was observed compared to before injection of the water repellent. Thus, it was confirmed that the water repellent component was provided in the sheep leather sample.

(Example 2)
In this example, ten sheets of natural leather product processing sheets made of sheep leather were cut into a size of 5.5 cm × 10 cm were used as samples. The total weight of these 10 samples was 15.0 g. Ten sheep leather samples were stacked and loaded into a high-pressure cell having a capacity of 300 ml, and liquefied carbon dioxide was introduced into the high-pressure cell with a high-pressure pump and maintained at a pressure of 20 MPa and a temperature of 40 ° C. for 1 hour, and then for 4 hours and 0.2 m. Carbon dioxide was circulated at a rate of ³ / h. The rate of carbon dioxide was measured using an integrating flow meter as in Example 1. The effluent fluid was cooled and trapped, resulting in a colored extract. Subsequently, the back pressure valve was opened to reduce the pressure in the system to atmospheric pressure.

  The weight of the sheep leather sample after this operation was 12.7 g, and a weight reduction (degreasing rate) of 15.3% was observed. It is recognized that impurities such as fats and oils contained in the sheep leather sample were removed by this.

Next, the high pressure cell containing the dry leather material from which impurities such as fats and oils have been removed in this way is depressurized with a vacuum pump, and a fluorine resin dissolved in a petroleum hydrocarbon solvent is used as a water repellent component. About 1.2 times the amount of water repellent (trade name Novatec) manufactured by Daikin Industries, Ltd. with respect to the weight of sheep leather was filled in a high-pressure cell. Thereafter, high-pressure carbon dioxide was introduced and held at 20 MPa and 50 ° C. for 4 hours, and then the back pressure valve was opened and the pressure was reduced to atmospheric pressure at a rate of 0.1 m ³ / h, and a leather sample was taken out. As a result of measuring the weight of the sample, it was 13.2 g, and an increase in weight (injection rate) of 3.9% was observed compared to before injection of the water repellent. Thus, it was confirmed that the water repellent component was provided in the sheep leather sample.
In this example, a total of 10 leather samples were stacked and loaded, but nevertheless, removal of impurities and penetration of the water repellent were performed uniformly on all 10 leather samples. I was able to.

(Example 3)
In this example, a natural leather product processing sheet made of deer leather was cut into a size of 20 cm × 20 cm as a sample. The sample weight was 10.1 g. This deer leather sample was loaded into a high-pressure cell having a capacity of 300 ml, and liquefied carbon dioxide was introduced into the high-pressure cell with a high-pressure pump and maintained at a pressure of 20 MPa and a temperature of 40 ° C. for 1 hour, and then for 4 hours, 0.2 m ³ / h. Carbon dioxide was circulated at a speed of The rate of carbon dioxide was measured using an integrating flow meter as in Example 1. The effluent fluid was cooled and trapped, resulting in a colored extract. Subsequently, the back pressure valve was opened to reduce the pressure in the system to atmospheric pressure.

  The weight of the deer leather sample after this operation was 7.8 g, and a 22.8% weight reduction (degreasing rate) was observed. As a result, it is recognized that impurities such as fats and oils contained in the deer leather sample have been removed.

Next, the high-pressure cell containing the dry leather material from which impurities such as fats and oils have been removed in this way is depressurized with a vacuum pump, and a fluorine-based resin dissolved in a petroleum hydrocarbon solvent is used as a water-repellent component. About 1.2 times the amount of water repellent (trade name Novatec) manufactured by Daikin Industries, Ltd. with respect to the weight of deer leather was filled in a high pressure cell. Thereafter, high-pressure carbon dioxide was introduced and held at 20 MPa and 50 ° C. for 4 hours, and then the back pressure valve was opened and the pressure was reduced to atmospheric pressure at a rate of 0.1 m ³ / h, and a leather sample was taken out. As a result of measuring the weight of the sample, it was 8.5 g, and an increase in weight (injection rate) of 8.3% was recognized compared to before injection of the water repellent. This confirmed that the water repellent component was provided in the deer leather sample.

Example 4
In this example, ten sheets of natural leather product processing sheets made of deer leather were cut into a size of 5.5 cm × 10 cm were used as samples. The total weight of these 10 samples was 13.0 g. Ten deer leather samples were stacked and loaded into a high-pressure cell having a capacity of 300 ml, and liquefied carbon dioxide was introduced into the high-pressure cell with a high-pressure pump and maintained at a pressure of 20 MPa and a temperature of 40 ° C. for 1 hour, and then for 4 hours and 0.2 m. Carbon dioxide was circulated at a rate of ³ / h. The rate of carbon dioxide was measured using an integrating flow meter as in Example 1. The effluent fluid was cooled and trapped, resulting in a colored extract. Subsequently, the back pressure valve was opened to reduce the pressure in the system to atmospheric pressure.

  The weight of the deer leather sample after this operation was 10.1 g, and a weight reduction (degreasing rate) of 22.3% was observed. As a result, it is recognized that impurities such as fats and oils contained in the deer leather sample have been removed.

Next, the high-pressure cell containing the dry leather material from which impurities such as fats and oils have been removed in this way is depressurized with a vacuum pump, and a fluorine-based resin dissolved in a petroleum hydrocarbon solvent is used as a water-repellent component. The high-pressure cell was filled with about 1.2 times the amount of water repellent (trade name Novatec) manufactured by Daikin Industries, Ltd. with respect to the deer leather weight. Thereafter, high-pressure carbon dioxide was introduced and held at 20 MPa and 50 ° C. for 4 hours, and then the back pressure valve was opened and the pressure was reduced to atmospheric pressure at a rate of 0.1 m ³ / h, and a leather sample was taken out. As a result of weighing the sample, the weight was 10.8 g, and a weight increase (injection rate) of 6.9% was observed compared to before injection of the water repellent. This confirmed that the water repellent component was provided in the deer leather sample.
In this example, a total of 10 leather samples were stacked and loaded, but nevertheless, removal of impurities and penetration of the water repellent were performed uniformly on all 10 leather samples. I was able to.

(Example 5)
In this example, a natural leather product processing sheet made of cowhide was cut into a size of 20 cm × 20 cm as a sample. The sample weight was 16.7 g. The cowhide sample was loaded into a high-pressure cell having a capacity of 300 ml, and liquefied carbon dioxide was introduced into the high-pressure cell with a high-pressure pump and maintained at a pressure of 20 MPa and a temperature of 40 ° C. for 1 hour, and then at a rate of 0.2 m ³ / h for 4 hours. Circulated carbon dioxide. The rate of carbon dioxide was measured using an integrating flow meter as in Example 1. The effluent fluid was cooled and trapped, resulting in a colored extract. Subsequently, the back pressure valve was opened to reduce the pressure in the system to atmospheric pressure.

  The weight of the cowhide sample after this operation was 15.2 g, and a weight reduction (degreasing rate) of 9.0% was observed. As a result, it is recognized that impurities such as fats and oils contained in the cowhide sample have been removed.

Next, the high pressure cell containing the dry leather material from which impurities such as fats and oils have been removed in this way is depressurized with a vacuum pump, and a fluorine resin dissolved in a petroleum hydrocarbon solvent is used as a water repellent component. About 1.2 times the amount of the water repellent (trade name Novatec) manufactured by Daikin Industries, Ltd. with respect to the weight of the leather is filled in the high pressure cell. Thereafter, high-pressure carbon dioxide was introduced and held at 20 MPa and 50 ° C. for 4 hours, and then the back pressure valve was opened and the pressure was reduced to atmospheric pressure at a rate of 0.1 m ³ / h, and a leather sample was taken out. As a result of measuring the weight of the sample, it was 16.3 g, and a weight increase (injection rate) of 7.2% was observed compared to before injection of the water repellent. This confirmed that the water repellent component was provided in the deer leather sample.

(Example 6)
In this example, ten sheets of natural leather product processing sheets made of cowhide were cut into a size of 5.5 cm × 10 cm were used as samples. The total weight of the sample was 25.3 g. Ten cow leather samples were stacked and loaded into a high-pressure cell with a capacity of 300 ml, and liquefied carbon dioxide was introduced into the high-pressure cell with a high-pressure pump and maintained at a pressure of 20 MPa and a temperature of 40 ° C. for 1 hour, and then for 4 hours, 0.2 m ³ / Carbon dioxide was circulated at a rate of h. The rate of carbon dioxide was measured using an integrating flow meter as in Example 1. The effluent fluid was cooled and trapped, resulting in a colored extract. Subsequently, the back pressure valve was opened to reduce the pressure in the system to atmospheric pressure.

  The weight of the cowhide sample after this operation was 23.2 g, and a weight reduction (degreasing rate) of 8.3% was observed. As a result, it is recognized that impurities such as fats and oils contained in the cowhide sample have been removed.

Next, the high pressure cell containing the dry leather material from which impurities such as fats and oils have been removed in this way is depressurized with a vacuum pump, and a fluorine resin dissolved in a petroleum hydrocarbon solvent is used as a water repellent component. The high-pressure cell was filled with about 1.2 times the amount of water repellent (trade name Novatec) manufactured by Daikin Industries, Ltd. with respect to the weight of the leather. Thereafter, high-pressure carbon dioxide was introduced and held at 20 MPa and 50 ° C. for 4 hours, and then the back pressure valve was opened and the pressure was reduced to atmospheric pressure at a rate of 0.1 m ³ / h, and a leather sample was taken out. As a result of measuring the weight of the sample, it was 24.3 g, and a 4.7% increase in weight (injection rate) was observed compared to before injection of the water repellent. This confirmed that the water repellent component was provided in the deer leather sample.
In this example, a total of 10 leather samples were stacked and loaded, but nevertheless, removal of impurities and penetration of the water repellent were performed uniformly on all 10 leather samples. I was able to.

(Summary of Examples)
As described above, the degreasing rate and the injection rate for the leather samples in Examples 1 to 6 are as shown in Table 1 and FIG.

  As is clear from Table 1 and FIG. 5, good results were obtained for the degreasing rate and the injection rate for all leather samples. The injection rate was similar in all leather samples, but the degreasing rate was in the order of deer leather, sheep leather, and cow leather. In addition, in the case where the number of samples was one as compared with the case where the number was ten, both the degreasing rate and the injection rate were better. However, even in the case of 10 sheets, the result is inferior, and it is recognized that the removal of impurities and the penetration of the water repellent were uniformly performed on all 10 leather samples as described above. .

(Other examples)
In Examples 1 to 6, the pressure in the step of removing impurities such as fats and moisture from the leather sample was 20 MPa, but the pressure in this step is not limited to 20 MPa. However, it is preferably 6 to 35 MPa. The critical pressure of carbon dioxide is 7.3 MPa, and at 6 MPa, which is a little lower than that, carbon dioxide becomes a so-called subcritical fluid. This is because the impurity removal effect is not always good. On the other hand, even if it exceeds 35 MPa, the improvement of the impurity removal effect is not recognized. From this viewpoint, the pressure is more preferably 10 to 25 MPa.

Moreover, in the said Example 1 thru | or 6, although the temperature in the process of removing impurities, such as said fats and oils, was 40 degreeC, this temperature is not limited to 40 degreeC of this Example. However, it is preferable that it is 30-50 degreeC. The critical temperature of carbon dioxide is 31 ° C., and at 30 ° C., which is a little lower than that, carbon dioxide is in a so-called subcritical state, and when the temperature is lower than that, the extraction action by the carbon dioxide as a fluid is slightly reduced, This is because the impurity removal effect is not always good. On the other hand, if it exceeds 50 ° C., the natural leather material may be deteriorated. From this viewpoint, the temperature is more preferably 35 to 45 ° C.

  Furthermore, in Examples 1 to 6, the holding time at the predetermined pressure and temperature of 20 MPa and 40 ° C. was set to 1 hour in the impurity removal step, but this holding time is not limited to this example. . However, it is preferably 30 minutes to 2 hours. If it is less than 30 minutes, the effect of carbon dioxide penetrating into the leather sample may be reduced, and even if held for more than 2 hours, no further improvement in effect will be observed. is there.

  Further, in Examples 1 to 6, the time for circulating carbon dioxide in the impurity removal step is 4 hours, but the circulation time is not limited to the examples. However, it is preferably 1 hour to 5 hours. This is because if the time is less than 1 hour, the effect of removing impurities in the leather sample may be reduced, and even if the holding is performed for more than 5 hours, no further improvement in the effect is observed.

  Further, in Examples 1 to 6, the pressure in the step of allowing the water repellent to penetrate the leather sample was 20 MPa, but the pressure in this step is not limited to 20 MPa. However, it is preferably 6 to 35 MPa. The critical pressure of carbon dioxide is 7.3 MPa. At a pressure of 6 MPa, which is slightly lower than that, carbon dioxide becomes a so-called subcritical fluid state. This is because the effect of penetrating the water repellent is not necessarily good. On the other hand, even if it exceeds 35 MPa, the improvement of the penetration effect is not recognized. From this viewpoint, the pressure is more preferably 10 to 25 MPa.

  In Examples 1 to 6, in the step of allowing the water repellent to permeate the leather sample, the temperature when held at a predetermined pressure of 20 MPa for 4 hours was 50 ° C., but this temperature is also limited to this example. It is not a thing and can set in the range of 40-50 degreeC. However, it is desirable that the fluorine-based resin used in the above-described examples as a water repellent is used at a high vapor pressure, and for that purpose, the temperature is such that the material of the leather sample does not deteriorate and is as high as possible. It is desirable to set it as temperature, and from that viewpoint, it is desirable to set it as 50 degreeC as mentioned above. This is because the higher the temperature and the higher the vapor pressure, the more suitably the water repellent made of a fluororesin can penetrate into the leather sample.

  Further, in Examples 1 to 6, in the step of infiltrating the water repellent agent into the leather sample, the time for holding at a predetermined pressure and temperature of 20 MPa and 50 ° C. was set to 4 hours. It is not limited to. However, it is preferably 1 hour to 5 hours. If it is less than 1 hour, there is a possibility that the effect of penetrating the water repellent into the leather sample may be reduced, and even if the holding is performed for more than 5 hours, no further improvement in penetration effect is observed. is there.

Further, in Examples 1 to 6, the rate at which carbon dioxide is circulated in the impurity removal step is 0.2 m ³ / h, but this rate is not limited to this example. However, it is preferably 0.05 to 0.5 m ³ / h. There is a possibility that impurity removal effect and 0.05m is less than ³ / h is poor, and also beyond the 0.5 m ³ / h, except that the improvement in the further effect not observed, the outlet of the back pressure valve This is because the gas may be frozen and clogged.

(Test Example 1)
In order to confirm the water repellency function of each leather material subjected to water repellency in the above examples, the water absorption was evaluated according to the leather test method water absorption (water absorption) of JISK-6550.

  The test was carried out by measuring the amount of weight increase after the 5.5 cm × 10 cm samples obtained in Examples 2, 4, and 6 were immersed in water for 4 hours together with an unprocessed material as a comparative example. It was. The test results are shown in Table 2. In Table 2, the smaller the value, the smaller the water absorption and the higher the water repellent function.

  As is clear from Table 2, the water absorption of all the leather samples was reduced by applying water repellent treatment as in the above example as compared to the raw leather material. That is, it was confirmed that a water repellent function was imparted.

(Test Example 2)
Next, the water resistance of the sheep leather samples subjected to the water-repellent treatment in the above examples was measured in accordance with the water resistance test method (b) water resistance test (spray test) of textile products of JISL-1092.

  The test was carried out by dropping a drop of water into the 20 cm × 20 cm sample of sheep leather obtained in Example 1 and measuring the area of the penetration, and comparing it with an unprocessed material. The evaluation criteria for the area are as follows. The larger the number, the higher the water resistance.

1: Wet on the entire surface.
2: Shows wetting on half of the surface, with small individual wetting penetrating the sample.
3: The surface shows small individual water droplets.
4: What does not wet on the surface, but shows wetness in the form of small water droplets.
5: No wetness or water droplet adhesion on the surface.

The test results are shown in Table 3.

  As is clear from Table 3, the unprocessed one of the comparative example had an evaluation of 1, whereas the first example had an evaluation of 3, and a better result was obtained than the unprocessed one. It was. In particular, it is recognized that good results have been obtained in this test for sheepskin leather materials that are highly utilized as sports gloves and that are particularly required to have a water-repellent function.

(Test Example 3)
Next, the dynamic water resistance of the sheep leather samples subjected to the water-repellent processing in the above-mentioned examples was measured. In the test, the 5.5 cm × 10 cm sheep leather sample obtained in Example 2 was repeatedly bent using a dynamic waterproof testing machine together with an unprocessed material as a comparative example, and the number of bendings when water exuded. And measuring the water absorption at that time.

As the dynamic waterproof tester, the one with the following specifications was used.
Bending speed: 60 cpm (1 cps)
Bending stroke: Max 10cm
Span: 40mm
Counter: 4 digits

  This dynamic waterproof tester performs a waterproof test while bending a sample. In general, leather is very slow in water permeability if it is left on the water. In this apparatus, one surface is in contact with water to perform a bending test, and the waterproofness is evaluated by the time until water penetrates to the other surface or the number of bending times and the amount of deflection applied to the test piece. It shows that a water-repellent function is so high that the frequency | count of bending is large and a water absorption rate is small. The test results of water resistance and dynamic water resistance are shown in Table 3 above.

As is apparent from the results in Table 3, the sheep material is subjected to water repellent treatment as in the above-described examples, and the number of flexing is 20 times or more compared to the raw leather material. Was about half of the raw leather material. Therefore, it was confirmed that the water resistance was improved, that is, the water repellent function was given. In particular, it is recognized that good results have been obtained in this test for sheepskin leather materials that are highly utilized as sports gloves and that are particularly required to have a water-repellent function.

  As is clear from the results in Tables 2 and 3, it was found that the water-repellent functionality of the samples after the degreasing and water-repellent processing was significantly improved compared to the samples before the processing.

The schematic block diagram of the manufacturing apparatus of the raw material for processing natural leather products which provided the water-repellent component as one Embodiment. The principal part expanded sectional view which shows the structure of leather. The principal part expanded sectional view which shows the structure of the leather of the state which peeled the silver layer. The schematic block diagram of the manufacturing apparatus for the processing of the natural leather product which provided the water repellent component of other embodiment. The graph which shows the degreasing rate and injection rate with respect to each leather sample.

Explanation of symbols

    1 ... High pressure cell 9 ... Skin

Claims (10)

  A material for processing natural leather products, in which water-repellent components are permeated into the tissue and fibers of natural leather using a high-pressure fluid as a medium.   The material for processing a natural leather product according to claim 1, wherein the water-repellent component is one or more of a fluororesin, a silicone resin, and a fluorosilicone resin.   The natural leather product processing material according to claim 1 or 2, wherein the natural leather is mammalian leather or fur, avian fur, or a reptile leather.   A natural leather product comprising the natural leather product processing material according to any one of claims 1 to 3.   A natural leather product characterized in that a water-repellent component is permeated into natural leather tissues and fibers using a high-pressure fluid as a medium.   A method for producing a material for processing a natural leather product, characterized in that a water-repellent component is infiltrated into a natural leather tissue or fiber using a high-pressure fluid as a medium.   The method for producing a raw material for processing a natural leather product according to claim 6, wherein impurities such as lipid and water remaining in the natural leather tissue and fiber are removed before the water-repellent component is infiltrated into the natural leather tissue and fiber. .   The method for producing a material for processing natural leather products according to claim 7, wherein impurities are removed using a high-pressure fluid.   The method for producing a material for processing a natural leather product according to any one of claims 6 to 8, wherein the medium is a mixture of a high-pressure fluid and a solvent that dissolves the water-repellent component.   The method for producing a material for processing natural leather products according to claim 9, wherein the solvent for dissolving the water-repellent component is one or two of petroleum hydrocarbon and fluorine hydrocarbon.

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