JPS5822591B2 - Suede Yogi Kakuno Seizou Hohou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing suede-like fake leather that has excellent breathability and closely resembles natural suede in appearance and feel.

Conventional suede-like imitation leather is known to be made by flocking short fibers on a raw cloth or synthetic resin sheet, or by grinding the surface of sponge leather such as vinyl chloride, but the former is made by flocking. The short fibers were easily removed, the latter had low strength, and both were far from natural suede in terms of appearance and texture.

In particular, it is difficult to grind the surface of sponge leather to a uniform thickness, and it is extremely difficult to obtain an even suede-like appearance.

In addition, a polyurethane elastomer-coated base material is wet-coagulated and solvent removed to form a polyurethane film having a honeycomb-like structure consisting of numerous vertically arranged pores, and the middle of the honeycomb-like structure is cut with a slitter to remove the inside. There is a way to expose the pores of the leather to obtain suede-like faux leather.

However, with this method, it is difficult to adjust the manufacturing conditions to form a honeycomb-like structure in which pores with uniform diameters are uniformly distributed, and it is difficult to adjust the manufacturing conditions to form a honeycomb-like structure in which pores with uniform diameters are evenly distributed. This is difficult because the fake leather is soft and thin, resulting in uneven color and luster, which reduces the product value.

Furthermore, in the method of peeling the foamed PVC leather into two pieces from the middle, it was difficult to peel the leather evenly and therefore it was difficult to obtain a uniform and even suede appearance.

On the other hand, the present inventors also tried a method of mixing an excessive amount of an underwater foaming agent into a polyurethane nidistomer to form a wet simulated leather with a high foam density and grinding the epidermis, but it was difficult to obtain a uniform pore density. .

Attempts have also been made to apply a foaming agent to the surface of the PVC sheet and foam it to make the sheet surface rough and suede-like, but it has been difficult to obtain uniform, dense pores.

The present invention relates to a new manufacturing method that improves the shortcomings of these conventional suede-like fake leathers, and provides a method for manufacturing suede-like fake leather that has excellent breathability, flexibility, and extremely resembles natural suede in appearance and texture. This is related.

That is, the gist of the present invention is to mechanically mix gas into a foamable polymer sheet containing a blowing agent, another foamable polymer sheet, or a paste or solution synthetic resin or rubber compound. A foaming agent which is composed of a foaming agent having a decomposition temperature equal to or lower than that of the foaming agent at the intermediate contact surface with another foamable polymer sheet, or a foaming agent comprising the foaming agent as a main component and a plasticizer. A layer is formed to form a laminated sheet, the laminated sheet is heated to foam the foaming agent in the foamable polymer sheet and the foaming agent layer, and then a foamed polymer sheet is produced from the foamed foaming agent layer. The present invention involves a method of obtaining suede-like pseudo-leather by peeling off a foamed polymer sheet or a foamed polymer sheet.

To explain the present invention in more detail, a blowing agent or a blowing aid is blended into a compound for molding a polymer sheet such as synthetic resin such as vinyl chloride, polyurethane, or acrylic or rubber, or a gas is mechanically mixed. Then, an unfoamed foamable polymer sheet or a cellular polymer sheet is formed by a conventional method such as a calendering method or a coating method.

The foamable polymer sheet or foamable polymer sheet may be one in which a base fabric is laminated by topping, lamination, or the like.

Next, a powdered foaming agent or foaming accelerator is powder-coated on the resin or rubber layer surface of the foamable polymer sheet or the foaming polymer sheet, or a paste-like foaming agent or foaming accelerator is applied. to form a foaming agent layer.

Further, another foamable polymer sheet formed as described above is laminated and integrated with the upper surface of the foaming agent layer by heat-pressing, or a foaming agent is blended on the upper surface of the foaming agent layer, or a gas is mechanically added to the upper surface of the foaming agent layer. A foamable polymer sheet or a foamable polymer sheet in which a paste or solution of a synthetic resin or rubber compound mixed with is applied and heated, semi-gelled, or heated and dried to form air bubbles inside. form things.

A laminated sheet of two foamable polymer sheets having a foaming agent layer in the middle formed as described above or a blend of the foamable polymer sheet and a paste or solution synthetic resin or rubber. A laminated sheet with another cellular polymer sheet into which gas has been mechanically mixed is passed through a heating furnace and heated,
The foaming agent dispersed in the foamable polymer sheet and the foaming agent in the foaming agent layer are foamed.

After the blowing agent is foamed, the laminated sheet is cooled, and numerous bubbles are formed and the blowing agent layer portion with a high density of foamed cells, that is, the upper and lower foamed polymer sheets or cellular polymer sheets are brought into contact with each other. Peel off from the surface to obtain two pieces of suede-like faux leather.

The foamable polymer sheet or foamable polymer sheet is made of a synthetic resin such as vinyl chloride, polyurethane, or acrylic, a polymer such as natural rubber or synthetic rubber, a plasticizer, a blowing agent,
Formed into a film by a calendar method from a compound consisting of foaming accelerators, stabilizers, pigments, etc., and then topped with a base material such as knitted or woven fabric or nonwoven fabric to form a sheet, or vinyl chloride, acrylic, or polyurethane. A paste or solution of a synthetic resin such as vinyl acetate mixed with a foaming agent, a foaming accelerator, and other general additives is applied to a base material such as a textile fabric or nonwoven fabric, and then heated and dried to form a sheet-like product. Alternatively, the mixture is applied onto a releasable carrier such as release paper or synthetic resin film, and after heating and drying, it is laminated to the base material with an adhesive if necessary, and the releasable carrier is peeled off to form a sheet. A polymer sheet shaped product formed by a conventional method is used.

In addition, when the gas is mechanically mixed into the paste-like synthetic resin, pulp, fiber, inorganic powder,
It is also possible to incorporate short fibers.

As mentioned above, the foamable polymer sheet contains an unfoamed blowing agent dispersed therein. must be used in combination.

The method of forming the foaming agent layer on the upper surface of the foamable polymer sheet or foamable polymer sheet is to powder-coat a powdered foaming agent or foaming accelerator, or to coat the foaming agent or foaming accelerator with powder. A paste-like mixture consisting of a plasticizer etc. is applied.

The blowing agent mixture is partially applied in a pattern onto the top surface of the expandable polymer sheet, and a subsequent foaming step results in partial foaming to produce a decorative sheet with a partially suede appearance. It is also possible to obtain

The coating method includes powder coating, spraying, a doctor knife coater, a roll coater such as gravure printing and flexo printing, a screen, and printing.

The foaming agent and foaming accelerator are kneaded together with a plasticizer and the like using an ink mill or the like to prepare a paste-like mixture containing the foaming agent as the main component.

Ordinary organic blowing agents can be used as the blowing agent for the foamable polymer sheet, and is the blowing agent used to form the foaming agent layer equivalent to the decomposition temperature of the blowing agent in the foamable polymer sheet? It is preferable to adjust the decomposition temperature to be equal to or lower than the decomposition temperature of the blowing agent in the foamable polymer sheet by using a foaming agent having a decomposition temperature lower than that or by combining it with a foaming aid. .

The foaming agents used to form the foaming agent layer include inorganic ones such as ammonium carbonate, sodium bicarbonate, and sodium nitrite, and organic ones such as paratoluenesulfonyl hydrazide and its derivatives, 4,4'-oxybis Benzene sulfonyl hydrazide, azobisisobutyronitrile, dinitropentamethylenetetramine, azodicarboxylic acid amide, etc. are used.

The foaming accelerator is used in combination with one of the above foaming agents with a high foaming temperature, and for dinitrosopentamethylenetetramine, an organic acid such as salicylic acid, benzoic acid, maleic acid, or a urea-based foaming accelerator is used. For azodicarboxylic acid amide, metal oxides such as zinc oxide, metal salts such as cadmium stearate, zinc stearate, lead stearate, urea foaming accelerators, etc. are used.

As the plasticizer or processing oil that turns the foaming agent into a paste, common ones such as phthalate ester plasticizers such as dioctyl phthalate, dibutyl phthalate, and butylbenzyl phthalate, and spindle oil are used.

The foaming agent for forming the foamable polymer sheet is mainly a conventional organic type, such as paratoluenesulfonyl hydrazide and its derivatives, 4,4'-oxybisbenzenesulfonylhydracite, dinitrosopentamethylenetetramine, Azodicarboxylic acid amide etc. are used.

The two sheets of foamable polymer are crimped and integrated using a heating device commonly used for lamination, and the sheet is heated and then passed through a pressure roll.

To foam the foaming agent, the laminated sheet is heated and foamed by passing it through a heating oven consisting of an infrared heater, gas heater, steam heater, or the like.

The temperature in the heating oven is 140°C to 280°C, preferably 180°C to 250°C.

The above heating causes the foaming agent to foam, but since the foaming agent in the foaming agent layer foams at a lower temperature than the foaming agent in the foamable polymer sheet, first Foaming occurs from the foaming agent layer on the contact surface of the combined sheet, and foaming occurs centering around the foaming core generated by the foaming gas throughout the layer of the foamable polymer sheet, forming continuous cells. Ru.

In addition, since the foaming agent layer has a higher content density of the foaming agent than the polymer sheet, the density of the cells formed through active foaming is higher than that in the polymer sheet. The size is also large.

Therefore, in the step of peeling off the foamed polymer sheet or cellular polymer sheet below -L after foaming is completed, it can be peeled off very easily from the contact surface and a sheet with uniform thickness can be obtained.

Also, the peeled surface has a high cell density, and the cells are divided into two, forming a shape that closely resembles suede-like appearance.

To peel off the foamed polymer sheet or cellular polymer sheet, one end of the laminated sheet is peeled into two parts using a nail or knife, separated and pulled in both directions, and then each end is placed between two rolls. The whole laminated sheet is peeled off by wrapping it around the sheet.

The present invention is carried out as described above (by foaming a foaming agent inside a foamable polymer sheet, further foaming at the contact surface of two polymer sheets, and peeling the foam into two foamed polymer sheets). As a result, it closely resembles natural suede in appearance and texture, and in particular, a suede-like pseudo-leather with the same color and luster with no unevenness in the cut surface of the bubbles on the surface can be obtained.

In addition, by forming a foaming agent layer partially in a pattern on the surface of a foamable polymer sheet or a cellular polymer sheet, it has a partially suede appearance, which is highly decorative and is unprecedented. A sheet-like product is obtained.

The manufacturing method is extremely easy, no new equipment is required, the manufacturing efficiency is high, and low-cost products can be mass-produced.Therefore, it can be used in a wide range of applications as a substitute material for leather in clothing, bags, shoes, etc.

Next, the present invention will be explained with reference to Examples.

Note that in the description, parts represent parts by weight.

Example 1 100 parts of vinyl chloride resin, 60 parts of dioctyl phthalate (plasticizer), 2 parts of Cd-Ba stabilizer, 3 parts of azodicarboxylic acid amide (foaming agent), 0.3 part of stearic acid, 3 parts of pigment (brown) A PVC sheet with a thickness of 0.3 mm is topped with a raw knitted cloth using a calendar to obtain unfoamed PVC leather.

Next, 100 ml of bicarbonate of soda was applied to the surface of the PVC layer of the unfoamed leather.
A blowing agent dispersion containing 500 parts of butylbenzyl phthalate was applied using a gravure roll and dried by heating at 80° C. for 1 minute.

Next, two sheets of unfoamed PVC leather coated with the foaming agent formed as described above are prepared, and the foaming agent coated surfaces are bonded together under heat and pressure to be integrated.

Next, heat it in a heating oven at 200 ° C for 3 minutes,
After foaming and air cooling, the two foamed sheets were peeled from the contact surface to obtain two suede-like pseudo-leather sheets.

Example 2 100 parts of hinyl chloride resin, 55 parts of dioctyl phthalate (plasticizer), 5 parts of epoxy plasticizer, 3 parts of zinc stabilizer,
A vinyl chloride paste consisting of 3 parts of azodicarboxylic acid amide and 3 parts of a pigment (black) was applied to a thickness of 0.3mm on a release paper and heated at 130°C for 3 minutes to semi-gel the vinylchloride paste.

Next, apply adhesive and attach the knitted raw cloth to 130'0.
Heat and dry for 3 minutes and peel off the release paper to obtain unfoamed PVC leather.

Next, sodium bicarbonate was added to the surface of the PVC layer of the unfoamed PVC leather.
A blowing agent dispersion containing 100 parts of butylbenzyl phthalate and 250 parts of butylbenzyl phthalate was applied using a gravure roll and dried by heating at 80°C for 1 minute.

Next, apply the above-mentioned PVC paste to a thickness of 0.3 mm on the dry foaming agent-coated surface, heat it at 130°C for 3 minutes to semi-gelatinize the PVC paste, then apply an adhesive and attach the stockinette cloth. Laminate and heat dry at 130'C for 3 minutes.

Next, this laminated leather was heated and foamed in a heating oven at 180° C. for 5 minutes, and after cooling, it was peeled off from the contact surface of the two foamed PVC leathers to obtain two suede-like fake leathers.

Claims (1)

[Scope of Claims] 1. The intermediate layer, which is the contact surface of two foamable polymer sheets blended with a foaming agent, is made of a foaming agent having a decomposition temperature equal to or lower than that of the foaming agent, or the foaming agent is A foaming agent layer consisting of a foaming agent as a main component and a plasticizer is formed into a laminated sheet, the laminated sheet is heated to foam the foaming agent in the foaming agent layer in the foamable polymer sheet, and then A method for producing suede-like fake leather, which comprises peeling off two foamed polymer sheets from the foamed foaming agent layer. 2. An intermediate layer that is the contact surface between a foamable polymer sheet containing a blowing agent and another foamable polymer sheet containing a paste or solution of a synthetic resin or rubber compound mechanically mixed with gas. A foaming agent layer made of a foaming agent having a decomposition temperature equal to or lower than that of the foaming agent or consisting of the foaming agent as a main component and a plasticizer is formed on the foaming agent to form a laminated sheet, and the laminated sheet is heated. The foaming agent in the foamable polymer sheet and the foaming agent in the foaming agent layer are foamed, and then the foamed polymer sheet and other foamable polymer sheet are produced from the foamed foaming agent layer. A method for producing suede-like fake leather characterized by peeling.