KR20210062969A - Artificial leather and Manufacturing methoud for the same - Google Patents

Abstract

The present invention relates to a method for manufacturing artificial leather capable of forming a ventilation part and, more specifically, to a method for manufacturing artificial leather capable of manufacturing artificial leather that is easy to process and secures air permeability by forming a ventilation portion penetrating a resin skin layer and an adhesive layer, including a protrusion portion on the release paper, and to artificial leather manufactured by the manufacturing method.

Description

Artificial leather and manufacturing method thereof

The present invention relates to a manufacturing method of artificial leather, and more particularly, to a manufacturing method of artificial leather capable of ensuring air permeability without an additional process for forming a separate vent after manufacturing the artificial leather.

Background to the present disclosure is provided herein, which does not necessarily imply known art.

In general, artificial leather is a fabric made by forming a film with a synthetic resin such as PVC or PU (polyurethane) on a release paper embossed with a leather pattern or other predetermined pattern, and then synthesizing it with a woven, knitted or non-woven fabric using an adhesive. In general, there are two types of methods: dry method and wet method.

The dry method forms a film on the surface of the release paper with a polyurethane stock solution or solvent-type polyurethane (polyurethane dissolved in toluene, methyl edyl ketone (MEK)) resin, for example, a solvent-type polyurethane (PU) solution It is applied to a release paper (or a release film) and dried, then the release paper and the fabric are laminated through an adhesive, dried, and then the release paper is peeled from the film to form a film (skin layer) of artificial leather on the fabric.

The wet method uses a method such as padding with a resin that can form a film on the surface of the fabric or the entire fabric, for example, a solvent-type PU resin, or gravure on fabrics (fabric, knitted, non-woven) impregnated with synthetic resin. This is a method of forming a film by applying a PU resin to the surface.

However, since all of the artificial leathers manufactured by the conventional method described above form a film and then the film is adhered to the surface of the fabric with an adhesive, the surface of the fabric is completely blocked by the film, so there is no breathability effect like natural leather.

When the artificial leather manufactured as described above is used for shoes or vehicle seats, the durability due to moisture or salt generated in the human body is deteriorated due to insufficient ventilation. In particular, when artificial leather is used as the upper of a shoe, if breathability is not secured, an unpleasant odor may be generated.

In order to solve this problem, Korean Patent Application Laid-Open No. 2012-0133789 discloses a method of applying a water-soluble synthetic resin solution directly to the surface of a fabric after forming brushing on the fabric in artificial leather manufactured by a wet process. A method for imparting breathability by partially leaving the

However, the above method is limited to the wet process, and there is a problem in that it is not easy to control the ventilation hole for providing ventilation.

1. Republic of Korea Publication No. 10-2012-0133789 (2012.12.11.)

An object of the present invention is to provide a method for manufacturing artificial leather in which a ventilation portion capable of imparting breathability to artificial leather is formed.

Another object of the present invention is to provide a release paper for manufacturing artificial leather for forming a ventilation portion capable of imparting breathability to artificial leather.

Another object of the present invention is to provide an artificial leather with improved ventilation, including a ventilation part.

However, the objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

In order to solve the above problems, one aspect of the present invention provides a method for manufacturing artificial leather comprising the following steps:

preparing a release paper (S1);

forming a resin skin layer by applying a resin solution on the release layer of the release paper and drying (S2);

After forming an adhesive layer on the resin skin layer, laminating with a woven or non-woven fabric (S3); And

and removing the release paper from the resin skin layer to obtain artificial leather (S4),

In the step (S1) of preparing the release paper, the release paper is higher than the thickness to which the resin skin layer and the adhesive layer are applied, and thus includes a protrusion that penetrates the resin skin layer and the adhesive layer and comes into contact with the fabric.

In the manufacturing method, the release paper may include a substrate layer having irregularities on its surface and a release layer on the substrate layer.

In addition, the base layer includes at least one selected from the group consisting of polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), and polyvinylchloride (PVC). It may be formed by

In the release paper for the manufacturing method, the base layer may include a pattern layer provided with irregularities using a photocurable resin on a flat base layer.

In this case, the base layer includes at least one selected from the group consisting of polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), and polyvinylchloride (PVC). is formed, and the pattern layer is at least one selected from the group consisting of a polyurethane-based, polyacrylate-based, polyepoxy-based, polyurethane acrylate-based, polyester acrylate-based, polyepoxyacrylate-based and silicone-based UV curable resin. It can be formed with more than one species.

Another aspect of the present invention provides an artificial leather manufactured by the method for manufacturing artificial leather, the artificial leather including a fabric, a resin skin layer, and a ventilation part.

Another aspect of the present invention provides a release paper that can be used in the manufacturing method of the artificial leather, and includes a protrusion in a base layer or a pattern layer.

According to the present invention, the ventilation part can be formed by designing the release paper without going through a separate ventilation part forming process. In addition, the design of the ventilation part can be varied.

1 is a cross-sectional view of a release paper for forming a ventilation part according to an embodiment of the present invention, and a release paper including a ventilation part formed thereby - an artificial leather laminated state.

Before describing the present invention in detail below, it is understood that the terms used in the present specification are for describing specific embodiments and are not intended to limit the scope of the present invention, which is limited only by the scope of the appended claims. shall. All technical and scientific terms used in this specification have the same meaning as commonly understood by those of ordinary skill in the art unless otherwise stated.

Throughout this specification and claims, unless otherwise stated, the term "comprise, comprises, comprising" means to include the recited object, step or group of objects, and steps, and any other object It is not used in the sense of excluding a step, a group of objects, or a group of steps.

On the other hand, various embodiments and embodiments of the present invention may be combined with any other embodiments unless clearly indicated to the contrary. Any feature indicated to be particularly desirable or advantageous may be combined with any other feature and features indicated to be desirable or advantageous.

The artificial leather according to an embodiment of the present invention includes a fabric, an adhesive layer, and a resin skin layer, but includes a ventilation portion in which the adhesive layer and the resin skin layer are substantially absent on the surface of the fabric.

The fabric of the artificial leather may include a woven fabric, a knitted fabric, or a non-woven fabric including synthetic fibers or natural fibers. The fabric serves to support the resin skin layer, and the density and strength of the constituent fibers may be different depending on its use.

The fabric of artificial leather is an aggregate of thin strands of fibers regardless of its structure and weaving method, so a pore diameter occurs between the aggregated fibers and fibers. Therefore, although there may be a difference in air permeability, the fabric itself is the basic There is breathability.

Artificial leather to which breathability is imparted according to an embodiment of the present invention includes a ventilation part in which the fabric is directly exposed to the external environment. That is, the artificial leather to which the breathability is imparted according to an embodiment of the present invention includes a ventilation portion to which the skin layer including the adhesive layer and the resin is not substantially applied to the fabric supporting the artificial leather.

As long as the ventilation part can provide the required ventilation, there is no limitation in its shape or area. For example, when artificial leather is used for the upper of a shoe, the ventilation part may be one in which ventilation holes having a diameter of 1 mm or less are regularly or irregularly arranged.

Another example of the use of shoes may be in the form of a trademark, character, or other figure. In this case, since the area of the ventilation part is relatively large, it may be vulnerable to external moisture. Therefore, a fabric having a moisture-permeable and waterproof effect can be used. As a moisture-permeable and waterproof material that can be used, polyester or nylon is used as a base fabric, and a product coated with a film capable of expressing moisture-permeable and waterproof function on a fabric having a high density plain weave structure can be used. The weight of the fabric fabric may be 0.28 g ~ 1.05 g, and the thickness may be 0.10 mm ~ 0.71 mm, and the coating or laminating film may be microporous, monolithic, or bicomponent. And as a representative moisture-permeable waterproof fabric include a Gore-Tex (Gore-Tex ^ⓡ) of US Gore社, Donaldson社of tetra-Tex (Tetratex ^ⓡ), US BHA tekeunolriji社event (eVent ^ⓡ), Japanese Toray社of ent sealant A number of moisture-permeable and waterproof materials such as DT (Entrant DT) and Hill-tex ^{ⓡ from Hope Hill in Korea are on the market.}

The manufacturing method of artificial leather according to another embodiment of the present invention comprises the steps of preparing a release paper (S1), applying a resin solution on the release layer of the release paper and drying to form a resin skin layer (S2), and the resin After forming an adhesive layer on the skin layer and laminating it with a woven or non-woven fabric (S3), the release paper is transferred through a step (S4) of removing the release paper from the resin skin layer to obtain an artificial leather, and the unevenness of the release paper is transferred to the resin An artificial leather in which the fabric is laminated on the skin layer is obtained.

The release paper may include a substrate layer having irregularities on its surface and a release layer on the substrate layer. The base layer is formed by including at least one selected from the group consisting of polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), and polyvinylchloride (PVC). It may be a single layer. The release paper according to an embodiment of the present invention may include a structure capable of transferring figures, characters, or patterns such as natural leather on the surface of artificial leather.

The base layer may have irregularities in units of millimeters (mm) to micrometers (㎛) or irregularities in units of nanometers (nm). When the pattern of the base layer is relatively simple, the base layer is a group consisting of polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET) and polyvinylchloride (PVC). It may be a single layer formed including at least one selected from.

In addition, when the transfer pattern is complicated or a hologram is required, the base layer is formed including a pattern layer 402 with concavities and convexities using a photocurable resin on a flat base layer 403 as shown in FIG. 1 . It can be a layer. At this time, the base layer 403 is at least one selected from the group consisting of polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), and polyvinylchloride (PVC). can be formed including. The pattern layer 402 may be a UV-curable resin, which includes a polyurethane-based, polyacrylate-based, polyepoxy-based, polyurethane acrylate-based, polyester acrylate-based, polyepoxyacrylate-based and silicone-based UV-curable resin. At least one selected from the group consisting of may be included. Preferred UV-curable resins include urethane acrylate-based, epoxy acrylate-based, polyester acrylate-based, and silicone acrylate-based resins containing (meth)acrylate at the terminal of the molecule, and may react with cations at the terminal of the molecule. Epoxy-based and vinyl-based curable resins that can be used may also be included.

Regarding the photocurable resin of the pattern layer 402 , in order to practice the present invention, a person skilled in the art may appropriately select and use a photocurable resin that is easy to form a fine pattern. For example, a photocurable resin composition disclosed in Korean Patent Application Laid-Open No. 10-2014-0111603 (2014.09.19.) and the like may be used for the pattern layer 402 .

Meanwhile, the release layer 401 serves to allow the resin skin layer of the artificial leather and the release paper to be easily peeled off. The main component constituting the release layer can be used without limitation as long as it can achieve the above object. When the component constituting the skin layer of the artificial leather is polyurethane, silicone may be used in terms of securing releasability. In addition, when the component constituting the skin layer of the artificial leather is silicone, the release layer in which the non-silicone-based compound is the main component may be formed. In particular, when a more sophisticated shape such as a hologram is required for the transferred pattern, any one or more selected from the group consisting of Cr, Al, Ni, Si and alloys containing the same may be deposited, and the thickness is 10 to 1,000 Å. can be formed. When the release layer 20 is used as a metal deposition, the release effect may be lowered when the metal deposition layer is less than 10 Å, and when the metal deposition layer exceeds 1,000 Å, the accuracy of the pattern may be impaired. In terms of optimizing the release effect and transfer quality, the preferable thickness of the metal deposition layer may be 300 Å to 800 Å.

As a method of forming the unevenness on the surface of the base layer, a pattern may be formed by a method such as imprinting a resin. In the case of using an ultraviolet curing resin to form a precise pattern, a UV imprinting method may be used. .

The base layer 403 may be paper. When the base layer is paper, it is preferable when the mechanical strength of the release paper itself is required. In addition, the base layer 403 may be a film using a synthetic resin as a raw material. The synthetic resin may be polyester, polyamide, polypropylene, polyethylene, or the like, and in terms of forming an elaborate pattern and securing the quality of the transferred pattern layer, it is preferable to use a synthetic resin film as the base layer 403 . Therefore, in the present invention, the release paper is understood as a concept including a release film.

In the manufacturing method of artificial leather according to the embodiment of the present invention, the step of forming the resin skin layer (S2) is a step of applying and drying a resin solution on the release paper, and the resin solution is an organic solvent and a resin. A solvent-type resin solution containing water may be used, or a water-soluble resin solution containing water may be used.

The resin solution may further include various types of pigments and dyes to implement a color in addition to the resin and the organic solvent (or water). For example, it is preferable to mix 200 to 600 parts by weight of an organic solvent (or water, or a mixture thereof) with respect to 100 parts by weight of the resin, and to contain 0 to 20 parts by weight of a dye or pigment.

The resin may be polyurethane, polyolefin, polyvinyl chloride, enamel, polycarbonate, silicone, or the like.

The organic solvent may be methylethylketone (Methylethylketone, MEK), dimethylformamide (Dimethylformamide, DMF), dimethylacetamide (Dimethylacetamide, DMAc), and the like.

The resin skin layer may be formed to have an appropriate thickness in consideration of use, durability, and material cost.

In addition, the resin skin layer forming step (S2) may be repeated at least twice or more to form at least two or more resin skin layers including the first resin skin layer and the second resin skin layer. That is, the first resin skin layer is formed by first coating and drying the mixed solution on the release paper 400, and the second resin skin layer can be formed by the second application and drying of the mixed solution on the first resin skin layer. have.

The resin skin layer may be formed to a thickness of about 20 μm when one layer is applied. Therefore, when three layers are applied, the skin layer can be formed to a thickness of about 60 μm. According to another embodiment of the present invention, as illustrated in FIG. 1 , the resin skin layer 303 and the adhesive layer 302 are higher than the thickness at which the resin skin layer 303 is applied to the pattern layer 402 of the release paper. ) is provided with a release paper including a protrusion 404 whose end is in contact with the distal end 301 through it. The protrusion 404 forms a ventilation portion through the resin skin layer 303 and the adhesive layer 302 of the artificial leather 300 to be finally manufactured, so that the sum of the thicknesses of the resin skin layer 303 and the adhesive layer 302 . The height may be larger than that, and the height may be smaller than the sum of the thicknesses of the resin skin layer 303 , the adhesive layer 302 and the fabric 301 . In the present specification, the height of the protrusion is understood to mean a straight line distance from a horizontal line based on the lowest concave groove in the concave-convex structure formed in the pattern layer to a horizontal line based on an end of the protrusion adjacent to the distal end.

The step of laminating the fabric (S3) is a step of forming an adhesive layer on the resin skin layer and then laminating the fabric with the fabric to form an artificial leather. Referring to FIG. 1 as an example, it is a step of applying an adhesive on the resin skin layer 303 to form an adhesive layer 302 and laminating a fabric 301 such as a woven, knitted or non-woven fabric.

In the step of obtaining the artificial leather (S4), referring to FIG. 1 as an example, removing the release paper 400 from the resin skin layer 303 to obtain the artificial leather in which the unevenness on the release paper is transferred to the resin skin layer 303 is obtained. to be. There is no limitation on the method of removing the release paper, but it can be removed by applying a physical force to tear the release paper.

Manufacturing example

Manufacture of release film

A UV-curable resin is injected between a PET film (base layer) having a thickness of 100 μm and a stamp mold having irregularities and protrusions that can form a predetermined pattern, and the stamp mold is pressed to provide a constant space between the substrate layer and the stamp mold. thickness was maintained. After irradiating the PET surface with 500 mJ/cm 2 UV rays, the stamp mold was demolded and patterned irregularities and protrusions were formed on the surface of the PET to form a patterned layer on the PET substrate. Silicone was applied to a thickness of 0.3 to 1.0 μm on the cured pattern layer to form a release layer.

The composition of the UV curable resin of the pattern layer is shown in Table 1 below.

division weight% Remark SR259 30 UV curable monomer SR348 30 UV curable monomer SR351 NS 10 UV curable monomer SR506 NS 25 UV curable monomer IRGACURE 184 3 photopolymerization initiator IRGACURE TPO 2 photopolymerization initiator Sum 100

In Table 1, the UV-curable monomer is available from Satomer, and the photopolymerization initiator is available from Ciba.

Manufacture of artificial leather

A urethane composition prepared by mixing 100 parts by weight of polyurethane resin and 500 parts by weight of MEK was coated on the release film prepared above using a 200 μm coating bar, and dried in a hot air drying oven at 80° C. for 5 minutes to form a poly A urethane skin layer was formed. The above coating process was repeated three times to form a final polyurethane skin layer having a thickness of about 60 μm.

An adhesive was applied on the skin layer and a nonwoven fabric was laminated. Then, the polyurethane skin layer and the release layer of the release film were separated to obtain artificial leather.

Features, structures, effects, etc. exemplified in the above-described embodiments may be combined or modified by those of ordinary skill in the art to which the embodiments belong. Therefore, contents related to such combinations and modifications should be construed as being included in the scope of the present invention.

Claims (7)

preparing a release paper (S1);
forming a resin skin layer by applying a resin solution on the release layer of the release paper and drying (S2);
After forming an adhesive layer on the resin skin layer, laminating with a woven or non-woven fabric (S3); and
and removing the release paper from the resin skin layer to obtain artificial leather (S4),
In the step (S1) of preparing the release paper, the release paper is higher than the thickness to which the resin skin layer and the adhesive layer are applied, and includes a protrusion penetrating the resin skin layer and the adhesive layer to contact the fabric. manufacturing method. The method according to claim 1, wherein the release paper comprises a base layer having irregularities on its surface and a release layer on the base layer. The method of claim 2,
The base layer includes at least one selected from the group consisting of polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), and polyvinylchloride (PVC). A method for manufacturing artificial leather The method of claim 2,
The method for manufacturing artificial leather, wherein the base layer includes a pattern layer provided with irregularities using a photocurable resin on a flat base layer. The method of claim 4,
The base layer comprises at least one selected from the group consisting of polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET) and polyvinylchloride (PVC). become,
The pattern layer includes at least one selected from the group consisting of a polyurethane-based, polyacrylate-based, polyepoxy-based, polyurethane-acrylate-based, polyester acrylate-based, polyepoxyacrylate-based and silicone-based UV curable resin. A method for producing artificial leather, which is formed by An artificial leather produced by the method for producing an artificial leather according to any one of claims 1 to 4, comprising:
Artificial leather comprising a fabric, a resin skin layer, and a ventilation part. An artificial leather produced by the method for producing artificial leather according to claim 5, comprising:
Artificial leather comprising a fabric, a resin skin layer, and a ventilation part.

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