KR101816392B1

KR101816392B1 - Artificial leather for vehicle interior material and method for manufacturing the same

Info

Publication number: KR101816392B1
Application number: KR1020160052678A
Authority: KR
Inventors: 민철희; 정용배
Original assignee: (주)엘지하우시스
Priority date: 2016-04-29
Filing date: 2016-04-29
Publication date: 2018-01-08
Also published as: WO2017188722A1; KR20170123431A

Abstract

An artificial leather for automobile interior material excellent in surface physical properties and cushioning feeling.
The artificial leather for an automobile interior material according to the present invention comprises a single layer; A foam layer formed on the monolayer; A label layer formed on the foam layer; And an aqueous surface treatment layer formed on the label layer, wherein an emboss pattern is formed on the surface of the aqueous surface treatment layer.

Description

TECHNICAL FIELD [0001] The present invention relates to an artificial leather for automobile interior materials and a method of manufacturing the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to an artificial leather for automobile interior materials having excellent physical properties and a method for producing the same.

Artificial leather occupies a large part of the inside of a car. In recent years, studies on artificial leather for automobile interior materials have been actively carried out in order to secure a clean environment and a property not harmful to human body.

Artificial leather is generally produced from polyvinyl chloride (PVC) or polyurethane (PU).

Artificial leather made of PVC is manufactured by laminating a PVC foam layer and a PVC label layer on a single layer by a calendar method and then foaming at a temperature of about 200 캜. However, there is a problem that it is difficult to provide an artificial leather excellent in abrasion resistance and surface physical property only with a PVC material.

Artificial leather made of PU is manufactured by laminating an adhesive layer and a PU marking layer on a single layer by a casting method and then drying. PU material is difficult to foam, and artificial leather having a cushion feeling There is a problem that it is difficult to provide.

Therefore, artificial leather excellent in abrasion resistance and cushioning feeling is required.

A background art related to the present invention is Korean Patent Registration No. 10-0873655 (registered on December 05, 2008), which discloses an artificial leather foamed with flame retardant pigment and a method for producing the same.

It is an object of the present invention to provide an artificial leather for automobile interior material excellent in surface property and cushion feeling.

Another object of the present invention is to provide a method for producing the artificial leather.

According to an aspect of the present invention, there is provided an artificial leather for an automobile interior material, A foam layer formed on the monolayer; A label layer formed on the foam layer; And an aqueous surface treatment layer formed on the label layer, wherein an emboss pattern is formed on the surface of the aqueous surface treatment layer.

The label layer may be formed from a label layer composition comprising a polyurethane (PU) based resin.

The label layer may be formed by a rotary screen process.

The foam layer may be formed from a foam layer composition comprising a polyvinyl chloride (PVC) resin and a blowing agent.

The foam layer composition may contain 5 to 10 parts by weight of a foaming agent per 100 parts by weight of the polyvinyl chloride resin.

The thickness of the foam layer may be 0.2 to 0.4 mm.

The thickness of the label layer may be 50 to 100 mu m.

Wherein the aqueous surface treatment layer comprises a polyurethane (PU) based resin; A curing agent comprising at least one of an isocyanate group and a carbodiimide group; And an aqueous solvent comprising at least one of water and an alcohol.

The monolayer may be a woven or nonwoven fabric comprising at least one of cotton, nylon, polyester and rayon.

(A) A foam layer composition comprising a polyvinyl chloride (PVC) resin and a foaming agent is used to produce artificial leather for automobile interior materials according to the present invention. Forming a foam layer to produce a sheet; (b) forming a label layer on the sheet by a rotary screen process using a label layer composition comprising a polyurethane (PU) based resin; (c) forming an aqueous surface treatment layer on the label layer; And (d) forming an emboss pattern on the surface of the aqueous surface treatment layer.

The foam layer of step (a) may be foamed at a temperature of 220 to 230 ° C.

The calendering step of step (a) may be performed using a roller having a temperature of 100 to 200 ° C.

The aqueous surface treatment layer of step (c) may be formed by performing a gravure coating process.

The emboss pattern of step (d) may be formed by performing a vacuum embossing process.

The vacuum embossing process may be performed under a vacuum of 0.04 to 0.07 MPa (vacuum gauge).

The vacuum embossing process may be performed at a temperature of 160 to 180 ° C.

The artificial leather for automobile interior material according to the present invention has an excellent cushioning feel compared to artificial leather made only of conventional PVC or PU material by the laminated structure of the PVC foam layer and the PU marking layer.

Further, by forming the aqueous surface treatment layer on the PU marking layer, surface physical properties such as abrasion resistance and tactile feel can be improved.

In the present invention, a label layer containing a PU material can be formed on a foam layer containing a PVC material without using an adhesive layer using a rotary screen process. Accordingly, the emboss pattern can be directly formed by the vacuum embossing process without using the release paper.

In addition, the method of manufacturing artificial leather for automobile interior materials of the present invention improves productivity and workability by a calendering process, a rotary screen process, and a gravure coating process.

1 is a sectional view of an artificial leather for an automobile interior material according to the present invention.
2 is a flowchart showing a method for manufacturing artificial leather for automobile interior materials according to the present invention.
3 shows a process flow diagram of a rotary screen according to the present invention.
4 is a photograph of a cross-section of an artificial leather foam layer for an automobile interior material according to Example 1 of the present invention.
Fig. 5 is a photograph of a product (a) containing a normal monolayer according to the present invention and a product (b) comprising a monolayer having a folded wrinkle.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an artificial leather for an automobile interior material according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Leather used for automotive interiors is divided into natural leather and artificial leather. Because natural leather is expensive and inefficient, artificial leather usage is increasing. As mentioned above, artificial leather is generally made of PVC or PU material. Artificial leather made of PVC has a disadvantage that wear resistance is weak and artificial leather made of PU material has a problem that the feeling of cushion is deteriorated due to lowering of foamability.

The present invention provides an artificial leather for an automobile interior material having excellent cushion feeling and durability through a construction including a foam layer containing a PVC material and a label layer including a PU material. In addition, the artificial leather of the present invention has an effect of forming an aqueous surface treatment layer and an emboss pattern on the uppermost portion of artificial leather, and thus having excellent surface physical properties.

In the present invention, the PVC foam layer refers to a foam layer containing a PVC material, and the PU label layer refers to a label layer including a PU material.

1 is a sectional view of an artificial leather for an automobile interior material according to the present invention. An artificial leather for an automobile interior material according to the present invention comprises an artificial layer (10); A foam layer (20) formed on the monolayer; A label layer (30) formed on the foam layer; And an aqueous surface treatment layer (40) formed on the label layer, wherein an emboss pattern is formed on the surface of the aqueous surface treatment layer.

It is preferable that the far-end layer 10 is a portion which is in contact with the car seat frame side and has a constant thickness, high dimensional stability, and is not deformed by heat and pressure for securing rigidity. The monolayer 10 may be a woven or nonwoven fabric including at least one of cotton, nylon, polyester, and rayon.

The foam layer 20 may be formed from a foam layer composition comprising a polyvinyl chloride (PVC) resin and a foaming agent. The foam layer 20 can be formed by mixing a polyvinyl chloride resin and a foaming agent to prepare a foam layer composition, applying the composition to a predetermined thickness and foaming it at about 220 to 230 ° C. The foam layer composition may include a polyvinylidene chloride (PVDC) resin, a chlorinated polyvinyl chloride (CPVC) resin and the like in addition to the polyvinyl chloride resin. On the other hand, in the case of artificial leather made of a PU material, the adhesive layer and the PU label layer are laminated on the monolayer, followed by foaming and drying. The thickness of the PU marking layer is as thin as 30 to 70 탆, and thus, the probability of occurrence of pores on the product surface during foaming is high. Therefore, artificial leather made of PU material is difficult to foam, and it is difficult to provide artificial leather having a cushion feeling

The foaming agent may be at least one selected from the group consisting of azodicarbonamide (ADCA), p, p'-oxybis (benzenesulfonyl hydrazide), p-toluenesulfonylhydrazide (p- toluenesulfonyl hydrazide, sodium bicarbonate, and the like, but are not limited thereto. The foaming agent may have a volume increase rate of 100 to 500% by volume after foaming at about 220 to 230 ° C. In the process of foaming, gas generated from the foaming agent may form bubbles and foam cells may be formed in the foam layer 20. [ The foamed cell may be a sphere-shaped foamed cell, and may be formed as a closed pore wall, and may be referred to as a closed pore or a closed pore, which is not connected to other pores. Since the shape of the foamed cell is not deformed by a physical external force, the soft characteristic and cushioning property of the foamed layer 20 can be improved.

The foam layer composition may contain 5 to 10 parts by weight of a foaming agent per 100 parts by weight of the polyvinyl chloride resin. When the foaming agent is contained in an amount of less than 5 parts by weight, the ductility and cushioning feeling of the artificial leather may be deteriorated. On the other hand, when the amount is more than 10 parts by weight, foamed cells of the foamed layer are excessively produced, resulting in deterioration of surface physical properties and durability.

The foam layer composition may further include a plasticizer and a heat stabilizer to control the melt strength at the time of foaming.

The thickness of the foam layer formed through the foaming process may be 0.2 to 0.4 mm.

If the thickness of the foam layer is less than 0.2 mm, the cushion feeling of the artificial leather may be deteriorated because the thickness is thin, and the pattern of the woven single layer woven fabric may be exposed on the product surface. On the contrary, when the thickness exceeds 0.4 mm, there is a problem that the surface of the product is wrinkled. When the artificial leather is folded for a long time, the shape of the foaming cell is deformed and fixed, which means that deep wrinkles are formed as shown in Fig. 5 (b). Such folding wrinkles are not restored even by heat or steam treatment.

The label layer 30 can be formed from a label layer composition including a polyurethane (PU) based resin, which serves to secure surface smoothness and provide hue. The polyurethane resin may be prepared by polymerizing a polycarbonate diol, a polyether diol or a diol containing a carboxy group, and a diisocyanate compound at about 80 to 100 캜. The prepared polyurethane resin does not contain a volatile organic compound such as toluene, so that it is easily dispersed in water, has no adverse effect on the human body, and is environmentally friendly. Therefore, the label layer 30 has an excellent compatibility with the aqueous surface treatment layer 40 described later, and has an advantage of improving surface physical properties such as tactile sensation.

The thickness of the label layer 30 may be 50 to 100 mu m. If the thickness of the cover layer 30 is less than 50 탆, it may be difficult to secure surface smoothness. If the thickness exceeds 100 탆, the cushioning feeling of the artificial leather may be deteriorated or the adhesive force with the foam layer may be decreased.

The aqueous surface treatment layer (40) improves scratch resistance, stain resistance and surface properties, and provides an environmentally friendly effect. The aqueous surface treatment layer (40) comprises a polyurethane resin; A curing agent comprising at least one of an isocyanate group and a carbodiimide group; And an aqueous solvent comprising at least one of water and an alcohol.

The polyurethane resin contained in the water-based coating composition may be the same as the polyurethane resin of the label layer 30, as described above. The curing agent containing an isocyanate group includes toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, naphthalene diisocyanate, and the like. The curing agent comprising the carbodiimide group may be selected from the group consisting of 1-ethyl-3- (3-dimethylamino) propyl) carbodiimide . The aqueous solvent may be a solvent as opposed to an organic solvent, and may mean a solvent having an OH group. The water-based coating composition may contain an aqueous solvent such as water or an alcohol to improve stain resistance.

An emboss pattern (not shown) is formed on the surface of the aqueous surface treatment layer. The emboss pattern imparts excellent surface texture to artificial leather for automobile interior materials and improves surface durability.

2 is a flowchart showing a method for manufacturing artificial leather for automobile interior materials according to the present invention.

(S110), a label layer forming step (S120), an aqueous surface treatment layer forming step (S130), and an emboss pattern forming step (S140) are performed on the monolayer, .

A foam layer formation step (S110) on the raw monolayer,

After the monolayer 10 is provided, a calendar process is performed to form a foam layer 20 on the monolayer 10 to produce a sheet. At this time, the foam layer 20 is formed from a foam layer composition comprising a polyvinyl chloride (PVC) resin and a foaming agent.

The calendering process includes passing the raw material between the rollers rotating in the opposite direction and performing roller pressing followed by a cooling process. In the calendering process, the raw material may be kneaded at a temperature of 100 to 200 DEG C before passing the raw material between the rollers, but the present invention is not limited thereto.

For example, a foam layer composition may be passed through a calender roller to form a prefoamed layer on the arcuate layer (10). The calender roller is maintained at a temperature of approximately 100 to 200 DEG C, and the average rotation speed of the calender roller may be 30 to 100 m / min. When the temperature of the calender roller is less than 100 캜, the foam layer composition is not sufficiently melted. On the other hand, when the temperature is higher than 200 ° C, shear strength is generated between the calender rollers, resulting in adhesion or early foaming of the foam layer composition on the roller surface.

The prefoamed layer is foamed at a temperature of 220 to 230 ° C to form a foamed layer (20). If the foaming temperature is less than 220 캜, heat transfer of the foam layer may be insufficient and foamability may be lowered. When the foaming temperature is higher than 230 ° C, over-foaming phenomenon may occur, and bubbles may be formed on the surface of the product, and wrinkles may occur on the surface of the product. The monolayer 10 and the foam layer 20 are then cooled to room temperature to produce a semi-finished sheet.

In the label layer formation step (S120)

And a rotary screen process is performed to form a label layer 30 on the sheet. At this time, the label layer is formed from a label layer composition containing a polyurethane (PU) based resin.

The rotary screen process is a process in which a raw material is charged into a screen net, and then the screen net is rotated to coat the raw material on the sheet. More specifically, referring to FIG. 3, color reservoirs and screen rollers can be used to form different colors and patterns on a single layer, such as fibers, fabrics, and the like.

For example, the semi-finished product sheet is injected into a rotary screen device, and then a polyurethane resin is applied on the sheet by a rotating screen roller to form a label layer. At this time, the liquid polyurethane (PU) resin stored in the material reservoir is supplied to the screen rollers. The raw material reservoir may be at least one, and a polyurethane resin is injected into the first raw material reservoir, a separate raw material capable of imparting color to the second raw material reservoir is injected, and then the screen roller connected to each reservoir is rotated To form a label layer having a hue.

In addition to the rotary screen process, a printing method such as a comma coating may be applied, but it is preferable to apply a rotary screen process to secure the surface smoothness of the label layer 30. [ As such, when a rotary screen process is performed, a label layer containing a PU material can be formed on a foam layer containing a PVC material without requiring an adhesive layer. In the present invention, the release paper is used to form the emboss pattern. However, in the present invention, the emboss pattern can be directly formed by the vacuum embossing process without using the release paper by forming the label layer including the PU material by performing the rotary screen process .

The aqueous surface treatment layer formation step (S130)

A gravure coating process is performed to form an aqueous surface treatment layer 40 on the label layer 30. [

The gravure coating process may include a direct gravure coating, a reverse gravure coating, an offset gravure coating, and the like. A direct gravure coating is one in which the coating is performed on a substrate between a roller formed of elastic rubber and a roller containing a coating liquid, and the rotation speed of these rollers may be the same. Also, the direction of rotation of the substrate and the rollers may be reversed. The reverse gravure coating can reverse the direction of rotation of the substrate and the rollers, and the amount of coating can be adjusted by adjusting the speed of the roller. The offset gravure coating allows each roller to be driven independently of one another and to form a coating layer evenly in small amounts by high speed.

The water-based coating composition is as described above. By forming the aqueous surface treatment layer 40, the artificial leather of the present invention can improve scratch resistance, stain resistance, and provide environment-friendly effects.

In the emboss pattern formation step (S140)

An emboss pattern (not shown) is formed on the surface of the aqueous surface treatment layer 40. The emboss pattern can be formed by performing a vacuum embossing process. The vacuum embossing process is a method of transferring embossed patterns by sucking artificial leather under a pressure of vacuum of 0.04 to 0.07 MPa (vacuum gauge). When the vacuum embossing process is performed at less than 0.04 MPa, it is difficult to form an emboss pattern and the cushion feeling may be deteriorated. On the contrary, when it is carried out in excess of 0.07 MPa, the aqueous surface treatment layer 40 may be damaged or surface properties may be deteriorated.

In addition, the vacuum embossing process may be performed at a temperature of 160 to 180 ° C.

If it is carried out at a temperature lower than 160 ° C, it is difficult to sufficiently form an emboss pattern. If the heat treatment is carried out at a temperature higher than 180 ° C, the surface properties of the artificial leather may become rough or torn due to high temperature.

Conventionally, in order to form an emboss pattern, a concave / convex pattern is printed with a roller. However, this method has a limitation in providing an artificial leather having excellent surface physical properties. In the present invention, by increasing the cushion feel and softness by the above-mentioned vacuum embossing process, the surface properties such as tactile feeling can be improved.

INDUSTRIAL APPLICABILITY As described above, the artificial leather for automobile interior material of the present invention has excellent surface smoothness and can form a uniform layer through a production process such as a calendering process or a rotary screen process. Further, through the laminated structure including the PVC foam layer, the PU marking layer and the aqueous surface treatment layer, there is an effect of excellent thickness property of the artificial leather and excellent physical properties of the surface.

The artificial leather for automobile interior material and the manufacturing method thereof will be described in detail as follows.

1. Manufacture of artificial leather for automobile interior materials

Example 1

The nonwoven fabric made of the fabric material including the surface was cut to a thickness of 0.6 mm to provide a monolayer. A calender step was carried out to form a prefoamed layer on the monolayer, and the prefoamed layer was foamed at a temperature of 220 DEG C to form a foamed layer having a thickness of 0.3 mm. The foam layer was formed from a foam layer composition containing 5 parts by weight of azodicarbonamide as a foaming agent, based on 100 parts by weight of polyvinyl chloride resin.

Subsequently, a polyurethane resin was applied on the foam layer by a screen roller rotating by a rotary screen process to form a label layer.

Next, a water-based coating composition comprising a polyurethane resin, toluene diisocyanate as a curing agent, and water as an aqueous solvent was prepared. A gravure coating process was carried out using this, and an aqueous surface treatment layer having a thickness of 20 탆 was formed on the above-mentioned label layer.

Subsequently, a vacuum embossing process was performed at a pressure of 0.06 MPa and a pressure of 170 at the resultant surface of the aqueous surface treatment layer to form an emboss pattern on the surface of the aqueous surface treatment layer, Artificial leather was produced.

Comparative Example 1

A layered product in which a prefoamed layer formed from a foamed layer composition containing polyvinyl chloride resin, a label layer from polyvinyl chloride resin, and an aqueous surface treatment layer were laminated on the monolayer through a calender process. Next, artificial leather for automobile interior materials was manufactured in the same manner as in Example 1, except that the laminate was foamed at a temperature of 220 and then subjected to a vacuum embossing process.

Comparative Example 2

A layered product in which an adhesive layer, a prefoamed layer formed from a foam layer composition containing a polyurethane resin, and an aqueous surface treatment layer were laminated on the monolayer through a calender process. Subsequently, the laminate was foamed at a temperature of 220 ° C., a foam layer having a thickness of 50 μm was formed, and a roll press process was carried out under a pressure of 4 MPa using an embossed embossing roll. Artificial leather for automobile interior material was produced in the same manner as in Example 1. [

Comparative Example 3

Artificial leather for automobile interior materials was prepared in the same manner as in Example 1, except that a comma coating was performed to form a label layer.

2. Property evaluation method and result

Measurement of surface smoothness of the label layer: When the surface of the label layer is smooth or cracked, it is described as "excellent ", and when the surface of the label layer is not smooth or ripped, it is described as" normal ".

Measurement of softness: The softness was measured at a temperature of 23 ± 2 ° C and a relative humidity of 50 ± 5% using a softness measuring instrument (manufacturer, ST300D). Specifically, the softness can be measured by preparing five test pieces having a pi (pi) with respect to the synthetic leather for an automobile interior material, and reading the numerical value of the scale for 15 seconds by pressing the test piece with the ST300D device.

Whether pore / crease on the surface of the product occurred: When the pore and crease were 10% or less on the surface of the product, it was indicated as "None".

[Table 1]

Referring to [Table 1] and FIG. 4, it can be seen that the artificial leather for automobile interior material manufactured according to Example 1 exhibits excellent cushioning due to high ductility by forming foam cells in the foam layer. In addition, it can be seen that embossing (not shown) is formed on the surface of the aqueous surface treatment layer by performing the vacuum embossing process in Example 1, whereby an excellent surface texture and surface durability are formed in the artificial leather. In addition, in the case of Comparative Example 3 in which the label layer was not performed with a rotary screen but was performed with a comma coating, the surface of the label layer was not smooth and ripping occurred.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is to be understood that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

10: Single layer
20: foam layer
30: Cover layer
40: aqueous surface treatment layer
S110: Formation of foam layer on the monolayer
S120: Cover layer formation
S130: Formation of aqueous surface treatment layer
S140: Emboss formation

Claims

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(a) forming a foamed layer on a monolayer by a calendar process using a foam layer composition comprising a polyvinyl chloride (PVC) resin and a foaming agent to produce a sheet;
(b) forming a label layer on the sheet by a rotary screen process using a label layer composition comprising a polyurethane (PU) based resin;
(c) forming an aqueous surface treatment layer on the label layer; And
(d) forming an emboss pattern on the surface of the aqueous surface treatment layer,
Wherein the emboss pattern of step (d) is formed by performing a vacuum embossing process under a pressure of 0.04 to 0.07 MPa (Vacuum gauge).

11. The method of claim 10,
Wherein the foam layer of step (a) is formed by foaming at a temperature of 220 to 230 ° C.

11. The method of claim 10,
Wherein the calendering step of step (a) is performed using a roller having a temperature of 100 to 200 ° C.

11. The method of claim 10,
Wherein the aqueous surface treatment layer of step (c) is formed by performing a gravure coating process.

11. The method of claim 10,
Wherein the thickness of the label layer in step (b) is 50 to 100 占 퐉.

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11. The method of claim 10,
Wherein the vacuum embossing step is performed at a temperature of 160 to 180 ° C.