KR101030314B1 - Artificial leather - Google Patents

Abstract

The present invention relates to a vehicle artificial leather having excellent surface feel and occupant support, wherein the polymer elastic body is impregnated in a nonwoven fabric in which microfibers having a single yarn fineness of 0.001 to 0.3 denier are entangled with each other, and the microfine fibers are napped on the surface thereof. It is characterized by having a structure that forms the moor, and having a specific coefficient of friction coefficient.

The present invention has an appropriate friction coefficient characteristic and excellent surface feel and excellent occupant support (occupant holding property) that prevents the occupant from slipping in one direction during cornering.

Artificial leather, vehicle, car, surface feel, occupant, bearing capacity, holding property, coefficient of friction

Description

Artificial Leather {Artificial leather}

The present invention relates to an artificial leather for a vehicle having excellent surface feel and occupant support. More specifically, the present invention relates to a vehicle artificial leather having an appropriate friction coefficient characteristic, which provides excellent surface feel and prevents the rider from slipping in one direction during cornering. The present invention relates to a vehicle artificial leather having excellent occupant holding properties.

Artificial leather is composed of a nonwoven fabric in which microfibers are intertwined three-dimensionally and a polymer elastomer impregnated in the nonwoven fabric. The artificial leather has excellent feel, light effect and drape, and has a soft texture and unique appearance similar to that of natural leather. BACKGROUND ART It is widely used as a sheet skin material or interior material of a vehicle (hereinafter, referred to as "vehicle") for transportation such as trains and ships.

Artificial leather (hereinafter referred to as "vehicle artificial leather"), which is used as a vehicle material, requires durability and form stability against friction and external forces, and has excellent surface feel and prevents the passenger from slipping to one side when cornering. Bearing capacity (passenger holding) is required at the same time. In addition, recently, the artificial leather material is recognized as a highly sensitive material, and the application to the vehicle is increasing day by day, and the aesthetic elements such as luxurious sensitivity and soft lighting effect are becoming very important.

In the prior art of manufacturing artificial leather, Korean Patent No. 0178049 discloses a bundle of polyamide microfiber fibers having a single yarn fineness of 0.1 decitex or less impregnated with a polymer elastomer in an woven fabric, and then dyed and brushed to feel and light. It shows how to make artificial leather with excellent effect.

In addition, Japanese Laid-Open Patent Publication No. 2005-264408 discloses a method for producing artificial leather using microfine fibers made of polytrimethylene terephthalate instead of microfine fibers made of polyamide or polyethylene terephthalate to improve the surface feel. .

The conventional methods have a problem in that the surface touch of the artificial leather and the occupant support force (hereinafter, referred to as the "occupant support force") that suppress the tilting phenomenon in which the occupant slides to one side when cornering the car cannot be improved at the same time.

In the case of car artificial leather used as a skin material of a car seat or an interior material of a car, if the lighting effect effect is too excellent, a messy feeling appears, and the luxury feeling is rather unfavorable.

If there are too many lighting effects of car artificial leather and the friction coefficient is high, the occupant's support is improved, but the occupant feels tight contact and lacks slippery. do.

On the contrary, when the lighting effect of the artificial leather for the vehicle is too small and the friction coefficient is lowered, the surface feel is improved, but the occupant bearing capacity is significantly lowered.

The present invention is to provide a vehicle artificial leather having excellent occupant support (occupant holding property) to provide excellent surface feel and to prevent the rider from slipping in one direction when cornering.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

First, a vehicle artificial leather according to the present invention has a structure in which a polymer elastic body is impregnated in a nonwoven fabric in which microfibers having a single yarn fineness of 0.001 to 0.3 denier are entangled with each other, and the microfibers are formed on the surface to form wool. And a coefficient of friction characteristic that satisfies all the conditions of the following general formulas (I) to (IV).

[In formulas (I) to (IV), a is a forward static friction coefficient measured in the same direction as the parent's hair growth direction, and b is a reverse static friction coefficient measured in a direction opposite to the parent's hair growth direction. , c is the forward kinetic coefficient of friction in the same direction as the cow's mouth direction, and d is the reverse kinetic coefficient measured in the opposite direction to the parent's hair direction]

If the friction coefficient characteristic is out of the range of the general formulas (I) to (IV), the surface feel may be lowered and the rider may feel unpleasant, and the occupant's support force (holding property) is lowered, so that the occupant slips to the Han Chinese when cornering. Tension may occur.

The polymer elastomer is a polyurethane resin, a polyurea resin, or the like, and a polyurethane resin is most preferable in view of workability.

The ultrafine fibers are polyamide fibers, polyester fibers, and the like, but the present invention does not specifically limit the kind of ultrafine fibers.

Single yarn fineness of the ultrafine fibers is 0.001 ~ 0.3 denier.

If the single yarn fineness is less than 0.001 denier, the strength of the artificial leather is lowered. If the single yarn fineness is more than 0.3 denier, the touch and lighting effect of the artificial leather is lowered.

In the present invention, various physical properties of artificial leather for vehicles are evaluated by the following method.

Friction coefficient characteristics

Friction coefficients of the forward and reverse coefficients measured in the same direction as the mouth's mouth direction and the reverse forward and reverse coefficients measured in the opposite direction to the mouth's mouth direction are friction products from To Yo Seik. Measure using a coefficient tester.

Regardless of the type of friction coefficient to be measured, a sample (vehicle artificial leather) is always attached to the upper friction material of the friction coefficient tester so that the direction of the moor is in the opposite direction to the machine progress direction (reverse direction).

On the other hand, when measuring the forward static friction coefficient and the forward dynamic friction coefficient, the sample (vehicle artificial leather) is attached to the lower friction material of the friction coefficient tester so that the direction of the moor is the same direction (forward direction) as the machine progress direction.

On the contrary, when measuring the reverse static friction coefficient and the reverse dynamic friction coefficient, the sample (vehicle artificial leather) is attached to the lower friction material of the friction coefficient tester so that the direction of the moor is in the opposite direction to the machine progress direction (reverse direction).

Next, the moving distance of the lower friction material, which is the friction material, is about 20 cm, 200 g of the weight (weight), the load cell is 1 kg, and the chart scale is X1. After measuring the coefficient of friction three times, these measurements are averaged to give the final coefficient of friction.

The reverse static friction coefficient and the forward static friction coefficient are the values showing the maximum static frictional force, and the reverse dynamic friction coefficient and the reverse dynamic friction coefficient are the median values of the start value and the end value as the friction coefficient decreases to the sustained force as the friction material moves. To be taken.

Next, an example of a method of manufacturing the vehicle artificial leather according to the present invention will be described in detail.

First, in the present invention, the island-in-the-sea composite fiber composed of sea component which is an alkali-soluble copolyester and island components having a single yarn fineness of 0.001 to 0.3 denier is dispersed in the sea component, and then opened, carded, cross-wrapped and Needle punching produces a nonwoven fabric.

Next, the composite sheet impregnated with the polymer elastic body in the nonwoven fabric and then treated with an aqueous alkali solution to elute the sea component to the composite sheet impregnated with the polymer elastic body in the nonwoven fabric intertwined microfibers having a single yarn fineness of 0.001 ~ 0.3 denier Manufacture.

Meanwhile, in the present invention, the nonwoven fabric prepared as described above may be first treated with an aqueous alkali solution to elute the sea component, and then impregnated with the polymer elastomer.

Alkali-soluble copolyester as the sea component has polyethylene terephthalate as a main component, and is an additional component with a molecular weight of 400 to 20000, most preferably 1000 to 4000 polyethylene glycol, polypropylene glycol, 1,4-cyclohexanedicar Acids, 1,4-cyclohexanedimethanol, 1,4-cyclohexanedicarboxylate, 2,2-dimethyl-1,3-propanediol, 2,2-dimethyl-1,4-butanediol, 2, 2,4-trimethyl 1,3-propanediol and copolyester obtained by copolymerizing 25% by weight or less of one or two or more selected from adipic acid.

Polyurethane resins, polyurea resins, polyacrylic acid resins, and the like may be used as the polymer elastomer, but a polyurethane resin is preferable in terms of processed tablets, abrasion resistance, hydrolysis resistance, and the like.

The weight ratio of the fibrous base composed of the polymer elastomer / microfiber is preferably 10/90 to 90/10.

When the weight ratio of the polymer elastomer is less than 10% by weight, the cushioning property is too low, and when it exceeds 90% by weight, the feel and light effect are too low.

The method of filling the polymer elastomer may be applied by wet coagulation or dry coagulation after impregnating and / or applying the organic solvent solution or the aqueous dispersion of the polymer elastomer to the nonwoven fabric.

As an organic solvent of a high molecular elastic body, toluene, acetone, methyl ethyl ketone, etc. other than polar solvents, such as dimethylformamide, dimethylacetamide, and dimethyl sulfoxide, can be used.

Next, buffing at least one time in the direction and the direction of the hair of the wool to buff one or more times in the reverse direction to the hair of the cow again to form a composite sheet prepared as described above and impregnated with a polymer elastic body impregnated in the microfiber nonwoven fabric Manufacture artificial leather with wool on the surface.

In the buffing, the amount of grinding per buffing is 0.1 mm or less.

When the amount of grinding exceeds 0.1 mm, surface irregularities become uneven and the surface feel worsens.

Grinding amount is expressed as the thickness of the fabric after buffing based on the thickness of the fabric, and can be measured with an online or portable thickness meter.

Next, a silicone-based softener is applied to the surface of the artificial leather and selectively dyed to manufacture a vehicle artificial leather.

As a method of imparting the silicone resin solution to the artificial leather surface, a padding method, a spray method, a coating method using a gravure roll, and the like may be used.

In the present invention, the step of repeating the buffing in the forward and reverse directions as described above, the step of adjusting the amount of grinding per buffing to 0.1mm or less, and the step of imparting a silicone-based softener to the artificial leather surface, Only some of these processes may be carried out.

The artificial leather for a vehicle of the present invention described above has an appropriate friction coefficient characteristic to provide excellent surface feel and excellent occupant support (occupant holding property) to prevent the occupant from slipping in one direction during cornering.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

However, the present invention is not limited by the following examples.

Example  One

The island-in-the-sea composite fiber (single-fiber fineness: 0.05 denier of the island component) composed of the sea component of the alkali-soluble copolyester and 70 island components of the polyester resin dispersed and dispersed in the sea component is cut to a length of 50 mm to form short fibers. After the lamination web of the islands-in-the-sea composite short fibers was manufactured through a carding and cross wrapper process, needle punching was performed to prepare a nonwoven fabric of the island-in-the-sea composite fiber.

Next, the prepared nonwoven fabric was impregnated with 40% by weight of the polyurethane resin relative to the weight of the nonwoven fabric and then wet coagulated, and the aqueous solution was dissolved in an aqueous alkali solution (caustic soda solution) to elute the sea component in the island-in-the-sea composite fiber. Was prepared.

Next, using a brush, buff once in such a way that the amount of grinding is 0.08 mm in the hair growth direction and the forward direction of the cows to form the composite sheet, and then grind in the opposite direction (the reverse direction of the hairs of the cows to be formed). Repeating the buffing process three times so that the amount is 0.08㎜ to form a wool on the surface, and then dyed to manufacture a vehicle artificial leather.

The results of evaluating various physical properties of the manufactured vehicle artificial leather are shown in Table 1.

Example  2

Vehicle artificial leather was manufactured in the same manner as in Example 1, except that a silicone softener was sprayed on the surface of the artificial leather on which the wool was formed.

The results of evaluating various physical properties of the manufactured vehicle artificial leather are shown in Table 1.

Comparative Example  One

The island-in-the-sea composite fiber (single-fiber fineness: 0.05 denier of the island component) consisting of the sea component of the alkali-soluble co-polyester and 70 polyester components dispersed and arranged in the sea component is also cut to a length of 50 mm to form short fibers. After the lamination web of the islands-in-the-sea composite short fibers was manufactured through a carding and cross wrapper process, needle punching was performed to prepare a nonwoven fabric of the island-in-the-sea composite fiber.

Next, the prepared nonwoven fabric was impregnated with 40% by weight of the polyurethane resin to the nonwoven fabric, and then wet coagulated. Prepared.

Next, using a brush to buff the cow three times in the hair direction and the normal direction to form the composite sheet to form the wool on the surface and dyed it to manufacture a vehicle artificial leather.

In the buffing, the amount of grinding per buffing was 0.15 mm.

The results of evaluating various physical properties of the manufactured vehicle artificial leather are shown in Table 1.

division Example 1 Example 2 Example 3




Coefficient of friction
characteristic



Forward static friction coefficient (a) 1.58 1.70 1.60 Reverse Static Friction Coefficient (b) 2.15 2.05 2.50 Forward dynamic friction coefficient (c) 1.38 1.60 1.40 Reverse dynamic friction coefficient (d) 2.05 1.85 2.24

1.865
1.875
2.050

1.715
1.725
1.82 Emotional
Properties Surface texture Great Great Bad Occupant support Great Great Great

In Table 1, the emotional properties were classified as excellent by evaluating that 8 or more out of 10 were good through sensory tests of 10 experts, by supplementing when 5-7 were good, and poor by 4 or less by good.

The present invention has an appropriate friction coefficient characteristic and excellent surface feel and excellent occupant support (occupant holding property) to prevent the occupant from slipping in one direction during cornering.

Claims (2)

The microfibers having a single yarn fineness of 0.001 to 0.3 denier are impregnated with a polymer elastic body in a nonwoven fabric interwoven with each other, and the microfine fibers are formed on the surface of the microfibers to form a wool, and the following general formulas (I) to general Artificial leather, characterized by having a coefficient of friction properties that satisfy all the conditions of the formula (IV).

[In formulas (I) to (IV), a is a forward static friction coefficient measured in the same direction as the parent's hair growth direction, and b is a reverse static friction coefficient measured in a direction opposite to the parent's hair growth direction. , c is the forward kinetic coefficient of friction in the same direction as the cow's mouth direction, and d is the reverse kinetic coefficient measured in the opposite direction to the parent's hair direction] The artificial leather according to claim 1, wherein the polymer elastomer is one selected from a polyurethane resin and a polyurea resin.