KR101402783B1 - Synthetic leather and preparing method thereof - Google Patents

Abstract

The present invention relates to an artificial leather, and more particularly, to an artificial leather which is produced by microfibrillating a long-fiber type high-density nonwoven fabric and then using it as a fiber substrate layer for artificial leather and forming uniform and minute pores on the surface of the fiber base layer It relates to artificial leather.
The artificial leather of the present invention can be used as a substitute for natural leather products for footwear and furniture, because it has significantly improved sensibility, chemical resistance, hydrolysis resistance, tearing strength, The present invention relates to an artificial leather product which is high in performance and high quality and which is particularly suitable for use in a vehicle interior decoration agent.

Description

TECHNICAL FIELD [0001] The present invention relates to a synthetic leather and a preparation method thereof,

The present invention relates to a process for producing artificial leather, which is produced by using a long-fiber type high-density micro-fiber nonwoven fabric as a fiber substrate and forming uniform and fine pores on the surface of a long-fiber type high-density micro-fiber nonwoven fabric. More particularly, the present invention relates to a nonwoven fabric comprising a urethane porous layer having a structure having a strong binding force on a long-fiber type high-density microcellular nonwoven fabric. The urethane porous layer is superior in texture, volume, hydrolysis resistance, chemical resistance, It is possible to provide a high-quality, high-performance artificial leather product improved in the appearance and the like.

The process of general artificial leather is performed by applying a urea skin resin compounding liquid containing an organic solvent such as dimethylformamide (DMF), methyl ethyl ketone (MEK) or the like onto a release paper and drying it to form a film, Followed by crosslinking and curing, followed by foaming with a single-fiber microfiber nonwoven fabric or fabric fiber substrate. However, since only a skin coating layer is formed on a fiber base material such as a short fiber nonwoven fabric or fabric having a relatively small density, the sensibility such as touch feeling and volume feeling is considerably lower than that of natural leather, and mechanical properties such as tear strength, sewing strength and tensile strength And thus there is a limit in replacing natural leather. Therefore, it is urgently required to develop artificial leather excellent in mechanical properties and durability, while exhibiting sensitivity similar to that of natural leather, such as volume feeling and touch.

The conventional technique for producing a high-density nonwoven fabric is to prepare a nonwoven fabric by using a high-shear fiber material, that is, a high-shear polyester short fiber or polyvinyl alcohol (PVA) fiber, and then densify the nonwoven fabric by using hot water or steam And a method of increasing the density by using an organic solvent. Korean Patent Laid-Open Publication No. 1997-0043453 discloses a method for producing a three-dimensionally entangled nonwoven fabric by needle punching a high-shear-shrinkable composite fiber, followed by dry heat shrinkage and steam treatment, followed by calendering to increase the density. Korean Patent Publication No. 2003-0055475 Disclosed is a method of dividing fibers by a dividing process in a nonwoven fabric manufacturing process using high shrinkable composite staple fibers and densifying the fibers by hot water or dry heat treatment. According to Korean Patent No. 10-0490249, 10 to 40% by weight of polyvinyl alcohol fibers are incorporated into the microfine composite fibers to prepare a nonwoven web, which is then combined with a high-shrinkage reinforcing fiber to produce a nonwoven fabric, A method for implementing the method is disclosed. However, according to the above-mentioned inventions, it is difficult to increase the density by using a high-shear fiber raw material or by adding a high-shear fiber raw material over a certain weight of the total weight. Can not. In particular, the nonwoven fabric produced by the above invention relaxes the structure contracted by friction or tensile force in the post-processing step such as reduction after shrinkage, and the fabric density after the actual processing is remarkably reduced.

In addition, conventional artificial leather has a disadvantage in that emotional aspects such as volume feeling and touch feeling are remarkably lower than those of natural leather because only skin coating layer is formed on the fiber base material. Although a wet silver layer can be formed on the surface of the fiber substrate in order to complement the emotional surface, the conventional resin for silver layer coating generally does not satisfy the property of hydrolysis resistance, heat resistance, chemical resistance and mechanical properties for automotive interior trimmers .

As a result of efforts for solving the above problems, unlike conventional artificial leather systems, a long-fiber type high-density micro-nonwoven fabric is utilized as a fiber substrate, and a urethane porous layer having excellent hydrolysis resistance, chemical resistance, rigidity and cohesion It is possible to provide artificial leather of high performance and high quality. Thus, the present invention has been completed.

In order to solve the above problems, the present invention relates to artificial leather, which comprises a fiber base layer 101 containing a long-fiber type high-density micro-fiber nonwoven fabric; A urethane porous layer (102) having fine pores; And a skin layer 104 are stacked in this order.

The present invention also relates to the artificial leather, comprising the steps of: forming a long fibrous high-density microfine nonwoven fabric as a fibrous base layer; Forming a urethane porous layer having micropores on one surface of the fiber substrate layer; And forming a skin layer on one surface of the urethane porous layer; The interior material of the automobile can be manufactured through a process including the steps of:

The present invention also relates to an automobile interior material including the artificial leather.

The artificial leather of the present invention has a density of 0.35 g / cm < ³ >, which is different from that of short fibers, even after the weight reduction process because of the dense nature of the long fibers by using a long fiber type high density micro- The tear strength, the sewing strength and the like are much better than those of the conventional products. In addition, since uniform urethane pores are formed on the surface of the long-fiber type high-density nonwoven fabric, excellent sensitivity and sensibility such as volume and touch are obtained, and excellent physical properties such as tensile properties, heat aging resistance, hydrolysis resistance and flame retardancy, It is possible to provide artificial leather of high performance and high quality which can be used for shoes, furniture and the like.

FIG. 1 is a photograph of a cut face of artificial leather of the present invention prepared in Example 1 by scanning electron microscope (SEM).
Fig. 2 is a photograph of the cut surface of the artificial leather produced in Comparative Example 1 taken by a scanning electron microscope (SEM). Fig.

Hereinafter, the present invention will be described in detail.

The present invention relates to a nonwoven fabric which does not require a high shrinkage fiber raw material such as a high shrinkage polyester staple fiber or a polyvinyl alcohol (PVA) fiber, A long fiber type nonwoven fabric capable of exhibiting high density was utilized as a fiber substrate.

The present invention also includes a urethane porous layer using a polyurethane. The polyurethane is composed of two phases in the polymer, that is, a hard segment (HS) and a soft segment (SS) The HS functioning as a crystalline structure exists in a form dispersed in the SS domain. The physical properties and rigidity of polyurethane vary not only with the cohesive strength of HS but also with the type of SS. Mechanical properties, thermal properties, hydrolysis resistance, chemical resistance, and the like depend on the type of polyol used as SS. To this end, the present invention has introduced a urethane porous layer excellent in mechanical properties by precisely controlling and designing rigidity and cohesive force, excellent in hydrolysis resistance and heat resistance by reacting isocyanate with a polyol mixture composed of polyol and chain extender .

As shown in Fig. 1, the artificial leather of the present invention comprises a fiber base layer 101 containing a long-fiber type high-density microfine nonwoven fabric; A urethane porous layer (102) having fine pores; And a skin layer 104 are laminated in this order. In addition, the artificial leather of the present invention may further include an adhesive layer 103 between the urethane porous layer and the skin layer.

The long-fiber type high-density micro-fiber non-woven fabric of the fiber base layer includes at least one general-purpose filament yarn selected from the group consisting of polyester (PET), polyethylene terephthalate (PET) and nylon (PA) PET / PA (Polyethylene terephthalate / Polyamide), PET / PLA (Polyethylene terephthalate / Polylactic acid), PET / Co-PET (Polyethylene terephthalate / Co-Polyethylene terephthalate) and PA / Co- Marine-type or split-type filament yarns comprising at least one selected; May be used.

The long-fiber type high-density micro-fabric non-woven fabric may be a long-fibrous nonwoven fabric in which two or more composite processes selected from the group consisting of spun bond, needle punching and spun lace techniques are continuous and combined. In the present invention, the spun bond / needle punching / Since the lace-filament type nonwoven fabric is arranged in a continuous fashion, unlike the single-filament type nonwoven fabric, in particular, the nonwoven fabric itself has an apparent density of 0.35 g / cm ³ or more, Density of 0.35 g / cm < ³ > to 0.8 g / cm ^3, more preferably a bar having a 0.4 ~ 0.5 g / cm ^3, Is much higher than that of the conventional needle punching nonwoven fabric. Particularly, in the present invention, since the long fiber-type high-density micro-fiber nonwoven fabric can be densified without a separate shrinking process, it has an advantage that it can be impregnated with a water-dispersible polyurethane having no impregnation process or a low concentration. The above-mentioned long-fiber type high-density micro-fabric nonwoven fabric having such characteristics has a higher strength and density than the short-fiber type high-density nonwoven fabric according to the conventional method and is suitable for use as a fiber base material of artificial leather.

The long fibrous high density microfine nonwoven fabric of the fibrous substrate layer has a tensile strength of 40 to 60 kgf / inch (MD) and a CD (cross rotation) of 50 to 60 kgf / inch when measured according to the ASTM 5035 method, The tensile strength may be between MD 42 to 50 kgf / inch and CD 52 to 58 kgf / inch. The long-fiber type high-density micro-fiber non-woven fabric has an elongation (elongation) of 60 to 80% and a CD of 100 to 140% as measured according to the ASTM 5035 method, preferably an elongation of 65 to 75% 130%. The long-fiber type high-density micro-nonwoven fabric preferably has a tear strength of 5.5 to 6.0 kgf and a CD of 5.2 to 5.8 kfg, preferably a tear strength of 5.5 to 5.9 kgf and a CD 5.3 to 5.7 kfg.

As shown in FIG. 1, the urethane porous layer of the artificial leather of the present invention has uniform micropores. The urethane porous layer may include a urethane porous layer composition comprising a polyurethane resin, a solvent, a urethane pore regulator, and a toner in a weight ratio of 100: 30 to 60: 0.5 to 2: 0.1 to 1: 5 to 15, Can be formed by coating on one surface.

In the urethane porous layer composition, the solvent may include at least one selected from the group consisting of dimethylformamide (DMF), ethyl acetate, tetrahydrofuran, ethylene glycol monoethyl ether, and ethylene glycol monoethyl ether acetate And is preferably used in a weight ratio of 100: 30 to 60, preferably 100: 35 to 45, based on the polyurethane resin. If the ratio is less than 30 parts by weight, the viscosity of the solution is too high to form uniform pores. If the ratio is more than 60 parts by weight, the viscosity of the solution is too low to precisely control the thickness.

In the urethane porous layer composition, the urethane porous regulator is used to form uniform pores in the urethane porous layer, and it is preferable that the urethane porous regulator is at least one selected from the group consisting of an anion-based urethane porosity regulator and a nonion- Can be used. The amount of the polyurethane resin to be used is preferably 100: 0.5 to 2 by weight, more preferably 100: 0.5 to 1.5: 1 by weight. If the amount is less than 0.5% by weight, sufficient pores may not be formed in the urethane porous layer , And the pore size may be uneven. Therefore, it is preferable to use within the above range.

In the urethane porous layer composition, the toner is a pigment which imparts the hue of the urethane porous layer. The amount of the toner used is 100: 5 to 15: 1 by weight, preferably 100: 7 to 12: If it is less than 5 parts by weight, it may be difficult to realize the color, and it may exceed 15 parts by weight and may deteriorate various physical properties of the product.

Further, in the urethane porous layer composition, the polyurethane resin may include a polyol, a chain extender, a solvent, and a diisocyanate.

The polyol may include three kinds of polyols such as a polyester-based polyol (weight average molecular weight: 1,000 to 6,000), a polyether-based polyol (weight average molecular weight: 1,000 to 6,000), and a polycarbonate-based polyol . When the polyol is used, the polyester polyol, the polyether polyol and the polycarbonate polyol are used in a weight ratio of 10 to 60:20 to 80: 5 to 60, preferably 20 to 40:30 to 65:20 to 50 Is preferable in terms of hydrolysis resistance and chemical resistance.

The polyol may further include one or more flame retardant polyols such as a reaction type phosphoric acid ester polyol and a polyether ester polyol which do not generate noxious gas during the production of urethane and have excellent flame retardant effect, It is possible to form the urethane porous layer so as to have a good flame retardant performance without any additional step of separately adding the flame retardant by adjusting the urethane structure.

The chain extender may be a conventional one used in the art, and is not particularly limited. However, it is preferable to use a low molecular weight diol having an even number of repeating units, which is advantageous for increasing the degree of crystallization. Specifically, ethylene glycol, propylene Glycol, 1,4-butanediol, 1,6-hexanediol, and methylpentanediol. The amount of the chain extender is preferably 1 to 15 parts by weight, preferably 2 to 10 parts by weight, relative to 100 parts by weight of the polyol. If the amount is less than 1 part by weight, heat resistance and adhesion may be poor. If it is used in an amount of more than 15 parts by weight, unreacted chain extender will occur in an excessively large amount.

The solvent used in the polyurethane resin may be a solvent commonly used in the art, and is not particularly limited, but is preferably dimethylformamide (DMF), ethyl acetate, tetrahydrofuran, ethylene glycol monoethyl ether, Ethylene glycol monoethyl ether acetate, and ethylene glycol monoethyl ether acetate. The amount of the solvent to be used is preferably 150 to 350 parts by weight, preferably 200 to 300 parts by weight, more preferably 250 to 300 parts by weight, based on 100 parts by weight of the polyol. When the amount is less than 150 parts by weight, There may be a problem that it is difficult to increase the molecular weight, and when it is used in excess of 350 parts by weight, it may be difficult to synthesize a resin having a proper viscosity and molecular weight because of low viscosity.

The diisocyanate may be any of those generally used in the art, and includes, but is not limited to, 4,4-diphenylmethane diisocyanate (MDI), modified MDI, hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), can comprise at least one member selected from the group consisting of dicyclohexylmethane diisocyanate (H ₁₂ MDI) and xylylene diisocyanate (XDI). The amount of the diisocyanate to be used is preferably such that the NCO / OH ratio of the polyol and the diisocyanate is 0.95 to 1.05, preferably 1.0.

The polyurethane resin may further include at least one selected from a yellowing inhibitor, an antioxidant, a surfactant, and a blocking agent.

The yellowing inhibitor may be selected from those generally used in the art and may be selected from phenolic-formamidine-based, benzophenone-based, and benzotriazole (benzotriazole) It is better to use more than species.

The antioxidant may be a conventional one used in the art, and includes, but is not limited to, amines, hindered phenols, phosphites, and thioesters. It is preferable to use at least one selected from among them.

The urethane pore regulator (surfactant) may be any of those generally used in the art, and is not particularly limited, but it is preferable to use at least one selected from anion-based and nonion-based surfactants.

The blocking agent may be any one generally used in the art, and is not particularly limited, but it is preferable to use at least one selected from methanol and ethanol.

The urethane porous layer constituting the artificial leather of the present invention has a modulus of 60 to 80 kgf / cm ² , preferably 60 to 75 kgf / cm < ² >. The urethane porous layer has a tensile strength in the range of 370 to 420 kgf / cm ² in the width direction (W, width, 橫) and 410 to 450 kgf / cm ^{2 in the} length direction (L, length, cm ² , and may preferably be 380 to 400 kgf / cm ² in the width direction (W) and 420 to 440 kgf / cm ^{2 in the} longitudinal direction (L). The urethane porous layer has an elongation of 430 to 480% in the transverse direction (W) measured according to JIS K7311, And a longitudinal direction (L) of 400 to 450% Preferably 440 to 480% in the width direction (W) And a longitudinal direction (L) of 410 to 440% Lt; / RTI >

In the artificial leather of the present invention, the skin layer may be formed on one surface of the urethane porous layer by coating and / or curing the skin coating composition. The skin coating composition may further include a polyurethane resin, a solvent, and a dispersing agent, and may further include at least one additive selected from a yellowing agent, an antioxidant, and a leveling agent.

In the artificial leather of the present invention, the adhesive layer may be a general adhesive used in the art, and it is not particularly limited, but it is preferable to use a urethane adhesive agent, preferably a phosphorus- Use of a liquid type urethane adhesive is preferable in that it can impart flame retardancy to artificial leather.

The artificial leather of the present invention is in the form of a three-layered laminate of a fibrous base layer, a urethane porous layer and a skin layer, or a four-layered laminate of a fibrous base layer, a urethane porous layer, an adhesive layer and a skin layer.

In the artificial leather of the present invention, the fibrous base layer has an average thickness of 0.7 to 1.3 mm, the urethane porous layer having the micropores has an average thickness of 0.1 to 0.4 mm, the skin layer has an average thickness of 0.05 to 0.3 mm .

In the artificial leather of the present invention, when measured according to MS 300-31, the static load elongation can be 20 to 30% in the width direction (W, width, 橫) and 8 to 10% in the longitudinal direction (L, length, 있으며) , Preferably 24 to 28% in the width direction (W) and 8.5 to 9.5% in the longitudinal direction (L).

Further, the artificial leather of the present invention may have a residual denseness of 15 to 20% in the width direction (W, width, 橫) and 4 to 6% in the lengthwise direction (L, ) 17 to 19% and the longitudinal direction (L) 4 to 6%.

The method of producing artificial leather according to the present invention comprises the steps of: forming a long fibrous high-density microfine nonwoven fabric as a fibrous base layer; Forming a urethane porous layer having micropores on one surface of the fiber substrate layer; And forming a skin layer on one surface of the urethane porous layer.

In addition, in the method for producing artificial leather of the present invention, the nonwoven fabric produced by the composite process by the spun bond, needle punching and / or spun lace process may be made finer by the weight reduction process Can be manufactured.

The step of forming the skin layer may be performed by coating the urethane porous layer with a skin coating composition on one surface of the urethane porous layer.

The step of forming the skin layer may include forming an adhesive layer on one surface of the urethane porous layer, and then forming a skin layer on one surface of the adhesive layer.

In addition, the step of forming the skin layer may include forming an adhesive layer on one surface of the skin layer in which the skin coating composition is cured in a sheet or film form; And a step of fabricating a fibrous substrate layer on which the urethane porous layer is formed and a skin layer on which the adhesive layer is formed. Further, the composite can be laminated such that the adhesive layer and the urethane porous layer are in contact with each other.

The artificial leather of the present invention as described above has excellent emotional aspects such as volume and touch, and has excellent physical properties such as sewing strength, tensile strength and elongation, and can be used for various purposes such as shoes and furniture, It is very suitable for use as a built-in agent.

Hereinafter, preferred comparative examples and examples are provided to facilitate understanding of the present invention. However, the following examples are provided to further illustrate the present invention, and the present invention is not limited to the following examples.

[Example]

Fabrication of nonwoven fabric for textile base layer

Comparative Preparation Example 1

A fabric having a fineness of 1.4 denier, a fiber length of 51 mm, a fiber fineness of 2 denier, and a fiber length of 51 mm nylon (PA) of 50% were produced by a conventional method of producing a needle punching nonwoven fabric and shrunk by 230 g / m ² Thereafter, the weight loss was performed for 30 minutes in a 3% NaOH aqueous solution to prepare a nonwoven fabric for a fiber substrate layer. The results of the properties are shown in Table 1.

division Before contraction After contraction After weight loss Weight (g / m ² ) 230 310 248 Thickness (mm) 1.06 1.03 0.98 Density (g / cm ³⁾ 0.21 0.30 0.25 Cotton shrinkage (%) 28

As shown in Table 1, the density of the nonwoven fabric increases by 41.9% at 0.21 g / cm ³ to 0.30 g / cm ³ after shrinkage treatment. Also, the surface contraction ratio due to shrinkage in the longitudinal and transverse directions is shown to be shrunk by 28%. It is difficult to exhibit a density of 0.3 g / cm < ³ > or more even if the density is increased by shrinking. Also, after the weight loss, the fiber is partially damaged and the density is decreased by 0.25 g / cm ³ .

Preparation Example 1

Fineness 3 deniers, even type (PET / Co-PET, 70/30 , 25 islands) the long-fiber-type high-density micro-fiber non-woven fabric by the filament yarns in a spunbond / spunlaced composite continuous process width 1950mm, average weight 450g / m ^2, and And an average thickness of 1.13 mm, and subjected to a weight reduction process in a 3% NaOH aqueous solution for 30 minutes as in Comparative Preparation Example 1 to prepare a long-fiber microfine nonwoven fabric. In the following Table 2, MD means MACHINE DIRECTION and CD means CROSS DIRECTION.

division Before weight loss After weight loss Weight (g / m ² ) 450 410 Thickness (mm) 1.13 0.98 Density (g / cm ³⁾ 0.40 0.42 The tensile strength
(kgf / inch) MD 45.0 44.5 CD 55.5 55.0 Shindo
(%) MD 87 70 CD 96 120 Phosphorus strength
(kgf) MD 5.7 5.75 CD 5.5 5.40

As shown in Table 2, the density of the long fiber nonwoven fabric has a very high apparent density (0.4 g / cm ³ ) compared with the density (generally about 0.21 g / cm ³ ) of the general needle punching nonwoven fabric, It can be seen that high-density characteristics are exhibited without going through the process. In the case of long-fiber type nonwoven fabric, since the fiber tends to return to its original shape, even after heat or physical force is applied in a post-process such as weight loss, the density after the weight loss tends to be similar to that before the weight loss so that a stable high density nonwoven fabric can be provided .

Synthesis of urethane porous layer

Comparative Production Example 2

110 parts by weight of a polyester polyol having a molecular weight of 2,000, 50 parts by weight of a polyether polyol, 15 parts by weight of ethylene glycol and 100 parts by weight of DMF (dimethylformamide) were charged into the reaction tank, respectively, After stirring, 80 parts by weight of MDI (4.4-diphenylmethane diisocyanate) was added to the reaction mixture in three portions so as not to cause a rapid reaction, while maintaining the temperature at 80 占 폚 for 6 hours The reaction was carried out so that the NCO / OH ratio of the polyol and the diisocyanate was 1.0, and 1 part by weight of methanol (METHANOL) and 190 parts by weight of DMF (dimethylformamide) were added as a blocking agent at a reaction temperature of 75 캜 or lower, , Confirming that there is no -NCO group and terminating the reaction.

Next, in the course of the reaction, 0.3 part by weight of a yellowing inhibitor and 0.3 parts by weight of an antioxidant were added, respectively, to prepare a general type polyurethane composition for forming a silver layer.

Preparation Example 2-1

16 parts by weight of ethylene glycol, 10 parts by weight of DMF (weight average molecular weight: 2,000), 100 parts by weight of a polyol having a weight average molecular weight of 2,000, a polyether polyol having a weight average molecular weight of 2,000 and a polycarbonate having a weight average molecular weight of 2,000 at a weight ratio of 30: 50: Dimethylformamide) were initially charged into the reaction vessel, and the mixture was stirred for 1 hour while maintaining the temperature at 50 ° C. 90 parts by weight of MDI (4.4-diphenylmethane diisocyanate) And the reaction was carried out. The reaction was carried out so that the NCO / OH ratio of the polyol and the diisocyanate was 1.0 for 6 hours while maintaining the temperature within the range of 80 ° C so as not to be overheated due to the temperature rise due to the reaction heat. When the temperature of the reaction was 70 ° C, , 0.01 part by weight of methanol (METHANOL) and 270 parts by weight of DMF (dimethylformamide) were added to the mixture, and the NCO group was masked. In the reaction, 0.3 parts by weight of each of the yellowing inhibitor and the antioxidant and 0.2 parts by weight of the cell controlling agent were added to prepare a polyurethane resin composition in which the terminal NCO group was blocked.

Preparation Example 2-2

A polyurethane resin composition was prepared in the same manner as in Preparative Example 2-1 except that a polyol having a weight average molecular weight of 2,000, a polyether polyol having a weight average molecular weight of 2,000, and a polycarbonate having a weight average molecular weight of 2,000 at a ratio of 20:30: 50 weight ratio.

Experimental Example 1: Measurement of physical properties of urethane porous layer

The polyurethane resin compositions prepared in Comparative Preparation Example 2, Preparation Example 2-1 and Preparation Example 2-2 were each produced in the form of a sheet having an average thickness of 0.25 mm through wet processing, And the results are shown in Table 3 below.

1. Tensile Properties

The tensile properties of the sheet were measured according to KS M 6782, ASTM D-412 and JIS K7311.

2. Heat aging resistance

The sheet was subjected to a heat resistance test at 100 DEG C for 168 hours based on MS 300-31, and the tensile properties were measured as described above.

3. I hydrolysis

The sheet was immersed in distilled water at 85 캜 according to MS 300-31, heated for 96 hours, taken out and allowed to stand at room temperature for 1 hour, and the tensile properties were measured as described above.

4. Peel strength

A hot melt cloth tape having a width of 25 mm was thermally fused at 130 DEG C for 5 seconds to both sides of the sheet to measure the interlaminar peeling strength of the sheet based on KS M 0533 and JIS K 6854.

In the following Table 3, W means width, L means lengthwise, and L means length.

division Comparative Production Example 2 Preparation Example 2-1 Preparation Example 2-2 Tensile Properties Modulus (Kgf / cm ² ) 55 70 65 The tensile strength
(Kgf / cm ² ) W  350  380 390 L  400 420 430 Elongation (%) W  500 450 470 L  450 420 440 Heat aging resistance
after the test Modulus (Kgf / cm ² ) 48 67 64 The tensile strength
(Kgf / cm ² ) W 270 360 370 L 310 390 400 Elongation (%) W 460 420 450 L 410 410 420 I can
Degradability
after the test Modulus (Kgf / cm ² ) 45 68 64 The tensile strength
(Kgf / cm ² ) W 240 350 360 L 280 380 400 Elongation (%) W 440 430 450 L 400 410 420 Peel strength (Kgf / cm) 2.6 3.0 3.3

As a result of physical properties of the urethane porous sheet shown in Table 3, when the degree of change in physical properties after the hydrolysis resistance test and the heat aging resistance test was compared, Preparation Examples 2-1 and 2-2 of the present invention were compared with Comparative Preparation Example 2 It can be confirmed that it has superior characteristics.

Example 1: Production of artificial leather

(1) The polyurethane resin composition, DMF, urethane pore regulator, surfactant, and TONER prepared in Preparative Example 2-1 were mixed in a ratio of 100:40 : 1: 0.5: 10 by weight, followed by coagulation and washing in an aqueous solution of DMF to form a microporous wet urethane porous layer, which is then dried through a thermal tenter to form a fibrous substrate layer- A urethane porous layer laminated sheet was produced.

(2) A skin coating composition was prepared by mixing and stirring a polyurethane resin, a solvent and a dispersing agent, and skin-coating the composition on a release paper to form a skin layer having a thickness of 0.09 mm (based on the thickness after drying) Lt; 0 > C for 5 minutes.

Next, a two-component adhesive having phosphorus and nitrogen-based flame retardant added thereto was coated on the dried skin layer to form an adhesive layer having a thickness of 0.12 mm (based on the thickness after drying), followed by heating at 90 DEG C for 1 minute to cure the adhesive layer To prepare a sheet laminated with an adhesive layer-skin layer-release paper.

Next, the sheet laminated with the adhesive layer-skin layer-release paper and the sheet laminated with the fiber substrate layer-urethane porous layer were laminated so that the adhesive layer and the urethane porous layer were joined together and aged for 48 hours while maintaining the temperature at 80 캜 The releasing paper was peeled off to produce an artificial leather layered with the fibrous base layer-urethane porous layer-adhesive layer-skin layer. Fig. 1 shows a photograph of the cut surface of the manufactured artificial leather.

Example 2

An artificial leather was prepared in the same manner as in Example 1 except that the polyurethane resin composition prepared in Preparation Example 2-2 was used instead of the polyurethane resin composition prepared in Preparation Example 2-1.

Comparative Example 1

After preparing the nonwoven fabric for the fiber substrate layer prepared in Comparative Preparation Example 1, the same skin coating composition as in Example 1 was skin-coated on the release paper to form a skin layer having a thickness of 0.09 mm (based on the thickness after drying) Lt; / RTI >

On the top of the dried skin layer, a two-component adhesive having a nitrogen-based flame retardant added thereto was coated to form an adhesive layer having a thickness of 0.12 mm (based on the thickness after drying), followed by curing by heating at 90 ° C for 1 minute. Then, the non-woven fabric for fiber substrate layer prepared in Comparative Production Example 1 was laminated on the adhesive layer, aged for 48 hours while maintaining the temperature at 80 ° C, and then the release paper was peeled off to obtain an artificial leather having a skin coating layer formed on the single- . Fig. 2 shows a photograph of the cut surface of the manufactured artificial leather.

Experimental Example 2: Measurement of physical properties of artificial leather

The physical properties of the artificial leather prepared in Examples 1 to 2 and Comparative Example 1 were measured by the following methods, and the results are shown in Table 4 below.

1. Static elongation and residual shortening

MS 300-31, a specimen having a width of 50 mm and a length of 250 mm was allowed to stand for 10 minutes under a load of 8 kgf, and the elongation at the constant load and the residual elongation were measured according to the following equations (1) and (2).

[Equation 1]

Static load elongation (%) = L1-100 (where L1 is the distance between the marks after 10 minutes of loading)

&Quot; (2) "

Residual shortening (%) = L2-100 (where L2 is the distance between the marks after 10 minutes after removing the load)

2. Sewing strength

The sewing strength was measured at a tension of 20 mm at the upper and lower portions and at a tension rate of 200 mm / min at the upper and lower portions of the 30 mm clamp, respectively, according to MS 300-31.

3. Flammability

JIS D1201 and KS K0583, "Burning Test Method for Organic Materials in Automobile Indoor Materials", and the evaluation results are shown as flammability, delayed and self-extinguishing, flammability is the burning rate exceeding 100 mm / The retarding property is that the burning rate is 100 mm / min or less, the self-extinguishing property is within 50 mm from the standard line and it is extinguished within 60 seconds.

division Comparative Example 1 Example 1 Example 2 The tensile strength
(kgf / 30 mm) W 61 74 76 L 35 69 70 Elongation (%) W 118 125 128 L 81 98 99 Static Load Elongation (%) W 35 27 25 L 7 9 9 Light fastness (degree) 3 to 4 4 4 Sewing strength (kgf) W 102 143 148 L 71 85 87 Residual Ratio (%) W 23 18 18 L 7 5 5 I hydrolyse Slight discoloration Discoloration, no abnormality Discoloration, no abnormality Flammability (mm / min.) Self-extinguishing Self-extinguishing Self-extinguishing Volume sense, touch △ ◎ ◎ △: Bad feeling such as volume feeling and touch feeling after production
○: Excellent sensibility such as volume feeling and touch after commercialization
◎: Very good emotion such as volume feeling and touch after commercialization

As can be seen from the above Table 4, Examples 1 and 2 of the present invention exhibited excellent characteristics such as sewing strength, tensile strength, elongation and residual reduction as compared with the artificial leather of Comparative Example 1, And it was confirmed that it showed similar tendency to the texture of natural leather.

1, which is artificial leather of Example 1, a urethane porous layer having uniform and fine pores formed on the surface of the fiber base layer of the long-fiber type high-density micro-fiber nonwoven fabric can be confirmed. The density of the fiber base layer is high, It is confirmed that the pore layer is formed to enable the emotional expression such as excellent volume feeling and touch feeling to be achieved.

2, which is a photograph of artificial leather of Comparative Example 1 of the prior art, is composed of only a skin layer having no pore layer on a short fiber type microfine fiber substrate having a relatively low density, It is confirmed that the sewing strength and tear strength are lowered.

Although the preferred embodiments of the artificial leather according to the present invention have been described above, the scope of the present invention is not limited to the above-described embodiments and the following claims. Those skilled in the art will appreciate that, Various modifications and equivalent embodiments are possible.

101: long fiber type high density microfine fiber base layer
102: Urethane pore layer
103: Adhesive layer
104: Skin layer
201: Short fiber type microfiber fiber substrate
202: adhesive layer
203: skin layer

Claims (18)

A fibrous substrate layer 101 containing a long fibrous high density microfine nonwoven fabric; A urethane porous layer (102) having fine pores; And a skin layer (104) are laminated in this order.
The method according to claim 1,
And an adhesive layer (103) between the urethane porous layer and the skin layer.
The nonwoven fabric according to claim 1, wherein the long-fiber type high-density micro-
And an apparent density of 0.35 to 0.8 g / cm < ³ >.
The nonwoven fabric according to claim 3, wherein the long-fiber type high-density micro-
According to the ASTM 5035 method, the tensile strength is 40 to 60 kgf / inch for MD (machine direction) and 50 to 60 kgf / inch for CD (crossing)
According to the ASTM 5035 method, the elongation is 60 to 80% of MD and 100 to 140% of CD,
Characterized in that the tear strength measured in accordance with ASTM 5035 method is between MD 5.5 to 6.0 kgf / cm and CD 5.2 to 5.8 kfg / cm.
The nonwoven fabric according to claim 3, wherein the long-fiber type high-density micro-
Filament yarns containing at least one selected from PET (Polyethylene terephthalate) and PA (Polyamide); And
PET / PA (Polyethylene terephthalate / Polyamide), PET / PLA (Polyethylene terephthalate / Polylactic acid), PET / Co-PET (Polyethylene terephthalate / Co-Polyethylene terephthalate) and PA / Co- Marine-type or split-type filament yarns containing at least one selected;
And at least one filament yarn selected from the group consisting of filament yarns.
The method of claim 1, wherein the urethane porous layer
A polyurethane resin, a solvent, a urethane pore regulator and a toner in a weight ratio of 100: 30 to 60: 0.5 to 2: 5 to 15. The polyurethane resin composition according to claim 6, wherein the polyurethane resin
A polyol containing a polyester-based polyol (weight average molecular weight: 1,000 to 6,000), a polyether-based polyol (weight average molecular weight: 1,000 to 6,000) and a polycarbonate-based polyol (weight average molecular weight: 1,000 to 6,000);
Chain extenders containing at least one selected from ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol and methylpentanediol;
A solvent containing at least one selected from the group consisting of dimethylformamide (DMF), ethyl acetate, tetrahydrofuran, ethylene glycol monoethyl ether and ethylene glycol monoethyl ether acetate;
4,4-diphenylmethane diisocyanate (MDI), modified MDI, hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (H ₁₂ MDI) and xylylene diisocyanate (XDI) A diisocyanate containing at least one selected from the group consisting of:
Wherein the synthetic leather is a synthetic leather.
8. The method of claim 7, wherein the polyol
Wherein the flame retardant polyol further comprises at least one flame retardant polyol selected from the group consisting of reactive phosphoric acid ester polyol and polyether ester polyol.
The artificial leather according to claim 7, wherein the polyol comprises a polyester polyol, a polyether polyol and a polycarbonate polyol in a weight ratio of 10: 60: 20 to 80: 5: 60.
The artificial leather according to claim 7, wherein 1 to 15 parts by weight of a chain extender and 150 to 350 parts by weight of a solvent are added to 100 parts by weight of the polyol.
8. The polyurethane resin composition according to claim 7, wherein the polyurethane resin
An anti-yellowing agent, an antioxidant, a surfactant, and a blocking agent.
The urethane porous layer according to claim 1, wherein the urethane porous layer has a modulus of 60 to 80 kgf / cm ² when measured according to KS M 6782, and a tensile strength of 370 (W, width) when measured according to ASTM D- ~ 420 kgf / cm ^2, and the longitudinal direction (L, length) 410 ~ 450 is kgf / cm ^2, on the basis of JIS K7311 direction of elongation as measured width (W, width) 430 ~ 480 % And length direction (L, length) 400 to 450% By weight.
The artificial leather according to claim 1, wherein the skin layer comprises a skin coating composition containing a polyurethane resin, a solvent and a dispersing agent.
[Claim 3] The method according to claim 1, wherein the fibrous substrate layer has an average thickness of 0.7 to 1.3 mm, the urethane porous layer having micropores has an average thickness of 0.1 to 0.4 mm, and the skin layer has an average thickness of 0.05 to 0.3 mm Artificial leather.
The artificial leather according to any one of claims 1 to 14,
In the measurement according to MS 300-31, the static load elongation is 20 to 30% in the width direction (W, width) and 8 to 10% in the longitudinal direction (L, length) To 20% and a length direction (L, length) of 4 to 6%.
Forming a long fibrous high density microfine nonwoven fabric as the fibrous base layer;
Forming a urethane porous layer having micropores on one surface of the fiber substrate layer; And
Forming a skin layer on one surface of the urethane porous layer;
The method of manufacturing a synthetic leather according to claim 1,
[17] The nonwoven fabric according to claim 16, wherein the nonwoven fabric produced by the composite process of at least two selected from the group consisting of spunbond, needle punching and spun lace process is miniaturized through a weight reduction process, Gt;
17. The method of claim 16, wherein forming the skin layer comprises:
Forming an adhesive layer on one surface of a skin layer that is cured in the form of a sheet or film; And
And a skin layer on which the urethane porous layer is formed and the adhesive layer,
Wherein the foam is foamed so that the adhesive layer and the urethane porous layer are in contact with each other.

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