(19)
(11)EP 2 623 655 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
17.06.2020 Bulletin 2020/25

(21)Application number: 11829542.7

(22)Date of filing:  27.09.2011
(51)International Patent Classification (IPC): 
D06N 3/00(2006.01)
D04H 1/4382(2012.01)
D04H 1/435(2012.01)
D04H 1/541(2012.01)
(86)International application number:
PCT/KR2011/007091
(87)International publication number:
WO 2012/044036 (05.04.2012 Gazette  2012/14)

(54)

ARTIFICIAL LEATHER AND METHOD FOR MANUFACTURING SAME

KUNSTLEDER UND VERFAHREN ZU SEINER HERSTELLUNG

CUIR ARTIFICIEL ET SON PROCÉDÉ DE FABRICATION


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 29.09.2010 KR 20100094743

(43)Date of publication of application:
07.08.2013 Bulletin 2013/32

(73)Proprietor: Kolon Industries, Inc.
Seoul 07793 (KR)

(72)Inventors:
  • LEE, Eung Min
    Gimhae-si Gyeongsangnam-do 621-060 (KR)
  • JUNG, Jong Suc
    Daegu 704-360 (KR)
  • HWANG, Yeong Nam
    Gumi-si Gyeongsangbuk-do 730-747 (KR)
  • PARK, Jong Ho
    Gumi-si Gyeongsangbuk-do 730-030 (KR)

(74)Representative: Ter Meer Steinmeister & Partner 
Patentanwälte mbB Nymphenburger Straße 4
80335 München
80335 München (DE)


(56)References cited: : 
EP-A2- 1 302 587
KR-A- 20090 058 202
US-B2- 7 132 024
JP-A- S58 214 589
KR-B1- 100 951 976
  
  • DATABASE WPI Week 200124 Thomson Scientific, London, GB; AN 2001-229992 XP002767488, -& JP 2001 032140 A (KURARAY CO LTD) 6 February 2001 (2001-02-06)
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

[Technical Field]



[0001] The present invention relates to an artificial leather and a method for manufacturing the same. More specifically, the present invention relates to an artificial leather useful as an alternative to natural leather and a method for manufacturing the same.

[Background Art]



[0002] An artificial leather is manufactured by impregnating a polymeric elastomer in a non-woven fabric comprising three-dimensionally entangled ultrafine fibers, which is widely utilized in a variety of applications such as shoes, clothes, gloves, miscellaneous goods, furniture and automobile interior materials due to natural leather-like soft texture and unique appearance.

[0003] EP 1 302 587 A2, discloses a process for the preparation of microfibrous non-woven fabric with good mechanical and dyeing properties comprising the following stages of a) preparation of a microfiber constituted in general from polyesters used singularly or in mixtures between them or with nylons 6, nylons 6.6 or other materials normally used in the textile field, b) preparation, by means of needle-punching, of a felt comprising the microfiber indicated above, c) impregnation of the felt with polymer binder, d) mechanical treatment in order to generate the suede effect, e) dyeing of the non-woven fabric, in which a polyester constituted partially or totally from repeating monomer units of trimethylene terephthalate (PTT).

[0004] JP 2001-032140A relates to a multicomponent fiber and a leathery sheet using the fiber, wherein the multicomponent fiber satisfies that a fiber cross section has an island-in-sea structure, the island component is composed of (A) a crystalline polyester and the sea component is composed of a mixture material comprising (C) a dispersion component composed of a crystalline resin and (D) a dispersion component composed of a block copolymer and present in (B) a dispersion medium component composed of an extractable resin, the resin C is a crystalline polyester or a crystalline polyamide, the copolymer D comprises a hard block composed of an aromatic polyester and a soft block composed of an aliphatic polyether, etc., the ratio of the polyester A/[the sum total of the resin C and the copolymer D] is (90/10)-(40/60) (weight ratio), etc.

[0005] Such an artificial leather is manufactured using a variety of fibers such as polyethylene terephthalate fibers and polyamide fibers.

[0006] However, a common artificial leather is made of short fibers containing a single component. Accordingly, the short fibers constituting the artificial leather exhibit similar mechanical physical properties and similar entanglement behaviors. As a result, distance and pores between short fibers are similar. Also, there is a problem of difficulty of realization of an artificial leather having satisfactory texture, fullness and flexibility due to differentiation in terms of interaction between short fibers.

[0007] Meanwhile, in order to impart fullness comparable to natural leather to an artificial leather, a method for increasing a density of a non-woven fabric through a shrinkage process is suggested. In addition, a method for improving flexibility of the artificial leather such as softener or tumbling treatment is suggested.

[0008] However, these methods may deteriorate other properties of an artificial leather such as texture or appearance.

[Disclosure]


[Technical Problem]



[0009] Therefore, the present invention is directed to a method for manufacturing an artificial leather and the artificial leather manufactured by said method capable of preventing problems caused by these limitations and drawbacks of the related art.

[0010] The present invention is conceived in response to demand for a more fundamental method for improving physical properties of artificial leather, such as control of an internal structure of non-woven fabric.

[0011] It is one aspect to provide a method for manufacturing an artificial leather that comprises two or more types of short fibers made of different components, thus exhibiting superior texture, flexibility, breathability and fullness, and enabling great weight reduction.

[0012] It is another aspect to providean artificial leather manufactured by said method and that comprises two or more types of short fibers made of different components, thus exhibiting superior texture, flexibility, breathability and fullness, and enabling considerable weight reduction.

[Technical Solution]



[0013] In accordance with one aspect of the present invention, provided is an artificial leather manufactured by a method as described herein and including: a non-woven fabric containing short fibers having a fineness of 0.00111 to 0.555 dtex (0.001 to 0.5 denier); and a polymeric elastomer impregnated in the non-woven fabric, wherein the short fibers are two or more types of polyester short fibers having different numbers of repeat units of -CH2-.

[0014] In accordance with another aspect of the present invention, provided is a method for manufacturing an artificial leather including: preparing two or more types of island-in-sea conjugate fibers, each comprising a sea component and an island component, wherein island components of the two or more types of island-in-sea conjugate fibers are two or more types of polyester polymers having different numbers of repeat units of -CH2-; forming a non-woven fabric using the two or more types of island-in-sea conjugate fibers; and eluting the sea components from the two or more types of island-in-sea conjugate fibers to form an ultrafine non-woven fabric, wherein a temperature of the hot roller is maintained within a range of 80 to 200°C, and,
the artificial leather has a recovery rate of 80% or more.

[0015] The general description described above and the following detailed description are provided only for exemplification and illustration of the present invention and should be construed as providing more detailed description of claims.

[Advantageous Effects]



[0016] The present invention has the following effects.

[0017] The artificial leather according to the present invention comprises two or more types of polyester short fibers having different elastic recovery. Short fibers having relatively high elastic recovery form a spring-like structure during an entanglement process for forming a non-woven fabric.

[0018] The artificial leather of the present invention has pores exhibiting superior compressive elasticity (in a thickness direction) and being uniformly formed to have a predetermined size, as compared to an artificial leather only comprising polyethylene terephthalate (two repeat units of -CH2-) short fibers, since it partially comprises the spring-like structure. Accordingly, the present invention provides an artificial leather that has superior texture, flexibility, breathability and fullness and enables considerable reduction in weight.

[0019] Furthermore, this spring structure makes surface naps upright, enabling production of an artificial leather in which the difference in friction coefficient according to nap direction is minimized, as compared to a common artificial leather in which naps lie in one direction. Accordingly, the artificial leather of the present invention can reduce displeasure caused by the difference in friction property according to the nap direction.

[0020] Meanwhile, when a non-woven fabric was formed using only polyester short fibers having three or more repeat units (-CH2-), an interior spring-like structure is readily formed, but entanglement between short fibers is difficult, a density and mechanical strength of the non-woven fabric are deteriorated, and an artificial leather satisfying appearance, texture and physical properties required for artificial leather manufacture companies cannot be produced.

[0021] In addition, the non-woven fabric according to the present invention comprises polyester short fibers, thus exhibiting superior adhesiveness to the polymeric elastomer, for example, polyurethane. Accordingly, the artificial leather of the present invention has superior durability.

[0022] The artificial leather having superior physical properties may be widely utilized in a variety of fields such as shoes, clothes, gloves, miscellaneous goods, furniture and vehicle internal materials.

[Best Mode]



[0023] Hereinafter, embodiments of the artificial leather and the method for manufacturing the same according to the present invention will be described in detail.

[0024] The artificial leather of the present invention comprises a non-woven fabric and a polymeric elastomer impregnated in the non-woven fabric.

[0025] The non-woven fabric comprises short fibers having a fineness of 0.00111 to 0.555 dtex (0.001 to 0.5 denier). The non-woven fabric having a fineness satisfying a range defined above has superior texture. When the fineness of the short fibers is lower than 0.00111 dtex (0.001 denier), the texture of the non-woven fabric is good, but it is not easy to manufacture the non-woven fabric and color fastness to washing, indicating a loss level of a dye after washing, may be deteriorated. Meanwhile, when the fineness of the short fibers exceeds 0.555 dtex (0.5 denier), the texture of the non-woven fabric may not be good.

[0026] The fineness of short fibers may be calculated by collecting a sample using gold coating, photographing a cross-section of the sample at a predetermined magnification with a scanning electron microscope (SEM), measuring a diameter of the short fibers and applying the diameter of the short fibers to the following Equation:



wherein π is a circular constant, D is a cross-sectional diameter of short fibers (µm) and ρ is a fiber density (g/cm3).

[0027] The non-woven fabric of the present invention comprises two or more types of polyester short fibers. The two or more types of polyester short fibers have at least one repeat unit of -CH2-. Different types of polyester short fibers have different numbers of repeat units of -CH2-.

[0028] Selectively, the two or more types of polyester short fibers may have two or four repeat units. For example, the non-woven fabric may comprise two or more types of short fibers including polyethylene terephthalate (PET) short fibers, polytrimethylene terephthalate (PTT) short fibers, and polybutylene terephthalate (PBT) short fibers.

[0029] The polyethylene terephthalate short fibers are relatively cheap and exhibit superior tensile strength. In addition, the polyethylene terephthalate short fibers have a high melting point and thus exhibit superior heat resistance. Accordingly, the non-woven fabric of the present invention may requisitely comprise polyethylene terephthalate short fibers which are one of the two or more types of polyester short fibers.

[0030] A content of the polyethylene terephthalate short fibers in the non-woven fabric is 5 to 95% by weight, preferably 10 to 50% by weight. When the content of the polyethylene terephthalate short fibers is lower than 5% by weight, mechanical strength of the non-woven fabric may be deteriorated, and when the content of the polyethylene terephthalate short fibers is higher than 95% by weight, short fibers constituting the non-woven fabric cannot form a dense structure and, as a result, an artificial leather made of the non-woven fabric may exhibit deterioration in texture, flexibility and fullness.

[0031] One of parameters, affecting texture, flexibility and fullness of an artificial leather, is mixing uniformity of short fibers of the non-woven fabric used for manufacture of the artificial leather. According to the present invention, the two or more types of polyester short fibers are uniformly mixed to an extent that the non-woven fabric has an weight variation coefficient (CV%) of 20% or less. When the weight variation coefficient of the non-woven fabric exceeds 20%, texture, flexibility and fullness of the artificial leather made of the non-woven fabric may be deteriorated.

[0032] The weight variation coefficient (CV%) is calculated by collecting samples at various positions of the non-woven fabric, measuring a weight per unit area of the samples, calculating a standard deviation and an arithmetic mean using the measured weight per unit area and obtaining the weight variation coefficient in accordance with the following Equation:



[0033] The different types of polyester short fibers constituting the non-woven fabric of the present invention may have different "elastic recovery at an elongation of 20%".

[0034] In one embodiment of the present invention, maximum and minimum values of "elastic recovery at an elongation of 20%" of different types of short fibers constituting the non-woven fabric of the present invention are present and a ratio of the maximum value to the minimum value is 10 to 80%.

[0035] When the ratio of the maximum value to the minimum value regarding the elastic recovery at an elongation of 20% is within the range defined above, two or more types of short fibers constituting the non-woven fabric may be densely entangled and short fibers having a relatively high elastic recovery may form a spring-like structure. Accordingly, the artificial leather made of a non-woven fabric exhibits superior texture, flexibility and fullness.

[0036] When the ratio of the maximum value to the minimum value regarding the elastic recovery at an elongation of 20% is lower than 10%, two or more types of short fibers constituting the non-woven fabric may be densely entangled, and short fibers having a relatively high elastic recovery may not form a spring-like structure. As a result, texture, flexibility and fullness of the artificial leather may be deteriorated. On the other hand, when the ratio of the maximum value to the minimum value regarding the elastic recovery at an elongation of 20% is higher than 80%, it may not be easy to manufacture a non-woven fabric.

[0037] Owing to the short fibers having a relatively high elastic recovery that form a spring structure, compressive elasticity in a thickness direction of the artificial leather is improved. The compressive elasticity may be represented by compressibility and recovery rate. That is, the artificial leather made of the non-woven fabric according to the present invention has a compressibility (thickness direction) of 8 to 50%. When the compressibility of the artificial leather is lower than 8%, the artificial leather is hard and rigid, and when the compressibility thereof is higher than 50%, texture such as fullness is deteriorated.

[0038] Meanwhile, the recovery rate indicates a level of recovery, when a load is removed after compression. The artificial leather made of the non-woven fabric according to the present invention has a recovery rate of 80% or more. When the recovery rate of the artificial leather is lower than 80%, the artificial leather is deteriorated in shape stability and fullness and cannot exhibit luxury and exclusivity.

[0039] In addition, fibers having a high elastic recovery exhibit superior recovery to an applied exterior power. When the artificial leather comprises fibers having a high elastic recovery, surface nap formed through a grinding process such as a buffing process becomes more upright due to the internal spring structure. Accordingly, a difference in friction coefficient between forward direction (nap direction) and reverse direction on the surface of the artificial leather is considerably reduced, a difference in texture between directions on the surface of the artificial leather is reduced, the difference according to direction is minimized and surface texture can thus be improved. When the difference in friction coefficient between forward and reverse directions is decreased, texture of the artificial leather is superior. In one embodiment of the present invention, the difference in the friction coefficient is 0.30 or less.

[0040] The two or more types of polyester short fibers constituting the non-woven fabric have a length of 5 to 100 mm. When the short fibers satisfying the length range are entangled, manufacture processibility of the non-woven fabric can be improved and the artificial leather made of the non-woven fabric exhibit superior physical properties. When the length of the short fibers is lower than 5 mm, it may be difficult to manufacture the non-woven fabric, and strength and texture of the artificial leather may be deteriorated. Meanwhile, when the length of the short fibers exceeds 10 mm, it may be difficult to manufacture the non-woven fabric.

[0041] The polymeric elastomer impregnated in the non-woven fabric may be polyurethane. Specifically, the polymeric elastomer may be polycarbonatediol, polyesterdiol, polyetherdiol or a mixture thereof. Selectively, the polymeric elastomer is polysiloxane. The polymeric elastomer is not limited to polyurethane or polysiloxane.

[0042] A content of the polymeric elastomer in the artificial leather may be 20 to 30% by weight. When the content of the polymeric elastomer is lower than 20% by weight, the desired elongation cannot be obtained, and when the content of the polymeric elastomer exceeds 30% by weight, the texture of the artificial leather is deteriorated, the artificial leather is readily discolored and an elongation of the artificial leather is also deteriorated.

[0043] The artificial leather of the present invention has an "elastic recovery at an elongation of 10%" of 80% or more. The artificial leather having an elastic recovery of 80% or more can be easily recovered to the original shape although a pressure is applied thereto for a long period of time. Owing to the superior elastic recovery, when the artificial leather of the present invention is applied to products such as shoes, clothes, gloves, miscellaneous goods, furniture and vehicle internal materials, the products are not wrinkled and a natural and luxurious appearance can be realized.

[0044] Next, a method for manufacturing an artificial leather in accordance with one embodiment of the present invention will be described in detail.

[0045] First, two or more types of island-in-sea conjugate fibers comprising a sea component and an island component are prepared. Specifically, a molten solution of a sea component polymer and a molten solution of an island component polymer solution are prepared and a conjugate spinning process is performed using a conjugate spinneret to prepare filaments. Subsequently, the filaments are extended. Crimps are formed on the extended filaments and the crimped filaments are cut to a predetermined length to obtain island-in-sea conjugate fibers having a monofiber shape.

[0046] According to the present invention, island components of the two or more types of island-in-sea conjugate fibers have repeat units of -CH2- and are polyester polymers which have different numbers of the repeat units.

[0047] That is, the first island-in-sea conjugate fibers may comprise the first and second polymers as sea and island components and the second island-in-sea conjugate fibers may comprise first and third polymers as sea and island components. The third island-in-sea conjugate fibers comprising the first and fourth polymers may be further provided as the sea and island components. That is, the first to third island-in-sea conjugate fibers comprise the same polymers as sea components and different polymers as island components. For the subsequent sea component elution process, the first polymer is different from the second to fourth polymers in terms of solubility in solvent.

[0048] For example, the second polymer may be polyethylene terephthalate (PET), the third polymer may be polybutylene terephthalate (PBT), and the fourth polymer may be polytrimethylene terephthalate (PTT).

[0049] Subsequently, a non-woven fabric is formed of the two or more types of island-in-sea conjugate fibers.

[0050] Specifically, the two or more types of island-in-sea conjugate fibers are subjected to opening, blending and carding processes and island-in-sea conjugate fibers having a monofiber shape are homogeneously blended to form webs. Subsequently, the obtained webs are laminated through a cross-lapping process and the laminated webs are combined while the island-in-sea conjugate fibers are entangled by needle punching to prepare a non-woven fabric.

[0051] Optionally, the process of forming webs by blending two or more types of island-in-sea conjugate fibers may be carried out by an air-laid method using an air jet, a wet-laid method in which mixing is performed in water or the like.

[0052] The process of entangling the two or more types of island-in-sea conjugate fibers may also be carried out by rapid fluid treatment, chemical bonding or hot air through.

[0053] The produced non-woven fabric may have a unit weight of 100 to 700 g/m2. A final product manufactured using the non-woven fabric using the unit weight has an optimum density.

[0054] Subsequently, a polymeric elastomer is impregnated in the non-woven fabric.

[0055] For example, a polymeric elastomer solution is prepared and the non-woven fabric is dipped in the polymeric elastomer solution. The polymeric elastomer solution may be prepared by dissolving or dispersing polyurethane in a predetermined solvent. For example, the polymeric elastomer solution may be prepared by dissolving polyurethane in a dimethylformamide (DMF) solvent or dispersing polyurethane in a water solvent. The polymeric elastomer solution may also be prepared by directly using a silicone polymeric elastomer without dissolving or dispersing a polymeric elastomer in a solvent.

[0056] Optionally, a pigment, a light stabilizer, an antioxidant, a flame retardant, a fabric softener, a coloring agent or the like may be added to the polymeric elastomer solution.

[0057] Before the non-woven fabric is dipped in the polymeric elastomer solution, the non-woven fabric is padded with an aqueous polyvinyl alcohol solution to stabilize the shape thereof.

[0058] An amount of the polymeric elastomer impregnated in the non-woven fabric can be controlled by controlling concentration of the polymeric elastomer solution or the like. Taking into consideration the fact that the content of polymeric elastomer finally present in the artificial leather is 20 to 30%, a concentration of the polymeric elastomer solution is preferably within 5 to 20% by weight. Also, the non-woven fabric is preferably dipped in the polymeric elastomer solution for 0.5 to 15 minutes while the temperature of polymeric elastomer solution having a concentration of 5 to 20% by weight is maintained at 10 to 30°C.

[0059] After dipping the non-woven fabric in the polymeric elastomer solution, the polymeric elastomer impregnated in the non-woven fabric is coagulated in a coagulation bath and washed in a washing bath. In the case in which the polymeric elastomer solution is obtained by dissolving polyurethane in a dimethylformamide solvent, the polymeric elastomer is coagulated in the coagulation bath containing a mixture of water and a small amount of dimethylformamide to induce elution of dimethylformamide contained in the non-woven fabric into the coagulation bath. Polyvinyl alcohol padded in the non-woven fabric and remaining dimethylformamide are removed from the non-woven fabric in the washing bath.

[0060] Subsequently, the polymeric elastomer-impregnated non-woven fabric is hot-calendered. The hot-calendaring is carried out by passing the polymeric elastomer-impregnated non-woven fabric through a hot roller to compress the fabric. A temperature of the hot roller is maintained within a range of 80 to 200°C. When the temperature of the hot roller is lower than 80°C, hot calendering effect cannot be sufficiently obtained and when the temperature of the hot roller is higher than 200°C, short fibers of the non-woven fabric surface may be damaged.

[0061] Through the hot calendering process, the polymeric elastomers are rearranged and short fibers of the non-woven fabric surface are homogeneously arranged. As a result, during the subsequent process described below, uniform naps are formed on the surface of the non-woven fabric.

[0062] Subsequently, the sea component is removed from the hot-calendered non-woven fabric. When the sea component is eluted from the two or more types of island-in-sea conjugate fibers constituting the non-woven fabric, only the island component remains and the ultrafine non-woven fabric comprising ultrafine short fibers is formed. The elution process of the sea component may be carried out using an alkali solvent such as aqueous sodium hydroxide solution.

[0063] In the case of the non-woven fabric made of the first to third island-in-sea conjugate fibers, the first polymer which is the sea component is eluted and only the second to fourth polymers remain as island components. As a result, an ultrafine non-woven fabric comprising ultrafine short fibers is formed.

[0064] Optionally, the impregnation of the polymeric elastomer described above may be carried out after the ultrafine process, rather than before the ultrafine process. That is, instead of impregnating the polymeric elastomer in the non-woven fabric before the ultrafine process, the polymeric elastomer may be impregnated in the ultrafine non-woven fabric formed through the ultrafine process.

[0065] Subsequently, the ultrafine non-woven fabric is subjected to a raising process. The raising process forms a great amount of naps on the surface of the non-woven fabric by rubbing the surface of the ultrafine non-woven fabric with a polishing means such as sandpaper.

[0066] Subsequently, the raised non-woven fabric is dyed and then subjected to post-treatment to complete production of the artificial leather.

[0067] The produced artificial leather has a compressibility of 8 to 50% and a recovery rate of 80% or more, and the difference between a friction coefficient in a forward direction (nap direction) and a friction coefficient in a reverse direction on the surface of the artificial leather is 0.30 or less.

[0068] Hereinafter, the present invention will be described in detail with reference to examples and comparative examples. These examples are provided only for better understanding and should not be construed as limiting the scope of the present invention.

Example 1



[0069] Polyethylene terephthalate as an island component and copolymer polyester as a sea component were conjugate-spun to form filaments and the formed filaments were extended, crimped and cut to form first conjugate fibers in the form of short fibers having a fineness of 3.885 dtex (3.5 denier) and a length of 50 mm. A content of polyethylene terephthalate which was the island component of the first conjugate fibers was 70% by weight and a content of the copolymer polyester which was the sea component thereof was 30% by weight.

[0070] In addition, second conjugate fibers in the form of short fibers having a fineness of 4.44 dtex (4.0 denier) and a length of 51 mm were prepared in the same manner as in the first conjugate fibers, except that polytrimethylene terephthalate was used as the island component. The content of polytrimethylene terephthalate which was the island component of the second conjugate fibers was 70% by weight, and the content of the copolymer polyester which was the sea component was 30% by weight.

[0071] Subsequently, after the first conjugate fibers and the second conjugate fibers are supplied at amounts of 90% by weight and 10% by weight, respectively, they are subjected to opening, blending and then carding/cross-lapping processes to form a web laminate and the webs of the laminate were combined through needle punching to produce a non-woven fabric.

[0072] Subsequently, the non-woven fabric was thermally-contracted at a high temperature to increase a density of the non-woven fabric. Subsequently, polyurethane was dissolved in dimethylformamide (DMF) as a solvent to prepare a polyurethane solution having a concentration of 15% by weight, the high-density non-woven fabric was dipped for 8 minutes and the polyurethane was coagulated in an aqueous dimethylformamide solution having a concentration of 25% by weight. The non-woven fabric was washed with 70°C water several times to produce a polyurethane-impregnated non-woven fabric.

[0073] Subsequently, the polyurethane-impregnated non-woven fabric was treated with 10% by weight of a 100°C sodium hydroxide aqueous solution, and only the island component was left by eluting the copolymer polyester as the sea component from the non-woven fabric to produce an ultrafine non-woven fabric.

[0074] Subsequently, the surface of the ultrafine non-woven fabric was buffed using a Roughness No. 240 sandpaper, and dyed in a high-pressure rapid dying machine using a dispersion dye, fixed, washed, dried and treated with a softener and an anti-static agent to obtain an artificial leather.

Example 2



[0075] An artificial leather was manufactured in the same manner as in Example 1, except that the second conjugate fibers were prepared using polybutylene terephthalate as the island component, instead of polytrimethylene terephthalate.

Example 3



[0076] An artificial leather was manufactured in the same manner as in Example 1, except that a non-woven fabric was produced such that the contents of the first conjugate fibers and the second conjugate fibers were 70% by weight and 30% by weight, respectively.

Example 4



[0077] An artificial leather was manufactured in the same manner as in Example 1, except that a non-woven fabric was produced such that the contents of the first conjugate fibers and the second conjugate fibers were 50% by weight and 50% by weight, respectively.

Example 5



[0078] An artificial leather was manufactured in the same manner as in Example 1, except that a non-woven fabric was produced such that the contents of the first conjugate fibers and the second conjugate fibers were 30% by weight and 70% by weight, respectively.

Example 6



[0079] An artificial leather was manufactured in the same manner as in Example 1, except that a non-woven fabric was produced such that the contents of the first conjugate fibers and the second conjugate fibers were 10% by weight and 90% by weight, respectively.

Example 7



[0080] An artificial leather was manufactured in the same manner as in Example 1, except that, in addition to the first and second conjugate fibers, third conjugate fibers comprising 70% by weight of polybutylene terephthalate (island component) and 30% by weight of copolymer polyester (sea component) were further used and a non-woven fabric was produced such that contents of the first to third conjugate fibers were 90%, 5% and 5%.

Example 8



[0081] An artificial leather was manufactured in the same manner as in Example 7, except that a non-woven fabric was produced such that contents of the first to third conjugate fibers were 50%, 25% and 25%.

Example 9



[0082] An artificial leather was manufactured in the same manner as in Example 7, except that a non-woven fabric was produced such that contents of the first to third conjugate fibers were 10%, 60% and 30%.

Example 10



[0083] An artificial leather was manufactured in the same manner as in Example 7, except that a non-woven fabric was produced such that contents of the first to third conjugate fibers were 10%, 30% and 60%.

Comparative Example 1



[0084] An artificial leather was manufactured in the same manner as in Example 1, except that a non-woven fabric was produced using only the first conjugate fibers without the second conjugate fibers.

Comparative Example 2



[0085] An artificial leather was manufactured in the same manner as in Example 1, except that a non-woven fabric was produced using only the second conjugate fibers without the first conjugate fibers.

[0086] Elastic recovery, texture, surface texture, friction property, and compressive elasticity (compressibility and recovery rate) of the artificial leathers manufactured in Examples and Comparative Examples were measured in accordance with the following methods and the results are shown in Table 3 below.

Elastic recovery (%)



[0087] A sample in which a distance of 200 mm was marked was mounted on a tensile tester in which a distance between clamps was 250 mm, elongated to an elongation of 10% at a speed of 50 mm/min and was stood for one minute. Subsequently, the load was removed at the same speed as the tensile strength, the sample was stood for three minutes, an actual distance (x) of the distance marked above was measured and elastic recovery was measured in accordance with the following equation.


Texture



[0088] In order to measure a texture of the artificial leather, an evaluation group including five specialists was formed. Functional tests regarding three items including flexibility, fullness and bending property were performed and evaluation was carried out by grading on a scale of 0 to 5, with 5 being the best. The scores of the respective items were summed, the scores assigned by five specialists were further added and evaluation was carried out in accordance with the following Table 1.
[TABLE 1]
TotalTexture
0∼15 ×
16∼30 Δ
31∼45
46∼60
61∼75

Surface texture



[0089] In order to measure surface texture of the artificial leather, an evaluation group including five specialists was formed. Functional tests regarding three items including flexibility, fullness and bending property were performed and evaluation was carried out by grading on a scale of 0 to 5, with 5 being the best. The scores of the respective items were summed, the scores assigned by five specialists were further added and evaluation was carried out in accordance with the following Table 2:
[TABLE 2]
TotalSurface texture
0∼5 ×
6∼10 Δ
11∼15
16∼20
21∼25

Friction property



[0090] Friction property was evaluated from the difference between a friction coefficient in a forward direction (nap direction) and a friction coefficient in a reverse direction on the surface of the artificial leather and the measurement method is as follows.

[0091] The friction coefficient in the forward direction which is a direction such as nap direction and the friction coefficient in the reverse direction opposite to the nap direction were measured using a friction tester (produced by Toyoseiko Co., Ltd.). Identical test specimens, objects in need of testing, were used as upper and lower friction materials and the upper material was set such that the nap direction thereof was opposite to a movement direction of the friction tester. Meanwhile, the lower friction material was adhered during measurement of friction coefficient in the forward direction such that the friction tester movement direction was equivalent to the nap direction, and the lower friction material was adhered during measurement of friction coefficient in the reverse direction such that the friction tester movement direction was opposite to the nap direction.

[0092] Under conditions including a movement distance of about 20 cm and a balance weight of 200 g of the lower friction material, an object to which a friction force was applied, a load cell of 1 kg and a chart scale of X1, various friction coefficients were measured three times and an average of the obtained measures was calculated to obtain a final friction coefficient value.

[0093] The value of friction coefficient was determined by reading a maximum static frictional force.

[0094] Friction property was determined from an absolute value of the difference between forward friction coefficient and reverse friction coefficient obtained using the friction coefficient value.


Compressive elasticity



[0095] The compressive elasticity (in the thickness direction) of the artificial leather was determined from a compressibility and a recovery rate, and the compressibility and recovery rate of the artificial leather were measured using a VMS PV-Series apparatus produced by G&P Technology.

[0096] An initial load of 900 gf/cm2 was applied to a spherical indenter and the load was maintained for 30 seconds. Subsequently, 30 seconds after the initial load was removed, a maximum thickness (T1) of the artificial leather was measured to a level of 1/1,000 mm. The initial load was applied for 30 seconds again and a minimum thickness (T2) was measured to a level of 1/1,000 mm. Subsequently, 30 seconds after the initial load was removed, the thickness (T3) of the artificial leather was measured to a level of 1/1,000 mm. In addition, a compressibility and a recovery rate were calculated using the following equation.



[TABLE 3]
No. of Ex.Elastic recoveryTextureSurface textureFriction propertyCompressibility (%)Recovery rate (%)
Ex. 1 90 0.10 13.5 95.0
Ex. 2 87 0.21 12.0 93.0
Ex. 3 92 0.10 15.3 95.3
Ex. 4 93 0.09 18.2 97.0
Ex. 5 93 0.15 15.5 96.5
Ex. 6 92 0.20 13.0 95.1
Ex. 7 89 0.15 13.0 94.7
Ex. 8 87 0.18 14.3 95.2
Ex. 9 88 0.22 16.1 95.0
Ex. 10 82 0.25 10.2 92.2
Comp. Ex. 1 76 0.35 7.3 70
Comp. Ex. 2 78 × Δ 0.33 8.0 78



Claims

1. A method for manufacturing an artificial leather comprising:

preparing two or more types of island-in-sea conjugate fibers, each comprising a sea component and an island component, wherein island components of the two or more types of island-in-sea conjugate fibers are two or more types of polyester polymers having different numbers of repeat units of -CH2-;

forming a non-woven fabric using the two or more types of island-in-sea conjugate fibers;

impregnating a polymeric elastomer in the non-woven fabric;

passing the polymeric elastomer-impregnated non-woven fabric through a hot roller to compress the polymeric elastomer-impregnated non-woven fabric; and

eluting the sea components from the two or more types of island-in-sea conjugate fibers to form an ultrafine non-woven fabric,

wherein a temperature of the hot roller is maintained within a range of 80 to 200°C, and, the artificial leather has a recovery rate of 80% or more,

wherein recovery rate is measured using a VMS PV-Series apparatus produced by G&P Technology as follows:

an initial load of 900 gf/cm2 is applied to a spherical indenter and the load is maintained for 30 seconds;

subsequently, 30 seconds after the initial load is removed, a maximum thickness (T1) of the artificial leather is measured to a level of 1/1,000 mm;

the initial load is applied for 30 seconds again and a minimum thickness (T2) is measured to a level of 1/1,000 mm;

subsequently, 30 seconds after the initial load is removed, the thickness (T3) of the artificial leather is measured to a level of 1/1,000 mm,

and, a recovery rate is calculated using the following equation,


 
2. An artificial leather comprising:

a non-woven fabric comprising short fibers having a fineness of 0.00111 to 0.555 dtex (0.001 to 0.5 denier); and

a polymeric elastomer impregnated in the non-woven fabric,

wherein the short fibers are two or more types of polyester short fibers having different numbers of repeat units of -CH2-, and

the artificial leather is manufactured by a method comprising:

preparing two or more types of island-in-sea conjugate fibers, each comprising a sea component and an island component, wherein island components of the two or more types of island-in-sea conjugate fibers are two or more types of polyester polymers having different numbers of repeat units of -CH2-;

forming a non-woven fabric using the two or more types of island-in-sea conjugate fibers;

impregnating a polymeric elastomer in the non-woven fabric;

passing the polymeric elastomer-impregnated non-woven fabric through a hot roller to compress the polymeric elastomer-impregnated non-woven fabric; and

eluting the sea components from the two or more types of island-in-sea conjugate fibers to form an ultrafine non-woven fabric,

wherein a temperature of the hot roller is maintained within a range of 80 to 200°C, and

wherein the artificial leather has a recovery rate of 80% or more, wherein recovery rate is measured using a VMS PV-Series apparatus produced by G&P Technology as follows:

an initial load of 900 gf/cm2 is applied to a spherical indenter and the load is maintained for 30 seconds;

subsequently, 30 seconds after the initial load is removed, a maximum thickness (T1) of the artificial leather is measured to a level of 1/1,000 mm;

the initial load is applied for 30 seconds again and a minimum thickness (T2) is measured to a level of 1/1,000 mm;

subsequently, 30 seconds after the initial load is removed, the thickness (T3) of the artificial leather is measured to a level of 1/1,000 mm,

and, a recovery rate is calculated using the following equation,


 
3. The artificial leather according to claim 2, wherein number of the repeat units of each of the two or more types of polyester short fibers is two to four.
 
4. The artificial leather according to claim 2, wherein the non-woven fabric comprises 5 to 95% by weight of polyethylene terephthalate short fibers.
 
5. The artificial leather according to claim 2, wherein the non-woven fabric has a weight variation coefficient of 20% or less,
wherein the weight variation coefficient (CV%) is calculated by collecting samples at various positions of the non-woven fabric, measuring a weight per unit area of the samples, calculating a standard deviation and an arithmetic mean using the measured weight per unit area and obtaining the weight variation coefficient in accordance with the following Equation:


 
6. The artificial leather according to claim 2, wherein the two or more types of polyester short fibers have a length of 5 to 100 mm.
 
7. The artificial leather according to claim 2, wherein an elastic recovery of the artificial leather at an elongation of 10% is 80% or more,
wherein the elastic recovery is measured as follows:

a sample in which a distance of 200 mm is marked is mounted on a tensile tester in which a distance between clamps are 250 mm, elongated to an elongation of 10% at a speed of 50 mm/min and is stood for one minute;

subsequently, the load is removed at the same speed as the tensile strength, the sample is stood for three minutes, an actual distance (x) of the distance marked above is measured and elastic recovery is measured in accordance with the following equation;


 
8. The artificial leather according to claim 2, wherein a difference between a friction coefficient in a forward direction parallel to a nap direction of the artificial leather and a friction coefficient in a reverse direction of the forward direction is 0.30 or less,
wherein the friction coefficient in the forward direction which is a direction such as nap direction and the friction coefficient in the reverse direction opposite to the nap direction are measured using a friction tester produced by Toyoseiko Co., Ltd.,
wherein identical test specimens are used as upper and lower friction materials and the upper material is set such that the nap direction thereof is opposite to a movement direction of the friction tester,
the lower friction material is adhered during measurement of friction coefficient in the forward direction such that the friction tester movement direction is equivalent to the nap direction, and,
the lower friction material is adhered during measurement of friction coefficient in the reverse direction such that the friction tester movement direction is opposite to the nap direction,
under conditions including a movement distance of about 20 cm and a balance weight of 200 g of the lower friction material, an object to which a friction force is applied, a load cell of 1 kg and a chart scale of X1, friction coefficients are measured three times and an average of the obtained measures is calculated to obtain a final friction coefficient value, and
the values of friction coefficients are determined by reading a maximum static frictional force.
 
9. The artificial leather according to claim 2, wherein the artificial leather has a compressibility of 8 to 50%,
wherein compressibility is measured using a VMS PV-Series apparatus produced by G&P Technology as follows:

an initial load of 900 gf/cm2 is applied to a spherical indenter and the load is maintained for 30 seconds,

subsequently, 30 seconds after the initial load is removed, a maximum thickness (T1) of the artificial leather is measured to a level of 1/1,000 mm,

the initial load is applied for 30 seconds again and a minimum thickness (T2) is measured to a level of 1/1,000 mm,

subsequently, 30 seconds after the initial load is removed, the thickness (T3) of the artificial leather is measured to a level of 1/1,000 mm,

and, a compressibility is calculated using the following equation,


 


Ansprüche

1. Verfahren zum Herstellen eines Kunstleders, das umfasst:

Erstellen von zwei oder mehr Arten von Insel-im-Meer-Konjugatfasern, die jeweils eine Meerkomponente und eine Inselkomponente umfassen, wobei Inselkomponenten der zwei oder mehr Arten von Insel-im-Meer-Konjugatfasern zwei oder mehr Arten von Polyesterpolymeren mit unterschiedlichen Anzahlen von Wiederholungseinheiten von - CH2- sind;

Ausbilden eines Vliesstoffs unter Verwendung der zwei oder mehr Arten von Insel-im-Meer-Konjugatfasern;

Imprägnieren eines polymeren Elastomers in dem Vliesstoff;

Führen des mit polymerem Elastomer imprägnierten Vliesstoffs durch eine heiße Walze, um den mit polymerem Elastomer imprägnierten Vliesstoff zu komprimieren; und

Eluieren der Meerkomponenten aus den zwei oder mehr Arten von Insel-im-Meer-Konjugatfasern, um einen ultrafeinen Vliesstoff auszubilden,

wobei eine Temperatur der heißen Walze innerhalb eines Bereichs von 80 bis 200 °C gehalten wird, und

das Kunstleder eine Rückstellungsrate von wenigstens 80 % aufweist,

wobei die Rückstellungsrate unter Verwendung einer Einrichtung der VMS PV-Serie, die von G&P Technology angefertigt wird, wie folgt gemessen wird:

eine Anfangslast von 900 gf/cm2 wird auf einen kugelförmigen Indenter angelegt und die Last wird 30 Sekunden lang gehalten;

anschließend wird 30 Sekunden nachdem die Anfangslast entfernt wurde eine Maximaldicke (T1) des Kunstleders auf eine Höhe von 1/1000 mm gemessen;

die Anfangslast wird erneut 30 Sekunden lang angelegt und eine Mindestdicke (T2) wird auf eine Höhe von 1/1.000 mm gemessen;

anschließend wird 30 Sekunden nachdem die Anfangslast entfernt wurde die Dicke (T3) des Kunstleders auf eine Höhe von 1/1000 mm gemessen und

eine Rückstellungsrate wird unter Verwendung der folgenden Gleichung berechnet:


 
2. Kunstleder, das umfasst:

einen Vliesstoff, der Kurzfasern mit einer Feinheit von 0,00111 bis 0,555 dtex (0,001 bis 0,5 Denier) umfasst; und

ein polymeres Elastomer, das in dem Vliesstoff imprägniert ist,

wobei die Kurzfasern zwei oder mehr Arten von Polyester-Kurzfasern mit unterschiedlichen Anzahlen von Wiederholungseinheiten von -CH2,- sind, und

das Kunstleder durch ein Verfahren hergestellt wird, das umfasst:

Erstellen von zwei oder mehr Arten von Insel-im-Meer-Konjugatfasern, die jeweils eine Meerkomponente und eine Inselkomponente umfassen, wobei Inselkomponenten der zwei oder mehr Arten von Insel-im-Meer-Konjugatfasern zwei oder mehr Arten von Polyesterpolymeren mit unterschiedlichen Anzahlen von Wiederholungseinheiten von - CH2- sind;

Ausbilden eines Vliesstoffs unter Verwendung der zwei oder mehr Arten von Insel-im-Meer-Konjugatfasern;

Imprägnieren eines polymeren Elastomers in dem Vliesstoff;

Führen des mit polymerem Elastomer imprägnierten Vliesstoffs durch eine heiße Walze, um den mit polymerem Elastomer imprägnierten Vliesstoff zu komprimieren; und

Eluieren der Meerkomponenten aus den zwei oder mehr Arten von Insel-im-Meer-Konjugatfasern, um einen ultrafeinen Vliesstoff auszubilden,

wobei eine Temperatur der heißen Walze innerhalb eines Bereichs von 80 bis 200 °C gehalten wird und

wobei das Kunstleder eine Rückstellungsrate von wenigstens 80 % aufweist, wobei die Rückstellungsrate unter Verwendung einer Einrichtung der VMS PV-Serie, die von G&P Technology angefertigt wird, wie folgt gemessen wird:

eine Anfangslast von 900 gf/cm2 wird auf einen kugelförmigen Indenter angelegt und die Last wird 30 Sekunden lang gehalten;

anschließend wird 30 Sekunden nachdem die Anfangslast entfernt wurde eine Maximaldicke (T1) des Kunstleders auf eine Höhe von 1/1000 mm gemessen;

die Anfangslast wird erneut 30 Sekunden lang angelegt und eine Mindestdicke (T2) wird auf eine Höhe von 1/1.000 mm gemessen;

anschließend wird 30 Sekunden nachdem die Anfangslast entfernt wurde die Dicke (T3) des Kunstleders auf eine Höhe von 1/1000 mm gemessen und

eine Rückstellungsrate wird unter Verwendung der folgenden Gleichung berechnet:


 
3. Kunstleder nach Anspruch 2, wobei die Anzahl der Wiederholungseinheiten von jeder der zwei oder mehr Arten von Polyester-Kurzfasern zwei bis vier beträgt.
 
4. Kunstleder nach Anspruch 2, wobei der Vliesstoff 5 bis 95 Gew.-% von Polyethylenterephthalat-Kurzfasern umfasst.
 
5. Kunstleder nach Anspruch 2, wobei der Vliesstoff einen Gewichtsvariationskoeffizienten von höchstens 20 % aufweist,
wobei der Gewichtsvariationskoeffizient (CV%) durch Sammeln von Proben an verschiedenen Positionen des Vliesstoffs, Messen eines Gewichts pro Flächeneinheit der Proben, Berechnen einer Standardabweichung und eines arithmetischen Mittels unter Verwendung des gemessenen Gewichts pro Flächeneinheit und Erhalten des Gewichtsvariationskoeffizienten gemäß der folgenden Gleichung berechnet wird:
Gewichtsvariationskoeffizient (CV%) = Standardabweichung/arithmetisches Mittel.
 
6. Kunstleder nach Anspruch 2, wobei die zwei oder mehr Arten von Polyester-Kurzfasern eine Länge von 5 bis 100 mm aufweisen.
 
7. Kunstleder nach Anspruch 2, wobei eine elastische Rückstellung des Kunstleders bei einer Dehnung von 10 % wenigstens 80 % ist, wobei die elastische Rückstellung wie folgt gemessen wird:

eine Probe, in der ein Abstand von 200 mm markiert ist, wird an einem Zugprüfgerät gelagert, in dem ein Abstand zwischen Klemmen 250 mm beträgt, wird bei einer Geschwindigkeit von 50 mm/min auf eine Dehnung von 10 % gedehnt und eine Minute lang stehengelassen;

anschließend wird die Last mit der gleichen Geschwindigkeit wie die Zugfestigkeit entfernt, die Probe drei Minuten lang stehen gelassen, ein tatsächlicher Abstand (x) des oben markierten Abstands gemessen und die elastische Rückstellung gemäß der folgenden Gleichung gemessen;


 
8. Kunstleder nach Anspruch 2, wobei eine Differenz zwischen einem Reibungskoeffizienten in einer Vorwärtsrichtung parallel zu einer Strichrichtung des Kunstleders und einem Reibungskoeffizienten in einer Rückwärtsrichtung der Vorwärtsrichtung höchstens 0,30 beträgt,
wobei der Reibungskoeffizient in der Vorwärtsrichtung, die eine Richtung wie etwa die Strichrichtung ist, und der Reibungskoeffizient in der Rückwärtsrichtung entgegengesetzt zu der Strichrichtung unter Verwendung eines Reibungsprüfgeräts, das von Toyoseiko Co., Ltd. angefertigt wird, gemessen werden,
identische Prüfkörper als obere und untere Reibungsmaterialien verwendet werden und das obere Material derart festgelegt wird, dass die Strichrichtung davon einer Bewegungsrichtung des Reibungsprüfgeräts entgegengesetzt ist,
das untere Reibungsmaterial während der Messung des Reibungskoeffizienten in der Vorwärtsrichtung derart angeklebt wird, dass die Reibungsprüfgerätbewegungsrichtung der Strichrichtung gleicht und
das untere Reibungsmaterial während der Messung des Reibungskoeffizienten in der Rückwärtsrichtung derart angeklebt wird, dass die Reibungsprüfgerätbewegungsrichtung der Strichrichtung entgegengesetzt ist,
unter Bedingungen, die einen Bewegungsabstand von etwa 20 cm und ein Gegengewicht von 200 g des unteren Reibungsmaterials, ein Objekt, an das eine Reibungskraft angelegt wird, eine Lastdose von 1 kg und einen Diagrammmaßstab von X1 einschließt, wobei Reibungskoeffizienten dreimal gemessen werden und ein Durchschnitt der erhaltenen Messungen berechnet wird, um einen endgültigen Reibungskoeffizientenwert zu erhalten, und
wobei die Werte der Reibungskoeffizienten durch Ablesen einer statischen Maximalreibungskraft bestimmt werden.
 
9. Kunstleder nach Anspruch 2, wobei das Kunstleder eine Komprimierbarkeit von 8 bis 50 % aufweist,
wobei die Komprimierbarkeit unter Verwendung einer Einrichtung der VMS PV-Serie, die von G&P Technology angefertigt wird, wie folgt gemessen wird:

eine Anfangslast von 900 gf/cm2 wird auf einen kugelförmigen Indenter angelegt und die Last wird 30 Sekunden lang gehalten,

anschließend wird 30 Sekunden nachdem die Anfangslast entfernt wurde eine Maximaldicke (T1) des Kunstleders auf eine Höhe von 1/1.000 mm gemessen,

die Anfangslast wird erneut 30 Sekunden lang angelegt und eine Mindestdicke (T2) auf eine Höhe von 1/1000 mm gemessen,

anschließend wird 30 Sekunden nachdem die Anfangslast entfernt wurde die Dicke (T3) des Kunstleders auf eine Höhe von 1/1.000 mm gemessen

und eine Komprimierbarkeit wird unter Verwendung der folgenden Gleichung berechnet:


 


Revendications

1. Procédé de fabrication d'un cuir artificiel comprenant :

la préparation de deux types ou plus de fibres conjuguées îlot-mer, comprenant chacune un composant mer et un composant îlot, les composants îlot des deux types ou plus de fibres conjuguées îlot-mer étant deux types ou plus de polymères polyester ayant différents nombres d'unités de répétition de -CH2- ;

la formation d'un textile non tissé à l'aide des deux types ou plus de fibres conjuguées îlot-mer ;

l'imprégnation d'un élastomère polymère dans le textile non tissé ;

le passage du textile non tissé imprégné d'élastomère polymère à travers un rouleau chaud pour comprimer le textile non tissé imprégné d'élastomère polymère ; et

l'élution des composants mer à partir des deux types ou plus de fibres conjuguées îlot-mer pour former un textile non tissé ultrafin, dans lequel la température du rouleau chaud est maintenue dans une plage de 80 à 200 °C, et, le cuir artificiel a un taux de récupération de 80 % ou plus, le taux de récupération étant mesuré à l'aide d'un appareil de la série PV VMS produit par G&P Technology comme suit :

une charge initiale de 900 gf / cm 2 est appliquée sur un pénétrateur sphérique et la charge est maintenue pendant 30 secondes ;

puis, 30 secondes après le retrait de la charge initiale, une épaisseur maximale (T1) du cuir artificiel est mesurée à un niveau de 1/1 000 mm ;

la charge initiale est à nouveau appliquée pendant 30 secondes et une épaisseur minimale (T2) est mesurée à un niveau de 1/1 000 mm ;

ensuite, 30 secondes après le retrait de la charge initiale, l'épaisseur (T3) du cuir artificiel est mesurée à un niveau de 1/1 000 mm et un taux de récupération est calculé à l'aide de l'équation suivante, Taux de récupération (%) = [(T3 - T2) / (T1 - T2)] × 100.


 
2. Cuir artificiel comprenant :

un textile non tissé comprenant des fibres courtes ayant une finesse de 0,00111 à 0,555 dtex (0,001 à 0,5 denier) ; et

un élastomère polymère imprégné dans le textile non tissé, dans lequel les fibres courtes sont deux types ou plus de fibres courtes en polyester ayant différents nombres d'unités de répétion de -CH2-, et

le cuir artificiel est fabriqué par un procédé comprenant :

la préparation de deux types ou plus de types de fibres conjuguées îlot-mer, comprenant chacune un composant mer et un composant îlot, les composants îlot des deux types ou plus de fibres conjuguées îlot-mer étant deux ou plusieurs types de polymères polyester ayant différents nombres d'unités de répétition de -CH2- ;

la formation d'un textile non tissé à l'aide des deux types ou plus de fibres conjuguées d'îlot-mer ;

l'imprégnation d'un élastomère polymère dans le textile non tissé ;

le passage du textile non tissé imprégné d'élastomère polymère à travers un rouleau chaud pour comprimer le textile non tissé imprégné d'élastomère polymère ; et

l'élution des composants de la mer à partir des deux types ou plus de fibres conjuguées îlot-mer pour former un textile non tissé ultrafin, dans lequel la température du rouleau chaud est maintenue dans une plage de 80 à 200 °C, et dans lequel le cuir artificiel a un taux de récupération de 80 % ou plus, le taux de récupération étant mesuré à l'aide d'un appareil de la série PV VMS produit par G&P Technology comme suit :

une charge initiale de 900 gf / cm 2 est appliquée sur un pénétrateur sphérique et la charge est maintenue pendant 30 secondes ;

puis, 30 secondes après le retrait de la charge initiale, une épaisseur maximale (T1) du cuir artificiel est mesurée à un niveau de 1/1 000 mm ;

la charge initiale est à nouveau appliquée pendant 30 secondes et une épaisseur minimale (T2) est mesurée à un niveau de 1/1 000 mm ;

ensuite, 30 secondes après le retrait de la charge initiale, l'épaisseur (T3) du cuir artificiel est mesurée à un niveau de 1/1 000 mm et un taux de récupération est calculé à l'aide de l'équation suivante, Taux de récupération (%) = [(T3 - T2) / (T1 - T2)] × 100


 
3. Cuir artificiel selon la revendication 2, dans lequel le nombre des unités de répétition de chacun des deux types ou plus de fibres courtes en polyester est de deux à quatre.
 
4. Cuir artificiel selon la revendication 2, dans lequel le textile non-tissé comprend 5 à 95 % en poids de fibres courtes de polyéthylène téréphtalate.
 
5. Cuir artificiel selon la revendication 2, dans lequel le textile non tissé a un coefficient de variation de poids de 20 % ou moins, dans lequel le coefficient de variation de poids (CV%) est calculé en collectant des échantillons à différentes positions du textile non-tissé, en mesurant un poids par unité de surface des échantillons, en calculant un écart-type et une moyenne arithmétique à l'aide du poids mesuré par unité de surface et en obtenant le coefficient de variation de poids conformément à l'équation suivante :
coefficient de variation de poids (CV%) = écart type / moyenne arithmétique.
 
6. Cuir artificiel selon la revendication 2, dans lequel les deux types ou plus de fibres courtes en polyester ont une longueur de 5 à 100 mm.
 
7. Cuir artificiel selon la revendication 2, dans lequel une récupération élastique du cuir artificiel à un allongement de 10 % est de 80 % ou plus, la récupération élastique étant mesurée comme suit :

un échantillon dans lequel une distance de 200 mm est marquée est monté sur un testeur de traction dans lequel une distance entre les pinces est de 250 mm, allongée à un allongement de 10 % à une vitesse de 50 mm / min et est maintenue pendant une minute ;

ensuite, la charge est enlevée à la même vitesse que la résistance à la traction, l'échantillon est maintenu pendant trois minutes, une distance réelle (x) de la distance indiquée ci-dessus est mesurée et la récupération élastique est mesurée conformément à l'équation suivante ;


 
8. Cuir artificiel selon la revendication 2, dans lequel une différence entre un coefficient de frottement dans une direction avant parallèle à une direction de la fibre du cuir artificiel et un coefficient de frottement dans une direction inverse de la direction avant est de 0,30 ou moins, dans lequel le coefficient de frottement dans la direction avant qui est une direction telle que la direction de la fibre et le coefficient de frottement dans la direction inverse opposée à la direction de la fibre sont mesurés à l'aide d'un testeur de friction produit par Toyoseiko Co., Ltd., dans lequel des échantillons identiques sont utilisés comme des matériaux de frottement supérieurs et inférieurs et le matériau supérieur est placé de telle sorte que sa direction de fibre est opposée à une direction de mouvement du testeur de frottement, le matériau de frottement inférieur est collé pendant la mesure du coefficient de frottement dans la direction avant de telle sorte que la direction de mouvement du testeur de friction soit équivalent à la direction de la fibre, et le matériau frottement inférieur est collé pendant la mesure du coefficient de frottement dans le sens inverse de telle sorte que le sens de déplacement du testeur de frottement soit opposé au sens de la fibre, dans des conditions comprenant une distance de déplacement d'environ 20 cm et un contrepoids de 200 g du matériau de frottement inférieur, un objet auquel une force de frottement est appliqué, une cellule de charge de 1 kg et une échelle de graphique de X1, les coefficients de frottement sont mesurés trois fois et une moyenne des mesures obtenues est calculée pour obtenir une valeur finale de coefficient de frottement, et les valeurs des coefficients de frottement sont déterminées en lisant une force de frottement statique maximale.
 
9. Cuir artificiel selon la revendication 2, dans lequel le cuir artificiel a une compressibilité de 8 à 50 %, la compressibilité étant mesurée à l'aide d'un appareil de la série PV VMS produit par G&P Technology comme suit :
une charge initiale de 900 gf / cm2 est appliquée sur un pénétrateur sphérique et la charge est maintenue pendant 30 secondes, puis 30 secondes après la suppression de la charge initiale, une épaisseur maximale (T1) du cuir artificiel est mesurée à un niveau de 1/1 000 mm, la charge initiale est à nouveau appliquée pendant 30 secondes et une épaisseur minimale (T2) est mesurée à un niveau de 1/1 000 mm, ensuite, 30 secondes après le retrait de la charge initiale, l'épaisseur (T3) du cuir artificiel est mesurée à un niveau de 1/1 000 mm et une compressibilité est calculée à l'aide de l'équation suivante, Compressibilité (%) = [(T1 - T2) / T1] × 100
 






Cited references

REFERENCES CITED IN THE DESCRIPTION



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Patent documents cited in the description