JP2000345477A - Foamed polyolefin leather - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a foamed polyolefin leather having excellent flexural resistance and softness and produce a foamed polyolefin leather having excellent resistance to swelling with soil attached by handling. SOLUTION: This foamed polyolefin leather is composed of a fiber substrate layer, a foamed layer composed of a mixture of 30-95 wt.% ethylene-α-olefin copolymer elastomer and 70-5 wt.% styrene-based copolymer and a non-foamed layer composed of a polyolefin elastomer laminated one upon another in the order. A coating layer composed of a fluorine-based treating agent may be applied to the surface of the non-foamed layer composed of the polyolefin elastomer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leather in which a foamed synthetic resin layer and a non-foamed synthetic resin layer are sequentially provided on the surface of a fiber base material layer.

[0002]

2. Description of the Related Art Conventionally, leather used as a skin material for car seats, saddles for bicycles and motorcycles, chairs, sofas, etc. has a soft polyvinyl chloride layer laminated on the surface of a fiber base material such as woven fabric, knitted fabric, and nonwoven fabric. Polyvinyl chloride leather has been used. However, in recent years, polyolefin-based leather in which a polyolefin-based elastomer layer is laminated on a fiber base material has come to be used, and in particular, a polyolefin-based foamed leather having a good feeling and a high-grade feel has been demanded in the market. Then, demands for improvement in bending resistance and flexibility of this polyolefin foamed leather are made by users. Further, sheet-like articles made of a polyolefin-based resin have a drawback that they are swollen and deformed (wavy) by human hand scales (oily components from the human body). Conventionally, it has been proposed to provide an ultraviolet-curable coating layer on the surface in order to solve this drawback. However, if this method is applied to a polyolefin-based leather, there is a problem that the flexibility of the leather is impaired.

[0003]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances, and is directed to a foamed polyolefin-based leather excellent in bending resistance and flexibility, and a foamed polyolefin-based leather excellent in hand swelling resistance. The purpose is to provide leather.

[0004]

The present invention provides a fiber base material layer,
Ethylene-α-olefin copolymer elastomer 30-9
A foamed polyolefin leather characterized in that a foamed layer made of a mixture of 5% by weight and 70 to 5% by weight of a styrene copolymer elastomer and a non-foamed layer made of a polyolefin elastomer are sequentially laminated. .
Further, it is a foamed polyolefin-based leather in which a coating layer of a fluorine-based treating agent is provided on the surface of a non-foamed layer made of the above-mentioned polyolefin-based elastomer.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The fibrous base material layer in the present invention is a woven fabric (eg, plain weave), a knitted fabric (eg, single-sided knit, double-sided knitted) or a nonwoven fabric. The material fiber is cotton,
Natural fibers such as hemp; regenerated fibers such as rayon; semi-synthetic fibers such as acetate; polyamide fibers such as nylon 6 fibers, polyester fibers such as polyethylene terephthalate fibers, acrylic fibers such as polyacrylonitrile fibers, and polyolefins such as polypropylene fibers. Synthetic fibers such as system fibers and vinylon; inorganic fibers such as glass fibers and carbon fibers are used. The fibrous base material may be made of the above-mentioned long fibers or short fibers, or may be one or a combination of two or more fibers. In particular, knitted fabrics have good elasticity, so car seats,
Suitable for leather used for saddles, chairs, sofas, etc.

A foamed layer comprising a mixture of 30 to 95% by weight of an ethylene-α-olefin copolymer elastomer and 70 to 5% by weight of a styrene copolymer elastomer in the present invention will be described. The ethylene-α-olefin copolymer elastomer is preferably a random copolymer of ethylene and another α-olefin. Other α-olefins include, for example, propylene, 1-butene, 4-methyl-1-
Penten, 1-hexene, 1-octene, 1-decene and the like can be mentioned. Of these, propylene and 1-butene are preferably used. In particular, an ethylene-1-butene copolymer is particularly preferable because it appropriately softens at a foaming temperature of about 200 degrees.

This ethylene-α-olefin copolymer elastomer has an effect of improving the flexibility of the foamed layer. From the viewpoint of the softening effect, a random copolymer having an ethylene content of 35 to 95 mol% is preferable, and a random copolymer having an ethylene content of 40 to 92 mol% is particularly preferable. Furthermore, from the viewpoint of the softening effect, the crystallinity measured by the X-ray diffraction method is 0 to
A copolymer of 30% is preferred, and a copolymer of 0 to 20% is particularly preferred.

The styrene copolymer elastomers include styrene-butadiene-styrene block copolymer, styrene-butadiene block copolymer, styrene-isoprene-styrene block copolymer, and styrene-isoprene block copolymer. Styrene-SBR-styrene block copolymer, styrene-SBR block copolymer, etc., and particularly those obtained by hydrogenating them. The hydrogenated copolymer does not necessarily have to have all double bonds saturated. Examples of commercially available products include ToughTech manufactured by Asahi Kasei Kogyo Co., Ltd., Hibler manufactured by Kuraray Co., Ltd., and Clayton G manufactured by Shell Chemical Co., Ltd. The copolymer is preferably a random copolymer, particularly preferably a hydrogenated product of a styrene-butadiene random copolymer. As this commercially available product, for example, JS
Dynaron manufactured by R company is exemplified. By blending this styrene-based copolymer, the foaming process can be facilitated by expanding the softening temperature range which is more flexible at normal temperature and suitable for foaming.

The ethylene-α-olefin copolymer elastomer and the styrene-based copolymer elastomer have a content of 30 to 9
5: 70-5 weight ratio, preferably 60-80: 40
Mix at a weight ratio of ~ 20. The foamed layer is prepared by blending the above mixture with a chemical foaming agent to prepare a foamable composition, forming the foamable composition on a fiber base material by calendering or coating, and then heating the chemical foaming agent. It is formed by foaming. Examples of the chemical foaming material include azodicarbonamide (ADCA), p, p'-oxybisbenzenesulfonyl hydrazide (OBSH), paratoluenesulfonyl hydrazide (TSH), and dinitropentamethylenetetramine (DPT). Two or more of these can be used as a mixture. The expansion ratio of the foamed layer is not particularly limited, but is preferably about 1.5 to 4 times as good as the product.

When the layer of the foamable composition is formed on the fiber base material by calendering or coating, the foamable composition may be directly formed on the fiber base material. It is preferable to provide it. As the adhesive, an adhesive having excellent flexibility and flexibility is preferable.For example, a polyester-based adhesive obtained by reacting a polyol such as polyester polyol and polyether polyol with a diisocyanate such as tolylene diisocyanate and diphenylenemethane diisocyanate is preferable. preferable. Further, a layer of an ethylene-methyl methacrylate copolymer or an ethylene-methyl methacrylate-maleic anhydride copolymer may be formed on a fiber base material, and the above-mentioned foamed layer may be formed thereon.

The polyolefin elastomer of the non-foamed layer in the present invention forms a leather surface, is soft and tough, and is obtained by mechanically mixing an olefin rubber (such as an ethylene-propylene copolymer rubber) and a polyolefin resin. A partially crosslinked blended elastomer obtained by adding an organic peroxide to a mixture of an olefin rubber and a polyolefin resin, kneading and partially crosslinking the mixture, and partially crosslinked using an organic peroxide. A partially crosslinked blended elastomer obtained by mixing an olefin rubber and a polyolefin resin, and a completely crosslinked blended elastomer of an olefin rubber and a polyolefin resin are used. In particular, a partially cross-linked blend type elastomer, for example, an elastomer obtained by dynamically cross-linking a polypropylene resin and an ethylene-propylene rubber, has good heat resistance,
Since it does not cause any trouble during foaming, it is preferably used. Examples of commercially available products include Mirastomer manufactured by Mitsui Chemicals, Inc.

The above-mentioned foamed layer and non-foamed layer may each contain, if necessary, an antistatic agent, an antioxidant such as a phenol or phosphorus compound, and a light stabilizer such as a hindered amine compound.
Various additives such as a lubricant, an ultraviolet absorber, a pigment, and an inorganic filler may be added. Known additives used for olefin resins are preferably used as such additives.

Further, the fluorine-based treating agent layer in the present invention is a layer provided on the surface of a non-foamed layer made of a polyolefin-based elastomer in order to prevent swelling of hand marks. By forming a normal fluorine-based resin layer, hand swelling can be prevented, but the flexibility (deformability) of the present invention is impaired. The fluorine-based treating agent used in the present invention is a two-component curable solution obtained by dissolving a solvent-soluble fluororesin for a room-temperature-curable coating material in an appropriate solvent. When this treating agent is used, the problems described above are solved. Is done. Examples of the fluorine-based treating agent include a vinylidene fluoride-based polymer, a fluoroolefin / hydrocarbon-based olefin copolymer, a fluoroacrylate copolymer, and a fluoroepoxy compound. Among them, a fluoroacrylate-based copolymer is particularly preferred because it can impart swelling resistance to hand marks without impairing the flexibility and bending resistance of the leather.

The fluorine-based treatment agent layer is provided by applying a solvent solution of the fluorine-based treatment agent. Since the fluorine-based treating agent has low adhesion to the non-foamed layer of the polyolefin-based elastomer, it is preferable to perform primer treatment using a binder. As the binder, a known adhesive having an adhesive property to the fluororesin and the polyolefin, for example, a urethane-based binder is used. Also, a gloss adjusting agent,
For example, by blending a silica powder or the like with a fluorine-based treating agent, the swelling resistance treatment and the gloss adjustment treatment can be combined. Further, marble printing may be performed between the primer treatment and the fluorine treatment. Also, a squeezing process may be performed after the foaming process. This squeezing treatment may be performed before or after providing the fluorine-based treatment agent layer. Also,
The treatment with the fluorine-based treatment agent may be performed after the squeezing treatment, and the fluorine-based treatment agent layer may be provided only on the top portion of the squeezing.

Embodiment 1 FIG. 0.35 thickness as fiber base material
mm double-sided knitting made of rayon was used. A urethane-based adhesive was applied to one surface. On top of that, Tuffmer TX-6
12 (Ethylene-1-butene copolymer manufactured by Mitsui Chemicals, Inc.)
70 parts by weight, Dynaron 1320P (hydrogenated styrene-butadiene random copolymer, manufactured by JSR Corporation) 30
Parts by weight, a foaming mixture consisting of 3 parts by weight of a chemical foaming agent (azodicarbonamide) and a small amount of a lubricant are sheeted with a calender to a thickness of 0.2 mm, and further a milastomer 5030NH (partially cross-linked polyolefin manufactured by Mitsui Chemicals, Inc.) A mixture obtained by blending a small amount of an antioxidant, an ultraviolet absorber, a light stabilizer, and a lubricant with each other to form a 0.2 mm-thick calender sheet. Then
This laminate was passed through a furnace at 225 ° C. to foam the chemical blowing agent. Further, the leather was obtained by performing a squeezing treatment, a primer treatment, a marble print, and a gloss treatment. In the measurement after the squeezing process, the thickness of the foam layer was 0.45 mm,
The expansion ratio was 2.25 times. The leather thus obtained was excellent in flexibility and bending resistance.

Embodiment 2 FIG. 0.35 thickness as fiber base material
mm double-sided knitting made of rayon was used. A urethane-based adhesive was applied to one surface. On top of that, Tuffmer TX-6
12 (Ethylene-1-butene copolymer manufactured by Mitsui Chemicals, Inc.)
70 parts by weight, Dynaron 1320P (hydrogenated styrene-butadiene random copolymer, manufactured by JSR Corporation) 30
Parts by weight, a foaming mixture consisting of 3 parts by weight of a chemical foaming agent (azodicarbonamide) and a small amount of a lubricant are sheeted by calendering to a thickness of 0.2 mm, and further a milastomer 5030NH (partially cross-linked polyolefin based on Mitsui Chemicals, Inc.) A mixture of an elastomer, an antioxidant, an ultraviolet absorber, a light stabilizer, and a lubricant in a small amount was sheeted by a calender to a thickness of 0.2 mm. Next, LU-43 was placed on the sheeting surface of Mirastomer 5030NH.
04 / LU3017C (urethane-based binder manufactured by Dainichi Seika Kogyo Co., Ltd.) was applied twice as a primer. Further, a fluorine-based surface treatment agent FA5753 / FA5759 /
Coronate HL) (manufactured by Seiko Kasei Corporation: FA5753,
FA5759 was coated twice with a fluoroacrylate-based copolymer, and Coronate HL was coated with an isocyanate-based curing agent twice. The laminate thus prepared was passed through a furnace at 225 ° C. to foam a chemical blowing agent. Further narrowing processing was performed. The thickness of the foamed layer after the squeezing process was 0.45 mm, and the foaming ratio was 2.25 times. The leather thus obtained was excellent in flexibility and bending resistance. In addition, artificial grease (oil and grease similar to grease) is applied to this,
When heated to ℃, no swelling was observed even after 6 hours. On the other hand, the leather from which the treatment with the fluorine-based surface treating agent was omitted swelled significantly in one hour.

[0017]

The leather of the present invention is excellent in bending resistance and flexibility despite using a polyolefin resin. Further, by providing a coating layer of a fluorine-based treating agent on the surface of the leather, so-called swelling of hand stains can be prevented. Therefore, the foamed polyolefin-based leather of the present invention is extremely useful as a skin material for automobile seats, saddles for bicycles and motorcycles, chairs, sofas and the like.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tomokazu Inaba 1 Kobe, Yoshida-cho, Haibara-gun, Shizuoka Okamoto Co., Ltd. Shizuoka Plant (72) Inventor Yoshimasa Fujita 1 Kobe, Yoshida-cho, Harihara-gun, Shizuoka Okamoto Shizuoka F-term in factory (reference) 4F055 AA21 BA13 BA15 CA16 DA08 EA22 FA05 FA12 FA17 FA38 GA20 HA17 4F100 AH06C AJ04 AK03C AK12B AK17C AK51G AK62B AK63B AK73B AL01B AL05B AL09B AL09C BA03 BA07 BA10B01 BA10 GB81 JK13 JK17

Claims (2)

[Claims] 1. A fiber base layer, a foamed layer comprising a mixture of 30 to 95% by weight of an ethylene-α-olefin copolymer elastomer and 70 to 5% by weight of a styrene-based copolymer elastomer, and a non-woven fabric comprising a polyolefin-based elastomer. A foamed polyolefin-based leather, wherein foamed layers are sequentially laminated. 2. A foamed polyolefin-based leather according to claim 1, wherein a coating layer of a fluorine-based treating agent is provided on the surface of the non-foamed layer made of a polyolefin-based elastomer.