JP4489985B2 - Synthetic leather - Google Patents

Description

【００２６】
表１において、表面傷付き性は、ＪＩＳ Ｋ ７２０４に準拠して測定した。但し、摩耗輪はＣＳ−１０、荷重は１ｋｇｆ×２０００回にした。
耐寒性は、ＪＩＳ Ｋ ６７７２に準拠して合格する最も低い温度を示した。 高周波ウェルダー性は、市販の機械を用いて実際に溶着加工し、混合樹脂同士の接着性を剥離試験によって評価した。○は剥離時に材料破壊、×は剥離時に界面剥離を表す。
柔軟性は、製造した各レザーを手で触り、その感触を軟質ポリ塩化ビニルレザー（合成樹脂層がポリ塩化ビニル１００重量部に可塑剤フタル酸ジエチルヘキシル１００重量部配合したポリ塩化ビニル組成物であるレザー）と対比して評価した。○は軟質ポリ塩化ビニルレザーと同等の感触を有する、△は軟質ポリ塩化ビニルレザーよりやや硬い感触を有する、×は感触が硬く、軟質ポリ塩化ビニルレザーの代替不可、を表す。
縫い目の広がり状態は、各レザーを使用して椅子の上貼りを縫製で行ない、その縫い目の状態を目視で観察した。○は縫い目が広がらない、×は縫い目が拡がり商品性がない、を表す。
復元性は、直径０．５ｍｍの針を２ｍｍ突き刺し（貫通する）た後、針を引き抜き、その後の針の刺し跡の変化を目視して調べた。◎は刺し跡がすぐになくなる、○は刺し跡が一時間後になくなる、△は１時間後に刺し跡は分かるが孔は残っていない、×は一時間後に刺し跡に孔が残っている、を表す。
【００２７】
【発明の効果】
本発明の合成樹脂レザーは、柔軟性、復元性、耐寒性、耐表面傷付き性がよく、また高周波ウエルダーによって溶着加工できる利点があると共に、ミシンなどで縫製したとき、縫い目がが広がったり、縫い目から裂けたりすることがない。したがって、自動車の車両内装材、袋物素材、家具の表皮材として有用である。そして、従来の軟質ポリ塩化ビニルレザーに代替できる合成樹脂レザーとしても有用である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a synthetic resin leather using a mixed resin of a copolyester resin and an acrylic soft resin.
[0002]
[Prior art]
Synthetic resin leather used for automobile interior materials, bag materials, furniture skin materials, and the like is required to be flexible and strong. Conventionally, however, sheet bases such as woven fabrics, knitted fabrics or nonwoven fabrics, or polyolefin foams have been used. In general, a soft polyvinyl chloride layer is formed on the surface of a material. However, in recent years, polyolefin resin leather using random polypropylene, ethylene-vinyl acetate resin, hydrogenated styrene butadiene rubber or the like has been proposed in place of soft polyvinyl chloride due to recycling problems.
[0003]
However, compared to soft polyvinyl chloride leather, polyolefin resin leather has problems such as the surface being easily scratched and lack of high-frequency welder properties, and is also inferior in flame retardancy, so it is phosphoric acid-based or boric acid-based. If the flame retardant is not blended, there is a problem that it does not have the flame retardancy to withstand regulations. Therefore, the present applicant previously provided an acrylic soft resin layer on at least one side of the base material as a synthetic resin leather that has flexibility and resilience, excellent surface scratch resistance, and can be welded with a high-frequency welder. Acrylic resin leather was proposed (Japanese Patent Application No. 2000-349405). This acrylic resin leather is excellent as a synthetic resin leather that can replace conventional soft polyvinyl chloride leather, but it has the problem that when sewing with a sewing machine, it has the problem that the seam spreads and tears easily from the seam. It was.
[0004]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and has solved the disadvantage that the seam spreads or tears easily from the seam when it is sewn with a sewing machine or the like without impairing the excellent properties of the above acrylic resin leather. The object is to provide resin leather.
[0005]
[Means for Solving the Problems]
That is, the present invention is a synthetic resin leather in which a mixed resin layer of 40 to 95% by weight of a copolyester resin and 60 to 5% by weight of an acrylic soft resin is provided on at least one side of a substrate. This mixed resin layer preferably further contains 5 to 40 parts by weight of an elastomer with respect to 100 parts by weight of the mixed resin. Moreover, it is preferable to mix | blend a plasticizer with a synthetic resin layer. As the plasticizer, an aromatic carboxylic acid ester is preferable. Moreover, a woven fabric, a knitted fabric, or a nonwoven fabric is used as a base material of this invention. The substrate may be a soft foam sheet, or a laminate of a woven fabric, a knitted fabric or a nonwoven fabric and a soft foam sheet.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The synthetic resin leather of the present invention is a synthetic resin leather in which a mixed resin layer of a copolymer polyester resin 40 to 95% by weight and an acrylic soft resin 60 to 5% by weight is provided on at least one surface of a base material. As this base material, a woven fabric, a knitted fabric or a non-woven fabric is used. The materials of these knitted fabrics are polyamide fiber, polyester fiber, acrylic fiber, polypropylene fiber, cotton, rayon, and blended yarns thereof. Examples of the knitted fabric include a double-sided knitted fabric and a tentacle knitted fabric. Examples of the woven fabric include a plain woven fabric, a twill woven fabric, and a satin woven fabric. Moreover, a soft foam sheet can also be used for a base material. Examples of the flexible foam sheet include polypropylene foam, electron beam cross-linked polypropylene foam, polyethylene foam, electron beam cross-linked polyethylene foam, and polyurethane foam. Moreover, the laminated body of a woven fabric, a knitted fabric, or a nonwoven fabric and a soft foam sheet can also be used for a base material. In this case, it is preferable to adopt the configuration of a woven fabric, a knitted fabric or a nonwoven fabric-soft foam sheet-mixed resin layer.
[0007]
The copolymerized polyester resin used in the present invention is obtained by random copolymerization using one or both of a polyvalent carboxylic acid and a polyhydric alcohol with two or more kinds of polyvalent carboxylic acids or polyhydric alcohols. Such a copolyester resin has a low crystallinity, a low melting point, is softer at room temperature than a highly crystalline polyester, and has a preferable flexibility when made into leather. Further, those having lower crystallinity and having a Tm of 200 ° C. or less are preferable, and in particular, a so-called amorphous polyester having no melting point (Tm) when measured with a differential scanning calorimeter (DSC) is flexible and workable. And is preferably used. This copolymerized polyester resin is suitable for processing by mixing with an acrylic soft resin because it becomes soft and processable at a calendering temperature of about 140 to 200 ° C., which is the calendering temperature of an acrylic soft resin described later.
[0008]
Examples of the aliphatic carboxylic acid used in the production of the copolymer polyester resin include adipic acid, glutaric acid, succinic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, and the like. Examples of the system include 1,4-cyclohexanedicarboxylic acid, cyclohexanediacetic acid and the like, and aromatics include terephthalic acid, orthophthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,6-naphthalenedimethylenecarboxylic acid, And divalent carboxylic acids such as paraphenylene dicarboxylic acid; trivalent carboxylic acids such as trimellitic acid; and tetravalent carboxylic acids such as pyromellitic acid. The maximum amount of trivalent or higher carboxylic acid is preferably about 0.5% mol. In addition, acid anhydrides, esters and acid chlorides corresponding to these acids can also be used.
[0009]
The polyhydric alcohol used for the production of the copolyester resin is ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1, Examples include 6-hexanediol, diethylene glycol, triethylene glycol, polyethylene glycol (up to a degree of polymerization of about 5), polytetramethylene glycol, 2,2-dimethyltrimethylene glycol, hexamethylene glycol, neopentyl glycol, and the like. Tri- and tetrahydric alcohols such as trimethylolpropane and pentaerythritol can also be used. Examples of the alicyclic system include 1,4-cyclohexanedimethanol, and examples of the aromatic include bisphenol A. The trivalent or higher alcohol is preferably used in a maximum amount of about 0.5% mol from the viewpoint of moldability of the copolyester resin.
[0010]
Among the above polyvalent carboxylic acids and polyhydric alcohols, for example, copolymer polyester resins copolymerized using, for example, 1,4-cyclohexanedicarboxylic acid or 1,4-cyclohexanedimethanol that has a ring structure and is difficult to rotate. The glass transition point tends to be high, and the tendency to harden the synthetic resin leather is strong. In addition, copolymer polyester resins copolymerized using adipic acid or 1,6-hexanediol having a flexible methylene chain tend to soften synthetic resin leather because of its low glass transition point and flexibility. . Therefore, it is better to adjust the blending ratio of the copolymerized polyester resin and the acrylic soft resin, and further the blending amount of the elastomer and the blending amount of the plasticizer to make a desired synthetic resin leather with a desired texture and touch. .
[0011]
As the copolyester resin used in the present invention, a copolyester resin having a glass transition point of 50 ° C. or lower, particularly a glass transition point of 20 ° C. or lower is preferable because it has flexibility and the softness necessary for synthetic resin leather. Examples of the copolyester having a glass transition point of 50 ° C. or less include Mitsubishi Rayon DC427 (glass transition point of 3 to 5 ° C.). Further, a copolyester resin having a glass transition point exceeding 50 ° C. can be used in combination. Examples of the copolyester resin include a copolyester having about 70% ethylene glycol unit and about 30% 1,4-cyclohexanedimethanol unit ( Eastman Chemical Co., Ltd. PETG6763: glass transition point 81 ° C.).
[0012]
The acrylic soft resin used in the present invention is a resin exhibiting flexibility such as soft polyvinyl chloride at room temperature. The acrylic soft resin is preferably a multilayer structure polymer, that is, a polymer in which two or more kinds of acrylic polymers form a core-shell type multilayer structure. These acrylic soft resins exhibit good flexibility at room temperature, have bending durability, and excellent weather resistance.
[0013]
An example of the acrylic soft resin used in the present invention is shown. 30 to 99.9% by weight of at least one alkyl acrylate ester having 1 to 12 carbon atoms, 0 to 70% by weight of at least one methacrylic acid alkyl ester having 1 to 8 carbon atoms, copolymerization Tg formed by polymerizing a monomer mixture consisting of 0 to 30% by weight of a possible unsaturated monomer, 0.1 to 10% by weight of a polyfunctional crosslinkable monomer and / or a polyfunctional graft monomer. 10 to 90 parts by weight of at least one polymer layer [A] having a temperature of 30 ° C. or less, 30 to 99% by weight of an alkyl acrylate ester having an alkyl group having 1 to 12 carbon atoms, and 1 to 8 carbon atoms The Tg formed by polymerizing a monomer mixture comprising 1 to 70% by weight of at least one alkyl methacrylate having an alkyl group and 0 to 30% by weight of a copolymerizable unsaturated monomer is -20. An acrylic soft multilayer resin having a multilayer structure polymer composed of a combination of 90 to 10 parts by weight of at least one polymer layer [B] at 50 ° C., and the outermost layer being a polymer layer [B]. is there.
[0014]
Another example of the acrylic soft resin is shown. 60 to 99.5% by weight of acrylic acid alkyl ester having 1 to 8 carbon atoms, 0 to 39.5% by weight of monofunctional monomer having one copolymerizable vinyl group, and vinyl group or vinylidene 30 to 80 parts by weight of a rubber layer obtained by polymerizing 0.5 to 5% by weight of a polyfunctional monomer having at least two groups, 40 to 100% by weight of methyl methacrylate, and 1 to 8 carbon atoms From 20 to 70 parts by weight of a hard resin layer obtained by polymerizing 0 to 60% by weight of an alkyl acrylate ester having an alkyl group and 0 to 20% by weight of a monomer having a copolymerizable vinyl group or vinylidene group It is an acrylic soft multilayer structure resin that is configured and whose outermost layer is a hard resin layer. When a lubricant is added to this resin, calendar molding becomes smooth.
[0015]
Furthermore, other examples of acrylic soft resins are shown. (A) 80-98.99% by weight of methyl methacrylate, 1-20% by weight of an acrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms, 0.01-1% by weight of a multifunctional grafting agent, and multifunctional crosslinking 5-30 parts by weight of an innermost hard polymer layer obtained by polymerizing a monomer mixture comprising 0 to 0.5% by weight of an agent; (B) an alkyl acrylate 70 having an alkyl group having 1 to 8 carbon atoms Intermediate obtained by polymerizing a monomer mixture consisting of ˜99.5 wt%, methyl methacrylate 0-30 wt%, polyfunctional grafting agent 0.5-5 wt% and polyfunctional cross-linking agent 0-5 wt% 20 to 45 parts by weight of a hard polymer layer; (C) a monomer mixture consisting of 90 to 99% by weight of methyl methacrylate and 10 to 1% by weight of an alkyl acrylate ester having an alkyl group having 1 to 8 carbon atoms. Do it Consists outermost hard polymer layer 50 to 75 parts by weight, average particle size is an acrylic soft multilayer resin 0.01 to 0.3 [mu] m.
[0016]
In the synthetic resin leather of the present invention, a mixed resin of the above copolymerized polyester resin and an acrylic soft resin is used for forming the synthetic resin layer. The blending ratio of the copolyester resin and the acrylic soft resin is 40 to 95% by weight of the copolyester resin, 60 to 5% by weight of the acrylic soft resin, preferably 50 to 90% by weight of the copolyester resin, and the soft acrylic resin. The resin is 50 to 10% by weight, more preferably 70 to 90% by weight of the copolyester resin, and 30 to 10% by weight of the acrylic soft resin. If the copolymerized polyester resin is less than 40% by weight, the seam is easy to spread or tear, while if the copolymerized polyester resin exceeds 95% by weight, it feels hard and is not suitable for use as leather.
[0017]
In the synthetic resin leather of the present invention, the mixed resin layer may contain an elastomer. By containing an elastomer, it has a soft texture with a feeling of elasticity, and has a high restorability. As the elastomer, rubber and thermoplastic elastomer are used. Examples of the rubber include natural rubber, SBR, polybutadiene, butyl rubber, chloroprene rubber, white cone rubber, fluorine rubber, acrylic rubber, urethane rubber, and nitrile rubber. Examples of the thermoplastic elastomer include styrene, polyolefin, polyurethane, polyvinyl chloride, polyester, and polyamide. Of these rubbers and thermoplastic elastomers, partially crosslinked rubbers and dynamically crosslinked thermoplastic elastomers are preferred because of their good shape retention at high temperatures. In particular, nitrile partially crosslinked rubber is preferable because of its good compatibility with the above mixed resin. The blending ratio in the mixed resin layer is 5 to 40 parts by weight, preferably 5 to 20 parts by weight with respect to 100 parts by weight of the mixed resin of the copolyester resin and the acrylic soft resin.
[0018]
Moreover, when a plasticizer is blended in the mixed resin layer, the flexibility and feel of the product can be improved. Plasticizers include phthalate esters such as di-2-ethylhexyl phthalate, isobutyl phthalate, diisodecyl phthalate; trimellitic esters such as tri-2-ethylhexyl trimellitic acid; di-2 ethylhexyl adipate, di-isononyl adipate Aliphatic dibasic acid esters such as di-2-ethylhexyl sebacate; epoxy plasticizers such as epoxidized soybean oil and epoxy butyl stearate; phosphate esters such as tricresyl phosphate; citric acids such as tributyl acetylcitrate Esters are used. Of these, aromatic carboxylic acid esters such as phthalic acid esters and trimellitic acid esters are preferably used from the viewpoint of high plasticization efficiency and few problems such as bleeding.
[0019]
If necessary, the mixed resin layer may further contain a lubricant, an ultraviolet absorber, a light stabilizer, a pigment, an antibacterial agent, and the like that are generally used for blending synthetic resins. As the lubricant, aliphatic metal salts of stearic acid such as calcium, magnesium, zinc and barium, polyethylene wax, stearic acid, alkylenebisfatty acid amide and the like are used. As the ultraviolet absorber, a benzotriazole-based ultraviolet absorber such as 2- (2′-hydroxy-5′-methylphenyl) benzotriazole is used. As the light stabilizer, hindered amine light stabilizers such as bis- (2,2,6,6-tetramethyl-4-piperidyl) sebacate are used. As the antibacterial agent, a silver-based inorganic antibacterial agent or the like is used.
[0020]
The synthetic resin leather of the present invention is produced as follows. That is, for example, a copolymerized polyester resin and an acrylic soft resin are mixed at a predetermined ratio, and if necessary, an elastomer, and if necessary, additives such as a plasticizer and a lubricant are blended, and then kneaded well. A mixed resin sheet is formed by molding into a sheet having a thickness of 0.1 to 5 mm by calendar molding or extrusion molding. An adhesive is applied to the knitted fabric of the base material, and the mixed resin sheet is stacked on the adhesive-coated surface and heated and pressurized to some extent so as not to shift. Then, if necessary, marble printing is performed, a matting treatment agent is applied, and then pressure is applied with a squeezing roll heated to 150 to 200 ° C. By this pressure heating, the base material and the mixed resin sheet are integrated, and leather is obtained. Moreover, you may provide a mixed resin layer on both surfaces of the knitted fabric of a base material. Further, a soft foam sheet such as a polypropylene foam sheet may be bonded to the knitted fabric in advance with an adhesive, and a mixed resin layer may be formed on the surface of the soft foam sheet in the same manner as described above to obtain leather.
[0021]
For adhesion between the base material and the mixed resin sheet, ethylene-vinyl acetate copolymer emulsion, polyvinyl chloride paste, two-component polyurethane adhesive, or the like is used. This adhesive may be applied to the base fabric surface or may be applied to the mixed resin sheet surface. In order to bond the base material and the polypropylene foam sheet, and the polypropylene foam sheet and the mixed resin sheet, a primer layer for improving adhesiveness such as a polyurethane primer layer or an epoxy resin primer layer is provided on the laminated surface of the polypropylene foam sheet. It may be provided.
[0022]
In addition, when the mixed resin sheet is calendered and wound into a roll and the sheet is unwound from this roll, depending on the type and blending of the mixed resin, blocking may occur and separation of the sheets may be difficult. By blending a small amount of a fatty acid amide and / or a metal soap, especially a fatty acid amide, the above blocking can be eliminated without using a slip paper.
[0023]
The synthetic resin leather of the present invention is used for vehicle interiors (seats, headrests, tonneau covers, sun visors, ceilings, etc.) for automobiles, indoor interior materials, skin materials for motorcycle saddles, skin materials for furniture (chairs, sofas, etc.), Used for bag materials such as bags, kappa, and aprons. In addition, a material in which a mixed resin layer is provided on both surfaces of a base knitted fabric is used as a material for a flexible container. Further, leather based on a soft foam sheet is also used for vehicle interiors (instrument panels, doors, ceilings, etc.).
[0024]
【Example】
Next, the present invention will be described in more detail with reference to Examples and Comparative Examples.
Examples 1-3, Comparative Examples 1-2
As Examples 1 to 3, copolymer polyester resin (Mitsubishi Rayon Co., Ltd .: DC-427), acrylic soft resin (Kuraray Co., Ltd .: SA-10000P), partially crosslinked nitrile rubber (Nippon Zeon Co., Ltd .: Nipol DN214), plasticizer (trioctyl trimellitic acid), calendar lubricant (manufactured by Daikyo Kasei Co., Ltd .: AX518I), ultraviolet absorber (benzotriazole), antioxidant (phenol, phosphite) and pigment The ratios shown in Table 1 (numbers indicate parts by weight) were blended, and a sheet having a thickness of 0.35 mm was formed by calendering.
An ethylene-vinyl acetate emulsion adhesive was applied to a polyester fiber woven fabric. The sheet was laminated on this adhesive application surface and heated and pressed to some extent, and adhered to the extent not to be displaced. Thereafter, pressure was applied with a squeezing roll heated to 180 ° C. The synthetic knitted fabric and the mixed resin sheet were integrated to obtain the synthetic resin leather of the present invention.
Further, as Comparative Examples 1 and 2, the case of using a copolymerized polyester resin alone and the case of using an acrylic soft resin alone are shown. Blended in the proportions shown in Table 1, leather was produced in the same manner as in Examples 1 to 3.
The leather manufactured in this example and comparative example was examined for surface scratch resistance, cold resistance, high-frequency welder property, flexibility, seam spreading state, and restorability. The results are also shown in Table 1.
[0025]
[Table 1]

[0026]
In Table 1, the surface damage property was measured according to JIS K7204. However, the wear wheel was CS-10, and the load was 1 kgf × 2000 times.
The cold resistance showed the lowest temperature that passed in accordance with JIS K 6772. The high-frequency welder was actually welded using a commercially available machine, and the adhesion between the mixed resins was evaluated by a peel test. ○ represents material destruction during peeling, and × represents interfacial peeling during peeling.
Flexibility is achieved by touching each manufactured leather with a soft polyvinyl chloride leather (a polyvinyl chloride composition in which a synthetic resin layer is blended with 100 parts by weight of polyvinyl chloride and 100 parts by weight of plasticizer diethylhexyl phthalate). It was evaluated against a certain leather. ○ indicates a feel equivalent to that of soft polyvinyl chloride leather, Δ indicates a slightly harder feel than soft polyvinyl chloride leather, and × indicates a hard feel that cannot be replaced with soft polyvinyl chloride leather.
The spread of the seam was performed by sewing the leather on top of the chair and observing the seam visually. ○ indicates that the seam does not spread, and × indicates that the seam is wide and there is no merchantability.
Restorability was examined by visually observing a change in the puncture mark of the needle after the needle was pulled out (penetrated) by 2 mm and then pulled out (penetrated). ◎ indicates that the stab mark disappears immediately, ◯ indicates that the stab mark disappears after one hour, △ indicates that the stab mark remains after one hour but no holes remain, and × indicates that a hole remains in the stab mark after one hour. To express.
[0027]
【The invention's effect】
The synthetic resin leather of the present invention has good flexibility, resilience, cold resistance, surface scratch resistance, and has an advantage that it can be welded by a high-frequency welder, and when stitched with a sewing machine, the seam spreads, There is no tear from the seam. Therefore, it is useful as a vehicle interior material, a bag material, and a skin material for furniture. It is also useful as a synthetic resin leather that can replace conventional soft polyvinyl chloride leather.

Claims (6)

A synthetic resin leather in which a mixed resin layer of 40 to 95% by weight of a copolyester resin and 60 to 5% by weight of an acrylic soft resin is provided on at least one side of a substrate. The synthetic resin leather according to claim 1, wherein the mixed resin layer further contains 5 to 40 parts by weight of an elastomer with respect to 100 parts by weight of the mixed resin. The synthetic resin leather according to claim 1 or 2, wherein the mixed resin layer contains a plasticizer. The synthetic resin leather according to claim 3, wherein the plasticizer is an aromatic carboxylic acid ester. The synthetic resin leather according to any one of claims 1 to 4, wherein the substrate is a woven fabric, a knitted fabric, or a nonwoven fabric. The synthetic resin leather according to any one of claims 1 to 4, wherein the base material is a soft foam sheet.