Laminate

Abstract

Provided is a laminate provided with a rubber layer (A) and a fluororesin layer (B) laminated on the rubber layer (A), in which the rubber layer (A) is a conductive layer and is formed from a rubber composition containing a rubber and carbon black, the content of the carbon black in the rubber composition being 1.0-100 parts by mass per 100 parts by mass of the rubber, and the fluororesin layer (B) is formed from a fluororesin layer (B) laminated on the rubber layer (A). The carbon black has a nitrogen adsorption specific surface area of 140 m2 / g or less, and the fluororesin layer (B) is formed from a melt-moldable fluororesin.

Description

Technical Field

[0001] The present invention relates to a laminate. Background Art

[0002] Patent Document 1 describes a laminate comprising a fluororubber layer (A) and a fluoropolymer layer (B) on the fluororubber layer (A), wherein:

[0003] The fluororubber layer (A) is a layer made of a cross-linked fluororubber composition, the cross-linked fluororubber composition containing uncross-linked fluororubber, silica particles and a basic multifunctional compound, the average value of the product of "(particle size)×(roundness)" of the silica particles is 17.5 nm or more and 500 μm or less, and the silica particles are contained in the cross-linked fluororubber composition in an amount of 1 part by mass or more and 70 parts by mass or less relative to 100 parts by mass of the uncross-linked fluororubber,

[0004] The fluoropolymer layer (B) is a layer made of a fluoropolymer composition, wherein the fluoropolymer composition comprises a fluoropolymer, wherein the fluoropolymer is a chlorotrifluoroethylene copolymer or a tetrafluoroethylene copolymer, wherein the tetrafluoroethylene copolymer comprises a tetrafluoroethylene unit and a fluoropolymer selected from the group consisting of perfluoro(alkyl vinyl ether), vinylidene fluoride and a general formula CX 8 X 9 =CX 10 Y(where X 8 , X 9 and X 10 are independently F or H, Y is -Cl or -Rf 5 -Br, Rf 5 A unit of at least one monomer selected from the group consisting of monomers represented by a single bond or a C1-C5 perfluoroalkylene group.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2020 / 170025 Summary of the invention

[0008] Problems to be solved by the invention

[0009] An object of the present invention is to provide a laminate comprising a rubber layer and a fluororesin layer, wherein the rubber layer has conductivity and the rubber layer and the fluororesin layer are firmly bonded to each other.

[0010] Means for solving problems

[0011] According to the present invention, there is provided a laminate comprising a rubber layer (A) and a fluororesin layer (B) laminated on the rubber layer (A), wherein the rubber layer (A) is a conductive layer formed from a rubber composition containing rubber and carbon black, the content of the carbon black in the rubber composition is 1.0 to 100 parts by mass relative to 100 parts by mass of the rubber, and the carbon black has a nitrogen adsorption specific surface area of ​​140 m 2 / g or less, and the fluororesin layer (B) is formed of a melt-moldable fluororesin.

[0012] Effects of the Invention

[0013] According to the present invention, there can be provided a laminate comprising a rubber layer and a fluororesin layer, wherein the rubber layer has conductivity and the rubber layer and the fluororesin layer are firmly bonded to each other. DETAILED DESCRIPTION

[0014] Hereinafter, specific embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments.

[0015] The laminate of the present invention comprises a rubber layer (A) and a fluororesin layer (B). Patent Document 1 describes a laminate comprising a fluororubber layer (A) and a fluoropolymer layer (B). However, a technology is required that can impart conductivity to the rubber layer of the laminate and can firmly bond the conductive rubber layer to the fluororesin layer.

[0016] In-depth research was conducted on means for solving the above-mentioned problems. As a result, it was found that by selecting carbon black having a nitrogen adsorption specific surface area in an extremely limited range from carbon black and mixing it into rubber in an appropriate amount, conductivity can be imparted to the rubber layer, and a laminate in which the conductive rubber layer and the fluororesin layer are firmly bonded can be obtained.

[0017] Next, each component constituting such a conventional laminate will be described in detail.

[0018] (A) Rubber layer

[0019] The rubber layer of the laminate of the present invention has electrical conductivity. The presence or absence of electrical conductivity of the rubber layer can be confirmed, for example, by measuring the surface resistance value of the rubber layer. From the viewpoint of sufficiently preventing the laminate from being charged, the surface resistance value of the rubber layer is preferably 10 MΩ or less, more preferably 5 MΩ or less, and further preferably 1 MΩ or less.

[0020] The surface resistance value of the rubber layer can be measured using, for example, an insulation resistance meter.

[0021] The rubber layer is a layer formed of a rubber composition. The rubber layer is usually obtained by molding the rubber composition to obtain an uncrosslinked rubber layer and then performing a crosslinking treatment.

[0022] The rubber composition contains rubber and carbon black.

[0023] (Carbon Black)

[0024] The rubber composition contains a nitrogen adsorption specific surface area of ​​140 m 2 By using carbon black with a large nitrogen adsorption specific surface area, a laminate in which the conductive rubber layer and the fluororesin layer are firmly bonded can be obtained.

[0025] The nitrogen adsorption specific surface area of ​​carbon black is 140m 2 / g or less, preferably 120m 2 / g or less, more preferably 100m 2 / g or less, more preferably 80m 2 / g or less, particularly preferably 75m 2 / g or less, and most preferably 70m 2 / g or less, more preferably 25m 2 / g or above.

[0026] The nitrogen adsorption specific surface area of ​​carbon black can be determined according to JIS K 6217-2.

[0027] The average primary particle size of carbon black is preferably 28 nm or more, more preferably 32 nm or more, further preferably 35 nm or more, and preferably 200 nm or less, further preferably 100 nm or less. By using carbon black having an average primary particle size within the above numerical range, a laminate in which the rubber layer and the fluororesin layer are more firmly bonded can be obtained.

[0028] The average primary particle size of carbon black is the arithmetic average particle size of primary particles of carbon black. The average primary particle size of carbon black can be determined by observing primary particles of carbon black using an electron microscope.

[0029] The content of the carbon black in the rubber composition is 1.0 to 100 parts by mass, preferably 3.0 parts by mass or more, more preferably 6.0 parts by mass or more, further preferably more than 8.0 parts by mass, particularly preferably 9.0 parts by mass or more, preferably 50 parts by mass or less, more preferably 30 parts by mass or less, further preferably 20 parts by mass or less, relative to 100 parts by mass of rubber. By setting the content of the carbon black having a large nitrogen adsorption specific surface area within the above range, the conductivity of the rubber layer and the adhesion between the rubber layer and the fluororesin layer can be improved, and the flexibility of the rubber layer and the physical properties of the rubber layer can be appropriately adjusted.

[0030] As the carbon black contained in the rubber composition, carbon black having conductivity is used. By selecting carbon black having conductivity, and further selecting carbon black having a nitrogen adsorption specific surface area in an extremely limited range, and mixing it into the rubber in an appropriate amount, conductivity can be imparted to the rubber layer, and a laminate in which the conductive rubber layer and the fluororesin layer are firmly bonded can be obtained. It is not easy to quantitatively evaluate the conductivity of carbon black itself, but in the laminate of the present invention, when carbon black is mixed in the rubber composition in a manner to achieve a content within the above range, carbon black having conductivity to the extent that conductivity can be imparted to the rubber layer is selected. In one embodiment, the type of carbon black and the content of carbon black are selected so that the surface resistance value of the rubber layer is within the above range.

[0031] (rubber)

[0032] Examples of the rubber contained in the rubber composition include diene rubbers such as acrylonitrile-butadiene rubber (NBR) or its hydrogenated product (HNBR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), butadiene rubber (BR), natural rubber (NR), isoprene rubber (IR), ethylene-propylene-termonomer copolymer rubber, silicone rubber, butyl rubber, epichlorohydrin rubber, acrylic rubber, chlorinated polyethylene (CPE), a polymerized mixture of acrylonitrile-butadiene rubber and vinyl chloride (PVC-NBR), ethylene propylene diene rubber (EPDM), chlorosulfonated polyethylene (CSM), and fluororubber.

[0033] As rubber, fluororubber is preferred. Fluororubber is usually composed of amorphous polymers having fluorine atoms bonded to carbon atoms constituting the main chain and having rubber elasticity. The above-mentioned fluororubber can be composed of one polymer or more than two polymers. Fluororubber usually does not have a clear melting point.

[0034] The fluororubber is preferably selected from vinylidene fluoride (VdF) / hexafluoropropylene (HFP) copolymer, VdF / HFP / tetrafluoroethylene (TFE) copolymer, TFE / propylene copolymer, TFE / propylene / VdF copolymer, ethylene / HFP copolymer, ethylene / HFP / VdF copolymer, ethylene / HFP / TFE copolymer, VdF / TFE / perfluoro(alkyl vinyl ether) (PAVE) copolymer, VdF / chlorotrifluoroethylene (CTFE) copolymer and VdF / CHX 1 =CX 2 R 1 (Where X 1 and X 2 One of them is H and the other is F, Rf 1It is at least one of the group consisting of linear or branched fluoroalkyl copolymers having 1 to 12 carbon atoms. The fluororubber is preferably a non-perfluororubber, and more preferably a copolymer containing a polymerized unit derived from vinylidene fluoride (VdF unit).

[0035] As a copolymer containing VdF units, preferably a copolymer containing VdF units and copolymerization units derived from fluorine-containing ethylenic monomers (wherein VdF units are excluded. Hereinafter, also referred to as "fluorine-containing ethylenic monomer units (a)"). The copolymer containing VdF units may be a copolymer consisting only of VdF units and fluorine-containing ethylenic monomer units (a), or may be a copolymer further containing copolymerization units derived from monomers copolymerizable with VdF and fluorine-containing ethylenic monomers (wherein VdF is excluded. Hereinafter, also referred to as "fluorine-containing ethylenic monomers (a)").

[0036] The copolymer containing VdF units preferably contains 30 mol % to 90 mol % of VdF units and 70 mol % to 10 mol % of fluorinated ethylenic monomer units (a), more preferably contains 30 mol % to 85 mol % of VdF units and 70 mol % to 15 mol % of fluorinated ethylenic monomer units (a), and further preferably contains 30 mol % to 80 mol % of VdF units and 70 mol % to 20 mol % of fluorinated ethylenic monomer units (a), relative to 100 mol % of the total of the VdF units and the fluorinated ethylenic monomer units (a).

[0037] The copolymerization units derived from the monomer copolymerizable with VdF and the fluorinated ethylenic monomer units (a) (excluding the VdF units) are preferably in an amount of 0 to 10 mol % based on the total amount of the VdF units and the copolymerization units derived from the fluorinated ethylenic monomer (a).

[0038] Examples of the fluorinated ethylenic monomer (a) include TFE, CTFE, trifluoroethylene, HFP, trifluoropropylene, tetrafluoropropylene, pentafluoropropylene, trifluorobutylene, tetrafluoroisobutylene, PAVE, vinyl fluoride, and the general formula (1):

[0039] CHX 1 =CX 2 R 1 (1)

[0040] (Where X 1 and X 2 One of them is H and the other is F, Rf 1 is a compound represented by a linear or branched fluoroalkyl group having 1 to 12 carbon atoms, general formula (2):

[0041] CFX=CXOCF2OR 1 (2)

[0042] (wherein, X is the same or different and represents H, F or CF3, R 1 The fluorinated monomer is a fluorinated monomer such as a fluorovinyl ether represented by formula (1). Among these, at least one selected from the group consisting of CH2=CFCF3, fluorovinyl ether represented by formula (2), TFE, HFP and PAVE is preferred, and at least one selected from the group consisting of TFE, HFP and PAVE is more preferred.

[0043] As PAVE, the general formula (3) is preferred:

[0044] CF2=CFO(CF2CFY 1 O) p -(CF2CF2CF2O) q -Rf (3)

[0045] (In the formula, Y 1 represents F or CF3, Rf represents a perfluoroalkyl group having 1 to 5 carbon atoms, p represents an integer of 0 to 5, and q represents an integer of 0 to 5. ) is a compound represented by.

[0046] As PAVE, perfluoro(methyl vinyl ether) or perfluoro(propyl vinyl ether) is more preferred, and perfluoro(methyl vinyl ether) is further preferred. These may be used alone or in any combination.

[0047] Examples of the monomer copolymerizable with VdF and the fluorine-containing ethylenic monomer (a) include ethylene, propylene, and alkyl vinyl ether.

[0048] As such a copolymer containing VdF units, specifically, at least one copolymer selected from the group consisting of VdF / HFP copolymers, VdF / HFP / TFE copolymers, VdF / CTFE copolymers, VdF / CTFE / TFE copolymers, VdF / PAVE copolymers, VdF / TFE / PAVE copolymers, VdF / HFP / PAVE copolymers, VdF / HFP / TFE / PAVE copolymers, VdF / CH2=CFCF3 copolymers and VdF / TFE / CH2=CFCF3 copolymers is preferred. Among these copolymers containing VdF units, at least one copolymer selected from the group consisting of VdF / HFP copolymers and VdF / HFP / TFE copolymers is particularly preferred from the perspective of heat resistance. These copolymers containing VdF units preferably satisfy the composition ratio of the above-mentioned VdF units to the fluorinated ethylenic monomer units (a).

[0049] As the VdF / HFP copolymer, the molar ratio of VdF / HFP is preferably 45 to 85 / 55 to 15, more preferably 50 to 80 / 50 to 20, and further preferably 60 to 80 / 40 to 20.

[0050] As the VdF / HFP / TFE copolymer, the molar ratio of VdF / HFP / TFE is preferably 30 to 85 / 5 to 50 / 5 to 40, the molar ratio of VdF / HFP / TFE is more preferably 35 to 80 / 8 to 45 / 8 to 35, the molar ratio of VdF / HFP / TFE is further preferably 40 to 80 / 10 to 40 / 10 to 30, and the molar ratio of VdF / HFP / TFE is most preferably 40 to 80 / 10 to 35 / 10 to 30.

[0051] As the VdF / PAVE copolymer, the molar ratio of VdF / PAVE is preferably 65-90 / 10-35.

[0052] As the VdF / TFE / PAVE copolymer, the molar ratio of VdF / TFE / PAVE is preferably 40 to 80 / 3 to 40 / 15 to 35.

[0053] As the VdF / HFP / PAVE copolymer, the molar ratio of VdF / HFP / PAVE is preferably 65 to 90 / 3 to 25 / 3 to 25.

[0054] As the VdF / HFP / TFE / PAVE copolymer, the molar ratio of VdF / HFP / TFE / PAVE is preferably 40 to 90 / 0 to 25 / 0 to 40 / 3 to 35, and more preferably 40 to 80 / 3 to 25 / 3 to 40 / 3 to 25.

[0055] The fluororubber is also preferably composed of a copolymer containing copolymer units from monomers providing crosslinking sites. As monomers providing crosslinking sites, iodine-containing monomers such as perfluoro(6,6-dihydro-6-iodo-3-oxo-1-hexene) or perfluoro(5-iodo-3-oxo-1-pentene) described in Japanese Patent Publication No. 5-63482 and Japanese Patent Publication No. 7-316234 can be cited; bromine-containing monomers described in Japanese Patent Publication No. 4-505341; cyano-containing monomers, carboxyl-containing monomers, alkoxycarbonyl-containing monomers, etc. described in Japanese Patent Publication No. 4-505345 and Japanese Patent Publication No. 5-500070 can be cited.

[0056] The fluororubber is also preferably a fluororubber having an iodine atom or a bromine atom at the end of the main chain. The fluororubber having an iodine atom or a bromine atom at the end of the main chain can be produced as follows: in a substantially oxygen-free state, in the presence of a halogen compound, a free radical initiator is added to an aqueous medium to carry out emulsion polymerization of the monomer, thereby producing the fluororubber. As a representative example of the halogen compound used, for example, the general formula:

[0057] R 2 I x Br y

[0058] (where x and y are integers from 0 to 2 and satisfy 1≤x+y≤2, R 2 A compound represented by a saturated or unsaturated fluorinated hydrocarbon group having 1 to 16 carbon atoms, a saturated or unsaturated chlorofluorocarbon group having 1 to 16 carbon atoms, a hydrocarbon group having 1 to 3 carbon atoms, or a cyclic hydrocarbon group having 3 to 10 carbon atoms which may be substituted with an iodine atom or a bromine atom, and which may contain an oxygen atom).

[0059] Examples of the halogen compound include 1,3-diiodoperfluoropropane, 1,3-diiodoperfluoropropane, 1,4-diiodoperfluorobutane, 1,5-diiodoperfluoropentane, 1,6-diiodoperfluorohexane, 1,8-diiodoperfluorooctane, 1,12-diiodoperfluorododecane, 1,16-diiodoperfluorohexadecane, diiodomethane, 1,2-diiodethane, 1,3-diiodoperfluoropropane, CF2Br2, BrCF2CF2Br, CF3CFBrCF2Br, CFClBr2, BrCF2CFC lBr, CFBrClCFClBr, BrCF2CF2CF2Br, BrCF2CFBrOCF3, 1-bromo-2-iodoperfluoroethane, 1-bromo-3-iodoperfluoropropane, 1-bromo-4-iodoperfluorobutane, 2-bromo-3-iodoperfluorobutane, 3-bromo-4-iodoperfluoro-1-butene, 2-bromo-4-iodoperfluoro-1-butene, mono-iodine and mono-bromine substitutions of benzene, di-iodine and mono-bromine substitutions of benzene, and (2-iodoethyl) and (2-bromoethyl) substitutions of benzene, etc. These compounds can be used alone or in combination with each other.

[0060] Among these, 1,4-diiodoperfluorobutane or diiodomethane is preferably used in view of polymerization reactivity, crosslinking reactivity, availability, and the like.

[0061] The Mooney viscosity (ML) of the fluororubber is preferably 0.0447 W / m. 1+10 The temperature (100° C.) is preferably 5 to 200, more preferably 10 to 150, further preferably 20 to 100.

[0062] The Mooney viscosity can be measured according to ASTM-D1646.

[0063] Measuring equipment: MV2000E manufactured by ALPHATECHNOLOGIES

[0064] Rotor speed: 2rpm

[0065] Measuring temperature: 100℃

[0066] The rubber composition preferably has a rubber component consisting solely of the above-mentioned fluororubber.

[0067] (Basic polyfunctional compound)

[0068] The rubber composition preferably further contains a basic polyfunctional compound. The rubber composition contains a basic polyfunctional compound, so that the rubber layer and the fluororesin layer can be more firmly bonded. The basic polyfunctional compound is a compound having two or more functional groups of the same or different structures in one molecule and exhibiting basicity.

[0069] The functional group possessed by the basic polyfunctional compound is preferably a functional group showing basicity, and is preferably selected from, for example, -NH2, -NH3 + 、-NHCOOH、-NHCOO - 、-N=CR 1 R 2 (Where R 1 and R 2 are independently an organic group having 0 to 12 carbon atoms), -NR 3 R 4 (Where R 3 and R 4 are independently an organic group having 0 to 12 carbon atoms), -NR 3 R 4 R 5 (Where R 3 , R 4 and R 5 is independently an organic group having 0 to 12 carbon atoms) and at least one of the group consisting of functional groups that change into the above functional groups by heating, more preferably selected from -NH2, -NH3 + 、-N=CR 1 R 2 (Where R 1 and R 2 Same as above) and -NR 3 R 4 R 5 (Where R 3 , R 4 and R 5Same as above), more preferably at least one selected from the group consisting of -NH2, -NH3 + and-N=CR 1 R 2 (Where R 1 and R 2 The number of functional groups possessed by the polyfunctional compound is not particularly limited to 2 or more, but is preferably 2 to 8, more preferably 2 to 4, further preferably 2 or 3, and particularly preferably 2.

[0070] The above R 1 , R 2 , R 3 , R 4 and R 5 Each of the above-mentioned hydrocarbon groups is preferably -H or an organic group having 1 to 12 carbon atoms, and is preferably -H or a hydrocarbon group having 1 to 12 carbon atoms. The hydrocarbon group may have one or more carbon-carbon double bonds. The hydrocarbon group preferably has 1 to 8 carbon atoms.

[0071] Preferably, the above R 1 is -H or -CH3, R 2 -CH=CHR 6 (R 6 is phenyl (-C6H5), benzyl (-CH2-C6H5) or -H), and more preferably the above R 1 -H, R 2 It is -CH=CH-C6H5.

[0072] Examples of the basic polyfunctional compound include ethylenediamine, propylenediamine, putrescine, cadaverine, 1,6-hexanediamine, heptanediamine, octanediamine, nonanediamine, decanediamine, undecanediamine, dodecanediamine, phenylenediamine, N,N'-dicinnamylidene-1,6-hexanediamine, N,N,N',N'-tetramethyl-1,6-hexanediamine, N,N'-dimethyl-1,6-hexanediamine, and 6-aminohexyluric acid.

[0073] The above-mentioned basic polyfunctional compound preferably contains at least 2 nitrogen atoms in the molecule, and the interatomic distance between nitrogen and nitrogen is The interatomic distance between nitrogen and nitrogen is more preferably The above, more preferably Above, particularly preferably By increasing the interatomic distance between nitrogen and nitrogen, the flexibility of the basic polyfunctional compound increases, and cross-linking becomes easier.

[0074] Here, the nitrogen-nitrogen interatomic distance was calculated as follows: That is, the structure optimization of each base was calculated using the density functional method (the program was Gaussian 03, the density functional was B3LYP, and the ground state function was 6-31G*).

[0075] As the basic polyfunctional compound, from the viewpoint of the adhesion between the rubber layer and the fluororesin layer, it is preferred to select N,N'-dicinnamylidene-1,6-hexanediamine and NH2-(CH2) n- At least one selected from the group consisting of NH2 (wherein n is 5 to 12), more preferably at least one selected from the group consisting of 1,6-hexanediamine and N,N'-dicinnamylidene-1,6-hexanediamine.

[0076] In the rubber composition, from the perspective of more firmly adhering the rubber layer and the fluororesin layer, the content of the basic polyfunctional compound is preferably 0.1 to 10 parts by mass, more preferably 1.0 parts by mass or more, further preferably 2.0 parts by mass or more, more preferably 7.0 parts by mass or less, further preferably 5.0 parts by mass or less, relative to 100 parts by mass of the rubber.

[0077] (Polytetrafluoroethylene)

[0078] The rubber composition preferably further contains polytetrafluoroethylene (PTFE) from the viewpoint of enabling the rubber layer and the fluororesin layer to be more firmly bonded to each other.

[0079] From the viewpoint of making the rubber layer and the fluororesin layer more firmly bonded, the specific surface area of ​​PTFE is preferably less than 8 m 2 / g, more preferably 6.0m 2 / g or less, more preferably 4.0m 2 / g or less, particularly preferably 3.0m 2 / g or less, preferably 0.5m 2 / g or more, more preferably 1.0 m 2 / g or above.

[0080] The specific surface area of ​​PTFE was measured by the BET method using a surface analyzer (trade name: BELSORP-miniII, manufactured by Microtrac BEL) using a mixed gas of 30% nitrogen and 70% helium as a carrier gas and cooling with liquid nitrogen.

[0081] PTFE preferably has melt processability. In addition, the melt viscosity of PTFE at 380°C is preferably 1×10 1 Pa·s~7×10 5 Pa·s.

[0082] The PTFE with melt viscosity in the above-mentioned scope is a PTFE with low molecular weight, for example, a number-average molecular weight of less than 600,000. " High molecular weight PTFE " with a number-average molecular weight exceeding 600,000 shows the unique fibrillation characteristics of PTFE (for example, with reference to Japanese Patent Laid-Open Gazette No. 10-147617). The melt viscosity of high molecular weight PTFE is high and is non-melt processability. The PTFE included in the rubber layer preferably does not show the fibrillation characteristics of the degree that can be carried out paste extrusion molding. The melt viscosity and number-average molecular weight of PTFE can be adjusted by adjusting the polymerization conditions of TFE when manufacturing PTFE or irradiating PTFE with electron beams.

[0083] Melt viscosity is the following value: according to ASTM D 1238, using a flow tester (manufactured by Shimadzu Corporation) and The above-mentioned melt viscosity is obtained by measuring a 2 g sample heated at 380°C for 5 minutes in a 8 L mold and holding it at the above temperature under a load of 0.7 MPa. The above-mentioned number average molecular weight is a value calculated from the melt viscosity measured by the above-mentioned measuring method.

[0084] The apparent density of PTFE is preferably 0.15 g / cm 3 ~0.80g / cm 3 , more preferably 0.25 g / cm 3 More preferably, 0.55 g / cm 3 the following.

[0085] The apparent density can be measured according to JIS K6891.

[0086] The average particle size of PTFE is preferably 0.01 μm to 1000 μm, more preferably 0.1 μm or more, further preferably 0.3 μm or more, particularly preferably 0.5 μm or more, more preferably 100 μm or less, further preferably 50 μm or less, particularly preferably 20 μm or less.

[0087] The average particle size is measured using a laser diffraction particle size distribution measuring apparatus (e.g., manufactured by Japan Laser Co., Ltd.) without using a cascade, at a pressure of 0.1 MPa and a measuring time of 3 seconds, and the value corresponding to 50% of the cumulative particle size distribution obtained is taken as the average particle size.

[0088] The melting point of PTFE is preferably 324°C to 333°C.

[0089] Regarding the melting point of PTFE, a differential scanning calorimeter RDC220 (DSC) manufactured by SII Nanotechnology was used. Temperature calibration was performed in advance using indium and lead as standard samples. Then, about 3 mg of PTFE powder was placed in an aluminum pan (capped container), and the temperature was increased at a rate of 10°C / min in a temperature range of 250°C to 380°C under an air flow of 200 ml / min. Differential scanning calorimetry was performed, and the minimum point of the heat of fusion in the above-mentioned range was taken as the melting point.

[0090] The melt flow rate (MFR) of PTFE at 372° C. (load: 1.2 kg) is preferably 0.01 g / 10 min to 10 g / 10 min.

[0091] The MFR can be determined by measuring the weight (g) of a polymer flowing out from a nozzle having a diameter of 2 mm and a length of 8 mm per unit time (10 minutes) at 372°C and a load of 1.2 kg using a melt flow indexer (for example, manufactured by Toyo Seiki Seisaku-sho, Ltd.).

[0092] The ignition loss (loss on ignition) of PTFE at 300° C. is preferably 0.05 mass % or more, more preferably 0.09 mass % or more, further preferably 0.15 mass % or more, and particularly preferably 0.30 mass % or more.

[0093] The ignition loss can be determined by heating PTFE (sample) at 300° C. for 2 hours, measuring the mass of the heated sample, and calculating the ratio of the mass loss of the heated sample to the mass of the sample before heating.

[0094] PTFE may be a homopolymer of TFE, or may be a modified PTFE including a TFE unit and a modified monomer unit copolymerizable with TFE.

[0095] In the modified PTFE, the content of the modified monomer unit copolymerizable with TFE is preferably 0.01 to 1% by mass, more preferably 0.01 to 0.5% by mass, and most preferably 0.03 to 0.3% by mass, based on all monomer units.

[0096] In the present invention, the modified monomer unit refers to a part of the molecular structure of the modified PTFE, which is the part from the modified monomer, and the total monomer unit refers to the part from all monomers in the molecular structure of the modified PTFE. The content of the modified monomer unit is the value measured by infrared spectroscopy or NMR (nuclear magnetic resonance).

[0097] The modifying monomer in the modified PTFE is not particularly limited as long as it can be copolymerized with TFE, and examples thereof include perfluoroolefins such as hexafluoropropylene [HFP]; fluorochloroolefins such as trifluorochloroethylene [CTFE]; hydrogen-containing fluoroolefins such as trifluoroethylene and vinylidene fluoride [VDF]; perfluorovinyl ether; perfluoroalkylethylene: ethylene, etc. In addition, the modifying monomer used may be one or more.

[0098] The perfluorovinyl ether is not particularly limited, and examples thereof include those of the general formula (I):

[0099] CF2=CF-ORf(I)

[0100] (wherein Rf represents a perfluoro organic group) and the like. In this specification, the above-mentioned "perfluoro organic group" refers to an organic group in which all hydrogen atoms bonded to carbon atoms are replaced by fluorine atoms. The above-mentioned perfluoro organic group may have an ether oxygen.

[0101] Examples of the perfluorovinyl ether include perfluoro(alkyl vinyl ether) [PAVE], wherein Rf in the general formula (I) represents a perfluoroalkyl group having 1 to 10 carbon atoms. The perfluoroalkyl group preferably has 1 to 5 carbon atoms.

[0102] Examples of the perfluoroalkyl group in the PAVE include perfluoromethyl, perfluoroethyl, perfluoropropyl, perfluorobutyl, perfluoropentyl, and perfluorohexyl. Preferably, the perfluoroalkyl group is perfluoropropyl vinyl ether [PPVE] in which the perfluoroalkyl group is perfluoropropyl.

[0103] Examples of the perfluorovinyl ether include:

[0104] In the general formula (I), Rf is a perfluoro(alkoxyalkyl) group having 4 to 9 carbon atoms, and Rf is the following formula:

[0105] [Chemistry 1]

[0106]

[0107] (wherein m represents 0 or an integer of 1 to 4), and Rf is the following formula:

[0108] CF3CF2CF2-(O-CF(CF3)-CF2) n -

[0109] (wherein n represents an integer of 1 to 4) and the like.

[0110] The perfluoroalkylethylene is not particularly limited, and examples thereof include perfluorobutylethylene (PFBE), perfluorohexylethylene, and perfluorooctylethylene.

[0111] As the modifying monomer in the modified PTFE, at least one monomer selected from the group consisting of HFP, CTFE, VDF, PPVE, PFBE and ethylene is preferred, and HFP is more preferred.

[0112] The PTFE is preferably a modified PTFE, and more preferably a modified PTFE containing a TFE unit and a polymerized unit derived from HFP (HFP unit).

[0113] From the viewpoint of appropriately adjusting the conductivity of the rubber layer and making the rubber layer and the fluororesin layer more firmly bonded, the content of PTFE in the rubber composition is preferably 0.5 to 100 parts by mass, more preferably 10 parts by mass or more, further preferably 20 parts by mass or more, more preferably 80 parts by mass or less, further preferably 60 parts by mass or less, and particularly preferably 45 parts by mass or less, based on 100 parts by mass of the rubber.

[0114] (Silicon Dioxide)

[0115] The rubber composition preferably further contains silica from the viewpoint of enabling the rubber layer and the fluororesin layer to be more firmly bonded to each other.

[0116] As silica, alkaline silica and acidic silica can be used. From the aspect of adhesion, alkaline silica is preferably used. As alkaline silica, Carplex 1120 (made by DSL Japan), Sidistar R300 (made by Elkem), Silene732D (made by PPG Industries), Inhibisil75 (made by PPG Industries), etc. can be cited. In addition, from the aspect of making the rubber layer and the fluororesin layer more firmly bonded, silica with a large average particle size is preferably used. As silica with a large average particle size, Sidistar R300 (made by Elkem), Sidistar T120U (made by Elkem), Admafine series (made by Admatechs), EXCELICA series (made by Tokuyama), etc. can be cited.

[0117] The average value of the product of "(particle size)×(roundness)" of the silica particles is preferably 17.5 nm or more, more preferably 20.0 nm or more, further preferably 30.0 nm or more, particularly preferably 50.0 nm or more, and most preferably 70.0 nm or more, and is preferably 500 μm or less, more preferably 300 μm or less, further preferably 100 μm or less, particularly preferably 50 μm or less, and most preferably 30 μm or less.

[0118] The average particle size of silica is preferably 25.0 nm or more, more preferably 30.0 nm or more, further preferably 40.0 nm or more, particularly preferably 60.0 nm or more, and most preferably 80.0 nm or more, and is preferably 500 μm or less, more preferably 300 μm or less, and further preferably 100 μm or less.

[0119] The average circularity of silica is preferably 0.80 or more, more preferably 0.85 or more. The upper limit of the theoretical circularity is 1.

[0120] The "average particle size" of silica can be determined by adsorbing silica particles onto a polyethylene terephthalate (PET) film, coating the film using platinum sputtering, and performing image analysis on a scanning electron microscope (SEM) photograph of the silica particles in the coated film. In the image analysis, after processing the SEM photograph to remove noise and binarization, 100 particles are randomly selected from the processed image, and the average diameter of the silica particles observed in the two-dimensional image with a depth of field of 1μm to 2μm is measured. Here, for a circular two-dimensional shape, "diameter" corresponds to the diameter (not the radius). For a non-circular two-dimensional shape having an area S, the "diameter" is considered to be equivalent to the diameter of a circle, and is obtained by taking the square root of (4×S / π).

[0121] The "average roundness" of silica can be measured by adsorbing silica particles on a PET film, coating the film using platinum sputtering, and performing image analysis on a SEM photograph of the silica particles in the coated film. In the image analysis, after processing the SEM photograph to remove noise and binarize, 100 particles are randomly selected from the processed image, and the average roundness of the silica particles observed in a two-dimensional image with a depth of field of 1 μm to 2 μm is measured. The value of the "roundness" of a two-dimensional shape is defined as follows.

[0122] (circularity) = 4π × (area of ​​the binary two-dimensional cross-sectional image of the silica particle) / (periphery of the binary two-dimensional cross-sectional image of the silica particle) 2

[0123] The closer the roundness value is to 1, the closer the corresponding two-dimensional shape is to a perfect circle.

[0124] The "average value of the product of (particle size) x (roundness)" of silica can be measured by adsorbing silica particles on a PET film, coating the film using platinum sputtering, and performing image analysis on an SEM photograph of the silica particles in the coated film. In the image analysis, after processing the SEM photograph to remove noise and binarize, 100 particles are randomly selected from the processed image, and the average value of the product of "(particle size) x (roundness)" of the silica particles observed in a two-dimensional image with a depth of field of 1 μm to 2 μm is measured.

[0125] In the measurement of the average particle size, average circularity and average value of the product of "(particle size) × (circularity)" mentioned above, agglomerated particles are sometimes mistakenly counted as one large particle, and gray shadows in the particle image are not recognized as part of the particle. Therefore, only silica particles with clear outlines are selected as representative samples, and repeated silica particles are ignored.

[0126] From the viewpoint of appropriately adjusting the conductivity of the rubber layer and making the rubber layer and the fluororesin layer more firmly bonded, the content of silica in the rubber composition is preferably 5 to 100 parts by mass, more preferably 10 parts by mass or more, further preferably 15 parts by mass or more, and more preferably 50 parts by mass or less, further preferably 30 parts by mass or less, based on 100 parts by mass of the rubber.

[0127] (Crosslinking agent)

[0128] From the viewpoint of making the rubber layer and the fluororesin layer more firmly bonded, the rubber composition preferably further contains a crosslinking agent. As the crosslinking agent, a peroxide crosslinking agent or the like can be selected according to the purpose. The rubber composition preferably further contains a peroxide crosslinking agent.

[0129] The peroxide crosslinking agent is not particularly limited, and examples thereof include organic peroxides. As the organic peroxide, it is preferred that the substance easily generates peroxide radicals in the presence of heat or a redox system, and examples thereof include 1,1-bis(tert-butylperoxy)-3,5,5-trimethylcyclohexane, 2,5-dimethylhexane-2,5-dihydroxyperoxide, di-tert-butyl peroxide, tert-butylcumyl peroxide, dicumyl peroxide, α,α'-bis(tert-butylperoxy)-p-diisopropylbenzene, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di(tert-butylperoxy)-3-hexyne, benzoyl peroxide, tert-butylbenzene peroxide, 2,5-dimethyl-2,5-di(benzoylperoxide)hexane, tert-butylperoxymaleate, tert-butylperoxyisopropylcarbonate, etc. Among them, dialkyl compounds are more preferred.

[0130] Usually, the amount of the peroxide crosslinking agent used can be appropriately selected according to the amount of active -OO-, decomposition temperature, etc. The content of the peroxide crosslinking agent in the rubber composition is usually 0.1 to 15 parts by mass, preferably 0.3 parts by mass or more, more preferably 1.0 parts by mass or more, and preferably 5 parts by mass or less, more preferably 3 parts by mass or less, relative to 100 parts by mass of the rubber.

[0131] (Crosslinking aid)

[0132] When the crosslinking agent is a peroxide crosslinking agent, the rubber composition preferably contains a crosslinking aid. Examples of the crosslinking aid include triallyl cyanurate, trimethallyl isocyanurate, triallyl isocyanurate (TAIC), 1,3,5-triacryloylhexahydro-1,3,5-triazine, triallyl trimellitate, N,N'-m-phenylene bismaleimide, dipropargyl terephthalate, diallyl phthalate, tetraallyl terephthalamide, triallyl phosphate, bismaleimide, fluorinated triallyl isocyanurate (1,3,5-tris(2,3,3-trifluoro-2-propanediol)), and the like. Triallylphosphite, N,N-diallylacrylamide, 1,6-divinyldodecafluorohexane, hexaallylphosphoramide, N,N,N',N'-tetraallylphthalamide, N,N,N',N'-tetraallylmalonamide, trivinylisocyanurate, 2,4,6-trivinylmethyltrisiloxane, tris(5-norbornene-2-methylene)cyanurate, triallylphosphite, etc. Among them, triallylisocyanurate (TAIC) is preferred from the viewpoint of excellent crosslinking properties and physical properties of the crosslinked product.

[0133] The content of the crosslinking aid in the rubber composition is preferably 0.1 to 10 parts by mass, more preferably 1.0 part by mass or more, more preferably 7 parts by mass or less, and even more preferably 5 parts by mass or less, based on 100 parts by mass of the rubber.

[0134] (Other components of rubber composition)

[0135] The rubber composition may contain at least one compound selected from the group consisting of metal oxides, metal hydroxides, weak acid salts of alkali metals and weak acid salts of alkaline earth metals as an acid acceptor or as a compounding agent for improving the adhesion between the rubber layer and the fluororesin layer.

[0136] Examples of the above-mentioned metal oxides, metal hydroxides, weak acid salts of alkali metals and weak acid salts of alkaline earth metals include oxides, hydroxides, carbonates, carboxylates, silicates, borates, phosphites of metals of Group (II) of the Periodic Table, oxides, alkaline carbonates, alkaline carboxylates, alkaline phosphites, alkaline sulfites, etc. of metals of Group (IV) of the Periodic Table.

[0137] Specific examples of metal oxides, metal hydroxides, weak acid salts of alkali metals, and weak acid salts of alkaline earth metals include magnesium oxide, zinc oxide, magnesium hydroxide, barium hydroxide, magnesium carbonate, barium carbonate, calcium oxide (quicklime), calcium hydroxide (slaked lime), calcium carbonate, calcium silicate, calcium stearate, zinc stearate, calcium phthalate, calcium phosphite, tin oxide, basic tin phosphite, and the like.

[0138] When a peroxide crosslinking agent is used as the crosslinking agent, the content of the metal oxide, metal hydroxide, weak acid salt of alkali metal, and weak acid salt of alkaline earth metal is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, based on 100 parts by mass of the rubber. From the viewpoint of acid resistance, it is further preferred that these substances are not contained.

[0139] The rubber composition may contain additives commonly used in rubber compositions, such as fillers, processing aids, plasticizers, colorants, stabilizers, adhesion promoters, acid acceptors, anti-sticking agents, conductivity-imparting agents, thermal conductivity-imparting agents, surface non-adhesives, flexibility-imparting agents, heat resistance improvers, flame retardants and the like, as needed. It may also contain one or more conventional cross-linking agents or cross-linking accelerators different from those mentioned above.

[0140] (B) Fluororesin layer

[0141] The fluororesin layer is a layer formed of a fluororesin. In the present invention, the fluororesin refers to a partially crystalline fluoropolymer, which is a fluoroplastic. The fluororesin has a melting point and is thermoplastic.

[0142] The fluororesin forming the fluororesin layer of the laminate of the present invention is a fluororesin that can be melt-molded. "Melt-molded" means that the polymer can be melted and processed using conventional processing equipment such as an extruder and an injection molding machine. Therefore, the melt-molded fluororesin generally has a melt flow rate of 0.01 g / 10 minutes to 500 g / 10 minutes as measured by the measurement method described below.

[0143] As the fluororesin, a fluororesin having a low fuel permeability coefficient is preferred. The fuel permeability coefficient of the fluororesin is preferably 2.0 g·mm / m 2 / day or less, more preferably 1.5g·mm / m 2 / day or less, more preferably 0.8g·mm / m 2 / day or less, particularly preferably 0.55g·mm / m 2 / day or less, most preferably 0.5g·mm / m 2 When the fluororesin layer contains a fluororesin having a fuel permeability coefficient within the above range, the fluororesin layer exhibits excellent low fuel permeability, and the laminate can be suitably used as a fuel hose or the like.

[0144] The fuel permeation coefficient is a value calculated as follows: 18 mL of a mixed solvent of isooctane / toluene / ethanol (mixed isooctane, toluene, and ethanol in a volume ratio of 45:45:10) was placed in a well with an inner diameter of 1.5 mm. A fluororesin sheet (45 mm in diameter, 120 μm in thickness) made of the resin to be measured by the following method was placed in a 20 mm high SUS316 fuel permeability measurement cup, and the fuel permeability was calculated based on the mass change measured at 60°C.

[0145] (Method for producing fluororesin sheet)

[0146] The resin pellets were added to a mold with a diameter of 120 mm, placed in a press heated to 300°C, and melt-pressed at a pressure of about 2.9 MPa to obtain a fluororesin sheet with a thickness of 0.12 mm. The sheet was processed into a diameter of 45 mm and a thickness of 120 μm.

[0147] As the fluororesin, from the perspective of obtaining a laminate having excellent low fuel permeability, at least one selected from the group consisting of polytrifluorochloroethylene (PCTFE), CTFE-based copolymers and TFE / HFP / VdF copolymers is preferred. From the perspective of obtaining a laminate having better adhesion between the rubber layer and the fluororesin layer and excellent low fuel permeability, at least one selected from the group consisting of CTFE-based copolymers and TFE / HFP / VdF copolymers is more preferred. From the perspective of obtaining a laminate having better adhesion between the rubber layer and the fluororesin layer and excellent low fuel permeability and flexibility, a CTFE-based copolymer is further preferred.

[0148] In the TFE / HFP / VdF copolymer, since the fuel permeability is excellent if the VdF content is small, the copolymerization ratio (mol %) of TFE, HFP and VdF is preferably TFE / HFP / VdF=75-95 / 0.1-10 / 0.1-19, more preferably 77-95 / 1-8 / 1-17 (mol ratio), further preferably 77-95 / 2-8 / 2-15.5 (mol ratio), and most preferably 79-90 / 5-8 / 5-15 (mol ratio). In addition, the TFE / HFP / VdF copolymer may contain 0-20 mol % of other monomers. As other monomers, there can be mentioned at least one monomer selected from the group consisting of perfluoro(methyl vinyl ether), perfluoro(ethyl vinyl ether), perfluoro(propyl vinyl ether), chlorotrifluoroethylene, 2-chloropentafluoropropylene, perfluorinated vinyl ethers (for example, perfluoroalkoxy vinyl ethers such as CF3OCF2CF2CF2OCF=CF2), etc., perfluoroalkyl vinyl ethers, perfluoro-1,3-butadiene, trifluoroethylene, hexafluoroisobutylene, vinyl fluoride, ethylene, propylene and alkyl vinyl ethers, and preferably perfluoro(methyl vinyl ether), perfluoro(ethyl vinyl ether) and perfluoro(propyl vinyl ether).

[0149] PCTFE is a homopolymer of chlorotrifluoroethylene.

[0150] The CTFE-based copolymer preferably comprises a copolymer unit derived from CTFE (CTFE unit) and a copolymer unit derived from a monomer selected from TFE, HFP, PAVE, VdF, vinyl fluoride, hexafluoroisobutylene, and the formula: CH2=CX 3 (CF2) n X 4 (Where X 3 H or F, X 4 The CTFE copolymer is preferably a fully halogenated polymer.

[0151] As a CTFE-based copolymer, it is more preferred to include a CTFE unit and a copolymerization unit of at least one monomer selected from the group consisting of TFE, HFP and PAVE, and it is further preferred to be substantially composed of only these copolymerization units. In addition, from the perspective of low fuel permeability, it is preferred not to include a monomer having a CH bond such as ethylene, vinylidene fluoride, or vinyl fluoride.

[0152] A perhalogen polymer containing no monomer having a CH bond is generally difficult to adhere to rubber (particularly fluororubber), but according to the configuration of the present invention, even when the fluororesin contains a perhalogen polymer, the interlayer adhesion between the rubber layer and the fluororesin layer is strong.

[0153] The CTFE-based copolymer preferably has 10 mol % to 90 mol % of CTFE units based on all monomer units.

[0154] The CTFE-based copolymer particularly preferably contains a CTFE unit, a TFE unit, and a monomer (α) unit derived from a monomer (α) copolymerizable with these units.

[0155] "CTFE unit" and "TFE unit" are respectively the part derived from CTFE (-CFCl-CF2-) and the part derived from TFE (-CF2-CF2-) in the molecular structure of the CTFE-based copolymer. Similarly, the above-mentioned "monomer (α) unit" is the part formed by the addition of monomer (α) in the molecular structure of the CTFE-based copolymer.

[0156] The monomer (α) is not particularly limited as long as it is a monomer copolymerizable with CTFE and TFE, and examples thereof include ethylene (Et), vinylidene fluoride (VdF), CF2=CF-ORf 2 (Where Rf 2 is a perfluoroalkyl group having 1 to 8 carbon atoms) PAVE, CX 5 X 6 =CX 7 (CF2)n X 8 (Where X 5 , X 6 and X 7 are the same or different and are hydrogen or fluorine atoms; X 8 is a hydrogen atom, a fluorine atom or a chlorine atom; n is an integer from 1 to 10), a vinyl monomer represented by CF2=CF-O-Rf 3 (Where Rf 3 It is an alkyl perfluorovinyl ether derivative represented by a perfluoroalkyl group having 1 to 5 carbon atoms.

[0157] As the above-mentioned alkyl perfluorovinyl ether derivative, preferably Rf 3 It is a perfluoroalkyl group having 1 to 3 carbon atoms, and more preferably CF2=CF-OCF2-CF2CF3 (PPVE).

[0158] Among these, the monomer (α) is preferably at least one selected from the group consisting of PAVE, the above-mentioned vinyl monomers and alkyl perfluorovinyl ether derivatives, more preferably at least one selected from the group consisting of PAVE and HFP, and particularly preferably PAVE.

[0159] Regarding the ratio of CTFE units to TFE units in the CTFE-based copolymer, the CTFE units are 15 mol% to 90 mol%, and the TFE units are 85 mol% to 10 mol%, more preferably 20 mol% to 90 mol% of the CTFE units and 80 mol% to 10 mol% of the TFE units. In addition, it is also preferred that the CTFE units are 15 mol% to 25 mol% and the TFE units are 85 mol% to 75 mol%.

[0160] In the CTFE copolymer, the total content of CTFE units and TFE units is preferably 90 mol% to 99.9 mol%, and the content of monomer (α) units is 0.1 mol% to 10 mol%. When the content of monomer (α) units is less than 0.1 mol%, the moldability, environmental stress cracking resistance and fuel cracking resistance are likely to deteriorate; when it exceeds 10 mol%, there is a tendency for low fuel permeability, heat resistance and mechanical properties to deteriorate.

[0161] As the fluororesin, from the aspects of low fuel permeability and adhesion, at least one selected from the group consisting of PCTFE, CTFE / TFE / PAVE copolymer and TFE / HFP / VdF copolymer is more preferred, at least one selected from the group consisting of CTFE / TFE / PAVE copolymer and TFE / HFP / VdF copolymer is further preferred, and CTFE / TFE / PAVE copolymer is particularly preferred.

[0162] In the CTFE / TFE / PAVE copolymer, the above-mentioned PAVE may include perfluoro(methyl vinyl ether) (PMVE), perfluoro(ethyl vinyl ether) (PEVE), perfluoro(propyl vinyl ether) (PPVE), perfluoro(butyl vinyl ether), etc., among which at least one selected from the group consisting of PMVE, PEVE and PPVE is preferred.

[0163] In the CTFE / TFE / PAVE copolymer, the PAVE unit preferably accounts for 0.5 mol% or more and preferably 5 mol% or less of all monomer units.

[0164] The structural units such as CTFE units are obtained by 19 The value obtained by F-NMR analysis.

[0165] The fluororesin may be a fluororesin having at least one reactive functional group selected from the group consisting of a carbonyl group, a hydroxyl group, a heterocyclic group and an amino group introduced into the main chain terminal and / or the side chain of the polymer.

[0166] In the present invention, "carbonyl" is a carbonyl divalent group consisting of a carbon-oxygen double bond, which is represented by a group represented by -C(=O)-. The reactive functional group containing a carbonyl group is not particularly limited, and examples thereof include carbonate groups, carboxylic acid halides (haloformyl groups), formyl groups, carboxyl groups, ester bonds (-C(=O)O-), anhydride bonds (-C(=O)OC(=O)-), isocyanate groups, amide groups, imide groups (-C(=O)-NH-C(=O)-), carbamate bonds (-NH-C(=O)O-), carbamoyl groups (NH2-C(=O)-), carbamoyloxy groups (NH2-C(=O)O-), urea groups (NH2-C(=O)-NH-), aminooxalyl groups (NH2-C(=O)-C(=O)-), and functional groups containing a carbonyl group as a part of the chemical structure.

[0167] In an amide group, an imide group, a urethane bond, a carbamoyl group, a carbamoyloxy group, a urea group, an aminooxalyl group or the like, a hydrogen atom bonded to a nitrogen atom thereof may be substituted with a hydrocarbon group such as an alkyl group.

[0168] From the perspective of easy introduction, moderate heat resistance of the fluororesin and good adhesion at relatively low temperatures, the reactive functional group is preferably an amide group, a carbamoyl group, a hydroxyl group, a carboxyl group, a carbonate group, a carboxylic acid halide group, or an acid anhydride bond, and more preferably an amide group, a carbamoyl group, a hydroxyl group, a carbonate group, a carboxylic acid halide group, or an acid anhydride bond.

[0169] Fluororesin can be obtained by conventionally known polymerization methods such as suspension polymerization, solution polymerization, emulsion polymerization, bulk polymerization, etc. In the above polymerization, various conditions such as temperature and pressure, polymerization initiator and other additives can be appropriately set according to the composition and amount of fluororesin.

[0170] The melting point of the fluororesin is not particularly limited, but is preferably 160° C. to 270° C. The melting point of the fluororesin is determined by heating the sample at a rate of 10° C. / min using a DSC apparatus (manufactured by SEIKO) and determining the temperature corresponding to the maximum value in the heat of fusion curve during the heating.

[0171] In addition, the molecular weight of the fluororesin is preferably within a range in which the obtained laminate can exhibit good mechanical properties, low fuel permeability, etc. For example, when the melt flow rate (MFR) is used as an indicator of the molecular weight, the MFR at any temperature in the usual molding temperature range of the fluororesin, i.e., about 230°C to 350°C, is preferably 0.5 g / 10 min to 100 g / 10 min, more preferably 1 g / 10 min to 50 g / 10 min, and further preferably 2 g / 10 min to 35 g / 10 min. For example, when the fluororesin is PCTFE, CTFE-based copolymers, or TFE / HFP / VdF copolymers, the MFR is measured at 297°C.

[0172] The MFR can be determined by measuring, for example, the weight (g) of a polymer flowing out from a nozzle having a diameter of 2 mm and a length of 8 mm under a load of 5 kg at 297° C. and a unit time (10 minutes) using a melt flow indexer (manufactured by Toyo Seiki Seisaku-sho, Ltd.).

[0173] The fluororesin layer may contain one type of such fluororesins, or may contain two or more types.

[0174] In addition, when the fluororesin is a perhalogen polymer, the chemical resistance and low fuel permeability are more excellent. A perhalogen polymer is a polymer in which halogen atoms are bonded to all carbon atoms constituting the main chain of the polymer.

[0175] The fluororesin layer may further contain various fillers such as inorganic powder, glass fiber, carbon powder, carbon fiber, metal oxide, etc., depending on the purpose and application, within a range that does not impair the performance.

[0176] For example, in order to further reduce the fuel permeability, smectite-based layered clay minerals such as montmorillonite, beidellite, saponite, nontronite, hectorite, sauconite, and stevensite, or micro-layered minerals with a high aspect ratio such as mica may be added.

[0177] (laminated body)

[0178] The thickness of the rubber layer is not limited, but is preferably 100 μm or more, for example. The upper limit of the thickness of the rubber layer is, for example, 5000 μm.

[0179] The thickness of the fluororesin layer is not limited, but is preferably 10 μm or more, for example. The upper limit of the thickness of the fluororesin layer is, for example, 1000 μm.

[0180] The bonding strength between the rubber layer and the fluororesin layer in the laminate is preferably 3 N / cm or more, more preferably 4 N / cm or more, further preferably 5 N / cm or more, particularly preferably 6 N / cm or more.

[0181] The bonding strength is a value measured as follows: the laminate is cut into strips of 10 mm in width × 40 mm in length × 3 to prepare test pieces. For the test pieces, in order to exclude the influence of the bonding strength at the boundary surface between the rubber layer and the fluororesin layer and measure only the bonding strength of the bonding surface, the interface between the rubber layer and the fluororesin layer is slowly pulled apart once by hand to increase a gripping edge of 2 mm to 3 mm, and then a peeling test is carried out at a tensile speed of 50 mm / min at 25°C using an Autograph (AGS-J 5kN manufactured by Shimadzu Corporation) according to the method described in JIS-K-6256 (Adhesion test method for vulcanized rubber), and the peeling pattern is observed and measured. The obtained value is the above-mentioned bonding strength.

[0182] In the laminate of the present invention, the rubber layer and the fluororesin layer are preferably directly bonded, and more preferably directly cross-linked and bonded. Such a laminate is obtained by laminating an uncross-linked rubber layer and a fluororesin layer and then performing a cross-linking treatment. The laminate of the present invention may be a cross-linked laminate.

[0183] The cross-linking treatment can adopt the cross-linking method and conditions of the rubber composition known in the art. For example, there are the following methods: a method of cross-linking an uncross-linked laminate for a long time; a method of subjecting the uncross-linked laminate to a heat treatment for a short time as a pretreatment (cross-linking also occurs), followed by cross-linking for a long time. Among these, the method of subjecting the uncross-linked laminate to a heat treatment for a short time as a pretreatment, followed by cross-linking for a long time is preferred, because the adhesion between the rubber layer and the fluororesin layer can be easily obtained by the pretreatment, and the rubber layer has been cross-linked in the pretreatment and the shape has been stabilized, so various methods of maintaining the laminate can be selected in the subsequent cross-linking.

[0184] The conditions for the crosslinking treatment are not particularly limited, and the treatment can be carried out under normal conditions, preferably at 140° C. to 180° C. for 2 minutes to 80 minutes using steam, pressure, oven, air bath, infrared, microwave, lead-coated crosslinking, etc. More preferably, it is carried out at 150° C. to 170° C. for 5 minutes to 60 minutes. The crosslinking treatment can be carried out by primary crosslinking and secondary crosslinking.

[0185] The laminate of the present invention can be suitably produced by a method for producing a laminate, for example, comprising the steps of mixing rubber and carbon black to obtain a rubber composition, laminating an uncrosslinked rubber layer obtained by molding the rubber composition and a fluororesin layer, and subjecting the laminated uncrosslinked rubber layer and fluororesin layer to a crosslinking treatment. In the above-mentioned production method, the conditions for the crosslinking treatment are the same as those described above.

[0186] The rubber and carbon black can be mixed by kneading the rubber and carbon black using a commonly used rubber kneading device, for example.

[0187] As the rubber kneading apparatus, a roll, a kneader, a Banbury mixer, an internal mixer, a twin-screw extruder, etc. can be used.

[0188] During the mixing, in addition to the rubber and carbon black, other additives such as a basic polyfunctional compound, polytetrafluoroethylene, silica, a crosslinking agent, and a crosslinking aid may be mixed together as necessary.

[0189] The mixing temperature is, for example, 20° C. to 200° C. The mixing time is, for example, 2 minutes to 80 minutes.

[0190] The lamination of the uncrosslinked rubber layer and the fluororesin layer may be any one of a method of laminating the uncrosslinked rubber layer and the fluororesin layer by separately molding the uncrosslinked rubber layer and the fluororesin layer by means of crimping or the like, a method of simultaneously molding the uncrosslinked rubber layer and laminating the uncrosslinked rubber layer and a method of coating the uncrosslinked rubber layer with a fluororesin to form the fluororesin layer.

[0191] In the method of laminating the uncrosslinked rubber layer and the fluororesin layer by means of pressure bonding or the like after molding them separately, separate molding methods for the rubber composition and the fluororesin may be used.

[0192] The uncrosslinked rubber layer can be produced by molding the rubber composition into various shapes such as sheets and tubes using methods such as heat compression molding, transfer molding, extrusion molding, injection molding, calendaring molding, and coating. During molding, a commonly used polymer molding machine, such as an injection molding machine, a blow molding machine, an extrusion molding machine, and various coating devices can be used to produce a laminate in various shapes such as sheets and tubes. Among these, extrusion molding is preferred from the perspective of excellent productivity.

[0193] The fluororesin layer can be made by molding the fluororesin into various shapes such as sheets and tubes using compression molding, extrusion molding, injection molding, calendering, coating (including powder coating) and the like. In the molding, a molding machine of a commonly used polymer, such as an injection molding machine, a blow molding machine, an extrusion molding machine, various coating devices, etc., can be used to manufacture laminates of various shapes such as sheets and tubes. Among these, extrusion molding is preferred from the aspect of excellent productivity.

[0194] As a method for simultaneously molding and laminating an uncrosslinked rubber layer and a fluororesin layer, a method for molding and laminating simultaneously using a rubber composition forming a rubber layer and a fluororesin forming a fluororesin layer by a multilayer compression molding method, a multilayer transfer molding method, a multilayer extrusion molding method, a multilayer injection molding method, a double-layer molding method, etc. can be cited. In this method, since the uncrosslinked rubber layer as an uncrosslinked molded body can be laminated simultaneously with the fluororesin layer, it is not particularly necessary to make the uncrosslinked rubber layer and the fluororesin layer close together, and this method is also suitable for obtaining a firm bonding in a subsequent crosslinking process. In the case of insufficient close fitting, a close fitting process such as polishing can be performed. Among these, from the aspect of excellent productivity, a multilayer extrusion molding method is preferred.

[0195] (Laminate structure of laminate)

[0196] The laminate of the present invention comprises the rubber layer (A) and the fluororesin layer (B).

[0197] The laminate of the present invention may have a two-layer structure of a rubber layer (A) and a fluororesin layer (B), or may have the rubber layer (A) laminated on both sides of the fluororesin layer (B), or may have the fluororesin layer (B) laminated on both sides of the rubber layer (A).

[0198] For example, a three-layer structure of rubber layer (A) - fluororesin layer (B) - rubber layer (A) or fluororesin layer (B) - rubber layer (A) - fluororesin layer (B) may be used.

[0199] In addition, the multilayer structure may be a structure of three or more layers of a polymer layer (C) other than a rubber layer (A) and a fluororesin layer (B) bonded together, and a polymer layer (D) may be provided on one or both sides of a multilayer structure of three layers of a polymer layer (C) other than a rubber layer (A) and a fluororesin layer (B) bonded together. The polymer layer (C) and the polymer layer (D) may be the same or different.

[0200] The laminate of the present invention may have a polymer layer (C) on one side or both sides of the three-layer structure of rubber layer (A)-fluororesin layer (B)-rubber layer (A).

[0201] As the polymer layer (C) or (D), a rubber layer (C1) or (D1) other than the rubber layer (A) can be used. As the rubber layer (C1) or (D1), a non-fluororubber layer (C1a) or (D1a) formed of non-fluororubber can be mentioned. Non-fluororubber is excellent in cold resistance and cost, and is therefore preferred. The non-fluororubber layer (C1a) and the non-fluororubber layer (D1a) can be formed of the same non-fluororubber or different non-fluororubbers.

[0202] The laminate of the present invention may be laminated in the order of rubber layer (A) - fluororesin layer (B) - non-fluororubber layer (C1a).

[0203] The laminate of the present invention may further include a non-fluororubber layer (D1a) and be laminated in the order of non-fluororubber layer (D1a) - rubber layer (A) - fluororesin layer (B) - non-fluororubber layer (C1a), in the order of rubber layer (A) - fluororesin layer (B) - non-fluororubber layer (D1a) - non-fluororubber layer (C1a), or in the order of rubber layer (A) - fluororesin layer (B) - non-fluororubber layer (C1a) - non-fluororubber layer (D1a).

[0204] As specific examples of non-fluorine rubber, for example, diene rubbers such as nitrile rubber (NBR) or its hydrogenated product (HNBR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), butadiene rubber (BR), natural rubber (NR), isoprene rubber (IR), ethylene-propylene terpolymer rubber, silicone rubber, butyl rubber, epichlorohydrin rubber, acrylic rubber, chlorinated polyethylene (CPE), polymer blends of nitrile rubber and vinyl chloride (PVC-NBR), ethylene propylene diene rubber (EPDM), chlorosulfonated polyethylene (CSM), etc. can be cited. In addition, rubbers obtained by mixing these non-fluorine rubbers and fluorine rubbers in any proportion can also be cited.

[0205] As the non-fluororubber, diene rubber or epichlorohydrin rubber is preferred from the aspects of good heat resistance, oil resistance, weather resistance and extrusion moldability. NBR, HNBR or epichlorohydrin rubber is more preferred. The rubber layer (C1) is preferably composed of NBR, HNBR or epichlorohydrin rubber.

[0206] In addition, from the viewpoint of weather resistance and cost, the rubber layer (D1) is preferably composed of nitrile rubber, epichlorohydrin rubber, chlorinated polyethylene (CPE), a polymer blend of nitrile rubber and vinyl chloride (PVC-NBR), ethylene propylene diene rubber (EPDM), acrylic rubber, or a mixture thereof. It should be noted that a crosslinking agent or other compounding agents may be compounded in the uncrosslinked rubber composition forming the rubber layers (C1) and (D1).

[0207] In the above-mentioned layer structure, the laminate of the present invention is preferably configured in such a manner that the rubber layer (A) forms at least one surface of the laminate. In the laminate of the present invention, the rubber layer (A) has conductivity, and the rubber layer (A) and the fluororesin layer (B) are firmly bonded. Therefore, by using the rubber layer (A) to form at least one surface of the laminate, it is possible to effectively prevent the laminate from being charged while imparting flexibility, and by the fluororesin layer (B) firmly bonded to the rubber layer (A), other characteristics such as low fuel permeability can be sufficiently imparted to the laminate.

[0208] Next, the layered structure of the layered product of the present invention will be described in more detail.

[0209] (1) Two-layer structure of rubber layer (A) and fluororesin layer (B)

[0210] This is a basic structure. In the past, when the fluororesin layer (B) and the rubber layer (A) were stacked, the bonding between the layers (fluororubber layer-fluororesin layer) was insufficient, so it was necessary to perform surface treatment on the resin side, or to apply an adhesive between the layers, or to fix them by winding a tape film, etc., which made the process complicated. However, the present invention does not require the combination of such complicated processes, but produces cross-linked bonding through cross-linking to obtain chemically strong bonding.

[0211] (2) Three-layer structure of rubber layer-fluororesin layer (B)-rubber layer

[0212] It has a three-layer structure of rubber layer (A) - fluororesin layer (B) - rubber layer (A) and a three-layer structure of rubber layer (A) - fluororesin layer (B) - rubber layer (C1).

[0213] When sealing is required, for example, for a joint of a fuel pipe, rubber layers are preferably arranged on both sides to maintain sealing. The inner and outer rubber layers may be of the same type or different types.

[0214] In the case of a three-layer structure of rubber layer (A) - fluororesin layer (B) - rubber layer (C1), the rubber layer (C1) is preferably a layer formed of nitrile rubber, hydrogenated nitrile rubber, epichlorohydrin rubber, or a mixture of nitrile rubber and acrylic rubber.

[0215] In addition, by making the fuel piping a three-layer structure of rubber layer (A)-fluororesin layer (B)-rubber layer (C1), providing a fluororubber layer as the rubber layer (C1), and making the rubber layer (C1) the inner layer of the piping, chemical resistance and low fuel permeability can be improved.

[0216] (3) Three-layer structure of resin layer-rubber layer (A)-resin layer

[0217] A three-layer structure of fluororesin layer (B) - rubber layer (A) - fluororesin layer (B) can be mentioned. The inner and outer resin layers may be of the same type or different types.

[0218] (4) Three-layer structure of fluororesin layer (B) - rubber layer (A) - rubber layer (C1)

[0219] (5) 4-layer structure or above

[0220] In addition to the three-layer structure of (2) to (4), any rubber layer (A) or rubber layer (C1) and fluororesin layer (B) may be further laminated according to the purpose. In addition, a layer such as a metal foil may be provided, and an adhesive layer may be interposed between the rubber layer (A) and the fluororesin layer (B).

[0221] Furthermore, it may be laminated with a polymer layer (C) to form a liner body.

[0222] It should be noted that the thickness, shape, etc. of each layer may be appropriately selected according to the purpose of use, form of use, and the like.

[0223] Furthermore, in order to improve the pressure resistance, a reinforcing layer such as reinforcing yarn may be appropriately provided.

[0224] The laminate of the present invention has excellent low fuel permeability, as well as heat resistance, oil resistance, fuel oil resistance, LLC resistance, steam resistance, weather resistance, and ozone resistance, and can fully withstand use under severe conditions and can be used in various applications.

[0225] For example, it can be used as the engine body, main motion system, valve system, lubrication / cooling system, fuel system, intake / exhaust system, etc. of automobile engines; the transmission system of the drive system; the control system, brake system, etc. of the chassis; basic electrical components of electrical equipment, control system electrical components, equipment electrical components, etc., and as gaskets or non-contact and contact type seals (self-tightening seals, piston rings, open ring seals, mechanical seals, oil sealing devices, etc.) that require heat resistance, oil resistance, fuel oil resistance, LLC resistance, and steam resistance, and has suitable properties for seals, bellows, diaphragms, hoses, pipes, wires, etc.

[0226] Specifically, it can be used for the following purposes.

[0227] Gaskets such as cylinder head gaskets, cylinder head cover gaskets, oil pan gaskets, and general gaskets of the engine body; seals such as O-rings, gaskets, and timing belt cover gaskets; hoses such as control hoses; vibration-proof rubber for engine brackets; sealing materials for high-pressure valves in hydrogen storage systems, etc.

[0228] Crankshaft seals, camshaft oil seals and other shaft sealing devices of the main motion system.

[0229] Valve stem seals for engine valves in valvetrain systems, etc.

[0230] Oil cooler hose, oil return hose, sealing gasket, etc. of the oil cooler of the lubrication and cooling system; water hose around the radiator, vacuum pump oil hose, etc. of the vacuum pump.

[0231] Oil seals, diaphragms, valves, etc. of fuel pumps in fuel systems; fuel hoses such as neck hoses, fuel supply hoses, fuel return hoses, and evaporator hoses; built-in hoses, packing seals, tank gaskets, built-in fuel pump assemblies, etc. of fuel tanks; pipe bodies or connector O-rings, etc. of fuel piping; injector gaskets, injector seals, injector O-rings, pressure regulator diaphragms, check valves, etc. of fuel injection devices; needle valves, accelerator pump pistons, flange gaskets, control hoses, etc. of carburetors; valve seals, diaphragms, etc. of composite air control devices (CAC). Among them, it is suitable as a fuel hose and a built-in hose of a fuel tank.

[0232] Intake manifold gaskets and exhaust manifold gaskets of the intake and exhaust system manifolds; diaphragms, control hoses, emission control hoses, etc. of EGR (exhaust gas recirculation); diaphragms, etc. of BPT; afterburning prevention valve seals of AB valves; throttle body gaskets of throttle valves, turbine oil hoses (supply) and turbine oil hoses (return oil) of turbochargers, turbine air hoses, intercooler hoses, turbine shaft seals, etc.

[0233] Transmission system transmission-related bearing seals, oil seals, O-rings, gaskets, torque converter hoses, etc.; AT transmission oil hoses, ATF hoses, O-rings, gaskets, etc.

[0234] Power steering oil hose for control systems, etc.

[0235] Oil seals, O-rings, gaskets, brake oil hoses, etc. of the brake system, atmospheric valves, vacuum valves, diaphragms, etc. of vacuum boosters, piston cups (rubber cups) of master cylinders, etc.; inner diameter seals, protective covers, etc.

[0236] Insulators or sheaths of wires (wiring harnesses) that are basic electrical components; pipes that are external components of wiring harnesses, etc.

[0237] Covering materials for various sensor lines of control system electrical components, etc.

[0238] O-rings, gaskets, radiator hoses, wiper blades, etc. for car air conditioners equipped with electrical components.

[0239] In addition to automotive applications, the present invention can be suitably used in applications such as: oil-resistant, chemical-resistant, heat-resistant, steam-resistant, or weather-resistant gaskets, O-rings, hoses, other sealing materials, diaphragms, and valves in transmission mechanisms of ships, aircraft, etc.; and similar gaskets, O-rings, sealing materials, diaphragms, valves, hoses, rollers, tubes, chemical-resistant coatings, and linings in chemical equipment; fuel pipes and hoses used in small equipment such as lawn mowers; hoses or gaskets in the chemical processing field; similar gaskets, O-rings, hoses, sealing materials, belts, diaphragms, valves, rollers, and tubes in food factory equipment and food equipment (including household products); similar gaskets, O-rings, hoses, sealing materials, diaphragms, valves, and tubes in nuclear power plant equipment; similar gaskets, O-rings, hoses, sealing materials, diaphragms, valves, and tubes in OA equipment and general industrial parts; and rollers and plates of PPC copiers. For example, since the stopper rubber material of the PTFE diaphragm has poor sliding properties, there is a problem of wear or breakage during use. However, by using the laminate of the present invention, this problem can be improved and it can be used appropriately.

[0240] In addition, in the use of food rubber sealing materials, the previous rubber sealing materials have the problem of smell or rubber fragments being mixed into the food, but by using the laminate of the present invention, this problem can be improved and can be used appropriately. When the rubber material is used as a sealing material for piping using a rubber sealing material solvent for medical and chemical purposes, the rubber material has the problem of being swollen by the solvent, but by using the laminate of the present invention, this problem can be improved by covering the resin. In the general industrial field, in order to improve the strength, sliding property, chemical resistance, and permeability of the rubber material, it can be appropriately used for example in rubber rollers, O-rings, gaskets, sealing materials, etc. In particular, in the use of gaskets for lithium ion batteries, it can maintain both chemical resistance and sealing properties, so it can be appropriately used. It can be appropriately used in other uses that require sliding properties based on low friction.

[0241] In addition, as medical applications, suppositories, bottle cap seals, can seals, medical tapes, medical pads, syringe seals, percutaneous absorption drug substrates, nozzles for baby bottles, etc., medical bags, catheters, infusion sets, mixing tubes, bottle cap pads, vacuum blood collection tube caps, syringe gaskets, infusion tubes, gaskets and caps for medical equipment, syringe chips, grommets, blood collection tube caps, cap seals, gaskets, O-rings, sheath introducers, dilators, guide sheaths, blood circuits, artificial heart-lung circuits, rotational atherectomy intervention Tubes for therapeutic instruments (Rotablator), indwelling needles, infusion sets, infusion tubes, closed infusion systems, infusion bags, blood bags, blood component separation belts, tubes for blood component separation bags, artificial blood vessels, arterial cannulas, support frames, protective tubes for endoscope treatment devices, endoscope body tubes, endoscope top outer sleeves, catheters for pharyngeal passage, tubes for coronary artery bypass surgery, intestinal obstruction tubes, tubes for percutaneous transhepatic biliary drainage, external tubes for electrosurgical knives, external tubes for ultrasonic knives, external tubes for stripping forceps, bags for cell culture, etc.

[0242] Examples of offshore molded products to which the laminate of the present invention can be applied include pipes and hoses for offshore oil fields (including injection pipes and crude oil transportation pipes).

[0243] Among these, the laminate is particularly suitable for use as a tube or a hose. That is, the laminate is preferably a tube or a hose. Among the tubes or hoses, from the aspects of heat resistance and low fuel permeability, it can be appropriately used as a fuel pipe or hose for automobiles.

[0244] The tube or hose of the present invention preferably has a rubber layer (A) as the innermost layer. Since the rubber layer (A) has conductivity, the use of the rubber layer (A) as the innermost layer improves the flexibility of the laminate, and even when static electricity is generated due to the flow of fluid in the tube or hose, the tube or hose can be less likely to be charged, and by having a fluororesin layer (B) firmly bonded to the rubber layer (A), other properties such as low fuel permeability can be improved.

[0245] Although the embodiments have been described above, it will be understood that various changes in form and details may be made without departing from the spirit and scope of the claims.

[0246] <1> According to a first aspect of the present invention, there is provided a laminate comprising a rubber layer (A) and a fluororesin layer (B) laminated on the rubber layer (A), wherein:

[0247] The rubber layer (A) is a conductive layer, and is formed of a rubber composition containing rubber and carbon black, wherein the content of the carbon black in the rubber composition is 1.0 to 100 parts by mass relative to 100 parts by mass of the rubber, and the nitrogen adsorption specific surface area of ​​the carbon black is 140 m 2 / g or less,

[0248] The fluororesin layer (B) is formed of a melt-moldable fluororesin.

[0249] <2> According to a second aspect of the present invention, there is provided a laminate according to the first aspect, wherein the carbon black has an average primary particle size of 28 nm or more.

[0250] <3> According to a third aspect of the present invention, there is provided the laminate according to the first aspect or the second aspect, wherein the content of the carbon black exceeds 8.0 parts by mass based on 100 parts by mass of the rubber.

[0251] <4> According to a fourth aspect of the present invention, there is provided a laminate according to any one of the first to third aspects, wherein the rubber is fluororubber.

[0252] <5> According to a fifth aspect of the present invention, there is provided a laminate according to any one of the first to fourth aspects, wherein the fuel permeability coefficient of the fluororesin is 2.0 g·mm / m 2 / day or less.

[0253] <6> According to a sixth aspect of the present invention, there is provided a laminate according to any one of the first to fifth aspects, wherein the fluororesin is at least one selected from the group consisting of chlorotrifluoroethylene-based copolymers and tetrafluoroethylene / hexafluoropropylene / vinylidene fluoride copolymers.

[0254] <7> According to the seventh aspect of the present invention, a laminate based on any one of the first to sixth aspects is provided, wherein the rubber composition further contains a basic polyfunctional compound, and the content of the polyfunctional compound in the rubber composition is 0.1 to 10 parts by mass relative to 100 parts by mass of the rubber.

[0255] <8> According to an eighth aspect of the present invention, there is provided a laminate according to any one of the first to seventh aspects, wherein the rubber composition further contains a peroxide cross-linking agent.

[0256] <9> According to a ninth aspect of the present invention, there is provided a laminate according to any one of the first to eighth aspects, wherein the rubber composition further contains polytetrafluoroethylene, and the specific surface area of ​​the polytetrafluoroethylene is less than 8 m 2 / g, the average particle size of the polytetrafluoroethylene is 0.01 μm to 1000 μm, and the melt viscosity of the polytetrafluoroethylene at 380°C is 1×10 1 Pa·s~7×10 5 Pa·s.

[0257] <10>According to the 10th aspect of the present invention, there is provided a laminate based on any one of the 1st to 9th aspects, wherein the rubber composition further contains silica, and the average value of the product of "(particle size) × (roundness)" of the silica is 17.5 nm or more and 500 μm or less.

[0258] <11>According to the 11th aspect of the present invention, there is provided a laminate based on any one of the 1st to 10th aspects, wherein the rubber layer (A) and the fluororesin layer (B) are crosslinked and bonded.

[0259] <12>According to the 12th aspect of the present invention, there is provided a laminate based on any one of the 1st to 11th aspects, wherein the bonding strength between the rubber layer (A) and the fluororesin layer (B) is 5 N / cm or more.

[0260] <13>According to the 13th aspect of the present invention, there is provided a laminate based on any one of the 1st to 12th aspects, wherein the laminate is a tube or a hose.

[0261] Examples

[0262] Next, examples are given to illustrate the embodiments of the present invention, but the present invention is not limited to the described examples.

[0263] The respective numerical values in the examples were measured by the following methods.

[0264] <Composition of CTFE / TFE / PPVE copolymer>

[0265] By 19 F-NMR analysis was performed for measurement.

[0266] <Melt flow rate (MFR) of CTFE / TFE / PPVE copolymer>

[0267] Regarding the MFR of the CTFE / TFE / PPVE copolymer, using a melt flow index measuring instrument (manufactured by Toyo Seiki Seisaku-sho, Ltd.), the weight (g) of the polymer flowing out from a nozzle with a diameter of 2 mm and a length of 8 mm per unit time (10 minutes) under a load of 5 kg at 297 °C was measured.

[0268] <Fuel permeation coefficient>

[0269] The pellets of the CTFE / TFE / PPVE copolymer were added to a mold with a diameter of 120 mm and placed in a press heated to 300 °C. Melting pressing was carried out at a pressure of about 2.9 MPa to obtain a sheet with a thickness of 0.12 mm. The obtained sheet was processed into a sheet with a diameter of 45 mm and a thickness of 120 μm. CE10 (a fuel obtained by mixing 10% by volume of ethanol in a mixture of isooctane and toluene with a volume ratio of 50:50) with a volume of 18 mL was put into a SUS316 permeation coefficient measurement cup with an inner diameter and a height of 20 mm, and the obtained sheet was added. The mass change at 60 °C was measured up to 1000 hours. The fuel permeation coefficient (g·mm / m 2 / day) was calculated from the mass change per unit time (the part where the mass change at the initial stage of measurement was constant), the surface area of the sheet in the contact liquid part, and the thickness of the sheet.

[0270] <Average particle size of PTFE>

[0271] Using a laser diffraction particle size distribution measuring device (manufactured by Japan Laser Co., Ltd.), without using a cascade, the particle size distribution was measured at a pressure of 0.1 MPa and a measurement time of 3 seconds. The value corresponding to 50% of the cumulative particle size distribution obtained was taken as the average particle size.

[0272] <Specific surface area of PTFE>

[0273] The measurement was carried out by the BET method using a surface analyzer (trade name: BELSORP-miniII, manufactured by Microtrac BEL Co., Ltd.). It should be noted that a mixed gas of 30% nitrogen and 70% helium was used as the carrier gas, and liquid nitrogen was used for cooling.

[0274] <Melting point of PTFE>

[0275] Using a differential scanning calorimeter RDC220 (DSC) manufactured by SII Nanotechnology Inc., the temperature was calibrated in advance using indium and lead as standard samples. Then, about 3 mg of PTFE powder was placed in an aluminum pan (crimped container), and the temperature was raised at a rate of 10 °C / min in the temperature range of 250 °C to 380 °C under an air flow of 200 ml / min for differential scanning calorimetry. The minimum point of the heat of fusion in the above region was taken as the melting point.

[0276] <Melt viscosity of PTFE>

[0277] According to ASTM D 1238, using a flow tester (manufactured by Shimadzu Corporation) and a -8L mold, 2 g of the sample preheated at 380 °C for 5 minutes was held at the above temperature with a load of 0.7 MPa for measurement.

[0278] <Average value of the particle size, circularity, and product of “(particle size)×(circularity)” of silicon dioxide>

[0279] The SEM photographs of silicon dioxide were taken using a scanning electron microscope SU8020 (manufactured by Hitachi High-Technologies Corporation), and the images were processed and analyzed using general-purpose image analysis software WinROOF (manufactured by Mitani Shoji Co., Ltd.).

[0280] <Average primary particle size of carbon black>

[0281] The average primary particle size of carbon black is an arithmetic average particle size, and is determined by observing carbon black with an electron microscope.

[0282] <Nitrogen Adsorption Specific Surface Area of ​​Carbon Black>

[0283] The molecular weight was determined by a nitrogen adsorption method using the S-BET formula in accordance with JIS K 6217-2.

[0284] <Adhesion Strength of Laminate>

[0285] The obtained laminate was cut into strips of 10 mm wide × 40 mm long × 3 parts, and a sample piece with a gripping edge formed by peeling off the fluororesin sheet was prepared. For this test piece, in order to measure the bonding strength of only the bonding surface, excluding the bonding strength of the boundary surface between the rubber layer and the fluororesin layer, the interface between the rubber layer and the fluororesin layer was slowly pulled apart by hand once to increase the gripping edge of 2 mm to 3 mm, and then a peeling test was performed at 25°C and a tensile speed of 50 mm / min using an Autograph (AGS-J5kN manufactured by Shimadzu Corporation) according to the method described in JIS-K-6256 (Adhesion test method for vulcanized rubber), and the bonding strength was measured, and the average value of the obtained N=3 data was calculated.

[0286] <Resistance value of rubber layer>

[0287] A rubber sheet with a thickness of about 2 mm (before crosslinking) was cut and pressed at 170° C. for 30 minutes to prepare a 4 cm×7 cm sample sheet. The surface resistance value of the sample sheet was measured when a voltage of 500 V was applied by contacting the probe tip with both ends of the sample sheet using an analog insulation resistance meter 24060 (manufactured by Yokogawa Instruments).

[0288] Examples 1 to 12 and Comparative Examples 1 to 6

[0289] (Production of fluororesin sheets)

[0290] A CTFE / TFE / PPVE copolymer having the following physical properties was pressed at 280° C. for 10 minutes to prepare a fluororesin sheet (thickness 0.12 mm).

[0291] CTFE / TFE / PPVE=21.3 / 76.3 / 2.4 (mol%)

[0292] MFR = 29.2 g / 10 min

[0293] Fuel permeability coefficient = 0.4g·mm / m 2 / sky

[0294] (Production of rubber composition (rubber sheet))

[0295] The details of the materials used in the preparation of the rubber composition are as follows.

[0296] Fluororubber: DAI-EL G902, manufactured by Daikin Industries

[0297] PTFE powder: TF9205, manufactured by 3M (PTFE micropowder, average particle size 7.7 μm, specific surface area 1.6 m 2 / g, melting point 327°C, melt viscosity 139Pa·s)

[0298] Silica: Sidistar (registered trademark) R300, manufactured by Elkem (average particle size 83.4 nm, average circularity 0.88, average value of the product of "(particle size) x (circularity)" 74.4 nm)

[0299] Cross-linking aid: Triallyl isocyanurate (TAIC), manufactured by Nippon Chemical Co., Ltd.

[0300] Crosslinking agent: Peroxide crosslinking agent, PERHEXA25B, manufactured by NOF Corporation

[0301] Basic multifunctional compound: N,N'-dicinnamylene-1,6-hexanediamine (V-3), carbon black manufactured by Daikin Industries, Ltd.: see Table 1 for details.

[0302] [Table 1]

[0303] Table 1

[0304]

[0305] The materials shown in Table 2 were kneaded using an 8-inch open roll mill to obtain a rubber composition (rubber sheet) in the form of a sheet having a thickness of about 2 mm.

[0306] In addition, for the rubber composition, the maximum torque value (MH) and the minimum torque value (ML) were measured at 170°C using MDR (model: MDR2000, manufactured by Alpha Technologies), and the induction time (T10) and the positive vulcanization time (T90) were obtained. The measurement results are shown in Table 2. T10 is the time to reach {(MH)-(ML)}×0.1+ML, T90 is the time to reach {(MH)-(ML)}×0.9+ML, and MH and ML are values ​​measured in accordance with JIS K 6300-2.

[0307] (Manufacturing of Laminated Body)

[0308] A rubber sheet having a thickness of about 2 mm and a fluororesin sheet having a thickness of about 0.12 mm were overlapped, a fluororesin film having a width of about 50 mm (thickness 10 μm) was sandwiched between the two sheets at one end, and then pressed at 170° C. for 30 minutes to obtain a sheet-shaped laminate. The results are shown in Table 2.

[0309]

Claims

1. A laminate comprising a rubber layer (A) and a fluororesin layer (B) laminated on the rubber layer (A), wherein: The rubber layer (A) is a conductive layer, and is formed of a rubber composition containing rubber and carbon black, wherein the content of the carbon black in the rubber composition is 1.0 to 100 parts by mass relative to 100 parts by mass of the rubber, and the nitrogen adsorption specific surface area of ​​the carbon black is 140 m 2 / g or less, The fluororesin layer (B) is formed of a melt-moldable fluororesin.

2. The laminate according to claim 1, wherein The average primary particle size of the carbon black is 28 nm or more.

3. The laminate according to claim 1 or 2, wherein: The content of the carbon black exceeds 8.0 parts by mass based on 100 parts by mass of the rubber.

4. The laminate according to any one of claims 1 to 3, wherein The rubber is fluororubber.

5. The laminate according to any one of claims 1 to 4, wherein The fuel permeability coefficient of the fluororesin is 2.0 g·mm / m 2 / day or less.

6. The laminate according to any one of claims 1 to 5, wherein The fluororesin is at least one selected from the group consisting of chlorotrifluoroethylene copolymers and tetrafluoroethylene / hexafluoropropylene / vinylidene fluoride copolymers.

7. The laminate according to any one of claims 1 to 6, wherein The rubber composition further contains a basic polyfunctional compound, and the content of the polyfunctional compound in the rubber composition is 0.1 parts by mass to 10 parts by mass based on 100 parts by mass of the rubber.

8. The laminate according to any one of claims 1 to 7, wherein The rubber composition also contains a peroxide crosslinking agent.

9. The laminate according to any one of claims 1 to 8, wherein The rubber composition further contains polytetrafluoroethylene, wherein the specific surface area of ​​the polytetrafluoroethylene is less than 8 m 2 / g, the average particle size of the polytetrafluoroethylene is 0.01 μm to 1000 μm, and the melt viscosity of the polytetrafluoroethylene at 380°C is 1×10 1 Pa·s~7×10 5 Pa·s.

10. The laminate according to any one of claims 1 to 9, wherein The rubber composition further contains silica, and the average value of the product of "(particle diameter)×(roundness)" of the silica is 17.5 nm or more and 500 μm or less.

11. The laminate according to any one of claims 1 to 10, wherein The rubber layer (A) and the fluororesin layer (B) are cross-linked and bonded.

12. The laminate according to any one of claims 1 to 11, wherein The bonding strength between the rubber layer (A) and the fluororesin layer (B) is 5 N / cm or more. 13 . The laminate according to claim 1 , which is a tube or a hose.

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