layered body

Abstract

The present application provides a laminate, which is a laminate provided with a rubber layer (A) and a fluororesin layer (B) laminated on the rubber layer (A), wherein the rubber layer (A) is a layer having electrical conductivity, 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 per 100 parts by mass of the rubber, the nitrogen adsorption specific surface area of the carbon black is 140 m 2 / g or less, and the fluororesin layer (B) is formed from a fluororesin capable of melt molding.

Description

Technical Field

[0001] This invention relates to laminates. Background Technology

[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 crosslinking fluororubber composition. This crosslinking fluororubber composition contains uncrosslinked fluororubber, silica particles, and a basic polyfunctional compound. The average value of the product of the silica particles (particle size × roundness) is 17.5 nm to 500 μm. The silica particles are contained in the crosslinking fluororubber composition in an amount of 1 part by mass to 70 parts by mass relative to 100 parts by mass of the uncrosslinked fluororubber.

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

[0005] Existing technical documents

[0006] Patent documents

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

[0008] The problem that the invention aims to solve

[0009] The purpose of this invention is to provide a laminate comprising a rubber layer and a fluororesin layer, wherein the rubber layer is conductive and the rubber layer and the fluororesin layer are firmly bonded together.

[0010] Methods for solving problems

[0011] According to the present invention, a laminate is provided, which comprises a rubber layer (A) and a fluoropolymer layer (B) laminated on the rubber layer (A), wherein the rubber layer (A) is a conductive layer formed of a rubber composition containing rubber and carbon black, wherein the content of carbon black in the rubber composition is 1.0 part by mass 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 m². 2 / g or less, the fluoropolymer layer (B) is formed of fluoropolymer that can be melt-formed.

[0012] The effects of the invention

[0013] According to the present invention, a laminate comprising a rubber layer and a fluoropolymer layer can be provided, wherein the rubber layer is conductive and the rubber layer and the fluoropolymer layer are firmly bonded together. Detailed Implementation

[0014] The specific embodiments of the present invention will be described in detail below, 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 fluoropolymer layer (B). Patent Document 1 describes a laminate comprising a fluororubber layer (A) and a fluoropolymer layer (B). However, there is a need for a technique that can impart conductivity to the rubber layer of the laminate and that can firmly bond the conductive rubber layer to the fluoropolymer layer.

[0016] In-depth research was conducted on the methods for solving the above problems. It was found that by selecting carbon black with a nitrogen adsorption specific surface area within a very limited range and mixing it into rubber in an appropriate amount, the rubber layer can be made conductive, and a laminate in which the conductive rubber layer and the fluororesin layer are firmly bonded can be obtained.

[0017] Next, the constituent elements used to construct such a previously unseen laminate will be described in detail.

[0018] (A) Rubber layer

[0019] The rubber layer in the laminate of the present invention is conductive. The presence or absence of conductivity in the rubber layer can be confirmed, for example, by measuring the surface resistivity of the rubber layer. From the viewpoint of sufficiently preventing the laminate from becoming charged, the surface resistivity of the rubber layer is preferably 10 MΩ or less, more preferably 5 MΩ or less, and even more preferably 1 MΩ or less.

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

[0021] A rubber layer is a layer formed from a rubber composition. A rubber layer is typically obtained by molding the rubber composition to obtain an uncrosslinked rubber layer, followed by 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 m². 2 Carbon black with a density of less than 1 g. By using carbon black with a large nitrogen adsorption specific surface area, a laminate in which a conductive rubber layer and a fluororesin layer are firmly bonded can be obtained.

[0025] The nitrogen adsorption specific surface area of ​​carbon black is 140 m². 2 / g or less, preferably 120m 2 / g or less, more preferably 100m 2 / g or less, more preferably 80m 2 / g or less, preferably 75m 2 / g or less, preferably 70m 2 / g or less, preferably 25m 2 / g or more.

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

[0027] The average primary particle size of the carbon black is preferably 28 nm or more, more preferably 32 nm or more, even more preferably 35 nm or more, preferably 200 nm or less, and even more preferably 100 nm or less. By using carbon black with an average primary particle size within the above-mentioned 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 mean particle size of the primary particles of carbon black. The average primary particle size of carbon black can be determined by observing the primary particles of carbon black using an electron microscope.

[0029] The content of carbon black in the rubber composition is 1.0 to 100 parts by weight relative to 100 parts by weight of rubber, preferably 3.0 parts by weight or more, more preferably 6.0 parts by weight or more, even more preferably more than 8.0 parts by weight, particularly preferably 9.0 parts by weight or more, preferably 50 parts by weight or less, more preferably 30 parts by weight or less, and even more preferably 20 parts by weight or less. By setting the content of carbon black with 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 softness and physical properties of the rubber layer can be appropriately adjusted.

[0030] As the carbon black contained in the rubber composition, conductive carbon black is used. By selecting conductive carbon black, and further selecting carbon black with a nitrogen adsorption specific surface area within a very limited range, and mixing it into the rubber in an appropriate amount, it is possible to impart conductivity to the rubber layer and obtain a laminate in which a conductive rubber layer and a fluoropolymer layer are firmly bonded. Quantitatively evaluating the conductivity of carbon black itself is not easy, but in the laminate of the present invention, when carbon black is mixed into the rubber composition in a manner that is within the above-mentioned range, a carbon black with conductivity sufficient to impart conductivity to the rubber layer is selected. In one embodiment, the type and content of carbon black are selected such that the surface resistivity of the rubber layer is within the above-mentioned range.

[0031] (rubber)

[0032] Examples of rubbers included in rubber compositions include: acrylonitrile-butadiene rubber (NBR) or its hydride (HNBR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), butadiene rubber (BR), natural rubber (NR), isoprene rubber (IR), and other diene-based rubbers; ethylene-propylene-terpolymer copolymer rubber; silicone rubber; butyl rubber; epichlorohydrin rubber; acrylic rubber; chlorinated polyethylene (CPE); a polymeric mixture of acrylonitrile-butadiene rubber and vinyl chloride (PVC-NBR); ethylene propylene diene rubber (EPDM); chlorosulfonated polyethylene (CSM); and fluororubber.

[0033] As a type of rubber, fluororubber is preferred. Fluororubber is typically composed of an amorphous polymer having fluorine atoms bonded to the carbon atoms constituting the main chain and exhibiting rubber-like elasticity. The aforementioned fluororubber can be composed of one polymer or two or more polymers. Fluororubber generally does not have a definite melting point.

[0034] 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 copolymer. 1 =CX 2 Rf 1 (where X) 1 and X 2 One is H, the other is F, Rf 1It is at least one of the group consisting of straight-chain or branched fluoroalkyl copolymers having 1 to 12 carbon atoms. Fluororubber is preferably a non-perfluorinated rubber, and more preferably a copolymer containing polymeric units (VdF units) from vinylidene fluoride.

[0035] As a copolymer containing VdF units, a copolymer comprising VdF units and copolymer units from fluorinated olefinic monomers (wherein excluding VdF units, also referred to hereinafter as "fluorinated olefinic monomer units (a)") is preferred. The copolymer containing VdF units can be a copolymer consisting solely of VdF units and fluorinated olefinic monomer units (a), or a copolymer further comprising copolymer units from monomers capable of copolymerizing with VdF and fluorinated olefinic monomers (wherein excluding VdF, also referred to hereinafter as "fluorinated olefinic monomers (a)").

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

[0037] The amount of copolymer units (excluding VdF units) from monomers capable of copolymerizing with VdF and fluorinated olefinic monomer units (a) is preferably 0 to 10 mol relative to the total amount of VdF units and copolymer units from fluorinated olefinic monomer units (a).

[0038] Examples of fluorinated olefinic monomers (a) include TFE, CTFE, trifluoroethylene, HFP, trifluoropropylene, tetrafluoropropylene, pentafluoropropylene, trifluorobutene, tetrafluoroisobutylene, PAVE, fluoroethylene, and general formula (1):

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

[0040] (where X) 1 and X 2 One is H, the other is F, Rf 1 Compounds of the general formula (2) are straight-chain or branched fluoroalkyl groups having 1 to 12 carbon atoms.

[0041] CFX = CXOCF2OR 1 (2)

[0042] (In the formula, X being the same or different represents H, F, or CF3, R) 1 The term refers to a straight-chain or branched fluoroalkyl group having 1 to 6 carbon atoms and containing at least one to two atoms selected from the group consisting of H, Cl, Br, and I, or a cyclic fluoroalkyl group having 5 or 6 carbon atoms and containing at least one to two atoms selected from the group consisting of H, Cl, Br, and I. Fluorinated monomers such as fluorovinyl ethers as shown in formula (2) are preferred. Among these, at least one selected from the group consisting of CH2=CFCF3, fluorovinyl ethers shown in formula (2), TFE, HFP, and PAVE is more preferred.

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

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

[0045] (where Y) 1 F or CF3, Rf represents a perfluoroalkyl group with 1 to 5 carbon atoms. p represents an integer from 0 to 5, q represents an integer from 0 to 5. (The compound is shown in the image.)

[0046] As PAVE, perfluoro(methyl vinyl ether) or perfluoro(propyl vinyl ether) is more preferred, and perfluoro(methyl vinyl ether) is even more preferred. They can be used individually or in any combination.

[0047] Examples of monomers that can copolymerize with VdF and fluorinated olefinic monomers (a) include ethylene, propylene, and alkyl vinyl ethers.

[0048] Specifically, the copolymer containing VdF units is preferably selected from at least one copolymer chosen 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. Among these copolymers containing VdF units, from the perspective of heat resistance, at least one copolymer chosen from the group consisting of VdF / HFP copolymers and VdF / HFP / TFE copolymers is particularly preferred. These copolymers containing VdF units preferably satisfy the above-described compositional ratio of VdF units to fluorinated olefinic monomer units (a).

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

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

[0051] As a VdF / PAVE copolymer, the preferred molar ratio of VdF / PAVE is 65–90 / 10–35.

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

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

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

[0055] The aforementioned fluororubber is preferably composed of copolymers comprising copolymer units from monomers providing crosslinking sites. Examples of monomers providing crosslinking sites include, for instance, iodine-containing monomers such as perfluorinated (6,6-dihydro-6-iodo-3-oxo-1-hexene) or perfluorinated (5-iodo-3-oxo-1-pentene) as described in Japanese Patent Application Publication Nos. 5-63482 and 7-316234; bromine-containing monomers as described in Japanese Patent Application Publication No. 4-505341; and cyano-containing monomers, carboxyl-containing monomers, and alkoxycarbonyl-containing monomers as described in Japanese Patent Application Publication Nos. 4-505345 and 5-500070.

[0056] Fluororubber is preferably a fluororubber having iodine or bromine atoms at the ends of its main chain. Fluororubber having iodine or bromine atoms at the ends of its main chain can be manufactured by emulsion polymerization of monomers in an aqueous medium with the addition of a free radical initiator in a substantially anaerobic state and in the presence of a halogen compound. Representative examples of the halogen compounds used include, for example, those with the general formula:

[0057] R 2 I x Br y

[0058] (In the formula, x and y are integers from 0 to 2 and satisfy 1≤x+y≤2, R) 2 It is a compound consisting of 1 to 16 saturated or unsaturated fluorocarbon groups, 1 to 16 saturated or unsaturated chlorofluorocarbon groups, 1 to 3 hydrocarbon groups, or 3 to 10 cyclic hydrocarbon groups that can be replaced by iodine or bromine atoms (which may contain oxygen atoms).

[0059] Examples of halogen compounds include, for instance, 1,3-diiodoperfluoropropane, 1,3-diiodo-2-chloroperfluoropropane, 1,4-diiodoperfluorobutane, 1,5-diiodo-2,4-dichloroperfluoropentane, 1,6-diiodoperfluorohexane, 1,8-diiodoperfluorooctane, 1,12-diiodoperfluorododecane, 1,16-diiodoperfluorohexadecane, diiodomethane, 1,2-diiodoethane, 1,3-diiodo-n-propane, CF₂Br₂, BrCF₂CF₂Br, CF₃CFBrCF₂Br, CFClBr₂, and 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, monoiodomonobromo-substituted derivatives of benzene, diiodomonobromo-substituted derivatives of benzene, and (2-iodoethyl) and (2-bromoethyl)-substituted derivatives of benzene, etc. These compounds can be used alone or in combination.

[0060] Among these, 1,4-diiodoperfluorobutane or diiodomethane are preferred in terms of polymerization reactivity, crosslinking reactivity, and ease of acquisition.

[0061] From the perspective of good processability during the manufacture of rubber compositions, the Mooney viscosity (ML) of the aforementioned fluororubber is... 1+10 (100℃) Preferably 5 to 200, more preferably 10 to 150, and even more preferably 20 to 100.

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

[0063] Measurement equipment: MV2000E model manufactured by ALPHATECHNOLOGIES

[0064] Rotor speed: 2 rpm

[0065] Measurement temperature: 100℃

[0066] The rubber composition preferably consists of only the above-mentioned fluororubber as its rubber component.

[0067] (Basic polyfunctional compound)

[0068] The rubber composition preferably also contains a basic polyfunctional compound. The presence of a basic polyfunctional compound in the rubber composition enables a stronger bond between the rubber layer and the fluoropolymer layer. A basic polyfunctional compound is a compound exhibiting basicity, possessing two or more functional groups with identical or different structures within a single molecule.

[0069] The functional groups present in a basic multifunctional compound are preferably those exhibiting basicity, and are preferably selected, for example, from -NH2 or -NH3. + -NHCOOH, -NHCOO - -N=CR 1 R 2 (where R is in the formula) 1 and R 2 (independently an organic group having 0 to 12 carbon atoms), -NR 3 R 4 (where R is in the formula) 3 and R 4 (independently an organic group having 0 to 12 carbon atoms), -NR 3 R 4 R 5 (where R is in the formula) 3 R 4 and R 5 At least one of the following groups: an organic group having 0 to 12 carbon atoms independently, and a functional group that has been transformed into the above-mentioned functional group by heating; more preferably, a functional group selected from -NH2 or -NH3. + -N=CR 1 R 2 (where R is in the formula) 1 and R 2 Same as above) and -NR 3 R 4 R 5 (where R is in the formula) 3 R 4 and R 5At least one of the group consisting of (as described above), more preferably selected from -NH2 and -NH3. + and -N=CR 1 R 2 (where R is in the formula) 1 and R 2 At least one of the groups consisting of the same as described above. The number of functional groups in 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 The group is preferably an organic group with -H or 1 to 12 carbon atoms, and more preferably a hydrocarbon group with -H or 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] The above-mentioned R is preferred 1 -H or -CH3, R 2 -CH=CHR 6 (R 6 It is phenyl (-C6H5), benzyl (-CH2-C6H5) or -H), more preferably the above-mentioned R. 1 -H, R 2 It is -CH=CH-C6H5.

[0072] Examples of such basic polyfunctional compounds include ethylenediamine, propylenediamine, putrescine, cadaverine, 1,6-hexanediamine, heptanediamine, octanediamine, nonanediamine, decanedanediamine, undecanediamine, dodecanediamine, phenylenediamine, N,N'-dicinnamyl-1,6-hexanediamine, N,N,N',N'-tetramethyl-1,6-hexanediamine, N,N'-dimethyl-1,6-hexanediamine, and 6-aminohexyluric acid.

[0073] The aforementioned basic polyfunctional compounds preferably contain at least two nitrogen atoms in their molecules, with the interatomic distance between nitrogen atoms being [missing information]. The above. More preferably, the interatomic distance between nitrogen atoms is... The above, further preferred The above, especially preferred In summary, by increasing the interatomic distance between nitrogen atoms, the flexibility of basic multifunctional compounds increases, and cross-linking becomes easier.

[0074] Here, the interatomic distances between nitrogen atoms are calculated using the following method. That is, the structure optimization of each base is calculated using the density functional theory method (the program is Gaussian 03, the density functional is B3LYP, and the ground state function is 6-31G*).

[0075] As a basic multifunctional compound, from the perspective of adhesion between the rubber layer and the fluororesin layer, it is preferably selected from N,N'-dicinnamyl-1,6-hexanediamine and NH2-(CH2). n- At least one of the group consisting of NH2 (where n is 5 to 12), more preferably at least one of the group consisting of 1,6-hexanediamine and N,N'-dicinnamyl-1,6-hexanediamine.

[0076] In the rubber composition, from the viewpoint of more firmly bonding the rubber layer and the fluororesin layer, the content of the alkaline polyfunctional compound is preferably 0.1 to 10 parts by weight relative to 100 parts by weight of rubber, more preferably 1.0 parts by weight or more, even more preferably 2.0 parts by weight or more, more preferably 7.0 parts by weight or less, and even more preferably 5.0 parts by weight or less.

[0077] (Polytetrafluoroethylene)

[0078] From the perspective of enabling a stronger bond between the rubber layer and the fluoropolymer layer, the rubber composition preferably also contains polytetrafluoroethylene (PTFE).

[0079] From the perspective of enabling a stronger bond between the rubber layer and the fluoropolymer layer, the specific surface area of ​​PTFE is preferably less than 8 m². 2 / g, more preferably 6.0m 2 / g or less, more preferably 4.0m 2 / g or less, preferably 3.0m 2 / g or less, preferably 0.5m 2 / g or more, more preferably 1.0m 2 / g or more.

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

[0081] PTFE preferably has melt processability. Furthermore, the melt viscosity of PTFE at 380°C is preferably 1 × 10⁻⁶. 1 Pa·s ~ 7 × 10 5 Pa·s.

[0082] PTFE with melt viscosity within the aforementioned range is low molecular weight, for example, PTFE with a number average molecular weight of 600,000 or less. "High molecular weight PTFE" with a number average molecular weight exceeding 600,000 exhibits the fibrillation characteristics characteristic of PTFE (see, for example, Japanese Patent Application Publication No. 10-147617). High molecular weight PTFE has high melt viscosity and is non-melt processable. The PTFE contained in the rubber layer preferably does not exhibit fibrillation characteristics sufficient for paste extrusion molding. The melt viscosity and number average molecular weight of PTFE can be adjusted by modifying the polymerization conditions of TFE during PTFE manufacturing or by irradiating PTFE with electron beams.

[0083] The melt viscosity is as follows: according to ASTM D 1238, using a flow tester (manufactured by Shimadzu Corporation) and Using an -8L mold, a 2g sample preheated to 380°C for 5 minutes was held at the aforementioned temperature under a load of 0.7MPa for measurement. The resulting value was the melt viscosity. The number-average molecular weight was calculated from the melt viscosity measured using the above method.

[0084] The apparent density of PTFE is preferably 0.15 g / cm³. 3 ~0.80g / cm 3 More preferably, it is 0.25 g / cm³. 3 The above, more preferably 0.55 g / cm³ 3 the following.

[0085] Apparent density can be determined according to JIS K 6891.

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

[0087] Regarding the average particle size, a laser diffraction particle size distribution measuring device (e.g., manufactured by Japan Laser Co., Ltd.) was used without cascading. 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.

[0088] The preferred melting point for PTFE is 324℃~333℃.

[0089] Regarding the melting point of PTFE, a differential scanning calorimeter RDC220 (DSC) manufactured by SII Nanotechnology was used. Indium and lead were used as standard samples for temperature calibration beforehand. Then, about 3 mg of PTFE powder was placed in an aluminum pan (capped container), and the temperature was increased at 10 °C / min in the temperature range of 250 °C to 380 °C under an air flow of 200 ml / min. The melting point was determined by differential scanning calorimetry, and the minimum point of heat of fusion in the above 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] Regarding MFR, the weight (g) of polymer flowing out of a nozzle with a diameter of 2 mm and a length of 8 mm per unit time (10 minutes) under a load of 1.2 kg at 372 °C is measured using a melt flow index tester (e.g., manufactured by Toyo Seiki Co., Ltd.), which can be used to specify the specific MFR.

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

[0093] Regarding the loss on ignition, the PTFE (sample) is heated at 300°C for 2 hours, the mass of the sample after heating is measured, and the ratio of the loss of the sample after heating to the mass of the sample before heating is calculated, which can be used to determine the loss.

[0094] PTFE can be a homopolymer of TFE or a modified PTFE containing TFE units and modified monomer units that can copolymerize with TFE.

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

[0096] In this invention, a modified monomer unit refers to a portion of the molecular structure of modified PTFE, specifically a portion derived from the modified monomer. All monomer units refer to portions derived from all monomers within the molecular structure of modified PTFE. The content of the aforementioned modified monomer units is determined by infrared spectroscopy or NMR (nuclear magnetic resonance).

[0097] As a modifying monomer in modified PTFE, there are no particular limitations as long as it can copolymerize with TFE. Examples include perfluoroolefins such as hexafluoropropylene [HFP]; chlorofluoroolefins such as trifluorochloroethylene [CTFE]; hydrofluoroolefins such as trifluoroethylene and vinylidene fluoride [VDF]; perfluorovinyl ethers; and perfluoroalkyl ethylene. In addition, one or more modifying monomers can be used.

[0098] As for the aforementioned perfluorovinyl ethers, there are no particular limitations; examples such as general formula (I) can be cited:

[0099] CF2 = CF - ORf(I)

[0100] (where Rf represents a perfluorinated organic group) and other perfluorinated unsaturated compounds. In this specification, the term "perfluorinated organic group" refers to an organic group in which all hydrogen atoms bonded to carbon atoms are replaced by fluorine atoms. The aforementioned perfluorinated organic group may have ether oxygen.

[0101] Examples of perfluorovinyl ethers include, for instance, perfluoro(alkylvinyl ethers) [PAVE] in which Rf represents a perfluoroalkyl group having 1 to 10 carbon atoms. The preferred number of carbon atoms in the perfluoroalkyl group is 1 to 5.

[0102] Examples of perfluoroalkyl groups in the above-mentioned PAVE include perfluoromethyl, perfluoroethyl, perfluoropropyl, perfluorobutyl, perfluoropentyl, and perfluorohexyl, with perfluoropropyl vinyl ether [PPVE] being the most preferred as the perfluoroalkyl group.

[0103] Further examples of the aforementioned perfluorovinyl ethers include:

[0104] In general formula (I), Rf is a perfluorinated (alkoxyalkyl) substance with 4 to 9 carbon atoms, and Rf is the following formula:

[0105] [Chemistry 1]

[0106]

[0107] (where m represents 0 or an integer from 1 to 4) The substance with the group shown, Rf, is as follows:

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

[0109] Substances containing groups such as (where n represents an integer from 1 to 4).

[0110] There are no particular limitations on perfluoroalkyl ethylene; examples include perfluorobutylethylene (PFBE), perfluorohexylethylene, and perfluorooctylethylene.

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

[0112] PTFE is preferably modified PTFE, more preferably modified PTFE comprising TFE units and polymer units (HFP units) from HFP.

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

[0114] (Silicon dioxide)

[0115] From the perspective of enabling a stronger bond between the rubber layer and the fluoropolymer layer, the rubber composition preferably also contains silica.

[0116] As the silica, both alkaline silica and acidic silica can be used. From an adhesive perspective, alkaline silica is preferred. Examples of alkaline silica include Carplex 1120 (manufactured by DSL Japan), Sidistar R300 (manufactured by Elkem), Silene 732D (manufactured by PPG Industries), and Inhibisil 75 (manufactured by PPG Industries). Furthermore, from the perspective of providing a stronger bond between the rubber layer and the fluoropolymer layer, silica with a large average particle size is preferred. Examples of silica with a large average particle size include Sidistar R300 (manufactured by Elkem), Sidistar T120U (manufactured by Elkem), the Admafine series (manufactured by Admatechs), and the EXCELICA series (manufactured by Tokuyama).

[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, most preferably 70.0 nm or more, 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, most preferably 80.0 nm or more, preferably 500 μm or less, more preferably 300 μm or less, and further preferably 100 μm or less.

[0119] The average roundness of the silica is preferably 0.80 or higher, more preferably 0.85 or higher. The theoretical upper limit for roundness 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 then analyzing the scanning electron microscope (SEM) images of the silica particles in the coated film. In the image analysis, the SEM images are processed to remove noise and binarize them. One hundred particles are randomly selected from the processed images, and the average diameter of the silica particles observed in a two-dimensional image with a depth of field of 1 μm to 2 μm is measured. Here, for a circular two-dimensional shape, "diameter" corresponds to the diameter (not the radius). For a non-circular two-dimensional shape with an area S, "diameter" is considered equivalent to the diameter of a circle, obtained by taking the square root of (4 × S / π).

[0121] The "average roundness" of silica can be determined by adsorbing silica particles onto a PET film, coating the film using platinum sputtering, and then analyzing SEM images of the silica particles in the coated film. In the image analysis, the SEM images are processed to remove noise and binarize them. Then, 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 the two-dimensional shape is defined as follows.

[0122] (Roundness) = 4π × (Area of ​​the binarized two-dimensional cross-sectional image of the silicon dioxide particles) / (Outer perimeter of the binarized two-dimensional cross-sectional image of the silicon dioxide particles) 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) and (roundness) of silica can be determined by adsorbing silica particles onto a PET film, coating the film using platinum sputtering, and then analyzing SEM images of the silica particles in the coated film. In the image analysis, the SEM images are processed to remove noise and binarize them. Then, 100 particles are randomly selected from the processed image, and the average value of the product of (particle size) and (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 determination of the average particle size, average roundness and the average of the product of "(particle size) × (roundness)", sometimes aggregated particles are incorrectly counted as one large particle, and gray shadows in the particle image are not identified as part of the particle. Therefore, only well-defined silica particles are selected as representative samples, and duplicate silica particles are ignored.

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

[0127] (Cross-linking agent)

[0128] From the perspective of enabling a stronger bond between the rubber layer and the fluororesin layer, the rubber composition preferably also contains a crosslinking agent. As the crosslinking agent, a peroxide crosslinking agent, etc., can be selected depending on the purpose. The rubber composition preferably also contains a peroxide crosslinking agent.

[0129] There are no particular limitations on the peroxide crosslinking agent, and examples include organic peroxides. Among organic peroxides, substances that readily generate peroxide free radicals in the presence of heat or a redox system are preferred. Examples include 1,1-bis(tert-butylperoxy)-3,5,5-trimethylcyclohexane, 2,5-dimethylhexane-2,5-dihydroxyperoxide, di-tert-butylperoxide, tert-butylcumylperoxide, dicumylperoxide, 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-butylperoxybenzene, 2,5-dimethyl-2,5-di(benzoyl peroxide)hexane, tert-butyl maleate peroxide, and tert-butyl isopropyl carbonate peroxide. Dialkyl compounds are more preferred.

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

[0131] (Cross-linking aid)

[0132] When the crosslinking agent is a peroxide crosslinking agent, the rubber composition preferably includes a crosslinking aid. Examples of crosslinking aids include, for instance, triallyl cyanurate, trimethylallyl isocyanurate, triallyl isocyanurate (TAIC), 1,3,5-triacryloylhexahydro-1,3,5-triazine, triallyl trimellitate, N,N'-m-phenylene bismaleimide, diacetylacetate, diallyl phthalate, tetraallyl terephthalamide, triallyl phosphate, bismaleimide, and fluorinated triallyl isocyanurate (1,3,5-tris(2,3,3-trifluoro-2-propane)). Examples of suitable crosslinking agents include (alkenyl)-1,3,5-triazine-2,4,6-trione, tris(diallylamine)-triazine, triallyl phosphite, N,N-diallylacrylamide, 1,6-divinyldodecylfluorohexane, hexamethylenephosphoramide, N,N,N',N'-tetraallylphthalamide, N,N,N',N'-tetraallylmalondiamide, trivinylisocyanurate, 2,4,6-trivinylmethyltrisiloxane, tris(5-norbornene-2-methylene)cyanurate, and triallyl phosphite. Among these, triallyl isocyanurate (TAIC) is preferred due to its superior crosslinking properties and the 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 weight relative to 100 parts by weight of rubber, more preferably 1.0 parts by weight or more, more preferably 7 parts by weight or less, and even more preferably 5 parts by weight or less.

[0134] (Other components of the 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 fluoropolymer layer.

[0136] Examples of 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 Group (II) metals in the periodic table, oxides, basic carbonates, basic carboxylates, basic phosphites, and basic sulfites of Group (IV) metals in 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 (hydrated lime), calcium carbonate, calcium silicate, calcium stearate, zinc stearate, calcium phthalate, calcium phosphite, tin oxide, and basic tin phosphite.

[0138] When using a peroxide crosslinking agent as a crosslinking agent, the content of metal oxides, metal hydroxides, weak acid salts of alkali metals, and weak acid salts of alkaline earth metals is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, relative to 100 parts by mass of rubber. From the perspective of acid resistance, it is even more preferable that these substances are not present.

[0139] In rubber compositions, additives commonly used in rubber compositions may be blended as needed, such as fillers, processing aids, plasticizers, colorants, stabilizers, adhesive aids, acid acceptors, anti-sticking agents, conductivity imparting agents, thermal conductivity imparting agents, surface non-adhesives, softening agents, heat resistance improvers, flame retardants, and other additives. It may also contain one or more conventional crosslinking agents or crosslinking accelerators that are different from the above.

[0140] (B) Fluoropolymer layer

[0141] The fluoropolymer layer is a layer formed from fluoropolymer. In this invention, fluoropolymer refers to a partially crystalline fluoropolymer, which is a fluoroplastic. Fluoropolymer has a melting point and is thermoplastic.

[0142] The fluoropolymer layer forming the laminate of the present invention is a melt-molded fluoropolymer. "Mel-molded" means that the polymer can be melted and processed using conventional processing equipment such as extruders and injection molding machines. Therefore, melt-molded fluoropolymers typically have a melt flow rate of 0.01 g / 10 min to 500 g / 10 min as measured by the method described later.

[0143] As a fluoropolymer, a fluoropolymer with a low fuel permeability coefficient is preferred. The fuel permeability coefficient of the fluoropolymer is preferably 2.0 g·mm / m. 2 less than / day, more preferably 1.5g·mm / m 2 Less than / day, further preferably 0.8g·mm / m 2 Less than / day, preferably 0.55g·mm / m 2 Less than / day, optimally 0.5g·mm / m 2 / day or less. By containing a fluoropolymer with a fuel permeability coefficient within the above range in the fluoropolymer layer, the fluoropolymer layer exhibits excellent low fuel permeability, and the laminate can be appropriately used as a fuel hose, etc.

[0144] The fuel permeability coefficient is calculated as follows: When 18 mL of an isooctane / toluene / ethanol mixed solvent (45:45:10 volume ratio) is added, the permeability coefficient is calculated as follows: A fluoropolymer sheet (45 mm in diameter and 120 μm thick) made from the resin to be tested is added to a SUS316 fuel transmission coefficient measuring cup with a height of 20 mm. The value obtained is calculated based on the mass change measured at 60 °C.

[0145] (Method for manufacturing fluoropolymer sheets)

[0146] Resin granules were added into a mold with a diameter of 120 mm and placed in a press heated to 300 °C. The press was melted and pressed at a pressure of about 2.9 MPa to obtain a fluoropolymer sheet with a thickness of 0.12 mm. The sheet was then processed into a sheet with a diameter of 45 mm and a thickness of 120 μm.

[0147] As a fluoropolymer, from the viewpoint of obtaining a laminate with excellent fuel permeability, it is preferably selected from at least one of the group consisting of polychlorotrifluoroethylene (PCTFE), CTFE-based copolymers and TFE / HFP / VdF copolymers. From the viewpoint of obtaining a laminate with better adhesion between the rubber layer and the fluoropolymer layer and excellent fuel permeability, it is more preferably selected from at least one of the group consisting of CTFE-based copolymers and TFE / HFP / VdF copolymers. From the viewpoint of obtaining a laminate with better adhesion between the rubber layer and the fluoropolymer layer and excellent fuel permeability and flexibility, CTFE-based copolymers are even more preferred.

[0148] In the TFE / HFP / VdF copolymer, due to the excellent low fuel permeability resulting from a low VdF content, the copolymerization ratio (molar percentage) 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 (molar ratio), even more preferably 77–95 / 2–8 / 2–15.5 (molar ratio), and most preferably 79–90 / 5–8 / 5–15 (molar ratio). Additionally, the TFE / HFP / VdF copolymer may also contain 0–20 mol% of other monomers. Other monomers may include at least one monomer selected from the group consisting of perfluoro(methyl vinyl ether), perfluoro(ethyl vinyl ether), perfluoro(propyl vinyl ether), trifluorochloroethylene, 2-chloropentafluoropropylene, perfluorinated vinyl ethers (e.g., perfluoroalkoxy vinyl ethers such as CF3OCF2CF2CF2OCF=CF2), perfluoroalkyl vinyl ethers, perfluoro-1,3-butadiene, trifluoroethylene, hexafluoroisobutylene, fluoroethylene, ethylene, propylene, and alkyl vinyl ethers, with perfluoro(methyl vinyl ether), perfluoro(ethyl vinyl ether), and perfluoro(propyl vinyl ether) being preferred.

[0149] PCTFE is a homopolymer of trifluorochloroethylene.

[0150] As a CTFE-based copolymer, it preferably contains copolymer units (CTFE units) derived from CTFE and copolymers derived from TFE, HFP, PAVE, VdF, vinyl fluoride, hexafluoroisobutylene, and other polymers with the formula: CH2=CX. 3 (CF2) n X 4 (where X) 3 For H or F, X 4 The copolymer unit is a copolymer of at least one monomer from the group consisting of H, F, or Cl (where n is an integer from 1 to 10), ethylene, propylene, 1-butene, 2-butene, vinyl chloride, and vinylidene chloride. Furthermore, CTFE-based copolymers are more preferably fully halogenated polymers.

[0151] As a CTFE-based copolymer, it is more preferable to include CTFE units and copolymer units from at least one monomer selected from the group consisting of TFE, HFP, and PAVE, and even more preferably, it is composed of substantially only these copolymer units. In addition, from the perspective of low fuel permeability, it is preferable not to include monomers with CH bonds such as ethylene, vinylidene fluoride, and vinyl fluoride.

[0152] Fully halogenated polymers that do not contain monomers with CH bonds are generally difficult to bond with rubber (especially fluororubber), but according to the configuration of the present invention, even when the fluororesin contains fully halogenated polymers, the interlayer bond between the rubber layer and the fluororesin layer is strong.

[0153] CTFE copolymers are preferably composed of 10 mol% to 90 mol% CTFE units having all monomer units.

[0154] As a CTFE-based copolymer, it is particularly preferred to include CTFE units, TFE units, and monomer (α) units from monomers (α) that can copolymerize with them.

[0155] The “CTFE unit” and “TFE unit” are, respectively, the portions from CTFE (-CFCl-CF2-) and the portions from TFE (-CF2-CF2-) in the molecular structure of the CTFE copolymer. Similarly, the “monomer (α) unit” is the portion formed by the addition of monomer (α) in the molecular structure of the CTFE copolymer.

[0156] As a monomer (α), there are no particular limitations as long as it is a monomer capable of copolymerizing with CTFE and TFE. Examples include ethylene (Et), vinylidene fluoride (VdF), and CF2=CF-ORf. 2 (where Rf) 2 PAVE and CX are perfluoroalkyl groups having 1 to 8 carbon atoms. 5 X 6 =CX 7 (CF2)n X 8 (where X) 5 X 6 and X 7 They may be the same or different, consisting of hydrogen or fluorine atoms; X 8 Vinyl monomers (where n is an integer from 1 to 10, consisting of hydrogen, fluorine, or chlorine atoms) are represented by CF2=CF-O-Rf. 3 (where Rf) 3 These are alkyl perfluorovinyl ether derivatives, etc., represented by perfluoroalkyl groups having 1 to 5 carbon atoms.

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

[0158] As a monomer (α), it is preferably selected from at least one of the group consisting of PAVE, the above-mentioned vinyl monomers and alkyl perfluorovinyl ether derivatives, more preferably from at least one of 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% and 80 mol% to 10 mol%. Furthermore, it is also preferable that the copolymer consists of 15 mol% to 25 mol% CTFE units and 85 mol% to 75 mol% TFE units.

[0160] In CTFE-based copolymers, the preferred total content of CTFE units and TFE units is 90 mol% to 99.9 mol%, and the monomer (α) units are 0.1 mol% to 10 mol%. When the monomer (α) units are less than 0.1 mol%, the moldability, resistance to environmental stress cracking, and resistance to fuel cracking tend to deteriorate; if they exceed 10 mol%, they tend to have poor fuel permeability, heat resistance, and mechanical properties.

[0161] From the perspectives of low fuel permeability and adhesion, the fluoropolymer is more preferably selected from at least one of the group consisting of PCTFE, CTFE / TFE / PAVE copolymer and TFE / HFP / VdF copolymer, more preferably selected from at least one of the group consisting of CTFE / TFE / PAVE copolymer and TFE / HFP / VdF copolymer, and particularly preferably selected from CTFE / TFE / PAVE copolymer.

[0162] In the CTFE / TFE / PAVE copolymer, the PAVE mentioned above can be a perfluoro(methyl vinyl ether) (PMVE), a perfluoro(ethyl vinyl ether) (PEVE), a perfluoro(propyl vinyl ether) (PPVE), a perfluoro(butyl vinyl ether), etc., and preferably at least one selected from the group consisting of PMVE, PEVE and PPVE.

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

[0164] The structural units such as CTFE units are constructed by performing... 19 The values ​​obtained from F-NMR analysis.

[0165] Fluoropolymers can be fluoropolymers in which at least one reactive functional group selected from the group consisting of carbonyl, hydroxyl, heterocyclic and amino groups is introduced into the main chain end and / or side chain of a polymer.

[0166] In this invention, "carbonyl" refers to a carbon-2 valence group composed of a carbon-oxygen double bond, represented by the group indicated by -C(=O)-. There are no particular limitations on reactive functional groups containing carbonyl groups, and examples include carbonate groups, carboxyl halogen groups (haloformyl groups), formyl groups, carboxyl groups, ester bonds (-C(=O)O-), acid 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-), and aminooxaloyl groups (NH2-C(=O)-C(=O)-), etc., which contain carbonyl groups as part of their chemical structure.

[0167] In amide groups, imide groups, carbamate bonds, carbamoyl groups, carbamoyloxy groups, urea groups, aminooxoyl groups, etc., the hydrogen atom bonded to its nitrogen atom can be replaced by a hydrocarbon group such as an alkyl group.

[0168] From the perspectives of ease of introduction, moderate heat resistance of fluororesins, and good adhesion at lower temperatures, the reactive functional groups are preferably amide groups, carbamoyl groups, hydroxyl groups, carboxyl groups, carbonate groups, carboxyl halogen groups, and acid anhydride bonds, and are further preferably amide groups, carbamoyl groups, hydroxyl groups, carbonate groups, carboxyl halogen groups, and acid anhydride bonds.

[0169] Fluoropolymers can be obtained through existing known polymerization methods such as suspension polymerization, solution polymerization, emulsion polymerization, and bulk polymerization. In the above polymerization processes, the temperature, pressure, and other conditions, as well as the polymerization initiator or other additives, can be appropriately set according to the composition and amount of the fluoropolymer.

[0170] The melting point of fluoropolymers is not particularly limited, but is preferably 160°C to 270°C. Regarding the melting point of fluoropolymers, a DSC apparatus (manufactured by SEIKO) is used to heat the resin at a rate of 10°C / minute, and the temperature corresponding to the maximum value in the heat of fusion curve during the heating process is determined and taken as the melting point of the fluoropolymer.

[0171] Furthermore, the molecular weight of the fluoropolymer is preferably within the range that allows the resulting laminate to exhibit good mechanical properties and low fuel permeability. For example, when melt flow rate (MFR) is used as an indicator of molecular weight, the MFR at any temperature within the typical molding temperature range of the fluoropolymer, approximately 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 even more preferably 2 g / 10 min to 35 g / 10 min. For example, when the fluoropolymer is a PCTFE, CTFE-based copolymer, or a TFE / HFP / VdF copolymer, the MFR is measured at 297°C.

[0172] Regarding MFR, the weight (g) of polymer flowing out of a nozzle with a diameter of 2 mm and a length of 8 mm is measured per unit time (10 minutes) under a load of 5 kg at 297 °C, and thus can be specified.

[0173] The fluoropolymer layer may contain one or more such fluoropolymers.

[0174] It should be noted that when fluoropolymers are fully halogenated polymers, they exhibit superior chemical resistance and low fuel permeability. Fully halogenated polymers are polymers in which halogen atoms are bonded to all carbon atoms in the main chain.

[0175] The fluoropolymer layer can be further blended with various fillers such as inorganic powders, glass fibers, carbon powders, carbon fibers, and metal oxides, within a range that does not impair its performance, depending on the purpose or application.

[0176] For example, to further reduce fuel permeability, layered clay minerals of the montmorillonite series such as montmorillonite, bedesite, saponite, chloromontmorillonite, lithium montmorillonite, zinc montmorillonite, and styrene-magnesium silicate, or micro-layered minerals with a high length-to-thickness ratio such as mica, can be added.

[0177] (laminated body)

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

[0179] The thickness of the fluoropolymer layer is not limited, but is preferably 10 μm or more. An upper limit for the thickness of the fluoropolymer 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, even more preferably 5 N / cm or more, and particularly preferably 6 N / cm or more.

[0181] The adhesive strength was measured as follows: The laminate was cut into strips 10 mm wide × 40 mm long × 3 pieces to make a test piece. For this test piece, in order to eliminate the influence of the adhesive strength at the interface between the rubber layer and the fluororesin layer, only the adhesive strength of the adhesive surface was measured. The interface between the rubber layer and the fluororesin layer was slowly pulled apart by hand once to increase the gripping edge by 2 mm to 3 mm. Then, a peel test was performed at 25°C and a tensile speed of 50 mm / min using an Autograph (Shimadzu Corporation AGS-J 5kN) according to the method described in JIS-K-6256 (Test Method for Adhesion of Vulcanized Rubber). The peel pattern was observed and measured, and the obtained value was the adhesive strength mentioned above.

[0182] In the laminate of the present invention, the rubber layer and the fluoropolymer layer are preferably directly bonded, and more preferably directly crosslinked bonded. Such a laminate is obtained by crosslinking a non-crosslinked rubber layer and a fluoropolymer layer after lamination. The laminate of the present invention can be a crosslinked laminate.

[0183] Crosslinking treatment can employ existing, known methods and conditions for crosslinking rubber compositions. Examples include: methods for long-term crosslinking of uncrosslinked laminates; and methods for subjecting uncrosslinked laminates to a short-term heat treatment as a pretreatment (which also results in crosslinking), followed by a long-term crosslinking process. Among these, the method of subjecting the uncrosslinked laminates to a short-term heat treatment as a pretreatment followed by a long-term crosslinking process is preferred because the adhesion between the rubber layer and the fluoropolymer layer is easily obtained through the pretreatment, and the rubber layer is already crosslinked and its shape is stabilized during the pretreatment. Therefore, various methods for maintaining the laminate can be selected during subsequent crosslinking.

[0184] There are no particular restrictions on the crosslinking treatment conditions, and it can be carried out under normal conditions. Preferably, it is carried out at 140°C to 180°C for 2 to 80 minutes using steam, pressure, oven, air bath, infrared radiation, microwave, lead-coated crosslinking, etc. More preferably, it is carried out at 150°C to 170°C for 5 to 60 minutes. The crosslinking treatment can be carried out in one crosslinking or two crosslinking processes.

[0185] The laminate of the present invention can be suitably manufactured, for example, by a method comprising a step of mixing rubber and carbon black to obtain a rubber composition, a step of laminating an uncrosslinked rubber layer obtained by molding the rubber composition to a fluoropolymer layer, and a step of crosslinking the laminated uncrosslinked rubber layer to the fluoropolymer layer. In the above manufacturing method, the conditions for the crosslinking treatment are the same as described above.

[0186] The mixing of rubber and carbon black can be carried out, for example, by mixing rubber and carbon black using a commonly used rubber mixing apparatus.

[0187] As a rubber mixing device, rollers, kneaders, Banbury mixers, internal mixers, twin-screw extruders, etc. can be used.

[0188] In addition to rubber and carbon black, other additives such as alkaline polyfunctional compounds, polytetrafluoroethylene, silica, crosslinking agents, and crosslinking auxiliaries can also be mixed together as needed.

[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 can be any one of the following methods: molding the uncrosslinked rubber layer and the fluororesin layer separately and then laminating them by means of pressing; molding the uncrosslinked rubber layer and the fluororesin layer simultaneously and then laminating them; or coating the uncrosslinked rubber layer with fluororesin to form the fluororesin layer.

[0191] In the method of laminating uncrosslinked rubber layer and fluororesin layer by means of compression bonding after molding them separately, the molding methods of rubber composition and fluororesin can be used separately.

[0192] Uncrosslinked rubber layers can be manufactured by molding rubber compositions into various shapes such as sheets and tubes using methods such as thermocompression molding, transfer molding, extrusion molding, injection molding, calendering, and coating. Commonly used polymer molding machines, such as injection molding machines, blow molding machines, extrusion molding machines, and various coating devices, can be used to produce laminates of various shapes, including sheets and tubes. Among these methods, extrusion molding is preferred from the perspective of superior productivity.

[0193] Fluoropolymer layers can be manufactured by molding fluoropolymers into various shapes, such as sheets and tubes, using methods such as compression molding, extrusion molding, injection molding, calendering, and coating (including powder coating). Commonly used polymer molding machines, such as injection molding machines, blow molding machines, extrusion molding machines, and various coating devices, can be used to produce laminates of various shapes, including sheets and tubes. Among these methods, extrusion molding is preferred for its superior productivity.

[0194] As a method for simultaneously molding and laminating an uncrosslinked rubber layer and a fluoropolymer layer, examples include using a rubber composition forming the rubber layer and a fluoropolymer forming the fluoropolymer layer, and molding and simultaneously laminating them using methods such as multilayer compression molding, multilayer transfer molding, multilayer extrusion molding, multilayer injection molding, and bilayer molding. In this method, since the uncrosslinked rubber layer and the fluoropolymer layer, as an uncrosslinked molded body, can be laminated simultaneously, a process for ensuring a tight bond between the uncrosslinked rubber layer and the fluoropolymer layer is not particularly necessary, and this method is also suitable for achieving a strong bond in subsequent crosslinking processes. If the bond is insufficient, a bonding process such as polishing can be performed. Among these methods, multilayer extrusion molding is preferred from the perspective of superior productivity.

[0195] (Laminated structure of a laminate)

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

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

[0198] For example, it can be a three-layer structure such as rubber layer (A) - fluoropolymer layer (B) - rubber layer (A) or fluoropolymer layer (B) - rubber layer (A) - fluoropolymer layer (B).

[0199] In addition, it can be a multilayer structure with three or more polymer layers (C) other than the rubber layer (A) and the fluoropolymer layer (B) bonded together. Polymer layers (D) can also be present on one or both sides of the multilayer structure with three polymer layers (C) other than the rubber layer (A) and the fluoropolymer layer (B) bonded together. The polymer layer (C) and the polymer layer (D) can be the same or different.

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

[0201] The polymer layers (C) and (D) can be rubber layers (C1) or (D1) other than the rubber layer (A). Examples of rubber layers (C1) or (D1) include non-fluorinated rubber layers (C1a) or (D1a) formed from non-fluorinated rubber. Non-fluorinated rubber is preferred due to its excellent cold resistance and cost-effectiveness. The non-fluorinated rubber layer (C1a) and the non-fluorinated rubber layer (D1a) can be formed from the same non-fluorinated rubber or from different non-fluorinated rubbers.

[0202] The laminate of the present invention can be laminated in the order of rubber layer (A) - fluoropolymer 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 following order: non-fluororubber layer (D1a) - rubber layer (A) - fluoropolymer layer (B) - non-fluororubber layer (C1a), rubber layer (A) - fluoropolymer layer (B) - non-fluororubber layer (D1a) - non-fluororubber layer (C1a), or rubber layer (A) - fluoropolymer layer (B) - non-fluororubber layer (C1a) - non-fluororubber layer (D1a).

[0204] Specific examples of non-fluorinated rubbers include nitrile rubber (NBR) or its hydrogenated form (HNBR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), butadiene rubber (BR), natural rubber (NR), isoprene rubber (IR), and other diene-based rubbers; ethylene-propylene terpolymer rubbers; silicone rubber; butyl rubber; epichlorohydrin rubber; acrylic rubbers; chlorinated polyethylene (CPE); polymer blends of nitrile rubber and vinyl chloride (PVC-NBR); ethylene propylene diene rubber (EPDM); and chlorosulfonated polyethylene (CSM). Additionally, rubbers made by mixing these non-fluorinated rubbers and fluorinated rubbers in any proportion can also be cited.

[0205] As a non-fluorinated rubber, diene-based rubber or epichlorohydrin rubber is preferred in terms 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] Furthermore, considering 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 mixtures thereof. It should be noted that crosslinking agents or other compounding agents may also be incorporated into the uncrosslinked rubber composition forming the rubber layers (C1) and (D1).

[0207] In the above-described layered structure, the laminate of the present invention is preferably constructed such that at least one surface of the laminate is formed by a rubber layer (A). In the laminate of the present invention, the rubber layer (A) is conductive, and the rubber layer (A) is firmly bonded to the fluoropolymer layer (B). Therefore, by utilizing the rubber layer (A) to form at least one surface of the laminate, it is possible to effectively prevent the laminate from becoming charged while imparting flexibility to the laminate. Furthermore, by firmly bonding the fluoropolymer layer (B) to the rubber layer (A), it is possible to sufficiently impart other properties such as low fuel permeability to the laminate.

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

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

[0210] Its basic structure is as follows: In the past, when the fluoropolymer layer (B) and the rubber layer (A) were laminated, the adhesion between the layers (fluororubber layer-fluoropolymer layer) was insufficient. Therefore, it was necessary to perform surface treatment on the resin side, or to apply an adhesive between the layers, or to roll up a strip film for fixation, which made the process complicated. However, the present invention does not require such complicated processes, but achieves chemically strong adhesion by cross-linking to produce cross-linked adhesion.

[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] In applications requiring a tight seal, such as joints in fuel piping systems, it is preferable to have rubber layers on both sides to maintain a tight seal. The inner and outer rubber layers can be of the same type or different types.

[0214] In the case of a three-layer structure of rubber layer (A) - fluoropolymer 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)-fluoropolymer layer (B)-rubber layer (C1), setting the fluororubber layer as the rubber layer (C1), and making the rubber layer (C1) the inner layer of the piping, the chemical resistance and fuel permeability can be improved.

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

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

[0218] (4) The three-layer structure of fluoropolymer layer (B)-rubber layer (A)-rubber layer (C1)

[0219] (5) Four or more floors

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

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

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

[0223] In addition, reinforcing layers such as reinforcing yarns can be appropriately added to improve pressure resistance.

[0224] In addition to excellent fuel permeability, the laminate of the present invention also exhibits excellent heat resistance, oil resistance, fuel oil resistance, LLC resistance, vapor resistance, weather resistance, and ozone resistance, and can fully withstand use under harsh conditions, making it suitable for a variety of applications.

[0225] For example, it is used in the engine body, main motion system, valve actuation system, lubrication and cooling system, fuel system, intake and exhaust system of automobile engines; transmission system of drive system; control system and braking system of chassis; basic electrical components, control system electrical components, equipment electrical components, etc. of electrical equipment, etc., requiring gaskets or non-contact and contact type gaskets (self-tightening seals, piston rings, open annular gaskets, mechanical seals, oil seal devices, etc.), bellows, diaphragms, hoses, pipes, wires, etc., with suitable characteristics for heat resistance, oil resistance, fuel oil resistance, LLC resistance, and vapor resistance.

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

[0227] Gaskets for the engine block, including cylinder head gaskets, cylinder head cover gaskets, oil pan gaskets, and general gaskets; O-rings, gaskets, timing belt cover gaskets, and other seals; control hoses and other hoses; vibration damping rubber for engine mounts; and sealing materials for high-pressure valves in the hydrogen storage system.

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

[0229] Valve stem seals, etc., for engine valves in valve-driven systems.

[0230] Oil cooler hoses, return hoses, and sealing gaskets for lubrication and cooling systems; water hoses around radiators; vacuum pump oil hoses for vacuum pumps, etc.

[0231] Fuel system components include fuel pump oil seals, diaphragms, valves, etc.; fuel hoses such as filler hoses, fuel supply hoses, fuel return hoses, and evaporation hoses; fuel tank built-in hoses, packing seals, tank gaskets, and built-in fuel pump assemblies; fuel piping components such as pipe bodies or connectors (O-rings); fuel injection devices such as injector gaskets, injector seals, injector O-rings, pressure regulator diaphragms, and inspection valves; carburetor needle valves, accelerator pump pistons, flange gaskets, and control hoses; and combined air control (CAC) valve seals and diaphragms. Among these, built-in hoses are suitable for use as fuel hoses and fuel tanks.

[0232] Intake manifold gaskets and exhaust manifold gaskets for intake and exhaust systems; diaphragms, control hoses, and emission control hoses for EGR (exhaust gas recirculation); diaphragms for BPT (battery purifier); afterburner seals for AB valves; throttle valve throttle gaskets; turbine oil hoses (supply), turbine oil hoses (return), turbine air hoses, internal cooler hoses, and turbine shaft seals for turbochargers.

[0233] Transmission system components such as bearings, seals, oil seals, O-rings, gaskets, torque converter hoses, etc.; transmission fluid hoses, ATF hoses, O-rings, gaskets, etc. for automatic transmissions.

[0234] Power steering fluid hoses for the control system, etc.

[0235] Oil seals, O-rings, gaskets, and brake oil hoses for braking systems; atmospheric valves, vacuum valves, and diaphragms for vacuum boosters; piston cups (rubber cups) for main cylinders; internal diameter seals, protective covers, etc.

[0236] Insulation or sheathing of wires (wire harnesses) for basic electrical components; tubing for external components of wire harnesses.

[0237] The coating material for various sensor wires in the electrical components of the control system, etc.

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

[0239] In addition to automotive applications, these gaskets can also be appropriately 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.; similar gaskets, O-rings, sealing materials, diaphragms, valves, hoses, rollers, tubes, chemical-resistant coatings, and linings in chemical equipment; fuel hoses and hoses used in small equipment such as lawnmowers; 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, rollers, and tubes in nuclear power plant equipment; similar gaskets, O-rings, hoses, sealing materials, diaphragms, valves, and tubes in OA equipment and general industrial components; similar gaskets, O-rings, hoses, sealing materials, diaphragms, valves, rollers, tubes, linings, spindles, wires, flexible joints, belts, rubber sheets, and weatherstripping in PPC copiers; and rollers and plates in PPC copiers. For example, the PTFE diaphragm's stop rubber material has poor sliding properties, which leads to 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] Furthermore, in applications involving food-grade rubber sealing materials, conventional rubber sealing materials have problems such as flavor contamination or rubber fragments entering the food. However, by using the laminate of the present invention, these problems can be mitigated, making it suitable for use. When rubber materials are used as sealing materials in piping systems employing rubber sealing material solvents for pharmaceutical and chemical applications, the rubber material suffers from solvent swelling. However, by using the laminate of the present invention, this problem can be mitigated by covering it with a resin. In general industrial applications, it can be appropriately used in applications such as rubber rollers, O-rings, gaskets, and sealing materials to improve the strength, slip properties, chemical resistance, and permeability of rubber materials. Particularly in applications involving sealing gaskets in lithium-ion batteries, it can simultaneously maintain both chemical resistance and sealing performance, making it suitable for use. It can also be appropriately used in other applications requiring low-friction slip properties.

[0241] In addition, examples of medical applications include suppositories, bottle cap seals, can seals, medication tapes, medication pads, syringe seals, transdermal absorption drug substrates, baby bottle nozzles, medical bags, catheters, infusion sets, mixing tubing, bottle cap gaskets, vacuum blood collection tube caps, syringe gaskets, infusion tubing, gaskets and caps for medical devices, syringe chips, port guards, blood collection tube caps, cap seals, gaskets, O-rings, sheath guides, dilators, guide sheaths, blood circuits, artificial heart-lung circuits, and rotational atherectomy. Rotablister tubing, indwelling needles, infusion sets, infusion tubing, closed infusion systems, infusion bags, blood bags, blood component separation tapes, tubing for blood component separation bags, artificial blood vessels, arterial cannulas, support frames, protective tubing for endoscopic procedures, endoscope body tubing, endoscope tip cannula, pharyngeal catheters, coronary artery bypass catheters, intestinal obstruction catheters, percutaneous transhepatic biliary drainage catheters, electrosurgical external cannula, ultrasonic scalpel external cannula, dissecting forceps external cannula, cell culture bags, etc.

[0242] In addition, examples of marine molded articles in which the present invention can be applied include pipes or hoses for subsea oil fields (including injection pipes and crude oil transport pipes).

[0243] Of these, laminates are particularly suitable for use as pipes or hoses. That is, laminates are preferably pipes or hoses. Among pipes or hoses, from the perspective of heat resistance and low fuel permeability, they can be appropriately used as fuel lines or hoses for automobiles.

[0244] The pipe or hose of the present invention preferably has a rubber layer (A) as the innermost layer. Since the rubber layer (A) is conductive, the flexibility of the laminate is improved by using the rubber layer (A) as the innermost layer, and the pipe or hose is less likely to become charged even when static electricity is generated due to the flow of fluid in the pipe or hose. Moreover, by having a fluoropolymer layer (B) firmly bonded to the rubber layer (A), other properties such as low fuel permeability of the pipe or hose are also excellent.

[0245] The embodiments have been described above, but it is understood that various changes in form and detail can be made without departing from the spirit and scope of the claims.

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

[0247] The rubber layer (A) is a conductive layer formed from a rubber composition containing rubber and carbon black. The content of carbon black in the rubber composition is 1.0 to 100 parts by weight relative to 100 parts by weight of the rubber, and the nitrogen adsorption specific surface area of ​​the carbon black is 140 m². 2 / g or less

[0248] The fluoropolymer layer (B) is formed from a fluoropolymer that can be melt-molded.

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

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

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

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

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

[0254] <7> According to a 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, a laminate based on any one of the first to seventh aspects is provided, wherein the rubber composition further contains a peroxide crosslinking agent.

[0256] <9> According to a ninth aspect of the present invention, a laminate based on any one of the first to eighth aspects is provided, wherein the rubber composition further comprises polytetrafluoroethylene, the specific surface area of ​​which is less than 8 m². 2 / g, the average particle size of the above polytetrafluoroethylene is 0.01μm~1000μm, and the melt viscosity of the above polytetrafluoroethylene at 380℃ 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> [[ID=Q1]]

[0267] Regarding the MFR of the CTFE / TFE / PPVE copolymer, a melt flow index measuring instrument (manufactured by Toyo Seiki Seisakusho Co., Ltd.) was used to measure 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.

[0268] <Fuel permeation coefficient>

[0269] The pellets of the CTFE / TFE / PPVE copolymer 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 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 thereto, and the mass change at 60 °C was measured for 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, and 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, and then about 3 mg of PTFE powder was put into an aluminum pan (a 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, and differential scanning calorimetry was carried out, and 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 product of (particle size) × (roundness) of silica>

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

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

[0281] The average primary particle size of carbon black is the arithmetic mean particle size, which is determined by observing the carbon black using an electron microscope.

[0282] <Nitrogen adsorption specific surface area of ​​carbon black>

[0283] According to JIS K 6217-2, it is determined by nitrogen adsorption using the S-BET formula.

[0284] <Adhesion strength of laminates>

[0285] The obtained laminate was cut into strips 10 mm wide × 40 mm long × 3 pieces to prepare sample pieces with gripping edges formed by peeling off the fluoropolymer sheet. For this sample piece, in order to measure the adhesive strength only at the adhesive surface excluding the interface between the rubber layer and the fluoropolymer layer, the gripping edge was increased by 2 mm to 3 mm by slowly pulling the interface between the rubber layer and the fluoropolymer layer apart once by hand. Then, a peel test was performed at 25°C and a tensile speed of 50 mm / min using an Autograph (Shimadzu Corporation AGS-J5kN) according to the method described in JIS-K-6256 (Test Method for Adhesion of Vulcanized Rubber). The adhesive strength was measured, and the average value of the obtained data with N=3 was calculated.

[0286] <Resistivity of the rubber layer>

[0287] A rubber sheet with a thickness of approximately 2 mm (before cross-linking) was cut and pressed at 170°C for 30 minutes to prepare a 4 cm × 7 cm sample sheet. Using a simulated insulation resistance meter 24060 (manufactured by Yokogawa Corporation), the probe tip was brought into contact with both ends of the sample sheet to measure the surface resistance value of the sample sheet when a voltage of 500 V was applied.

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

[0289] (Production of fluoropolymer sheets)

[0290] A fluoropolymer sheet (0.12 mm thick) was prepared by pressing a CTFE / TFE / PPVE copolymer with the following properties at 280°C for 10 minutes.

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

[0292] MFR = 29.2g / 10 minutes

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

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

[0295] The details of the materials used in the production of the rubber composition are shown below.

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

[0297] PTFE powder: TF9205, manufactured by 3M (PTFE micro powder, average particle size 7.7μm, specific surface area 1.6m²). 2 (g, melting point 327℃, melt viscosity 139 Pa·s)

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

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

[0300] Crosslinking agent: Peroxide crosslinking agent, PERHEXA25B, manufactured by Nippon Oil Company.

[0301] Basic polyfunctional compounds: N,N'-dicinnamyl-1,6-hexanediamine (V-3), carbon black manufactured by Daikin Industries: see Table 1 for details.

[0302] [Table 1]

[0303] Table 1

[0304]

[0305] The materials shown in Table 2 were mixed using an 8-inch open mill to obtain a sheet rubber composition (rubber sheet) with a thickness of approximately 2 mm.

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

[0307] (Fabrication of laminates)

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

[0309]

Claims

1. A laminate which is a laminate provided with a rubber layer (A) and a fluororesin layer (B) laminated on the rubber layer (A), wherein The rubber layer (A) is a layer having an electric conductivity, formed from a rubber composition containing a rubber and carbon black, the content of the carbon black in the rubber composition being 1.0 parts by mass to 100 parts by mass with respect to 100 parts by mass of the rubber, the specific surface area by nitrogen adsorption of the carbon black being 140 m 2 / g or less. the surface resistance value of the rubber layer (A) is 10 MΩ or less, the fluororesin layer (B) is formed of a fluororesin capable of melt molding.

2. The laminate according to claim 1, wherein the average primary particle diameter 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 is more than 8.0 parts by mass with respect to 100 parts by mass of the rubber.

4. The laminate according to claim 1 or 2, wherein The rubber is a fluororubber.

5. The laminate according to claim 1 or 2, wherein The fuel permeation coefficient of the fluororesin is 2.0 g-mm / m 2 / day or less.

6. The laminate according to claim 1 or 2, wherein The fluororesin is at least one selected from the group consisting of a chlorotrifluoroethylene-based copolymer and a tetrafluoroethylene / hexafluoropropylene / vinylidene fluoride copolymer.

7. The laminate according to claim 1 or 2, 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 with respect to 100 parts by mass of the rubber.

8. The laminate according to claim 1 or 2, wherein The rubber composition further contains a peroxide crosslinking agent.

9. The laminate according to claim 1 or 2, wherein The rubber composition further contains polytetrafluoroethylene having a specific surface area of less than 8 m 2 / g, an average particle diameter of 0.01 μm to 1000 μm, and a melt viscosity at 380°C of 1 x 10 1 Pa-s to 7 x 10 5 Pa-s.

10. The laminate according to claim 1 or 2, wherein The rubber composition further contains silica, and the average value of the product of "(particle diameter) x (roundness)" of the silica is 17.5 nm or more and 500 μm or less.

11. The laminate according to claim 1 or 2, wherein The rubber layer (A) and the fluororesin layer (B) are crosslinked and bonded.

12. The laminate according to claim 1 or 2, wherein The bonding strength of the rubber layer (A) and the fluororesin layer (B) is 5 N / cm or more.

13. The laminate according to claim 1 or 2, which is a tube or a hose.

Images