JP2010042669A - Fluororubber lamination and its production process - Google Patents

Abstract

The present invention provides a fluororubber-based laminate having both low fuel permeability suitable for fuel transportation hoses and the like, low-temperature embrittlement resistance, and excellent adhesion between a fluororubber layer and a non-fluororubber layer.
A laminate comprising a fluororubber layer (a) containing a fluororubber (a1) and a fluororesin (a2) and a non-fluororubber layer (b), wherein the fluororubber (a1) is vinylidene. A fluorine-containing copolymer having a mass ratio (a1) / (a2) of fluororubber (a1) to fluororesin (a2) in the fluororubber layer (a) of 60/40 to 97/3 Rubber laminate.
[Selection figure] None

Description

  The present invention relates to a fluororubber laminate in which a fluororubber layer (a) and a non-fluororubber layer (b) are laminated. A hose formed from such a laminate is particularly suitable as a fuel transport hose.

  Fluororubber is widely used in various fields such as the automobile industry, semiconductor industry, chemical industry and the like because it exhibits excellent chemical resistance, solvent resistance and heat resistance. It is used as hoses, sealing materials, etc. for devices, AT devices, fuel systems and peripheral devices. However, due to recent environmental regulations, these fluororubber materials are also required to be more severe in various properties such as aging resistance, weather resistance, processability, oil resistance, fuel oil resistance, and low fuel permeability. This is the current situation.

  Although fluororubber exhibits the above-mentioned excellent characteristics, its price is 10 to 20 times that of ordinary rubber materials, and it is a problem in terms of cost to make materials such as hoses using only fluororubber. was there. In addition, acrylonitrile-butadiene copolymer rubber, which has been used as a fuel transportation hose, is inferior to fluororubber in terms of various properties such as heat resistance, oil resistance, and aging resistance. It was requested.

  Therefore, hoses made of non-fluorinated rubber such as epichlorohydrin rubber have been developed as a thin layer using fluorine rubber as an inner layer (Patent Document 1). However, due to the recent increase in environmental awareness, legislation has been developed to prevent fuel volatilization. Especially in the automotive industry, there is a significant tendency to suppress fuel volatilization, especially in the United States, and there is a need for materials with excellent fuel low permeability. It is becoming larger, and thin fluororubber layers cannot meet such demands.

  A laminate in which a fluororubber layer and another rubber layer are bonded via a specific phosphonium salt is also known (Patent Document 2). However, fluororubber has a low fuel permeability lower than that of fluororesin, and if the fluorine content of the fluororubber is increased in order to improve the low fuel permeability, the low temperature embrittlement resistance is significantly lowered.

  In addition, it is known to mix a specific fluororesin in order to improve the low temperature embrittlement resistance of fluororubber (propylene-tetrafluoroethylene elastomer) (Patent Document 3).

International Publication No. 06/082843 Pamphlet JP-A-5-214118 JP 50-32244 A

  An object of the present invention is to provide a fluororubber laminate excellent in low fuel permeability, low temperature embrittlement resistance and excellent adhesion between a fluororubber layer and a non-fluororubber layer.

  The present invention is a laminate comprising a fluororubber layer (a) containing a fluororubber (a1) and a fluororesin (a2) and a non-fluororubber layer (b), wherein the fluororubber (a1) is vinylidene. It is a copolymer containing a fluoride (VdF) unit, and the mass ratio (a1) / (a2) of the fluororubber (a1) to the fluororesin (a2) in the fluororubber layer (a) is 60/40 to 97/3. The present invention relates to a fluororubber laminate.

  As fluororesin (a2) of fluororubber layer (a), tetrafluoroethylene (TFE) -hexafluoropropylene (HFP) copolymer, ethylene (E) -TFE copolymer, chlorotrifluoroethylene (CTFE)- A TFE copolymer, TFE-HFP-VdF copolymer or polyvinylidene fluoride (PVdF) is preferred from the viewpoint of good compatibility between the fluororubber (a1) and the fluororesin (a2).

  The non-fluorinated rubber in the non-fluorinated rubber layer (b) includes acrylonitrile-butadiene rubber or hydrogenated rubber thereof, blend rubber of acrylonitrile-butadiene rubber and polyvinyl chloride, epichlorohydrin rubber, ethylene-propylene rubber, chloro It is preferable that it consists of a sulfonated polyethylene rubber, a silicone rubber, or an acrylic rubber from the cost side of the laminated body obtained.

  The present invention also provides a fluororubber layer comprising a fluororubber (a1) and a fluororesin (a2) which are copolymers containing VdF units in a mass ratio (a1) / (a2) of 60/40 to 97/3 (a ) And a non-fluororubber layer (b) are also vulcanized and bonded to each other.

  In the production method of the present invention, after the vulcanizable fluororubber composition for forming the fluororubber layer (a) kneads the fluororubber (a1) and the fluororesin (a2) above the melting point of the fluororesin (a2). A vulcanizable fluororubber composition obtained by blending additives for other rubber compositions and kneading at a temperature lower than the vulcanization molding temperature is particularly excellent in resistance to low temperature embrittlement. To preferred.

  The present invention also relates to a molded article formed from the laminate of the present invention, and a fuel transport hose.

  According to the laminate of the present invention, it is possible to improve both low fuel permeability, low temperature embrittlement resistance, and adhesion between a fluororubber layer and a non-fluororubber layer.

The fluororubber laminate of the present invention is a laminate in which a fluororubber layer (a) containing a fluororubber (a1) and a fluororesin (a2) and a non-fluororubber layer (b) are laminated,
(I) the fluororubber (a1) is a copolymer containing VdF units;
(Ii) The mass ratio (a1) / (a2) of the fluororubber (a1) to the fluororesin (a2) in the fluororubber layer (a) is 60/40 to 97/3.

By using fluororubber (VdF fluoropolymer) containing VdF units, the adhesion between fluororubber (a1) and fluororesin (a2) is improved. As VdF type fluororubber, what is represented by Formula (1) is preferred.
^{- (M 1) - (M} 2) - (N 1) - (1)
(In the formula, the structural unit M ¹ is a structural unit derived from VdF (m ¹ ), the structural unit M ² is a structural unit derived from a fluorine-containing ethylenic monomer (m ² ), and the structural unit N ¹ is a single unit. (It is a repeating unit derived from monomer (n ¹ ) copolymerizable with monomer (m ¹ ) and monomer (m ² ))

Among the VdF type fluorine-containing rubbers represented by the formula (1) 30, the structural unit M ¹ 30 to 85 mol%, preferably not containing a structural unit M ² 70-15 mol%, more preferably a structural unit M ¹ 80 mol%, the structural unit M ² 70 to 20 mol%. The structural unit N ¹ is preferably 0 to 10 mol% with respect to the total amount of the structural unit M ¹ and the structural unit M ² .

Examples of the fluorine-containing ethylenic monomer (m ² ) include TFE, CTFE, trifluoroethylene, HFP, trifluoropropylene, tetrafluoropropylene, pentafluoropropylene, trifluorobutene, tetrafluoroisobutene, and perfluoro (alkyl vinyl ether). (Hereinafter also referred to as “PAVE”) and fluorine-containing monomers such as vinyl fluoride. Among these, TFE, HFP, and PAVE are preferable.

The monomer (n ¹ ) may be any monomer as long as it is copolymerizable with the monomer (m ¹ ) and the monomer (m ² ). For example, ethylene, propylene, alkyl vinyl ether, etc. can give.

Further, as the monomer (n ¹ ), a monomer that gives a crosslinking site may be used. As a monomer which gives such a crosslinking site, for example, formula (2):
CY ¹ ₂ = CY ¹ −R _f ¹ CHR ¹ X ¹ (2)
Wherein Y ¹ is a hydrogen atom, a fluorine atom or CH ₃ ; R _f ¹ is a fluoroalkylene group, a perfluoroalkylene group, a fluoropolyoxyalkylene group or a perfluoropolyoxyalkylene group; R ¹ is a hydrogen atom or CH ₃ X ¹ is an iodine atom or a bromine atom), or an iodine or bromine-containing monomer represented by formula (3):
_{CF 2 = CFO (CF 2 CF} (CF 3) O) m (CF 2) n -X 2 (3)
(Wherein, m is an integer of 0 to 5; n is an integer of 1 to 3; X ² is a cyano group, a carboxyl group, an alkoxycarbonyl group, a bromine atom or an iodine atom). These can be used alone or in any combination. The iodine atom, bromine atom, cyano group, carboxyl group, and alkoxycarbonyl group function as a crosslinking point.

  Among these, it is more preferable to use a fluororubber containing a VdF unit capable of polyol vulcanization and / or polyamine vulcanization from the viewpoint of good adhesion to the non-fluororubber layer (b) formed from the non-fluorine rubber composition. preferable.

  Specific examples of such VdF fluororubbers include VdF / HFP rubber, VdF / HFP / TFE rubber, VdF / CTFE rubber, VdF / CTFE / TFE rubber, VdF / PAVE rubber, VdF / Preferred are one or more of TFE / PAVE rubber, VdF / HFP / PAVE rubber, VdF / HFP / TFE / PAVE rubber, and the like.

  Among these VdF fluororubbers (a1), VdF / HFP rubber and VdF / HFP / TFE rubber are particularly preferable from the viewpoint of heat resistance, compression set, workability, and cost.

  The VdF fluororubber (a1) preferably has a number average molecular weight of 20,000 to 1,200,000, more preferably 30,000 to 300,000, and more preferably 50,000 to 200,000. Further preferably used.

  The VdF fluororubber (a1) used in the present invention is preferably a fluororubber having a fluorine content of 65% by mass or more, and more preferably a fluororubber having a fluorine content of 66% by mass or more. The upper limit of the fluorine content is not particularly limited, but is preferably 74% by mass or less. When the fluorine content is less than 65% by mass, chemical resistance, fuel oil resistance, and low fuel permeability tend to be inferior.

  The VdF-based fluororubber (a1) described above can be produced by a conventional method, and a known iodine transfer polymerization method is preferable. For example, a method of performing solution polymerization, and a perhaloolefin such as TFE, HFP, CTFE, PAVE and the like in the presence of an iodine compound, preferably a diiodine compound, in an aqueous medium substantially in the absence of oxygen. If necessary, there is a method in which emulsion polymerization is carried out in the presence of a radical initiator while stirring a monomer that gives a vulcanization site under pressure.

  Next, the fluororesin (a2) that is the other component constituting the fluororubber layer (a) will be described.

The fluororesin (a2) to be used is not particularly limited, but the fluororesin containing at least one fluorine-containing ethylenic polymer has compatibility with the VdF-based fluororubber (a1). It is preferable from a favorable point. The fluorinated ethylenic polymer preferably has a structural unit derived from at least one fluorinated ethylenic monomer. Examples of the fluorine-containing ethylenic monomer include tetrafluoroethylene (TFE) and formula (4):
CF ₂ = CF-R _f ² (4)
(Wherein R _f ² is —CF ₃ or —OR _f ³ (R _f ³ is a perfluoroalkyl group having 1 to 5 carbon atoms).
Perfluoroolefins such as perfluoroethylenically unsaturated compounds represented by: chlorotrifluoroethylene (CTFE), trifluoroethylene, hexafluoroisobutene, vinylidene fluoride (VdF), vinyl fluoride, formula (5):
CH ₂ = CX ³ (CF ₂ ) _n X ⁴ (5)
(Wherein X ³ represents a hydrogen atom or a fluorine atom, X ⁴ represents a hydrogen atom, a fluorine atom or a chlorine atom, and n represents an integer of 1 to 10)
And the like.

  The fluorine-containing ethylenic polymer may have a structural unit derived from a monomer copolymerizable with the fluorine-containing ethylenic monomer. Non-fluorinated ethylenic monomers other than fluoroolefins can be mentioned. Examples of the non-fluorine ethylenic monomer include ethylene, propylene, and alkyl vinyl ethers. Here, the alkyl vinyl ether refers to an alkyl vinyl ether having an alkyl group having 1 to 5 carbon atoms.

Among these, the following fluorine-containing ethylenic polymers are preferable from the viewpoint of good fuel low permeability and cold resistance of the obtained laminate.
(1) Ethylene / TFE copolymer (ETFE) consisting of TFE and ethylene
(2) TFE-perfluoro (alkyl vinyl ether) copolymer (PFA) or TFE / HFP copolymer (FEP) composed of TFE and a perfluoroethylenically unsaturated compound represented by formula (4)
(3) TFE / VdF / perfluoroethylenically unsaturated compound copolymer comprising TFE, VdF, and perfluoroethylenically unsaturated compound represented by formula (4) (4) polyvinylidene fluoride (PVdF)
(5) It is preferably any one of CTFE / TFE / perfluoroethylenically unsaturated compound copolymer comprising CTFE, TFE and a perfluoroethylenically unsaturated compound represented by formula (4), (1) The fluorine-containing ethylenic polymers represented by (2) and (5) are preferred.

  Next, preferred fluorine-containing ethylenic polymers (1), (2) and (5) will be described.

(1) ETFE
In the case of ETFE, in addition to the above-described effects, it is preferable in that mechanical properties and low fuel permeability are exhibited. The molar ratio of the TFE unit to the ethylene unit is preferably 20:80 to 90:10, more preferably 37:63 to 85:15, and particularly preferably 38:62 to 80:20. Moreover, the 3rd component may be contained and the kind will not be limited as long as it can copolymerize with TFE and ethylene as a 3rd component. As the third component, usually, the following formula CH ₂ = CX ⁵ R _f ³ , CF ₂ = CFR _f ³ , CF ₂ = CFOR _f ³ , CH ₂ = C (R _f ³ ) ₂
(Wherein X ⁵ represents a hydrogen atom or a fluorine atom, and R _f ³ represents a fluoroalkyl group optionally containing an etheric oxygen atom)
Among these, a fluorine-containing vinyl monomer represented by CH ₂ = CX ⁵ R _f ³ is more preferred, and a monomer having 1 to 8 carbon atoms in R _f ³ is particularly preferred.

Specific examples of the fluorine-containing vinyl monomer represented by the above formula include 1,1-dihydroperfluoropropene-1, 1,1-dihydroperfluorobutene-1, 1,1,5-trihydroperfluoropentene-1. 1,1,7-trihydroperfluoroheptene-1,1,1,2-trihydroperfluorohexene-1,1,1,2-trihydroperfluorooctene-1,2,2,3 3,4,4,5,5-octafluoropentyl vinyl ether, perfluoro (methyl vinyl ether), perfluoro (propyl vinyl ether), hexafluoropropene, perfluorobutene-1, 3,3,3-trifluoro-2- (trifluoromethyl) propene -1,2,3,3,4,4,5,5- heptafluoro-1-pentene (CH ₂ = CFCF ₂ CF ₂ CF ₂ H).

  The content of the third component is preferably from 0.1 to 10 mol%, more preferably from 0.1 to 5 mol%, particularly preferably from 0.2 to 4 mol%, based on the fluorine-containing ethylenic polymer.

(2) PFA or FEP
In the case of PFA or FEP, heat resistance is particularly excellent in the above-described effects, and it is preferable in that excellent low fuel permeability is exhibited in addition to the above-described effects. Although not particularly limited, it is preferably a copolymer composed of 70 to 99 mol% of TFE units and 1 to 30 mol% of perfluoroethylenically unsaturated compound units represented by the formula (4), and 80 to 97 TFE units. More preferably, the copolymer is composed of 3 to 20 mol% of a perfluoroethylenically unsaturated compound unit represented by mol% and the formula (4). If the TFE unit is less than 70 mol%, the mechanical properties tend to decrease, and if it exceeds 99 mol%, the melting point becomes too high and the moldability tends to decrease. Moreover, the fluorine-containing ethylenic polymer which consists of TFE and the perfluoroethylenically unsaturated compound represented by Formula (4) may contain the 3rd component, and TFE and Formula (4) are included as the 3rd component. The kind is not limited as long as it can be copolymerized with the perfluoroethylenically unsaturated compound represented by ().

(5) CTFE / TFE copolymer In the case of a CTFE / TFE copolymer, the molar ratio of CTFE units to TFE units is preferably CTFE: TFE = 2: 98 to 98: 2, 5:95 to More preferably, it is 90:10. If the CTFE unit is less than 2 mol%, the low fuel permeability tends to deteriorate and the melt processing tends to be difficult, and if it exceeds 98 mol%, the heat resistance and chemical resistance during molding may deteriorate. In addition, it is preferable to copolymerize a perfluoroethylenically unsaturated compound, and the perfluoroethylenically unsaturated compound unit is 0.1 to 10 mol% based on the total of the CTFE unit and the TFE unit, and the CTFE unit and TFE units are preferably 90 to 99.9 mol% in total. If the perfluoroethylenically unsaturated compound unit is less than 0.1 mol%, the moldability, environmental stress crack resistance and stress crack resistance tend to be poor, and if it exceeds 10 mol%, fuel low permeability, heat resistance, It tends to be inferior in mechanical properties and productivity.

  Of these, ETFE is preferred because it is particularly excellent in compatibility with the VdF-based fluororubber (a1).

  Moreover, it is preferable that it is 120-340 degreeC, as for melting | fusing point of a fluorine-containing ethylenic polymer, it is more preferable that it is 150-330 degreeC, and it is further more preferable that it is 170-320 degreeC. When the melting point of the fluorine-containing ethylenic polymer is less than 120 ° C., the fluororubber layer (a) tends to bleed out during vulcanization molding, and when it exceeds 340 ° C., the VdF-based fluoro rubber (a1) Mixing tends to be difficult.

The fuel permeability coefficient of the fluororesin is preferably 20 (g · mm) / (m ² · day) or less, more preferably 15 (g · mm) / (m ² · day) or less. (g · mm) / further preferably (m ² · day) or less, 5 (g · mm) / (m 2 · day) even more preferably at most. The lower limit value of the fuel permeability coefficient is not particularly limited, and the lower the value, the better.

  The fuel permeability coefficient can be measured by a method according to the cup method in the moisture permeability test method for moisture-proof packaging materials. Here, the cup method is a moisture permeability test method defined in JIS Z 0208, and is a method for measuring the amount of water vapor that passes through a membranous substance of a unit area in a certain time. In the present invention, the fuel permeation coefficient is measured according to this cup method.

  At least one polyfunctional compound (c) may be added to the fluororesin (a2) in order to improve adhesion to the VdF fluororubber (a1) or the non-fluororubber (b). The polyfunctional compound (c) is a compound having two or more functional groups having the same or different structures in one molecule.

  The functional group of the polyfunctional compound (c) is generally known to have reactivity such as a carbonyl group, a carboxyl group, a haloformyl group, an amide group, an olefin group, an amino group, an isocyanate group, a hydroxy group, and an epoxy group. Any functional group can be used. The compound having these functional groups is expected not only to have high affinity with the VdF-based fluororubber (a1) but also to react with the functional groups of the fluororesin (a2) to further improve the adhesion.

  The mass ratio (a1) / (a2) of the VdF-based fluororubber (a1) and the fluororesin (a2) in the fluororubber layer (a) is 60/40 to 97/3. If the fluororesin (a2) becomes too smaller than (a1) / (a2) = 97/3, the effect of improving the low fuel permeability and low temperature embrittlement resistance is reduced, while the fluororesin (a2) is reduced to (a1). ) / (A2) = over 60/40, the original rubber elasticity is remarkably impaired, the compression set is remarkably deteriorated, and the hardness is remarkably increased. (A1) / (a2) is preferably 65/35 to 95/5, more preferably 70/30 to 90/10 from the viewpoint of improving the low fuel permeability, low temperature embrittlement resistance and rubber elasticity in a balanced manner. .

  The fluororubber composition for forming the fluororubber layer (a) includes, in addition to the VdF fluororubber (a1) and fluororesin (a2), a vulcanizing agent, a vulcanization accelerator, a vulcanizing aid, Ordinary additives such as a vulcanizing agent and an acid acceptor are blended to prepare a composition for vulcanizing a fluororubber.

  The vulcanizing agent, the vulcanizing aid, the co-vulcanizing agent, and the vulcanization accelerator are used for vulcanizing the fluororubber. Here, vulcanization is to vulcanize the same or different polymer chains of fluororubber with a vulcanizing agent. By vulcanizing in this way, the fluororubber has improved tensile strength, It has good elasticity.

  The vulcanization system used in the present invention may be appropriately selected depending on the type of the cure site or the use of the obtained laminate when the vulcanizable group contains the vulcanizable group (cure site). As the crosslinking system, any of polyamine crosslinking system, polyol crosslinking system, peroxide crosslinking system, imidazole crosslinking system, triazine crosslinking system, oxazole crosslinking system, and thiazole crosslinking system can be adopted.

  Examples of vulcanizing agents include polyol vulcanizing agents, peroxide vulcanizing agents, polyamine vulcanizing agents, imidazole crosslinking vulcanizing agents, triazine crosslinking vulcanizing agents, oxazole crosslinking vulcanizing agents, and thiazole crosslinking vulcanizing agents. Any of the vulcanizing agents can be employed and may be used alone or in combination.

  Here, the vulcanized fluoro rubber obtained by vulcanization with a polyol-based vulcanizing agent is characterized by a small compression set and excellent heat resistance.

  A vulcanized fluoro rubber obtained by vulcanization with a peroxide vulcanizing agent is characterized by excellent chemical resistance and steam resistance as compared with polyol vulcanization and polyamine vulcanization.

  Vulcanized fluororubber vulcanized with a polyamine vulcanizing agent is characterized by excellent dynamic mechanical properties. However, compression set tends to be larger than that of vulcanized fluoro rubber vulcanized using a polyol vulcanizing agent or a peroxide vulcanizing agent.

  In the present invention, a polyol vulcanizing agent is preferably used for the fluororubber composition from the viewpoint of good adhesion to the non-fluororubber layer.

  As the vulcanizing agent in the present invention, polyamine-based, polyol-based and peroxide-based vulcanizing agents generally known for fluoro rubbers can be used.

  As the polyol-based vulcanizing agent, a compound conventionally known as a vulcanizing agent for fluororubber can be used. For example, a polyhydroxy compound, particularly, a polyhydroxy aromatic compound is preferable from the viewpoint of excellent heat resistance. Used.

  The polyhydroxy aromatic compound is not particularly limited. For example, bisphenol A, bisphenol AF, resorcin, 1,3-dihydroxybenzene, 1,7-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxy Naphthalene, 4,4′-dihydroxydiphenyl, 4,4′-dihydroxystilbene, 2,6-dihydroxyanthracene, hydroquinone, catechol, 2,2-bis (4-hydroxyphenyl) butane, 4,4-bis (4- Hydroxyphenyl) valeric acid, 2,2-bis (4-hydroxyphenyl) tetrafluorodichloropropane, 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxydiphenyl ketone, tri (4-hydroxyphenyl) methane, 3 , 3 ', 5, '- tetrachloro bisphenol A, 3,3', 5,5'-tetra-bromo-bisphenol A and the like. These polyhydroxy aromatic compounds may be an alkali metal salt, an alkaline earth metal salt, or the like, but when the copolymer is coagulated with an acid, it is preferable not to use the metal salt.

  Among these, a polyhydroxy compound is preferable from the viewpoint that the compression set of the vulcanized fluoro rubber is small and excellent in moldability, a polyhydroxy aromatic compound is more preferable because of excellent heat resistance, and bisphenol AF is further preferable.

  As a compounding quantity of a polyol vulcanizing agent, 0.2-10 mass parts is preferable with respect to 100 mass parts of fluororubber, 0.5-6 mass parts is more preferable, and 1-3 mass parts is further more preferable. If the vulcanizing agent is less than 0.2 parts by mass, the crosslinking density tends to be low and compression set tends to be large. If the vulcanizing agent exceeds 10 parts by mass, the crosslinking density becomes too high, and it tends to crack during compression. Tend.

  Moreover, it is preferable to use a vulcanization accelerator in combination with a polyol vulcanizing agent. When a vulcanization accelerator is used, the vulcanization reaction can be promoted by promoting the formation of an intramolecular double bond in the dehydrofluorination reaction of the fluororubber main chain.

  Although it does not specifically limit as a polyol type vulcanization accelerator, An onium salt can be used. Of these, quaternary ammonium salts and quaternary phosphonium salts are preferred, and 8-benzyl-1,8-diazabicyclo [5,4,0] -7-undecenium chloride (DBU-B) and / or benzyltriphenyl. It is more preferable to use phosphonium chloride (BTPPC) alone or in combination, and also in combination with other onium salts from the viewpoints of an appropriate vulcanization rate, normal physical properties of the molded product, and good compression set.

  Peroxide-based vulcanizing agents include organic peroxides. Generally, those that easily generate peroxy radicals in the presence of heat or a redox system, such as 1,1-bis ( t-butylperoxy) -3,5,5-trimethylcyclohexane, 2,5-dimethylhexane-2,5-dihydroxy peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide , Α, α′-bis (t-butylperoxy) -p-diisopropylbenzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5- Di (t-butylperoxy) hexyne-3, benzoyl peroxide, t-butylperoxybenzene, 2,5-dimethyl-2,5-di (benzoylperoxy) he Examples thereof include xane, t-butyl peroxymaleic acid, t-butyl peroxyisopropyl carbonate, and the like. Of these, preferred are dialkyl compounds. In general, the type and amount used are selected from the amount of active —O═O—, decomposition temperature and the like. The amount used is usually 0.1 to 15 parts by mass with respect to 100 parts by mass of the fluororubber, preferably 0.3 to 5 parts by mass.

When an organic peroxide is used, a vulcanization aid or a co-curing agent may be used in combination. The vulcanization aid or co-curing agent may be a compound having a reaction activity with respect to peroxy radicals and polymer radicals, for example, CH ₂ ═CH—, CH ₂ ═CHCH ₂ —, CF ₂ ═CF And a polyfunctional compound having a functional group such as-. Specifically, for example, triallyl cyanurate, triallyl isocyanurate (TAIC), trimethallyl isocyanurate, TAIC prepolymer, triacryl formal, triallyl trimellitate, N, N′-n-phenylenebismaleimide , Dipropargyl terephthalate, diallyl phthalate, tetraallyl terephthalate amide, triallyl phosphate, bismaleimide, fluorinated triallyl isocyanurate (1,3,5-tris (2,3,3-trifluoro-2-propenyl) -1 , 3,5-triazine-2,4,6-trione), tris (diallylamine) -S-triazine, triallyl phosphite, N, N-diallylacrylamide, 1,6-divinyldodecafluorohexane, hexaallyl phosphor Amide, N, N, N ′, N′-tetraallyltetraphthalamide, N, N, N ′, N′-tetraallylmalonamide, trivinyl isocyanurate, 2,4,6-trivinylmethyltrisiloxane, tri (5- Norbornene-2-methylene) cyanurate, triallyl phosphite and the like. Among these, TAIC is preferable from the viewpoint of vulcanizability and physical properties of the vulcanizate.

  As a compounding quantity of a peroxide type | system | group vulcanization adjuvant and a co-vulcanizing agent, 0.2-10 mass parts is preferable with respect to 100 mass parts of fluororubber, 0.5-6 mass parts is more preferable, 1- 5 parts by mass is more preferable. If the vulcanizing agent is less than 0.2 parts by mass, the crosslinking density tends to be low and compression set tends to be large. If the vulcanizing agent exceeds 10 parts by mass, the crosslinking density becomes too high, and it tends to crack during compression. Tend.

  Furthermore, an onium salt or an amine compound may be added in order to further improve the adhesion with the non-fluororubber layer (b).

  Moreover, usual additives blended in the fluororubber as necessary, for example, fillers, processing aids, plasticizers, colorants, stabilizers, adhesion aids, acid acceptors, mold release agents, imparting conductivity Various additives such as additives, thermal conductivity imparting agents, surface non-tackiness imparting agents, flexibility imparting agents, heat resistance improving agents, flame retardants and the like can be blended, and conventional vulcanizing agents different from those described above Or one or more vulcanization accelerators may be blended.

  The vulcanizable fluororubber composition for the fluororubber layer (a) in the present invention comprises a VdF fluororubber (a1), a fluororesin (a2), a vulcanizing agent, a vulcanizing aid, a co-vulcanizing agent, and a vulcanizing agent. It can be obtained by kneading accelerators, onium salts and / or other compounding agents such as amine compounds and fillers.

  Especially, low-temperature embrittlement resistance improves by melt-kneading VdF type fluororubber (a1) and fluororesin (a2) beforehand more than melting | fusing point of fluororesin (a2).

  The melt kneading is performed by kneading with the fluororubber (a1) at a melting point of the fluororesin (a2) or higher, for example, 200 ° C or higher, usually 250 to 300 ° C, using a Banbury mixer, a pressure kneader, an extruder or the like. be able to. Among these, it is preferable to use an extruder such as a pressure kneader or a twin screw extruder because a high shear force can be applied.

  Here, there is a process (dynamic crosslinking) in which fluororubber is vulcanized in a fluororesin under the melt condition of the fluororesin as a process similar to the melt kneading in the present invention. The dynamic cross-linking and the melt kneading in the present invention are the dynamic cross-linking in which rubber is blended in a thermoplastic matrix, the rubber is cross-linked while kneading, and the cross-linked rubber is dispersed microscopically in the matrix. Although it is a method, the melt-kneading in the present invention is a melt-kneading under conditions that do not cause vulcanization (the absence of components necessary for vulcanization, or a blend that does not cause a vulcanization reaction at that temperature), The matrix is essentially unvulcanized rubber, which is essentially different in that it is a mixture in which the fluororesin is uniformly dispersed in the unvulcanized rubber.

  Melting and kneading of the fluororubber (a1) and the fluororesin (a2) is not performed under conditions that cause vulcanization at that temperature (such as in the presence of a vulcanizing agent, a vulcanization accelerator, and an acid acceptor). Components that do not cause vulcanization at a melt kneading temperature equal to or higher than the melting point of a2) (for example, only a specific vulcanizing agent, only a combination of a vulcanizing agent and a vulcanization accelerator, etc.) may be added and mixed. In addition, the combination of a vulcanizing agent, a vulcanization accelerator, and an acid acceptor causes vulcanization at a temperature equal to or higher than the melting point of the fluororesin (a2).

  The fluororubber premix obtained by melt kneading in the present invention has a structure in which the VdF fluororubber (a1) forms a continuous phase and the fluororesin (a2) forms a dispersed phase, or a VdF fluororubber ( It is presumed that a1) and the fluororesin (a2) both have a structure forming a continuous phase.

  By forming such a structure, in the fluororubber layer (a), the effect of lowering the fuel permeability by the fluororesin (a2) can be sufficiently and uniformly exhibited, and as described above, the low temperature embrittlement resistance is also exhibited. It is thought that it will greatly improve.

  The melt-kneaded premix of the VdF-based fluororubber (a1) and the fluororesin (a2) is then vulcanized with other additives such as a vulcanizing agent, a vulcanization accelerator, and a filler as necessary. The vulcanized fluororubber composition (full compound) for the fluororubber layer (a) is produced by kneading at a decomposition temperature of 100 ° C or lower.

  The fluororubber layer (a) may be vulcanized alone before being laminated with the non-fluororubber layer (b), or may be vulcanized simultaneously after laminating the non-fluororubber layer (b).

  Next, the non-fluorinated rubber layer (b) will be described.

  The non-fluorine rubber in the non-fluororubber layer (b) is not particularly limited, but acrylonitrile-butadiene rubber and its hydrogenated product, polyvinyl chloride additive of acrylonitrile-butadiene rubber, styrene-butadiene rubber, poly Chloroprene, ethylene-propylene-termonomer copolymer, chlorinated polystyrene, chlorosulfonated polystyrene rubber, chlorosulfonated polyethylene rubber, silicone rubber, butyl rubber, epichlorohydrin rubber, acrylic rubber, ethylene-vinyl acetate copolymer, Examples include α, β-unsaturated nitrile-conjugated diene copolymer rubbers or hydrides thereof. Among these, acrylonitrile-butadiene rubber is preferable because of its good heat resistance, oil resistance, weather resistance, and extrusion moldability. , Epichlorohydrin rubber Or a silicone rubber.

  Moreover, it is preferable that non-fluorine rubber is a rubber | gum which can be peroxide vulcanized from the point that adhesiveness with a fluororubber layer (a) is favorable.

  Further, from the viewpoint of improving adhesive strength with other materials, at least one compound selected from the group consisting of an onium salt, an amine compound, and an epoxy resin may be blended in the non-fluororubber. In these, it is preferable that an epoxy resin is mix | blended with non-fluororubber at the point which can improve adhesive force. The onium salt and the amine compound are not particularly limited, and examples thereof include a quaternary ammonium salt, a quaternary phosphonium salt, an oxonium salt, a sulfonium salt, a cyclic amine, a monofunctional amine compound, and a bifunctional amine compound. . From the viewpoint of adhesiveness to the fluororubber layer, the amine compound and / or onium salt that is preferably blended in the fluororubber is more preferably N, N-dicinnamylidene-1,6-hexamethylenediamine or tetra n-Butylphosphonium benzotriazolate.

で表わされる化合物等があげられる。ここで、式（１０）において、ｎは０．１〜３が好ましく、０．１〜０．５がより好ましく、０．１〜０．３がさらに好ましい。ｎが０．１未満であると、他材との接着力の向上効果が小さくなる傾向がある。一方、ｎが３をこえると、粘度が高くなり、ゴム中での均一な分散が困難になる傾向がある。 Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, and polyfunctional epoxy resin. Of these, the bisphenol A type epoxy resin has the formula (10):

And the like. Here, in Formula (10), n is preferably 0.1 to 3, more preferably 0.1 to 0.5, and still more preferably 0.1 to 0.3. If n is less than 0.1, the effect of improving the adhesive strength with other materials tends to be small. On the other hand, when n exceeds 3, the viscosity increases, and uniform dispersion in the rubber tends to be difficult.

  0.1-20 mass parts is preferable with respect to 100 mass parts of non-fluororubbers, as for the compounding quantity of an epoxy resin, 0.5-15 mass parts is more preferable, and 1-10 mass parts is more preferable. When the compounding amount of the epoxy resin is less than 0.1 parts by mass, the effect of improving the adhesive strength with other materials tends to be small. On the other hand, when the compounding quantity of an epoxy resin exceeds 20 mass parts, there exists a tendency for the softness | flexibility of a non-fluororubber layer to be impaired.

  As the vulcanizing agent, any vulcanizing agent used for ordinary non-fluorinated rubber can be used. For example, sulfur vulcanizing agent, peroxide vulcanizing agent, polythiol vulcanizing agent, quinoid vulcanizing agent, resin vulcanizing agent, metal oxide, diamine vulcanizing agent, polythiols, 2-mercaptoimidazoline Among these, vulcanizing agents such as peroxide vulcanizing agents are preferable from the viewpoint of adhesive properties.

  As a compounding quantity of the vulcanizing agent mix | blended in the composition for vulcanization | cure for non-fluororubber layers (b), 0.2-10 mass parts is preferable with respect to 100 mass parts of non-fluororubbers, and 0.0. 5-8 mass parts is more preferable. If the vulcanizing agent is less than 0.2 parts by mass, the vulcanization density tends to be low and the compression set tends to be large. If the vulcanizing agent exceeds 10 parts by mass, the vulcanization density becomes too high and cracks occur during compression. It tends to be easier.

  Further, the non-fluorine rubber composition may contain a vulcanization accelerator in addition to the non-fluorine rubber and the vulcanizing agent, and further, if necessary, an acid acceptor, a reinforcing agent, a filler, a plasticizer. Additives commonly used in the art such as agents and anti-aging agents can be added.

  The non-fluorinated rubber composition can be obtained by kneading using a generally used rubber kneading apparatus.

The following method can be adopted as a method for laminating the laminate of the present invention.
(1) A method of vulcanizing and bonding the unvulcanized fluororubber layer (a) and the unvulcanized non-fluororubber layer (b). Specifically, a vulcanized fluororubber composition and a vulcanized non-fluororubber composition are coextruded in two layers by an extruder, or an outer layer is extruded onto an inner layer by two extruders. An example is a method in which an unvulcanized laminate comprising an inner layer and an outer layer is extruded and integrated by an extruder, and then vulcanized and bonded.
(2) A method in which one of the fluororubber layer (a) and the non-fluororubber layer (b) is vulcanized, and then the other layers are stacked, pressure vulcanized, and laminated.
(3) A method in which a vulcanized fluoro rubber layer (a) and a vulcanized non-fluoro rubber layer (b) are bonded and laminated using an adhesive.

  Examples of the adhesive include acid anhydride-modified products of diene polymers; acid anhydride-modified products of polyolefins; polymer polyols (for example, glycol compounds such as ethylene glycol and propylene glycol, and dibasic acids such as adipic acid. Polyester polyol obtained by condensation; partially saponified product of copolymer of vinyl acetate and vinyl chloride, and polyisocyanate compound (for example, glycol compound such as 1,6-hexamethylene glycol and 2,4-tolylene diisocyanate) Reaction mixture of a diisocyanate compound with a molar ratio of 1: 2; a mixture of a triol compound such as trimethylolpropane and a diisocyanate compound such as 2,4-tolylene diisocyanate with a molar ratio of 1: 3) A known adhesive such as can be used.

  Of these laminating methods, the vulcanization adhesion method (1) is preferable because of its high degree of freedom in processing.

  The vulcanization conditions may be determined as appropriate depending on the type of vulcanizing agent to be used, but are usually performed by heating at a temperature of 150 to 300 ° C. for 1 minute to 24 hours.

  In addition, as a vulcanization method, vulcanization under normal conditions, such as steam vulcanization, as well as under normal pressure, increased pressure, reduced pressure, and in air, under any conditions. The reaction can be performed.

  In the laminate of the present invention, the thickness of the fluororubber layer (a) is not particularly limited. However, since the fuel has low fuel permeability, the laminate such as a fuel transport hose can be made thinner than the conventional one. Therefore, it is advantageous in terms of weight, size, and cost.

  Moreover, since the low-temperature embrittlement resistance of the fluororubber layer (a) is improved, the thickness of the non-fluororubber layer (b) can be made thinner than before.

  The laminate of the present invention is a laminate having both low fuel permeability, low temperature embrittlement resistance, chemical resistance, oil resistance, and heat resistance, and is useful as a hose, container, sealing material, etc. around the fuel. Is useful as a fuel transport hose (tube) for automobile engines and peripheral devices, AT devices, fuel systems and peripheral devices.

  A fuel transport hose (tube) has a laminated structure in which a fluororubber layer (a) is disposed in a tubular innermost layer and a non-fluororubber layer (b) is disposed in an outer layer thereof. An adhesive layer may be interposed between the rubber layer (a) and the non-fluorine rubber layer (b).

  Such a fuel transport hose (tube) of the present invention is excellent in the effect of the above-described laminate of the present invention, that is, low fuel permeability, so that the thickness of the fluororubber layer can be made thinner than before. Moreover, since the low-temperature embrittlement resistance of the fluororubber layer (a) is improved, the thickness of the non-fluororubber layer (b) can be made thinner than before. As a result, the hose itself is advantageous in terms of weight, size, and cost.

  The use of the laminate of the present invention is not particularly limited. For example, in addition to the above-described fuel transport hose, an engine body of an automobile engine, a main motion system, a valve system, a lubricant / cooling system, a fuel system, an intake / Exhaust system; Drive system transmission system; Chassis steering system; Brake system; Heat resistance, oil resistance, fuel oil resistance, anti-freezing liquid resistance for engine cooling, such as basic electrical parts of control equipment, control system electrical parts, electrical equipment parts -Seal materials such as gaskets that require steam resistance and non-contact type and contact type packings (self seal packing, piston ring, split ring type packing, mechanical seal, oil seal, etc.).

  The sealing material used in the engine body of the automobile engine is not particularly limited. For example, a cylinder head gasket, a cylinder head cover gasket, an oil pan packing, a gasket such as a general gasket, an O-ring, a packing, a timing belt cover gasket, etc. For example, a sealing material.

  The seal material used in the main motion system of the automobile engine is not particularly limited, and examples thereof include a shaft seal such as a crankshaft seal and a camshaft seal.

  The seal material used in the valve system of the automobile engine is not particularly limited, and examples thereof include a valve stem oil seal of an engine valve.

  The seal material used in the lubricant / cooling system of the automobile engine is not particularly limited, and examples thereof include an engine oil cooler seal gasket.

  The sealing material used for the fuel system of the automobile engine is not particularly limited. For example, fuel such as a fuel pump oil seal, a fuel tank filler seal, a tank packing, a fuel tube connector O link, etc. Examples thereof include an injector cushion ring, an injector seal ring, an injector O-ring, and a flange gasket of a carburetor.

  The sealing material used for the intake / exhaust system of the automobile engine is not particularly limited. For example, the intake manifold packing of the manifold, the exhaust manifold packing, the throttle body packing of the throttle, the turbine shaft seal of the turbo charge, etc. Can be given.

  The sealing material used in the transmission system of the automobile is not particularly limited, and examples thereof include a bearing seal, an oil seal, an O-ring, and a packing related to a transmission, and an O-ring and packing of an automatic transmission. .

  The sealing material used in the brake system of the automobile is not particularly limited. For example, oil seals, O-rings, packing, piston cylinders (rubber cups) of master cylinders, caliper seals, boots, etc. can give.

  The sealing material used for the electrical equipment of the automobile is not particularly limited, and examples thereof include an O-ring and a packing of a car air conditioner.

  Applications other than those for automobiles are not particularly limited, for example, oil-resistant, chemical-resistant, heat-resistant, steam- or weather-resistant packings, O-rings, and other sealing materials in transportation such as ships and airplanes; Packing, O-rings, sealing materials for food plants, and similar packings, O-rings, sealing materials for food plant equipment (including household products); similar packings, O-rings, sealing materials for nuclear plant equipment; The same packing, O-ring, sealing material and the like can be mentioned.

  Next, the present invention will be described with reference to examples, but the present invention is not limited to such examples.

  Various characteristics in this specification were measured by the following methods.

(1) Fuel permeation coefficient CE10 (toluene / isooctane / ethanol = 45/45/10 vol%) as a simulated fuel is placed in a SUS container (open area 1.26 × 10 ⁻³ m ² ) having a volume of 20 mL. Put 18 mL, and set the sheet-like test piece in the container open part and seal it to make a test body. The test body is placed in a thermostatic device (60 ° C.), the weight of the test body is measured, and when the weight reduction per unit time becomes constant, the fuel permeability coefficient is obtained by the following formula.

(2) Embrittlement temperature Measured according to JIS K6261.

(3) Tensile strength at break Measured according to JIS K6251.

(4) Tensile elongation at break Measured according to JIS K6251.

(5) Hardness (Shore A)
Measured with durometer type A according to JIS K6253.

Moreover, each brand name in a table | surface and specification is each shown below.
Fluoro rubber 1: A ternary fluoro rubber capable of polyol vulcanization (VdF / TFE / HFP = 58/20/22 mol%). The Mooney viscosity ML1 + 10 (100 ° C.) is about 47.
Fluoro rubber 2 (pre-compound): 100 parts by mass of fluoro rubber 1 was put into a pressure kneader, and then 2.2 parts by mass of bisphenol AF (vulcanizing agent 1) and 8-benzyl-1,8-diazabicyclo [5 , 4,0] -7-Undecenium chloride (vulcanization accelerator 1) 0.56 parts by mass, and a fluororubber pre-compound obtained by kneading at a rubber fabric temperature of 140 to 150 ° C. for 12 minutes.
Fluoro rubber 3: A ternary fluoro rubber (VdF / TFE / HFP = 50/20/30 mol%) capable of polyol vulcanization. The Mooney viscosity ML1 + 10 (100 ° C.) is about 85.
Fluoro rubber 4 (pre-compound): 100 parts by mass of fluoro rubber 3 is charged into a pressure kneader, and then 2.2 parts by mass of bisphenol AF (vulcanizing agent 1) and 8-benzyl-1,8-diazabicyclo [5 , 4,0] -7-Undecenium chloride (vulcanization accelerator 1) 0.56 parts by mass, and a fluororubber pre-compound obtained by kneading at a rubber fabric temperature of 140 to 150 ° C. for 12 minutes.
Fluoro rubber 5: Fluorine-containing propylene rubber capable of peroxide vulcanization (AFLAS 150P manufactured by Asahi Glass Co., Ltd.)
Fluororesin 1: TFE / ethylene / 2,3,4,4,5,5-heptafluoro-1-pentene = 63.4 / 34.2 / 2.4 mol% copolymer (ETFE. Melting point) : 225 ° C)
Fluororesin 2: TFE / HFP / perfluoro (propyl vinyl ether) = 91.9 / 7.7 / 0.4 mol% copolymer (FEP. Melting point: 260 ° C.).
Fluororesin 3: 46/44 / 9.5 / 0.5 mol% copolymer of TFE / ethylene / HFP / 2,3,3,4,4,5,5-heptafluoro-1-pentene (EFEP Melting point: 195 ° C)
Vulcanizing agent 1: Bisphenol AF
Vulcanizing agent 2: 1,3-bis (t-butylperoxyisopropyl) benzene (Perkadox 14 manufactured by Kayaku Akzo Co., Ltd.)
Vulcanization accelerator 1: 8-benzyl-1,8-diazabicyclo [5,4,0] -7-undecenium chloride vulcanization auxiliary 1: triallyl isocyanurate (Taike made by Nippon Kasei Co., Ltd.)
Filler 1: Carbon black (Seast-S manufactured by Tokai Carbon Co., Ltd.)
Filler 2: Carbon black (MT carbon manufactured by Cancarb: N990)
Filler 3: Magnesium oxide (MA150 manufactured by Kyowa Chemical Industry Co., Ltd.)
Acid acceptor 1: calcium hydroxide (CALDIC2000 manufactured by Omi Chemical Co., Ltd.)
Non-fluorinated rubber 1: acrylonitrile-butadiene rubber (NBR) (a rubber composition comprising NIPOL 1041L manufactured by Nippon Zeon Co., Ltd. (43 parts by mass of carbon black, 7 parts by mass of zinc oxide, 100 parts by mass of wet silica, wet silica) 21 parts by weight, stearic acid 1.4 parts by weight, anti-aging agent 3 parts by weight, plasticizer 21 parts by weight, peroxide 3 parts by weight) 100 parts by weight JER828 (made by Japan Epoxy Resin Co., Ltd.) 6 Compound obtained by kneading 6 parts by mass of V-3 (manufactured by Daikin Industries, Ltd.)

Production Example 1 (Production of fluororubber layer (a))
(Preparation of melt-kneaded premix)
100 parts by mass of fluororubber 1 and 5 parts by mass of fluororesin 1 are charged into a pressure type kneader having an internal volume of 3 liters, and melt kneaded for 30 minutes at a temperature of 230 ° C., which is not lower than the melting point of fluororesin 1 (225 ° C.). A mixture was prepared. The rotation speed of the rotor was 30 rpm.

(Preparation of full compound)
The obtained preliminary mixture was charged into a pressure type kneader, 2 parts by mass of vulcanizing agent 1 and 0.55 parts by mass of vulcanization accelerator 1 were added, and kneaded for 12 minutes at a temperature of 140 to 150 ° C. After taking out the rubber fabric and cooling for 24 hours, 13 parts by mass of filler 1, 6 parts by mass of acid acceptor 1, 3 parts by mass of filler 3 were added, and an open roll equipped with two 8-inch rolls was used. And kneading at 30 to 80 ° C. for 20 minutes.

(Manufacture of fluororubber layer (a))
The resulting full compound was placed at room temperature for about 24 hours and then kneaded again with the same open roll, and finally formed into an unvulcanized fluororubber sheet having a thickness of 3 mm.

  Further, this unvulcanized sheet was press vulcanized with a mold at 160 ° C. for 45 minutes to obtain a vulcanized fluoro rubber sheet for a fluoro rubber layer (a) having a thickness of 2 mm and 0.5 mm.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 1.

Production Example 2 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) was prepared by pre-melting kneading and full compounding in the same manner as in Production Example 1 except that the blending amount of the fluororesin 1 was 10 parts by mass.

  Further, press vulcanization was conducted in the same manner as in Production Example 1 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 1.

Production Example 3 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) is prepared by pre-melt kneading and full compounding in the same manner as in Production Example 1 except that 10 parts by mass of fluororesin 2 is used instead of fluororesin 1. Prepared.

  Further, press vulcanization was conducted in the same manner as in Production Example 1 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 1.

Production Example 4 (Production of fluororubber layer (a))
(Preparation of melt-kneaded premix)
100 parts by mass of fluororubber 2 (pre-compound) and 5 parts by mass of fluororesin 1 are put into a pressure type kneader having an internal volume of 3 liters, and melted at a temperature of 230 ° C. above the melting point (225 ° C.) of fluororesin 1 for 30 minutes. The mixture was kneaded to prepare a premix. The rotation speed of the rotor was 30 rpm.

(Preparation of full compound)
Using the open roll provided with two 8-inch rolls, 13-80 parts by weight of filler 1, 6 parts by weight of acid acceptor 1 and 3 parts by weight of filler 3 were added to the resulting premix, 30-80 The mixture was kneaded at 20 ° C. for 20 minutes.

(Manufacture of fluororubber layer (a))
The resulting full compound was placed at room temperature for about 24 hours and then kneaded again with the same open roll, and finally formed into an unvulcanized fluororubber sheet having a thickness of 3 mm.

  Further, this unvulcanized sheet was press-vulcanized with a mold at 160 ° C. for 45 minutes to obtain a vulcanized fluoro rubber sheet for a fluoro rubber layer (a) having a thickness of 2 mm and 0.5 mm.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 1.

Production Example 5 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) was prepared by pre-melt kneading and full compounding in the same manner as in Production Example 4 except that 10 parts by mass of the fluororesin 1 was used.

  Further, press vulcanization was conducted in the same manner as in Production Example 4 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 1.

Production Example 6 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) is prepared by pre-melt kneading and full compounding in the same manner as in Production Example 4 except that 10 parts by mass of fluororesin 2 is used instead of fluororesin 1. Prepared.

  Further, press vulcanization was conducted in the same manner as in Production Example 4 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 1.

Comparative Production Example 1 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) was prepared by full compounding in the same manner as in Production Example 4 except that the fluororesin 1 was not blended and a melt-kneaded premix was not prepared.

  Further, press vulcanization was conducted in the same manner as in Production Example 4 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 1.

Production Example 7 (Production of fluororubber layer (a))
(Preparation of melt-kneaded premix)
70 parts by mass of fluororubber 3 and 30 parts by mass of fluororesin 1 are put into a pressure type kneader having an internal volume of 3 liters and melt-kneaded for 30 minutes at a temperature of 230 ° C. which is not lower than the melting point (225 ° C.) of fluororesin 1. A mixture was prepared. The rotation speed of the rotor was 30 rpm.

(Preparation of full compound)
The obtained preliminary mixture was charged into a pressure type kneader, 2 parts by mass of vulcanizing agent 1 and 0.55 parts by mass of vulcanization accelerator 1 were added, and kneaded for 12 minutes at a temperature of 140 to 150 ° C. After taking out the rubber fabric and cooling it for 24 hours, 13 parts by mass of filler 2, 6 parts by mass of acid acceptor 1, 3 parts by mass of filler 3 were added, and an open roll equipped with two 8-inch rolls was used. And kneading at 30 to 80 ° C. for 20 minutes.

(Manufacture of fluororubber layer (a))
The resulting full compound was placed at room temperature for about 24 hours and then kneaded again with the same open roll, and finally formed into an unvulcanized fluororubber sheet having a thickness of 3 mm.

  Further, this unvulcanized sheet was press-vulcanized with a mold at 180 ° C. for 20 minutes to obtain a vulcanized fluoro rubber sheet for a fluoro rubber layer (a) having a thickness of 2 mm and 0.5 mm.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 2.

Production Example 8 (Production of fluororubber layer (a))
(Preparation of melt-kneaded premix)
70 parts by mass of fluororubber 4 (pre-compound) and 30 parts by mass of fluororesin 1 are charged into a pressure type kneader having an internal volume of 3 liters and melted for 30 minutes at a temperature of 230 ° C. above the melting point (225 ° C.) of fluororesin 1 The mixture was kneaded to prepare a premix. The rotation speed of the rotor was 30 rpm.

(Preparation of full compound)
13-80 parts by mass of the filler 2, 6 parts by mass of the acid acceptor 1 and 3 parts by mass of the filler 3 were added to the obtained preliminary mixture, and an open roll having two 8-inch rolls was used. The mixture was kneaded at 20 ° C. for 20 minutes.

(Manufacture of fluororubber layer (a))
The resulting full compound was placed at room temperature for about 24 hours and then kneaded again with the same open roll, and finally formed into an unvulcanized fluororubber sheet having a thickness of 3 mm.

  Further, this unvulcanized sheet was press-vulcanized with a mold at 180 ° C. for 20 minutes to obtain a vulcanized fluoro rubber sheet for a fluoro rubber layer (a) having a thickness of 2 mm and 0.5 mm.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 2.

Production Example 9 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) is prepared by pre-melting and kneading and full compounding in the same manner as in Production Example 7 except that 30 parts by mass of fluororesin 2 is used instead of fluororesin 1. Prepared.

  Further, press vulcanization was conducted in the same manner as in Production Example 7 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 2.

Production Example 10 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) is prepared by pre-melting and kneading and full compounding in the same manner as in Production Example 7, except that 30 parts by mass of fluororesin 3 is used instead of fluororesin 1. Prepared.

  Further, press vulcanization was conducted in the same manner as in Production Example 7 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 2.

Comparative Production Example 2 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) was prepared by full compounding in the same manner as in Production Example 8 except that the fluororesin 1 was not blended and a melt-kneaded premix was not prepared.

  Further, press vulcanization was conducted in the same manner as in Production Example 8 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 2.

  From the results of Tables 1 and 2, the fuel permeation coefficient is reduced by using a fluororubber layer containing a fluororesin as the fluororubber layer, and the low temperature embrittlement temperature is reduced by using ETFE and EFEP as the fluororesin. It can be seen that it can be greatly reduced (becomes less brittle at low temperatures).

Production Example 11 (Production of fluororubber layer (a))
Pre-melt kneading and full compounding were carried out in the same manner as in Production Example 9 with the composition shown in Table 3 to prepare an unvulcanized fluoro rubber sheet for the fluoro rubber layer (a).

  Further, press vulcanization was conducted in the same manner as in Production Example 9 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 3.

Comparative Production Example 3 (Production of fluororubber layer (a))
An unvulcanized fluororubber sheet for the fluororubber layer (a) was prepared by full compounding in the same manner as in Production Example 11 except that the fluororesin 2 was not blended and a melt-kneaded premix was not prepared.

  Further, press vulcanization was conducted in the same manner as in Production Example 11 to obtain a vulcanized fluoro rubber sheet.

  The obtained vulcanized fluoro rubber sheet was examined for fuel permeability coefficient, embrittlement temperature, tensile breaking strength, tensile breaking elongation, and hardness. The results are shown in Table 3.

Production Example 12 (Production of non-fluororubber layer (b))
100 parts by mass of non-fluorinated rubber 1, 43 parts by mass of filler 1, 7 parts by mass of zinc oxide, 21 parts by mass of wet silica, 1.4 parts by mass of stearic acid, 3 parts by mass of anti-aging agent, 21 parts by mass of plasticizer and 3 parts by mass of peroxide were blended and kneaded at 25 to 70 ° C. using an open roll equipped with two 8-inch rolls. This was left at room temperature for about 20 hours and then kneaded again with the same open roll to produce a 1.2-mm-thick unvulcanized non-fluorinated rubber sheet.

Example 1
The 3.0-mm-thick unvulcanized fluororubber sheet produced in Production Example 1 and the 1.2-mm-thick unvulcanized non-fluororubber sheet produced in Production Example 12 were overlapped, and the width of one end was approximately After sandwiching a 10-15 mm fluororesin film (thickness 150 μm, manufactured by Daikin Industries, Ltd., trade name NEOFLON FEP NF-0150) between both sheets, a metal spacer is used so that the resulting sheet has a thickness of 2 mm. Was inserted into a metal mold and pressurized at 170 ° C. for 20 minutes to vulcanize to obtain a sheet-like laminate. The obtained laminate was cut into strips having a width of 25 mm and a length of 100 mm, and a test piece was prepared by peeling off the fluororesin film and grasping it. Using this test piece, a T peel test was performed at 23 ° C. at a peel rate of 50 mm / min, and the adhesive strength (N / cm) was measured. Moreover, the peeling mode was observed and evaluated according to the following criteria. The results are shown in Table 4.

(Peeling mode)
A: Material fracture fractured.
A: The interface between the fluororubber layer and the non-fluororubber layer was sufficiently adhered and difficult to peel.
X: Peeled at the interface between the fluororubber layer and the non-fluororubber layer.

Examples 2-10
A sheet-like laminate for a peel test was prepared in the same manner as in Example 1 except that the unvulcanized fluororubber sheet produced in each of Production Examples 2 to 10 was used as the unvulcanized fluororubber sheet. Exfoliation mode was investigated. The results are shown in Table 4.

  From the results of Table 4, it can be seen that the fluororubber layer and the non-fluororubber layer are firmly bonded.

Claims (7)

  A laminate comprising a fluororubber layer (a) containing a fluororubber (a1) and a fluororesin (a2) and a non-fluorine rubber layer (b), wherein the fluororubber (a1) contains vinylidene fluoride units. A fluororubber laminate, which is a copolymer, wherein the mass ratio (a1) / (a2) of the fluororubber (a1) to the fluororesin (a2) in the fluororubber layer (a) is 60/40 to 97/3.   The fluororesin (a2) of the fluororubber layer (a) is a tetrafluoroethylene-hexafluoropropylene copolymer, an ethylene-tetrafluoroethylene copolymer, a chlorotrifluoroethylene-tetrafluoroethylene copolymer, a tetrafluoroethylene- The laminate according to claim 1, which is a hexafluoropropylene-vinylidene fluoride copolymer or polyvinylidene fluoride.   The non-fluorinated rubber in the non-fluorinated rubber layer (b) is acrylonitrile-butadiene rubber or hydrogenated rubber thereof, blend rubber of acrylonitrile-butadiene rubber and polyvinyl chloride, epichlorohydrin rubber, ethylene-propylene rubber, chlorosulfonated polyethylene. The laminate according to claim 1 or 2, comprising rubber, silicone rubber or acrylic rubber.   Fluoro rubber layer (a) containing fluororubber (a1) and fluororesin (a2), which are copolymers containing vinylidene fluoride units, in a mass ratio (a1) / (a2) of 60/40 to 97/3 A method for producing a fluororubber laminate, comprising vulcanizing and bonding the fluororubber layer (b).   After the fluororubber composition for forming the fluororubber layer (a) kneads the fluororubber (a1) and the fluororesin (a2) above the melting point of the fluororesin (a2), the other additives for the rubber composition The production method according to claim 4, which is a vulcanizable fluororubber composition obtained by blending and kneading at a temperature lower than the vulcanization molding temperature.   The molded article formed from the laminated body in any one of Claims 1-3.   A fuel transport hose formed from the laminate according to claim 1.