Laminate, and method for manufacturing the same

Abstract

To provide a laminate which hardly peels a layer composed of a vulcanized rubber, and a layer that is laminated on the layer by being bonded to the layer by an adhesive layer, is composed of a vulcanized rubber and includes a storage body capable of storing a functional component.SOLUTION: A laminate includes a first layer and a second layer composed of a vulcanized rubber, and an adhesive layer which is disposed between the first layer and the second layer and bonds the first layer and the second layer, wherein the second layer includes a storage body capable of storing a functional component having a sensor function, the adhesive layer is formed by coating or covering an adhesive material having a glass transition temperature (Tg) of -50 to 0°C on both surfaces of a base material, and the adhesive material is brought into contact with the first layer and the second layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a laminate including a housing capable of housing a functional component having a sensor function, and a method for manufacturing the same. [Background technology]

[0002] In order to detect tire information such as air pressure, internal temperature, and wear level, functional components having a sensor function (for example, electronic components such as a sensor unit) are disposed on the inner surface of the tire. When a layer including a vulcanized rubber container capable of accommodating this functional component is laminated and attached to a layer on the inner surface of the tire (such as an inner liner layer), vulcanization bonding, as described in Patent Document 1, for example, is used. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 105511 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, when a layer including a vulcanized rubber container capable of housing functional components is laminated and attached to a layer on the tire inner surface to obtain a laminate, there are situations in which it is difficult to use vulcanization adhesion as described above, and therefore an adhesive layer such as double-sided tape is also used. However, there is room for further improvement in adhesive layers such as double-sided tape in terms of making it difficult for the laminate to peel off during running, etc., that is, to make it difficult for the layer including the attached vulcanized rubber container (the container in which the functional components are housed) to peel off from the layer on the tire inner surface.

[0005] Therefore, an object of the present invention is to provide a laminate that is difficult to peel off from a layer made of vulcanized rubber and a layer made of vulcanized rubber and including a container capable of containing functional components, which is laminated and bonded to the layer with an adhesive layer. [Means for solving the problem]

[0006] In order to solve the above problems, the present inventors conducted extensive research and found a laminate comprising a first layer and a second layer, both made of vulcanized rubber, and an adhesive layer disposed between the first and second layers and bonding the first and second layers together, wherein the second layer includes a housing capable of housing a functional component having a sensor function, and the adhesive layer is formed by applying or coating an adhesive material having a glass transition temperature (Tg) of -50 to 0°C to both sides of a substrate, and wherein the laminate in which the adhesive material is attached to the first and second layers is difficult to peel from the first layer and the second layer, thereby completing the present invention.

[0007] That is, the present invention provides the following: <1> ~ <11> This includes embodiments of the present invention. <1> A laminate comprising: a first layer and a second layer, both of which are made of vulcanized rubber; and an adhesive layer disposed between the first layer and the second layer and adhering the first layer and the second layer together; the second layer includes a housing capable of housing a functional component having a sensor function, The adhesive layer is formed by applying or coating an adhesive material having a glass transition temperature (Tg) of −50 to 0° C. on both sides of the substrate, and the adhesive material is in contact with the first layer and the second layer. Laminate. <2> The adhesive material of the adhesive layer is an acrylic adhesive material and / or a rubber adhesive material. <1> The laminate according to claim 1. <3> the adhesive material in the adhesive layer that is in contact with the first layer is a rubber-based adhesive material; <1> or <2> The laminate according to claim 1. <4> the adhesive material in the adhesive layer that is in contact with the second layer is an acrylic adhesive material; <3> The laminate according to claim 1. <5> The vulcanized rubber constituting the first layer is a butyl rubber vulcanizate or a halogenated butyl rubber vulcanizate. <1> ~ <4> 10. The laminate according to claim 9, wherein the first and second layers are laminates. <6> The vulcanized rubber constituting the second layer is at least one vulcanizate selected from the group consisting of natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene copolymer rubber, butyl rubber, halogenated butyl rubber, chloroprene rubber, and acrylonitrile-butadiene copolymer rubber. <1> ~ <5> 10. The laminate according to claim 9, wherein the first and second layers are laminates. <7> <1> ~ <6> A tire comprising, on its inner surface, the laminate according to any one of the above. <8> <1> ~ <6> A method for producing a laminate according to any one of the above, a lamination step of adhering the first layer and the second layer, in which the functional component is not housed in the housing, or the functional component is housed in the housing, with the adhesive layer to laminate them, A method for manufacturing a laminate. <9> a coating step of coating a trichloroisocyanuric acid solution on the surface of the first layer and / or the second layer to be bonded to the adhesive layer before the lamination step; <8> A method for producing the laminate described in . <10> The lamination step is a step of laminating the adhesive layer on the first layer, pressing the adhesive layer onto the first layer using a jig, and then laminating and adhering the second layer to the adhesive layer. <8> or <9> A method for producing the laminate described in . <11> the adhesive material constituting at least one surface of the adhesive layer is a rubber-based adhesive material, In the lamination step, the adhesive layer is laminated on the first layer so that the surface of the adhesive layer made of the rubber-based adhesive material is in contact with the first layer. <10> A method for producing the laminate described in . [Effects of the Invention]

[0008] According to the present invention, it is possible to obtain a laminate that is difficult to peel, which comprises a first layer made of vulcanized rubber and a second layer that is laminated and bonded to the first layer by an adhesive layer and includes a container that can house functional components, and a tire that includes this laminate on its inner surface. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a partial cross-sectional view showing an embodiment of a laminate according to the present invention. [Figure 2] 1 is a meridian cross-sectional view showing an embodiment of a tire including a laminate according to the present invention on the inner surface thereof. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will now be described. The present invention provides a laminate comprising first and second layers, both made of vulcanized rubber, and an adhesive layer disposed between the first and second layers and bonding the first and second layers together, wherein the second layer includes a housing capable of housing a functional component having a sensor function, and the adhesive layer is formed by applying or coating an adhesive material having a glass transition temperature (Tg) of −50 to 0° C. to both sides of a substrate, the adhesive material being in contact with the first and second layers. Hereinafter, this laminate will also be referred to as the “laminate of the present invention.”

[0011] In the present invention, unless otherwise specified, a numerical range expressed using "to" means a numerical range in which the numerical value before "to" is the lower limit and the numerical value after "to" is the upper limit.

[0012] The configuration and components of each layer in the laminate according to the present invention will be described in detail below with reference to the drawings. Note that the dimensional ratios (length, thickness, etc.) and orientations of each component shown in the drawings may differ from the actual dimensional ratios and orientations in order to facilitate understanding of the invention. In addition, some reference numerals may be omitted.

[0013] [1st layer] The first layer of the laminate according to the present invention is made of vulcanized rubber. That is, it is a layer made of a rubber composition made of vulcanized rubber. Therefore, this first layer contains at least vulcanized rubber (a rubber component vulcanized by adding a vulcanizing agent), and may further contain appropriate amounts of various additives commonly used in rubber compositions, such as a vulcanization accelerator, a vulcanization accelerator aid, carbon black, a white filler (silica, talc, mica, clay, calcium carbonate, titanium oxide, magnesium carbonate, etc.), a resin component (terpene resin, coumarone resin, indene resin, rosin resin, etc.), zinc oxide (zinc white), oil (process oil, etc.), stearic acid, lecithin, an antioxidant, and a plasticizer, as optional components.

[0014] Examples of vulcanized rubber that may be used for the first layer include diene rubber vulcanizates such as natural rubber (NR) vulcanizates, isoprene rubber (IR) vulcanizates, butadiene rubber (BR) vulcanizates, styrene-butadiene copolymer rubber (styrene butadiene rubber, SBR) vulcanizates, acrylonitrile-butadiene copolymer rubber (nitrile rubber, NBR) vulcanizates, chloroprene rubber (CR) vulcanizates, styrene-isoprene copolymer rubber vulcanizates, isoprene-butadiene copolymer rubber vulcanizates, and styrene-butadiene-vinylpyridine terpolymer (VP) vulcanizates; butyl rubber (IIR) vulcanizates; and halogenated butyl rubber vulcanizates.

[0015] Although sulfur is a typical example of a vulcanizing agent, compounds other than sulfur, such as peroxides, which have the function of crosslinking between polymers, may also be used. These may also be used in combination. The content of the vulcanizing agent in the first layer (the total content when two or more types are used in combination) is preferably 1 to 5 parts by mass per 100 parts by mass of the rubber component contained in the first layer.

[0016] When the laminate according to the present invention is included in the inner surface of a tire, the first layer may be a vulcanized rubber layer that forms the inner surface of the tire, for example, an inner liner layer attached to the inner surface of a tubeless tire, etc. In this case, the vulcanized rubber that forms the first layer is more preferably a butyl rubber (IIR) vulcanizate or a halogenated butyl rubber vulcanizate (including mixtures thereof), and even more preferably a halogenated butyl rubber vulcanizate (particularly a brominated butyl rubber vulcanizate).

[0017] The thickness of the first layer is not limited, but may be, for example, 0.1 to 3.0 mm, with the lower limit being 0.2 mm or more, 0.3 mm or more, or 0.5 mm or more, and the upper limit being 2.5 mm or less, 2.0 mm or less, or 1.5 mm or less. Here, the layer thickness of the first layer is the thickness of the first layer (layer length in the direction perpendicular to the surface of the first layer), and is the average value obtained by measuring at 10 arbitrary locations.

[0018] [Second layer] The second layer of the laminate according to the present invention is also made of vulcanized rubber, just like the first layer. That is, it is also a layer made of a rubber composition made of vulcanized rubber. Therefore, this second layer also contains at least vulcanized rubber, and may further contain appropriate amounts of various optional additives commonly used in rubber compositions, such as vulcanization accelerators, vulcanization accelerator assistants, carbon black, white fillers (silica, talc, mica, clay, calcium carbonate, titanium oxide, magnesium carbonate, etc.), resin components (terpene resins, coumarone resins, indene resins, rosin resins, etc.), zinc oxide (zinc white), oils (process oils, etc.), stearic acid, lecithin, antioxidants, plasticizers, etc.

[0019] The vulcanized rubber constituting the second layer may be the same as that of the first layer. However, from the viewpoint of durability of the container contained therein, the vulcanized rubber constituting the second layer (i.e., the vulcanized rubber constituting the container) is preferably at least one vulcanizate selected from the group consisting of natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene copolymer rubber (styrene-butadiene rubber, SBR), butyl rubber (IIR), halogenated butyl rubber, chloroprene rubber (CR), and acrylonitrile-butadiene copolymer rubber (nitrile rubber, NBR), and even more preferably a vulcanizate of a mixture of natural rubber (NR) or isoprene rubber (IR) and butadiene rubber (BR). The mixing ratio of this mixture of natural rubber (NR) or isoprene rubber (IR) and butadiene rubber (BR) is preferably less than 50% by mass, even more preferably 30% by mass or less, and even more preferably 20% by mass or less.

[0020] Similarly to the first layer, sulfur is a typical example of a vulcanizing agent, but compounds other than sulfur, such as peroxides, that have the ability to crosslink polymers, may also be used. These may also be used in combination. The content of the vulcanizing agent in the second layer (the total content when two or more types are used in combination) is preferably 1 to 5 parts by mass per 100 parts by mass of the rubber component contained in the second layer.

[0021] As described above, the second layer includes a housing capable of housing a functional component having a sensor function. Therefore, the housing included in the second layer is also made of the same vulcanized rubber and is integrated with the functional component. The shape of the housing is not limited as long as it can house the functional component. For example, a housing 23 having a shape such as that shown in FIG. 1 is exemplified. In the embodiment of FIG. 1, the first layer 11 and the second layer 21 including the housing 23 (with which the housing 23 is integrated) are stacked and bonded via an adhesive layer 31 to form a laminate 100. The housing portion of the housing 23 can house the functional component, with its side walls surrounding the housing. The thickness of this second layer (including the thickness of the container, the average value obtained by measuring at any 10 points in the area including the container) is not particularly limited, but may be, for example, a thickness that exceeds the thickness of the first layer to which it is adhered.

[0022] The functional component housed in this housing is not limited as long as it has a sensor function for detecting tire information and the like and has a shape that can be housed in the housing. Examples include electronic components including various sensors, transmitters, receivers, control circuits, batteries, etc. Examples of information detected and acquired by the sensor function include the internal temperature and internal pressure (air pressure) of a pneumatic tire, and the amount of wear in the tread. Temperature sensors and pressure sensors can be used to measure the internal temperature and internal pressure. A preferred example of a functional component for detecting the amount of wear in the tread is one in which a sensor element using a piezoelectric element is disposed, and the sensor element detects an output voltage corresponding to tire deformation during driving, and the amount of wear in the tread is detected based on the output voltage. In other words, a sensor function using a piezoelectric element as the sensor element is more preferable from the perspective of detecting the amount of wear in the tire tread. Alternatively, an acceleration sensor or a magnetic sensor can also be used.

[0023] [Adhesive layer] The adhesive layer of the laminate of the present invention is a layer disposed between the first and second layers and bonding them together. That is, the adhesive layer is a layer sandwiched between the first and second layers and in contact with both layers, bonding them together. The laminate of the present invention is laminated so that there is essentially no area between the first and second layers where the adhesive layer is absent. Furthermore, the adhesive layer is formed by applying or coating an adhesive material having a glass transition temperature (Tg, measured by differential scanning calorimetry (DSC)) of −50 to 0°C on both sides of the substrate, and the adhesive material (the layer of the adhesive layer made of the adhesive material) is in contact with the first and second layers (is in direct contact with them, or is in direct contact with them). Therefore, this adhesive layer has a substrate, and both the surface that comes into contact with the first layer (the surface arranged on the first layer side) and the surface that comes into contact with the second layer (the surface arranged on the second layer side) are provided with a predetermined adhesive material, that is, both surfaces of this adhesive layer are made of the predetermined adhesive material, which come into contact with the first layer or the second layer to bond the first layer and the second layer together. For example, a double-sided tape that satisfies the above configuration is shown as a preferred embodiment of this adhesive layer.

[0024] The adhesive materials coated on or on both sides of the substrate are not limited as long as they have a glass transition temperature (Tg) in the range of −50 to 0°C, but acrylic and / or rubber adhesive materials with a glass transition temperature (Tg) of −50 to 0°C are preferred. The adhesive layer may be formed by coating or covering both sides of the substrate with the same adhesive material (e.g., an acrylic adhesive material coated on or on both sides of the substrate, or a rubber adhesive material coated on or on both sides of the substrate), or by coating or covering each side with different adhesive materials (e.g., an acrylic adhesive material coated on or on one side of the substrate and a rubber adhesive material coated on or on the other side) as long as both have a glass transition temperature (Tg) in the range of −50 to 0°C. Alternatively, a mixture of different adhesive materials (mixed adhesive material) may be coated or covered on at least one side of the substrate, as long as the glass transition temperature (Tg) is −50 to 0°C. If the glass transition temperature of this adhesive material is outside the above range, peeling may easily occur at the bonding interface with the first layer or the second layer.

[0025] In particular, when the adhesive layer is pressed onto the first layer using a jig in the lamination step of the manufacturing method of the laminate according to the present invention described below, a uniform adhesion state (pressure-bonded state) is easily obtained by pressing the first layer (particularly a first layer made of vulcanized rubber or a halogenated butyl rubber vulcanizate) and the adhesive layer with the jig in this lamination step, and the adhesion is more likely to be enhanced and less likely to peel. Therefore, it is more preferable that the adhesive material in this adhesive layer that is in contact with the first layer (the adhesive material that forms the surface that is in contact with the first layer and is arranged on the first layer side; in the embodiment of Figure 1, the adhesive material that forms the layer indicated by symbol 35a) is a rubber-based adhesive material with the above-mentioned glass transition temperature.

[0026] In addition, if the adhesive material in this adhesive layer that is in contact with the first layer is a rubber-based adhesive material with the above-mentioned glass transition temperature, and the adhesive material in contact with the second layer (the adhesive material that constitutes the surface that is in contact with the second layer arranged on the second layer side, the adhesive material that constitutes the layer indicated by symbol 35b in the embodiment of Figure 1) is a rubber-based adhesive material or an acrylic adhesive material with the above-mentioned glass transition temperature, this is even more preferable from the viewpoint of uniform adhesion (improved adhesion) of the entire laminate, including the adhesion state between the adhesive layer and the second layer that is made of a vulcanizate of a mixture of natural rubber and butadiene rubber, a butyl rubber vulcanizate, a halogenated butyl rubber vulcanizate, a vulcanizate of a mixture of natural rubber and styrene-butadiene copolymer rubber, a chloroprene rubber vulcanizate, or an acrylonitrile-butadiene copolymer rubber vulcanizate. Among these, if the adhesive material in the adhesive layer that is in contact with the first layer is a rubber-based adhesive material with the above glass transition temperature, and the adhesive material that is in contact with the second layer is an acrylic-based adhesive material with the above glass transition temperature, that is, if both sides of the adhesive layer are each made of different types of adhesive materials that satisfy the above glass transition temperature, this is more preferable from the perspective of uniform adhesion (improved adhesion) of the entire laminate, including the adhesion state between the second layer and the adhesive layer, when the first layer and the second layer are made of different types of vulcanized rubber (especially when the first layer is made of butyl rubber vulcanizate or halogenated butyl rubber vulcanizate and the second layer is made of a vulcanizate of a mixture of natural rubber and butadiene rubber or a chloroprene rubber vulcanizate).

[0027] Here, "acrylic adhesive material" refers to an adhesive material whose main component is an acrylic acid ester or a methacrylic acid ester (containing more than 50% by mass), and the acrylic acid ester or methacrylic acid ester is preferably an alkyl acrylate or an alkyl methacrylate, and the number of carbon atoms in the alkyl group is preferably 1 to 3. Furthermore, "rubber adhesive material" refers to an adhesive material whose main component is a polymeric elastomer rubber (containing more than 50% by mass), and the polymeric elastomer rubber is preferably polyisoprene rubber, styrene-butadiene copolymer rubber, ethylene-propylene copolymer rubber, or the like, having a weight-average molecular weight (measured in terms of standard polystyrene by gel permeation chromatography using tetrahydrofuran as a solvent) of 50,000 to 500,000.

[0028] Furthermore, the range of the glass transition temperature (Tg) of this adhesive material is more preferably −45° C. or higher, and more preferably −30° C. or higher, on both sides of the substrate, so that the effects of the present invention are more easily exhibited. The upper limit is more preferably −5° C. or lower, and more preferably −10° C. or lower.

[0029] Furthermore, the substrate of this adhesive layer (the layer designated by the reference numeral 33 in the embodiment of FIG. 1 ) is not limited, but is preferably composed of a nonwoven fabric, polyester, or acrylic foam (acrylic foam) from the viewpoint of durability (vibration resistance, impact resistance, etc.) when the laminate of the present invention is included in the inner surface of a tire. Furthermore, this substrate may be composed of multiple layers, as long as the effects of the present invention are not affected. For example, an embodiment may include layers (substrate surface layer and substrate inner layer) composed of different materials on at least one surface of the substrate or inside the substrate. Note that a configuration without this substrate (substrate-less adhesive layer) may reduce the durability of the laminate and may also make the interfacial peeling between the first layer or second layer and the adhesive layer more likely to occur due to impact, etc.

[0030] The thickness of this adhesive layer (total layer thickness including the substrate and adhesive material) is also not limited, but when the laminate according to the present invention is included on the inner surface of a tire, it is preferably, for example, 0.1 to 2.0 mm, and the lower limit may be 0.15 mm or more. The upper limit is preferably 1.5 mm or less, more preferably 1.0 mm or less, even more preferably 0.8 mm or less, and even more preferably 0.4 mm or less. Of these, the thickness of the layers of adhesive material applied or coated on both sides may be 10 to 1000 μm in total, and more preferably 100 μm or less. Here, the layer thickness of the adhesive layer refers to the thickness of the adhesive layer (the layer length in the direction perpendicular to the surface of the adhesive layer), and is also the average value obtained by measuring at 10 random locations. The thickness of the adhesive material can be measured in the same way as the layer thickness of the adhesive layer, but it can also be calculated from the thickness of the substrate and the layer thickness of the entire adhesive layer.

[0031] [tire] As described above, the laminate according to the present invention, which includes the first layer, the second layer including the housing, and the adhesive layer bonding them together, may be included in the inner surface of a tire. In other words, a tire may include the laminate according to the present invention on its inner surface. For example, an embodiment as shown in FIG. 2 is exemplified. The tire of the embodiment shown in FIG. 2 includes a tread portion 1 extending in the tire circumferential direction and forming an annular shape, a pair of sidewall portions 2, 2 disposed on both sides (both ends in the tire width direction) of the tread portion 1, and a pair of bead portions 3, 3 disposed radially inward of the pair of sidewall portions 2. At least one carcass layer 4 is mounted between the pair of bead portions 3, 3. The carcass layer 4 includes reinforcing cords and is folded back from the inner side to the outer side of the tire around bead cores 5 disposed in each bead portion 3. A bead filler 6 made of a rubber composition having a triangular cross section is disposed on the outer periphery of the bead core 5. Meanwhile, one or more belt layers 7 are disposed on the outer periphery of the carcass layer 4 in the tread portion 1. At least one belt cover layer 8 is disposed on the outer peripheral side of the belt layer 7 for the purpose of improving high-speed durability, etc. An inner liner layer 9 (first layer 11) is disposed on the inner surface of the tire, and a member including a container (second layer 21) is disposed and laminated to the inner liner layer 9 by a predetermined adhesive layer, and these constitute the laminate 100.

[0032] The components of the tire (components constituting each member such as the tread portion and each layer such as the belt layer) are not particularly limited, and any known components for constituting a tire such as a rubber component can be used. It is more preferable that the inner liner layer has the above-mentioned configuration. Furthermore, the tire size and the tire application are not particularly limited, and various types of tires can be used, such as tires for passenger cars, trucks and buses, and off-road tires.

[0033] This tire is provided with the laminate of the present invention having the above-described configuration on the tire inner surface (the tire inner surface of the tread portion), but the position of the laminate of the present invention is not particularly limited as long as it is on the tire inner surface, and it may be a position that does not pass through the center point of the tire width direction on the tire inner surface.

[0034] The tire is preferably a pneumatic tire. The gas to be filled in the pneumatic tire may be, for example, air, nitrogen, an inert gas such as argon or helium, or other gases.

[0035] The laminate of the present invention, including the embodiments described above, is resistant to peeling between the first layer made of vulcanized rubber and the second layer made of vulcanized rubber and including a container capable of accommodating functional components, which are laminated and bonded to the first layer with an adhesive layer. Even when the laminate of the present invention is included on the inner surface of a tire and the tire is driven with functional components accommodated in the container, peeling is resistant and the tire has excellent durability.

[0036] [Manufacturing method] The method for manufacturing a laminate according to the present invention includes a lamination step of bonding the first layer and the second layer (a second layer in which a functional component is not housed in a housing or a functional component is housed in a housing) with the adhesive layer. Therefore, in this lamination step, the functional component may be housed in a housing included in the second layer before lamination and bonding. Alternatively, the second layer may be laminated and bonded before the functional component is housed in the housing. The lamination order is not limited, but it is preferable to first laminate and bond the first layer and the adhesive layer, and then laminate and bond the adhesive layer and the second layer. However, it is also acceptable to first laminate and bond the second layer and the adhesive layer, and then laminate and bond the adhesive layer and the first layer. In this lamination step, the layers are laminated so that there is substantially no area between the first and second layers where the adhesive layer is not present.

[0037] To facilitate adhesion, it is more preferable to include a coating step prior to this lamination step in which a trichloroisocyanuric acid solution is applied to the surfaces of the first and / or second layers that will be bonded to the adhesive layer. This trichloroisocyanuric acid solution may be a solution containing 1 to 10 (w / w)% trichloroisocyanuric acid in an organic solvent such as methyl ethyl ketone (MEK), with a concentration of 2 to 5 (w / w)% being more preferable. This coating step partially cleaves the polymer (vulcanized rubber) near the surfaces that will be bonded to the adhesive layer of the first and / or second layers, resulting in reaction with chlorine atoms, which further improves adhesion at the polymer ends with chlorine atoms.

[0038] Furthermore, it is more preferable that the lamination step be a step of first laminating an adhesive layer on the first layer, press-bonding the adhesive layer to the first layer using a jig, and then laminating and bonding the second layer to the adhesive layer. This is because a uniform bond (press-bonded state) can be easily achieved by these laminations and bondings (particularly, lamination and bonding between the first layer and the adhesive layer). In this case, as described above, if the adhesive material in the adhesive layer that contacts the first layer (constituting the surface that contacts the first layer, or provided on the surface that contacts the first layer) is a rubber-based adhesive material, that is, if the lamination step is a step of laminating the adhesive layer on the first layer so that the surface of the adhesive layer made of a rubber-based adhesive material with a predetermined glass transition temperature contacts the first layer, pressing the adhesive layer to the first layer using a jig, and then laminating and bonding the second layer to the adhesive layer, a uniform bond can be easily achieved by pressing the first layer (particularly, if the first layer is made of a butyl rubber vulcanizate or a halogenated butyl rubber vulcanizate) and the adhesive layer using a jig. For example, one embodiment is illustrated in which the surface of the first layer is laminated so that it is in contact with one surface of the adhesive layer (preferably a surface made of a rubber-based adhesive material), and then pressure is applied to the entire surface of the adhesive layer using a jig from the other surface side to compress the layers together. In this case, it is preferable that a release liner (such as release paper) is placed on the other surface side of the adhesive layer (the side opposite to the surface that is in contact with the first layer) so as to cover the area where the adhesive material is applied or coated. In this case, compression with the jig is performed from above the release liner, and then the release liner is peeled off to laminate and bond the second layer. Furthermore, the adhesive material that constitutes the surface of the adhesive layer that is in contact with the second layer is preferably a rubber-based adhesive material or an acrylic adhesive material, as described above.

[0039] Hereinafter, examples of the present invention will be described, but the present invention is not limited to the following examples, and various modifications are possible within the technical concept of the present invention. [Example]

[0040] (Preparation and Evaluation of Laminates) Regarding the first layer composed of vulcanized rubber shown in the upper part of Table 1 below, and the second layer including a container capable of accommodating functional parts, which is composed of vulcanized rubber shown in the lower part of the upper part of Table 1 below, after applying a 3 (w / w)% trichloroisocyanuric acid MEK solution to one surface of each, an adhesive layer (double-sided tape) with both surfaces composed of an adhesive material having a glass transition temperature (Tg) shown in the middle of the upper part of Table 1 below is used, and this adhesive layer is arranged between the surfaces of the first layer and the second layer where the above coating is performed, and the adhesive layer is laminated on the first layer. After crimping using a jig from above the release liner on the other surface side of the adhesive layer, the release liner is peeled off and the second layer is laminated and adhered to produce a laminate as shown in FIG. 1 (Examples 1 to 8 and Comparative Examples 1 to 2). Regarding the laminate of Example 3, it was laminated so that the surface composed of the rubber-based adhesive material in the adhesive layer was in contact with the first layer, and after crimping using a jig from above the release liner on the other surface side, the release liner was peeled off and the second layer was laminated and adhered.

[0041] Then, for the obtained laminates of Examples 1 to 8 and Comparative Examples 1 to 2, a T-peel test was performed and evaluated as follows.

[0042] <T-peel test> For each laminate, a T-peel adhesion test was carried out in accordance with JIS K 6854 after 24 hours at 25°C. The evaluation results were as follows: those in which the adhesive layer (double-sided tape) showed cohesive failure during peeling (no interfacial peeling between the first layer and the adhesive layer and between the second layer and the adhesive layer, and the adhesive layer that was broken on both sides remained after peeling) were designated as "CF", and those with interfacial peeling between the first layer and the adhesive layer or between the second layer and the adhesive layer, and only the adhesive layer remained on one side after peeling were designated as "AF". These results are shown in the lower part of Table 1 below.

[0043] (Manufacture and evaluation of tires) An inner liner layer made of a vulcanized rubber shown in the upper part of the upper row of Table 1 below was used as the first layer on the inner surface of the tire. A 3 (w / w) % MEK solution of trichloroisocyanuric acid was then applied to this inner surface, and an adhesive layer (double-sided tape) having both sides and made of an adhesive material having a glass transition temperature (Tg) shown in the upper row of Table 1 below was laminated so that one surface of the adhesive layer was in contact with the first layer. The adhesive layer was then pressed onto the release liner on the other surface side of the adhesive layer using a jig, and the release liner was then peeled off. A second layer made of a vulcanized rubber shown in the lower part of the upper row of Table 1 below and including a housing capable of housing functional parts was then coated on the surface with a 3 (w / w) % MEK solution of trichloroisocyanuric acid, and then laminated and adhered to the surface to produce various tires (tires with housing, Examples 1 to 8 and Comparative Examples 1 and 2) as shown in Figure 2. For the tire of Example 3, the surface of the adhesive layer made of the rubber-based adhesive material was laminated so as to be in contact with the first layer, and the other surface side was pressed against the release liner using a jig. After that, the release liner was peeled off and the second layer was laminated and adhered.

[0044] Then, for the obtained tires of Examples 1 to 8 and Comparative Examples 1 and 2, a functional part having a sensor function was housed in the housing of the second layer, and a tire running test was carried out as follows, and evaluation was carried out.

[0045] <Tire running test> Each tire was mounted on a wheel with a rim size of 21 x 9.5J, and a running test was performed using a drum testing machine (air pressure 120 kPa, 102% of the maximum load, running speed 81 km / h, running distance 10,000 km). After the running test, the condition of the laminate (particularly near the housing) was visually inspected, and the adhesive stability was evaluated according to the following criteria. The results are also shown in the lower part of Table 1 below. ◯: Almost no interfacial peeling was observed between the first and second layers. △: Some interfacial peeling was observed between the first and second layers. ×: Significant interfacial peeling was observed between the first and second layers.

[0046] [Table 1]

[0047] The details of each component, material, etc. in Table 1 above are as follows: BIIR: Brominated butyl rubber (vulcanizate) IIR: Butyl rubber (vulcanized) NR / BR: Natural rubber / butadiene rubber = 95 / 5 (mass ratio) (vulcanizate) NR / SBR: Natural rubber / styrene-butadiene copolymer rubber = 40 / 60 (mass ratio) (vulcanizate) CR: Chloroprene rubber (vulcanized) NBR: Acrylonitrile-butadiene copolymer rubber (vulcanized) Tape 1: VR5000T (manufactured by Nitto Denko Corporation; double-sided tape with a thickness of 300 μm, a nonwoven fabric base material, and rubber adhesive materials on both sides with the above Tg) Tape 2: 88308 (manufactured by Tesa Tape; double-sided tape with a thickness of 800 μm, an acrylic foam base material, and adhesive materials on both sides that are acrylic adhesive materials with the above Tg) Tape 3: VR5321 (manufactured by Nitto Denko Corporation; thickness 150 μm, base material polyester film, adhesive material on both sides is a rubber-based adhesive material with the above Tg on one side and an acrylic-based adhesive material with the above Tg on the other side) Tape 4: Beta Tape 4402 (manufactured by 3M; thickness 1000 μm, substrate-less, double-sided tape with adhesive material made of acrylic adhesive material with the above Tg) Tape 5: No. 5915 (manufactured by Nitto Denko Corporation; 50 μm thick, substrate-less, double-sided tape with an acrylic adhesive material having the above Tg)

[0048] These results showed that when first and second layers, both made of vulcanized rubber, were bonded together with adhesive layers (double-sided tape) formed by coating both sides of a substrate with a predetermined adhesive material after application of a trichloroisocyanuric acid solution, peeling at the bonding interface between the laminated first and second layers was difficult (Examples 1 to 8). In particular, Examples 1 and 3, in which the surface of the adhesive layer made of a predetermined rubber-based adhesive material was laminated onto the first layer made of brominated butyl rubber vulcanizate and then pressure-bonded using a jig, and then the second layer was laminated, were extremely preferable because peeling at the bonding interface was extremely difficult. On the other hand, when the adhesive layer was substrate-free and the glass transition temperature (Tg) of the adhesive material was low or high, peeling was likely to occur at the bonding interface of the laminated first or second layer (Comparative Examples 1-2). [Explanation of symbols]

[0049] 1 Tread section 2 Sidewall 3 Bead section 4 carcass layers 5 bead core 6 Bead filler 7 Belt Layer 8 Belt cover layer 9 Inner liner layer 11 1st layer 21 2nd layer 23 Containment Unit 31 Adhesive layer 33 Base material 100 laminate

Claims

1. A laminate comprising: a first layer and a second layer, both of which are made of vulcanized rubber; and an adhesive layer disposed between the first layer and the second layer and adhering the first layer and the second layer together, the second layer includes a housing capable of housing a functional component having a sensor function, the adhesive layer is formed by applying or coating an adhesive material having a glass transition temperature (Tg) of −50 to 0° C. on both sides of the substrate, and the adhesive material is in contact with the first layer and the second layer; Laminate.

2. The laminate according to claim 1 , wherein the adhesive material of the adhesive layer is an acrylic adhesive material and / or a rubber adhesive material.

3. The laminate according to claim 1 or 2, wherein the adhesive material in the adhesive layer that is in contact with the first layer is a rubber-based adhesive material.

4. The laminate according to claim 3 , wherein the adhesive material in the adhesive layer that is in contact with the second layer is an acrylic adhesive material.

5. 3. The laminate according to claim 1, wherein the vulcanized rubber constituting the first layer is a butyl rubber vulcanizate or a halogenated butyl rubber vulcanizate.

6. 3. The laminate according to claim 1 or 2, wherein the vulcanized rubber constituting the second layer is at least one vulcanizate selected from the group consisting of natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene copolymer rubber, butyl rubber, halogenated butyl rubber, chloroprene rubber, and acrylonitrile-butadiene copolymer rubber.

7. A tire comprising the laminate according to claim 1 or 2 on its inner surface.

8. A method for producing the laminate according to claim 1 or 2, a lamination step of adhering the first layer and the second layer, in which the functional component is not housed in the housing, or the functional component is housed in the housing, together with the adhesive layer, and laminating the first layer and the second layer, in which the functional component is housed in the housing, A method for manufacturing a laminate.

9. The method for producing a laminate according to claim 8, further comprising, before the lamination step, a coating step of applying a trichloroisocyanuric acid solution to a surface of the first layer and / or the second layer to be bonded to the adhesive layer.

10. 9. The method for manufacturing a laminate according to claim 8, wherein the lamination step is a step of laminating the adhesive layer on the first layer, pressing the adhesive layer to the first layer using a jig, and then laminating and adhering the second layer to the adhesive layer.

11. the adhesive material constituting at least one surface of the adhesive layer is a rubber-based adhesive material, 11. The method for manufacturing a laminate according to claim 10, wherein in the lamination step, the adhesive layer is laminated onto the first layer so that the surface of the adhesive layer made of the rubber-based adhesive material is in contact with the first layer.

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