Elastomer film, hot melt adhesive film, and sealing film

Abstract

An elastomer film includes an elastomer composition containing a thermoplastic elastomer (1) and a plasticizer (2) having a softening point of 25°C or higher, wherein the elastomer composition has a storage modulus of 0.10 GPa or more at 1 Hz and 25°C, and a storage modulus of 1.00 MPa or less at 1 Hz and 100°C.

Description

Elastomer Film, Hot Melt Adhesive Film, and Encapsulation Film

[0001] The present invention relates to an elastomer film, a hot melt adhesive film, and an encapsulation film.

[0002] A laminate comprising a combination of a resin layer having a storage modulus within a predetermined range and a glass substrate is known (see, for example, Patent Document 1).

[0003] International Publication No. 2023 / 176456

[0004] In the technology of Patent Document 1, when a glass substrate alone has low impact resistance, a laminate having improved impact resistance compared to the glass substrate is obtained by combining the glass substrate with a specific resin layer.

[0005] However, in the technology of Patent Document 1, when the resin layer is formed into a single film not combined with a glass substrate, the degree of stickiness on the film surface at 25° C. may be large, which may make handling of the film difficult. For example, if the degree of stickiness on the film surface at 25° C. is large, it may be difficult to adjust the position of the film on the adherend after placing the film thereon. In addition, when the film is used for hot melt adhesion, the adhesion between the film and the adherend may be insufficient, and the target object may not be well adhered.

[0006] Accordingly, there is a need for: an elastomer film that has reduced surface stickiness at 25°C and has hot melt adhesive properties capable of excellently adhering to an adherend; a hot melt adhesive film comprising the elastomer film; and an encapsulation film comprising the elastomer film.

[0007] The present inventors conducted intensive studies to solve the above problems. As a result, they have found that the above problems can be solved when the elastomer composition comprises an elastomer composition containing a predetermined plasticizer and the elastomer composition has a predetermined storage modulus, and thus completed the present invention. That is, the present invention provides the followings.

[0008] <1> An elastomer film comprising an elastomer composition containing a thermoplastic elastomer (1) and a plasticizer (2) having a softening point of 25°C or higher, wherein the elastomer composition has a storage modulus of 0.10 GPa or more at 1 Hz and 25°C, and a storage modulus of 1.00 MPa or less at 1 Hz and 100°C. <2> The elastomer film according to <1>, wherein the elastomer composition has a storage modulus of 1.0 GPa or more at 10000 Hz and 25°C. <3> The elastomer film according to <1> or <2>, wherein the ratio of the loss modulus to the storage modulus at 1 Hz and 25°C is 0.10 or more. <4> The elastomer film according to any one of <1> to <3>, wherein the thermoplastic elastomer (1) is one or more selected from the group consisting of aromatic vinyl compound-conjugated diene block copolymer, aromatic vinyl compound-conjugated diene block copolymer modified by a silicon atom-containing polar group, hydrogenated aromatic vinyl compound-conjugated diene block copolymer, and hydrogenated aromatic vinyl compound-conjugated diene block copolymer modified by a silicon atom-containing polar group. <5> The elastomer film according to any one of <1> to <4>, wherein the content of the plasticizer (2) in the elastomer composition is 20% by weight or more and 50% by weight or less based on 100% by weight of the elastomer composition. <6> The elastomer film according to any one of <1> to <5>, wherein the plasticizer (2) is one or more selected from the group consisting of petroleum resin and petroleum resin hydride. <7> The elastomer film according to any one of <1> to <6>, wherein the plasticizer (2) is one or more selected from the group consisting of C5 petroleum resin, C9 petroleum resin hydride, C5 / C9 petroleum resin, and C5 / C9 petroleum resin hydride. <8> The elastomer film according to any one of <1> to <7>, wherein the elastomer composition further contains moisture-absorbing particles. <9> A hot-melt adhesive film comprising the elastomer film according to any one of <1> to <8>. <10> A sealing film comprising the elastomer film according to any one of <1> to <8>.

[0009] According to the present invention, it is possible to provide an elastomer film having reduced surface stickiness at 25°C and hot-melt adhesive properties that allow for good adhesion to the object to be bonded; a hot-melt adhesive film containing the elastomer film; and a sealing film containing the elastomer film.

[0010] The present invention will be described in detail below with reference to embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and can be modified and implemented as appropriate without departing from the scope of the claims and equivalents of the present invention. The components of the embodiments shown below can be combined as appropriate. For example, any numerical value selected from the group of numerical values ​​listed as lower limits and any numerical value selected from the group of numerical values ​​listed as upper limits can be combined as appropriate.

[0011] The phrase "contains" an object encompasses both cases: the object in question alone, and the object in question plus any other object.

[0012] In the following description, "long film" refers to a film having a length of five times or more its width, preferably 10 times or more its width, and specifically a film of a length that can be wound into a roll for storage or transport. There is no particular upper limit to the length of the film; for example, it may be 100,000 times or less its width.

[0013] A structural unit formed by polymerizing a monomer is called a "monomer unit," with "unit" added after the name of the monomer. For example, a structural unit formed by polymerizing aromatic vinyl compounds as monomers is also called an "aromatic vinyl compound unit." However, the term "monomer unit" is not limited to its formation method. Typically, monomer units are repeating units.

[0014] In the following description, the directions of the elements are defined as "parallel," "perpendicular," and "orthogonal" unless otherwise specified, and may include errors within a range that does not impair the effects of the present invention, for example, within a range of ±3°, ±2°, or ±1°.

[0015] <1. Elastomer Film> <1.1. Overview of Elastomer Film> An elastomer film according to one embodiment of the present invention is an elastomer film comprising an elastomer composition containing a thermoplastic elastomer (1) and a plasticizer (2) having a softening point of 25°C or higher. Hereinafter, the elastomer composition according to this embodiment, which contains the thermoplastic elastomer (1) and the plasticizer (2), will also be referred to as elastomer composition (3). The elastomer composition (3) has a storage modulus of 0.10 GPa or higher at 1 Hz and 25°C, and a storage modulus of 1.00 MPa or lower at 1 Hz and 100°C. The elastomer film of this embodiment is easy to handle because, at 25°C, surface stickiness is reduced and the film maintains its shape. Furthermore, it softens upon heating, adheres closely to the object to be bonded, and can bond the object well. The property of being able to fix and bond an object by softening upon heating and solidifying upon cooling is called hot melt adhesion. Since stickiness is reduced at 25°C, it is easy to adjust the position of the elastomer film on the object to be bonded, even after it has been placed on the object. Therefore, the elastomer film can be softened by heating at the desired position on the object to be bonded, adhere well to the object, and bond the object.

[0016] <1.2. Elastomer Composition (3)> The elastomer film contains the elastomer composition (3) and is formed from the elastomer composition (3). Preferably, the elastomer film contains only the elastomer composition (3). Preferably, the elastomer film is a single-layer film containing only the elastomer composition (3).

[0017] (Physical properties of elastomer composition (3): Storage modulus at 1 Hz and 25°C) The storage modulus of elastomer composition (3) at 1 Hz and 25°C is usually 0.10 GPa or higher, preferably 0.15 GPa or higher, more preferably 0.20 GPa or higher, from the viewpoint of the elastomer film maintaining its shape at 25°C and reducing surface stickiness of the elastomer film at 25°C, and preferably 1.00 GPa or lower, more preferably 0.90 GPa or lower, and even more preferably 0.80 GPa or lower, from the viewpoint of improving the flexibility of the elastomer film.

[0018] The storage modulus of the elastomer composition (3) at 1 Hz and 25°C can be adjusted, for example, by changing the softening point of the plasticizer (2), adjusting the content of the thermoplastic elastomer (1), or a combination thereof. For example, increasing the softening point of the plasticizer (2) tends to increase the storage modulus. Adding a filler to the elastomer composition (3) and lowering the content of the thermoplastic elastomer (1) also tends to increase the storage modulus.

[0019] (Physical properties of elastomer composition (3): Storage modulus at 1 Hz and 100°C) The storage modulus of elastomer composition (3) at 1 Hz and 100°C is usually 1.00 MPa or less, preferably 0.90 MPa or less, and more preferably 0.80 MPa or less, from the viewpoint of improving the adhesion of elastomer composition (3) to the object to be bonded and thus improving hot melt adhesion. The lower limit is not particularly limited, but is usually greater than 0.00 MPa, for example, 0.01 MPa or more.

[0020] The storage modulus of the elastomer composition (3) at 1 Hz and 100°C can be adjusted, for example, by adjusting the content of the plasticizer (2), changing the softening point of the plasticizer (2), adjusting the content of the thermoplastic elastomer (1), or a combination thereof. For example, as the content of the plasticizer (2) increases, the storage modulus tends to decrease. As the softening point of the plasticizer (2) decreases, the storage modulus tends to decrease. When the content of the thermoplastic elastomer (1) is reduced by adding a filler to the elastomer composition (3), the storage modulus tends to increase.

[0021] (Physical properties of elastomer composition (3): Storage modulus at 10,000 Hz and 25°C) From the viewpoint of improving the impact resistance of the elastomer film, the storage modulus of elastomer composition (3) at 10,000 Hz and 25°C is preferably 1.0 GPa or more, more preferably 1.2 GPa or more, and even more preferably 1.3 GPa or more, and from the viewpoint of improving the flexibility of the elastomer film, it is preferably 3.0 GPa or less, more preferably 2.9 GPa or less, even more preferably 2.5 GPa or less, and even more preferably 2.4 GPa or less.

[0022] The elastomer composition (3) has a storage modulus of elasticity of preferably 1.0 GPa or more at 25°C at 10,000 Hz. Therefore, when an elastomer film containing the elastomer composition (3) is strained about 10,000 times per second, that is, about once every 1 / 10,000 second, the elastomer film does not easily deform elastically and behaves as a hard film. Therefore, against impacts equivalent to straining about once every 1 / 10,000 second, the elastomer film behaves as a hard film. In other words, if the storage modulus of elasticity at 25°C at 10,000 Hz is above the lower limit, the impact resistance of the elastomer film can be improved.

[0023] The storage modulus of the elastomer composition (3) at 10,000 Hz and 25°C can be adjusted, for example, by adjusting the content of the plasticizer (2), changing the softening point of the plasticizer (2), adjusting the content of the thermoplastic elastomer (1), or by a combination thereof. For example, increasing the content of the plasticizer (2) tends to increase the storage modulus. Raising the softening point of the plasticizer (2) also tends to increase the storage modulus. Adding a filler to the elastomer composition (3) and lowering the content of the thermoplastic elastomer (1) tends to increase the storage modulus.

[0024] (Physical properties of elastomer composition (3): Ratio of loss modulus to storage modulus at 1 Hz and 25°C) The ratio of the loss modulus to the storage modulus (loss modulus / storage modulus, loss tangent tanδ) at 1 Hz and 25°C of elastomer composition (3) is preferably 0.10 or higher, more preferably 0.12 or higher, and even more preferably 0.13 or higher, from the viewpoint of improving the impact resistance of the elastomer film, and preferably 0.50 or lower, more preferably 0.40 or lower, and even more preferably 0.30 or lower, from the viewpoint of eliminating local deformation (dents) of the elastomer film that may occur due to localized pressure. Hereinafter, the ratio of the loss modulus to the storage modulus (loss modulus / storage modulus) at 1 Hz and 25°C will also be referred to as tanδ(1 Hz, 25°C).

[0025] If tanδ (1 Hz, 25°C) is above the lower limit, a large proportion of the impact energy is lost as heat when an impact is applied to the elastomer composition (3) without being stored. Therefore, the impact resistance of the elastomer composition (3) can be improved.

[0026] tanδ (1 Hz, 25°C) can be adjusted, for example, by adjusting the ratio of plasticizer (2) to thermoplastic elastomer (1) (plasticizer (2) / thermoplastic elastomer (1)), changing the softening point of plasticizer (2), adjusting the content of thermoplastic elastomer (1), or by a combination of these. For example, increasing the ratio (plasticizer (2) / thermoplastic elastomer (1)) tends to increase tanδ (1 Hz, 25°C). Raising the softening point of plasticizer (2) tends to decrease tanδ (1 Hz, 25°C). Adding fillers to the elastomer composition (3) and lowering the content of thermoplastic elastomer (1) tends to increase tanδ (1 Hz, 25°C).

[0027] (Storage modulus and loss modulus of elastomer composition (3)) The storage modulus and loss modulus of elastomer composition (3) can be measured by the following method. The storage modulus of elastomer composition (3) at 25°C and frequencies of 10,000 Hz and 1 Hz can be determined by creating a master curve at a reference temperature of 25°C based on temperature characteristic data of the storage modulus at multiple frequencies measured by a dynamic viscoelasticity measuring device, and reading the values ​​of the storage modulus at frequencies of 10,000 Hz and 1 Hz from the master curve. The master curve is created by converting the temperature-dependent data of the storage modulus into frequency-dependent data using the WLF (Williams, Randell, Ferry) law.

[0028] The loss modulus of the elastomer composition (3) at a frequency of 1 Hz and 25°C can be determined by creating a master curve at a reference temperature of 25°C based on temperature characteristic data of the loss modulus at multiple frequencies measured by a dynamic viscoelasticity measuring device, and then reading the value of the loss modulus at a frequency of 1 Hz from the master curve.

[0029] From the obtained values ​​of the loss modulus and storage modulus at 1 Hz and 25°C, tanδ(1 Hz, 25°C) can be determined.

[0030] The storage modulus of the elastomer composition (3) at a frequency of 1 Hz and 100°C can be determined by reading the value of the storage modulus at 100°C from the storage modulus graph measured by a dynamic viscoelasticity measuring device at a measurement frequency of 1 Hz and a measurement temperature range of -120°C to 100°C.

[0031] The measurement conditions for dynamic viscoelasticity measurement may be as follows: A rectangular test specimen, 200 μm thick, 8 mm wide, and 40 mm long, formed from the elastomer composition (3), is used as the test specimen. The heating rate may be 4°C / min. The strain may be 0.05%. The measurement temperature range may be -120°C to 100°C. The measurement frequency may be 1 Hz, 5 Hz, and 10 Hz. As the measuring device, for example, a dynamic viscoelasticity measuring device "DMA850" manufactured by TA Instruments Corporation may be used.

[0032] <1.3. Thermoplastic Elastomers (1)> Thermoplastic elastomers are materials that exhibit rubber-like properties at room temperature and become plasticized at high temperatures, allowing for molding. Such thermoplastic elastomers are characterized by their tendency to stretch easily under small loads while being resistant to fracture. Specifically, at 25°C, thermoplastic elastomers exhibit a storage modulus of 0.001 to 2 GPa and a tensile elongation (elongation at break) of 100 to 2000%. Thermoplastic elastomers also soften in a high temperature range of 40°C to 200°C, where the storage modulus decreases rapidly, and the loss tangent tanδ (loss modulus / storage modulus) peaks or exceeds 1. Tensile elongation can be measured according to JIS K7113. Storage modulus and loss tangent tanδ can be measured using commercially available dynamic viscoelasticity measuring devices.

[0033] The thermoplastic elastomer (1) may be a homopolymer, a copolymer, or a mixture (polymer blend) of a homopolymer or copolymer.

[0034] Examples of thermoplastic elastomers (1) include amide-based thermoplastic elastomers; ester-based thermoplastic elastomers; olefin-based thermoplastic elastomers; aromatic vinyl compound-conjugated diene-based thermoplastic elastomers (e.g., styrene-based thermoplastic elastomers); urethane-based thermoplastic elastomers; and thermoplastic rubber crosslinked materials. Thermoplastic elastomers (1) may be used individually or in combination of two or more types in any ratio.

[0035] As the thermoplastic elastomer (1), an aromatic vinyl compound-conjugated diene thermoplastic elastomer is preferred. An aromatic vinyl compound-conjugated diene thermoplastic elastomer means a block copolymer having a polymer block (A) mainly composed of aromatic vinyl compound units and a polymer block (B) mainly composed of chain-like conjugated diene compound units; a hydride of the block copolymer; a modified product of the block copolymer or the hydride of the block copolymer; and combinations thereof. An example of a modified product is a product obtained by modifying the block copolymer or the hydride of the block copolymer with a modifying component such as an alkoxysilane, a carboxylic acid, or a carboxylic acid anhydride. Hereinafter, the block copolymer having the polymer block (A) and the polymer block (B) will also be called a specific block copolymer. Furthermore, the specific block copolymer and the hydride of the specific block copolymer together will also be called a specific block copolymer, etc.

[0036] The aforementioned specific block copolymer, which has a polymer block (A) mainly composed of aromatic vinyl compound units and a polymer block (B) mainly composed of chain-like conjugated diene compound units, is also called an aromatic vinyl compound-conjugated diene block copolymer, and the hydride of the specific block copolymer is also called a hydrogenated aromatic vinyl compound-conjugated diene block copolymer.

[0037] Furthermore, an aromatic vinyl compound unit refers to a structural unit having a structure formed by polymerizing aromatic vinyl compounds. In addition, a chain-like conjugated diene compound unit refers to a structural unit having a structure formed by polymerizing chain-like conjugated diene compounds. Chain-like conjugated diene compounds may be linear or branched. In a given polymer block, the main component unit means a unit that makes up 50% by weight or more of the polymer block, with the polymer block being 100% by weight.

[0038] Examples of aromatic vinyl compounds corresponding to aromatic vinyl compound units include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-diisopropylstyrene, 2,4-dimethylstyrene, 4-t-butylstyrene, 5-t-butyl-2-methylstyrene, 4-monochlorostyrene, dichlorostyrene, 4-monofluorostyrene, and 4-phenylstyrene. These may be used individually or in combination of two or more in any ratio. Among these, those that do not contain polar groups are preferred in terms of hygroscopicity. Furthermore, styrene is particularly preferred from the viewpoint of industrial availability and impact resistance.

[0039] The content of aromatic vinyl compound units in polymer block (A) is preferably 90% by weight or more, more preferably 95% by weight or more, particularly preferably 99% by weight or more, and is usually 100% by weight or less, and may be 100% by weight. By increasing the amount of aromatic vinyl compound units in polymer block (A) as described above, the heat resistance of thermoplastic elastomer (1) can be improved.

[0040] The polymer block (A) may contain any structural units other than aromatic vinyl compound units. Examples of arbitrary structural units include chain-like conjugated diene compound units and structural units having a structure formed by polymerizing vinyl compounds other than aromatic vinyl compounds.

[0041] Examples of the linear conjugated diene compound corresponding to the linear conjugated diene compound unit include the same examples as those given below as examples of the linear conjugated diene compound corresponding to the linear conjugated diene compound unit contained in the polymer block (B). Further, one type of the linear conjugated diene compound may be used alone, or two or more types may be used in combination at any ratio.

[0042] Examples of vinyl compounds other than aromatic vinyl compounds include linear vinyl compounds; cyclic vinyl compounds; vinyl compounds having a nitrile group, an alkoxycarbonyl group, a hydroxycarbonyl group, or a halogen group; unsaturated cyclic acid anhydrides; unsaturated imide compounds, and the like. Among these, vinyl compounds containing no polar group, such as linear olefins including ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 1-eicosene, 4-methyl-1-pentene, 4,6-dimethyl-1-heptene and the like; cyclic olefins including vinylcyclohexane and the like; are preferable from the viewpoint of hygroscopicity. Among these, linear olefins are more preferable, and ethylene and propylene are particularly preferable. Further, one of these compounds may be used alone, or two or more of them may be used in combination at any ratio.

[0043] The content of any optional structural unit in the polymer block (A) is preferably 10% by weight or less, more preferably 5% by weight or less, particularly preferably 1% by weight or less, and is usually 0% by weight or more, and may be 0% by weight.

[0044] The number of polymer blocks (A) per molecule of the specific block copolymer is preferably 2 or more, preferably 5 or less, more preferably 4 or less, and particularly preferably 3 or less. A plurality of polymer blocks (A) in one molecule may be the same as or different from each other.

[0045] The polymer block (B) included in the specific block copolymer has a linear conjugated diene compound unit. Examples of the linear conjugated diene compound corresponding to the linear conjugated diene compound unit included in this polymer block (B) include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 1,3-pentadiene. One of these may be used alone, or two or more of these may be used in combination at any ratio. Among these, those containing no polar group are preferable in terms of hygroscopicity, and 1,3-butadiene and isoprene are particularly preferable.

[0046] The content of linear conjugated diene compound units in the polymer block (B) is preferably 90% by weight or more, more preferably 95% by weight or more, particularly preferably 99% by weight or more, and is usually 100% by weight or less, and may be 100% by weight. By increasing the amount of linear conjugated diene compound units in the polymer block (B) as described above, the impact resistance of the thermoplastic elastomer at low temperatures can be improved.

[0047] The polymer block (B) may contain any structural unit other than the linear conjugated diene compound unit. Examples of the optional structural unit include an aromatic vinyl compound unit, and a structural unit having a structure formed by polymerizing a vinyl compound other than an aromatic vinyl compound. Examples of these aromatic vinyl compound units and structural units having a structure formed by polymerizing a vinyl compound other than an aromatic vinyl compound include the units exemplified as those that may be contained in the polymer block (A).

[0048] The content of any structural unit in the polymer block (B) is preferably 10% by weight or less, more preferably 5% by weight or less, particularly preferably 1% by weight or less, and is usually 0% by weight or more, and may be 0% by weight. In particular, by reducing the content of aromatic vinyl compound units in the polymer block (B), the flexibility of the thermoplastic elastomer (1) at low temperatures can be improved, and the impact resistance of the thermoplastic elastomer (1) at low temperatures can be improved.

[0049] The number of polymer blocks (B) in one molecule of a specific block copolymer is usually one or more, and may be one or two or more. There is no particular upper limit, but for example, it is three or less. When the number of polymer blocks (B) in a specific block copolymer is two or more, the polymer blocks (B) may be the same or different from each other.

[0050] The block form of the specific block copolymer may be a chain-type block or a radial-type block. Among these, the chain-type block is preferred because it has excellent mechanical strength. When the specific block copolymer has a chain-type block form, it is preferable that both ends are polymer blocks (A) because this can reduce the stickiness of the elastomer film at 25°C.

[0051] Particularly preferred block configurations for a specific block copolymer are a triblock copolymer in which polymer block (A) is bonded to both ends of polymer block (B), as represented by (A)-(B)-(A); and a pentablock copolymer in which polymer block (B) is bonded to both ends of polymer block (A), and polymer block (A) is further bonded to the other ends of both polymer block (B), as represented by (A)-(B)-(A)-(B)-(A). In particular, the (A)-(B)-(A) triblock copolymer is particularly preferred because it is easy to manufacture and allows physical properties such as viscosity to be within a desired range.

[0052] In a specific block copolymer, the ratio (wA / wB) of the weight fraction wA of total polymer block (A) in the entire specific block copolymer to the weight fraction wB of total polymer block (B) in the entire specific block copolymer is preferably 30 / 70 or more, more preferably 40 / 60 or more, even more preferably 45 / 55 or more, preferably 80 / 20 or less, more preferably 70 / 30 or less, and even more preferably 55 / 45 or less. By setting the ratio wA / wB to be above the lower limit of the above range, the heat resistance of the thermoplastic elastomer (1) can be improved. Furthermore, by setting it to be below the upper limit, the flexibility of the thermoplastic elastomer (1) can be increased, thereby improving the adhesion of the elastomer film to the object to be bonded or sealed.

[0053] The weight-average molecular weight (Mw) of the specified block copolymer is preferably 30,000 or more, more preferably 40,000 or more, particularly preferably 44,000 or more, preferably 200,000 or less, more preferably 150,000 or less, and particularly preferably 100,000 or less. The molecular weight distribution (Mw / Mn) of the specified block copolymer is preferably 3 or less, more preferably 2 or less, particularly preferably 1.5 or less, and preferably 1.0 or more. Here, Mn represents the number-average molecular weight. The weight-average molecular weight and molecular weight distribution of the specified block copolymer can be measured as polystyrene equivalent values ​​by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as the solvent.

[0054] The hydride of the specific block copolymer is obtained by hydrogenating the unsaturated bonds of the specific block copolymer described above. Here, the unsaturated bonds of the block copolymer include both aromatic and non-aromatic carbon-carbon unsaturated bonds of the main chain and side chains of the block copolymer. The hydrogenation rate is preferably 90% or more, more preferably 97% or more, and particularly preferably 99% or more of the total unsaturated bonds of the block copolymer. The higher the hydrogenation rate, the better the heat resistance and light resistance of the thermoplastic elastomer (1). Here, the hydrogenation rate of the hydride is １ This can be determined by measurement using H-NMR.

[0055] In particular, the hydrogenation rate of the non-aromatic unsaturated bonds is preferably 95% or more, more preferably 99% or more. By increasing the hydrogenation rate of the non-aromatic carbon-carbon unsaturated bonds, the light resistance and oxidation resistance of the thermoplastic elastomer (1) can be further improved.

[0056] Furthermore, the hydrogenation rate of the aromatic carbon-carbon unsaturated bond is preferably 90% or higher, more preferably 93% or higher, and particularly preferably 95% or higher. By increasing the hydrogenation rate of the carbon-carbon unsaturated bond of the aromatic ring, the glass transition temperature of the polymer block obtained by hydrogenating polymer block (A) is increased, thereby effectively improving the heat resistance of thermoplastic elastomer (1). In addition, by lowering the photoelastic coefficient of thermoplastic elastomer (1), the occurrence of unintended retardation during sealing when the elastomer film is used as a sealing film can be suppressed.

[0057] The weight-average molecular weight (Mw) of the hydride of the specific block copolymer is preferably 30,000 or more, more preferably 40,000 or more, particularly preferably 45,000 or more, preferably 200,000 or less, more preferably 150,000 or less, and particularly preferably 100,000 or less. The molecular weight distribution (Mw / Mn) of the hydride of the specific block copolymer is preferably 3 or less, more preferably 2 or less, particularly preferably 1.5 or less, and preferably 1.0 or more. By keeping the weight-average molecular weight Mw and molecular weight distribution Mw / Mn of the hydride of the specific block copolymer within the above ranges, the mechanical strength and heat resistance of the thermoplastic elastomer (1) can be improved. The weight-average molecular weight and molecular weight distribution of the hydride of the block copolymer can be measured in polystyrene equivalent values ​​by gel permeation chromatography using tetrahydrofuran as the solvent.

[0058] In the hydrogenated product of a specific block copolymer, the ratio (wA / wB) of the weight fraction wA of the total polymer block (A) to the weight fraction wB of the total polymer block (B) to the total polymer block is usually the same as the ratio wA / wB in the specific block copolymer before hydrogenation.

[0059] Specific examples of modified products of specific block copolymers or hydrides of specific block copolymers include those modified with silicon atom-containing polar groups. An example of a silicon atom-containing polar group is an alkoxysilyl group. Modified products with alkoxysilyl groups are obtained by bonding alkoxysilyl groups to the specific block copolymer or its hydride. In this case, the alkoxysilyl group may be directly bonded to the specific block copolymer or its hydride, or it may be bonded via a divalent organic group such as an alkylene group.

[0060] An example of a method for bonding an alkoxysilyl group to a specific block copolymer or its hydride is to react the specific block copolymer or its hydride with an ethylenically unsaturated silane compound in the presence of a peroxide.

[0061] As ethylenically unsaturated silane compounds, those that can be graft polymerized with specific block copolymers and that can introduce alkoxysilyl groups into specific block copolymers can be used. Examples of such ethylenically unsaturated silane compounds include vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, dimethoxymethylvinylsilane, diethoxymethylvinylsilane, p-styryltrimethoxysilane, p-styryltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acryloxypropyltriethoxysilane, and 2-norbornene-5-yltrimethoxysilane. Among these, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, dimethoxymethylvinylsilane, diethoxymethylvinylsilane, and p-styryltrimethoxysilane are preferred. Furthermore, the ethylenically unsaturated silane compound may be used alone or in combination of two or more types in any ratio.

[0062] The amount of ethylenically unsaturated silane compound is preferably 0.1 parts by weight or more, more preferably 0.2 parts by weight or more, particularly preferably 0.3 parts by weight or more, preferably 10 parts by weight or less, more preferably 5 parts by weight or less, and particularly preferably 3 parts by weight or less, based on 100 parts by weight of the specific block copolymer etc. before the introduction of the alkoxysilyl group.

[0063] As peroxides, for example, those described in International Publication No. 2016 / 153030 can be used.

[0064] Among aromatic vinyl compound-conjugated diene-based thermoplastic elastomers, one or more thermoplastic elastomers (1) are preferred from the group consisting of aromatic vinyl compound-conjugated diene block copolymer; aromatic vinyl compound-conjugated diene block copolymer modified by silicon atom-containing polar groups; hydrogenated aromatic vinyl compound-conjugated diene block copolymer; and hydrogenated aromatic vinyl compound-conjugated diene block copolymer modified by silicon atom-containing polar groups. In one embodiment, from the viewpoint of improving the heat resistance and light resistance of the elastomer film, one or more thermoplastic elastomers (1) are preferred from the group consisting of hydrogenated aromatic vinyl compound-conjugated diene block copolymer and hydrogenated aromatic vinyl compound-conjugated diene block copolymer modified by silicon atom-containing polar groups. In another embodiment, the thermoplastic elastomer (1) is preferably one or more selected from the group consisting of aromatic vinyl compound-conjugated diene block copolymers modified with silicon atom-containing polar groups and hydrogenated aromatic vinyl compound-conjugated diene block copolymers modified with silicon atom-containing polar groups, from the viewpoint of improving the adhesion between the elastomer film and the object to be sealed or bonded.

[0065] These block copolymers can have their storage modulus at 25°C adjusted by changing the weight ratio of polymer block (A) and polymer block (B) contained within them.

[0066] The glass transition temperature of the thermoplastic elastomer (1) is not particularly limited, but is preferably 40°C or higher, more preferably 70°C or higher, preferably 200°C or lower, more preferably 180°C or lower, and even more preferably 160°C or lower. The glass transition temperature can be measured from the peak of the loss tangent tanδ (loss modulus / storage modulus) measured using a dynamic viscoelasticity measuring device.

[0067] The content of thermoplastic elastomer (1) in the elastomer composition (3) is preferably 20% by weight or more, more preferably 30% by weight or more, even more preferably 35% by weight or more, preferably 90% by weight or less, more preferably 85% by weight or less, and even more preferably 80% by weight or less, based on 100% by weight of the elastomer composition (3). If the content of thermoplastic elastomer (1) in the elastomer composition (3) is above the lower limit, the stickiness of the surface of the elastomer film at 25°C can be effectively reduced. If it is below the upper limit, the hot melt adhesion of the elastomer film can be effectively improved.

[0068] <1.4. Plasticizer (2)> A plasticizer is a substance that increases the plasticity of a composition containing a polymer. Generally, a plasticizer can lower the temperature at which a composition containing a polymer can undergo plastic deformation. The softening point of the plasticizer (2) contained in the elastomer composition (3) according to this embodiment is usually 25°C or higher, preferably 40°C or higher, more preferably 50°C or higher, and even more preferably 60°C or higher, from the viewpoint of suppressing the stickiness of the elastomer film at 25°C. From the viewpoint of lowering the softening point of the elastomer composition (3) and improving hot-melt adhesion, it is preferably 135°C or lower, more preferably 125°C or lower, even more preferably 115°C or lower, even more preferably 105°C or lower, even more preferably 100°C or lower, and even more preferably 95°C or lower. The plasticizer (2) may be used alone or in any combination of two or more in any ratio. The softening point of the plasticizer (2) can be measured by the ring-sphere method in accordance with JIS K2207.

[0069] Examples of plasticizers include rosin-based resins, terpene-based resins, and petroleum-based resins. Among the plasticizers (2) contained in the elastomer composition (3), petroleum-based resins with a softening point of 25°C or higher are preferred. Petroleum-based resins refer to petroleum resins and their hydrides obtained by polymerizing fractions produced by naphtha cracking.

[0070] Petroleum-based resins typically have low polarity. Therefore, they generally have good compatibility with thermoplastic elastomers (1), and can keep the haze of the elastomer film low. In addition, because they contain few highly polar impurities, the degradation of any component in contact with the elastomer film due to highly polar impurities can be reduced.

[0071] Examples of commercially available plasticizers (2) that are petroleum-based resins include Alcon® P-90 (softening point: 90°C), Alcon P-100 (softening point: 100°C), Alcon P-115 (softening point: 115°C), Alcon M-90 (softening point: 90°C), Alcon M-100 (softening point: 100°C), Alcon M-115 (softening point: 115°C) manufactured by Arakawa Chemical Co., Ltd.; iMarb® S-100 (softening point: 100°C), iMarb S-110 (softening point 110°C), iMarb P-100 (softening point 100°C); Quinton® (registered trademark) B170 (softening point: 70°C), Quinton N180 (softening point: 80°C), Quinton R100 (softening point: 96°C), Quinton U185 (softening point: 86°C), Quinton U190 (softening point: 90°C), Quinton S195 (softening point: 94°C), Quinton DX395 (softening point: 94°C), Quinton DX390 N (softening point: 93°C), Quinton D100 (softening point: 99°C), Quinton E200SN (softening point: 102°C), Quinton D200 (softening point: 102°C), Quinton D295 (softening point: 94°C), Quinton G100B (softening point: 100°C), Quinton G115 (softening point: 115°C); Tosoh Corporation's product names Petrotac (registered trademark) 60 (softening point: 72°C), Petrotac 70 (softening point: 70°C), Petrotac 90 (softening point: Examples include Easttack® C100W (softening point 100°C), Easttack® C115W (softening point 115°C), etc., manufactured by Eastman Chemical Company.

[0072] Examples of petroleum resins include C5 petroleum resins, C5 petroleum resin hydrides, C9 petroleum resins, C9 petroleum resin hydrides, C5 / C9 petroleum resins, and C5 / C9 petroleum resin hydrides. The plasticizer (2) is preferably one or more selected from the group consisting of C5 petroleum resins, C5 petroleum resin hydrides, C9 petroleum resins, C9 petroleum resin hydrides, C5 / C9 petroleum resins, and C5 / C9 petroleum resin hydrides; more preferably one or more selected from the group consisting of C5 petroleum resins, C9 petroleum resin hydrides, C5 / C9 petroleum resins, and C5 / C9 petroleum resin hydrides; and even more preferably one or more selected from the group consisting of C5 petroleum resins, C9 petroleum resin hydrides, and C5 / C9 petroleum resins.

[0073] C9 petroleum resin refers to a resin obtained by polymerizing the C9 fraction produced by naphtha cracking or components separated from the C9 fraction. Cationic polymerization is preferred as the polymerization method. The C9 fraction is a fraction mainly containing hydrocarbons with 9 carbon atoms, and includes aromatic hydrocarbons such as styrene, vinyltoluene, α-methylstyrene, and indenes. C9 petroleum resin hydride is a resin obtained by hydrogenating C9 petroleum resin, and all of the unsaturated bonds contained in the C9 petroleum resin may be hydrogenated, or only a portion may be hydrogenated.

[0074] Examples of plasticizers (2) that are C9-type petroleum resins include Tosoh Corporation's product names Petocol LX (softening point: 98°C), Petocol 120 (softening point: 120°C), and Petocol 130 (softening point: 125°C).

[0075] Examples of plasticizers (2) that are C9-type petroleum resin hydrides include Alcon (registered trademark) P-90 (softening point: 90°C), Alcon P-100 (softening point: 100°C), Alcon P-115 (softening point: 115°C), Alcon M-90 (softening point: 90°C), Alcon M-100 (softening point: 100°C), and Alcon M-115 (softening point: 115°C), all manufactured by Arakawa Chemical Co., Ltd.

[0076] C5 petroleum resin refers to a resin obtained by polymerizing the C5 fraction produced by naphtha cracking or components separated from the C5 fraction. Cationic polymerization is preferred as the polymerization method. The C5 fraction is a fraction mainly containing hydrocarbons having 5 carbon atoms, and includes, for example, linear or cyclic aliphatic hydrocarbons such as isoprene, 1,3-pentadiene, piperylene, cyclopentadiene, and pentene. C5 petroleum resin hydride is a resin obtained by hydrogenating C5 petroleum resin, and all of the unsaturated bonds contained in the C5 petroleum resin may be hydrogenated, or only a portion may be hydrogenated.

[0077] Examples of commercially available plasticizers (2) that are C5-type petroleum resins include Quinton B170 (softening point: 70°C) and Quinton R100 (softening point: 96°C), both manufactured by Nippon Zeon Co., Ltd.

[0078] Specific examples of plasticizers (2) that are C5-type petroleum resin hydrides include Eastman Chemical Company's products Easttack C100W (softening point 100°C) and Easttack C115W (softening point 115°C).

[0079] C5 / C9 petroleum resin refers to a resin obtained by copolymerizing the C5 fraction and C9 fraction mentioned above. Cationic polymerization is preferred as the polymerization method. C5 / C9 petroleum resin hydride is a resin obtained by hydrogenating a C5 / C9 petroleum resin, and all of the unsaturated bonds contained in the C5 / C9 petroleum resin may be hydrogenated, or only a portion of them may be hydrogenated.

[0080] Specific examples of plasticizers (2) that are C5 / C9 petroleum resins include the following products manufactured by Zeon Corporation: Quinton N180 (softening point 80°C), Quinton S195 (softening point: 94°C), Quinton DX395 (softening point: 94°C), Quinton DX390N (softening point: 93°C), Quinton D100 (softening point: 99°C), Quinton E200SN (softening point: 102°C), Quinton D200 (softening point: 102°C), Quinton Examples include N D295 (softening point: 94°C), Quinton G100B (softening point: 100°C), Quinton G115 (softening point: 115°C); and Tosoh Corporation's product names Petrotac 60 (softening point: 72°C), Petrotac 70 (softening point: 70°C), Petrotac 90 (softening point: 95°C), Petrotac 90V (softening point: 87°C), Petrotac 90HS (softening point: 87°C), and Petrotac 100V (softening point: 96°C).

[0081] Specific examples of plasticizers (2) that are C5 / C9 petroleum resin hydrides include iMarb S-100 (softening point 100°C), iMarb S-110 (softening point 110°C), and iMarb P-100 (softening point 100°C), all manufactured by Idemitsu Kosan Co., Ltd.

[0082] The content of the plasticizer (2) in the elastomer composition (3) is preferably 20% by weight or more, more preferably 25% by weight or more, preferably 50% by weight or less, and more preferably 45% by weight or less, based on 100% by weight of the elastomer composition (3).

[0083] In the elastomer composition (3), the weight ratio of the plasticizer (2) to the thermoplastic elastomer (1) (plasticizer (2) / thermoplastic elastomer (1)) is preferably 0.10 or more, more preferably 0.20 or more, and even more preferably 0.25 or more, from the viewpoint of improving the hot-melt adhesion of the elastomer film, and preferably 1.00 or less, more preferably 0.90 or less, and even more preferably 0.80 or less, from the viewpoint of effectively reducing the stickiness of the elastomer film. Here, if the elastomer composition (3) contains two or more types of plasticizers (2), the weight of the plasticizers (2) is the total weight of the two or more types of plasticizers (2).

[0084] <1.5. Optional Components> In addition to the thermoplastic elastomer (1) and plasticizer (2), the elastomer composition (3) may contain optional components. Examples of optional components include fillers; dispersants; light stabilizers such as hindered amine-based light stabilizers; ultraviolet absorbers such as benzophenone-based ultraviolet absorbers, salicylic acid-based ultraviolet absorbers, and benzotriazole-based ultraviolet absorbers; antioxidants such as phenol-based antioxidants, phosphorus-based antioxidants, and sulfur-based antioxidants; lubricants; and colorants such as pigments and dyes. Optional components may be used individually or in combination of two or more in any ratio.

[0085] The elastomer composition (3) may or may not contain a filler. The inclusion of a filler in the elastomer composition (3) can increase the storage modulus at 1 Hz and 25°C. Furthermore, it can effectively reduce the stickiness of the elastomer film. In addition, it can improve the handling properties of the elastomer film. The filler may be an inorganic substance, an organic substance, or a composite of an inorganic substance and an organic substance. Any filler with any desired function can be used. For example, hygroscopic particles can be used as a filler. Examples of hygroscopic particles used as fillers include hydrotalcite particles, zeolite particles, magnesium oxide particles, aluminum oxide particles, talc particles, titanium oxide particles, calcium oxide particles, etc., with hydrotalcite particles being preferred. When the elastomer composition (3) contains hygroscopic particles as a filler, the elastomer film can be particularly suitable for use as a hygroscopic sealing film.

[0086] The filler is usually in particulate form. The volume-average particle diameter of the filler is preferably 10 nm or more, more preferably 20 nm or more, even more preferably 50 nm or more, preferably 1000 nm or less, more preferably 500 nm or less, and even more preferably 300 nm or less. Here, the volume-average particle diameter of the filler can be measured by a laser diffraction / scattering particle size distribution analyzer. An example of a laser diffraction / scattering particle size distribution analyzer is the "LA-960V series" laser diffraction / scattering particle size distribution analyzer manufactured by Horiba, Ltd. When the volume-average particle diameter of the filler is within the above range, the dispersibility of the filler in the elastomer composition (3) can be improved.

[0087] The content of filler (which may be moisture-absorbing particles) in the elastomer composition (3) is usually 0% by weight or more, and may be 0% by weight, preferably 10% by weight or more, more preferably 20% by weight or more, preferably 45% by weight or less, more preferably 40% by weight or less, and even more preferably 35% by weight or less, with the elastomer composition (3) being 100% by weight.

[0088] When the elastomer composition (3) contains a filler (which may be a hygroscopic particle), the weight ratio of the filler to the thermoplastic elastomer (1) (filler / thermoplastic elastomer (1)) is preferably 0.50 or more, more preferably 0.60 or more, even more preferably 0.70 or more, preferably 1.30 or less, more preferably 1.2 or less, even more preferably 1.10 or less, and even more preferably 1.00 or less.

[0089] In one embodiment, the total weight ratio of the thermoplastic elastomer (1) and plasticizer (2) in the elastomer composition (3) is preferably 80% by weight or more, more preferably 90% by weight or more, even more preferably 95% by weight or more, even more preferably 97% by weight or more, and even more preferably 98% by weight or more, with the elastomer composition (3) being 100% by weight, and is usually 100% by weight or less.

[0090] When the elastomer composition (3) contains a filler as an optional component, the total weight percentage of the thermoplastic elastomer (1) and plasticizer (2) in the elastomer composition (3) is preferably 50% by weight or more, more preferably 55% by weight or more, even more preferably 60% by weight or more, with the elastomer composition (3) being 100% by weight, and is usually less than 100% by weight, preferably 90% by weight or less, and more preferably 80% by weight or less.

[0091] The elastomer composition (3) may or may not contain a dispersant. If the elastomer composition (3) contains a filler, it is preferable that the elastomer composition (3) also contains a dispersant in addition to the filler. By including a dispersant in the elastomer composition (3), the dispersibility of optional components such as fillers in the elastomer composition (3) is improved.

[0092] Examples of dispersants include compounds having a miscible group that can be miscible with a thermoplastic elastomer (1) and an adsorbent group that can be adsorbed onto the surface of the substance to be dispersed, such as a filler. Examples of commercially available dispersants include the "SOLSPERSE® series" (SOLSPERSE 3000, etc.) manufactured by Lubrizol Japan, and the "DISPERBYK® series" manufactured by BIC Chemie Japan.

[0093] The amount of dispersant in the elastomer composition (3) is usually 0% by weight or more, and may be 0% by weight, preferably 0.1% by weight or more, more preferably 1.0% by weight or more, preferably 10.0% by weight or less, more preferably 5.0% by weight or less, and even more preferably 3.0% by weight or less, based on 100% by weight of the elastomer composition (3).

[0094] When the elastomer composition (3) contains a filler and a dispersant, the weight ratio of the dispersant to the filler (dispersant / filler) is preferably 0.05 or more, more preferably 0.06 or more, even more preferably 0.07 or more, preferably 0.20 or less, more preferably 0.15 or less, and even more preferably 0.10 or less.

[0095] The elastomer composition (3) contained in the elastomer film may contain an organic solvent, but the amount is preferably small. The elastomer composition (3) may not contain an organic solvent. The organic solvent may remain in the elastomer composition (3) when the elastomer film is manufactured using a liquid composition containing a thermoplastic elastomer (1), a plasticizer (2), and an organic solvent. From the viewpoint of reducing outgassing from the elastomer film, the content of the organic solvent in the elastomer composition (3) is usually 0% by weight or more, may be 0% by weight, preferably 5% by weight or less, more preferably 4% by weight or less, and even more preferably 3% by weight or less.

[0096] <1.6. Thickness and Properties of Elastomer Film> The thickness of the elastomer film can be any thickness depending on its application. The thickness of the elastomer film is preferably 10 μm or more, more preferably 20 μm or more, and even more preferably 30 μm or more. From the viewpoint of improving optical properties such as transparency, it is preferably 800 μm or less, more preferably 500 μm or less, and even more preferably 200 μm or less.

[0097] The elastomer film may be in the form of a long roll or a single sheet. It may also be in the form of a laminate of the elastomer film with any other film, such as a release film.

[0098] The elastomer film is preferably transparent. Specifically, the total light transmittance of the elastomer film is preferably 70% or more, more preferably 80% or more, even more preferably 90% or more, and usually 100% or less. The total light transmittance can be measured in the wavelength range of 400 nm to 700 nm using an ultraviolet-visible spectrometer in accordance with JIS K7361-1. The internal haze of the elastomer film is preferably 1% or less, more preferably 0.5% or less, even more preferably 0.3% or less, and usually 0.0% or more. The internal haze can be measured using a haze meter in accordance with JIS K7136. When the elastomer film is transparent, it can be particularly suitable for use as a sealing film for sealing optical devices and as a hot-melt adhesive film for bonding optical devices and optical elements.

[0099] <2. Method for Manufacturing Elastomer Films> Elastomer films can be manufactured by any method. Preferably, elastomer films can be manufactured by a method including the following steps: Step (1): A step of applying a liquid composition containing a thermoplastic elastomer (1), a plasticizer (2), and a solvent onto a support to form a liquid composition layer. Step (2): A step of drying the liquid composition layer to obtain an elastomer film. Steps (1) and (2) are usually performed in this order.

[0100] Materials for forming the support include metals and resins. A long film may be used as the support, and the liquid composition may be continuously applied to the support to obtain a long layer of the liquid composition, which may then be dried to obtain a laminate of the long support and the elastomer film.

[0101] The support may have a single-layer structure or a multi-layer structure. A commercially available film used as a release film may be used as the support.

[0102] The method of applying the liquid composition in step (1) is not particularly limited. Examples of application methods include curtain coating, extrusion coating, roll coating, spin coating, dip coating, bar coating, spray coating, slide coating, print coating, gravure coating, die coating, and gap coating.

[0103] The drying method for the liquid composition layer in step (2) is not particularly limited. Examples of drying methods include natural drying, heat drying, reduced-pressure drying, and reduced-pressure heat drying.

[0104] The method for manufacturing an elastomer film may include any additional steps in addition to steps (1) and (2) described above. Examples of optional steps include peeling the elastomer film from the support and laminating the elastomer film with a release film.

[0105] <3. Applications of Elastomer Films> Elastomer films can be used for any application. Elastomer films soften when heated and adhere well to the object to be bonded, enabling good adhesion. Therefore, films containing elastomer films can be suitably used for hot-melt bonding. Furthermore, elastomer films soften when heated and adhere well to the object to be sealed, such as electronic devices, enabling good sealing. Therefore, films containing elastomer films can be suitably used for sealing objects such as electronic devices.

[0106] <3.1. Hot Melt Adhesive Film> A hot melt adhesive film is a film that adheres objects together by being placed between two or more objects to be bonded, then softened by heating to adhere closely to the objects, and then solidified by cooling. The hot melt adhesive film includes the elastomer film described above. The hot melt adhesive film may also be a laminate that includes any film in addition to the elastomer film, such as a release film.

[0107] Examples of materials to be bonded include glass substrates, metal substrates, and various plastic substrates.

[0108] <3.2. Sealing Film> The sealing film is a film capable of sealing an object. Examples of objects to be sealed include optical devices such as organic electroluminescent display devices, microlight-emitting diode (microLED) display devices, organic thin-film solar cell devices, and perovskite solar cell devices. The sealing film includes the elastomer film described above. The sealing film may also be a laminate that includes an optional film in addition to the elastomer film, such as a release film.

[0109] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to the examples shown below, and can be modified and implemented as appropriate without departing from the scope of the claims and equivalents of the present invention.

[0110] In the following explanation, "%" and "parts" used to express quantities refer to weight unless otherwise specified. Furthermore, the operations described below were performed under normal temperature (20°C ± 15°C) and atmospheric pressure (1 atm) conditions unless otherwise specified.

[0111] <Evaluation Method> (Method for measuring the molecular weight of polymers) Unless otherwise specified, the weight-average molecular weight (Mw), number-average molecular weight (Mn), and molecular weight distribution (Mw / Mn) of polymers were measured in polystyrene equivalent values ​​by gel permeation chromatography (GPC) using tetrahydrofuran as the solvent.

[0112] (Method for measuring the hydrogenation rate of hydrides) The hydrogenation rate of hydrides is 1 This was determined by measurement using H-NMR.

[0113] (Storage modulus and glass transition temperature of polymer at 25°C) Unless otherwise specified, the storage modulus and glass transition temperature Tg of the polymer at 1 Hz and 25°C were measured as follows. A polyethylene terephthalate film with a thickness of 38 μm (Mitsubishi Chemical Corporation's "MRV38", hereinafter also referred to as release PET film) with a release treatment applied to its surface was prepared. An ethylcyclohexane solution of polymer (a) was applied to the release PET film to a thickness of 200 μm after drying, and dried on a hot plate at 130°C to form a sample film on the release PET film. The obtained sample film was peeled off the release PET film, and a test piece with a width of 8 mm and a length of 40 mm was cut from the sample film. For the obtained test specimens, the storage modulus, loss modulus, and tanδ (loss modulus / storage modulus) were measured using a dynamic viscoelasticity analyzer (TA Instruments "DMA850") in the range of 0°C to 200°C under the conditions of a heating rate of 4°C / min, a strain of 0.05%, and a frequency of 1 Hz. From the measurement results, the storage modulus at 25°C was read and defined as the storage modulus at 25°C for polymer (a). In addition, the temperature at which tanδ showed a maximum value (tanδ peak temperature) was read from the measurement results and defined as the glass transition temperature Tg.

[0114] (Measurement of elongation at break (tensile fracture elongation)) An ethylcyclohexane solution of polymer (a) was applied to a release PET film to a thickness of 200 μm after drying, and the sample film was formed on the release PET film by drying it on a hot plate at 130°C. The obtained sample film was peeled off the release PET film, and the elongation at break (%) of the film made of polymer (a) at 25°C was measured in accordance with JIS K7127.

[0115] (Measurement of storage modulus and tanδ (1 Hz, 25°C) of elastomer composition) A liquid composition containing the elastomer composition prepared in the example or comparative example was applied to a release PET film to a thickness of 200 μm after drying, and dried on a hot plate at 130°C to form a sample film for dynamic viscoelasticity measurement on the release PET film. The obtained sample film was peeled off the release PET film, and a test piece measuring 8 mm wide x 40 mm long was cut from the sample film.

[0116] For the cut test specimens, the storage modulus and loss modulus were measured using a dynamic viscoelasticity analyzer (TA Instruments "DMA850") with a heating rate of 4°C / min, a strain of 0.05%, and frequencies of 1 Hz, 5 Hz, and 10 Hz, with the measurement temperature ranging from -120°C to 100°C. From the measurement results of the storage modulus at a frequency of 1 Hz, the value of the storage modulus at 100°C was read and defined as the storage modulus at 1 Hz and 100°C.

[0117] Furthermore, based on the measurement results, a master curve of the storage modulus at a reference temperature of 25°C was created using the software attached to the device. From this master curve, the storage modulus at 1 Hz and the storage modulus at 10,000 Hz were read and used as the storage modulus at 1 Hz and 25°C, and the storage modulus at 10,000 Hz and 25°C, respectively. In addition, a master curve of the loss modulus at a reference temperature of 25°C was created, and from this master curve, the loss modulus at 1 Hz was read and used as the loss modulus at 1 Hz and 25°C.

[0118] From the loss modulus and storage modulus obtained at 1 Hz and 25°C as described above, tanδ (1 Hz, 25°C) was determined.

[0119] (Evaluation of stickiness) A rectangular laminate piece measuring 5 cm x 5 cm was cut from the laminate obtained in the example or comparative example. In an environment of 25°C, the laminate piece was placed on a 5 cm square glass plate so that the surface of the elastomer film exposed on the laminate piece faced the surface of the glass plate, and a force was applied to the laminate piece in a direction parallel to the glass plate. If the laminate piece slid and moved, it was evaluated as not being sticky. If the laminate piece did not move, it was evaluated as being sticky. If there is no stickiness, it is easy to place the laminate piece in the desired location on the glass plate.

[0120] (Hot melt adhesion: Adhesion to the object to be bonded) A rectangular laminate piece measuring 5 cm x 5 cm was cut from the laminate obtained in the example or comparative example. The laminate piece was sandwiched between two 5 cm square, 0.7 mm thick glass plates and bonded together in a heated vacuum laminator at 0.5 MPa and 100°C. The adhesion between the elastomer film and the glass plates after hot melt bonding was evaluated based on the presence or absence of air bubbles between the glass plates. The evaluation criteria are as follows: A: No air bubbles are observed. B: Fine air bubbles are observed in some areas. C: Streaky air bubbles are observed across the entire surface.

[0121] <Components used in the examples or comparative examples> The components used in the examples or comparative examples are as follows: (Thermoplastic elastomer (1)) Polymer (a): Silane-modified product of the hydrogenated block copolymer produced in Production Example 1 below (modified product with silicon atom-containing polar group)

[0122] (Filler) Hydrotalcite

[0123] (Plasticizers (2)) C9_P90: C9-based petroleum resin hydride "Alcon P-90" (softening point 90°C) (manufactured by Arakawa Chemical Industries, Ltd.) C9_P115: C9-based petroleum resin hydride "Alcon P-115" (softening point 115°C) (manufactured by Arakawa Chemical Industries, Ltd.) C9_P140: C9-based petroleum resin hydride "Alcon P-140" (softening point 140°C) (manufactured by Arakawa Chemical Industries, Ltd.) Polybutene: "NOF Polybutene 10N" (softening point 23°C or less: liquid at 23°C) (manufactured by NOF Corporation) C5 / C9_N180: C5 / C9-based petroleum resin "Quinton N180" (softening point 80°C) (manufactured by Nippon Zeon Corporation) C5_B170: C5-based petroleum resin "Quinton B170" (softening point 70°C) (manufactured by Zeon Corporation)

[0124] (Dispersant) "SOLSPERSE 3000" (manufactured by Lubrizol Japan Co., Ltd.)

[0125] <Production Example 1: Production of Polymer (a) Having Polar Groups Containing Silicon Atoms> (Production of Hydrogenated Block Copolymer) Using styrene as the aromatic vinyl compound and isoprene as the chain-like conjugated diene compound, a hydrogenated block copolymer having a triblock structure in which polymer blocks [A] are bonded to both ends of polymer block [B] was produced by the following procedure.

[0126] In a reactor equipped with a stirring device and thoroughly purged with nitrogen, 256 parts of dehydrated cyclohexane, 25.0 parts of dehydrated styrene, and 0.615 parts of n-dibutyl ether were added. While stirring at 60°C, 1.35 parts of n-butyllithium (15% cyclohexane solution) were added to initiate polymerization, and the reaction was continued at 60°C for 60 minutes with further stirring. At this point, the polymerization conversion rate was 99.5% (the polymerization conversion rate was measured by gas chromatography; the same method was used hereafter).

[0127] Next, 50.0 parts of dehydrated isoprene were added, and stirring was continued at the same temperature for 30 minutes. At this point, the polymerization conversion rate was 99%. Subsequently, 25.0 parts of dehydrated styrene were added, and stirring was continued at the same temperature for 60 minutes. At this point, the polymerization conversion rate was approximately 100%. Then, 0.5 parts of isopropyl alcohol were added to the reaction solution to stop the reaction and obtain solution (i) containing the block copolymer. The weight-average molecular weight (Mw) of the block copolymer in the obtained solution (i) was 44,900, and the molecular weight distribution (Mw / Mn) was 1.03. The weight fraction of styrene block / weight fraction of isoprene block in the block copolymer was 50 / 50.

[0128] Next, solution (i) was transferred to a pressure reactor equipped with a stirring device, and 4.0 parts of silica-alumina-supported nickel catalyst (E22U, nickel load 60%; manufactured by JGC Chemical Industries, Ltd.) and 350 parts of dehydrated cyclohexane were added to solution (i) as a hydrogenation catalyst and mixed. The reactor was purged with hydrogen gas, and hydrogen was supplied while stirring the solution, and the hydrogenation reaction was carried out at a temperature of 170°C and a pressure of 4.5 MPa for 6 hours to hydrogenate the block copolymer and obtain solution (iii) containing the hydride (ii) of the block copolymer. The weight-average molecular weight (Mw) of the hydride (ii) in solution (iii) was 45,100, and the molecular weight distribution (Mw / Mn) was 1.04.

[0129] After the hydrogenation reaction was complete, solution (iii) was filtered to remove the hydrogenation catalyst. Then, 1.0 part of a xylene solution containing 0.1 part of the phosphorus-based antioxidant 6-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetrakis-t-butyldibenzo[d,f][1.3.2]dioxaphosfepine (Sumitomo Chemical Co., Ltd., "SumiLizer® GP"; hereinafter referred to as "antioxidant A") was added to the filtered solution (iii) and dissolved to obtain solution (iv).

[0130] Next, solution (iv) was filtered through a ZetaPlus® filter 30H (manufactured by Quno, pore size 0.5 μm to 1 μm), and then sequentially filtered through another metal fiber filter (pore size 0.4 μm, manufactured by Nichidai) to remove minute solid particles. From the filtered solution (iv), cyclohexane, xylene, and other volatile components were removed using a cylindrical concentrate dryer (product name "Contro", manufactured by Hitachi, Ltd.) at a temperature of 260°C and a pressure of 0.001 MPa or less. The solid particles were then extruded in a molten state into strands from a die directly connected to the concentrate dryer, cooled, and cut with a pelletizer to obtain 85 parts of pellet (v) containing hydride of block copolymer and antioxidant A. The weight-average molecular weight (Mw) of the hydride of block copolymer (hydrogenated block copolymer) in the obtained pellet (v) was 45,000, and the molecular weight distribution (Mw / Mn) was 1.08. Furthermore, the hydrogenation rate was 99.9%.

[0131] (Preparation of silane-modified hydrogenated block copolymer) 2.0 parts vinyltrimethoxysilane and 0.2 parts di-t-butyl peroxide were added to 100 parts pellet (v) to obtain a mixture. This mixture was kneaded using a twin-screw extruder at a barrel temperature of 210°C and a residence time of 80 to 90 seconds. The kneaded mixture was extruded and cut with a pelletizer to obtain pellet (vi) of a silane-modified hydrogenated block copolymer (modified by silicon atom-containing polar groups), which is polymer (a) having polar groups containing silicon atoms. A film-like test piece was prepared from this pellet (vi), and the glass transition temperature Tg was evaluated using the tanδ peak of a dynamic viscoelasticity measuring instrument by the method described above, and was found to be 124°C. Furthermore, the storage modulus at 25°C and 1 Hz was 0.22 GPa, and the elongation at break at 25°C was 520%, indicating that polymer (a) was a thermoplastic elastomer.

[0132] <Example 1> (1-1. Preparation of a liquid composition containing an elastomer composition) A liquid composition containing an elastomer composition was prepared by mixing 40 parts of polymer (a) as a thermoplastic elastomer produced in Production Example 1, 22 parts of hydrogenated C9 petroleum resin "Alcon P-90" (manufactured by Arakawa Chemical Industries, Ltd.) as a plasticizer, 35 parts of hydrotalcite as a filler, 3 parts of "SOLSPERSE 3000" (manufactured by Lubrizol Nippon Co., Ltd.) as a filler dispersant, and 200 parts of ethylcyclohexane to disperse the filler. The volume-average particle size of the filler measured from this liquid composition was 125 nm. The volume-average particle size of the filler was measured using a laser diffraction / scattering particle size distribution analyzer "LA-960V series" manufactured by Horiba, Ltd., based on the laser diffraction method. The measurement temperature was 25°C.

[0133] Furthermore, test specimens formed from the elastomer composition for dynamic viscoelasticity measurement were prepared from this liquid composition using the method described above, and the storage modulus and tanδ (1 Hz, 25°C) of the elastomer composition were measured. The storage modulus and tanδ (1 Hz, 25°C) of the elastomer composition are shown in the table below. The weight percentages of each component in the elastomer composition (composition obtained by removing the solvent ethylcyclohexane from the liquid composition) are shown in the table below.

[0134] (1-2. Manufacturing of Elastomer Film) Next, a liquid composition containing the elastomer composition was applied to a PET film with a thickness of 38 μm and release layers formed on both sides, so that the film thickness after drying would be 50 μm, and it was dried in a drying oven at 130°C. This yielded a laminate containing a long elastomer film. This laminate had a layer structure of (PET film with release layers formed on both sides) / (elastomer film with a thickness of 50 μm) and was wound onto a plastic core in a roll shape. From the obtained laminate, a piece of the laminate was cut out as described above, and the stickiness and hot-melt adhesion of the elastomer film were evaluated using the method described above. Even when the PET film with the release layer was peeled off from the laminate and only the elastomer film remained, the elastomer film maintained its shape.

[0135] <Examples 2-9, Comparative Examples 1-5> The types and / or weight ratios of thermoplastic elastomer, filler, plasticizer, and dispersant were changed as shown in Table 1 or Table 2. In Tables 1 and 2, the respective weight ratios of thermoplastic elastomer, filler, plasticizer, and dispersant represent the weight ratio when the total weight of thermoplastic elastomer, filler, plasticizer, and dispersant is set to 100% by weight (100 parts). Except for the above, a liquid composition containing the elastomer composition was prepared and a laminate containing the elastomer film was manufactured by the same procedure as in Example 1. Using the obtained laminate, the stickiness and hot-melt adhesion of the elastomer film were evaluated by the same procedure as in Example 1. Even when the PET film with the release layer formed was peeled off from the laminates obtained in Examples 2-9 and Comparative Examples 1-5, leaving only the elastomer film, the elastomer film maintained its shape.

[0136] <Results> The results are shown in the table below. The ingredients and abbreviations listed in the table have the following meanings. Filler: Hydrotalcite C9_P90: C9-based petroleum resin hydride "Alcon P-90" (softening point 90°C) (manufactured by Arakawa Chemical Industries, Ltd.) C9_P115: C9-based petroleum resin hydride "Alcon P-115" (softening point 115°C) (manufactured by Arakawa Chemical Industries, Ltd.) C9_P140: C9-based petroleum resin hydride "Alcon P-140" (softening point 140°C) (manufactured by Arakawa Chemical Industries, Ltd.) Polybutene: "NOF Polybutene 10N" (softening point 23°C or less) (manufactured by NOF Corporation) C5 / C9_N180: C5 / C9-based petroleum resin "Quinton N180" (softening point 80°C) (manufactured by Nippon Zeon Corporation) C5_B170: C5-based petroleum resin "Quinton B170" (softening point 70°C) (manufactured by Nippon Zeon Corporation) Dispersant: "SOLSPERSE3000" G' 1Hz 25℃: Storage modulus at 1Hz and 25℃ G' 1Hz 100℃: Storage modulus at 1Hz and 100℃ G' 10000Hz 25℃: Storage modulus at 10000Hz and 25℃ tanδ 1Hz 25℃: Ratio of loss modulus to storage modulus at 1Hz and 25℃ (2) / (1): Weight percentage of plasticizer (2) to thermoplastic elastomer (1) (plasticizer (2) / thermoplastic elastomer (1)) In the table below, "%" means "weight %" with the elastomer composition (composition obtained by removing the solvent from the liquid composition) as 100% by weight. *1: Not measured.

[0137]

[0138]

[0139] From the above results, the elastomer films comprising an elastomer composition containing a thermoplastic elastomer (polymer (a)) and a plasticizer having a softening point of 25°C or higher, wherein the elastomer composition has a storage modulus of 0.10 GPa or higher at 1 Hz and 25°C, and a storage modulus of 1.00 MPa or lower at 1 Hz and 100°C, are not sticky and have a good hot melt adhesion evaluation of A. On the other hand, the elastomer film according to Comparative Example 1, whose storage modulus at 1 Hz and 25°C is less than 0.10 GPa, is sticky at 25°C. Furthermore, the elastomer films according to Comparative Examples 2 to 5, whose storage modulus at 1 Hz and 100°C is greater than 1.00 MPa, have a poor hot melt adhesion evaluation of B or C.

Claims

1. An elastomer film comprising an elastomer composition containing a thermoplastic elastomer (1) and a plasticizer (2) having a softening point of 25°C or higher, wherein the elastomer composition has a storage modulus of 0.10 GPa or higher at 1 Hz and 25°C, and a storage modulus of 1.00 MPa or lower at 1 Hz and 100°C.

2. The elastomer film according to claim 1, wherein the elastomer composition has a storage modulus of 1.0 GPa or more at 10,000 Hz and 25°C.

3. The elastomer film according to claim 1, wherein the elastomer composition has a ratio of loss modulus to storage modulus of 0.10 or more at 1 Hz and 25°C.

4. The elastomer film according to claim 1, wherein the thermoplastic elastomer (1) is one or more selected from the group consisting of aromatic vinyl compound-conjugated diene block copolymer, aromatic vinyl compound-conjugated diene block copolymer modified by a silicon atom-containing polar group, hydrogenated aromatic vinyl compound-conjugated diene block copolymer, and hydrogenated aromatic vinyl compound-conjugated diene block copolymer modified by a silicon atom-containing polar group.

5. The elastomer film according to claim 1, wherein the content of the plasticizer (2) in the elastomer composition is 20% by weight or more and 50% by weight or less based on 100% by weight of the elastomer composition.

6. The elastomer film according to claim 1, wherein the plasticizer (2) is one or more selected from the group consisting of petroleum resins and petroleum resin hydrides.

7. The elastomer film according to claim 1, wherein the plasticizer (2) is one or more selected from the group consisting of C5 petroleum resin, C9 petroleum resin hydride, C5 / C9 petroleum resin, and C5 / C9 petroleum resin hydride.

8. The elastomer film according to claim 1, wherein the elastomer composition further comprises moisture-absorbing particles.

9. A hot-melt adhesive film comprising the elastomer film described in any one of claims 1 to 8.

10. A sealing film comprising the elastomer film according to any one of claims 1 to 8.

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