Polymerizable compound, curable resin composition, and sealing agent for display element

Abstract

The present invention provides: a polymerizable compound from which a cured product having excellent bending resistance is obtained and with which the surface tackiness of the cured product is suppressed; a curable resin composition comprising said polymerizable compound; and a sealing agent for a display element, the sealing agent comprising said curable resin composition. The present invention pertains to a polymerizable compound represented by formula (1v). In formula (1v), av represents an integer of at least 0, Rvs each independently represent a C2-C10 organic group, at least one Rv has an alkylene glycol skeleton in which the number of repetitions of a C2-C6 alkylene unit is at least 1, and R1v and R2v each independently represent a C2-C10 organic group.

Description

Polymerizable compounds, curable resin compositions, and encapsulants for display elements

[0001] This invention relates to polymerizable compounds. Furthermore, this invention relates to a curable resin composition containing a polymerizable compound, and a encapsulant for display elements comprising the curable resin composition.

[0002] In recent years, liquid crystal displays and organic EL displays have been widely used as display elements that are thin, lightweight, and have low power consumption. For example, a liquid crystal display is usually manufactured by placing two transparent substrates with electrodes opposite each other at a predetermined distance apart, sealing the periphery with a sealant to form a cell, and injecting liquid crystal into the cell through a liquid crystal injection port provided in a part of the cell. Curable resin compositions containing polymerizable compounds are used for sealing liquid crystals in this way.

[0003] As a technology relating to curable resin compositions, for example, Patent Document 1 discloses a photocurable adhesive for polarizing plates that contains a polythiol compound having two or more thiol groups in one molecule, a polyene compound having two or more carbon-carbon double bonds in one molecule, and a photopolymerization initiator.

[0004] Patent Document 2 contains a polythiol monomer having two or more thiol groups in one molecule, a polyene monomer having two or more carbon-carbon double bonds in one molecule, and a photopolymerization initiator, with a volume resistivity of 5.0 × 10 at 30°C. １０ A encapsulant for display elements is disclosed, having a viscosity of Ω or more, and a viscosity of 0.4 to 8 Pa·s measured using a cone-rotor viscometer at 20°C and 20 rpm.

[0005] Patent Document 3 discloses a photocurable resin composition comprising a polyene compound having two or more carbon-carbon double bonds in one molecule, a polythiol compound having two or more thiol groups in one molecule, and a photopolymerization initiator, wherein the acid value is 3 or less.

[0006] Patent Document 4 discloses a crosslinked coating film obtained by crosslinking a crosslinkable resin composition, wherein the crosslinked coating film has a glass transition temperature of -30 to 60°C, a storage modulus in a dynamic viscoelasticity test of 0.1 to 1,000 MPa in the range of -30 to -10°C and 0.01 to 5 MPa in the range of 80 to 150°C, and an elongation of 30% or more in an atmosphere of 25°C.

[0007] Japanese Patent Publication No. 2005-139401, Japanese Patent Publication No. 2016-074784, Japanese Patent Publication No. Hei 6-306172, International Publication No. 2017 / 056141

[0008] In recent years, with the widespread use of foldable smartphones, it has become necessary for the encapsulant itself to not crack or peel when bent. Furthermore, if tack remains on the surface of the encapsulant, it poses a risk of foreign matter adhesion, so it is also required to reduce surface tackiness. Although curable resin compositions described in Patent Documents 1 to 4 were known, there was room for improvement in further enhancing the bending resistance of the cured product and suppressing the surface tackiness of the cured product. The present invention aims to provide a polymerizable compound that exhibits excellent bending resistance of the cured product and suppresses the surface tackiness of the cured product, a curable resin composition containing the polymerizable compound, and an encapsulant for display elements made from the curable resin composition.

[0009] Disclosure 1 is a polymerizable compound represented by the following formula (1v).

[0010]

[0011] In formula (1v), a ｖ represents a non-negative integer, R ｖ Each of these independently represents an organic group having 2 to 10 carbon atoms, and at least one R ｖ It has an alkylene glycol skeleton in which the number of repeating alkylene units having 2 to 6 carbon atoms is 1 or more, R １ｖ and R ２ｖ Each of these independently represents an organic group having 2 to 10 carbon atoms. In the above formula (1v), R ｖThe polymerizable compound according to the present disclosure 1, wherein the number of carbon atoms in the alkylene unit contained in the alkylene glycol skeleton of is 3 or 4. In the present disclosure 3, in the above formula (1v), at least one R ｖ is the polymerizable compound according to the present disclosure 1 or 2 having a structure represented by the following formula (2v).

[0012]

[0013] In formula (2v), * represents a bonding hand.

[0014] In the present disclosure 4, in the above formula (1v), at least one R ｖ is the polymerizable compound according to any one of the present disclosures 1, 2 or 3 having a structure represented by the following formula (3v).

[0015]

[0016] In formula (3v), * represents a bonding hand, and k ｖ represents 1 or 2, and m ｖ represents 0, 1 or 2, and n ｖ represents 0, 1 or 2, and m ｖ and n ｖ are never both 0. The present disclosure 5 is a curable resin composition containing the polymerizable compound according to any one of the present disclosures 1, 2, 3 and 4. The present disclosure 6 is the curable resin composition according to the present disclosure 5, further containing a polythiol compound having a plurality of thiol groups in one molecule and a polymerization initiator. The present disclosure 7 is obtained by applying the curable resin composition onto a base material so as to have a thickness of 500 µm, and having a wavelength of 365 nm and an illuminance of 100 mW / cm ２ The curable resin composition according to the present disclosure 5 or 6, wherein a cured product obtained by irradiating with light of 30 seconds has a storage elastic modulus at -20°C of 500 MPa or less. The present disclosure 8 is a sealant for a display element, which is composed of the curable resin composition according to any one of the present disclosures 5, 6 or 7. The present invention is described in detail below.

[0017] The inventors focused on polymerizable compounds to be included in a curable resin composition in order to obtain a cured product with excellent bending resistance and suppressed surface tackiness, and investigated the chemical structure of such polymerizable compounds. As a result, they found that by using a polymerizable compound having a specific chemical structure, it is possible to increase the flexibility of the cured product and suppress the decrease in the reactivity of the cured product surface due to oxygen, etc., thereby obtaining a cured product with excellent bending resistance and suppressed surface tackiness, and thus completed the present invention.

[0018] The polymerizable compounds of this disclosure are represented by the following formula (1v) and are also called polyene monomers or polyene compounds.

[0019]

[0020] In formula (1v), a ｖ represents a non-negative integer, R ｖ Each of these independently represents an organic group having 2 to 10 carbon atoms, and at least one R ｖ It has an alkylene glycol skeleton in which the number of repeating alkylene units having 2 to 6 carbon atoms is 1 or more, R １ｖ and R ２ｖ Each of these independently represents an organic group with 2 to 10 carbon atoms.

[0021] The polymerizable compound represented by formula (1v) above has a highly flexible diphenylmethane-derived structure in its main chain, resulting in a cured product with high bending resistance. Thus, because the cured product of the polymerizable compound of this disclosure has high bending resistance (flexibility), it can be suitably used as a peripheral sealing agent for the casing of foldable smartphones and the like.

[0022] Furthermore, the polymerizable compound represented by the above formula (1v) has high cohesive force derived from the diphenylmethane skeleton, which suppresses the decrease in the reactivity of the cured product surface due to oxygen, etc., and can reduce the surface tackiness of the cured product.

[0023] Furthermore, considering the coating process such as dispensing, a viscosity of several hundred mPa·s or higher is preferable for encapsulants for display elements. However, it has been difficult to achieve high viscosity while maintaining high bending resistance with conventional encapsulants for display elements. On the other hand, as described above, the polymerizable compound of this disclosure achieves high bending resistance and low surface tack in the cured product, while the viscosity and reactivity of the polymerizable compound can be increased by the allyl groups located at both ends of the main chain.

[0024] In formula (1v), a ｖ The lower limit is 0. ｖ By having a value greater than or equal to 0, high viscosity and high cohesive force derived from the urethane skeleton can be achieved. ｖ The preferred lower limit of is 1, and the more preferred lower limit is 3. In equation (1v), a ｖ The preferred upper limit is 30. ｖ By having an integer less than or equal to 30, the compatibility between the polymerizable compound and other resins can be improved. ｖ A more preferable upper limit is 20, and an even more preferable upper limit is 10.

[0025] In formula (1v), R ｖ Each of these independently represents an organic group having 2 to 10 carbon atoms. By having a lower limit of 2 carbon atoms in the organic group, a high cohesive force derived from the urethane skeleton of the main chain can be expressed. A preferred lower limit for the number of carbon atoms in the organic group is 3, and a more preferred lower limit is 5. Furthermore, by having an upper limit of 10 carbon atoms in the organic group, phase separation can be suppressed, and a transparent liquid state can be maintained. A preferred upper limit for the number of carbon atoms in the organic group is 9, and a more preferred upper limit is 8.

[0026] R ｖ The above-mentioned organic group having 2 to 10 carbon atoms, represented by the above, preferably contains an alkylene group. Examples include a group having one or more constituent units of polyether, a group having one or more constituent units of polypropylene, a group having one or more constituent units of polytetramethylene ether, a group having one or more constituent units of polyester, a group having one or more constituent units of polycarbonate, and a group derived from glycerin monoallyl ether.

[0027] In the above formula (1v), at least one Rｖ R has an alkylene glycol skeleton in which the number of repeating alkylene units having 2 to 6 carbon atoms is 1 or more. ｖ If multiple elements are present in one molecule, their structures may be identical to each other, or at least one may be different from the others. Furthermore, from the viewpoint of further reducing surface tackiness, the alkylene glycol skeleton is preferably linear.

[0028] R ｖ The lower limit of the number of repeating alkylene units contained in the alkylene glycol skeleton is 1. A high viscosity liquid compound can be obtained when the number of repeating units is 1 or more. The preferred lower limit of the number of repeating units is 2.

[0029] R ｖ The preferred upper limit for the number of repeating alkylene units contained in the alkylene glycol skeleton is 50. A high viscosity liquid compound can be obtained when the number of repeating units is 50 or less. A more preferred upper limit for the number of repeating units is 10.

[0030] R ｖ The number of carbon atoms in the alkylene unit contained in the alkylene glycol skeleton is preferably 3 or 4. Having 3 or 4 carbon atoms in the alkylene unit allows for obtaining a compound that is liquid at room temperature.

[0031] R ｖ Examples of the alkylene glycol skeletons possessed by the above-mentioned material include ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, and the like.

[0032] In the above formula (1v), at least one R ｖ It is preferable that it has a structure represented by the following formula (2v): at least one R ｖ The structure represented by the following formula (2v) suppresses the formation of a phase separation structure during resin curing, making it possible to obtain a transparent cured product.

[0033]

[0034] In equation (2v), * represents a coupling.

[0035] In the above formula (1v), at least one R ｖ It is preferable that it has a structure represented by the following formula (3v): at least one R ｖ The structure represented by the following formula (3v) suppresses the formation of a phase separation structure during resin curing, making it possible to obtain a transparent cured product.

[0036]

[0037] In equation (3v), * represents a coupling, and k ｖ represents 1 or 2, m ｖ represents 0, 1, or 2, and n ｖ represents 0, 1, or 2, m ｖ and n ｖ Neither of these can be zero. This allows for excellent transparency and flexibility.

[0038] In formula (1v), R １ｖ and R ２ｖ Each of these independently represents an organic group having 2 to 10 carbon atoms. By having a lower limit of 2 carbon atoms in the organic group, a high cohesive force derived from the urethane skeleton of the main chain can be expressed. A preferred lower limit for the number of carbon atoms in the organic group is 3, and a more preferred lower limit is 5. Furthermore, by having an upper limit of 10 carbon atoms in the organic group, phase separation can be suppressed, and a transparent liquid state can be maintained. A preferred upper limit for the number of carbon atoms in the organic group is 9, and a more preferred upper limit is 8.

[0039] R １ｖ and R ２ｖ The above-mentioned organic group having 2 to 10 carbon atoms, represented by the above, preferably contains an alkylene group. Examples include a group having one or more constituent units of polyether, a group having one or more constituent units of polypropylene, a group having one or more constituent units of polytetramethylene ether, a group having one or more constituent units of polyester, a group having one or more constituent units of polycarbonate, and a group derived from glycerin monoallyl ether.

[0040] R １ｖ The formula is as follows (R １ｖ -1) or (R １ｖ-2) is preferable.

[0041]

[0042] R ２ｖ The formula is as follows (R ２ｖ -1) or (R ２ｖ -2) is preferable.

[0043]

[0044] Formula (R １ｖ -1), (R １ｖ -2), (R ２ｖ -1) and (R ２ｖ -2) In the above, * represents a bonding hand, b ｖ This represents an integer between 1 and 140.

[0045] Formula (R １ｖ -1), (R １ｖ -2), (R ２ｖ -1) and (R ２ｖ -2) Medium, b ｖ The preferred upper limit is 30. ｖ By having a value less than or equal to 30, a flexible cured product with sufficient crosslinking density can be obtained. ｖ A more preferable upper limit is 10, and an even more preferable upper limit is 5.

[0046] The polymerizable compound represented by the above formula (1v) can be synthesized, for example, by the following method: A polyol and a polyisocyanate are heated at 80°C for 3 hours, and after the temperature rise stabilizes, the reaction is carried out at 100°C to obtain a urethane prepolymer. Then the temperature is raised to 80°C, a basic catalyst is added, and a monoallylated polyether is added, and the mixture is stirred and reacted for 3 hours to obtain the polymerizable compound represented by the above formula (1v). IR measurement revealed approximately 2260 cm⁻¹, which originates from the isocyanate group. －１The reaction endpoint is determined by the disappearance of the peak. As monoallylated polyethers, for example, allyl glycol manufactured by Nippon Emulsifier Co., Ltd., and Uniox PKA-5001, Uniox PKA-5002, Uniox PKA-5003, Uniox PKA-5004, Uniox PKA-5005, Uniox PKA-5011, Uniox PKA-5013, Uniox PKA-5014TF, Uniox PKA-5015, Uniox PKA-5016, and Uniox PKA-5017 manufactured by NOF Corporation can be used.

[0047] The curable resin composition of this disclosure contains a polymerizable compound represented by the above formula (1v). The polymerizable compound represented by the above formula (1v) may be used alone or in combination of two or more types. As described above, the polymerizable compound of this disclosure has excellent bending resistance of the cured product, and therefore the curable resin composition of this disclosure also has excellent bending resistance of the cured product. Furthermore, as described above, the polymerizable compound of this disclosure can reduce the surface tackiness of the cured product, and therefore the curable resin composition of this disclosure can also reduce the surface tackiness of the cured product. Furthermore, as described above, the polymerizable compound of this disclosure can increase the viscosity and reactivity of the polymerizable compound. Therefore, the curable resin composition of this disclosure can also increase the viscosity and reactivity of the curable resin composition.

[0048] The preferred lower limit for the content of the polymerizable compound represented by formula (1v) in the above curable resin composition is 10% by mass, and the preferred upper limit is 80% by mass. By having the content of the polymerizable compound represented by formula (1v) within this range, a cured product with high flexibility and low surface tack can be obtained. The more preferred lower limit for the content of the polymerizable compound represented by formula (1v) is 20% by mass, and the more preferred upper limit is 70% by mass.

[0049] Preferably, the above curable resin composition further contains a polythiol compound having multiple thiol groups in one molecule and a polymerization initiator. Incidentally, when the curable resin composition of this disclosure is used as a encapsulant for a display element, if the curable resin composition in the form of a coating is cured with one side of the coating exposed to air, surface reactivity (surface curability) in the atmosphere becomes important. Also, if tack remains on the surface, it poses a risk of foreign matter adhesion, so it is necessary to reduce surface tackiness. By including a polythiol compound having multiple thiol groups in one molecule and a polymerization initiator in addition to the polymerizable compound represented by the above formula (1v), it is possible to increase the surface reactivity of the curable resin composition in the atmosphere. As a result, the surface tackiness of the cured product of the curable resin composition of this disclosure can be further reduced.

[0050] The above-mentioned polythiol compound is a compound having multiple thiol groups in one molecule. Preferably, the thiol groups of the above-mentioned polythiol compound are secondary thiol groups. The fact that the thiol groups of the above-mentioned polythiol compound are secondary thiol groups results in a curable resin composition having excellent storage stability.

[0051] From the viewpoint of reactivity and flexibility, the above polythiol compound preferably has two to four thiol groups per molecule, and more preferably has two to three thiol groups.

[0052] Examples of the polythiol compounds having two thiol groups in one molecule include 1,4-bis(3-mercaptobutyryloxy)butane, trimethylolpropanedipropanthol, butanediol bisthiopropionate, ethylenebis(3-mercaptopropionate), 1,2-bis(2-mercaptoethoxy)ethane, and ethylenebis(thioglycolate). These polythiol compounds having two thiol groups in one molecule may be used individually or in combination of two or more.

[0053] Examples of the polythiol compounds having three or more thiol groups in one molecule include pentaerythritol trippropanthol, 1,3,5-tris(2-(3-sulfanylbutanoyloxy)ethyl)-1,3,5-triazinane-2,4,6-trione, pentaerythritol tetrakis(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptopropionate), and dipentaerythritol hexakis(3-mercaptopropionate). These polythiol compounds having three or more thiol groups in one molecule may be used individually or in combination of two or more.

[0054] The preferred lower limit for the content of the polythiol compound in the above curable resin composition is 10% by mass, and the preferred upper limit is 60% by mass. By having the content of the polythiol compound within this range, a cured product with excellent flexibility can be obtained. The more preferred lower limit for the content of the polythiol compound is 15% by mass, and the more preferred upper limit is 50% by mass.

[0055] Examples of polymerization initiators include photopolymerization initiators and thermal polymerization initiators, with photopolymerization initiators being preferred.

[0056] Examples of the above-mentioned photopolymerization initiators include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, and thioxanthone compounds. Examples of the above-mentioned photopolymerization initiators include, specifically, 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-(dimethylamino)-2-((4-methylphenyl)methyl)-1-(4-(4-morpholinyl)phenyl)-1-butanone, 2,2-dimethoxy-1,2-diphenylethane-1-one, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 1-(4-(2-hydroxyethoxy)-phenyl)-2-hydroxy-2-methyl-1-propan-1-one, 1-(4-(phenylthio)phenyl)-1,2-octanedione 2-(O-benzoyloxime), and 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TPO). The above photopolymerization initiators may be used alone or in combination of two or more.

[0057] Examples of the thermal polymerization initiators include those composed of azo compounds and organic peroxides. Examples of the azo compounds include those having a structure in which multiple units such as polyalkylene oxide or polydimethylsiloxane are bonded via an azo group. As for polymer azo compounds having a structure in which multiple units such as polyalkylene oxide are bonded via an azo group, those having a polyethylene oxide structure are preferred. Specific examples of the azo compounds include polycondensates of 4,4'-azobis(4-cyanopentanoic acid) and polyalkylene glycol, and polycondensates of 4,4'-azobis(4-cyanopentanoic acid) and polydimethylsiloxane having terminal amino groups. Examples of the organic peroxides include ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, peroxyesters, diacyl peroxides, and peroxydicarbonates.

[0058] The preferred lower limit for the content of the polymerization initiator in the above curable resin composition is 0.1% by mass, and the preferred upper limit is 5% by mass. Having the polymerization initiator content within this range allows for excellent UV curability. A more preferred lower limit for the content of the polymerization initiator is 0.5% by mass, and a more preferred upper limit is 2% by mass.

[0059] The curable resin composition of this disclosure preferably further contains a polymerizable compound (hereinafter simply referred to as "other polyfunctional polymerizable compound") that does not have the structure represented by formula (1v) above and has two or more polymerizable unsaturated double bonds (also referred to as "aliphatic carbon-carbon double bonds") in one molecule. By containing other polyfunctional polymerizable compounds in the curable resin composition, the viscosity and reactivity of the curable resin composition can be increased. A polymerizable compound that does not have the structure represented by formula (1v) above and has one polymerizable unsaturated double bond in one molecule is also referred to as "other monofunctional polymerizable compound".

[0060] The above-mentioned other polyfunctional polymerizable compounds are preferably monomers, and examples include diallyl isophthalate, diallyl phthalate, diallyl maleate, diallyl diphenate, triallyl isocyanurate, pentaerythritol tetraallyl ether, and 1,3,4,6-tetraallyltetrahydroimidazo[4,5-d]imidazole-2,5(1H,3H)-dione.

[0061] The above-mentioned other polyfunctional polymerizable compounds are preferably (meth)allyl monomers having two or three polymerizable unsaturated double bonds in one molecule. The other polyfunctional polymerizable compounds may be used individually or in combination of two or more.

[0062] The preferred lower limit and preferred upper limit of the content of the above-mentioned other polyfunctional polymerizable compounds in the curable resin composition of this disclosure is 5% by mass. By having the content of the above-mentioned other polyfunctional polymerizable compounds within this range, the viscosity and reactivity of the resulting curable resin composition can be further increased. A more preferred lower limit and a more preferred upper limit of 40% by mass are for the content of the above-mentioned other polyfunctional polymerizable compounds.

[0063] In the curable resin composition of this disclosure, the preferred lower limit of the content of (meth)allyl monomer having two or three polymerizable unsaturated double bonds in one molecule is 5% by mass, and the preferred upper limit is 45% by mass. By having the content of (meth)allyl monomer having two or three polymerizable unsaturated double bonds in one molecule within this range, the viscosity and reactivity of the resulting curable resin composition can be further increased. A more preferred lower limit of the content of (meth)allyl monomer having two or three polymerizable unsaturated double bonds in one molecule is 10% by mass, and a more preferred upper limit is 40% by mass.

[0064] The curable resin composition of this disclosure may further contain a coloring agent. By including a coloring agent in the curable resin composition of this disclosure, for example, light-shielding properties or design properties can be imparted to the cured product.

[0065] The above-mentioned coloring agent may be a pigment or a dye. Specific examples of the above-mentioned coloring agent include ultraviolet-transmitting dyes, titanium black, zirconium nitride, carbon black, iron oxide, aniline black, cyanine black, and the like.

[0066] The above-mentioned ultraviolet-transmitting dye, titanium black, and zirconium nitride are pigments with low light transmittance in the visible light region and high light transmittance near the ultraviolet region. That is, the above-mentioned ultraviolet-transmitting dye, titanium black, and zirconium nitride absorb all or part of the wavelengths of light in the visible light region, thereby imparting light-shielding properties and design properties to the curable resin composition of this disclosure, while allowing sufficient transmission of light with wavelengths near the ultraviolet region. Therefore, by using the above-mentioned ultraviolet-transmitting dye, titanium black, or zirconium nitride as a coloring agent, and then using a photopolymerization initiator that has excellent reactivity to light at wavelengths in which the light transmittance of the above-mentioned ultraviolet-transmitting dye, titanium black, or zirconium nitride is high, the curable resin composition of this disclosure will have superior light-shielding properties, design properties, and photocurability.

[0067] The preferred lower limit for the content of the colorant in the curable resin composition of this disclosure is 0.1% by mass, and the preferred upper limit is 7% by mass. Having the colorant content within this range makes it easier to increase the optical density of the resulting curable resin composition. A more preferred lower limit for the colorant content is 0.3% by mass, and a more preferred upper limit is 5% by mass.

[0068] The curable resin composition of this disclosure may contain an antifoaming agent from the viewpoint of improving coatability, etc. Examples of the antifoaming agent include silicone-based antifoaming agents, acrylic polymer-based antifoaming agents, vinyl ether polymer-based antifoaming agents, olefin polymer-based antifoaming agents, and the like.

[0069] The curable resin compositions of this disclosure may further contain various known additives, such as plasticizers, silane coupling agents, sensitizers, thermosetting agents, curing retarders, antioxidants, storage stabilizers, and dispersants, to the extent that they do not impede the objectives of the present invention.

[0070] From the viewpoint of preventing a decrease in curability (reactivity), the curable resin composition of this disclosure preferably contains substantially no solvent, and more specifically, the solvent content in the curable resin composition is preferably 1.5% by mass or less. More preferably, the curable resin composition of this disclosure contains no solvent, and more specifically, the solvent content in the curable resin composition is 0% by mass. That is, the viscosity of the curable resin composition of this disclosure is preferably adjusted not by the solvent, but by the type and physical properties of the polymerizable compound represented by formula (1v) used.

[0071] A method for preparing the curable resin composition of this disclosure includes, for example, a method of mixing the polymerizable compound represented by the above formula (1v) with additives to be added as needed using a mixer (stirrer). Examples of such mixers include homodispersers, homomixers, universal mixers, planetary mixers, kneaders, and three-roll mixers.

[0072] The curable resin composition of this disclosure is preferably curable by at least one of light irradiation and / or heating, and more preferably curable by light irradiation.

[0073] A method for curing the curable resin composition of this disclosure by light irradiation includes, for example, a wavelength of 315 nm to 480 nm and an illuminance of 10 mW / cm². ２ More than 1000mW / cm ２ Examples of methods include irradiating with the following light for more than 10 seconds but less than 10 minutes.

[0074] Examples of light sources for irradiating the curable resin composition of this disclosure include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, excimer lasers, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, sodium lamps, halogen lamps, xenon lamps, LED lamps, fluorescent lamps, sunlight, electron beam irradiation devices, and the like. These light sources may be used individually or in combination of two or more types.

[0075] Examples of methods for irradiating the curable resin composition with light according to this disclosure include simultaneous irradiation with various light sources, sequential irradiation with time differences, and combined irradiation of simultaneous and sequential irradiation, and any of these irradiation methods may be used.

[0076] The curable resin composition of this disclosure can prevent the occurrence of liquid crystal contamination when used in liquid crystal display elements and damage to the organic light-emitting material layer when used in organic EL display elements. A encapsulant for display elements made from the curable resin composition of this disclosure is also one of the present inventions.

[0077] The sealing agent for display elements disclosed herein can be used as a sealing agent for sealing the entire surface, front, rear surface, or periphery of a display element, or as a sealing agent for sealing an opening provided in a display element, and is particularly suitable for sealing the entire surface of a display element. In this specification, "entire surface" does not necessarily mean 100% of the surface of the display element, but rather means the entire required sealing surface of the display element. Furthermore, "front surface" means the side from which light rays are extracted, i.e., the viewing side.

[0078] The encapsulant for display elements disclosed herein can be used, for example, in organic EL curable resin compositions, sealing agents for liquid crystal display elements, encapsulants for electrochromic substrates, encapsulants for electronic paper, and the like.

[0079] When the curable resin composition of this disclosure is used as a encapsulant for a display element, the preferred lower limit of the viscosity of the curable resin composition of this disclosure at 25°C, measured using an E-type viscometer at 10 rpm, is 100 mPa·s. A viscosity of 100 mPa·s or higher at 25°C of the curable resin composition makes it possible to dispense the curable resin composition with high precision. A more preferred lower limit of the viscosity of the curable resin composition of this disclosure at 25°C is 200 mPa·s.

[0080] A preferred upper limit for the viscosity of the curable resin composition of this disclosure at 25°C is 60,000 mPa·s. A viscosity of 60,000 mPa·s or less at 25°C allows for precise dispensing of the curable resin composition. A more preferred upper limit for the viscosity of the curable resin composition of this disclosure at 25°C is 50,000 mPa·s.

[0081] The viscosity of the curable resin composition at 25°C can be measured using an E-type viscometer (for example, the "VISCOMETER TV-22" manufactured by Toki Sangyo Co., Ltd.) with a No. 4 cone plate at 25°C and 10 rpm.

[0082] The viscosity of the curable resin composition at 25°C can be adjusted by changing the type and content of polymerizable compounds represented by formula (1v), the type and content of polymerizable compounds other than those represented by formula (1v), the type of polythiol compound, thickeners, fillers, etc.

[0083] The above curable resin composition is applied to a substrate to a thickness of 500 μm, and the illuminance is set to a wavelength of 365 nm and an illuminance of 100 mW / cm². ２ The preferred upper limit of the storage modulus at -20°C for the cured product obtained by irradiating it with light for 30 seconds is 500 MPa. Because the storage modulus at -20°C of the cured product is 500 MPa or less, the cured product has high bending resistance (flexibility) even when used in cold regions, making it suitable for use as a peripheral sealant for the casing of foldable smartphones and the like. A more preferred upper limit of the storage modulus at -20°C for the cured product is 300 MPa.

[0084] A preferred lower limit for the storage modulus of the cured product at -20°C is 0.1 MPa. A storage modulus of 0.1 MPa or higher at -20°C ensures the strength required for applications such as sealing agents for display elements. A more preferred lower limit for the storage modulus of the cured product at -20°C is 0.5 MPa.

[0085] The storage modulus of the cured product at -20°C can be measured by the following method. First, the curable resin composition is applied to a release PET film used as a base material. A 500 μm thick silicone rubber sheet is used to create a hole punched out in a shape of 5 mm wide and 45 mm long, so that the resin has a thickness of 500 μm. The top surface is then sealed with another release PET film and flattened by squeegees. After that, a light irradiation device is used to measure the resin at a wavelength of 365 nm and an illuminance of 100 mW / cm². ２ The curable resin composition is cured by irradiating it with light from the front side for 30 seconds, obtaining a cured product sandwiched between a pair of release PET films. If the curable resin composition contains a coloring agent, light is also irradiated from the back side at a wavelength of 365 nm and an illuminance of 100 mW / cm². ２ A cured product is obtained by irradiating it with light for 30 seconds. The two release PET films that sandwich the cured product are peeled off, and the dynamic viscoelastic spectrum of the obtained test piece is measured from -40 to 140°C using a viscoelastic spectrometer (e.g., DVA-200, manufactured by IT Measurement Control Co., Ltd.) under the conditions of constant-speed heating tensile mode at 10°C / min, strain of 0.1%, and frequency of 10 Hz. The storage modulus at -20°C obtained as a result is taken as the storage modulus at -20°C of the cured product.

[0086] The storage modulus of the cured product at -20°C can be adjusted by changing the type and content of polymerizable compounds represented by formula (1v), the type and content of polymerizable compounds other than those represented by formula (1v), the type of polythiol compound, fillers, etc.

[0087] The above curable resin composition is applied to a substrate to a thickness of 500 μm, and the illuminance is set to a wavelength of 365 nm and an illuminance of 100 mW / cm². ２ The preferred lower limit of the tensile elongation at 25°C for the cured product obtained by irradiating it with light for 30 seconds is 80%. Because the tensile elongation at 25°C of the cured product is 80% or higher, it has high bending resistance (flexibility), making it suitable for use as a peripheral sealant for the casings of foldable smartphones and the like. A more preferred lower limit for the tensile elongation at 25°C of the cured product is 90%. There is no particular preferred upper limit for the tensile elongation at 25°C of the above cured product, but the practical upper limit is 1000%.

[0088] The tensile elongation at 25°C of the cured material can be measured by the following method. First, the curable resin composition is applied to a release PET film used as a base material. A 500 μm thick silicone rubber sheet is used to create a hole punched out in a shape of 5 mm wide and 45 mm long, and the resin is applied to the recessed portion. The top surface is then sealed with another release PET film and flattened by squeegees. After that, a light irradiation device is used to measure the elongation at a wavelength of 365 nm and an illuminance of 100 mW / cm². ２ The curable resin composition is cured by irradiating it with light from the front side for 30 seconds, obtaining a cured product sandwiched between a pair of release PET films. If the curable resin composition contains a coloring agent, light is also irradiated from the back side at a wavelength of 365 nm and an illuminance of 100 mW / cm². ２ The material is irradiated with light for 30 seconds to obtain a cured product. The two release PET films holding the cured product are peeled off, and the resulting test piece is measured using a tensile testing machine (for example, Shimadzu Corporation's "Autograph AG-XPlus") under the conditions of 25°C, a grip distance of 25 mm, and a tensile speed of 10 mm / min. The resulting tensile elongation at 25°C is taken as the tensile elongation at 25°C for the cured product.

[0089] The tensile elongation at 25°C of the cured product can be adjusted by changing the type and content of polymerizable compounds represented by formula (1v), the type and content of polymerizable compounds other than those represented by formula (1v), the type of polythiol compound, fillers, etc.

[0090] A 500 μm thick rubber sheet is prepared with a 5 mm diameter through-hole, one side is sealed with tape, and the above-mentioned curable resin composition is filled into the hole. At a wavelength of 365 nm and an illuminance of 100 mW / cm², the test is performed. ２The preferred lower limit for the thickness of the cured product obtained by irradiating it with light for 30 seconds (hereinafter also simply referred to as "cured product formed using a 500 μm thick rubber sheet") is 200 μm. By having a thickness of 200 μm or more of the cured product formed using the 500 μm thick rubber sheet, the curable resin composition can form a cured product with excellent deep curing properties. The more preferred lower limit for the thickness of the cured product formed using the 500 μm thick rubber sheet is 400 μm. The upper limit for the thickness of the cured product formed using the 500 μm thick rubber sheet is 500 μm.

[0091] The thickness of a cured product formed using a 500 μm thick rubber sheet can be measured by the following method: A 5 mm diameter through-hole is made in the 500 μm thick rubber sheet, one side is sealed with tape, and the hole is filled with the respective curable resin composition. Then, using a light irradiation device, the thickness is measured at a wavelength of 365 nm and an irradiance of 100 mW / cm². ２ The curable resin composition is cured by irradiating it with light for 30 seconds to obtain a cured product. The cured product is removed and its thickness is measured using a micrometer (for example, Mitutoyo's "Soft Touch Micro CLM"). The resulting thickness is taken as the thickness of the cured product formed using a 500 μm thick rubber sheet.

[0092] The thickness (deep curing properties) of a cured product formed using a 500 μm thick rubber sheet can be adjusted by changing the type and content of polymerizable compounds represented by formula (1v), the type and content of polymerizable compounds other than those represented by formula (1v), the type of polythiol compound, fillers, etc.

[0093] The surface reactivity of the cured product can be measured by the following method. The curable resin composition is dropped onto the detection section of an FT-IR (e.g., "Nicolet iS5" from Thermo SCIENTIFIC, etc.), and the peak area of ​​the UV-reactive functional group, the allyl group or acrylic group (hereinafter also simply referred to as the "pre-reaction target peak area") and the peak area of ​​the reference (ester group) (hereinafter also simply referred to as the "reference peak area") are measured at 25°C. Next, the curable resin composition is poured onto a glass substrate (e.g., "Eagle XG" from AGC Fabretech, 700 μm thick) using a 500 μm thick rubber sheet, and the top surface is flattened by squeezing with glass or the like. Then, a light irradiation device (e.g., "UVS01-01" from CCS, etc.) is used to irradiate the surface at a wavelength of 365 nm and an irradiance of 100 mW / cm². ２ A resin cured product with a thickness of 500 μm is obtained by irradiating it with light for 30 seconds. Using an FT-IR (for example, "Nicolet iS5" manufactured by Thermo SCIENTIFIC) at 25°C, the peak area of ​​the UV-reactive functional group, the allyl group or acrylic group (hereinafter also simply referred to as the "post-reaction target peak area"), is measured for the above resin cured product. Finally, the surface reactivity of the cured product is calculated using the following formula (Fv).

[0094]

[0095] The surface reactivity of the above cured product can be adjusted by changing the type and content of the polymerizable compound represented by formula (1v), the type and content of the polythiol compound, the initiator, etc.

[0096] According to the present invention, it is possible to provide a polymerizable compound that exhibits excellent bending resistance of the cured product and suppresses surface tackiness of the cured product, a curable resin composition containing the polymerizable compound, and a encapsulant for display elements made from the curable resin composition.

[0097] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0098] (Synthesis Example 1: Synthesis of Urethane Allyl Av) 20.27 parts by mass of polytrimethylene ether glycol (SK CHEMICALS "ECOTRION H-2000", hydroxyl value 56.0 mg KOH / G) as the polyol was placed in a 500 ml separable flask, and 3.73 parts by mass of diphenylmethane diisocyanate (Nisso Shoji Co., Ltd. "PURE MDI") as the polyisocyanate was added. The mixture was stirred at 80°C for 3 hours and reacted. After the temperature rise stabilized, the reaction was increased to 100°C to obtain a urethane prepolymer. Subsequently, the temperature was lowered to 80°C, and 0.24 parts by mass of U-CAT 660M (Sun Apro Co., Ltd.) and 0.98 parts by mass of allyl glycol (Nippon Emulsifier Co., Ltd.) were added. The mixture was stirred for 3 hours and reacted to obtain urethane allyl Av with allylated ends.

[0099] From the types of reagents used in the synthesis of urethane allyl Av and the amounts of reagents added, urethane allyl Av has the structure represented by the above formula (1v), and R １ｖ and R ２ｖ is an ethylene group, a ｕ is a non-negative integer, and R ｖ It had a structure represented by the following formula (4v).

[0100]

[0101] In formula (4v), q ｖ is an integer greater than or equal to 1, and * represents a combination.

[0102] (Synthesis Examples 2-3: Synthesis of Urethane Allyl Bv and Cv) Urethane allyl Bv and Cv were synthesized in the same manner as in Synthesis Example 1, except that the type of polyol was changed from ECOTRION H-2000 to PTG-650SN (manufactured by Hodogaya Chemical Co., Ltd.) or used in combination. Urethane allyl Bv and Cv are R ｖ Aside from being different, it had a similar structure to urethane allyl Av.

[0103] Urethane allyl Bv is R ｖ All of these compounds had a structure represented by the following formula (3v-1). Urethane allyl Cv contained the total R in one molecule. ｖ some of R ｖThe structure is represented by the following formula (3v-1), and the remaining R ｖ The compound had the structure represented by the above formula (4v).

[0104]

[0105] In formula (3v-1), p ｖ is an integer greater than or equal to 1, and * represents a combination.

[0106] (Examples 1-10, Comparative Examples 1-4) Each material was mixed in a planetary agitator (Sinky Co., Ltd., "Awatori Rentaro") according to the mixing ratios (mass ratios) listed in Tables 1-2 to obtain the respective curable resin compositions of the Examples and Comparative Examples. Details of the materials indicated by abbreviations in the table are as follows.

[0107] <Polythiol Compounds> ・Karenz MT BD 1: 1,4-bis(3-mercaptobutyryloxy)butane (manufactured by Resonaq) ・Multihol Y-2: Trimethylolpropanedipropanthol (manufactured by Sakai Chemical Industry Co., Ltd.) ・Multihol Y-3: Pentaerythritoltripropanthol (manufactured by Sakai Chemical Industry Co., Ltd.) <Other Polyfunctional Polymerizable Compounds> ・TAIC: Triallyl isocyanurate (manufactured by Shinryo Co., Ltd., an allyl monomer having three polymerizable unsaturated double bonds in one molecule) ・Daiso Dap 100 monomer: Diallyl isophthalate monomer (DAIM, manufactured by Osaka Soda Co., Ltd., an allyl monomer having two polymerizable unsaturated double bonds in one molecule) ・Daiso Dap A: Diallyl phthalate resin (manufactured by Osaka Soda Co., Ltd., having two or more polymerizable unsaturated double bonds in one molecule)・CN8893: Aliphatic urethane acrylate (manufactured by Sartomer, an acrylate with two polymerizable unsaturated double bonds in one molecule) <Other monofunctional polymerizable compounds> ・Medol10: (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., an acrylate with one polymerizable unsaturated double bond in one molecule) ・Light acrylate PO-A: Phenoxyethyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd., an acrylate with one polymerizable unsaturated double bond in one molecule) ・SR440: Isooctyl acrylate (manufactured by Tomoe Industries Co., Ltd., an acrylate with one polymerizable unsaturated double bond in one molecule) <Non-polymerizable compounds>・Clarity LA2114: MMA / BA / MMA block polymer (where MMA represents the homopolymerization block unit of methyl methacrylate, and BA represents the homopolymerization block unit of n-butyl acrylate) (manufactured by Kuraray Co., Ltd.) <Polymerization initiator> ・Omnirad TPO-N: 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TPO-N, manufactured by IGM Resins B.V., photopolymerization initiator) <Coloring agent> ・13M-C: Titanium black (manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd., pigment) ・Elixa black 850: UV-permeable dye (manufactured by Orient Chemical Industry Co., Ltd.)

[0108] (Viscosity of curable resin composition at 25°C) 0.4 mL of the obtained curable resin composition was collected, and the viscosity was measured using an E-type viscometer (manufactured by Toki Sangyo Co., Ltd., "VISCOMETER TV-22") with a No. 4 cone plate under the conditions of 25°C and 10 rpm. The viscosity at 25°C was evaluated, with a case where the viscosity was 300 mPa·s or more rated as "A" and a case where the viscosity was less than 300 mPa·s rated as "B". The results are shown in Tables 1 to 2.

[0109] (Storage elastic modulus of cured product at -20°C) The obtained curable resin composition was applied into a recess with a punched hole of 5 mm width and 45 mm length formed on a release PET film as a substrate using a 500 μm-thick silicone rubber sheet so that the thickness of the composition would be 500 μm, the top surface was further sealed with a release PET film, and the composition was flattened by squeegeeing. Thereafter, using a light irradiation device (manufactured by CCS Inc., "UVS01-01"), at a wavelength of 365 nm and an illuminance of 100 mW / cm ２ light was irradiated from the front side for 30 seconds to cure the curable resin composition, thereby obtaining a cured product sandwiched between a pair of release PET films. For a black sample containing a colorant, light with a wavelength of 365 nm and an illuminance of 100 mW / cm ２ was further irradiated from the back side for 30 seconds. Both release PET films sandwiching the cured product were peeled off, and the obtained test piece was measured for dynamic viscoelastic spectrum from -40°C to 140°C using a viscoelastic spectrometer (manufactured by IT Keisoku Seigyo Co., Ltd., DVA-200) under the conditions of constant-speed heating tensile mode at 10°C / min, 0.1% strain, and 10 Hz frequency. The resulting storage elastic modulus at -20°C was taken as the storage elastic modulus of the cured product at -20°C. The storage elastic modulus at -20°C was evaluated, with a case where the storage elastic modulus at -20°C was 500 MPa or less rated as "A" and a case where the storage elastic modulus exceeded 500 MPa rated as "B". The results are shown in Tables 1 to 2.

[0110] (Tensile elongation at 25°C of cured material) The tensile elongation at 25°C was measured using a tensile testing machine (Shimadzu Corporation, "Autograph AG-XPlus") obtained in the same manner as described above for "(Storage modulus of cured material at -20°C)". The tensile elongation at 25°C was evaluated as follows: "A" if the tensile elongation at 25°C was 80% or more, and "B" if it was less than 80%. The results are shown in Tables 1 and 2.

[0111] (Surface tackiness of cured material) The curable resin composition was applied to a glass substrate (AGC Fabricech, "Eagle XG") to a thickness of 50 μm using 50 μm thick Kapton tape as a dam. Then, the top surface was squeegeeed with glass, and with the coated surface exposed to air, a light irradiation device (CCS, "UVS01-01") was used to irradiate it at a wavelength of 365 nm and an irradiance of 100 mW / cm². ２ The curable resin composition was cured by irradiating it with light for 30 seconds to obtain a cured product. Tackiness was evaluated using Rhesca's "TAC-II" under the following conditions: probe diameter Φ5 mm, indentation speed 120 mm / min, release speed 5 mm / min, indentation pressure 200 gf, and indentation time 5 s. 300 gf / cm ２ If the following conditions are met, it will be classified as "A", 300 gf / cm². ２ The surface tackiness of the cured product was evaluated, with values ​​exceeding a certain threshold designated as "B". The results are shown in Tables 1 and 2. It should be noted that curable resin compositions with a surface tackiness rating of A have higher reactivity of the polymerizable compounds contained in the composition than curable resin compositions with a rating of B.

[0112] (Deep curing properties of the cured material) A 500 μm thick rubber sheet was prepared with a 5 mm diameter through-hole, and one side was sealed with tape. Each curable resin composition was then filled into the hole. Next, a light irradiation device (CCS Corporation, "UVS01-01") was used to irradiate the material at a wavelength of 365 nm and an irradiance of 100 mW / cm². ２A cured product was obtained by irradiating with light for 30 seconds. Thereafter, the cured product was taken out, and the thickness of the cured product was measured with a micrometer ("Soft Touch Micro CLM" manufactured by Mitutoyo Corporation). Deep-section curability was evaluated, where a case where the thickness of the cured product was 200 µm or more was rated "A", and a case where the thickness was less than 200 µm was rated "B". The results are shown in Tables 1 to 2. It should be noted that a curable resin composition whose cured product has deep-section curability rated A can be said to have higher reactivity of the polymerizable compound contained in the composition than a curable resin composition rated B.

[0113] (Surface Reactivity of Cured Product) The obtained curable resin composition was dropped onto the detection unit of an FT-IR ("Nicolet iS5" manufactured by Thermo SCIENTIFIC), and under the condition of 25°C, the allyl group, which is an ultraviolet-reactive functional group (940 to 1000 cm －１ ) or acrylic group (800 to 840 cm －１ ) peak area (hereinafter sometimes simply referred to as "pre-reaction target peak area") and the peak area of the reference (ester group (1600 to 1850 cm －１ )) (hereinafter sometimes simply referred to as "reference peak area") were measured. Next, the curable resin composition was poured onto a glass substrate ("Eagle XG" manufactured by AGC Fabritech, thickness 700 µm) using a rubber sheet with a thickness of 500 µm, the upper surface was flattened by squeegeeing with glass or the like, and using a light irradiation device ("UVS01-01" manufactured by CCS Inc.), wavelength 365 nm, illuminance 100 mW / cm ２ A cured resin product with a thickness of 500 µm was obtained by irradiating the light for 30 seconds. Using FT-IR ("Nicolet iS5" manufactured by Thermo SCIENTIFIC) under the condition of 25°C, the peak area of the allyl group or acrylic group, which is an ultraviolet-reactive functional group (hereinafter sometimes simply referred to as "post-reaction target peak area"), was measured for the above cured resin product. Finally, the surface reactivity of the cured product was calculated using the above formula (Fv). The surface reactivity was evaluated, where a case where the surface reactivity was 85% or more was rated "A", and a case where the surface reactivity was less than 85% was rated "B". The results are shown in Tables 1 to 2.

[0114]

[0115]

[0116] The cured products of the curable resin compositions in Examples 6 and 7 also exhibited light-shielding properties.

[0117] According to the present invention, it is possible to provide a polymerizable compound that exhibits excellent bending resistance of the cured product and suppresses surface tackiness of the cured product, a curable resin composition containing the polymerizable compound, and a encapsulant for display elements made from the curable resin composition.

Claims

1. A polymerizable compound characterized by being represented by the following formula (1v). In formula (1v), a ｖ represents a non-negative integer, R ｖ Each of these independently represents an organic group having 2 to 10 carbon atoms, and at least one R ｖ It has an alkylene glycol skeleton in which the number of repeating alkylene units having 2 to 6 carbon atoms is 1 or more, R １ｖ and R ２ｖ Each of these independently represents an organic group with 2 to 10 carbon atoms.

2. In the above formula (1v), R ｖ The polymerizable compound according to claim 1, wherein the number of carbon atoms in the alkylene unit contained in the alkylene glycol skeleton is 3 or 4.

3. In the above formula (1v), at least one R ｖ The polymerizable compound according to claim 1, having a structure represented by the following formula (2v). In equation (2v), * represents a coupling.

4. The polymerizable compound according to claim 1, wherein in the formula (1v), at least one R ｖ has a structure represented by the following formula (3v). In the formula (3v), * represents a bonding site, and k ｖ represents 1 or 2, m ｖ represents 0, 1 or 2, n ｖ represents 0, 1 or 2, and both of m ｖ and n ｖ are not 0 at the same time.

5. A curable resin composition characterized by containing the polymerizable compound described in any one of claims 1 to 4.

6. The curable resin composition according to claim 5, further comprising a polythiol compound having multiple thiol groups in one molecule and a polymerization initiator.

7. The curable resin composition is applied to the substrate to a thickness of 500 μm, and exposed to light at a wavelength of 365 nm and an illuminance of 100 mW / cm². ２ The curable resin composition according to claim 5, wherein the storage modulus of the cured product obtained by irradiating with light for 30 seconds is 500 MPa or less at -20°C.

8. A encapsulant for a display element, characterized by comprising the curable resin composition described in claim 5.

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