Sealing agent for display elements

Abstract

An object of the present application is to provide a sealing agent for a display element which is excellent in both adhesiveness and moisture permeation resistance. The present application is a sealing agent for a display element, which contains a curable resin and a polymerization initiator, the aforementioned curable resin including at least one selected from the group consisting of a compound represented by the following formula (I) and a compound represented by the following formula (II). In formula (I) and formula (II), R 1 represents a hydrogen atom or a methyl group, R 2 represents a structure derived from an optionally substituted dicarboxylic acid or an anhydride thereof, X represents an open ring structure of a lactone, n is 0 or more and 2.0 or less (average value), Y represents an optionally substituted aliphatic cyclic structure, and Ep represents a structure derived from a di-functional or more epoxy compound.

Description

Technical Field

[0001] This invention relates to sealants for display elements. Background Technology

[0002] In recent years, liquid crystal display (LCD) elements and organic EL display elements have been widely used as display components with characteristics such as thinness, light weight, and low power consumption. In such display elements, sealants are typically used for bonding various components and sealing the liquid crystal or light-emitting layer.

[0003] For example, as a manufacturing method for liquid crystal display elements, from the viewpoint of shortening cycle time and optimizing the amount of liquid crystal used, a liquid crystal dispensing process, known as the dispensing process, is used, which employs a sealant for display elements as disclosed in Patent Documents 1 and 2. In the dispensing process, firstly, a sealant for display elements is applied to one of two electrode-bearing substrates to form a frame-shaped sealing pattern. Then, while the sealant is not yet cured, tiny droplets of liquid crystal are dispensed into the sealing frame of the substrate. Under vacuum, the other substrate is overlapped to cure the sealant, thus fabricating the liquid crystal display element. Currently, this dispensing process has become the mainstream manufacturing method for liquid crystal display elements.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2001-133794

[0007] Patent Document 2: International Publication No. 02 / 092718 Summary of the Invention

[0008] The problem the invention aims to solve

[0009] With the increasing prevalence of tablet computers and portable devices, display components are facing growing demands for moisture resistance reliability under high temperature and humidity conditions, further requiring sealants to prevent water ingress. To improve the moisture resistance reliability of display components and prevent water from penetrating the interface between the sealant and the substrate, it is necessary to improve both the sealant's adhesion to the substrate and its moisture-proof properties. One method to improve the moisture-proof properties of sealants is to incorporate fillers such as talc; however, under rigorous moisture resistance reliability testing, uneven display sometimes occurs within the display component. Especially in the case of display components with narrow bezel designs, even sealants that have previously been reliable struggle to simultaneously achieve both adhesion (particularly the adhesion of sealants for liquid crystal display components to the alignment film) and moisture-proof properties.

[0010] The object of this invention is to provide a sealant for display elements that has excellent adhesion and moisture-proof properties.

[0011] Solution for solving the problem

[0012] This disclosure 1 is a sealant for display elements, comprising a curable resin and a polymerization initiator, wherein the curable resin comprises at least one selected from the group consisting of compounds represented by formula (I) and compounds represented by formula (II).

[0013] This disclosure 2 is a sealant for a display element according to this disclosure 1, wherein the curable resin contains a compound represented by the following formula (1) as the compound represented by the above formula (I).

[0014] This disclosure 3 is a sealant for a display element according to disclosure 1 or 2, wherein, in the following formula (I) and the following formula (II), R 2 It is the structure shown in equations (2-1), (2-2), (2-3), or (2-4).

[0015] This disclosure 4 is a sealant for display elements according to disclosure 1, 2 or 3, wherein, in formula (I) and formula (II) below, R 2 It is the structure shown in equations (3-1), (3-2), (3-3), or (3-4).

[0016] This disclosure 5 is a sealant for a display element according to disclosure 1, 2, 3 or 4, wherein the total content of the compound represented by formula (I) and the compound represented by formula (II) in 100 parts by mass of the curable resin is 5 parts by mass or more and 60 parts by mass or less.

[0017] This disclosure 6 is a sealant for a display element according to disclosure 1, 2, 3, 4 or 5, wherein the curable resin further comprises a bisphenol type epoxy compound, and the total content of the compound shown in formula (I) and the compound shown in formula (II) is 50 parts by mass or more and 600 parts by mass or less relative to 100 parts by mass of the bisphenol type epoxy compound.

[0018] This disclosure 7 is a sealant for display elements according to disclosures 1, 2, 3, 4, 5 or 6, used to manufacture liquid crystal display elements by liquid crystal dispensing process.

[0019]

[0020] In equations (I) and (II), R 1 R represents a hydrogen atom or a methyl group. 2 The structure is derived from an optionally substituted dicarboxylic acid or its anhydride, X represents the open ring structure of a lactone, n is 0 or more and 2.0 or less (average), Y represents the optionally substituted aliphatic cyclic structure, and Ep represents the structure derived from a difunctional or higher epoxide compound.

[0021]

[0022] In equation (1), R 1 R represents a hydrogen atom or a methyl group. 2 The structure is derived from an optional substituted dicarboxylic acid or its anhydride, X represents the open ring structure of a lactone, n is 0 or more and 2.0 or less (average), and Ep represents the structure derived from a more or less difunctional epoxide.

[0023] In formula (1), both 1,4-cyclohexyl groups are optionally partially or completely substituted with hydrogen atoms.

[0024]

[0025] In equations (2-1) to (2-4), * represents the bonding position. In equation (2-1), R 3 ~R 12 Each of the following independently represents an alkyl group having 1 or more but less than 10 hydrogen atoms, in formula (2-2), R 13 ~R 20 Each of the following independently represents an alkyl group having 1 or more but less than 10 hydrogen atoms, in formula (2-3), R 21 ~R 24 Each of the following independently represents an alkyl group having 1 or more but less than 10 carbon atoms, in formula (2-4), R 25 ~R 28 Each can independently represent an organic group having 1 or more hydrogen atoms and 60 or fewer carbon atoms, or, represent R 25 With R 28 Each is independently an alkyl group having 1 or more but less than 10 carbon atoms, and R 26 With R 27 Bonded structure.

[0026]

[0027] In equations (3-1) to (3-4), * represents the bonding position. In equation (3-1), R 29 Represents an alkyl group having 1 or more hydrogen atoms and less than 10 carbon atoms, in formula (3-2), R 30 Represents an alkyl group having 1 or more hydrogen atoms and less than 10 carbon atoms, in formula (3-3), R 31 Represents an alkyl group having 1 or more hydrogen atoms and less than 10 carbon atoms, in formula (3-4), R 32 and R 33 Each can independently represent an organic group having 1 or more hydrogen atoms and 60 or fewer carbon atoms, or represent R. 32 With R 33 Bonded structure.

[0028] The present invention will be described in detail below.

[0029] The inventors investigated how using a soft resin with long molecular chains as the curing resin in a sealant for display elements imparts flexibility and stress relaxation properties to the sealant, thereby ensuring high adhesion. However, in narrow bezel designs where the sealant is applied in finer lines, adhesion sometimes becomes insufficient, leading to delamination from the substrate of the display element. The inventors investigated methods to improve adhesion by using a soft resin with even longer molecular chains, but the resulting sealant exhibited poor moisture impermeability, sometimes resulting in display defects when the manufactured display element is exposed to high temperature and humidity environments. Therefore, the inventors conducted further in-depth research and discovered that by using a compound with a specific structure as the curing resin, a sealant for display elements with excellent adhesion and moisture impermeability can be obtained, thus completing the present invention.

[0030] The sealant for display elements of the present invention contains a curable resin.

[0031] The curable resin described above comprises at least one selected from the group consisting of the compound shown in formula (I) and the compound shown in formula (II). By containing at least one selected from the group consisting of the compound shown in formula (I) and the compound shown in formula (II), the sealant for display elements of the present invention exhibits excellent adhesion (particularly adhesion to the alignment film) and moisture impermeability. Furthermore, when used as a sealant for liquid crystal display elements, it also exhibits excellent low liquid crystal contamination. Preferably, the curable resin comprises the compound shown in formula (I), and more preferably comprises the compound shown in formula (I) as the compound shown in formula (I).

[0032] In equations (I) and (II) above, R 2 This indicates a structure derived from an optionally substituted dicarboxylic acid or its anhydride. By making the above R... 2 The structure is derived from a dicarboxylic acid or its anhydride that is optionally substituted, thus the adhesive properties of the resulting display element with the sealant (especially the adhesive properties relative to the alignment film) become excellent.

[0033] The optional substituted dicarboxylic acid can be either aliphatic or aromatic.

[0034] In addition, examples of substituents used when the aforementioned optional dicarboxylic acid or its anhydride is substituted include, for example, carbon chains containing an aromatic ring and having an optional unsaturated bond and branched structure with 1 to 60 carbon atoms; hydrocarbon skeletons containing cyclic structures, etc.

[0035] As optional substituted dicarboxylic acids or their anhydrides, examples include, for instance: phthalic anhydride, 3-methylphthalic anhydride, 4-methylphthalic anhydride, 4-tert-butylphthalic anhydride, 1,2-naphthalenedicarboxylic anhydride, 2,3-naphthalenedicarboxylic anhydride, 1,8-naphthalenedicarboxylic anhydride, phenylmaleic anhydride, phenylsuccinic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 3-methylcyclohexane-1,2-dicarboxylic anhydride, 4-methylcyclohexane-1,2-dicarboxylic anhydride, 4-cyclohexene-1,2-dicarboxylic anhydride, 3-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, 3,4,5,6-tetrahydrophthalic anhydride, 4-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, tetrapropylene succinic anhydride, and decanoic anhydride. alkyl succinic anhydride, tetradecyl succinic anhydride, tetradecenyl succinic anhydride, hexadecyl succinic anhydride, allyl succinic anhydride, isooctadecenyl succinic anhydride, butyl succinic anhydride, 4-hexene-1,2-dicarboxylic anhydride, 2-dodecen-1-yl succinic anhydride, 2,2-dimethyl succinic anhydride, 2-hexene-1-yl succinic anhydride, 4-methyl-4-penten-1,2-dicarboxylic anhydride, 2-octenyl succinic anhydride, 4,9-decadien-1,2-dicarboxylic anhydride, bicyclo[2.2.2]oct-5-en-2,3-dicarboxylic anhydride, 2-(2-carboxyethyl)-3-methylmaleic anhydride, 7-oxabicyclo[2.2.1]hept-5-en-2,3-dicarboxylic anhydride and their anhydride-pre-anhydride dicarboxylic acids, etc.

[0036] From the viewpoint of further improving the adhesion of the sealant for the obtained display element (especially the adhesion relative to the alignment film), the above-mentioned R 2 Preferably, the structure is shown in formula (2-1), (2-2), (2-3) or (2-4) above, and more preferably, the structure is shown in formula (3-1), (3-2), (3-3) or (3-4) above.

[0037] As the structure shown in formula (2-1) above, for example, structures derived from 1,2-cyclohexanedicarboxylic anhydride, 3-methylcyclohexane-1,2-dicarboxylic anhydride, 4-methylcyclohexane-1,2-dicarboxylic anhydride, etc., can be cited.

[0038] Examples of structures derived from 4-cyclohexene-1,2-dicarboxylic anhydride, 3-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, 3,4,5,6-tetrahydrophthalic anhydride, and 4-methyl-4-cyclohexene-1,2-dicarboxylic anhydride can be cited as structures represented by formula (2-2) above.

[0039] As the structure shown in formula (2-3) above, for example, structures derived from phthalic anhydride, 3-methylphthalic anhydride, 4-methylphthalic anhydride, 4-tert-butylphthalic anhydride, etc. can be cited.

[0040] As shown in equation (2-4) above, it can be R 26 With R 27 Unbonded structures can also be R 26 With R 27 From the perspective of improving moisture resistance, the bonded structure preferably uses R. 26 With R 27 Bonded structure.

[0041] As mentioned above, R 26 With R 27 Unbonded structures, for example, can be derived from tetrapropylene succinic anhydride, decyl succinic anhydride, tetradecyl succinic anhydride, tetradecenyl succinic anhydride, hexadecyl succinic anhydride, isooctadecenyl succinic anhydride, butyl succinic anhydride, allyl succinic anhydride, 4-hexen-1,2-dicarboxylic anhydride, 2-dodecen-1-yl succinic anhydride, 2,2-dimethyl succinic anhydride, 2-hexen-1-yl succinic anhydride, 4-methyl-4-penten-1,2-dicarboxylic anhydride, 2-octenyl succinic anhydride, 4,9-decadien-1,2-dicarboxylic anhydride, etc.

[0042] As mentioned above, R 26 With R 27 Examples of bonded structures include those derived from 5-norbornene-2,3-dicarboxylic anhydride, bicyclo[2.2.2]oct-5-ene-2,3-dicarboxylic anhydride, and 7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride.

[0043] In formulas (I) and (II) above, X represents the open-ring structure of the lactone.

[0044] Examples of the aforementioned lactones include γ-undecylactone, ε-caprolactone, γ-decylactone, σ-dodecylactone, γ-nonanolactone, γ-heptanolactone, γ-pentanolactone, σ-pentanolactone, β-butyrolactone, γ-butyrolactone, β-propiolactone, σ-caprolactone, and ε-decylactone. Among these, lactones in which the linear portion of the main skeleton has 5 or more but less than 7 carbon atoms when the ring is opened are preferred.

[0045] It should be noted that in formulas (I) and (II) above, when n is 0, i.e., when the open-ring structure of the lactone shown in X is absent, the moisture-proof properties of the resulting sealant for display elements are more excellent. When n is greater than 0 and less than 2.0 (average value), the adhesive properties of the resulting sealant for display elements (especially the adhesive properties relative to the alignment film) are more excellent. When n is greater than 0, it is preferable that n is greater than 0 and less than 0.5 (average value). Furthermore, the "average value" in n refers to the average value (molar average value) of the number of repetitions of compounds shown in formula (I) and formula (II) respectively, when they are mixtures of compounds with different numbers of repetitions of X.

[0046] In formulas (I) and (II) above, Ep represents a structure derived from an epoxy compound with two or more functions.

[0047] Examples of epoxy compounds that can be sources of the aforementioned Ep include: bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol E type epoxy compounds, bisphenol S type epoxy compounds, hydrogenated bisphenol A type epoxy compounds, hydrogenated bisphenol F type epoxy compounds, hydrogenated bisphenol E type epoxy compounds, hydrogenated bisphenol S type epoxy compounds, dicyclopentadiene type epoxy compounds, resorcinol type epoxy compounds, naphthalene type epoxy compounds, fluorene type epoxy compounds, rubber-modified epoxy compounds, glycidyl ester compounds, etc.

[0048] The Ep is preferably derived from the structure of a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, or a bisphenol E type epoxy compound.

[0049] It should be noted that, in this specification, the "structure derived from epoxy compounds" refers to the structure of the portion of the epoxy compound other than the epoxy groups.

[0050] The preferred upper limit of the molecular weight of the epoxy compound that forms the source of the aforementioned Ep is 1000. By keeping the molecular weight of the aforementioned epoxy compound below 1000, the operability of the resulting sealant for display elements becomes more excellent. A more preferred upper limit of the molecular weight of the epoxy compound that forms the source of the aforementioned Ep is 500.

[0051] In formulas (I) and (II) above, Y represents an optionally substituted aliphatic cyclic structure. By making Y such an aliphatic cyclic structure, both the adhesiveness (particularly the adhesiveness with respect to the alignment film) and the moisture-proof properties of the sealant for display elements of the present invention become excellent. Preferably, Y is substituted with 1,2-cyclohexylene, substituted with 1,3-cyclohexylene, or substituted with 1,4-cyclohexylene, and more preferably with substituted 1,4-cyclohexylene, particularly from the perspective of improving adhesiveness (particularly the adhesiveness with respect to the alignment film).

[0052] Furthermore, from the viewpoint of ease of obtaining raw materials, it is preferable that Y is not substituted. Examples of substituents that could be used to substitute Y include alkyl groups having 1 or more but less than 10 carbon atoms.

[0053] That is, in the above formula (1), some or all of the hydrogen atoms of the two 1,4-cyclohexene groups can be substituted, but from the viewpoint of ease of obtaining raw materials, it is preferable that they are not substituted. As a substituent when the hydrogen atoms of the two 1,4-cyclohexene groups in the above formula (1) are substituted, examples include alkyl groups with 1 or more and 10 or less carbon atoms.

[0054] As a method for manufacturing the compound shown in formula (I) above, the following methods can be cited as examples.

[0055] That is, examples include methods having the following steps: a step of reacting a compound having an aliphatic cyclic structure and (meth)acryloyloxymethyl and hydroxymethyl respectively bonded to the aliphatic cyclic structure, or a compound in which some or all of the hydrogen atoms of the aliphatic cyclic structure are substituted, with the aforementioned optionally substituted dicarboxylic acid or its anhydride in the presence of a polymerization inhibitor, by heating and stirring; and a step of reacting all epoxy groups by adding the aforementioned difunctional or higher epoxy compound to the obtained reactants and heating and stirring.

[0056] In particular, as a method for manufacturing the compound shown in the above formula (1), the following methods can be cited as examples.

[0057] That is, examples include methods having the following steps: a step of reacting 1,4-cyclohexanediethanol mono(meth)acrylate or a compound in which some or all of the hydrogen atoms of the cyclohexene group are substituted with the aforementioned optionally substituted dicarboxylic acid or its anhydride by heating and stirring in the presence of a polymerization inhibitor; and a step of reacting all epoxy groups by adding the aforementioned difunctional or higher epoxy compound to the obtained reactants and heating and stirring.

[0058] The above-mentioned 1,4-cyclohexanediethanol mono(meth)acrylate or compounds in which some or all of the hydrogen atoms of the cyclohexene group are substituted may be reacted with the above-mentioned lactone before reacting with the optional substituted dicarboxylic acid or its anhydride.

[0059] It should be noted that in this specification, "(meth)acryloyl" refers to acryloyl or methacryloyl, and "(meth)acrylate" refers to acrylate or methacrylate.

[0060] As a method for manufacturing the compound shown in formula (II) above, the following methods can be cited as examples.

[0061] That is, examples include methods having the following steps: a step of reacting a compound having an aliphatic cyclic structure and (meth)acryloyloxymethyl and hydroxymethyl respectively bonded to the aliphatic cyclic structure, or a compound in which some or all of the hydrogen atoms of the aliphatic cyclic structure are substituted, with the aforementioned optionally substituted dicarboxylic acid or its anhydride in the presence of a polymerization inhibitor, by heating and stirring; and a step of reacting a portion of the epoxy groups by adding the aforementioned difunctional or higher epoxy compound to the obtained reactants and heating and stirring.

[0062] Examples of polymerization inhibitors mentioned above include hydroquinone and p-methoxyphenol.

[0063] In addition to containing at least one of the compounds selected from the group consisting of the compounds shown in formula (I) and the compounds shown in formula (II), the above-mentioned curable resin preferably also contains other curable resins.

[0064] When the curable resin contains the other curable resins mentioned above, the preferred lower limit for the total content of the compound shown in formula (I) and the compound shown in formula (II) in 100 parts by mass of the curable resin is 5 parts by mass, and the preferred upper limit is 60 parts by mass. By making the total content of the compound shown in formula (I) and the compound shown in formula (II) 5 parts by mass or more, the adhesiveness (especially the adhesiveness relative to the alignment film) of the resulting sealant for display elements becomes more excellent. By making the total content of the compound shown in formula (I) and the compound shown in formula (II) 60 parts by mass or less, the moisture-proofness and operability of the resulting sealant for display elements become more excellent. The more preferred lower limit for the total content of the compound shown in formula (I) and the compound shown in formula (II) is 10 parts by mass, and the more preferred upper limit is 30 parts by mass.

[0065] It should be noted that in this specification, the term "total content of the compound shown in formula (I) and the compound shown in formula (II)" refers to the content of only one of these compounds when only one of them is contained, and to the total content when both are contained.

[0066] The aforementioned curable resin preferably includes a bisphenol-type epoxy compound as one of the other curable resins. By including the aforementioned bisphenol-type epoxy compound, the adhesiveness of the resulting sealant for display elements becomes more excellent.

[0067] Examples of bisphenol-type epoxy compounds include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol E type epoxy compounds, bisphenol S type epoxy compounds, and 2,2'-diallylbisphenol A type epoxy compounds.

[0068] In addition, as the aforementioned bisphenol-type epoxy compounds, partially (meth)acrylic acid-modified bisphenol-type epoxy compounds can be used.

[0069] Examples of partially (meth)acrylic acid-modified bisphenol-type epoxy compounds include partially (meth)acrylic acid-modified bisphenol A-type epoxy compounds, partially (meth)acrylic acid-modified bisphenol F-type epoxy compounds, and partially (meth)acrylic acid-modified bisphenol E-type epoxy compounds.

[0070] It should be noted that in this specification, "(meth)acrylic acid" refers to acrylic acid or methacrylic acid. Furthermore, in this specification, "partially (meth)acrylic acid modified epoxy compound" refers to a compound obtained by reacting a portion of the epoxy groups of an epoxy compound having two or more epoxy groups in one molecule with (meth)acrylic acid, resulting in a compound having one or more epoxy groups and one or more (meth)acryloyl groups in one molecule.

[0071] The preferred lower limit for the content of the bisphenol-type epoxy compound in 100 parts by weight of the curable resin is 5 parts by weight, and the preferred upper limit is 30 parts by weight. By setting the content of the bisphenol-type epoxy compound within this range, the adhesiveness of the resulting sealant for display elements becomes more excellent, and when used as a sealant for liquid crystal display elements, the low liquid crystal contamination also becomes excellent. The more preferred lower limit for the content of the bisphenol-type epoxy compound is 10 parts by weight, and the more preferred upper limit is 20 parts by weight.

[0072] The preferred lower limit for the total content of the compounds shown in Formula (I) and Formula (II) relative to 100 parts by mass of the bisphenol-type epoxy compound is 50 parts by mass, and the preferred upper limit is 600 parts by mass. By making the total content of the compounds shown in Formula (I) and Formula (II) relative to 100 parts by mass of the bisphenol-type epoxy compound 50 parts by mass or more, the adhesiveness (especially the adhesiveness relative to the alignment film) of the resulting sealant for display elements becomes more excellent. By making the total content of the compounds shown in Formula (I) and Formula (II) relative to 100 parts by mass of the bisphenol-type epoxy compound 600 parts by mass or less, the moisture-proofness and operability of the resulting sealant for display elements become more excellent. The preferred lower limit for the total content of the compounds shown in Formula (I) and Formula (II) relative to 100 parts by mass of the bisphenol-type epoxy compound is 100 parts by mass, and the preferred upper limit is 300 parts by mass.

[0073] Without hindering the purpose of the present invention, the above-mentioned curable resin may also contain curable resins other than the above-mentioned bisphenol type epoxy compounds as the other curable resins.

[0074] Examples of other curable resins besides the bisphenol type epoxy compounds mentioned above include: other (meth)acrylic compounds besides the compound shown in formula (I); other epoxy compounds besides the compound shown in formula (II) and the bisphenol type epoxy compounds mentioned above.

[0075] Examples of other (meth)acrylic acid compounds mentioned above include (meth)acrylate compounds, epoxy (meth)acrylates, and urethane (meth)acrylates. Among these, epoxy (meth)acrylates are preferred. Furthermore, from a reactivity point of view, the other (meth)acrylic acid compounds mentioned above preferably have two or more (meth)acryloyl groups in one molecule.

[0076] It should be noted that in this specification, "epoxy (meth)acrylate" refers to a compound obtained by reacting all the epoxy groups in an epoxy compound with (meth)acrylic acid.

[0077] Examples of monofunctional compounds among the aforementioned (meth)acrylate compounds include: methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, isononyl methacrylate, isodecanyl methacrylate, lauryl methacrylate, isomyristyl methacrylate, stearyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, dicyclopentenyl methacrylate, benzyl methacrylate, 2-methoxyethyl methacrylate, and 2-ethoxyethyl methacrylate. Esters, 2-butoxyethyl methacrylate, 2-phenoxyethyl methacrylate, methoxyethylene glycol (meth)acrylate, methoxy polyethylene glycol (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, tetrahydrofurfuryl methacrylate, ethyl carbitol (meth)acrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 1H,1H,5H-octafluoropentyl methacrylate, imide (meth)acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, 2-(meth)acryloyloxyethyl succinate, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxyethyl phthalate, 2-hydroxypropyl phthalate, 2-(meth)acryloyloxyethyl phosphate, glycidyl methacrylate, etc.

[0078] Furthermore, examples of difunctional (meth)acrylate compounds include: 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate. Polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene oxide addition bisphenol A di(meth)acrylate, propylene oxide addition bisphenol A di(meth)acrylate, ethylene oxide addition bisphenol F di(meth)acrylate, dihydroxymethyldicyclopentadienyl di(meth)acrylate, ethylene oxide modified isocyanuric acid di(meth)acrylate, 2-hydroxy-3-(meth)acryloyloxypropyl (meth)acrylate, carbonate glycol di(meth)acrylate, polyether glycol di(meth)acrylate, polyester glycol di(meth)acrylate, polycaprolactone glycol di(meth)acrylate, polybutadiene glycol di(meth)acrylate, etc.

[0079] In addition, examples of the above-mentioned (meth)acrylate compounds that are trifunctional or more include: trimethylolpropane tri(meth)acrylate, ethylene oxide addition trimethylolpropane tri(meth)acrylate, propylene oxide addition trimethylolpropane tri(meth)acrylate, caprolactone-modified trimethylolpropane tri(meth)acrylate, ethylene oxide addition isocyanuric acid tri(meth)acrylate, glycerol tri(meth)acrylate, propylene oxide addition glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tri(meth)acryloyloxyethyl phosphate, bis(trimethylolpropane)tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc.

[0080] Examples of epoxy (meth)acrylates include those obtained by reacting an epoxy compound with (meth)acrylic acid in the presence of a basic catalyst using conventional methods.

[0081] The epoxy compound used as a raw material for synthesizing the above-mentioned epoxy (meth)acrylate can be the same substance as the epoxy compound that is the source of the above-mentioned Ep.

[0082] Commercially available examples of the aforementioned epoxy (meth)acrylates include those manufactured by DAICEL-ALLNEX LTD., Shin-Nakamura Chemical Industry Co., Ltd., Kyoeisha Chemical Co., Ltd., and Nagase ChemteX Corporation.

[0083] Examples of epoxy (meth)acrylates manufactured by DAICEL-ALLNEX LTD. include EBECRYL860, EBECRYL3200, EBECRYL3201, EBECRYL3412, EBECRYL3600, EBECRYL3700, EBECRYL3701, EBECRYL3702, EBECRYL3703, EBECRYL3708, EBECRYL3800, EBECRYL6040, EBECRYL RDX63182, and KRM8076.

[0084] Examples of epoxy (meth)acrylates manufactured by Shin-Nakamura Chemical Industry Co., Ltd. include EA-1010, EA-1020, EA-5323, EA-5520, EA-CHD, and EMA-1020.

[0085] Examples of epoxy (meth)acrylates manufactured by Kyoei Chemical Co., Ltd. include: EPOXYESTER M-600A, EPOXYESTER 40EM, EPOXYESTER 70PA, EPOXYESTER 200PA, EPOXYESTER 80MFA, EPOXYESTER 3002M, EPOXYESTER 3002A, EPOXYESTER 1600A, EPOXYESTER 3000M, EPOXYESTER 3000A, EPOXYESTER 200EA, EPOXYESTER 400EA, etc.

[0086] Examples of epoxy (meth)acrylates manufactured by Nagase ChemteX Corporation include DENACOL ACRYLATE DA-141, DENACOL ACRYLATE DA-314, and DENACOL ACRYLATE DA-911.

[0087] The aforementioned urethane (meth)acrylates can be obtained, for example, by reacting a hydroxyl-containing (meth)acrylate derivative with an isocyanate compound in the presence of a catalytic amount of a tin-based compound.

[0088] Examples of the aforementioned isocyanate compounds include: isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4,4'-diisocyanate (MDI), hydrogenated MDI, polymerized MDI, 1,5-naphthalene diisocyanate, norbornene diisocyanate, bitoluidine diisocyanate, phenylmethylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, triphenyl thiophosphate triphenyl isocyanate, tetramethylphenylmethylene diisocyanate, and 1,6,11-undecane triisocyanate.

[0089] Alternatively, chain-extended isocyanate compounds obtained by reacting a polyol with an excess of the isocyanate compound can also be used as the aforementioned isocyanate compound.

[0090] Examples of such polyols include ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate glycol, polyether glycol, polyester glycol, and polycaprolactone glycol.

[0091] Examples of hydroxyl-containing (meth)acrylic acid derivatives include mono(meth)acrylic acid hydroxyalkyl esters, mono(meth)acrylic acid esters of diols, mono(meth)acrylic acid esters or di(meth)acrylic acid esters of triols, epoxy (meth)acrylic acid esters, etc.

[0092] Examples of the above-mentioned mono(meth)acrylate hydroxyalkyl esters include 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, and 4-hydroxybutyl methacrylate.

[0093] Examples of the aforementioned diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and polyethylene glycol.

[0094] Examples of the aforementioned triols include trimethylolethane, trimethylolpropane, and glycerol.

[0095] Examples of the aforementioned epoxy (meth)acrylates include, for example, bisphenol A type epoxy acrylates.

[0096] Commercially available products among the aforementioned urethane (meth)acrylates include, for example, urethane (meth)acrylates manufactured by Toa Synthetic Co., Ltd., urethane (meth)acrylates manufactured by DAICL-ALLNEX LTD., urethane (meth)acrylates manufactured by Negami Kogyo Co., Ltd., urethane (meth)acrylates manufactured by Shin-Nakamura Chemical Co., Ltd., and urethane (meth)acrylates manufactured by Kyoeisha Chemical Co., Ltd.

[0097] Examples of urethane (meth) acrylates manufactured by Toa Synthetic Co., Ltd. include M-1100, M-1200, M-1210, and M-1600.

[0098] Examples of urethane (meth)acrylates manufactured by DAICEL-ALLNEX LTD. include EBECRYL210, EBECRYL220, EBECRYL230, EBECRYL270, EBECRYL1290, EBECRYL2220, EBECRYL4827, EBECRYL4842, EBECRYL4858, EBECRYL5129, EBECRYL6700, EBECRYL8402, EBECRYL8803, EBECRYL8804, EBECRYL8807, and EBECRYL9260.

[0099] Examples of urethane (meth)acrylates manufactured by the aforementioned Negami Kogyo Co., Ltd. include ArtResin UN-330, Art Resin SH-500B, Art Resin UN-1200TPK, Art Resin UN-1255, Art Resin UN-3320HB, Art Resin UN-7100, Art Resin UN-9000A, and Art Resin UN-9000H.

[0100] Examples of urethane (meth)acrylates manufactured by Shin-Nakamura Chemical Industry Co., Ltd. include: U-2HA, U-2PHA, U-3HA, U-4HA, U-6H, U-6HA, U-6LPA, U-10H, U-15HA, U-108, U-108A, U-122A, U-122P, U-324A, U-340A, U-340P, U-1084A, U-2061BA, UA-340P, UA-4000, UA-4100, UA-4200, UA-4400, UA-5201P, UA-7100, UA-7200, and UA-W2A.

[0101] Examples of urethane (meth)acrylates manufactured by Kyoeisha Chemical Co., Ltd. include AH-600, AI-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, and UA-306T.

[0102] Other epoxy compounds mentioned above include, for example: resorcinol-type epoxy compounds, biphenyl-type epoxy compounds, thioether-type epoxy compounds, diphenyl ether-type epoxy compounds, dicyclopentadiene-type epoxy compounds, naphthalene-type epoxy compounds, phenolic varnish-type epoxy compounds, o-cresolic varnish-type epoxy compounds, dicyclopentadieneic varnish-type epoxy compounds, biphenyl varnish-type epoxy compounds, naphtholic varnish-type epoxy compounds, glycidylamine-type epoxy compounds, alkyl polyol-type epoxy compounds, rubber-modified epoxy compounds, and glycidyl ester compounds.

[0103] The preferred lower limit for the content of the curable resin in 100 parts by weight of the sealant for display elements of the present invention is 50 parts by weight, and the preferred upper limit is 95 parts by weight. By setting the content of the curable resin in this range, the curability and adhesion of the resulting sealant for display elements are improved. A more preferred lower limit for the content of the curable resin is 60 parts by weight, and a more preferred upper limit is 85 parts by weight.

[0104] The sealant for display elements of the present invention contains a polymerization initiator.

[0105] Examples of polymerization initiators include photoradical polymerization initiators that generate free radicals through light irradiation and thermal radical polymerization initiators that generate free radicals through heating.

[0106] Examples of photoradical polymerization initiators include benzophenone compounds, acetophenone compounds, acylphosphine oxide compounds, dicene compounds, oxime ester compounds, benzoin ether compounds, and thioxanone compounds.

[0107] Specifically, examples of photoradical polymerization initiators include 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-(dimethylamino)-2-((4-methylphenyl)methyl)-1-(4-(4-morpholino)phenyl)-1-butanone, 2,2-dimethoxy-1,2-diphenylethane-1-one, and bis(2,4,6-trimethylbenzyl) Phosphine oxide (acyl) phenyl, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropane-1-one, 1-(4-(2-hydroxyethoxy)-phenyl)-2-hydroxy-2-methyl-1-propane-1-one, 1-(4-(phenylthio)phenyl)-1,2-octanedione 2-(O-benzoyl oxime), 2,4,6-trimethylbenzoyl diphenylphosphine oxide, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, etc.

[0108] The above-mentioned photoradical polymerization initiators can be used alone or in combination of two or more.

[0109] Examples of thermal free radical polymerization initiators include substances composed of azo compounds and organic peroxides. From the viewpoint of suppressing liquid crystal contamination when the obtained display element sealant is used as a sealant for liquid crystal display elements, an initiator composed of azo compounds (hereinafter also referred to as "azo initiator") is preferred.

[0110] The above-mentioned thermal free radical polymerization initiators can be used alone or in combination of two or more.

[0111] Commercially available azo initiators mentioned above include, for example, VPE-0201, VPE-0401, VPE-0601, VPS-0501, VPS-1001, V-65, and V-501 (all manufactured by FUJIFILM Wako Pure Chemical Corporation).

[0112] Examples of the aforementioned organic peroxides include: peroxide ketones, peroxide ketals, hydroperoxides, dialkyl peroxides, peroxide esters, diacyl peroxides, and peroxydicarbonates.

[0113] The preferred lower limit of the content of the polymerization initiator relative to 100 parts by weight of the curable resin is 0.01 parts by weight, and the preferred upper limit is 10 parts by weight. By keeping the content of the polymerization initiator within this range, the resulting sealant for display elements exhibits superior storage stability and curability. A more preferred lower limit of the content of the polymerization initiator is 0.1 parts by weight, and a more preferred upper limit is 5 parts by weight.

[0114] The sealant for display elements of the present invention preferably further contains a thermosetting agent.

[0115] Examples of thermosetting agents include organic acid hydrazides, imidazole derivatives, amine compounds, polyphenolic compounds, and acid anhydrides. Among these, organic acid hydrazides are particularly suitable.

[0116] The above-mentioned thermosetting agents can be used alone or in combination of two or more.

[0117] Examples of the aforementioned organic acid hydrazides include sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid dihydrazide, etc.

[0118] Commercially available examples of the aforementioned organic acid hydrazides include those manufactured by Otsuka Chemical Co., Ltd., and those manufactured by Ajinomoto Fine-Techno Co., Inc.

[0119] Examples of organic acid hydrazides manufactured by Otsuka Chemicals Co., Ltd. include SDH, ADH, and MDH.

[0120] Examples of organic acid hydrazides manufactured by Ajinomoto Fine-Techno Co., Inc. include, for example, AJICURE VDH, AJICURE VDH-J, AJICURE UDH, and AJICURE UDH-J.

[0121] The preferred lower limit of the content of the aforementioned thermosetting agent relative to 100 parts by weight of the aforementioned curable resin is 1 part by weight, and the preferred upper limit is 50 parts by weight. By keeping the content of the aforementioned thermosetting agent within this range, the thermosetting properties can be improved without deteriorating the coatability, storage stability, etc., of the resulting sealant for display elements. A more preferred upper limit of the content of the aforementioned thermosetting agent is 30 parts by weight.

[0122] In order to adjust viscosity, further improve adhesion based on stress dispersion effect, improve linear expansion rate, and further improve moisture resistance, the sealant for display elements of the present invention preferably also contains a filler.

[0123] Inorganic fillers or organic fillers can be used as the fillers mentioned above.

[0124] Examples of inorganic fillers mentioned above include silica, talc, glass beads, asbestos, gypsum, diatomaceous earth, montmorillonite, bentonite, sericite, activated clay, alumina, zinc oxide, iron oxide, magnesium oxide, tin oxide, titanium oxide, calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, aluminum nitride, silicon nitride, barium sulfate, and calcium silicate.

[0125] Examples of organic fillers mentioned above include polyester microparticles, polyurethane microparticles, vinyl polymer microparticles, and acrylic polymer microparticles.

[0126] The preferred lower limit for the content of the filler relative to 100 parts by weight of the curable resin is 10 parts by weight, and the preferred upper limit is 40 parts by weight. By keeping the content of the filler within this range, the effects such as improved adhesion are enhanced without deteriorating the coatability. The more preferred lower limit for the content of the filler is 20 parts by weight, and the more preferred upper limit is 30 parts by weight.

[0127] The sealant for display elements of the present invention preferably further contains a silane coupling agent. The aforementioned silane coupling agent primarily functions as an adhesive aid for better bonding of the sealant for display elements to the substrate, etc.

[0128] As the aforementioned silane coupling agents, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-epoxypropoxypropyltrimethoxysilane, and 3-isocyanate-propyltrimethoxysilane are suitable examples. They exhibit excellent effects in improving adhesion to substrates, etc. Furthermore, when the obtained display element sealant is used as a sealant for liquid crystal display elements, it can suppress the outflow of curable resin into the liquid crystal.

[0129] The above-mentioned silane coupling agents can be used alone or in combination of two or more.

[0130] The preferred lower limit for the content of the silane coupling agent relative to 100 parts by weight of the aforementioned curable resin is 0.1 parts by weight, and the preferred upper limit is 5 parts by weight. By setting the content of the silane coupling agent within this range, the effect of improving adhesion becomes more superior. The more preferred lower limit for the content of the silane coupling agent is 0.3 parts by weight, and the more preferred upper limit is 2 parts by weight.

[0131] The sealant for display elements of the present invention may also contain additives such as light-blocking agents, stress-relaxing agents, reactive diluents, thixotropic agents, spacers, curing accelerators, defoamers, leveling agents, and polymerization inhibitors, as needed.

[0132] As a method for manufacturing the sealant for the display element of the present invention, examples include mixing a curable resin, a polymerization initiator, a thermosetting agent, and additives such as a silane coupling agent added as needed, using a homogenizer, a homogenizer, a universal mixer, a planetary mixer, a kneader, a three-roll mill, or other mixers.

[0133] By mixing conductive microparticles into the sealant for display elements of the present invention, a material with both vertical and horizontal conductivity can be manufactured.

[0134] As the aforementioned conductive particles, metal spheres, particles with a conductive metal layer formed on the surface of resin particles, etc., can be used. Among them, particles with a conductive metal layer formed on the surface of resin particles are suitable because the excellent elasticity of the resin particles allows for conductive connections without damaging the transparent substrate.

[0135] The sealant for display elements of the present invention is suitable for use as a sealant for liquid crystal display elements.

[0136] As for the liquid crystal display element obtained using the sealant for display elements of the present invention, a liquid crystal display element with a narrow bezel design is preferred. Specifically, it is preferable that the width of the frame portion surrounding the liquid crystal display section is 2 mm or less.

[0137] When manufacturing the above-mentioned liquid crystal display element, the coating width of the sealant for the display element of the present invention is preferably 1 mm or less.

[0138] The sealant for display elements of the present invention is suitable for use in manufacturing liquid crystal display elements by liquid crystal dispensing process. Examples of methods for manufacturing liquid crystal display elements by liquid crystal dispensing process using the sealant for display elements of the present invention include the following.

[0139] A liquid crystal display element can be obtained by the following method, in which the following steps are performed first: applying the sealant for the display element of the present invention to a substrate by screen printing, dispensing, or the like to form a frame-shaped sealing pattern. Next, while the sealant for the display element of the present invention is not cured, tiny droplets of liquid crystal are applied to the entire surface within the frame of the sealing pattern, and other substrates are immediately overlapped. Then, the sealant for the display element is cured by irradiating the sealing pattern with ultraviolet light or the like. Alternatively, the step of heating the sealant for the display element can be performed after the step of irradiating the sealing pattern with light.

[0140] The effects of the invention

[0141] According to the present invention, a sealant for display elements can be provided that has both excellent adhesion and moisture-proof properties. Detailed Implementation

[0142] The present invention is illustrated in more detail by the following examples, but the present invention is not limited to these examples.

[0143] (Preparation of curable resin A)

[0144] In a reaction flask, 397 parts by mass of 1,4-cyclohexanediethanol monoacrylate, 336 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic anhydride, and 0.1 parts by mass of hydroquinone as a polymerization inhibitor were added, and the mixture was stirred at 90°C for 5 hours using a covered heater. Next, 340 parts by mass of bisphenol A diglycidyl ether and 0.5 parts by mass of triphenylphosphine were added to the resulting reactants, and the mixture was stirred at 110°C for 5 hours to obtain curable resin A.

[0145] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin A is R in the above formula (1). 1 For hydrogen atoms, R 2 The structure (R) shown in equation (3-1) above 29 (where n is 0 and Ep is a compound derived from the structure of bisphenol A diglycidyl ether).

[0146] (Preparation of curable resin B)

[0147] By changing 397 parts by mass of 1,4-cyclohexanediethanol monoacrylate to 425 parts by mass of 1,4-cyclohexanediethanol monomethacrylate, curable resin B was obtained in the same manner as described above in "(Preparation of curable resin A)".

[0148] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin B is R in the above formula (1). 1 Methyl, R 2 The structure (R) shown in equation (3-1) above 29 (where n is 0 and Ep is a compound derived from the structure of bisphenol A diglycidyl ether).

[0149] (Preparation of curable resin C)

[0150] By changing 340 parts by weight of bisphenol A diglycidyl ether to 374 parts by weight of dicyclopentadiene dimethanol diglycidyl ether, curable resin C was obtained in the same manner as described above in "(Preparation of curable resin A)".

[0151] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin C is R in the above formula (1). 1 For hydrogen atoms, R 2 The structure (R) shown in equation (3-1) above 29 Compounds with methyl group (n = 0) and Ep derived from the structure of dicyclopentadiene-diethanol diglycidyl ether.

[0152] (Preparation of curable resin D)

[0153] In a reaction flask, 397 parts by mass of 1,4-cyclohexanediol monoacrylate, 57 parts by mass of ε-caprolactone, and 0.1 parts by mass of hydroquinone as a polymerization inhibitor were added, and the mixture was stirred at 90°C for 5 hours using a covered heater. Then, 336 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic anhydride were added, and the mixture was stirred for another 5 hours. Next, 340 parts by mass of bisphenol A diglycidyl ether and 0.5 parts by mass of triphenylphosphine were added to the resulting reactants, and the mixture was stirred at 110°C for 5 hours to obtain curable resin D.

[0154] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin D is R in the above formula (1). 1 For hydrogen atoms, R 2 The structure (R) shown in equation (3-1) above 29 X is methyl, n is 0.5 (average value), and Ep is a compound derived from the structure of bisphenol A diglycidyl ether.

[0155] (Preparation of curable resin E)

[0156] By changing 336 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic anhydride to 332 parts by mass of 4-cyclohexene-1,2-dicarboxylic anhydride, curable resin E is obtained in the same manner as described above in "(Preparation of curable resin A)".

[0157] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin E is R in the above formula (1). 1 For hydrogen atoms, R 2 The structure (R) shown in equation (3-2) above 30 (where n is a hydrogen atom, n is 0, and Ep is a compound derived from the structure of bisphenol A diglycidyl ether).

[0158] (Preparation of curable resin F)

[0159] By changing 336 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic anhydride to 533 parts by mass of tetrapropylene succinic anhydride, curable resin F was obtained in the same manner as described above in "(Preparation of curable resin A)".

[0160] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin F is R in the above formula (1). 1 For hydrogen atoms, R 2The structure (R) shown in equation (3-4) above 32 For hydrogen atoms, R 33 Compounds with a structure of 2-dodecenyl, n = 0, and Ep derived from the structure of bisphenol A diglycidyl ether.

[0161] (Preparation of curable resin G)

[0162] By changing 336 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic anhydride to 296 parts by mass of phthalic anhydride, curable resin G was obtained in the same manner as described above in "(Preparation of curable resin A)".

[0163] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin G is R in the above formula (1). 1 For hydrogen atoms, R 2 The structure (R) shown in equation (3-3) above 31 (where n is a hydrogen atom, n is 0, and Ep is a compound derived from the structure of bisphenol A diglycidyl ether).

[0164] (Preparation of curable resin H)

[0165] By changing 397 parts by mass of 1,4-cyclohexanediethanol monoacrylate to 232 parts by mass of 2-hydroxyethyl acrylate, curable resin H was obtained in the same manner as described above in "(Preparation of curable resin A)".

[0166] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin H is the compound shown in formula (4).

[0167]

[0168] (Preparation of Curing Resin I)

[0169] By replacing 397 parts by mass of 1,4-cyclohexanediethanol monoacrylate with 256 parts by mass of 2-hydroxyethyl methacrylate, and replacing 336 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic anhydride with 296 parts by mass of phthalic anhydride, curable resin I was obtained in the same manner as described above in “(Preparation of curable resin A)”.

[0170] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin I was the compound shown in formula (5).

[0171]

[0172] (Preparation of curable resin J)

[0173] By changing 397 parts by mass of 1,4-cyclohexanediethanol monoacrylate to 232 parts by mass of 2-hydroxyethyl acrylate, and changing 336 parts by mass of 4-methylcyclohexane-1,2-dicarboxylic anhydride to 296 parts by mass of phthalic anhydride, curable resin J was obtained in the same manner as described above in "(Preparation of curable resin D)".

[0174] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin J was a mixture of the compound shown in formula (6) and the compound shown in formula (7).

[0175]

[0176]

[0177] (Preparation of curable resin K)

[0178] The amount of bisphenol A diglycidyl ether was changed to 680 parts by weight. Otherwise, curable resin K was obtained in the same manner as described above in "(Preparation of curable resin A)".

[0179] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin K is R in the above formula (II). 1 For hydrogen atoms, R 2 The structure (R) shown in equation (3-1) above 29 The compound is a compound with methyl group (n = 0), n = 1,4-cyclohexylene (Y = 1,4-cyclohexylene), and Ep = a compound derived from the structure of bisphenol A diglycidyl ether.

[0180] (Preparation of curable resin L)

[0181] The amount of bisphenol A diglycidyl ether was changed to 680 parts by weight. Otherwise, curable resin L was obtained in the same manner as described above in "(Preparation of curable resin D)".

[0182] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin L is R in the above formula (II). 1 For hydrogen atoms, R 2 The structure (R) shown in equation (3-1) above 29 X is a methyl group, n is 0.5 (average value), Y is 1,4-cyclohexylene, and Ep is a compound derived from the structure of bisphenol A diglycidyl ether.

[0183] (Preparation of curable resin M)

[0184] The 397 parts by mass of 1,4-cyclohexanediethanol monoacrylate were changed to 232 parts by mass of 2-hydroxyethyl acrylate, and the amount of bisphenol A diglycidyl ether was changed to 680 parts by mass. Otherwise, curable resin M was obtained in the same manner as described above in "(Preparation of curable resin A)".

[0185] pass 1 H-NMR and 13 C-NMR confirmed that the curable resin M is the compound shown in formula (8).

[0186]

[0187] (Examples 1-15, Comparative Examples 1-5)

[0188] According to the mixing ratios recorded in Tables 1-3, each material was stirred in a planetary mixing apparatus (made by THINKY CORPORATION, "Awatori Rentaro") and then uniformly mixed using a ceramic three-roll mill to obtain the sealants for display elements of Examples 1-15 and Comparative Examples 1-5.

[0189] <Evaluation>

[0190] The obtained display elements were evaluated using the sealant as follows. The results are shown in Tables 1-3.

[0191] (Adhesion to the alignment film)

[0192] An imide resin is spin-coated onto a glass substrate with an ITO film, pre-baked at 80°C, and then fired at 230°C to produce a substrate with an alignment film. SE7492 (manufactured by Nissan Chemical Co., Ltd.) is used as the imide resin.

[0193] Using a planetary stirring device, 1 part by mass of spacer particles (manufactured by Sekisui Chemicals Co., Ltd., "Micropearl SP-2050") with an average particle size of 5 μm were uniformly dispersed in 100 parts by mass of the obtained display element sealant. A very small amount of the display element sealant containing the spacer particles was placed in the center of a substrate with an alignment film, and a substrate of the same type with an alignment film was stacked on top. The display element sealant was spread out and irradiated with a metal halide lamp at a wavelength of 365 nm and an illuminance of 100 mW / cm². 2 After 30 seconds of ultraviolet light exposure, the components are heated at 120°C for 1 hour to cure the sealant, resulting in an adhesive test piece. The adhesive strength of the obtained test piece is then measured using a tensiometer.

[0194] The adhesion strength is marked as "◎" for a bond strength of 3.0 kg / cm or higher, "○" for a bond strength of 2.5 kg / cm or higher but less than 3.0 kg / cm, "△" for a bond strength of 2.0 kg / cm or higher but less than 2.5 kg / cm, and "×" for a bond strength less than 2.0 kg / cm. This is used to evaluate the adhesion to the orientation film.

[0195] (Moisture-proof)

[0196] Using a coating machine, the obtained display element is coated with a sealant to a thickness of 200-300 μm onto a smooth release film. Next, a metal halide lamp is used to irradiate the surface at a wavelength of 365 nm and an illuminance of 100 mW / cm². 2 After 30 seconds of ultraviolet light exposure, the display element is heated at 120°C for 1 hour to cure with a sealant, resulting in a film for moisture permeability measurement. A moisture permeability test cup is prepared using the method according to JIS Z 0208, the method for testing moisture permeability of moisture-proof packaging materials (cup method). The obtained moisture permeability measurement film is then placed in a constant temperature and humidity oven at 80°C and 90%RH to measure the moisture permeability.

[0197] The obtained moisture permeability value is less than 60 g / m³. 2 • The 24hr condition is marked with “○”, and 60g / m 2 • More than 24 hours and less than 70g / m 2 The 24hr case is denoted as "△", and 70g / m 2 • For conditions exceeding 24 hours, mark with "×" to evaluate moisture-proof performance.

[0198] (Operability)

[0199] Using a planetary mixer, 1 part by mass of spacer particles (Micropearl SP-2050, manufactured by Sekisui Chemicals Co., Ltd.) with an average particle size of 5 μm were uniformly dispersed in 100 parts by mass of a sealant for display elements. Next, the sealant containing the dispersed spacer particles was filled into a syringe (PSY-10EU-OR, manufactured by Musashi Engineering, Inc.), and after degassing, it was applied to one of two transparent substrates using a dispenser (SHOTMASTER300, manufactured by Musashi Engineering, Inc.) in a frame-like sealing pattern. Then, the other transparent substrate was bonded using a vacuum bonding device under a reduced pressure of 5 Pa to obtain the unit. The obtained unit was irradiated with a metal halide lamp at a wavelength of 365 nm and an illuminance of 100 mW / cm². 2 After 30 seconds of exposure to ultraviolet light, the display element is heated at 120°C for 1 hour to cure it with a sealant, thus obtaining a test piece.

[0200] Observe the sealant used on the display elements in the obtained test pieces. Mark cases where there is no obvious uneven coating of the line width as "○", cases where there is obvious uneven coating of the line width as "△", and cases where there is a broken line as "×". Evaluate the operability.

[0201] [Table 1]

[0202]

[0203] [Table 2]

[0204]

[0205] [Table 3]

[0206]

[0207] Industrial availability

[0208] According to the present invention, a sealant for display elements can provide both excellent adhesion and moisture-proof properties.

Claims

1. A sealant for display elements, characterized in that, Contains curing resin and polymerization initiator. The curable resin comprises at least one selected from the group consisting of compounds represented by formula (I) and formula (II). In equations (I) and (II), R 1 R represents a hydrogen atom or a methyl group. 2 The structure is derived from an optionally substituted dicarboxylic acid or its anhydride, X represents the open ring structure of a lactone, n is 0 or more and 2.0 or less (average), Y represents the optionally substituted aliphatic cyclic structure, and Ep represents the structure derived from a difunctional or higher epoxide compound.

2. The sealant for display elements according to claim 1, wherein, The curable resin comprises a compound of formula (1) as the compound of formula (I). In equation (1), R 1 R represents a hydrogen atom or a methyl group. 2 The structure is derived from a dicarboxylic acid or its anhydride that is optionally substituted, X represents the open ring structure of the lactone, n is 0 or more and 2.0 or less (average), Ep represents the structure derived from a more or less difunctional epoxide, and both 1,4-cyclohexylene groups in formula (1) are optionally partially or completely substituted with hydrogen atoms.

3. The sealant for display elements according to claim 1 or 2, wherein, In equations (I) and (II), R 2 The structure is as shown in equations (2-1), (2-2), (2-3), or (2-4). In equations (2-1) to (2-4), * represents the bonding position. In equation (2-1), R 3 ~R 12 Each of the following independently represents an alkyl group having 1 or more but less than 10 hydrogen atoms, in formula (2-2), R 13 ~R 20 Each of the following independently represents an alkyl group having 1 or more but less than 10 hydrogen atoms, in formula (2-3), R 21 ~R 24 Each of the following independently represents an alkyl group having 1 or more but less than 10 carbon atoms, in formula (2-4), R 25 ~R 28 Each can independently represent an organic group having 1 or more hydrogen atoms and 60 or fewer carbon atoms, or, represent R 25 With R 28 Each is independently an alkyl group having 1 or more but less than 10 carbon atoms, and R 26 With R 27 Bonded structure.

4. The sealant for display elements according to claim 1, 2, or 3, wherein, In equations (I) and (II), R 2 The structure is as shown in equations (3-1), (3-2), (3-3), or (3-4). In equations (3-1) to (3-4), * represents the bonding position. In equation (3-1), R 29 Represents an alkyl group having 1 or more hydrogen atoms and less than 10 carbon atoms, in formula (3-2), R 30 Represents an alkyl group having 1 or more hydrogen atoms and less than 10 carbon atoms, in formula (3-3), R 31 Represents an alkyl group having 1 or more hydrogen atoms and less than 10 carbon atoms, in formula (3-4), R 32 and R 33 Each can independently represent an organic group having 1 or more hydrogen atoms and 60 or fewer carbon atoms, or represent R. 32 With R 33 Bonded structure.

5. The sealant for display elements according to claim 1, 2, 3 or 4, wherein, The total content of the compound represented by formula (I) and the compound represented by formula (II) in 100 parts by mass of the curable resin is more than 5 parts by mass and less than 60 parts by mass.

6. The sealant for display elements according to claim 1, 2, 3, 4 or 5, wherein, The curable resin also contains bisphenol-type epoxy compounds. The total content of the compound represented by formula (I) and the compound represented by formula (II) is 50 parts by mass or more and 600 parts by mass or less, relative to 100 parts by mass of the bisphenol type epoxy compound.

7. The sealant for display elements according to claim 1, 2, 3, 4, 5 or 6, used for manufacturing liquid crystal display elements by liquid crystal dispensing process.

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