TW201940587A - Image display device sealing material and image display device sealing sheet - Google Patents

Abstract

The image display device sealing material includes: a first polyolefin-based resin having a main chain including a styrene skeleton and not modified by a functional group; a second polyolefin-based resin modified by an acid; and a softener.

Description

Image display device sealing material and image display device sealing sheet

The present invention relates to an image display device sealing material and an image display device sealing sheet.

As an image display device including a display element, for example, a liquid crystal display or an organic electroluminescence (EL) display is known. In such an image display device, the display element is sealed with a sealing material in order to suppress deterioration of the display element due to moisture in the atmosphere or the like.

For example, a sealing material is affixed to a to-be-adhered body (for example, a board | substrate) on which a display element is mounted so that a display element may be embedded.

As such a sealing material, for example, a sheet-shaped sealing material containing a styrene-isobutylene-styrene copolymer and an aliphatic petroleum resin has been proposed (for example, refer to Patent Document 1).
[Prior Art Literature]
[Patent Literature]

Patent Document 1: International Publication No. 2015/098648

[Problems to be Solved by the Invention]
However, in order to suppress the intrusion of moisture into the interface between the sealing material and the adherend, it is desirable that the sealant for sealing the display element is stably adhered to the adherend without being affected by external environments such as temperature and humidity.

However, in the sheet-shaped sealing material described in Patent Document 1, under high temperature and high humidity conditions (for example, 60 ° C, 90% RH, etc.), there is a disadvantage that the adhesion force (pressure-sensitive adhesion force) to an adherend decreases.

Therefore, in order to improve the moisture and heat resistance, various studies have been made on the composition of the sheet-shaped sealing material. However, the sealing material for sealing the display element is required to have low moisture permeability or transparency, and it is difficult to balance these characteristics.

The present invention provides an image display device sealing material and an image display device sealing sheet that can reduce the moisture permeability and ensure transparency, and can improve the moisture and heat resistance.
[Means for solving problems]

The present invention [1] includes an image display device sealing material comprising: a first polyolefin-based resin having a main chain including a styrene skeleton and not modified by a functional group; and a second polyolefin-based resin modified by an acid. Resins; and softeners.

The present invention [2] includes the image display device sealing material according to the above [1], wherein the second polyolefin-based resin has a main chain including a styrene skeleton.

The present invention [3] includes the image display device sealing material according to the above [1] or [2], wherein the main chain of the first polyolefin-based resin and / or the second polyolefin-based resin The main chain has an isobutylene skeleton.

The present invention [4] includes the image display device sealing material according to any one of the above [1] to [3], wherein a main chain of the first polyolefin-based resin has an isobutylene skeleton, and the first 2 The main chain of the polyolefin resin does not have an isobutylene skeleton.

The present invention [5] includes an image display device sealing sheet including a sealing layer including the image display device sealing material according to any one of [1] to [4].
[Effect of the invention]

The image display device sealing material and the image display device sealing sheet of the present invention include: a first polyolefin-based resin having a main chain including a styrene skeleton and not modified by a functional group; and a second polyolefin modified by an acid. Based resins; and softeners.

Therefore, the image display device sealing material and the image display device sealing sheet can reduce moisture permeability, ensure transparency, and improve moisture and heat resistance.

＜ Image display device sealing material ＞
The image display device sealing material (hereinafter referred to as a sealing material) of the present invention is a sealing resin composition (a sealing resin composition for an image display device) for sealing a display element described later.

The sealing material contains, as an essential component, a first polyolefin-based resin having a main chain including a styrene skeleton and not modified by a functional group (hereinafter referred to as an unmodified polyolefin-based resin containing a styrene skeleton); Acid-modified second polyolefin resin (hereinafter referred to as acid-modified polyolefin resin); and a softener.

(1) Unmodified polyolefin resin containing a styrene skeleton Unmodified polyolefin resin containing a styrene skeleton is a copolymer of a styrene skeleton-containing monomer and an olefin monomer, and has a Main chain derived from olefin backbone of olefin monomer.

Examples of the styrene skeleton-containing monomer include styrene, α-methylstyrene, vinyl toluene, and isopropenyl toluene. The styrene skeleton-containing monomer may be used alone or in combination of two or more.

Among the monomers containing a styrene skeleton, preferably styrene is used. That is, the styrene skeleton-containing monomer preferably contains styrene.

Examples of the olefin monomer include unsaturated aliphatic olefin monomers having 2 to 10 carbon atoms (for example, ethylene, propylene, butene, isobutylene, butadiene, pentene, pentadiene, isoprene, Hexadiene, methylbutene, etc.), unsaturated alicyclic olefin monomers (e.g., cyclopentadiene, dicyclopentadiene, etc.) having 5 to 20 carbon atoms. The olefin monomer may be used alone or in combination of two or more.

Among the olefin monomers, unsaturated aliphatic olefin monomers having 2 to 10 carbon atoms are preferred, ethylene, butene, and isobutylene are more preferred, and isobutene is particularly preferred.

That is, the olefin monomer preferably contains an unsaturated aliphatic olefin monomer having 2 to 10 carbon atoms, and further preferably contains at least one olefin monomer selected from the group consisting of ethylene, butene, and isobutylene, and more particularly Preferably, isobutene is included.

Therefore, in addition to the styrene skeleton, the main chain of the unmodified polyolefin resin containing a styrene skeleton preferably has an olefin skeleton derived from an unsaturated aliphatic olefin monomer having 2 to 10 carbon atoms, and further Preferably, it has at least one olefin skeleton selected from the group consisting of an ethylene skeleton, a butene skeleton, and an isobutylene skeleton, and particularly preferably has an isobutylene skeleton.

If the main chain of the unmodified polyolefin resin containing a styrene skeleton has an isobutylene skeleton, the transparency of the sealing material can be reliably improved, and the moisture permeability can be reliably reduced.

Examples of such unmodified polyolefin resins containing a styrene skeleton include block copolymers, alternating copolymers, random copolymers, and the like, and preferred examples thereof include block copolymers.

In addition, the polyolefin resin having no modified styrene skeleton was not modified with a functional group. In other words, no functional group is introduced into the unmodified polyolefin resin containing a styrene skeleton.

The functional group is, for example, a polar group having a polarity. Examples of the polar group include an acidic group (for example, a carboxyl group, a phosphate group, a sulfo group, and an acid anhydride group derived from these groups), an epoxy group, a hydroxyl group, an amine group, an imine group, and a (meth) acryl group , Ester groups, etc.

The unmodified polyolefin resin containing a styrene skeleton may be a hydride to which hydrogen is added.

Specific examples of such unmodified polyolefin resin containing a styrene skeleton include a styrene-isobutylene block copolymer (SIB), and a styrene-isobutylene-styrene block. Copolymer (styrene-iso-butene-styrene block copolymer, SIBS), styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-butadiene Olefin-isoprene-styrene block copolymers, styrene-ethylene-butylene-styrene block copolymers (SEBS), and hydrides thereof. The unmodified polyolefin resin containing a styrene skeleton may be used alone or in combination of two or more.

Among the unmodified polyolefin resins containing a styrene skeleton, preferred are styrene-isobutylene block copolymer (SIB), styrene-isobutylene-styrene block copolymer (SIBS), and styrene. -Ethylene-butene-styrene block copolymer (SEBS), more preferably SIB and SIBS, and even more preferably SIB and SIBS.

That is, the unmodified polyolefin resin containing a styrene skeleton preferably contains at least one polyolefin resin selected from the group consisting of SIB, SIBS, and SEBS, and further preferably contains SIB and / or SIBS. Preferably it includes SIB and SIBS. In addition, the unmodified polyolefin resin containing a styrene skeleton preferably contains a polyolefin resin selected from the group consisting of SIB, SIBS, and SEBS (and further preferably SIB and / or SIBS, and more preferably SIB And SIBS).

The weight average molecular weight (Mw) of such an unmodified polyolefin resin containing a styrene skeleton is, for example, 20,000 or more, preferably 30,000 or more, and more preferably 50,000 or more, for example, 300,000 or less, preferably 200,000 or less, and further It is preferably below 100,000. The weight average molecular weight (Mw) can be determined by gel permeation chromatography (GPC) using polystyrene as a standard substance (the same applies hereinafter).

In addition, the melt mass flow rate (MFR) of the unmodified polyolefin resin containing a styrene skeleton is, for example, 0.01 g / 10 min or more, preferably 0.1 g / 10 min or more, and more preferably 0.5 g / 10 min or more, for example, 40 g / 10 min or less, preferably 30 g / 10 min or less, and further preferably 25 g / 10 min or less. The melt mass flow rate (MFR) can be measured in accordance with Japanese Industrial Standards (JIS) K 7210 under the conditions of a temperature of 230 ° C in a cylinder of a plastometer and a load of 2.16 kgf. (The same below).

In addition, the unmodified polyolefin resin containing a styrene skeleton preferably contains: an unmodified polyolefin resin containing a styrene skeleton having an MFR of 10 g / 10 min or more (hereinafter referred to as a high MFR unmodified resin) Polystyrene resin with styrene skeleton), and unmodified polyolefin resin with styrene skeleton with MFR less than 10 g / 10 min (hereinafter referred to as low MFR unmodified polyolefin resin with styrene skeleton ).

If the unmodified polyolefin resin containing a styrene skeleton contains both a high MFR unmodified polyolefin resin containing a styrene skeleton and a low MFR unmodified polyolefin resin containing a styrene skeleton, a sealing material can be realized. Improved initial adhesion strength (close adhesion).

In addition, in a case where the unmodified polyolefin resin containing a styrene skeleton contains both a high MFR unmodified polyolefin resin containing a styrene skeleton and a low MFR unmodified polyolefin resin containing a styrene skeleton, The content ratio of the high MFR unmodified polyolefin resin containing a styrene skeleton is higher than the sum of the high MFR unmodified polyolefin resin containing a styrene skeleton and the low MFR unmodified polyolefin resin containing a styrene skeleton For example, it is 5 mass% or more, preferably 10 mass% or more, for example, 50 mass% or less, preferably 40 mass% or less, still more preferably 30 mass% or less, and even more preferably 20 mass% or less.

When the content ratio of the high MFR unmodified polyolefin resin containing a styrene skeleton falls within the above range, the initial adhesion strength of the sealing material can be reliably improved.

In the unmodified polyolefin resin containing a styrene skeleton, the content ratio of the styrene skeleton is, for example, 10% by mass or more, preferably 15% by mass or more, for example, 40% by mass or less, and preferably 35% by mass or less. .

The content of the unmodified polyolefin resin containing a styrene skeleton in the sealing material is, for example, 1% by mass or more, preferably 5% by mass or more, and further preferably 10% by mass or more, such as 60% by mass or less. It is preferably 50% by mass or less, and further preferably 40% by mass or less.

The content ratio of the unmodified polyolefin resin containing a styrene skeleton, the acid modified polyolefin resin, and the softener is 2% by mass, for example. Above, preferably 5 mass% or more, more preferably 15 mass% or more, particularly preferably 25 mass% or more, for example, 70 mass% or less, preferably 55 mass% or less, further preferably 45 mass% or less, especially It is preferably 35 mass% or less.

The content ratio of the unmodified polyolefin resin containing the styrene skeleton and the acid-modified polyolefin resin is 10% by mass or more, for example. It is preferably at least 20% by mass, further preferably at least 30% by mass, particularly preferably at least 50% by mass, for example, at most 95% by mass, preferably at most 90% by mass, still more preferably at least 80% by mass, particularly preferably at 70 Mass% or less.

If the content ratio of the polyolefin resin that has not been modified with a styrene skeleton is within the above range, the transparency of the sealing material can be surely ensured, and the sealing force (pressure-sensitive adhesive force) of the sealing material can be reliably achieved. Promotion.

(2) Acid-modified polyolefin resin The acid-modified polyolefin resin is a polyolefin resin into which an acidic group is introduced, and is, for example, a reaction product of a polyolefin resin and an acidic group-containing compound having an acidic group.

Examples of the polyolefin resin include a homopolymer of an olefin monomer, a copolymer of a styrene skeleton-containing monomer and an olefin monomer (unmodified polyolefin resin containing a styrene skeleton), and the like.

Among polyolefin resins, homopolymers of olefin monomers and copolymers of styrene skeleton-containing monomers and olefin monomers are preferred, and monomers containing styrene skeletons and olefin monomers are more preferred. Body of copolymers.

Examples of the olefin monomer include the above-mentioned olefin monomer, preferably an unsaturated aliphatic olefin monomer having 2 to 10 carbon atoms, and more preferably ethylene, butene, and isobutylene. The olefin monomer may be used alone or in combination of two or more.

Examples of the styrene skeleton-containing monomer include the styrene skeleton-containing monomer, and preferably styrene. The styrene skeleton-containing monomer may be used alone or in combination of two or more.

That is, the main chain of the acid-modified polyolefin resin contains at least an olefin skeleton derived from an olefin monomer, preferably an olefin skeleton and a styrene skeleton, and more preferably an unsaturated aliphatic group derived from 2 to 10 carbon atoms. The olefin skeleton and styrene skeleton of the olefin monomer are particularly preferably at least one olefin skeleton and styrene skeleton selected from the group consisting of an ethylene skeleton, a butene skeleton, and an isobutylene skeleton.

As described above, the main chain of the acid-modified polyolefin resin may have an isobutylene skeleton. On the other hand, when the main chain of the unmodified polyolefin resin containing a styrene skeleton has an isobutylene skeleton, the main chain of the acid modified polyolefin resin preferably does not have an isobutylene skeleton.

If any of the main chain of the polyolefin resin having no modified styrene skeleton and the main chain of the acid-modified polyolefin resin has an isobutylene skeleton, the transparency of the sealing material and the moisture permeability can be fully exerted. Reduced effect.

Moreover, as a polyolefin resin, a block copolymer, an alternating copolymer, a random copolymer, etc. are mentioned, for example, Preferably a block copolymer is mentioned.

Among such polyolefin resins, preferred are homopolymers of polyisobutylene and styrene-ethylene-butene-styrene block copolymers (SEBS).

As an acidic group of an acidic group containing compound, the said acidic group is mentioned, Preferably, the acidic anhydride group of a carboxyl group and a carboxyl group is mentioned, The acidic anhydride group of a carboxyl group is more preferable.

Specific examples of the acidic group-containing compound include an unsaturated carboxylic acid, an anhydride and a derivative thereof, and preferably an unsaturated carboxylic acid anhydride and a derivative thereof. The acidic group-containing compound may be used alone or in combination of two or more.

Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, and norbornene di Carboxylic acid, bicyclic [2,2,1] hept-2-ene-5,6-dicarboxylic acid, etc.

Examples of the unsaturated carboxylic acid anhydride include the aforementioned unsaturated carboxylic acid anhydrides, and preferably, maleic anhydride is used.

Examples of the unsaturated carboxylic acid derivative include halides, fluoramines, fluorimines, and esters of the unsaturated carboxylic acids. Specific examples of the unsaturated carboxylic acid derivative include maleic chloride, maleimide, dimethyl maleate, monomethyl maleate, diethyl maleate, and fumarate. Diethyl acid, dimethyl itaconic acid, diethyl citraconic acid, dimethyl tetrahydrophthalate, bicyclic [2,2,1] hept-2-ene-5,6-dicarboxylic acid Dimethyl Etc.

Such an acid-modified polyolefin-based resin is prepared by reacting a polyolefin resin with a compound containing an acidic group in the presence of a known radical polymerization initiator (such as di-third butyl peroxide). .

Among such acid-modified polyolefin resins, preferred are reaction products of a homopolymer of polyisobutylene and maleic anhydride, and a styrene-ethylene-butene-styrene block copolymer (SEBS) and The reaction product of maleic anhydride is further preferably a reaction product of SEBS and maleic anhydride. The acid-modified polyolefin resin can be used alone or in combination of two or more.

That is, the acid-modified polyolefin-based resin is preferably composed of a reaction product of a homopolymer of polyisobutylene and maleic anhydride and / or a reaction product of SEBS and maleic anhydride.

The weight average molecular weight (Mw) of such an acid-modified polyolefin resin is, for example, 20,000 or more, preferably 30,000 or more, for example, 300,000 or less, preferably 200,000 or less, and further preferably 100,000 or less.

In addition, when the main chain of the acid-modified polyolefin resin contains a styrene skeleton, the content ratio of the styrene skeleton is, for example, 10% by mass or more, preferably 15% by mass or more, and for example, 40% by mass or less. It is preferably 35 mass% or less.

In addition, the modified mass (content ratio of units (structural units) derived from the acid group-containing compound) in the acid-modified polyolefin resin is, for example, 0.1% by mass or more, preferably 0.5% by mass or more, and for example, 5.0% by mass % Or less, preferably 3.0% by mass or less. Further, the content of the acidic group may be calculated (the same as the amount of the polyolefin resin is added and the acidic group-containing compound, or ¹ H- nuclear magnetic resonance ^{(1 H-nuclear magnetic resonance,} 1 H-NMR) measurement results ).

In addition, the content ratio of the unit (constituting unit) derived from the acid group-containing compound to the total of the unmodified styrene skeleton-containing polyolefin resin and the acid-modified polyolefin resin is, for example, 0.1% by mass or more, It is preferably 0.2% by mass or more, more preferably 0.3% by mass or more, for example, 2.0% by mass or less, more preferably 1.5% by mass or less, still more preferably 1.0% by mass or less, and even more preferably 0.8% by mass or less.

The content of the acid-modified polyolefin resin in the sealing material is, for example, 1% by mass or more, preferably 2% by mass or more, further preferably 5% by mass or more, for example, 60% by mass or less, and preferably 40% by mass. the following.

The content of the acid-modified polyolefin resin is, for example, 1% by mass or more with respect to the total of the unmodified polyolefin resin containing the styrene skeleton, the acid-modified polyolefin resin, and the softener. 3% by mass or more, further preferably 5% by mass or more, particularly preferably 10% by mass or more, particularly preferably 15% by mass or more, for example, 70% by mass or less, preferably 50% by mass or less, and further preferably 40% by mass Below, it is particularly preferably 35 mass% or less, and particularly preferably 25 mass% or less.

In addition, the content ratio of the acid-modified polyolefin resin to the total of the unmodified polyolefin resin containing the styrene skeleton and the acid-modified polyolefin resin is, for example, 5 mass% or more, and preferably 10 mass%. The above is more preferably 20% by mass or more, particularly preferably 30% by mass or more, for example, 90% by mass or less, preferably 80% by mass or less, further preferably 70% by mass or less, and even more preferably 50% by mass or less.

When the content ratio of the acid-modified polyolefin resin is equal to or more than the lower limit described above, the improvement of the moisture and heat resistance of the sealing material can be surely achieved. When the content ratio of the acid-modified polyolefin-based resin is equal to or less than the upper limit described above, it is possible to surely improve the adhesion of the sealing material and decrease the moisture permeability.

In addition, in a case where the unmodified polyolefin resin containing a styrene skeleton contains both a high MFR unmodified polyolefin resin containing a styrene skeleton and a low MFR unmodified polyolefin resin containing a styrene skeleton, The content ratio of the acid-modified polyolefin resin is, for example, 1% by mass or more, and preferably 3% by mass relative to the total of the unmodified polyolefin resin containing the styrene skeleton, the acid-modified polyolefin resin, and the softener. % Or more, for example, 20% by mass or less, preferably 15% by mass or less, further preferably 10% by mass or less, particularly preferably 8% by mass or less, and particularly preferably 5% by mass or less.

In addition, in a case where the unmodified polyolefin resin containing a styrene skeleton contains both a high MFR unmodified polyolefin resin containing a styrene skeleton and a low MFR unmodified polyolefin resin containing a styrene skeleton, The content ratio of the acid-modified polyolefin resin is, for example, 1% by mass or more, and preferably 3% by mass or more, relative to the total of the unmodified polyolefin resin containing the styrene skeleton and the acid-modified polyolefin resin. For example, it is 25% by mass or less, preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less.

In this case, if the content ratio of the acid-modified polyolefin resin is within the above range, the initial adhesion strength of the sealing material can be more surely improved.

(3) Softener A softener is a component that imparts viscosity at room temperature (23 ° C) to a sealing material, and is a resin having a number average molecular weight (Mn) of 10,000 or less.

Examples of the softening agent include polyolefin resins that do not contain a styrene skeleton and have not been acid-modified, and preferably include homopolymers of the olefin monomers.

Among the olefin monomers, unsaturated aliphatic olefin monomers having 2 to 10 carbon atoms are preferable, and at least one selected from the group consisting of ethylene, propylene, isobutylene, and butene is more preferable. The olefin monomer is particularly preferably at least one olefin monomer selected from the group consisting of ethylene, propylene, and butene, and the olefin monomer is particularly preferably butene. The olefin monomer may be used alone or in combination of two or more.

Specific examples of the homopolymer of an olefin monomer include polyisobutylene, polyethylene, polypropylene, polybutene, an ethylene-propylene copolymer, and a propylene-butene copolymer. Polybutylene is preferred. Examples of the olefin and ethylene-propylene copolymer include polybutene. The homopolymer of an olefin monomer can be used individually or in combination of 2 or more types.

That is, the softening agent preferably contains polybutene and / or an ethylene-propylene copolymer, more preferably contains polybutene, and particularly preferably consists of polybutene.

When the softener contains polybutene, it is possible to more surely improve the sealing force of the sealing material and reduce the water vapor transmission rate.

The molecular weight of such a softener is, for example, smaller than the molecular weight of each of the unmodified polyolefin resin containing a styrene skeleton and the acid modified polyolefin resin. The number average molecular weight (Mn) of the softener is, for example, 500 or more, preferably 1,000 or more, and further preferably 2,000 or more, for example, 10,000 or less, and preferably 3500 or less. The number average molecular weight (Mn) can be determined by gel permeation chromatography (GPC) using polystyrene as a standard material (the same applies hereinafter).

The content of the softener in the sealing material is, for example, 10% by mass or more, preferably 20% by mass or more, more preferably 30% by mass or more, for example, 60% by mass or less, and preferably 50% by mass or less.

In addition, the content of the softener is, for example, 20% by mass or more, and preferably 30% by mass or more, relative to the total of the unmodified polyolefin resin containing the styrene skeleton, the acid-modified polyolefin resin, and the softener. For example, it is 70% by mass or less, preferably 60% by mass or less, and further preferably 50% by mass or less.

When the content ratio of the softening agent is equal to or more than the lower limit, the sealing material can be provided with viscosity at normal temperature (23 ° C.), and the sealing material's adhesiveness can be reliably improved.

(4) The optional component sealing material may be composed of the above-mentioned essential components, and may further contain an adhesion-imparting agent as an optional component.

The adhesion-imparting agent is a component that imparts adhesion to a sealing material at a high temperature (60 ° C. or higher).

Examples of the adhesion-imparting agent include an aliphatic adhesion-imparting agent, an alicyclic adhesion-imparting agent, an aromatic adhesion-imparting agent, a rosin-based adhesion-imparting agent, a terpene-based adhesion-imparting agent, and the like. An aromatic adhesion-imparting agent and a terpene-based adhesion-imparting agent are preferred.

Examples of the aromatic adhesion-imparting agent include styrene-based oligomers and C9-based petroleum resins. The aromatic adhesion-imparting agent can be used alone or in combination of two or more.

Among the aromatic adhesion-imparting agents, preferably, a styrene-based oligomer is used.

Examples of the styrene-based oligomer include a polymer of the styrene skeleton-containing monomer, and a copolymer of styrene and α-methylstyrene is preferable.

The number average molecular weight (Mn) of the aromatic adhesion-imparting agent is, for example, 500 or more, preferably 700 or more, for example, 2500 or less, and preferably 2,000 or less.

Examples of the terpene-based adhesion-imparting agent include a terpene phenol resin. The terpene-based adhesion-imparting agent can be used alone or in combination of two or more.

Among the terpene-based adhesion-imparting agents, a terpene phenol resin is preferred.

Terpene phenol is a copolymer (reactant) of a terpene compound and a phenol compound.

The terpene compound is a compound having a hydrocarbon having an isoprene (C ₅ H ₈ ) as a constituent unit as a main skeleton. Examples of terpene compounds include α-pinene, β-pinene, dipentene, limonene, α-phellandrene, β-phellandrene, α-terpinene, and β- Terpinene, γ-terpinene, terpinolene, myrcene, alloocimene, 1,8-cineol, 1,4-eucalyptol, α -Α-terpineol, β-terpineol, γ-terpineol, 4-terpineol, sabinene, camphene, tricyclene, p-menthene -1, paramentene-2, paramentene-3, paramentene-8, para-menthadiene, Δ2-carene, Δ3-pinene, caryophyllene ( caryophyllene), longifolene, etc. Terpene compounds can be used alone or in combination of two or more.

Examples of the phenol compound include phenol, cresol, xylenol, propanol, nonanol, hydroquinone, resorcinol, methoxyphenol, bromophenol, bisphenol A, and bisphenol F. The phenol compound may be used alone or in combination of two or more. Among the phenol compounds, preferred is phenol.

The number average molecular weight (Mn) of the terpene-based adhesion-imparting agent is, for example, 500 or more, preferably 700 or more, for example, 2,500 or less, and preferably 2,000 or less.

Such a terpene-based adhesion-imparting agent may be a commercially available product. Examples of commercially available terpene-based adhesion-imparting agents include YS Polystar T-130 (manufactured by Yasuhara Chemical Co., Ltd.) and YS Polystar T-160 ( (Manufactured by Yasuhara Chemical).

The softening point of such an adhesion-imparting agent is, for example, 80 ° C or higher, preferably 100 ° C or higher, and more preferably 120 ° C or higher, for example, 180 ° C or lower, and preferably 165 ° C or lower. The softening point can be measured in accordance with the method described in JIS K2207 (the same applies hereinafter).

The content of the adhesion-imparting agent in the sealing material is, for example, 0% by mass or more, preferably 5% by mass or more, for example, 60% by mass or less, preferably 50% by mass or less, and further preferably 20% by mass or less.

When the content ratio of the adhesion-imparting agent is greater than or equal to the lower limit, adhesion to the sealing material at a high temperature (60 ° C. or higher) can be provided, and the adhesion of the sealing material in a high-temperature region can be reliably improved.

In addition, the sealing material may contain a silane coupling agent (for example, an epoxy-containing silane coupling agent, etc.), a leveling agent, a filler, an anti-aging agent, a wettability improver, a surfactant, Plasticizers, UV absorbers, preservatives, antibacterials, etc.

＜ Effects ＞
Such a sealing material contains: an unmodified polyolefin resin containing a styrene skeleton having a main chain including a styrene skeleton and not modified by a functional group; an acid modified polyolefin resin modified by an acid; and softening Agent.

Therefore, the sealing material can reduce the moisture permeability (water vapor transmission rate), ensure the transparency, and at the same time, improve the moisture and heat resistance. In particular, in addition to improving the adhesion (pressure-sensitive adhesive force) at normal temperature (23 ° C), the sealing material can also achieve the adhesion (pressure-sensitive adhesive force) under high temperature and high humidity (for example, 60 ° C 90% RH). ) Promotion.

Specifically, the water vapor transmission rate of the sealing material at 40 ° C and 90% RH is, for example, 1 g / m ² · 24 h or more, for example, 20 g / m ² · 24 h or less, and preferably 15 g / m ² · 24 h or less, further preferably 12 g / m ² · 24 h or less, particularly preferably 10 g / m ² · 24 h or less, particularly preferably 7 g / m ² · 24 h or less. The water vapor transmission rate can be measured in accordance with a method described in Examples described later (the same applies hereinafter).

The water vapor transmission rate of the sealing material at 60 ° C and 90% RH is, for example, 10 g / m ² · 24 h or more, for example, 30 g / m ² · 24 h or less, and preferably 25 g / m ² · Less than 24 h.

The haze value of the sealing material is, for example, 0% or more, for example, 5% or less, preferably 2% or less, and further preferably 1% or less. The haze value can be measured by a known haze meter (for example, a haze meter NDH2000 manufactured by Nippon Denshoku Industries, Ltd.).

The dielectric constant at 100 kHz of the sealing material is, for example, 2.0 or more, preferably 2.2 or more, for example, 3.0 or less, and preferably 2.8 or less. In addition, the dielectric constant can be measured by a known dielectric tester (for example, an LCR meter HP4284A manufactured by Agilent Technologies, etc.) and a self-balancing bridge method.

<Image display device sealing sheet>
The sealing material is a product that can be directly circulated separately and can be used industrially. From the viewpoint of handleability, the sealing material is preferably distributed as an image display device sealing sheet.

A sealing sheet 1 as an embodiment of the sealing sheet for an image display device of the present invention will be described with reference to FIG. 1.

The sealing sheet 1 includes a sealing layer 2 including the sealing material, a base film 3 and a release film 4. In addition, the sealing sheet 1 is a part for manufacturing an image display device, and does not include a display element and a substrate on which the display element is mounted. Specifically, the sealing sheet 1 includes a sealing layer 2, a base film 3, and a release film 4, and the parts are separated Ground-distributed devices that can be used in industry.

In order to prevent foreign matter from adhering to the sealing layer 2 and the like, it is preferable to protect the sealing layer 2 by the base film 3 and the release film 4 when the sealing sheet 1 is stored. When the sealing sheet 1 is used, the base film 3 and the release film 4 are peeled off.

The sealing layer 2 includes the sealing material and has a film shape (flat plate shape). Specifically, the sealing layer 2 has a predetermined thickness, extends in a predetermined direction orthogonal to the thickness direction, and has a flat surface and a flat back surface.

The thickness of the sealing layer 2 is, for example, 1 μm or more, preferably 5 μm or more, for example, 100 μm or less, and preferably 30 μm or less.

During the period until the sealing sheet 1 is used, the base film 3 is detachably adhered to the back surface of the sealing layer 2 in order to support and protect the sealing layer 2. That is, the base film 3 is a flexible film that is laminated on the back surface of the sealing layer 2 so as to cover the back surface of the sealing layer 2 when the sealing sheet 1 is shipped, transported, and stored. Before the sheet 1, it can be peeled off from the back surface of the sealing layer 2 in a bending manner.

The base film 3 has a flat plate shape, specifically, has a predetermined thickness, extends in a predetermined direction orthogonal to the thickness direction, and has a flat surface and a flat back surface. The adhesive surface (surface) of the base film 3 is peeled as needed.

Examples of the material of the base film 3 include resin materials such as polyester (such as polyethylene terephthalate (PET)) and polyolefins (such as polyethylene and polypropylene). List polyethylene terephthalate.

Among the base films 3, a film having a moisture-barrier property or a gas-barrier property is preferable, and a film containing polyethylene terephthalate is more preferable. Although the thickness of the base film 3 is appropriately selected depending on the material of the film, the thickness of the base film 3 can be set to, for example, about 25 μm to 150 μm in terms of traceability to a sealing material such as a display element.

During the period until the sealing sheet 1 is used, in order to protect the sealing layer 2, the release film 4 is detachably adhered to the surface of the sealing layer 2. That is, the release film 4 is a flexible film that is laminated on the back surface of the sealant layer 2 so as to cover the surface of the sealant layer 2 during shipment, transportation, and storage of the sealant sheet 1. Before the sealing sheet 1 is used, it can be peeled off from the surface of the sealing layer 2 in a bending manner.

The release film 4 has a flat plate shape, specifically, has a predetermined thickness, extends in a predetermined direction orthogonal to the thickness direction, and has a flat surface and a flat back surface. In addition, the adhesive surface (back surface) of the release film 4 is peeled as needed. Examples of the material of the release film 4 include the same resin material as the base film 3. Although the thickness of the release film 4 is also appropriately selected depending on the material of the film, it can be set to, for example, about 25 μm to 150 μm in terms of tracking properties to a sealing material such as a display element.

Next, the manufacturing method of the sealing sheet 1 is demonstrated.

To manufacture the sealing sheet 1, for example, the sealing material is prepared, and the sealing material is applied to the surface of the base film 3 by a known coating method.

A sealing material is prepared by mixing the said essential component and arbitrary components in the said ratio. In addition, in the production of the sealing sheet 1, the sealing material is preferably diluted in an organic solvent and prepared as a varnish for the sealing material.

The organic solvent is not particularly limited as long as it can disperse or dissolve the essential components and any components uniformly. Examples of the organic solvent include aromatic hydrocarbons (such as benzene, toluene, and xylene), ketones (such as acetone, methyl ethyl ketone, and methyl isobutyl ketone), and ethers (such as dibutyl Ether, tetrahydrofuran, dioxane, ethylene glycol monoalkyl ether, ethylene glycol dialkyl ether, 1-methoxy-2-propanol, etc.), esters (such as ethyl acetate, butyl acetate, etc.) ), Nitrogen-containing compounds (such as N-methylpyrrolidone, dimethylimidazolidone, dimethylformaldehyde, etc.). The organic solvent may be used alone or in combination of two or more.

Among the organic solvents, aromatic hydrocarbons are preferred, and xylene is more preferred.

Then, a sealing material (varnish of the sealing material) applied to the base film 3 is dried, and an organic solvent is volatilized as necessary to form a coating film.

The heating temperature is, for example, 80 ° C or higher, preferably 90 ° C or higher, for example, 110 ° C or lower, and preferably 100 ° C or lower. The heating time is, for example, 3 minutes or more, preferably 5 minutes or more, for example, 30 minutes or less, and preferably 10 minutes or less.

Thereby, the coating film is dried, and a sealing layer 2 made of a sealing material is prepared. Then, the release film 4 is attached to the surface of the sealing layer 2.

The sealing sheet 1 is manufactured based on the above.

<Image display device>
Such a sealing sheet 1 is preferably used for sealing (a display element optical element) of an image display device. An organic EL display with a touch sensor (hereinafter referred to as the organic EL display 10) as an embodiment of the image display device will be described with reference to FIG. 2.

Furthermore, in this embodiment, as the image display device, an organic EL display with a touch sensor is mentioned, but the image display device is not particularly limited. Examples of the image display device include a liquid crystal display (including a liquid crystal display with a touch sensor), an organic EL display (including an organic EL display with a touch sensor), and the like.

The organic EL display 10 includes: an element mounting unit 11; a sealing layer 2; and a cover glass or a barrier film 15.

The element mounting unit 11 includes a substrate 13, an organic EL element 12 as an example of a display element, a barrier layer 16, and an electrode (not shown).

The substrate 13 supports the organic EL element 12. The substrate 13 is preferably flexible.

The organic EL element 12 is a known organic EL element and is mounted on a substrate 13. Although not shown, the organic EL element 12 includes a cathode reflective electrode, an organic EL layer, and an anode transparent electrode.

The barrier layer 16 covers the organic EL element 12 and suppresses moisture in the atmosphere from coming into contact with the organic EL element 12.

The electrodes (not shown) constitute a sensor of an organic EL display with a touch sensor. An electrode (not shown) is located between the substrate 13 and the sealing layer 2 (described later). For example, the electrode (not shown) may be located inside the substrate 13 or may be located on the organic EL element 12.

Regarding the sealing layer 2, the base film 3 and the release film 4 are peeled off in advance, the organic EL element 12 covered with the barrier layer 16 is embedded, and the sealing layer 2 is attached to the substrate 13 (pressure-sensitive adhesion).

A cover glass or a barrier film 15 is disposed on the upper surface of the sealing layer 2. The cover glass or the barrier film 15 includes a glass plate and electrodes of a sensor provided on the lower surface of the glass plate and constituting an organic EL display with a touch sensor, although not shown.

Such an organic EL display 10 has an embedded structure in which the organic EL element 12 is disposed between two electrodes constituting the sensor, or one of the two electrodes constituting the sensor is disposed in the organic EL element 12. On the embedded structure.

＜ Modifications ＞
In the modification, the same reference numerals are given to the same members as those of the embodiment, and detailed descriptions thereof are omitted.

As shown in FIG. 1, the sealing sheet 1 includes a sealing layer 2, a base film 3, and a release film 4, but the image display device sealing sheet of the present invention is not limited to this. The image display device sealing sheet may not include the base film 3 and / or the release film 4 if the sealing layer 2 is provided. That is, the image display device sealing sheet may include only the sealing layer 2 or may include any one of the sealing layer 2 and the base film 3 and the release film 4.

As shown in FIG. 2, the organic EL display 10 includes the barrier layer 16, but is not limited thereto. The organic EL display 10 may not include the barrier layer 16.

In addition, the organic EL display 10 has an embedded structure in which the organic EL element 12 is arranged between two electrodes constituting the sensor, or an embedded structure in which one of the two electrodes is arranged on the organic EL element 12. , But not limited to this.

For example, as shown in FIG. 3, the organic EL display 20 may have a plug-in structure in which two electrodes constituting the sensor are arranged on the upper side than the sealing layer 2. The organic EL display 20 includes the element mounting unit 11, the sealing layer 2, and a sensor unit 25.

The sensor unit 25 is disposed on the sealing layer 2. The sensor unit 25 includes electrodes of a sensor constituting an organic EL display with a touch sensor. In the organic EL display 20, the substrate 13 does not include electrodes.

Each modification described above also exhibits the same functions and effects as those of the first embodiment. The embodiments and modifications described above can be combined as appropriate.
[Example]

Examples are given below to further describe the present invention in detail, but the present invention is not limited to these. Specific numerical values such as blending ratios (including ratios), physical property values, and parameters used in the following descriptions may be replaced with corresponding blending ratios (including ratios), physical property values, and parameters described in the "Embodiment". Recorded upper limit (values defined as "below" and "underfill") or lower limit (values defined as "above" and "exceed"). In addition, unless otherwise mentioned, "parts" and "%" are quality standards.

<Preparation of unmodified polyolefin resin containing a styrene skeleton>
Preparation Example 1 (SIBS / SIB)
Prepared a mixture of SIBSTAR 062M (styrene-isobutylene-styrene block copolymer (SIBS) and styrene-isobutylene copolymer (SIB), SIBS / SIB (mass ratio) = 60/40, styrene skeleton content = 20 Mass%, weight average molecular weight (Mw) = 60,000, MFR = 20 g / 10 min, manufactured by Kaneka Corporation). In addition, Tables 1 to 4 show styrene skeletons, isobutylene skeletons, and modified styrene skeletons among unmodified polyolefin resins containing a styrene skeleton, acid-modified polyolefin resins, softeners, and adhesion-imparting agents. Yes or no.

Preparation Example 2 (SEBS)
G1652 (styrene-ethylene-butene-styrene block copolymer (SEBS), styrene skeleton content = 30% by mass, weight average molecular weight (Mw) = 80,000, manufactured by Kraton) was prepared.

Preparation Example 3 (SIBS)
Prepared SIBSTAR 072T (styrene-isobutylene-styrene block copolymer (SIBS), styrene skeleton content = 30% by mass, weight average molecular weight (Mw) = 65,000, MFR = 6 g / 10 min, Zhongyuan Chemical ( Kaneka).

Preparation Example 4 (SIBS)
Prepared SIBSTAR 102T (styrene-isobutylene-styrene block copolymer (SIBS), styrene skeleton content = 25% by mass, weight average molecular weight (Mw) = 100,000, MFR = 0.6 g / 10 min, Zhongyuan Chemical ( Kaneka).

Preparation Example 5 (SIBS)
Prepared SIBSTAR 103T (styrene-isobutylene-styrene block copolymer (SIBS), styrene skeleton content = 31% by mass, weight average molecular weight (Mw) = 100,000, MFR = 0.1 g / 10 min, Zhongyuan Chemical ( Kaneka).

<Preparation of acid-modified polyolefin resin>
Preparation Example 6 (MSEBS)
3 kg of G1652 (SEBS) was added to 10 L of toluene, and the temperature was raised to 145 ° C under a nitrogen atmosphere to dissolve it in toluene. Further, 382 g of maleic anhydride and 175 g of di-third butyl peroxide (radical polymerization initiator) were supplied to a toluene solution of SEBS under stirring for 4 hours, and then stirred at 145 ° C for 2 hours. hour. After cooling, a large amount of acetone was added to precipitate SEBS modified by maleic anhydride, filtered, washed with acetone, and dried under vacuum.

Thereby, a maleic-modified styrene-ethylene-butene-styrene block copolymer (MSEBS) was prepared. The maleic modified styrene-ethylene-butene-styrene block copolymer (MSEBS) has a weight average molecular weight (Mw) of 75,000, and the maleic modified styrene-ethylene-butene-styrene copolymer The modified mass in the segment copolymer was 1.5% by mass.

Preparation Example 7 (M-polyisobutylene)
G1652 (SEBS) 3 kg was changed to HI-MOL 5H (polyisobutylene, manufactured by JXTG Energy Co., Ltd.) 3 kg, and maleic acid modified polyisobutylene was prepared in the same manner as in Preparation Example 6. Polyisobutylene). The weight average molecular weight (Mw) of the maleic acid modified polyisobutylene was 45,000, and the modified weight in the maleic acid modified polyisobutylene was 1.0% by mass.

<Preparation of unmodified polyolefin resin without styrene skeleton>
Preparation Example 8 (polyisobutylene)
HI-MOL 5H (polyisobutylene, weight average molecular weight (Mw) = 50,000, manufactured by JXTG Energy) was prepared.

＜ Preparation of softeners ＞
Preparation Example 9 (Polybutene)
HV-1900 (polybutene, number average molecular weight (Mn) = 2900, manufactured by JXTG Energy Corporation) was prepared.

Preparation example 10 (hydrocarbon softener A)
1 L of hexane dehydrated and purified was charged into a continuous polymerization reactor with agitating wings under nitrogen replacement, and adjusted to 96 mmol / L of ethyl sesquichloride (Al (C ₂ H ₅ ) _1.5 · After the hexane solution of Cl _1.5 ) was continuously supplied at a rate of 500 ml / h for 1 hour, the hexane solution of VO (OC ₂ H ₅ ) Cl ₂ (catalyst) adjusted to 16 mmol / l was added at 500 ml / h. The supply rate of h was continuously supplied, and the hexane was continuously supplied at a supply rate of 500 ml / h.

In addition, the reaction liquid was continuously extracted from the upper part of the polymerization reactor so that the reaction liquid in the polymerization reactor always became 1 L. Then, a bubble tube was used to supply ethylene gas into the polymerization reactor at a supply rate of 30 L / h, propylene gas at a supply rate of 30 L / h, and hydrogen gas at a supply rate of 90 L / h. Thereby, ethylene and propylene were copolymerized. The copolymerization reaction was carried out at 35 ° C by circulating a refrigerant in a jacket installed outside the polymerization reactor.

Thereafter, the obtained reaction solution (polymerization solution) was deashed with hydrochloric acid, and then charged into a large amount of methanol to precipitate a polyethylene polypropylene copolymer, followed by drying under reduced pressure at 130 ° C for 24 hours.

As a result, polyethylene polypropylene copolymer (PEPP) was prepared as the hydrocarbon-based softener A.

The ethylene content in the hydrocarbon-based softener A was 53.8 mol%. The 40 ° C kinematic viscosity of the hydrocarbon-based softener A was 600 cSt. The number average molecular weight (Mn) of the hydrocarbon-based softener A was 2,600.

Preparation example 11 (hydrocarbon softener B)
Except that the supply rate of ethylene gas was changed to 34 L / h, the supply rate of propylene gas was changed to 34 L / h, and the supply rate of hydrogen gas was changed to 82 L / h, the same procedures as in Preparation Example 10 were performed. As the hydrocarbon-based softener B, polyethylene polypropylene copolymer (PEPP) was prepared.

The ethylene content in the hydrocarbon-based softener B was 54.5 mol%. The 40 ° C kinematic viscosity of the hydrocarbon-based softener B was 1100 cSt. The number average molecular weight (Mn) of the hydrocarbon-based softener B was 3200.

＜ Preparation of adhesion imparting agent ＞
Preparation Example 12 (Adhesion imparting agent A)
Continuously supply a mixture of α-methylstyrene, styrene, and dehydrated purified toluene (capacity ratio: total of monomers / toluene = 1/1) to an autoclave with an actual capacity of 1270 ml equipped with stirring wings, and by Boron trifluoride phenolate complex (1.7 times equivalent of phenol) was diluted 10 times with dehydrated and refined toluene, and polymerization was carried out at a reaction temperature of 5 ° C.

The molar ratio of α-methylstyrene to styrene is 60:40, the supply amount of the mixture of monomer and toluene is 1.0 L / h, and the supply amount of the diluted catalyst is 75 mL. / h.

Next, the reaction solution was transferred to the second-stage autoclave, and the polymerization reaction was continued at 5 ° C. When the total residence time in the first-stage and second-stage autoclaves became 2 hours, the reaction solution was continuously discharged. Then, 1 L of the reaction solution was taken to terminate the polymerization reaction.

Thereafter, a predetermined NaOH aqueous solution was added to the collected reaction solution, and the catalyst residue was deashed. Then, the reaction solution was washed five times with a large amount of water, and then the solvent and unreacted monomer were distilled off under reduced pressure by an evaporator to prepare an α-methylstyrene-styrene copolymer as the adhesion-imparting agent A.

The softening point Tm of the α-methylstyrene-styrene copolymer is 140 ° C, the number-average molecular weight Mn of the α-methylstyrene-styrene copolymer is 1870, and the The weight average molecular weight Mw was 3,230.

Preparation Example 13 (terpene phenol resin)
YS Polystar T130 (terpene phenol resin, manufactured by Yasuhara Chemical) was prepared.

Preparation Example 14 (terpene phenol resin)
YS Polystar T160 (terpene phenol resin, manufactured by Yasuhara Chemical) was prepared.

<Preparation of image display device sealing material>
Examples 1 to 28 and Comparative Examples 1 to 6
Each component shown in Tables 1 to 4 (unmodified polyolefin resin containing styrene skeleton, acid-modified polyolefin resin, polyisobutylene, softener, and adhesive was prepared according to the formula shown in Table 1 to Table 4. Adding agent) is mixed to prepare a sealing material. The sealing material was diluted with xylene (organic solvent) and prepared as a varnish for the sealing material.

＜ Evaluation ＞
· Appearance (with or without turbidity)
The varnish of the sealing material of each example and each comparative example was applied to a PET film (a release-treated PET film) by a coater (trade names: Purex A53, Teijin DuPont film (Teijin Dupont Film (manufactured, thickness: 38 μm, base film), and then dried in a nitrogen purging oven at 90 ° C. for 5 minutes to form a sealing layer having a thickness of 25 μm.

Then, a PET film (release-treated PET film) (trade name: Purex A31, Teijin Dupont Film) was manufactured by a hot laminator with a thickness of 38 μm. Mold film) attached to the sealing layer at room temperature.

Based on the above, a sealing sheet including a base film, a sealing layer, and a release film was prepared.

Then, the presence or absence of white turbidity in the sealing layer was visually confirmed, and evaluated according to the following criteria. The results are shown in Tables 1 to 4.
○: No cloudiness.
Δ: Slightly cloudy.
×: Cloudy.

Water vapor transmission rate (moisture permeability)
In the same manner as in the evaluation of the appearance described above, the sealing sheets of each of Examples and Comparative Examples were prepared.

Then, the release film and the base film were peeled from the sealing layer, and the sealing layer was adhered to the medicine-coated paper to obtain a sample for measurement. The water vapor transmission rate (moisture permeability) of the obtained sample was measured in accordance with JIS Z0208 under the conditions of 40 ° C 90% RH and 60 ° C 90% RH. Then, it converted into the value when the sample thickness was 100 micrometers based on the film thickness of the sample used for measurement. The results are shown in Tables 1 to 4.

Adhesion (adhesive strength)
In the same manner as in the evaluation of the appearance described above, the sealing sheets of each of Examples and Comparative Examples were prepared.

Then, the sealing sheet was cut to 15 mm in width × 10 cm in length, and then the release film was peeled from the sealing layer. Then, the exposed sealing layer was bonded to alkali glass (25 mm in width × 10 cm in length × 2 mm in thickness). After that, the base film was peeled from the sealing layer, and an aluminum foil / PET composite film (Alpet 30-12 manufactured by Panac) was applied on the exposed surface, and the width was 15 mm × 15 cm × thickness. (40 μm) The aluminum surface is placed in contact with the exposed surface, and a load of 2 kg is applied at room temperature (23 ° C) and bonded for 1 minute.

Thereafter, only the spring was used to stretch the aluminum foil / PET composite film so that the peeling angle was 90 °, and the stress at this time was used as the initial adhesion strength.

In addition, a sealing layer to which an alkali glass and an aluminum foil / PET composite film were bonded was separately prepared, and the sealing layer was left to stand at 60 ° C and 90% RH for 3 days.

Thereafter, in the same manner as described above, the aluminum foil / PET composite film was stretched so that the peeling angle was 90 ° using only a spring, and the stress at this time was used as the adhesive strength after moist heat. The results are shown in Tables 1 to 4.

[Table 1]

[Table 2]

[table 3]

[Table 4]

The invention described above is provided as an exemplary embodiment of the invention, which is merely an example and should not be interpreted in a limited manner. Modifications of the present invention, as will be apparent to those skilled in the art, are included in the scope of patents for inventions to be described later.
[Industrial availability]

The image display device sealing material and the image display device sealing sheet of the present invention can be preferably used as a sealing material for various image display devices, specifically, as a sealing material for a liquid crystal display, an organic EL display, or the like.

1‧‧‧seal

2‧‧‧Sealing layer

3‧‧‧ basement membrane

4‧‧‧ release film

10‧‧‧Organic EL Display

11‧‧‧component mounting unit

12‧‧‧Organic EL element

13‧‧‧ substrate

15‧‧‧ Cover glass or barrier film

16‧‧‧ barrier

20‧‧‧Organic EL Display

25‧‧‧ Sensor Unit

FIG. 1 is a side sectional view of a sealing sheet as an embodiment of the sealing sheet of an image display device of the present invention.

FIG. 2 is an embodiment of an image display device including a sealing layer shown in FIG. 1 (a state having an in-cell structure or an on-cell structure) with touch; A side sectional view of an organic EL display of a sensor.

FIG. 3 is a side cross-sectional view of an organic EL display with a touch sensor as another embodiment of the image display device (an aspect having an out cell structure).

Claims (5)

A sealing material for an image display device, comprising: The first polyolefin resin having a main chain including a styrene skeleton and not modified by a functional group; Acid-modified second polyolefin resin; and Softener. The sealing material for an image display device according to claim 1, wherein the second polyolefin-based resin has a main chain including a styrene skeleton. The sealing material for an image display device according to claim 1, wherein the main chain of the first polyolefin-based resin and / or the main chain of the second polyolefin-based resin has an isobutylene skeleton. The sealing material for an image display device according to item 1 of the scope of patent application, wherein the main chain of the first polyolefin-based resin has an isobutylene skeleton, and The main chain of the second polyolefin-based resin does not have an isobutylene skeleton. An image display device sealing sheet comprising a sealing layer including the image display device sealing material according to item 1 of the scope of patent application.