JP2021178899A - Anchor coat agent - Google Patents

Abstract

To provide, regarding a moisture trap layer formed in a moisture barrier laminate film, an anchor coat agent capable of forming a ground film effectively suppressing discharge of moisture from the moisture trap layer, even under high-temperature and high-humidity atmosphere.SOLUTION: In an anchor coat agent used for the formation of a ground film of a moisture trap layer in a moisture barrier laminate film, a (meth)acrylic resin, an isocyanate compound and an organic solvent are included, in which 0.5 to 97 mass% of the (meth)acrylic resin is derived from glycidyl group-containing (meth)acrylate, and 1 mass% or more of the (meth)acrylic resin shows a hydroxyl value of 10 mg KOH/g or larger.SELECTED DRAWING: None

Description

The present invention relates to an anchor coating agent for forming an anchor coat as a base of a moisture trap layer provided in a moisture barrier laminated film, and further, has a moisture blocking property formed by the anchor coating agent. Also related to the cured film.

As a means for improving the characteristics of various plastic base materials, particularly gas barrier properties, it is known that an inorganic thin film (inorganic barrier layer) made of silicon oxide or the like is formed on the surface of the plastic base material by vapor deposition. (Patent Document 1), a film provided with such an inorganic thin film is widely used as a barrier film.

Further, various electronic devices developed and put into practical use in recent years, such as organic electroluminescence (organic EL), solar cells, touch panels, and electronic paper, are also required to have a high degree of moisture barrier property. In order to satisfy such a requirement, the present applicant has proposed a moisture barrier laminate having a structure in which moisture trap layers are laminated (Patent Document 2).

The moisture trap layer as described above is formed by applying a coating composition for forming a moisture trap layer on an inorganic barrier layer formed on the surface of a plastic film by vapor deposition or the like and curing the coating composition. be.
The moisture barrier laminate described in Patent Document 2 exhibits excellent moisture barrier properties, and is used as a sealing material for electronic devices such as organic EL.

By the way, recently, the degree of moisture barrier required has been improved with the improvement of the performance of various electronic devices. Therefore, it is necessary to confirm whether the moisture barrier laminated film used as a sealing material has a high moisture barrier property that can satisfy such a requirement. Such a quality test will be carried out by accelerating deterioration in a high temperature and high humidity atmosphere at a level considerably higher than the normal humidity atmosphere in which the electronic device is used.
However, the conventionally known moisture barrier laminated film has a problem that its interlayer adhesion and moisture barrier property are significantly reduced when the moisture barrier property is measured in a high humidity environment, especially in a high temperature and high humidity atmosphere such as a deterioration acceleration test. There is a need for further improvement.

Such a decrease in interlayer adhesion and moisture barrier property is caused by the fact that the moisture trap layer contains an alkaline component and a large amount of moisture is trapped in the moisture trap layer in a high temperature and high humidity environment, and the trapped moisture is combined with the alkaline component. It is considered that this is because the penetration into the other layer causes deterioration of the other layer, for example, the inorganic barrier layer.

Japanese Unexamined Patent Publication No. 2000-255579 JP 2015-96320

Therefore, an object of the present invention is to form a base film that effectively suppresses the release of water from the moisture trap layer even in a high temperature and high humidity atmosphere with respect to the moisture trap layer formed in the moisture barrier laminated film. The purpose is to provide an anchor coating agent.
Another object of the present invention is to provide a cured film formed by applying and curing the above anchor coating agent.

Regarding the moisture barrier property having excellent moisture barrier property in a high temperature and high humidity atmosphere, first, in Japanese Patent Application No. 2019-08677, the inorganic barrier layer (A1) was replaced with a plastic film (A) and a moisture trap layer containing an alkaline component (A). In a moisture barrier laminated film containing B) and used for a deterioration acceleration test in a high temperature and high humidity atmosphere of 85 ° C. or higher and a relative humidity of 85% or higher, the inorganic barrier layer (A1) and the moisture trap layer (A1). A coating layer (C) is provided between the coating layer (C) and the coating layer (C) at 40 ° C. and 90% RH, and the moisture permeability is 6.0 × 10 ⁴ g / m ² / day or less. A moisture barrier laminated film characterized by being formed by a certain polymer has been proposed.

^{That is, the above-mentioned moisture barrier laminated film has a moisture permeability of 6.0 × 10 4} g / at 40 ° C. and 90% RH between the alkali component-containing moisture trap layer (B) and the inorganic barrier layer (A1). By providing the coating layer (C) made of a non-aqueous polymer of m ² / day or less, the barrier properties of the moisture trap layer (B) and the inorganic barrier layer (A1) are fully exhibited, and the temperature is 85 ° C. or higher, relative to the relative. It exhibits excellent moisture barrier properties even in a high-temperature, high-humidity atmosphere with a humidity of 85% or more.

The present inventors further promoted the technique of the above-mentioned prior application (Japanese Patent Application No. 2019-087677), and the underlying film of the moisture trap layer has a constant storage elastic modulus E'with a constant moisture permeability. As a result, it has been found that the permeation of water containing an alkaline component can be effectively suppressed even under high temperature and high humidity, and the deterioration of the water barrier property due to such water permeation can be suppressed for a longer period of time, and the present invention has been completed. rice field.

According to the present invention, in the anchor coating agent used for forming the undercoat of the moisture trap layer in the moisture barrier laminated film,
Contains (meth) acrylic resin, isocyanate compound, and organic solvent.
0.5 to 97% by mass of the (meth) acrylic resin is derived from the glycidyl group-containing (meth) acrylate, and 1% by mass or more of the (meth) acrylic resin exhibits a hydroxyl value of 10 mgKOH / g or more. An anchor coating agent characterized by the above is provided.

The following aspects can be preferably adopted as the anchor coating agent of the present invention.
(1) The (meth) acrylic resin and the isocyanate compound are dissolved or dispersed in an organic solvent, and the solid content concentration is in the range of 1 to 60% by mass.
(2) 1% by mass or more of the isocyanate compound is a polyisocyanate having a weight average molecular weight in the range of 400 to 1200.
(3) The catalyst is contained in the range of 0.02 to 1.0% by mass per the total amount of the (meth) acrylic resin and the isocyanate compound.
(4) The catalyst is a metal catalyst.
(5) Due to polymerization curing, the moisture permeability at 40 ° C. and 90% RH is 6.0 × 10 ⁴ g / m ² / day or less, and the storage elastic modulus E ′ (@ 2πrad) in the viscoelasticity measurement at 85 ° C. A cured product having a / s) of 30 MPa or more is formed.
(6) The cured product is a urethane (meth) acrylate polymer and has a high glass transition point of 85 ° C. or higher.

According to the present invention, it is also a cured film formed in a moisture barrier laminated film, which is obtained by a reaction between a (meth) acrylic resin and an isocyanate compound, and has a moisture permeability at 40 ° C. and 90% RH. A cured film having a storage elastic modulus E'(@ 2πrad / s) of 6.0 × 10 ⁴ g / m ² / day or less and a viscoelasticity measurement at 85 ° C. in the range of 30 MPa or more is provided.

The anchor coating agent of the present invention is particularly used for forming an undercoat of a moisture trap layer provided in a moisture barrier laminated film, and is a solvent-based coating containing a (meth) acrylic resin, an isocyanate compound, and an organic solvent. In the composition, 0.5 to 97% by mass of the (meth) acrylic resin is derived from the glycidyl group-containing (meth) acrylate, and 1% by mass or more of the (meth) acrylic resin is 10 mgKOH / g or more. It has the characteristic of showing a hydroxyl value. That is, this anchor coating agent uses urethane (meth) acrylate formed by the reaction of the (meth) acrylic resin and the isocyanate compound as a film-forming component, which serves as the base film of the moisture trap layer (meth). In relation to the fact that the acrylic resin exhibits a certain amount of glycidyl group and hydroxyl value, the urethane (meth) acrylate of the undercoat has a moisture permeability of 6.0 × 10 ⁴ g / m at 40 ° C. and 90% RH. ^{It is 2} / day or less, and the moisture permeability under high temperature and high humidity is extremely low. Moreover, this urethane (meth) acrylate has a storage elastic modulus E'(@ 2πrad / s) of 30 MPa or more in viscoelasticity measurement at 85 ° C., and loosening of the coating film at high temperature is suppressed. In, it is a viscoelastic body in a state of being hard to be deformed (that is, hard to be peeled off) with respect to a shearing force. As a result, the permeation of the alkali-containing water from the water trap layer is effectively suppressed even under high temperature and high humidity, and the deterioration of other membrane components due to the permeation of the alkali-containing water and the accompanying film peeling are effectively prevented. Excellent moisture barrier properties can be maintained for a long period of time even in a high temperature and high humidity environment.

Therefore, the anchor coating agent of the present invention is particularly preferably applied to a moisture barrier laminated film provided with an inorganic barrier layer which is easily deteriorated by alkali, and a base film is formed on the inorganic barrier layer by the anchor coating agent of the present invention. The moisture barrier laminated film in which the moisture trap layer is formed on this undercoat exhibits high moisture barrier even in a high temperature and high humidity atmosphere, and the performance is evaluated in a short time by the deterioration acceleration test. It also has the advantage of being able to do.

The figure which shows an example of the layer structure of the moisture barrier laminated film which has the undercoat film formed by the anchor coating agent of this invention. The figure which shows the structure of the moisture trap layer (B) in the moisture barrier laminated film of FIG. The figure which shows the other example of the layer structure of the moisture barrier laminated film different from FIG. The figure which shows the other example of the layer structure of the moisture barrier laminated film different from FIG. The figure which shows the other example of the layer structure of the moisture barrier laminated film different from FIG.

<Anchor coating agent>
The anchor coating agent of the present invention contains a (meth) acrylic resin and an isocyanate compound as film-forming components, and such film-forming components are dissolved or dispersed in a solvent. The most important feature of this anchor coating agent is that the cured product (urethane (meth) acrylate polymer) formed by the reaction between the (meth) acrylic resin and the isocyanate compound has a moisture permeability at 40 ° C. and 90% RH. A moisture permeability condition of 6.0 × 10 ⁴ g / m ² / day or less, and a viscoelastic condition that the storage elastic modulus E ′ (@ 2πrad / s) in the viscoelasticity measurement at 85 ° C. is 30 MPa or more. The type and blending ratio of the film-forming component and the solvent type are selected so as to satisfy the above.

For example, when the undercoat of the moisture trap layer formed by the anchor coating agent satisfies the above moisture permeability conditions, the transfer of the alkali-containing moisture contained in the moisture trap layer to another layer is the undercoat. This can be effectively prevented and the alkali deterioration of other layers can be avoided. In order to prevent the permeation of such alkali-containing water, it is preferable that the above-mentioned moisture permeability is smaller. For example, the moisture permeability at 40 ° C. and 90% RH is 5.0 × 10 ⁴ g / m ² /. It is desirable that it is less than or equal to day.

Further, since the undercoat film satisfies the above viscoelastic conditions, the loosening of molecules at high temperature is suppressed, so that the deformation of the undercoat film due to the shearing force is effectively prevented, and the film peels off at high temperature. Can be reliably prevented, and the transfer of alkali-containing water from the water trap layer to another layer is suppressed. That is, the higher the storage elastic modulus E'(@ 2πrad / s) at 85 ° C., the higher the effect of suppressing loosening of the molecules of the underlying film, and the higher the moisture barrier property can be exhibited for a longer period of time. For example, storage at 85 ° C. The elastic modulus E'(@ 2πrad / s) is preferably 30 MPa or more, and more preferably 35 MPa or more. Further, if the storage elastic modulus E'is excessively large, the film forming property may be impaired. Therefore, it is desirable that the storage elastic modulus E'is 1500 MPa or less.

Further, it is desirable that the base film has a large water contact angle to some extent. That is, the larger the water contact angle, the more hydrophobic the coating film becomes, and it is possible to reduce the transfer of moisture absorbed by the moisture trap layer. On the other hand, if the value of the water contact angle is excessively large, the wettability when the moisture trap layer is applied on the base layer (C) may be deteriorated. Therefore, the value is more preferably in the range of 65-100 °, particularly 75-95 °.

In order to achieve the above water contact angle, the value of the solubility parameter (SP value) of the (meth) acrylic resin contained in the anchor coating agent is 8.5 to 10.7, particularly 8.6 to 10.6. It is more preferable to be in the range.

The above-mentioned storage elastic modulus E'dependes on the molecular weight Mc between the cross-linking points of the polymer of the cured polymer. For example, in the polymer having the above-mentioned storage elastic modulus E', the molecular weight between the cross-linking points Mc. Is generally in the range of 5000 g / mol or less. Such a molecular weight Mc between cross-linking points is calculated from the value of the storage elastic modulus E'calculated from the viscoelasticity measurement at 85 ° C. using the rubber elasticity formula, as shown in Examples described later. NS.
Further, in the cured product (urethane (meth) acrylate polymer), the higher the glass transition point Tg, the more the molecular motility at high temperature is suppressed. Therefore, in order to reduce the transfer of moisture absorbed by the moisture trap layer. It will be advantageous. For example, it is optimal that the glass transition point of this cured product is 85 ° C. or higher.

The anchor coating agent of the present invention contains a (meth) acrylic resin, an isocyanate compound and a solvent as essential components, and a cured product (undercoat film of a moisture trap layer) formed by applying this and heat-curing it is appropriate. The components are adjusted so as to satisfy the above-mentioned moisture permeability conditions with a sufficient thickness, and at the same time, further satisfy the viscoelastic conditions.

First, the cured product (urethane (meth) acrylate polymer) that satisfies the moisture permeability conditions as described above is a non-aqueous polymer, and therefore the solvent used must be an organic solvent. When the components are dissolved or dispersed using water or a mixed solvent (aqueous solvent) of water and an organic solvent, the moisture permeability in a high temperature and high humidity atmosphere is increased, and the transfer of water from the water trap layer is suppressed. This is because it cannot be done and alkaline deterioration occurs in other layers (for example, an inorganic barrier layer).

As the organic solvent to be used, an organic solvent that does not become hotter than necessary for heating for solvent volatilization is used, and for example, an alcohol-based organic solvent, a dialkyl glycol ether-based solvent, an ethylene glycol ether-based solvent, a propylene glycol ether-based solvent, Ester-based solvents, ketone-based solvents, ether-based solvents, hydrocarbon-based solvents and the like are used.
These organic solvents are used in an amount such that the anchor coating agent has a viscosity suitable for coating. For example, the solid content concentration of the anchor coating agent is 1 to 60% by mass, particularly about 3 to 50% by mass. Organic solvents are used in.

Further, the (meth) acrylic resin used as a film-forming component must be derived from glycidyl group-containing (meth) acrylate in an amount of 0.5 to 97% by mass, particularly 1.0 to 97% by mass. Adhesion to the moisture trap layer is ensured by the glycidyl group introduced into this (meth) acrylic resin, and when the amount of the glycidyl group is within the above range, the viscoelastic condition is maintained without impairing the adhesion due to the glycidyl group. It is possible to form a cured product that satisfies the above.
Such a glycidyl group-containing (meth) acrylate is represented by, for example, the following formula (1).
CH ₂ = CH (R) -COO- (CH ₂ ) m-G (1)
In the formula, R is a hydrogen atom or a methyl group,
G is a glycidyl group and
m is 0 or an integer greater than or equal to 1.
A typical example of this glycidyl group-containing (meth) acrylate is glycidyl (meth) acrylate (m = 0 in the formula (1)).

Further, this (meth) acrylic resin may contain a component showing a hydroxyl value of 10 mgKOH or more, particularly 10 to 150 mgKOH in an amount of 1% by mass or more in order for the cured product to satisfy a predetermined viscoelastic condition. is necessary. That is, by appropriately containing a (meth) acrylic resin having a hydroxyl group, a viscoelastic body having a network structure satisfying a predetermined viscoelastic condition is formed by a reaction with an isocyanate compound described later. ..

As the monomer used for forming the (meth) acrylic resin exhibiting the hydroxyl value as described above, a hydroxyl group-containing (meth) acrylate is used. Examples of such hydroxyl group-containing (meth) acrylates include 2-hydroxymethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate 2,3-dihydroxypropyl (meth) acrylate, and the like. 2,4-Dihydroxypropyl (meth) acrylate, 2-hydroxymethyl-3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 5-hydroxypentyl (meth) Examples thereof include acrylate, diethylene glycol mono (meth) acrylate, triethylene glycol mono (meth) acrylate, tetraethylene glycol mono (meth) acrylate, pentaethylene glycol mono (meth) acrylate, 2-hydroxypropyl (meth) acrylate and the like. .. Further, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,3-butanediol. Di (meth) acrylates such as di (meth) acrylates, 1,4-butanediol di (meth) acrylates, 1,6-hexanediol di (meth) acrylates, and other trimethylolpropanetri (meth) acrylates. Tri (meth) acrylates can also be used.

The (meth) acrylic resin used in the anchor coating agent of the present invention is a monomer used for forming a normal (meth) acrylic resin as long as the above-mentioned glycidyl group content and hydroxyl value content are satisfied. For example, it may contain a polymer formed from methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate and the like.

Further, the above-mentioned (meth) acrylic resin has a glass transition point Tg of 60 ° C. or higher, more preferably 65 ° C. or higher, still more preferably 70 ° C. from the viewpoint of increasing the glass transition point Tg of the cured product (base film). It is desirable that the temperature is above ° C. Further, the weight average molecular weight (Mw) is preferably 10,000 or more, more preferably 15,000 or more, still more preferably 20,000 or more.

As the isocyanate compound to be reacted with the above (meth) acrylic resin, polyisocyanates having two or more isocyanate groups, for example, diisocyanates such as aromatic diisocyanates, aromatic aliphatic diisocyanates, alicyclic diisocyanates, and aliphatic diisocyanates are used. These can be used alone or in combination of two or more, and further, trifunctional or higher polyisocyanates can be used in combination.

Examples of the aromatic diisocyanate include m- or p-phenylene diisocyanate or a mixture thereof, 4,4'-diphenyldiisocyanate, 1,5-naphthalenediocyanate (NDI), 4,4'-, 2,4'-or 2 , 2'-diphenylmethane diisocyanate or a mixture thereof (MDI), 2,4- or 2,6-toluene diisocyanate or a mixture thereof (TDI), 4,4'-toluene diisocyanate (TODI), 4,4'-diphenyl ether diisocyanate And so on.

Examples of the aromatic aliphatic diisocyanate include 1,3- or 1,4-xylylene diisocyanate or a mixture thereof (XDI), 1,3- or 1,4-tetramethylxylylene diisocyanate or a mixture thereof (TMXDI), ω. , Ω'-diisocyanate-1,4-diethylbenzene and the like.

Examples of the alicyclic diisocyanate include 1,3-cyclopentene diisocyanate, 1,4-cyclohexanediisocyanate, 1,3-cyclohexanediisocyanate, 3-isocyanatemethyl-3,5,5-trimethylcyclohexylisocyanate (isophorone diisocyanate; IPDI). , 4,4'-, 2,4'-or 2,2'-dicyclohexylmethane diisocyanate or a mixture thereof (hydrogenated MDI), methyl-2,4-cyclohexanediisocyanate, methyl-2,6-cyclohexanediisocyanate, 1, Examples thereof include 3- or 1,4-bis (isocyanatemethyl) cyclohexane or a mixture thereof (hydrogenated XDI).

Examples of the aliphatic diisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-, 2,3- or 1,3-butylenediocyanate. , 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanate methylcapate and the like.

In the present invention, among the above-mentioned isocyanate compounds, diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), hexamethylene diisocyanate (HDI), metaxylylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, lysine isocyanate, isophorone diisocyanate (IPDI) and polynuclear condensates of these isocyanates are suitable. Further, a polyisocyanate in which 1% by mass or more of the total amount of the isocyanate compound has a weight average molecular weight in the range of 400 to 1200 is advantageous for forming a cured product having, for example, an average molecular weight between cross-linking points in a predetermined range. ..

In the present invention, a urethane (meth) acrylate polymer (that is, a cured product that forms an undercoat) is formed by polymerizing and curing a (meth) acrylic resin with such an isocyanate compound. The isocyanate group present therein also exhibits reactivity with the ionic group in the ionic polymer in the moisture trap layer, and high adhesion to the moisture barrier layer is ensured. Further, such a urethane (meth) acrylate polymer also exhibits excellent adhesion to an inorganic barrier layer contained in, for example, a moisture barrier laminated film. That is, the isocyanate group exhibits reactivity with the MOH group (M is a metal atom such as Al or Si) existing on the surface of the inorganic barrier layer.

Such an isocyanate compound is 0.1 to 5 equivalents, particularly, when the theoretical amount of isocyanate required for reacting with the OH group (functional group capable of reacting with isocyanate) of the (meth) acrylic resin is 1 equivalent. It is preferable that the anchor coating agent is contained in an amount of 0.3 to 4 equivalents. This makes it possible to form a cured product that satisfies the above-mentioned viscoelastic conditions and moisture permeability conditions, and at the same time, it is possible to have an appropriate number of reaction points with the surface of other layers, resulting in higher adhesion. Sex can be ensured.

From the viewpoint of storage stability, the terminal of the above isocyanate compound may be blocked with a blocking agent, and as such a blocking agent, alcohols such as methanol, ethanol and lactic acid ester; phenol and salicylic acid ester Phenolic hydroxyl group-containing compounds such as ε-caprolactam, amides such as 2-pyrrolidone; oximes such as acetone oxime and methyl ethyl ketone oxime; active methylene compounds such as methyl acetoacetate, ethyl acetoacetate, acetyl acetone, dimethyl malonate and diethyl malonate. ; Etc. are typical, and these blocking agents may be used alone or in combination of two or more.

The anchor coating agent of the present invention may contain a catalyst from the viewpoint of promoting the reaction between the (meth) acrylic resin and the isocyanate compound. Typical examples of such catalysts are amine-based catalysts and metal catalysts.
Amine-based catalysts include 1,4-diazabicyclo (2,2,2) octane, PMDETA, N, N-dimethylcyclohexylamine, N-methyldicyclohexylamine, N, N, N, N-tetramethylpropylene diamine, N. , N, N, N-tetramethylhexamethylenediamine, N-ethylmorpholine, N-methylmorpholine, N, N-dimethylethanolamine, N, N-diethylethanolamine and the like can be raised.
Examples of the metal catalyst include organic tin compounds such as dibutyltin laurylate and organozinc compounds.
These catalysts may be used alone or in combination of two or more. Also, metal catalysts are particularly suitable.

These catalysts are blended in an amount of 0.02 to 1.0 parts by mass per 100 parts by mass of the total amount of the (meth) acrylic resin and the isocyanate compound.

By containing the above catalyst, not only the reaction between the (meth) acrylic resin in the base layer (C) and the isocyanate compound is promoted, but also the OH group and isocyanate existing on the surface of the coating base material (for example, the inorganic barrier layer) are present. The reaction with the compound can also be promoted, and the adhesive force between the coated base material and the base layer (C) can be further strengthened. For example, even when the production speed is high and a high heat load cannot be applied to the formation of the base layer (C) as in actual production, the adhesion between the coated base material and the base layer (C) is stably maintained. be able to.

Further, even if various compounding agents are added to the anchor coating agent of the present invention, as long as the adhesion between the formed cured product (undercoat film) and the moisture trap layer or the inorganic barrier layer is not impaired. good.
Examples of such compounding agents include layered inorganic compounds, stabilizers (antioxidants, heat stabilizers, ultraviolet absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, colorants, fillers, and crystals. Examples include nuclear agents. Of course, as long as the above-mentioned adhesion is not impaired, a resin having no reactivity with isocyanate, for example, an olefin resin may be blended in a small amount.

<Formation of the base film of the moisture trap layer>
The above-mentioned anchor coating agent of the present invention is applied on a predetermined base material layer (for example, an inorganic barrier layer), and is a cured product (urethane) which becomes a base film of a moisture trap layer by heating to a temperature of 100 ° C. or higher and baking. (Meta) acrylate polymer) is formed. That is, a moisture trap layer, which will be described later, is formed on the cured product (undercoat film).
The thickness of the undercoat of such a moisture trap layer is 0.1 μm or more, particularly 0.2 μm or more in order to achieve the above-mentioned moisture permeability, but if it is excessively thick, the moisture barrier property is enhanced by multi-layering. Sometimes, it becomes thicker than necessary, so it is desirable that it is moderately thin, for example, 7 μm or less, particularly 6 μm or less. That is, in the anchor coating agent of the present invention, the moisture permeability at 40 ° C. and 90% RH is 6.0 × 10 ⁴ g / m ² / day or less, particularly 5.0 × 10 ^{4 at such an appropriate thickness.} Excellent moisture permeability of g / m ² / day or less can be realized.

<Moisture barrier laminated film>
A moisture barrier laminated film in which a moisture trap layer is formed on an undercoat film made of an anchor coating agent as described above may cause alkali deterioration, film peeling, etc. even when held in a high temperature and high humidity atmosphere for a long period of time. It is stable and exhibits excellent moisture barrier properties.

For example, in FIG. 1, the moisture barrier laminated film shown by 10 as a whole has a plastic film (A) as a base material, and the surface of the plastic film (A) has an inorganic barrier layer (A1). ) Is formed, and a base film (C) is formed between the inorganic barrier layer (A1) and the moisture trap layer (B) by the anchor coating agent of the present invention. That is, the undercoat film (C) and the moisture trap layer (B) are formed in this order on the inorganic barrier layer (A1) of the plastic film (A).
Further, in the plastic film (A), as shown in FIG. 3, a protective layer (D) may be provided on the inorganic barrier layer (A1). That is, the base film (C) may be directly laminated on the inorganic barrier layer (A1), or as shown in FIG. 3, the protection appropriately provided on the inorganic barrier layer (A1). It may be laminated on the layer (D).

Plastic film (A);
This film (A) serves as a base for the inorganic barrier layer (A1), and is usually made of a thermoplastic or thermosetting resin, depending on its morphology, injection or co-injection molding, extrusion or co-extrusion molding. , Film or sheet molding, compression moldability, cast polymerization, etc.

Generally, a thermoplastic resin is suitable from the viewpoint of moldability, cost, and the like.
Examples of such thermoplastic resins include low density polyethylene, high density polyethylene, polypropylene, poly 1-butene, poly 4-methyl-1-pentene or ethylene, propylene, 1-butene, 4-methyl-1-pentene. Α-olefins such as random or block copolymers such as polyolefins, cyclic olefin copolymers, etc., and ethylene / vinyl acetate copolymers, ethylene / vinyl alcohol copolymers, ethylene / vinyl chloride copolymers, etc. Ethylene / vinyl compound copolymer, polystyrene, acrylonitrile / styrene copolymer, ABS, styrene resin such as α-methylstyrene / styrene copolymer, polyvinyl chloride, polyvinylidene chloride, vinyl chloride / vinylidene chloride copolymer , Polyvinyl compounds such as methyl polyacrylate and polymethyl methacrylate, polyamides such as nylon 6, nylon 6-6, nylon 6-10, nylon 11, and nylon 12, polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate. Thermoplastic polyester such as (PEN), polycarbonate, polyphenylene oxide, and others, polyimide resin, polyamideimide resin, polyetherimide resin, fluororesin, allyl resin, polyurethane resin, cellulose resin, polysulfone resin, polyethersulfone resin. , Ketone resin, amino resin, biodegradable resin such as polylactic acid, and the like. Further, these blends or those obtained by appropriately modifying these resins by copolymerization (for example, an acid-modified olefin resin) may be used.

Further, it is also preferable that the plastic film (A) is formed of a gas barrier resin having excellent oxygen barrier properties such as an ethylene / vinyl alcohol copolymer, and further formed of such a gas barrier resin. It may have a multi-layer structure including the layers.

In the present invention, from the viewpoint of easy availability, cost, moldability, or a barrier property against oxygen to some extent, and further being suitable as a base for the inorganic barrier layer (A1) described later. It is more preferable to use a polyester resin typified by polyethylene terephthalate (PET) or an olefin resin typified by polyethylene or polypropylene as the plastic film (A).

The thickness of such a plastic film (A) is not particularly limited, and may have an appropriate thickness depending on the intended use.

Inorganic barrier layer (A1);
Further, the inorganic barrier layer (A1) provided on the surface of the plastic film (A) may be known by, for example, Japanese Patent Application Laid-Open No. 2015-96320, and may be used for sputtering, vacuum vapor deposition, ion plating and the like. It is said that a high oxygen barrier property can be ensured by an inorganic vapor deposition film formed by typified physical vapor deposition or chemical vapor deposition typified by plasma CVD, for example, a film formed of various metals or metal oxides. It is suitable in that respect. In particular, it is formed using the plastic film (A) as a base by plasma CVD in that it is uniformly formed on a surface having irregularities and exhibits an excellent barrier property not only against oxygen but also against moisture. Is preferable.

As for the vapor deposition film by plasma CVD, a plastic film (A) as a base of the inorganic barrier layer (A1) is arranged in a plasma processing chamber maintained at a predetermined degree of vacuum, and a metal or a compound containing the metal is formed. Gas (reaction gas) and oxidizing gas (usually oxygen or NOx gas) are shielded by a metal wall and depressurized to a predetermined degree of vacuum using a gas supply pipe together with a carrier gas such as argon or helium as appropriate. In this state, a glow discharge is generated by a microwave electric field or a high-frequency electric field, plasma is generated by the electric energy, and the decomposition reaction product of the above compound is deposited on the surface of the plastic film A. It is obtained by forming a film.

As the above reaction gas, it is generally said that a film having a flexible region containing a carbon component at the interface with the underlying film (A) and having a region having a high degree of oxidation and excellent barrier properties can be formed on the flexible region. From the viewpoint, organic metal compounds such as organoaluminum compounds such as trialkylaluminum and gases such as organotitanium compounds, organozirconium compounds and organosilicon compounds are used to form an inorganic barrier layer (A1) in the form of a metal oxide. NS.

Further, the inorganic barrier layer (A1) can be formed on the plastic film (A) by coating or the like without using a method such as thin film deposition. That is, the inorganic barrier layer (A1) formed by the coating has lower properties such as oxygen barrier properties than those formed by the above-mentioned vapor deposition or the like, but depending on the degree of barrier properties against oxygen or the like required. , May be formed by coating.

The inorganic barrier layer (A1) formed by the coating contains polysilazane, a polycondensable silane compound (for example, alkoxysilane), and a polycondensable alumina compound (for example, alkoxyaluminum) as a film-forming component, as appropriate. A typical example is to use an organic solvent solution in which inorganic fine particles such as silica and alumina are mixed, apply the solution to a predetermined surface, heat the mixture, and volatilize the organic solvent to form a film.

Further, the thickness of the above-mentioned inorganic barrier layer (A1) varies depending on the use of the moisture barrier laminated film and the required level of barrier property, but generally, the plastic film (A) as a base for vapor deposition is used. It is preferable that the thickness is such that the water vapor transmission rate of ^{10 -1} g / m ² · day / atom or less, particularly ^10-2 g / m ² · day / atom or less can be secured without impairing the characteristics such as. Although it varies depending on the proportion occupied by the above-mentioned high oxidation degree region, it may generally have a thickness of 4 to 500 nm, particularly about 30 to 400 nm.

As such an inorganic barrier layer (A1), one formed of an aluminum oxide or a silicon oxide is most suitable in the present invention because it exhibits the highest barrier property against oxygen.

The inorganic barrier layer (A1) as described above has the drawback of being reactive with alkali and having low alkali resistance.

Moisture trap layer (B);
The moisture trap layer (B) is formed on the undercoat film (C) formed by the anchor coating agent of the present invention described above, and the moisture flowing in the thickness direction with respect to the moisture barrier laminated film 10 is transferred. Cut off. In addition, an ionic polymer is contained as a film-forming component (that is, a matrix), particularly from the viewpoint of exhibiting high trapping property with respect to water. Further, most preferably, the ionic polymer is used as a matrix, and the matrix has a structure in which a hygroscopic agent having a lower ultimate humidity than the ionic polymer is dispersed. Such a hygroscopic agent has a function of trapping water trapped by an ionic polymer, and by dispersing such a hygroscopic agent, deformation such as swelling due to water absorption is effectively avoided. be able to.

(A) Ionic polymer The ionic polymer used for the moisture trap layer (B) includes the following cationic polymers and anionic polymers.

The cationic polymer is a polymer having a cationic group that can be positively charged in water, for example, a 1st to 3rd amino group, a quaternary ammonium group, a pyridyl group, an imidazole group, a quaternary pyridinium, and the like. be. In such a cationic polymer, the cationic group has a strong nucleophilic action and captures water by hydrogen bonding, so that a matrix having hygroscopicity can be formed.
The amount of cationic groups in the cationic polymer is generally such that the water absorption rate (JIS K-7209-1984) of the hygroscopic matrix formed is 5% or more in a humidity of 80% RH and an atmosphere of 30 ° C., particularly 30% to 45. The amount may be%.

Examples of the cationic polymer include amine-based monomers such as allylamine, ethyleneimine, vinylbenzyltrimethylamine, [4- (4-vinylphenyl) -methyl] -trimethylamine, and vinylbenzyltriethylamine; vinylpyridine, vinylimidazole, and the like. At least one of a cationic monomer represented by a nitrogen-containing heterocyclic monomer; and salts thereof; is appropriately polymerized or copolymerized with another copolymerizable monomer, and further. If necessary, those obtained by partial neutralization by acid treatment are used.
Such a cationic polymer is described in detail in JP-A-2015-96320 and the like, and the details thereof will be omitted, but in general, polyallylamine is suitable from the viewpoint of film forming property and the like.

On the other hand, anionic polymers are molecules of anionic functional groups that can be negatively charged in water, such as carboxylic acid groups, sulfonic acid groups, phosphonic acid groups and acidic bases in which these groups are partially neutralized. It is a polymer that has inside. Anionic polymers having such functional groups can form a hygroscopic matrix because the functional groups capture water by hydrogen bonds.
The amount of anionic functional groups in the anionic polymer varies depending on the type of functional group, but the water absorption rate (JIS K-7209-1984) of the hygroscopic matrix formed is 80% humidity as in the above-mentioned cationic polymer. The amount may be 5% or more, particularly 30% to 45% under an atmosphere of RH and 30 ° C.

Examples of the anionic polymer having a functional group as described above include carboxylic acid-based monomers such as methacrylic acid, acrylic acid and maleic anhydride; α-vinyl halide sulfonic acid, styrene sulfonic acid, vinyl sulfonic acid and the like. At least one of anionic monomers represented by sulfonic acid-based monomers; phosphonic acid-based monomers such as vinyl phosphate; and salts of these monomers; etc. can be appropriately copolymerized. The one obtained by polymerizing or copolymerizing with the monomer of No. 1 and, if necessary, partially neutralizing by an alkali treatment is used.
Such anionic polymers are also described in detail in JP-A-2015-96320 and the like, and the details thereof will be omitted, but in general, poly (meth) acrylic acid and its partially neutralized product (for example, one). Part is Na salt).

Structure of moisture trap layer (B);
With reference to FIGS. 2A or 2B, the moisture trap layer (B) contains a hygroscopic agent having a lower ultimate humidity than the ionic polymer (cationic or anionic polymer) forming the above matrix. It is preferable that it is blended.
By dispersing the hygroscopic agent having a higher hygroscopicity than the matrix in this way, the moisture absorbed in the matrix formed by the above-mentioned ionic polymer is immediately captured by the hygroscopic agent and into the absorbed moisture matrix. Is effectively confined, and not only can the moisture absorbing ability be effectively exerted even in an extremely low humidity atmosphere, but also the swelling of the moisture trap layer (B) due to the absorption of moisture is effectively suppressed.

The highly hygroscopic hygroscopic agent as described above has a humidity of 80% RH and a humidity of 6% or less under environmental conditions of, for example, 30 ° C., provided that the ultimate humidity is lower than that of the ionic polymer. Is preferably used. That is, if the ultimate humidity of this hygroscopic agent is higher than that of the ionic polymer, the moisture absorbed in the matrix is not sufficiently trapped and the moisture is likely to be released, so that the moisture barrier property cannot be expected to be significantly improved. It ends up. Further, even when the ultimate humidity is lower than that of the ionic polymer, if the ultimate humidity measured under the above conditions is higher than the above range, for example, the trapping of moisture in a low humidity atmosphere becomes insufficient, and the moisture barrier property is obtained. May not be fully exhibited.

The above-mentioned hygroscopic agent generally has a water absorption rate (JIS K-7209-1984) of 50% or more in an atmosphere of a humidity of 80% RH and a temperature of 30 ° C., and includes inorganic and organic ones.
Examples of the inorganic hygroscopic agent include zeolite, alumina, activated charcoal, clay minerals such as montmorillonite, silica gel, calcium oxide, magnesium sulfate and the like.
Examples of the organic hygroscopic agent include an anionic polymer or a crosslinked product thereof, which is a partially neutralized product thereof. Examples of this anionic polymer include carboxylic acid-based monomers ((meth) acrylic acid, maleic anhydride, etc.), sulfonic acid-based monomers (vinyl halide sulfonic acid, styrene sulfonic acid, vinyl sulfonic acid, etc.), and phosphones. Examples obtained by polymerizing or copolymerizing at least one of anionic monomers represented by acid-based monomers (vinyl phosphate, etc.) and salts of these monomers with other monomers are mentioned. be able to. Organic hygroscopic agents are particularly effective in applications where transparency is required. For example, fine particles of crosslinked poly (meth) acrylate Na or K are typical organic hygroscopic agents.

In the present invention, a hygroscopic agent having a small particle size is preferable from the viewpoint of having a large specific surface area and exhibiting high hygroscopicity (for example, an average primary particle size of 100 nm or less, particularly 80 nm or less), and an organic system having a particularly small particle size. Polymer hygroscopic agents are optimal.
That is, the hygroscopic agent of the organic polymer has extremely good dispersibility in the matrix of the ionic polymer and can be uniformly dispersed, and as a polymerization method for producing the same, emulsion polymerization, suspension polymerization, etc. By adopting the above, the particle shape can be made into a fine and uniform spherical shape, and by blending this to a certain extent or more, extremely high transparency can be ensured.
In addition, the organic fine hygroscopic agent has a remarkably low ultimate humidity and exhibits high hygroscopicity, and the volume change due to swelling can be extremely reduced by cross-linking. Therefore, while suppressing the volume change, It is most suitable for reducing the humidity of the environmental atmosphere to a state of absolute dryness or a state close to a state of absolute dryness.
As the fine particles of such an organic hygroscopic agent, for example, crosslinked sodium polyacrylate fine particles (average particle diameter of about 70 nm) are in the form of a colloidal dispersion (pH = 10.4) from Toyobo Co., Ltd. It is commercially available under the product name.

The amount of the hygroscopic agent as described above fully exerts its characteristics, significantly improves the moisture barrier property and effectively suppresses the dimensional change due to swelling, and at the same time, is higher than the barrier property exhibited by the inorganic barrier layer (A1). It is set according to the type of ionic polymer from the viewpoint of ensuring the moisture barrier property for a long period of time.
For example, the above-mentioned moisture trap layer (B) exhibits an ultra-barrier property such that ^{the water vapor permeability is 10-5} g / m ^{2 / day or less, especially in applications where an ultra-moisture barrier property is required.} The thickness is set to about 1 μm or more (for example, about 1 μm or more, particularly about 2 to 20 μm), but when the matrix is formed of a cationic polymer, per 100 parts by mass of the ionic polymer in the water trap layer (B). , 50 parts by mass or more, particularly preferably 100 to 900 parts by mass, and more preferably 200 to 600 parts by mass. When the matrix is formed of an anionic polymer, it is preferably present in an amount of 50 parts by mass or more, particularly 100 to 1300 parts by mass, per 100 parts by mass of the anionic polymer in the moisture trap layer B. Further, the amount is more preferably 150 to 1200 parts by mass.

Further, in the water trap layer (B) having the above-mentioned structure, it is preferable that a crosslinked structure is introduced into the ionic polymer. That is, if a crosslinked structure is introduced into the ionic polymer, when water is absorbed, the molecules of the cationic polymer are constrained to each other by the crosslinking, suppressing the volume change due to swelling (moisture absorption) and mechanically. It brings about improvement of target strength and dimensional stability.
Such a cross-linking structure can be introduced by blending a cross-linking agent in the coating composition for forming the water trap layer (B). Especially in the case of anionic polymers, unlike cationic polymers, they only capture water by hydrogen bonds, so by introducing a network structure (crosslinked structure) of spaces suitable for moisture absorption into the matrix, the hygroscopicity is greatly increased. Can be enhanced.

The cross-linking agent for introducing such a cross-linked structure is slightly different between the case where the cross-linked structure is introduced into the cationic polymer and the case where the cross-linked structure is introduced into the anionic polymer.

Crosslinking agents for cationic polymers include a crosslinkable functional group that can react with a cationic group (eg, an epoxy group) and a functional group that can form a siloxane structure in the crosslinked structure through hydrolysis and dehydration condensation (eg, an epoxy group). , Alcocysilyl group) can be used, in particular, the following formula:
X-SiR ¹ _n (OR ² ) _3-n
In the formula, X is an organic group having an epoxy group at the terminal.
R ¹ and R ² are a methyl group, an ethyl group, or an isopropyl group, respectively.
n is 0, 1, or 2.
The silane compound represented by is preferably used.

Such a silane compound has an epoxy group and an alkoxysilyl group as functional groups, and the epoxy group undergoes an addition reaction with _{the functional group of the cationic polymer (for example, NH 2).} On the other hand, the alkoxysilyl group forms a silanol group (SiOH group) by hydrolysis, forms a siloxane structure through a condensation reaction, and grows to finally form a crosslinked structure between the cationic polymer chains. As a result, a crosslinked structure having a siloxane structure is introduced into the matrix of the cationic polymer.
Moreover, the cationic polymer is alkaline, and as a result, when the coating composition containing the cationic polymer is applied to form the moisture trap layer B, the addition reaction between the cationic group and the epoxy group and the dehydration condensation between the silanol groups are carried out. Is also promptly promoted and the crosslinked structure can be easily introduced.

In the present invention, the γ-glycidoxyalkyl group is typical as the organic group X having an epoxy group in the above formula, for example, γ-glycidoxypropyltrimethoxysilane or γ-glycidoxypropylmethyldimethoxy. Silane is preferably used as a cross-linking agent.
Further, those in which the epoxy group in the above formula is an alicyclic epoxy group such as an epoxycyclohexyl group are also suitable as a cross-linking agent. For example, when a compound having an alicyclic epoxy group such as β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane is used as a cross-linking agent, the alicyclic structure is included in the cross-linked structure of the matrix together with the alicyclic structure. The structure is introduced. The introduction of such an alicyclic structure can further effectively exert the function of the matrix of forming a network structure of a space suitable for moisture absorption.

Further, in order to introduce an alicyclic structure into the above crosslinked structure, a compound having a plurality of epoxy groups and an alicyclic group, for example, the following formula (2) :.
GO (C = O) -A- (C = O) O-G (2)
In the formula, G is a glycidyl group and
A is a divalent hydrocarbon group having an aliphatic ring, for example, a cycloalkylene group.
The diglycidyl ester represented by can be used as a cross-linking agent. A typical such diglycidyl ester is represented by the following formula (2-1).

That is, although the diglycidyl ester of the formula (2) does not have an alkoxysilyl group, it introduces an alicyclic structure into the crosslinked structure, so that a network structure of a space suitable for moisture absorption is formed in the matrix. Is effective.

The above-mentioned cross-linking agent is preferably used in an amount of 5 to 60 parts by mass, particularly 15 to 50 parts by mass, per 100 parts by mass of the cationic polymer, and is at least 70% by mass, preferably 80% by mass or more of such a cross-linking agent. It is desirable that the mass% or more is the above-mentioned silane compound.

Further, as a cross-linking agent for introducing a cross-linking structure into the anionic polymer, it has two or more cross-linking functional groups (for example, epoxy groups) capable of reacting with the ionic group of the anionic polymer. The formula (2): in which the compound can be used and also mentioned in the coating composition for a cationic matrix:
GO (C = O) -A- (C = O) O-G (2)
In the formula, G is a glycidyl group and
A is a divalent hydrocarbon group having an aliphatic ring, for example, a cycloalkylene group.
The diglycidyl ester represented by is preferably used.

That is, in the diglycidyl ester of the above formula (2), the epoxy group reacts with the anionic group, and a crosslinked structure including an alicyclic structure by the divalent group A is formed in the matrix. The crosslinked structure including such an alicyclic structure results in suppression of swelling.
In particular, among the above-mentioned diglycidyl esters, those suitable are mentioned above, and in particular, they are represented by the above formula (2-1) from the viewpoint of being able to form a network structure of a space suitable for moisture absorption. Diglycidyl ester is most suitable.

It is desirable to use such a cross-linking agent for an anionic polymer in an amount of 150 parts by mass, particularly 10 to 40 parts by mass, per 100 parts by mass of the anionic polymer.

Formation of moisture trap layer (B);
Further, the above-mentioned moisture trap layer (B) uses a coating composition in which a moisture absorbent and, if necessary, a cross-linking agent are dissolved or dispersed in a predetermined solvent in a resin serving as a matrix, and the above-mentioned inorganic coating composition is used. It is formed by applying it on the base film (C) formed on the barrier layer (A1) and heating and drying to remove the solvent. Such heat drying is usually carried out at a temperature of about 100 to 170 ° C. for a short time of 3 minutes or less, particularly about 0.25 to 1 minute, whereby the inorganic barrier layer ( A moisture trap layer (B) that is firmly adhered to A1) can be formed.

Further, in the coating composition used for forming the moisture trap layer (B) as described above, the solvent is not particularly limited as long as it can be volatilized and removed by heating at a relatively low temperature, and for example, methanol. , Ethanol, propyl alcohol, butanol and other alcoholic solvents, acetone, methyl ethyl ketone and other ketone solvents, or a mixed solvent of these solvents and water, or aromatic hydrocarbon solvents such as benzene, toluene and xylene. However, when the silane compound is blended as a cross-linking agent, it is desirable to use water or a mixed solvent containing water in order to promote its hydrolysis. Further, when forming the water trap layer (B) containing the anionic polymer, it is desirable that the pH is adjusted to about 8 to 12 by adding an alkali (for example, sodium hydroxide or the like).

The above-mentioned solvent is used in an amount such that the coating composition has a viscosity suitable for coating, but the water absorption rate of the hygroscopic matrix formed or for adjusting the viscosity of the coating composition is in an appropriate range. The non-ionic polymer can also be blended in an appropriate amount in order to adjust the viscosity.
Examples of such nonionic polymers include saturated aliphatic hydrocarbon-based polymers such as polyvinyl alcohol, ethylene-propylene copolymer, and polybutylene, styrene-based polymers such as styrene-butadiene copolymer, polyvinyl chloride, or These include styrene-based monomers such as various comonomer (for example, vinyl toluene, vinyl xylene, chlorostyrene, chloromethylstyrene, α-methylstyrene, α-halogenated styrene, α, β, β'-trihalogenated styrene, etc. Examples thereof include those obtained by copolymerizing monoolefins such as ethylene and butylene, and conjugated diolefins such as butadiene and isoprene).

In the above-mentioned moisture barrier laminated film, the moisture trap layer (B) is particularly preferably one containing a cationic polymer as a matrix (deposition component). That is, those having such a cationic polymer need to be heated for a long time at a high temperature of 100 ° C. or higher in order to secure particularly high adhesion. By providing C) as a base, there is also an advantage that the moisture trap layer (B) firmly adhered and held can be formed without heating at such a high temperature for a long time.

The water trap layer (B) used to ensure a high degree of water barrier property contains an alkaline component. That is, when the cationic polymer is used as a film forming component (matrix), an alkali such as an amine is contained in the layer. This is because the cationic polymer contains an amine-based compound for introducing a cationic group such as an amino group into the polymer, and thus contains such an amine-based compound as an unavoidable component. Further, the anionic polymer contains an alkali base of a carboxylic acid, and when water is trapped, an alkali such as NaOH or KOH is generated. Further, even when the most suitable crosslinked sodium polyacrylate or the like is used as the hygroscopic agent, alkalis such as NaOH and KOH are generated by trapping water.
On the other hand, since the inorganic barrier layer (A1) exhibits reactivity with alkali, the alkali resistance is extremely poor, and if the water trap layer (B) is directly provided on the inorganic barrier layer (A1), the water content. The inorganic barrier layer (A1) reacts with the alkali contained in the trap layer (B), and as a result, between the moisture trap layer (B) and the inorganic barrier layer (A1), or with the inorganic barrier layer (A1). Delamination occurs at the interface with the plastic film (A). That is, when such a moisture barrier laminated film is held in a high-temperature and high-humidity atmosphere having a temperature of 85 ° C. or higher and a relative humidity RH of 85% or higher and a deterioration acceleration test is performed, film peeling occurs in a short time. Therefore, the moisture barrier property is significantly reduced.

Therefore, between the inorganic barrier layer (A1) and the moisture trap layer (B), the undercoat film (C) that satisfies the predetermined moisture permeation conditions and viscoelastic conditions by using the above-mentioned anchor coating agent of the present invention. ) (C) is interposed, thereby effectively suppressing the transfer of alkali-containing water from the water trap layer (B).

<Protective layer (D)>
In the present invention, the above-mentioned base film (C) may be a base for the moisture trap layer (B), and therefore, as shown in FIG. 3, on the inorganic barrier layer (A1). A protective layer (D) may be provided, and the above-mentioned base film (C) may be provided on the protective layer (D).

The protective layer (D) is for preventing peeling, scratching, breakage, etc. of the inorganic barrier layer (A1) after film formation, and is, for example, under an accelerated test environment (85 ° C.-85% RH environment). The layer is not particularly limited as long as it does not reduce the barrier property of the barrier film in the above, but is generally formed from two or more kinds of compounds in which the following component (D1) and component (D2) are blended. NS.

The component (D1) is a water-soluble polymer, and examples thereof include polyvinyl alcohol, polyvinylpyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, and sodium alginate. Polyvinyl alcohol is particularly preferable.

The component (D2) is at least one compound selected from the group consisting of organoalkoxysilanes or hydrolysates thereof, metal alkoxides or hydrolysates thereof, and phosphorus compounds.

The above organoalkoxysilane is, for example, the following formula (4) :.
R ^1- Si (OR ² ) ₃ (4)
In the formula, R ¹ is an organic group and
R ² is an alkyl group,
It is represented by.
Examples of the above-mentioned organic group R ¹ include an alkyl group or a group having various functional groups (for example, (meth) acryloyl group, vinyl group, amino group, epoxy group, isocyanate group and the like).
The alkyl group indicated by R ² is not particularly limited, but is generally a lower alkyl group having 4 or less carbon atoms (for example, a methyl group, an ethyl group, a propyl group and a butyl group).

Examples of such organoalkoxysilanes include ethyltrimethoxysilane, (meth) acryloxyapropyltrimethoxysilane, vinyltrimethoxysilane, glycidoxytrimethoxysilane, glycidoxypropyltrimethoxysilane, and epoxycyclohexylethyl. Examples thereof include trimethoxysilane, isocyanatepropyltrimethoxysilane, or a hydrolyzate thereof, and these are used alone or in combination of two or more. Among these, glycidoxytrimethoxysilane containing an epoxy group, epoxycyclohexylethyltrimethoxysilane, and isocyanatepropyltrimethoxysilane containing an isocyanate group are particularly preferable. These organosilanes are not limited to monomers, and compounds such as dimers and trimers can also be used depending on the structure.

Further, the above metal alkoxide is obtained by the following formula (5) :.
M (OR ² ) n (5)
In the formula, M is a metal atom,
R ² is an alkyl group as in the above formula (4), and is an alkyl group.
n is an integer indicating the valence of the metal atom M,
It is a compound represented by.
Examples of such metal alkoxides include tetraethoxysilane and tripropoxyaluminum, and such metal alkoxides may be used alone or in combination of two or more.

Further, the above-mentioned organoalkoxysilane and metal alkoxide can each be used as a component (D2) in the form of a hydrolyzate.
Such a hydrolyzate can be obtained by a known method using an acid or an alkali, and a reaction catalyst such as a tin compound can be used as necessary for the hydrolysis.

Further, examples of the phosphorus compound include phosphoric acid or a salt thereof. Specifically, orthophosphoric acid, pyrophosphoric acid, metaphosphoric acid, or alkali metal salts or ammonium salts thereof; Examples include ammonium salt. Further, a phosphoric acid ester such as triphenyl phosphate can also be used.
These phosphorus compounds can also be used alone or in combination of two or more.

The above-mentioned component (D1) and component (D2) are melt-mixed so as to have a mass ratio (D1) / (D2) = 99/1 to 70/30, and this melt mixture is used as the surface of the inorganic barrier layer (A1). The protective layer (D) is formed by applying to.
The thickness of the protective layer (D) thus formed is generally preferably in the range of 0.01 to 50 μm, particularly preferably 0.1 to 2 μm.

In the examples of FIGS. 1 and 3, the inorganic barrier layer (A1) is provided only on one surface of the plastic film (A), but of course, the inorganic barrier layers (A1) are provided on both sides of the film (A). ) Can be formed, and further, a moisture trap layer (B) can be formed on each of the inorganic barrier layers (A1) formed on both sides with a base film (C) sandwiched between them.

Further, as shown in FIGS. 4 and 5, the base layer (C) can be installed on the side opposite to the inorganic barrier layer (A1) of the moisture trap layer (B). With such a layer structure, it is possible to suppress not only the transfer of the alkaline component to the inorganic barrier layer (A1) but also the transfer of the alkaline component to the opposite side.
For example, when another base material is attached to the moisture trap layer (B) via the adhesive layer by dry laminating, the base layer (C) is provided between the moisture trap layer (B) and the adhesive layer. It is also possible to suppress the transfer of alkaline components to the adhesive layer side. As a result, the adhesion of the entire laminated body can be stably maintained.

The moisture barrier laminated film 10 having the above-mentioned layer structure forms a moisture trap layer (B) by the above-mentioned procedure, releases moisture from the moisture trap layer (B), and then causes the moisture trap layer (B). A dry film is attached to the surface of the container and stored in a protected state, and the dry film is peeled off during use.
On such a moisture trap layer (B), for example, a base film (C) is further formed and a dry laminate is performed to laminate the moisture trap layer (B) on another barrier film or the moisture trap layer (B) provided on the other barrier film. You can also do it.

The moisture barrier laminated film described above does not cause delamination even in a deterioration acceleration test in a high temperature and high humidity atmosphere having a temperature of 85 ° C. or higher and a relative humidity RH of 85% or higher, and has excellent moisture barrier properties. Since it can be exhibited, its quality can be confirmed in a short time, which is extremely advantageous industrially. Of course, it can also be used as a sealing material for electronic devices used in such a high temperature and high humidity usage environment.
Such a moisture barrier laminated film can be suitably used as a film for encapsulating an electronic circuit such as an organic EL element, a solar cell, or electronic paper.

Further, the cured product formed by the anchor coating agent of the present invention is used for forming the base film (C) of the moisture trap layer (B), and the cured product itself is excellent in moisture blocking property. Therefore, it can be used independently as a moisture barrier layer regardless of the moisture trap layer (B).

<Measurement method of molecular weight>
3 mL of the solvent was added to the (meth) acrylic resin and about 10 mg of the sample, and the mixture was gently stirred at room temperature. After visually confirming that it was dissolved, the filtrate was filtered through a 0.45 μm filter, GPC measurement (polystyrene conversion) was performed on the filtrate, and the weight average molecular weight (Mw) was measured. Polystyrene was used as the standard.
Equipment: HLC-8120 manufactured by Tosoh Corporation
Detector: Differential Refractometer Detector RI
Column: TSKgel SuperHM-H × 2 and TSKguard volume SuperH-H as a guard column
Solvent: Chloroform Flow rate: 0.5 mL / min
Column temperature: 40 ° C

<Measurement method of moisture permeability>
The water vapor transmission rate of each base film (C) was measured at 40 ° C. and 90% RH using PERMATRAN (manufactured by MOCON) in which only each resin layer was independently formed.

<Measurement method of glass transition point Tg and storage elastic modulus E'>
The values when the coating film of each base film (C) was prepared and the dynamic viscoelasticity measurement was carried out under the following conditions are described.
Equipment: DMS-6100 manufactured by Hitachi High-Tech Science Corporation
Specimen: size 10 mm x 20 mm, thickness 60 μm
Measurement temperature: 30-130 ° C

<Calculation method of molecular weight Mc between cross-linking points>
The molecular weight Mc between the cross-linking points was calculated using the following formula.
Mc = 3ρRT / Emin
Mc: Molecular weight between crosslinks (g / mol)
ρ: Density of sample coating film (g / cm ³ )
R: Gas constant (8.314J / K / mol)
T: Absolute temperature (K) when the storage elastic modulus is Emin
Emin: Minimum storage modulus (MPa)

<Measurement method of water contact angle>
Under the condition of 23 ° C. and 50% RH, 3 μL of pure water was placed on the base layer (C) using a solid-liquid interface analysis system DropMaster 700 (manufactured by Kyowa Surface Chemistry Co., Ltd.), and the water contact angle was measured.

<Evaluation method for barrier layer deterioration>
A 100 μm-thick PET film was dry-laminated with an adhesive on the prepared moisture barrier laminated film, and aged at 50 ° C. for 3 days to cure the adhesive layer to prepare a T-type peeling test sample.
In an atmosphere of 23 ° C. and 50% RH, a test piece having a width of 15 mm and a length of 200 mm (including a non-adhesive portion of 50 mm) was used in a T-type peeling test, and the laminated body was subjected to measurement conditions at a peeling speed of 300 mm / min. The lamination strength (unit: N / 15 mm) between the moisture barrier laminated film and PET was measured (n = 4).
The value at this time is used as the initial value, and when it is 1N / 15 mm or less, it is ×, when it exceeds 1N / 15 mm and 2N / 15 mm or less, it is Δ, when it exceeds 2N / 15 mm and 3N / 15 mm or less, it is ○, and when it exceeds 3N / 15 mm. Was set to ◎.
Further, the T-type peeling test sample prepared in the same manner was stored at 85 ° C. and 85% RH for 5 days, 10 days, and 20 days, and then the same measurement was carried out for each to measure the laminating strength after moisture absorption.
The value at this time is used as the initial value, and when it is 1N / 15 mm or less, it is ×, when it exceeds 1N / 15 mm and 2N / 15 mm or less, it is Δ, when it exceeds 2N / 15 mm and 3N / 15 mm or less, it is ○, and when it exceeds 3N / 15 mm. Was set to ◎.

<Preparation of Moisture Trap Layer Coating Liquid (B1) Using Cationic Polymer>
Polyallylamine (manufactured by Nittobo Medical, PAA-15C, aqueous solution, solid content 15%) was diluted with water as a cationic polymer so as to have a solid content of 5% by weight to obtain a polymer solution.
On the other hand, γ-glycidoxypropyltrimethoxysilane was used as a cross-linking agent and dissolved in water so as to be 5% by weight to prepare a cross-linking agent solution.
Next, the polymer solution and the cross-linking agent solution were mixed so that the amount of γ-glycidoxypropyltrimethoxysilane was 20 parts by weight with respect to 100 parts by weight of polyallylamine, and the mixed solution was further added as a hygroscopic agent. A crosslinked product of Na polyacrylate (Toyobo, Tuftic HU-820E, aqueous dispersion, solid content 13%) was added so as to be 420 parts by weight with respect to polyallylamine, and the solid content was further increased to 5%. After adjusting with water, the mixture was well stirred to prepare a coating solution (B1) for the moisture trap layer.

<Preparation of Moisture Trap Layer Coating Liquid (B2) Using Anionic Polymer>
Polyacrylic acid (AC-10LP manufactured by Nippon Pure Chemical Industries, Ltd.) was used as an anionic polymer, dissolved in a mixed solvent of water / acetone (80/20 by weight) so that the solid content was 5% by weight, and hydroxideed. Sodium was added so that the neutralization rate of polyacrylic acid was 80%, and a polymer solution was obtained.
Diglycidyl 1,2-cyclohexanedicarboxylic acid as a cross-linking agent was added to this polymer solution so as to be 20 parts by weight with respect to the partially neutralized polyacrylic acid, and then β- (3,4-) as an adhesive. Epoxycyclohexyl) ethyltrimethoxysilane is blended in an amount of 3 parts by weight with respect to the partially neutralized polyacrylic acid, and a granular hygroscopic agent (Toyo Boseki, Tuftic HU-820E, aqueous dispersion, solid content 13%). ) Is compounded so as to be 431 parts by weight with respect to the partially neutralized polyacrylic acid, and further adjusted with a water / acetone mixed solvent (80/20 by weight) so that the total solid content is 5% by weight. Then, the mixture was stirred well to prepare a coating solution (B2) for the moisture trap layer.

<Example 1>
As main agents, acrylic resin A (Mw = 70,000, glass transition point = 100 ° C., OHV = 30, glycidyl group content = 0% by mass) and acrylic resin B (Mw = 3,000, glass transition point = 7). A main polymer solution (solid content 50%) containing 95/5 of the solid content ratio (° C., OHV = 100, glycidyl group content = 30% by mass) was prepared.
Polyisocyanate (Mw = 700) as a curing agent is added to this main polymer solution so as to be 30 parts by mass with respect to 100 parts by mass of the solid content of the main polymer solution, diluted with methyl ethyl ketone, and anchored with a solid content of 20%. A coating agent was prepared.

A commercially available barrier film (toppan printing, GX, base material: PET (12 μm)) having a protective layer (D) on the aluminum oxide layer (inorganic barrier layer) was prepared.
The above coating solution is applied onto the protective layer (D) of this barrier film with a bar coater, and heat-treated with an electric oven under the conditions of a peak temperature of 100 ° C. and a peak temperature holding time of 1 minute, and below 1.0 μm. The stratum (C) was obtained.
A moisture trap layer coating liquid (B1) using the above cationic polymer is coated on the coating layer (C) with a bar coater, and heat-treated under the conditions of a peak temperature of 100 ° C. and a peak temperature holding time of 1 minute to obtain a thickness. A moisture trap layer (B) having a thickness of 3 μm was formed to obtain a moisture barrier laminated film.

<Example 2>
A main polymer solution (solid content 50%) containing an acrylic resin C (Mw = 45,000, glass transition point = 95 ° C., OHV = 45, glycidyl group content = 5% by mass) was prepared as a main agent.
A moisture barrier laminated film was obtained in the same manner as in Example 1 except that this main polymer solution was used.

<Example 3>
A moisture barrier laminated film was obtained in the same manner as in Example 2 except that an amine compound was added in an amount of 0.2 parts by mass per 100 parts by mass of the acrylic resin as a catalyst.

<Example 4>
A moisture barrier laminated film was obtained in the same manner as in Example 2 except that an organotin compound was added in an amount of 0.2 parts by mass per 100 parts by mass of the acrylic resin as a catalyst.

<Example 5>
A moisture barrier laminated film was obtained in the same manner as in Example 2 except that an organozinc compound was added in an amount of 0.2 parts by mass per 100 parts by mass of the acrylic resin as a catalyst.

<Example 6>
A moisture barrier laminated film was obtained in the same manner as in Example 5 except that the amount of catalyst per 100 parts by mass of the acrylic resin was changed to 0.03 mass.

<Example 7>
A moisture barrier laminated film was obtained by the same method as in Example 5 except that the thickness of the base layer (C) was 0.3 μm.

<Example 8>
A moisture barrier laminated film was obtained in the same manner as in Example 5 except that the thickness of the coating layer (C) was 0.15 μm.

<Example 9>
A moisture barrier laminated film was obtained in the same manner as in Example 5 except that the amount of the curing agent per 100 parts by mass of the acrylic resin was changed to 15 parts by mass.

<Example 10>
Same as Example 5 except that it was changed to a commercially available barrier film (Toray film processing, Barrier Rocks 1011HG, base material: PET 12 μm) having aluminum oxide as an inorganic barrier layer and not provided with a protective layer (D). A moisture barrier laminated film was obtained by the method.

<Example 11>
Moisture barrier in the same manner as in Example 5 except that it was changed to a commercially available barrier film (toppan printing, GL-RD, base material: PET 12 μm) having silicon oxide as an inorganic barrier layer and a protective layer (D). A sex laminated film was obtained.

<Example 12>
The same method as in Example 5 except that the film was changed to a commercially available barrier film (Mitsubishi Chemical, Tech Barrier LX, base material: PET 12 μm) having silicon oxide as an inorganic barrier layer and not provided with a protective layer (D). A moisture barrier laminated film was obtained.

<Example 13>
A moisture barrier laminated film was obtained in the same manner as in Example 5 except that the solution was changed to the moisture trap layer coating liquid (B2) using an anionic polymer.

<Example 14>
In Example 6, a moisture barrier laminated film was obtained by the same method as in Example 5 except that the underlayer (C) having a thickness of 1.0 μm was further formed on the moisture trap layer (B).

<Comparative Example 1>
A moisture barrier laminated film was obtained in the same manner as in Example 5 except that no curing agent was added.

<Comparative Example 2>
As a main agent, a main polymer solution (solid content 40%) containing an acrylic resin D (Mw = 69,000, glass transition point = 70 ° C., OHV = 80, glycidyl group content = 0% by mass) was prepared.
A moisture barrier laminated film was obtained in the same manner as in Example 1 except that this main polymer solution was used.

<Evaluation test>
Various characteristics of the moisture barrier laminated film produced above were measured by the above-mentioned method, and the results are shown in Table 1.

(A): Plastic film (A1): Inorganic barrier layer (B): Moisture trap layer (C): Underlayer film (D): Protective layer 10: Moisture barrier laminated film

Claims (8)

Moisture barrier property In the anchor coating agent used to form the undercoat of the moisture trap layer in the laminated film,
Contains (meth) acrylic resin, isocyanate compound, and organic solvent.
0.5 to 97% by mass of the (meth) acrylic resin is derived from the glycidyl group-containing (meth) acrylate, and 1% by mass or more of the (meth) acrylic resin exhibits a hydroxyl value of 10 mgKOH / g or more. Anchor coating agent characterized by. The anchor coating agent according to claim 1, wherein the (meth) acrylic resin and the isocyanate compound are dissolved or dispersed in an organic solvent, and the solid content concentration is in the range of 1 to 60% by mass. The anchor coating agent according to claim 1 or 2, wherein 1% by mass or more of the isocyanate compound is a polyisocyanate having a weight average molecular weight in the range of 400 to 1200. The anchor coating agent according to any one of claims 1 to 3, wherein the catalyst is contained in the range of 0.02 to 1.0% by mass per the total amount of the (meth) acrylic resin and the isocyanate compound. The anchor coating agent according to claim 4, wherein the catalyst is a metal catalyst. Due to polymerization curing, the moisture permeability at 40 ° C. and 90% RH is 6.0 × 10 ⁴ g / m ² / day or less, and the storage elastic modulus E ′ (@ 2πrad / s) in the viscoelasticity measurement at 85 ° C. The anchor coating agent according to any one of claims 1 to 5, wherein a cured product having a pressure of 30 MPa or more is formed. The anchor coating agent according to claim 6, wherein the cured product is a urethane (meth) acrylate polymer and has a high glass transition point of 85 ° C. or higher. A cured film formed in a moisture-barrier laminated film, obtained by the reaction of a (meth) acrylic resin with an isocyanate compound, and having a moisture permeability of 6.0 × 10 ⁴ g / at 40 ° C. and 90% RH. A ^{cured film having m 2} / day or less and having a storage elastic modulus E'(@ 2πrad / s) in the range of 30 MPa or more in viscoelasticity measurement at 85 ° C.

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