JP2020151854A - Gas barrier laminate and method for manufacturing the same - Google Patents

Abstract

To provide a gas barrier laminate that includes a gas barrier layer having high adhesion to a substrate, is capable of maintaining excellent adhesion to the substrate even when subjected to retort sterilization treatment, and has excellent crack resistance, and a method for manufacturing the same.SOLUTION: There is provided a gas barrier laminate having an anchor coat layer 2 made of a polyurethane resin and a silane coupling agent on at least one surface of a base material 1, and having a gas barrier layer 3 containing at least a metal oxide on the anchor coat layer 2.SELECTED DRAWING: Figure 1

Description

The present invention relates to a gas barrier laminate, and more specifically, the gas barrier layer has a high adhesive force to a base material, and maintains an excellent adhesive force to a base material even when subjected to a retort sterilization treatment. The present invention relates to a gas barrier laminate having excellent crack resistance and a method for producing the same.

It has been conventionally known that a film containing a metal atom and a phosphorus atom as constituent components is formed on a plastic base material to form a gas barrier laminate.
For example, in Patent Documents 1 and 2 below, 50 to 100% of metal atoms are iron or aluminum, 0 to 50% are selected from tin, titanium and zirconium, and 0 to 20% of metal atoms are zinc and chromium. , A molded product having a gas permeation-preventing coating made of a metal salt of ortholithic acid selected from magnesium is described.
Further, as a multilayer structure having a gas barrier layer containing aluminum, for example, in Patent Document 3 below, a composite structure having a base material (X) and a layer (Y) laminated on the base material (X). The layer (Y) contains a reaction product (R), and the reaction product (R) is a reaction product formed by at least a reaction between a metal oxide (A) and a phosphorus compound (B). the layer in the range of 800～1400Cm ^-1 wave number infrared absorption is maximum in the infrared absorption spectrum of (Y) ^{(n 1)} is in the range of 1080~1130cm ^-1, constituting the metal oxide (a) A composite structure is described in which the metal atom (M) is aluminum.

It has been described that the composite structure has excellent gas barrier properties and water vapor barrier properties, and can maintain excellent super barrier properties at a high level even after retort treatment. However, this composite structure is a base material after retort treatment. There is a problem that the interlayer adhesion between the gas barrier layer and the gas barrier layer is inferior.
In order to solve such a problem, the following Patent Document 4 describes a base material (X), a layer (Z) laminated on the base material (X), and a layer (Z) laminated on the base material (Z). The layer (Z) contains a reaction product of a polyol resin (K) having a silanol group in the resin skeleton and an isocyanate-based curing agent (L), and contains a polyol resin (K). ) And the isocyanate component contained in the isocyanate-based curing agent (L) are in the range of polyol component: isocyanate component = 4000: 1 to 300: 1 in terms of solid content weight ratio, and the thickness of the layer (Z) is 1. A multilayer structure has been proposed in which the layer (Y) is in the range of ~ 200 nm and contains the reaction product (D) of the compound (A) containing aluminum and the phosphorus compound (B).

Special Publication No. 55-50789 Special Publication No. 57-42032 Patent No. 4961054 JP-A-2018-1574

However, in the multilayer structure described in Patent Document 4, when the layer (Y) is formed on the layer (Z), it is necessary to remove the solvent and react the isocyanate component, and a continuous gas barrier layer is formed. Difficult to form. Further, since the formation of the layer (Y) requires heating at a high temperature, it is difficult to apply it to a plastic base material having low heat resistance, and the heating at this high temperature causes the layer (Y) and the layer. There was a risk that a difference in shrinkage rate would occur between (Z) and cracks would occur in the barrier layer (Y).
Therefore, an object of the present invention is that the gas barrier layer has a high adhesive force to the base material, the excellent adhesive force to the base material is maintained even when subjected to the retort sterilization treatment, and the crack resistance is also excellent. It is an object of the present invention to provide a gas barrier laminate and a method for producing the same.

According to the present invention, an anchor coat layer composed of a polyurethane resin and a silane coupling agent is provided on at least one surface of the base material, and a gas barrier layer containing at least a metal oxide is provided on the anchor coat layer. A gas barrier laminate characterized by this is provided.
In the gas barrier laminate of the present invention,
1. 1. The glass transition temperature of the anchor coat layer is 80 ° C. or higher.
2. 2. The silane coupling agent is an epoxy silane compound.
3. 3. The gas barrier layer is composed of a metal oxide of aluminum and / or iron and a phosphoric acid compound.
4. The base material is a film made of polyethylene terephthalate, polybutylene terephthalate, or polypropylene.
Is preferable.

According to the present invention, an anchor coat layer forming composition containing a polyurethane resin and a silane coupling agent is applied to at least one surface of the base material, and the anchor coat layer forming composition is subjected to a drying treatment. After removing the solvent, the composition for forming a gas barrier layer containing a metal oxide and a phosphoric acid compound is applied onto the composition for forming an anchor coat layer, and then the composition is subjected to heat treatment to perform an anchor coat. Provided is a method for producing the above-mentioned gas barrier laminate, which comprises forming a layer and a gas barrier layer.

In the gas barrier laminate of the present invention, the gas barrier layer having excellent gas barrier properties is laminated on the base material with high adhesive force, and has excellent interlayer adhesion even after the retort sterilization treatment.
Further, by using a polyurethane resin having a high glass transition temperature as the main agent constituting the anchor coat layer, crack resistance during heat treatment at the time of forming the gas barrier layer can be improved, and the composition for forming the gas barrier layer can be anchored. It can be continuously coated on the coating layer forming composition, and the suitability for continuous coating can be imparted.
Further, in the method for producing a gas barrier laminate of the present invention, since an anchor coat layer and a gas barrier layer can be formed at a relatively low temperature, polypropylene such as polyethylene terephthalate and polybutylene terephthalate is used as a base material. can do.

It is a figure which shows the cross-sectional structure of an example of the gas barrier laminated body of this invention.

(Anchor coat layer)
In the gas barrier laminate of the present invention, as shown in FIG. 1, an anchor coat layer 2 composed of a polyurethane resin and a silane coupling agent is formed on the base material 1, and the anchor coat layer 2 is formed on the anchor coat layer 2. A gas barrier layer 3 made of a metal oxide is formed therein.

[Polyurethane resin]
As the polyurethane resin constituting the anchor coat layer, a known polyurethane resin that has been conventionally used as the anchor coat layer can be used, but in the present invention, the glass transition temperature (Tg) is 80 ° C. or higher. In particular, it is desirable to use one in the range of 100 to 120 ° C. When the glass transition temperature is lower than the above range, the heat resistance of the anchor coat layer becomes inferior to that in the above range, and the shrinkage rate due to heating between the anchor coat layer and the gas barrier layer becomes inferior. When the difference is generated, the gas barrier layer may be cracked and the barrier property may be deteriorated.

Examples of the polyol component which is the main component of the polyurethane resin include glycols, polyester polyols, polyether polyols, acrylic polyols, and urethane modified products thereof, but it is particularly preferable to use glycols. Examples of the polyester polyol component include a polyester polyol obtained by reacting a polyvalent carboxylic acid or a dialkyl ester thereof or a mixture thereof with glycols or a mixture thereof.
The glass transition temperature of the polyester polyol is preferably −50 to 100 ° C., more preferably −20 ° C. to 80 ° C. The number average molecular weight of these polyester polyols is preferably 10 to 100,000, more preferably 3000 to 80,000.
Examples of the glycol include ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, neopentyl glycol, 1,6-hexanediol and the like.
Examples of the polyvalent carboxylic acid include aromatic polyvalent carboxylic acids such as isophthalic acid, terephthalic acid and naphthalenedicarboxylic acid, and aliphatic polyvalent carboxylic acids such as adipic acid, azelaic acid, sebacic acid and cyclohexanedicarboxylic acid.

As the isocyanate component which is a curing agent for the polyurethane resin, aromatic diisocyanate, aromatic aliphatic diisocyanate, alicyclic diisocyanate, aliphatic diisocyanate and the like can be used.
Examples of the aromatic diisocyanate include tolene diisocyanate (2,4- or 2,6-toluene diisocyanate or a mixture thereof) (TDI), phenylene diisocyanate (m-, p-phenylenediocyanide isocyanate or a mixture thereof), 4,4. ′ -Diphenyldiisocyanate, 1,5-naphthalenediocyanate (NDI), diphenylmethane diisosinate (4,4'-, 2,4'-, or 2,2'-diphenylmethane diisosinate or a mixture thereof) (MDI), Examples thereof include 4,4'-toluene diisocyanate (TODI) and 4,4'-diphenyl ether diisocyanate.
Examples of the aromatic aliphatic diisocyanate include xylene diisocyanate (1,3- or 1,4-xylene diisocyanate or a mixture thereof) (XDI), tetramethylxylene diisocyanate (1,3- or 1,4-tetramethylxylene diisocyanate or (TMXDI), ω, ω'-diisocyanate-1,4-diethylbenzene and the like can be exemplified.

Examples of the alicyclic diisocyanate include 1,3-cyclopentenediisocyanate, cyclohexanediisocyanate (1,4-cyclohexanediisocyanate, 1,3-cyclohexanediisocyanate), 3-isocyanatemethyl-3,5,5-trimethylcyclohexylisocyanate (iso). Holodiisocyanate, IPDI), methylenebis (cyclohexylisocyanate) (4,4'-, 2,4'-or 2,2'-methylenebis (cyclohexylisocyanate)) (hydrogenated MDI), methylcyclohexanediisocyanate (methyl-2,4) -Cyclohexanediisocyanate, methyl-2,6-cyclohexanediisocyanate), bis (isocyanatemethyl) cyclohexane (1,3- or 1,4-bis (isocyanatemethyl) cyclohexane or a mixture thereof) (hydrogenated XDI) and the like. it can.

Examples of the aliphatic diisocyanate include trimethylene diisocyanate, 1,2-propylene diisocyanate, butylene diisocyanate (tetramethylene diisocyanate, 1,2-butylenedylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate) and hexamethylene. Examples thereof include diisocyanate, pendamethylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, and 2,6-diisamethylene methyl caffeate.

The polyisocyanate component is obtained by reacting with a polyfunctional polyisocyanate compound such as isocyanurate, burette, or allophanate derived from the above polyisocyanate monomer, or a trifunctional or higher functional polyol compound such as trimethylolpropane or glycerin. A polyfunctional polyisocyanate compound containing a terminal isocyanate group or the like can also be used.
The polyisocyanate component has a glass transition temperature (Tg) of 50 ° C. or higher and a number average molecular weight (Mn) of 400 or higher, particularly a glass transition temperature (Tg) of 60 ° C. or higher and a number average molecular weight (Mn) of 500 ° C. or higher. Is preferable.
In the present invention, it is preferable to use xylene diisocyanate among the above-mentioned isocyanate components.

[Silane coupling agent]
As the silane coupling agent used for the anchor coat layer, an epoxy silane coupling agent can be preferably used.
Examples of such epoxysilane-based coupling agents include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-. Glycydoxypropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane and the like can be used.
Examples of the silane coupling agent include tetramethoxysilane, tetraethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-isocyanatepropyltriethoxysilane, and the like, which are used as necessary. be able to.

[Composition for forming an anchor coat layer]
In the present invention, the composition for forming the anchor coat layer may be either water-based or solvent-based as long as it contains the polyurethane-based resin and the silane coupling agent, but is preferably an aqueous composition. From the above, it is desirable that the polyurethane resin used is a water-soluble or water-dispersible polyurethane.
In the composition for forming the anchor coat layer, the epoxy silane compound is preferably contained in an amount of 1 to 60 parts by mass with respect to 100 parts by mass (solid content) of the polyurethane resin. When the amount of the epoxy silane compound is less than the above range, the crack resistance during drying cannot be satisfied as compared with the case of the above range, while even if the amount of the epoxy silane compound is larger than the above range, the adhesion is further improved. It is difficult to improve the heat resistance and water resistance may be impaired.

As the aqueous medium, distilled water, ion-exchanged water, pure water and the like can be used as conventionally known aqueous media, and like the known aqueous compositions, organic solvents such as alcohols, polyhydric alcohols and derivatives thereof can be used. Can be contained. When such a co-solvent is used, it can be contained in an amount of 5 to 99% by weight based on the resin content in the aqueous composition. By containing the solvent in the above range, the film forming performance is improved. As such an organic solvent, one having an amphoteric property is preferable, and for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, methyl ethyl ketone, butyl cellosolve, propylene glycol monopropyl ether, ethylene glycol monoblu ether, propylene glycol. Examples thereof include monomethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, 3-methyl 3-methoxybutanol and the like.
In the composition for forming an anchor coat layer, in addition to the above components, known curing accelerators, fillers, softeners, antiaging agents, stabilizers, adhesion accelerators, leveling agents, defoaming agents, plasticizers, and inorganic materials It can also contain fillers, tackifier resins, fibers, colorants such as pigments, and usable time extenders.

(Gas barrier layer)
The gas barrier layer formed on the anchor coat layer formed by the above-mentioned composition for forming an anchor coat layer is formed by containing at least a metal oxide, and it is particularly preferable that the gas barrier layer further contains a phosphoric acid compound.

[Metal oxide]
As the metal oxide, oxides such as aluminum, iron, zirconium, titanium, and silicon can be preferably used, and these oxides can be used alone or in combination of two or more. Examples of the form of the metal oxide include hydrates, oxyhydroxides, oxides, and mixtures thereof.
It is desirable that the metal oxide be used as a dispersion liquid as a slurry of alumina, iron sol, zirconia or the like by a conventionally known hydrolysis condensation or hydrothermal synthesis method. More preferably, these slurries are synthesized and dispersed by heating in the presence of inorganic or organic acids such as nitric acid, hydrochloric acid, perchloric acid, formic acid, acetic acid, citric acid, malic acid and lactic acid. It is desirable to use a dispersion liquid having excellent transparency and viscosity stability. Above all, a dispersion liquid using acetic acid, nitric acid and citric acid can be preferably used. By using such a dispersion liquid, it becomes easy to uniformly disperse the metal oxide in the coating film or the gas barrier layer coating film, and it becomes possible to improve the gas barrier property.

[Phosphate compound]
Phosphoric acid compounds include orthophosphoric acid, polyphosphoric acid, phosphorous acid, phosphoric acid and derivatives thereof. Specific examples of polyphosphoric acid include pyrophosphoric acid, triphosphoric acid, and polyphosphoric acid in which four or more phosphoric acids are condensed. Examples of the above derivatives include orthophosphoric acid, polyphosphoric acid, phosphorous acid, phosphonates, (partial) ester compounds, halides (chlorides and the like), dehydrated products (dilin pentoxide and the like) and the like. Further, in the example of the derivative of phosphonic acid, the hydrogen atom directly bonded to the phosphorus atom of phosphonic acid (HP (= O) (OH) ₂ ) may have various functional groups as an alkyl group. Substituted compounds (eg, nitrilotris (methylenephosphonic acid), N, N, N', N'-ethylenediaminetetrax (methylenephosphonic acid), etc.) and salts thereof, (partial) ester compounds, halides and dehydrations. Things are also included. Further, an organic polymer having a phosphorus atom such as phosphorylated starch can also be used. These phosphoric acid compounds can be used alone or in combination of two or more.

[Composition for forming a barrier layer]
In the present invention, the composition for forming a barrier layer is composed of the above-mentioned metal oxide, preferably further containing a phosphoric acid compound, and as long as it contains these, it may be either an aqueous composition or a solvent-based composition. It is good, but it is preferable that it is an aqueous composition as in the composition for forming an anchor coat layer.
When a phosphoric acid compound is used together with a metal oxide in the composition for forming a barrier layer, the ratio of the metal atom derived from the metal oxide to the phosphorus atom derived from the phosphorus compound is 80:20 to 20:80 (mol). It is desirable that it is in the range of ratio). When the amount of metal atoms is larger than the above range, the metal oxide becomes excessive with respect to the phosphoric acid compound, the bonds between the metal oxide particles become insufficient, and the hydroxyl groups existing on the surface of the inorganic compound The amount may increase and the barrier property and heat resistance may decrease. On the other hand, when the amount of metal atoms is smaller than the above range, the phosphoric acid compound becomes excessive with respect to the metal oxide, the amount of hydroxyl groups derived from the phosphoric acid group increases, and the barrier property and heat resistance may decrease. There is.
When the phosphoric acid compound is contained in the barrier layer forming composition, the phosphoric acid compound and the metal oxide are mixed in a solvent in which the phosphoric acid compound can be dissolved. Since it is preferable that the composition for forming the barrier layer is also an aqueous composition as in the composition for forming the anchor coat layer, the above-mentioned aqueous medium should be used for the composition for forming the anchor coat layer. Is preferable.
In addition to the above components, the barrier layer forming composition may also contain a cross-linking agent, a metal complex, a polymer compound, a filler, a plasticizer, an antioxidant, an ultraviolet absorber, a flame retardant, a colorant and the like. it can.

(Base material)
As the base material for forming the anchor coat layer described above, a conventionally known base material made of a resin such as a thermoplastic resin or a thermosetting resin, a fiber such as paper or a non-woven fabric, or the like can be used, but preferably. , Film, sheet, or bottle-shaped, cup-shaped, tray-shaped, can-shaped, etc. manufactured from thermosetting thermoplastic resin by means such as extrusion molding, injection molding, blow molding, stretch blow molding, or press molding. Any packaging material can be mentioned.

The thermoplastic resin constituting the base material includes low-, medium- or high-density polyethylene, linear low-density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene-copolymer, ionomer, and ethylene-acetate. Olefin-based copolymers such as vinyl copolymers and ethylene-vinyl alcohol copolymers; polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate / isophthalate, and polyethylene naphthalate; nylon 6, nylon 6, 6, nylon 6 , 10, Polyamide such as metaxylylene adipamide; styrene copolymer such as polystyrene, styrene-butadiene block copolymer, styrene-acrylonitrile copolymer, styrene-butadiene-acrylonitrile copolymer (ABS resin); Vinyl chloride-based copolymers such as polyvinyl chloride and vinyl chloride-vinyl acetate copolymers; acrylic copolymers such as polymethylmethacrylate, methylmethacrylate / ethylacrylate copolymers; polycarbonate and the like can be exemplified.
In particular, in the present invention, a sheet made of polyethylene terephthalate, polybutylene terephthalate or polypropylene can be preferably used.

These thermoplastics may be used alone or in the form of a blend of two or more, and the plastic substrate may be in a single layer configuration, for example simultaneous melt extrusion or other lamination. It may have a laminated structure of two or more layers according to the above.
For the melt-moldable thermoplastic resin, one or more of additives such as pigments, antioxidants, antistatic agents, ultraviolet absorbers, and lubricants are added to 100 parts by mass of the resin, if desired. The total amount can be added in the range of 0.001 part to 5.0 part.
Further, for example, in order to reinforce this container, a fiber reinforcing material such as glass fiber, aromatic polyamide fiber, carbon fiber, pulp, cotton linter, or a powder reinforcing material such as carbon black or white carbon, or glass flakes, One type or two or more types of flaky reinforcing materials such as aluminum flakes can be blended in a total amount of 2 to 150 parts by mass with respect to 100 parts by mass of the thermoplastic resin, and for the purpose of further increasing the amount, heavy or heavy One or more of soft calcium carbonate, mica, talc, kaolin, gypsum, clay, barium sulfate, alumina powder, silica powder, magnesium carbonate, etc., as a total amount of 5 to 100 parts by mass of the thermoplastic resin. It can also be formulated in an amount of 100 parts by mass according to a formulation known per se.
Further, for the purpose of improving the gas barrier property, scaly inorganic fine powders such as water-swellable mica, clay and the like are known in an amount of 5 to 100 parts by mass in total with respect to 100 parts by mass of the thermoplastic resin. There is no problem even if it is mixed according to the prescription of.
Similarly, for the purpose of improving the gas barrier property, a thin film layer of an inorganic substance such as silicon oxide or aluminum oxide may be provided on a plastic base material physically or chemically by a vapor deposition method. Absent.

Further, the base material may be a molded product such as a final film, a sheet, or a container, or this coating may be provided in advance on a preformed product for molding into a container. Such preformed bodies include bottomed or bottomless tubular parisons for biaxial stretch blow molding, pipes for plastic molding, vacuum forming, pneumatic forming, sheets for plug-assisted forming, or Examples thereof include a heat seal lid and a film for bag making.

(Manufacturing method of gas barrier laminate)
In the method for producing a gas barrier laminate of the present invention, the above-mentioned composition for forming an anchor coat layer is first applied to at least one surface of the above-mentioned base material.
The coating amount of the composition for forming the anchor coat layer is determined by the contents of the polyurethane resin and the silane coupling agent in the composition, and although it cannot be unconditionally specified, the solid content weight of the coating film is 0.05 to 1. It is preferable to apply the coating so as to be in the range of 00 g / m ² , particularly 0.10 to 0.50 g / m ² . If the amount of anchor coat applied is smaller than the above range, the anchor coat layer may not be adhered to the base material as compared with the case of being in the above range, while if the amount of anchor coat applied is larger than the above range. It becomes inferior in economic efficiency.
The composition for forming an anchor coat layer coated on the substrate removes the solvent in the composition by drying at a temperature of 80 to 140 ° C. for 1 to 60 seconds, although it depends on the composition used and the amount of coating applied. .. As a result, even when the base material is made of a plastic having a low melting point such as polypropylene, the anchor coat layer can be economically formed without affecting it.

Next, the composition for forming a gas barrier layer is applied onto the composition for forming an anchor coat layer in a dry state from which the solvent has been removed. The coating amount of the composition for forming a gas barrier layer is determined by the content of the metal oxide and the phosphoric acid compound in the composition and cannot be unconditionally defined, but is 0.05 to 2.0 g in terms of the solid content weight of the coating film. It is preferable to apply the mixture in the range of / m ² , especially 0.3 to 0.7 g / m ² . If the amount of coating is less than the above range, sufficient barrier properties cannot be obtained. On the other hand, even if the amount of coating is larger than the above range, it is only inferior in economy and has no special merit.
Next, the composition for forming the gas barrier layer is heated at a temperature of 80 to 180 ° C., particularly 120 to 160 ° C. for 1 second to 10 minutes, depending on the composition of the metal oxide in the composition used and the amount of coating. By doing so, a gas barrier layer is formed. This makes it possible to reduce the difference in shrinkage between the gas barrier layer and the anchor coat layer due to heating, improve the crack resistance of the gas barrier layer, and significantly improve the interlayer adhesion between the gas barrier layer and the anchor coat layer. However, even when it is subjected to retort sterilization, the gas barrier layer is prevented from peeling off from the substrate.

The above-mentioned composition for forming an anchor coat layer and the composition for forming a gas barrier layer can be applied, dried or heat-treated by a conventionally known method.
The coating method is not limited to this, and for example, it can be spray-painted, immersed, or coated by a bar coater, a roll coater, a gravure coater, or the like.
Further, the drying or heat treatment can be performed by oven drying (heating), infrared heating, high frequency heating or the like.

(Gas barrier laminate)
The gas barrier laminate of the present invention is formed of a two-layer structure on at least one surface of a base material, particularly a plastic base material, and the anchor coat layer formed on the plastic base material is in close contact with the plastic base material. It is a coating film having excellent properties, and a gas barrier layer made of a metal oxide and a phosphoric acid compound is formed on the coating film.
In the gas barrier laminate produced by the production method of the present invention, the barrier layer itself has sufficient gas barrier performance, particularly oxygen barrier property and water vapor barrier property, and the amount of oxygen permeation before retort (JIS K-7126). (Compliant) is 1.0 cc / m ² · day · atm (under 25 ° C-80% RH environment) and water vapor permeation is 1.0 g / m ² · day · atm (under 40 ° C-90% RH environment) ), Which has excellent gas barrier properties and retort resistance.
Further, the heat resistance and water resistance can be evaluated by evaluating the adhesive force of the gas barrier laminate to the plastic substrate by the T-peel test before and after the retort treatment by the method shown in the examples.

The present invention will be further described by the following examples, but the present invention is not limited by the following examples. The various measurement methods and evaluation methods of Examples and Comparative Examples are as follows.

(Example 1)
[How to make anchor coat paint]
A urethane-based resin emulsion solution (manufactured by Mitsui Chemicals, WPB341, solid content = 30%) was used as the anchor coat paint, and after adjusting the solid content to 6.5% using an aqueous solvent, the urethane-based resin emulsion was used. 3-Glysidoxypropyltrimethoxysilane (LS-2940, manufactured by Shin-Etsu Chemical Co., Ltd.) was added as a silane coupling agent so that the solid content was 10 parts by weight with respect to 100 parts by weight. The anchor coat coating material A-2 was obtained by stirring for a predetermined time and advancing the hydrolysis reaction of the silane coupling agent.
Next, as the barrier coat paint, alumina sol (manufactured by Kawaken Fine Chemicals Co., Ltd., alumina sol 10A, solid content (Al ₂ O ₃ conversion) = 10%) was used as the metal oxide, and the solid content was 3. using a water / methanol solvent. The ratio was adjusted to 6% and the water / methanol ratio was 80/20. Next, as additives, trifluoroacetic acid (Wako Pure Chemical) was added to the solid content of alumina sol (Al ₂ O ₃ equivalent) at 40 phr, and orthophosphoric acid (Wako Pure Chemical, concentration = 85%) was added to the solid content of alumina sol (Al _2). O ₃ basis) was added to a 110phr respect, and a barrier coating composition T-2 to a stirred for a predetermined time.

[Method for preparing gas barrier laminate sample]
The sample of the gas barrier laminate was carried out as follows using the prepared anchor coat paint and barrier coat paint. On a plastic base material with a thickness of 12 μm (manufactured by Toray Film Processing Co., Ltd., Lumirror P60), apply the above-mentioned anchor coat paint to a coating amount of 0.3 g / m ² using a bar coater, and in a box oven at 140 ° C. Drying was performed for -5 seconds. Then, similarly, the above-mentioned barrier coat paint was applied to a coating amount of 0.7 g / m ² using a bar coater, and heat-dried at 180 ° C. for 1 minute in a box oven to obtain a gas barrier laminate. A sample was obtained.

[Method for preparing gas barrier laminated film laminate sample]
The laminated laminate sample for gas barrier property evaluation was a urethane-based adhesive (manufactured by Mitsui Chemicals, Inc., Takenate A-315 / Takenate) having a coating amount of 4.0 g / m ^{2 on} the barrier coat surface of the gas barrier laminate described above. A-50) was applied with a bar coater, dried with a dryer, and then laminated with an unstretched polypropylene film having a thickness of 50 μm to obtain a gas barrier laminated film laminate shown in Example 1.

(Example 2)
In Example 1, the anchor coat paint A-3, the gas barrier laminate, and the gas barrier are used in the same manner as in Example 1 except that 30 phr of 3-glycidoxyepoxysilane is blended as the silane coupling agent for the anchor coat paint. A laminate of sex-laminated film was obtained.

(Example 3)
In Example 1, the anchor coat paint A-4, the gas barrier laminate, and the gas barrier are used in the same manner as in Example 1 except that 60 phr of 3-glycidoxyepoxysilane is blended as the silane coupling agent for the anchor coat paint. A laminate of sex-laminated film was obtained.

(Example 4)
In Example 2, the metal oxide of the barrier coat coating material was iron sol (manufactured by Taki Chemical Industry Co., Ltd., Bailal Fe-C10, solid content (Fe ₂ O ₃ conversion) = 10%), and ortholic acid (Wako Pure Chemical Industries, Ltd., Concentration = 85%) was added so as to be 150 phr with respect to the solid content (Fe ₂ O ₃ conversion) of the iron sol to prepare the barrier coat paint T-1, but the gas barrier lamination was carried out in the same manner as in Example 1. A body and a gas barrier laminate film laminate were obtained.

(Evaluation method)
As shown in Table 3, the evaluation results of the gas barrier laminate and the gas barrier laminate were obtained by using the following evaluation methods.
[Oxygen permeation]
Each gas barrier laminate described in the examples was measured using an oxygen permeation measuring device (OX-TRAN2 / 21 manufactured by Modern Control). The measurement conditions were a temperature of 40 ° C. and a relative humidity of 90%.
[Water vapor permeation amount]
Each gas barrier laminate described in the examples was measured using a water vapor permeation measuring device (PERMATRAN-W 3/31 manufactured by Modern Control). The measurement conditions were a temperature of 40 ° C. and a relative humidity of 90%.
[Retort test]
A pouch (130 cm × 170 cm) was prepared using an impulse sealer (manufactured by Fuji Impulse Co., Ltd., V-301) using a laminate laminate sample prepared using the gas barrier laminate. The obtained pouch was filled with 200 g of pure water. The sample was subjected to a hot water shower retort test at 121 ° C. for 30 minutes to prepare a laminated laminate sample for heat resistance evaluation.
[Measurement method of glass transition temperature Tg]
The glass transition temperature (Tg) of the urethane resin and the anchor coat layer composition was measured using a high-sensitivity differential scanning calorimeter system (DSC6220, manufactured by Hitachi High-Tech Science Co., Ltd.). The measurement was carried out by weighing the coating film on an aluminum pan in a predetermined amount and then measuring at a heating rate of 10 ° C./min.
[T peel strength]
An autograph (AG-IS: manufactured by Shimadzu Corporation) was applied to a sample obtained by applying a urethane adhesive having a coating amount of 4.0 g / m ² to the barrier coat surface of the gas barrier laminate and laminating an unstretched polypropylene film having a thickness of 50 μm. The test force at the time of peeling was measured using. For the peel strength, the test force at the T peel when the peeling width was 15 mm and the test speed was 300 mm / min by sandwiching both sides of the uncoated portion with the adhesive with air chucks was used.

The gas barrier laminate of the present invention has excellent gas barrier properties, has high adhesion to the base material of the gas barrier layer, and has excellent adhesion to the base material even when subjected to retort sterilization treatment. Therefore, it can be suitably used as a packaging material for applications such as retort sterilization treatment.

Claims (6)

A gas barrier characterized by having an anchor coat layer made of a polyurethane resin and a silane coupling agent on at least one surface of the base material, and having a gas barrier layer containing at least a metal oxide on the anchor coat layer. Sex laminate. The gas barrier laminate according to claim 1, wherein the glass transition temperature of the anchor coat layer is 80 ° C. or higher. The gas barrier laminate according to claim 1 or 2, wherein the silane coupling agent is an epoxy silane compound. The gas barrier laminate according to any one of claims 1 to 3, wherein the gas barrier layer is composed of a metal oxide of aluminum and / or iron and a phosphoric acid compound. The gas barrier laminate according to any one of claims 1 to 4, wherein the base material is a film made of polyethylene terephthalate, polybutylene terephthalate, or polypropylene. An anchor coat layer forming composition containing a polyurethane resin and a silane coupling agent was applied to at least one surface of the base material, and the anchor coat layer forming composition was subjected to a drying treatment to remove the solvent. After that, a composition for forming a gas barrier layer containing a metal oxide and a phosphoric acid compound is applied onto the composition for forming an anchor coat layer, and then the composition is subjected to heat treatment to form an anchor coat layer and a gas barrier layer. The method for producing a gas barrier laminate according to any one of claims 1 to 5, wherein the gas barrier laminate is produced.