JP6838300B2 - Laminated film - Google Patents

Description

The present invention relates to a laminated film. More specifically, the present invention relates to a laminated film which has a small environmental load during manufacturing and disposal, and has both excellent gas barrier properties in a high humidity environment and sufficient adhesive strength as a packaging material.

Packaging materials used in foods, pharmaceuticals, industrial products, etc. have the property of blocking gases such as oxygen and water vapor, that is, gas barrier properties, in order to suppress oxidation of proteins and fats and oils, maintain taste and freshness, and maintain the efficacy of pharmaceuticals. Is required to be provided. Further, gas barrier materials used for electronic devices such as solar cells and organic ELs and electronic parts often require higher gas barrier properties than packaging materials such as foods.

Among them, polypropylene film is widely used in a wide range of applications such as packaging of foods and various products, electrical insulation, and surface protection film. By using this polypropylene film, due to the characteristics of the same material, it is possible to exhibit a higher water vapor barrier property than, for example, a polyamide film made of nylon 6 or the like or a polyester film made of polyethylene terephthalate or the like. However, the polypropylene film has a problem that the oxygen barrier property is lower than that of a general polyamide film or polyester film.

Conventionally, a film obtained by laminating a polymer resin composition such as polyvinylidene chloride resin or polyacrylonitrile, which is generally said to have a relatively high oxygen barrier property, on a polypropylene film has been used (see, for example, Patent Document 1). ..
However, polyvinylidene chloride resin and polyacrylonitrile have low humidity dependence and show good gas barrier properties, but have a problem that there is a high risk of generating harmful substances during disposal and incineration.

Further, a film obtained by laminating a polymer resin composition having a relatively high oxygen barrier property such as polyvinyl alcohol or ethylene vinyl alcohol copolymer on a polypropylene film has been used (see, for example, Patent Documents 2 and 3). ).
However, since the film on which the polymer resin composition of the above polyvinyl alcohol or ethylene vinyl alcohol copolymer is laminated has a large humidity dependence, there is a problem that the gas barrier property is deteriorated under high humidity.

A film in which a resin layer containing a silane coupling agent in a vinyl alcohol-based resin is laminated on a base film has been proposed. In this case, since the vinyl alcohol-based resin is crosslinked by the silane coupling agent, the humidity dependence is low and a good gas barrier property is exhibited (see, for example, Patent Documents 4 and 5).

However, these laminated films require sufficient heat treatment for cross-linking, and cannot satisfy sufficient properties as a packaging material due to deterioration of mechanical properties of the polypropylene film as a base material and thermal wrinkles during processing. .. In addition, a large amount of energy is required during the heat treatment during processing, which is not preferable from the viewpoint of environmental load.

A film in which a resin layer containing inorganic layered particles having a specific particle size and aspect ratio is laminated on polyvinyl alcohol has been proposed. In this case, the inorganic layered particles dispersed in the resin layer cause a detour effect of gas molecules, and exhibit a good gas barrier property (see, for example, Patent Document 6).

However, in these laminated films, the inorganic layered particles hinder the adhesiveness with the polypropylene film, the laminating strength is lowered, and sufficiently satisfactory performance has not been obtained.

A film in which a resin layer containing a urethane resin is laminated has been proposed. In this case, since it contains a urethane group or a urea group, it has good adhesiveness to the base material (see, for example, Patent Document 7).

However, these laminated films are inferior in gas barrier properties to the above-mentioned polyvinylidene chloride resin laminated polypropylene film, and sufficiently satisfactory performance has not been obtained.

Further, a gas barrier composite film having a base film layer and a resin layer in which inorganic layered particles are contained in a urethane resin has been proposed. In this case, although good gas barrier properties were exhibited, the inorganic layered particles hindered the adhesion to the base film, the laminate strength was lowered, and sufficiently satisfactory performance was not obtained (see, for example, Patent Document 8). .).

A gas barrier film including a resin base film and a film composed of an aqueous polyurethane resin, inorganic layered particles, a polyvinyl alcohol resin, and a curing agent has been proposed. In this case, the cohesive strength of the resin layer is improved by cross-linking with the polyvinyl alcohol resin and the curing agent, and the adhesiveness to the base film is improved (see, for example, Patent Document 9).

However, since it contains a polyvinyl alcohol resin having a high humidity dependence on the gas barrier property and a cross-linking agent that inhibits the gas barrier property, sufficient gas barrier property cannot be satisfied. Further, when polypropylene is used as a base material, the gas barrier property is deteriorated and the laminate strength is lowered due to dimensional changes such as expansion and contraction of the base material that occur over time, and there is a problem that sufficient adhesiveness to the base material cannot be satisfied. There was a point.

That is, the above-mentioned prior art is an excellent gas barrier in which, when a polypropylene film is used as a base film, there is little deterioration in mechanical properties and thermal wrinkles of the base film during production of a laminated film, and humidity dependence and deterioration over time are extremely small. It has not provided a laminated film that satisfies both properties at the same time with sufficient properties and sufficient adhesiveness to the base film.

Japanese Unexamined Patent Publication No. 2003-231221 Japanese Unexamined Patent Publication No. 2000-52501 Japanese Unexamined Patent Publication No. 4-359033 Japanese Unexamined Patent Publication No. 4-345841 Japanese Unexamined Patent Publication No. 2006-95782 Japanese Unexamined Patent Publication No. 7-251475 Japanese Unexamined Patent Publication No. 2005-139435 Japanese Unexamined Patent Publication No. 2001-98047 Japanese Unexamined Patent Publication No. 2015-85546

An object of the present invention has been made to solve the above problems, that is, a laminated film having both excellent gas barrier properties in a high humidity environment and sufficient adhesive strength of a coating layer to a base film. Is to provide.

As a result of diligent research in order to solve the above problems, the present inventors have finally completed the present invention. That is, the present invention is as follows.

The first invention is a laminated film having a coating layer on at least one surface of a base film, the base film is an oriented film mainly composed of a propylene-based polymer, and the coating layer is a diisocyanate component. It contains at least a water-dispersible polyurethane resin composed of at least one selected from range isocyanate and hydrogenated xylylene range isocyanate and inorganic layered particles, and is laminated with the heat shrinkage rate A of the base film at 120 ° C. of the laminated film. The laminated film is characterized in that the difference (AB) in the heat shrinkage rate B of the film is 0.3% or more and 3.0% or less in both the MD direction and the TD direction.
The second invention relates to the first invention in which the base film is an oriented film mainly composed of a propylene-based polymer satisfying the following requirements (a) to (c) and also satisfies the following requirement (d). The laminated film described.
(A) Mesopentad fraction of 96% or more (b) Content of comonomer other than propylene is 0.5 mol% or less (c) Melt flow rate (MFR) is 0.5 g / 10 minutes or more, 20 g / 10 minutes or less ( d) The half-value width of the maximum peak when the scattering intensity of 110 planes of polypropylene α-type crystal measured by the wide-angle X-ray scattering method is plotted against the azimuth angle is 30 degrees or less. The laminated film according to either the first or second invention, wherein the long-period size obtained from the long-period scattering peak in the main orientation direction measured by the small-angle X-ray scattering method of the film is 40 nm or more.
In the fourth invention, the average particle size of the inorganic layered particles is 2.0 μm or more and 6.5 μm or less, and the content of the inorganic layered particles is 4% by mass or more and 20% by mass or less. The laminated film according to any one of the inventions.
The fifth invention is the laminated film according to any one of the first to fourth inventions, wherein the heat shrinkage ratios of the laminated film in the MD direction and the TD direction at 120 ° C. are both 1.0% or less.
The sixth invention is the laminated film according to any one of the first to fifth inventions, wherein the haze of the laminated film is 5.0% or less.
The seventh invention is the method for producing a laminated film according to the first to sixth inventions, which is water-dispersible in which the diisocyanate component is composed of at least one selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate. A step of applying a coating liquid containing at least a polyurethane resin, inorganic layered particles, and a solvent to a propylene-based polymer-oriented film to form a coating layer, and then adjusting the tension of the propylene-based polymer-oriented film to 30 N / m or more and 150 N / m. The present invention is characterized by comprising a step of volatilizing the solvent contained in the coating layer to form a coating layer while maintaining the temperature of the propylene-based polymer-oriented film in the range of 60 ° C. or higher and 150 ° C. or lower. This is a method for producing a laminated film.
The eighth invention is a laminate in which an adhesive layer and a thermosetting resin layer are sequentially laminated on the coating layer of the laminated film according to any one of the first to sixth inventions.
A ninth invention is a laminated film roll made of the laminated film according to any one of the first to sixth inventions.
A tenth invention is the method for producing a laminated film roll according to a ninth invention, in which a diisocyanate component is a water-dispersible polyurethane composed of at least one selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate. A step of applying a coating liquid containing at least a resin, inorganic layered particles, and a solvent to a propylene-based polymer-oriented film to form a coating layer, and then adjusting the tension of the propylene-based polymer-oriented film to 30 N / m or more and 150 N / m or less. In addition, a step of forming a coating layer by volatilizing the solvent contained in the coating layer while maintaining the temperature of the propylene-based polymer orientation film in the range of 60 ° C. or higher and 150 ° C. or lower, and the coating layer were formed. It is a method for producing a laminated film roll, which comprises a step of winding a laminated film.

The laminated film of the present invention has both excellent gas barrier properties and sufficient adhesive strength in a high humidity environment. Since the present invention has high gas barrier properties and excellent adhesive strength of the coating layer to the base film, it can be suitably used as a packaging material for foods, pharmaceuticals, industrial products and the like.

Relationship between the difference in heat shrinkage (AB) in the MD direction and the content of inorganic layered particles in Example 1, Example 9, Example 10, Example 11, Example 12, and Comparative Example 3. Relationship between heat shrinkage rate difference (AB) in the MD direction and oxygen permeability in Example 1, Example 9, Example 10, Example 11, Example 12, and Comparative Example 3. Relationship between heat shrinkage rate difference (AB) in the MD direction and laminate strength in Example 1, Example 9, Example 10, Example 11, Example 12, and Comparative Example 3. Relationship between the difference in heat shrinkage B in the MD direction and the content of inorganic layered particles in Example 1, Example 9, Example 10, Example 11, Example 12, and Comparative Example 3.

Hereinafter, the present invention will be described in detail.

In the laminated film of the present invention, the difference (AB) between the heat shrinkage rate A of the base film and the heat shrinkage rate B of the laminated film is different in the heat shrinkage rate in the MD direction and the TD direction of the laminated film at 120 ° C. It is important that both are 0.3% or more and 3.0% or less. Further, the lower limit is preferably 0.5% or more, and the upper limit is preferably 1.0% or less.
When this heat shrinkage rate (AB) is smaller than 0.3%, it is not possible to suppress the gap through which oxygen molecules generated by the invasion of water molecules into the coating layer, and oxygen in a high humidity environment cannot be suppressed. Barrier property is not fully expressed.
Here, the MD direction is the flow direction of the film (sometimes referred to as the length direction or the longitudinal direction), and the TD direction is the direction perpendicular to the flow direction of the film (referred to as the lateral direction or the width direction). There is also).

Conventionally, it has been considered desirable to actively introduce a crosslinked structure from the viewpoint of improving the oxygen barrier property in a high humidity environment, but in the present invention, the heat shrinkage rate A of the base film and the laminated film It was found that the barrier property in an oxygen-high humidity environment is improved by setting the difference in heat shrinkage rate B (AB) within the above range. The inventor considers the influence of the coating layer on the heat shrinkage difference (AB) as follows.

The shrinkage stress generated in the base film and the coating layer in the process of forming the coating layer was considered. Shrink stress acts on the base film due to the heat applied in the process of forming the coating layer on the base film. If the coating layer is more flexible than the base film, the effect of the coating layer on the shrinkage of the base film is small, so that the residual stress of the base film after the coating layer is formed is small, and therefore the difference in heat shrinkage (A). −B) also becomes smaller. On the other hand, when inorganic layered particles are blended in the coating layer, the elastic modulus of the coating layer becomes high and the effect of suppressing the shrinkage of the base film by the coating layer is large, so that the residual stress of the base film after the coating layer is formed is large. Is large, and it is estimated that the difference in thermal shrinkage (AB) is also large.
By controlling the difference in heat shrinkage (AB) to a specific range, the decrease in gas barrier property in a high humidity environment is reduced. It is estimated that the gap at the molecular level through which oxygen molecules generated by water molecules in the atmosphere that have invaded the coating layer, which exist at the interface with the layered particles, can pass is reduced.
On the other hand, when the heat shrinkage rate difference (AB) exceeds 3.0%, the shrinkage stress difference generated at the interface between the base film and the coating layer becomes large, so that the laminate strength is lowered.

In the laminated film of the present invention, the heat shrinkage rate B of the laminated film is preferably 1.0% or less in both the MD direction and the TD direction of the laminated film at 120 ° C. When the heat shrinkage rate B exceeds 1.0%, the laminated film is formed in the case of the drying process at the time of laminating the printing layer or the laminating layer, or in the case of the heating process at the time of bag processing when used as a packaging material. It may shrink, reducing workability and impairing the quality of the packaging material.

The laminated film of the present invention has excellent gas barrier properties. Specifically, it is preferable that the oxygen permeability (OTR) is 150 ml / m ² · day · MPa or less and the water vapor permeability (WVTR) is 5.0 g / m ² · day or less. Further, the oxygen permeability (OTR) is ^{preferably 100 ml / m 2} · day · MPa or less, particularly preferably 50 ml / m ² · day · MPa or less, and the water vapor permeability (WVTR) is 4.5 g / m ² · day. Hereinafter, in particular, it is preferably ^{4.0 g / m 2 · day.} Here, the oxygen permeability (OTR) is a value measured under the conditions of 20 ° C. and 80% RH according to the JIS K7126-2A method. The water vapor permeability (WVTR) is a value measured under the conditions of 40 ° C. and 90% RH according to the JIS K7129-B method.

The laminated film of the present invention is excellent in laminating adhesive strength. Specifically, the lamination strength is preferably 2.0 N / 15 mm or more, and more preferably 2.5 N / 15 mm or more. If the lamination strength is less than 2.0 N / 15 mm width, the laminated film may peel off when used as a packaging material, and the contents may not be sufficiently protected. The evaluation of the laminate strength in the present invention was carried out as follows. Urethane-based two-component curable adhesive (Mitsui Chemicals "Takelac A525S" and "Takenate A50" mixed at a ratio of 13.5: 1 (mass ratio)) on the coating layer of the laminated film by dry lamination processing) An unstretched polypropylene film having a thickness of 30 μm (“P1128” manufactured by Toyobo Co., Ltd.) was laminated and aged at 40 ° C. for 4 days to obtain a laminate for evaluation. The thickness of the adhesive layer formed of the urethane-based two-component curable adhesive after drying was about 4 μm. The obtained laminated laminate was cut into a test piece having a width of 15 mm and a length of 200 mm, and under the conditions of a temperature of 23 ° C. and a relative humidity of 65%, a Tensilon universal material tester (“Tensilon UMT-II-” manufactured by Toyo Boldwin Co., Ltd. The laminate strength (normal state) was measured using "500 type"). The tensile speed at the time of measuring the laminate strength was 200 mm / min, and the tensile direction was 90 ° peeling.

When the laminated film of the present invention is used as a packaging material, it is preferably transparent from the viewpoint of visibility of the contents. Specifically, the haze is preferably 5.0% or less, more preferably 4.0% or less. Here, the evaluation of haze was based on JIS K7136, and was measured using a turbidity meter (NDH2000, manufactured by Nippon Denshoku Co., Ltd.).

The components of the present invention will be described below.
(Coating layer)
The laminated film of the present invention is one in which a coating layer is directly laminated on at least one side of a base film. In the present invention, the coating layer has an oxygen gas barrier property superior to that of the base film, and has excellent adhesion to the base film and an ink layer or an adhesive layer laminated on the coating layer. It is a layer having sex. By having the coating layer, the laminated film of the present invention has a gas barrier property having an oxygen permeability (OTR) of 150 ml / m2 · day · MPa or less and a steam permeability (WVTR) of 5.0 g / m2 · day or less. It has an adhesive strength of 2.0 N / 15 mm width or more, and can be suitably used as a packaging material for, for example, foods, pharmaceuticals, and industrial products.

(Polyurethane resin)
It is important that the coating layer used in the present invention contains a water-dispersible polyurethane resin as a main component, wherein the diisocyanate component is composed of at least one selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate. Unlike polyvinylidene chloride resin, this polyurethane resin has less risk of generating harmful substances during disposal and incineration, and is excellent with the base film and the ink layer and adhesive layer laminated on the coating layer. It is suitable because it can have adhesiveness.

The polyurethane resin used for the coating layer in the present invention contains at least a polyol component and a polyisocyanate component as constituent components, and further contains a chain extender, if necessary. The polyurethane resin in the present invention is a polymer compound in which these constituent components are copolymerized mainly by urethane bonds.

Polyester components include polyvalent carboxylic acids (eg, malonic acid, succinic acid, adipic acid, sebacic acid, fumaric acid, maleic acid, terephthalic acid, isophthalic acid, etc.) or their acid anhydrides and polyhydric alcohols (eg, eg. Reaction of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, neopentyl glycol, 1,6-hexanediol, etc.) Examples thereof include polyester polyols obtained from, polyethylene glycol, polypropylene glycol, polyethylene propylene glycol, polytetramethylene ether glycol, polyether polyols such as polyhexamethylene ether glycol, polycarbonate polyols, polyolefin polyols, acrylic polyols and the like. In particular, the use of a low molecular weight polyol component increases the urethane group ratio and improves the cohesive force due to hydrogen bonds, thus improving the barrier property.

It is important that the diisocyanate component, which is a component of the polyurethane resin used for the coating layer in the present invention, is composed of at least one selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate. By being composed of the diisocyanate component, the gas barrier property of the coating layer is improved. When the cyclic portion has a substituent, the side chains of the aromatic ring and the alicyclic are preferably short chains. Further, it is more preferable that the diisocyanate component has symmetry because the cohesive force is improved.

The diisocyanate component, which is a constituent component of the polyurethane resin used for the coating layer in the present invention, is an object of the present invention for the purpose of improving the adhesiveness with the ink layer and the adhesive layer laminated on the base film and the coating layer. A polyisocyanate component may be contained in addition to at least one diisocyanate selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate as long as the above is not impaired. For example, aromatic diisocyanates such as tolylene diisocyanate and diphenylmethane-4,4-diisocyanate, isophorone diisocyanate and 4,4-dicyclohexylmethane diisocyanate, alicyclic diisocyanates such as 1,3-bis (isocyanatemethyl) cyclohexane, and hexa. Examples thereof include aliphatic diisocyanates such as methylene diisocyanate and 2,2,4-trimethylhexamethylene diisocyanate, and polyisocyanates in which a single or a plurality of these compounds are added in advance with trimethylolpropane or the like.

As the coating layer used in the present invention, it is preferable to use an aqueous coating liquid from the viewpoint of reducing the environmental load during production. Therefore, it is desirable that the polyurethane resin of the present invention is water-dispersible. The above-mentioned "water dispersibility" means that an emulsion is formed in water or an aqueous solution containing less than 50% by mass of a water-soluble organic solvent and dispersed in the solvent.

In order to impart water solubility to the polyurethane resin used for the coating layer in the present invention, a sulfonic acid (salt) group or a carboxylic acid (salt) group can be introduced (copolymerized) into the urethane molecular skeleton. Since the sulfonic acid (salt) group is strongly acidic and it may be difficult to maintain moisture resistance due to its hygroscopic performance, it is preferable to introduce a weakly acidic carboxylic acid (salt) group. It is also possible to introduce a nonionic group such as a polyoxyalkylene group.

In order to introduce a carboxylic acid (salt) group into a polyurethane resin, for example, as a polyol component, a polyol compound having a carboxylic acid group such as dimethylolpropionic acid or dimethylolbutanoic acid is introduced as a copolymerization component to form a salt. Neutralize with agent. Specific examples of the salt forming agent include trialkylamines such as ammonia, trimethylamine, triethylamine, triisopropylamine, tri-n-propylamine and tri-n-butylamine, and N such as N-methylmorpholin and N-ethylmorpholin. Examples thereof include N-dialkylalkanolamines such as −alkylmorpholins, N-dimethylethanolamine and N-diethylethanolamine. These can be used alone or in combination of two or more.

When a polyol compound having a carboxylic acid (salt) group is used as a copolymerization component in order to impart water solubility, the composition molar ratio of the polyol compound having a carboxylic acid (salt) group in the polyurethane resin is that of the polyurethane resin. When the total polyisocyanate component is 100 mol%, it is preferably 3 to 60 mol%, preferably 5 to 40 mol%. If the composition molar ratio is less than 3 mol%, water dispersibility may become difficult. If the composition molar ratio exceeds 60 mol%, the water resistance may decrease and the gas barrier property may decrease in a high humidity environment.

Two or more types of polyurethane resins used for the coating layer in the present invention may be contained in order to improve the adhesiveness between the base film and the ink layer or adhesive layer laminated on the coating layer.

The coating layer in the present invention includes a non-polyurethane resin as long as the object of the present invention is not impaired for the purpose of improving the adhesiveness between the base film and the ink layer and the adhesive layer laminated on the coating layer. Resin may be contained. For example, acrylic resin, polyester resin and the like can be mentioned.

(Inorganic layered particles)
It is important that the coating layer in the present invention contains inorganic layered particles. Unlike a coating layer containing a cross-linking agent, it does not require high-temperature heat treatment during cross-linking, and it is possible to reduce deterioration of mechanical properties of the base film due to heat and thermal wrinkles during processing, and as a packaging material. Suitable. Further, in the present invention, the inclusion of inorganic layered particles suppresses the shrinkage of the coating layer, and makes it possible to exhibit excellent gas barrier properties with extremely small humidity dependence and aging deterioration, which were difficult with conventional techniques. ..

The inorganic layered particles used for the coating layer in the present invention are inorganic compounds in which ultrathin unit crystal layers are stacked to form one layered particle, for example, mica, kaolinite, montmorillonite, and vercu. Examples include light, smectite, antigolite, and talc. These inorganic layered particles may be used alone or in admixture of two or more.

The coating layer of the present invention is preferably formed by using an aqueous coating liquid from the viewpoint of reducing the environmental load during production. Therefore, the inorganic layered particles of the present invention are preferably inorganic layered particles having swelling property in water, and more preferably mica group clay minerals such as swelling mica. By using the inorganic layered particles having swelling property in water, the polyurethane resin can penetrate between the layers of the inorganic layered particles swollen in water, and the gas barrier property can be improved.

The average particle size of the inorganic layered particles used in the coating layer in the present invention is preferably 2.0 μm or more and 6.5 μm or less, further preferably the lower limit is 3.0 μm or more and the upper limit is 5.0 μm or less. When the average particle size of the particles is smaller than 2.0 μm, the average particle size is too small, so that the effect of developing gas barrier properties due to the detour effect of gas molecules is small, and the shrinking force exerted by the base film on the coating layer is small. Therefore, it is easily affected by humidity dependence and deterioration of gas barrier property over time. On the other hand, when it exceeds 6.5 μm, since the particle size is large, surface protrusions due to inorganic layered particles are generated on the surface of the coating layer, so that the transparency is lowered and the sealant film is laminated on the coating layer via the adhesive layer. At that time, air bubbles are generated in the adhesive layer due to the difference in wettability between the surface protrusions and the non-protrusions, which impairs the appearance after lamination. The average particle size was diluted with ion-exchanged water so that the content of the inorganic layered particles was 0.05% by mass, and a laser diffraction type particle size distribution meter (SALD-7500 manufactured by Shimadzu Corporation) was used. , The particle size distribution was measured. The average value of the particle size distribution was calculated and used as the average particle size.

The content of the inorganic layered particles used in the coating layer in the present invention in the coating layer is preferably 4% by mass or more and 20% by mass or less, further, the lower limit is 5% by mass or more and the upper limit is 15% by mass or less. Is preferable. When the content of the particles is less than 4% by mass, the effect of developing the gas barrier property due to the detour effect of the gas molecules becomes small.
Further, it is unpredictable that when the content of the inorganic layered particles in the coating layer is 4% by mass or more, the heat shrinkage rate difference (AB) becomes 0.3% or more, which depends on the high humidity environment. It is less susceptible to the effects of reduced gas barrier properties. On the other hand, when it exceeds 20% by mass, the transparency is lowered because the content is large.

In FIG. 1, when the same type of base film S1 is used in Examples and Comparative Examples and the content of the inorganic layered compound in the coating layer is changed (Example 1, Example 9, Example 10, Example). The relationship between the difference in heat shrinkage rate (AB) in the MD direction and the content of the inorganic layered particles in 11, Example 12, and Comparative Example 3) is shown in FIG. 1. The larger the content of the inorganic layered particles, the higher the heat shrinkage rate. The difference (AB) is large.

Similarly, the relationship between the heat shrinkage rate difference (AB) and the oxygen permeability is shown in FIG. 2. The larger the heat shrinkage rate difference (AB), the smaller the oxygen permeability.

Similarly, the relationship between the heat shrinkage rate difference (AB) and the laminate strength is shown in FIG. 3. The smaller the heat shrinkage rate difference (AB), the higher the laminate strength.

Similarly, the relationship between the heat shrinkage difference B and the content of the inorganic layered particles is shown in FIG. 4, but the correlation between the heat shrinkage B of the laminated film and the content of the inorganic layered particles and the oxygen permeability is not clear. There wasn't.

In order to impart other functionality to the coating layer, various additives may be contained as long as the object of the present invention is not impaired. Examples of the additive include surfactants, fluorescent dyes, fluorescent whitening agents, plasticizing agents, ultraviolet absorbers, pigment dispersants, defoaming agents, defoaming agents, preservatives, antistatic agents and the like.

In the present invention, as a method of providing the coating layer on the base film, a method of applying a coating liquid containing a solvent, inorganic layered particles, and a polyurethane resin on the base film and drying it can be mentioned. Examples of the solvent include an organic solvent such as toluene, water, or a mixed system of water and a water-soluble organic solvent. From the viewpoint of environmental problems, water alone or a mixture of water and a water-soluble organic solvent is preferable.

From the viewpoint of heat resistance of the polypropylene film used as the base material, it may be necessary to adjust the drying temperature after coating to 150 ° C or lower. Therefore, the boiling point of the organic solvent constituting the coating liquid is 50 ° C or higher and 150 ° C or lower. Is preferable. Specific examples include alcohol solvents such as methanol, ethanol and isopropyl alcohol, acetate solvents such as methyl acetate, ethyl acetate and butyl acetate, ketone solvents such as acetone and methyl ethyl ketone, and aromatic solvents such as toluene. , Cyclic ether solvent such as dioxane and the like. These solvents may be used alone or in combination of two or more.

In the present invention, the coating layer is preferably formed by applying a coating liquid containing a solvent, inorganic layered particles, and a polyurethane resin onto a base film and drying it.

(Base film)

In the present invention, the polypropylene film used as the base film preferably has heat resistance.
Here, having heat resistance means that the difference (AB) between the heat shrinkage rate A of the base film and the heat shrinkage rate B of the laminated film at 120 ° C. of the laminated film is 0.3% in both the MD direction and the TD direction. As mentioned above, it means that it has heat shrinkage characteristics suitable for 3.0% or less. The higher the heat shrinkage rate, the larger the difference in heat shrinkage rate (AB) tends to be, but the difference in heat shrinkage rate B (AB) is 0.3% or more in both the MD direction and the TD direction. It may be designed to be 3.0% or less.
On the other hand, the smaller the heat shrinkage rate, the less defects such as cracks and deformations occur in the coating layer, printing layer, and laminated layer laminated on the base film, and the film heat that can maintain the quality and efficacy of the contents as a packaging material. It has characteristics.

In the present invention, it is important that the resin composition constituting the base film is a polypropylene-based resin. By using a polypropylene-based resin, it is possible to have a higher water vapor barrier property than a polyamide film made of nylon 6 or the like or a polyester film made of polyethylene terephthalate or the like, and it can be suitably used as a food packaging material.

The polypropylene-based resin used in the present invention is not particularly limited, and for example, a propylene homopolymer or a copolymer with ethylene and / or an α-olefin having 4 or more carbon atoms can be used.

In the present invention, the polypropylene resin constituting the base film is preferably a propylene homopolymer containing substantially no comonomer, and even when a comonomer is contained, the amount of comonomer is 0.5 mol% or less. Is preferable. The upper limit of the amount of comonomer is more preferably 0.3 mol%, still more preferably 0.1 mol%. Within the above range, the crystallinity is improved, the heat shrinkage rate at high temperature is reduced, and the heat resistance is improved. In addition, a comonomer may be contained as long as it is a trace amount within a range that does not significantly reduce the crystallinity.

The polypropylene resin constituting the base film is more preferably a propylene homopolymer obtained only from a propylene monomer, and even if it is a propylene homopolymer, it does not contain a heterogeneous bond such as a head-to-head bond. Most preferred.

In the present invention, as the polypropylene resin constituting the base film, the lower limit of the mesopentad fraction measured by ^{13 C-NMR, which is an index of the stereoregularity of the polypropylene resin, is preferably 96%.} The lower limit of the mesopentad fraction is more preferably 96.5% and even more preferably 97%. Within the above range, the crystallinity is improved, the heat shrinkage rate at high temperature is smaller, and the heat resistance is improved. The upper limit of the mesopentad fraction is preferably 99.8%, more preferably 99.6% and even more preferably 99.5%. Within the above range, realistic manufacturing becomes easy.

The lower limit of the meso-average chain length of the polypropylene resin constituting the base film is preferably 100, more preferably 120, and even more preferably 130. Within the above range, the crystallinity is improved, the heat shrinkage rate at high temperature is smaller, and the heat resistance is improved. The upper limit of the meso average chain length is preferably 5000 from a practical point of view.

From a practical point of view, the lower limit of the xylene-soluble content of the polypropylene resin constituting the base film is preferably 0.1% by mass. The upper limit of the xylene-soluble content is preferably 7% by mass, more preferably 6% by mass, and further preferably 5% by mass. Within the above range, the crystallinity is improved, the heat shrinkage rate at high temperature is smaller, and the heat resistance is improved.

In the present invention, the lower limit of the melt flow rate (MFR) (230 ° C., 2.16 kgf) of the polypropylene resin constituting the base film is preferably 0.5 g / 10 minutes. The lower limit of MFR is more preferably 1.0 g / 10 minutes, further preferably 2.0 g / 10 minutes, particularly preferably 4.0 g / 10 minutes, and most preferably 6.0 g / 10 minutes. Is. Within the above range, the mechanical load is small and extrusion and stretching become easy. The upper limit of MFR is preferably 20 g / 10 minutes. The upper limit of MFR is more preferably 17 g / 10 minutes, further preferably 16 g / 10 minutes, and particularly preferably 15 g / 10 minutes. Within the above range, stretching becomes easy, thickness unevenness becomes small, the stretching temperature and heat fixing temperature are easily raised, the heat shrinkage rate becomes smaller, and heat resistance is improved.

The lower limit of the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) of the polypropylene resin constituting the base film is preferably 20000, more preferably 22000, and further preferably 24000. It is particularly preferably 26,000 and most preferably 27,000. Within the above range, stretching becomes easy, thickness unevenness becomes small, the stretching temperature and heat fixing temperature are easily raised, the heat shrinkage rate becomes smaller, and heat resistance is improved. The upper limit of Mn is preferably 200,000, more preferably 170000, still more preferably 160000, and particularly preferably 150,000. Within the above range, the effects of the present application such as low heat shrinkage at high temperature, which is the effect of low molecular weight substances, can be easily obtained, and stretching becomes easy.

The lower limit of the mass average molecular weight (Mw) measured by the GPC of the polypropylene resin constituting the base film is preferably 180,000, more preferably 200,000, still more preferably 230000, and further preferably 240000. , Particularly preferably 250,000 and most preferably 270000. Within the above range, stretching becomes easy, thickness unevenness becomes small, the stretching temperature and heat fixing temperature are easily raised, the heat shrinkage rate becomes smaller, and heat resistance is improved. The upper limit of Mw is preferably 500,000, more preferably 450,000, further preferably 420,000, particularly preferably 410000, and most preferably 400,000. Within the above range, the mechanical load is small and extrusion and stretching are easy.

In the present invention, the polypropylene resin used for the base film preferably has the following characteristics. That is, when the gel permeation chromatography (GPC) integration curve of the polypropylene resin constituting the film is measured, the lower limit of the amount of the component having a molecular weight of 100,000 or less is preferably 35% by mass, more preferably 38% by mass. It is more preferably 40% by mass, particularly preferably 41% by mass, and most preferably 42% by mass. Within the above range, the effects of the present application such as low heat shrinkage at high temperature, which is the effect of low molecular weight substances, can be easily obtained, and stretching becomes easy. The upper limit of the amount of the component having a molecular weight of 100,000 or less in the GPC integration curve is preferably 65% by mass, more preferably 60% by mass, further preferably 58% by mass, and particularly preferably 56% by mass. , Most preferably 55% by mass. Within the above range, stretching becomes easy, thickness unevenness becomes small, the stretching temperature and heat fixing temperature are easily raised, the heat shrinkage rate becomes smaller, and heat resistance is improved.

In the present invention, the polypropylene resin used for the base film generally has a lower limit of mass average molecular weight (Mw) / number average molecular weight (Mn), which is an index of the breadth of molecular weight distribution, preferably 4. It is preferably 4.5, more preferably 5, particularly preferably 5.5, and most preferably 6. The upper limit of Mw / Mn is preferably 30, more preferably 25, still more preferably 22, particularly preferably 21, and most preferably 20. When Mw / Mn is in the above range, realistic production is easy. Regarding the molecular weight distribution of polypropylene, components with different molecular weights are polymerized in a series of plants in multiple stages, components with different molecular weights are blended offline with a kneader, and catalysts with different performances are blended and polymerized. It can be adjusted by using a catalyst capable of achieving a desired molecular weight distribution.

In the present invention, the polypropylene film used as the base film has a degree of crystal orientation that varies depending on the molecular structure of the polypropylene used and the process and conditions in film production. Further, the orientation direction of the stretched polypropylene film can be determined by incident X-rays perpendicularly to the film surface by a wide-angle X-ray diffraction method and measuring the azimuth angle dependence of the scattering peak derived from the crystal. it can. Specifically, the stretched polypropylene film typically has a monoclinic α-type crystal structure. The α-type crystal has a strong orientation mainly in one axis when the azimuth dependence of the scattering intensity of 110 planes (plane spacing: 6.65 angstroms) is measured by a wide-angle X-ray diffraction method. That is, when the scattering intensity derived from the 110th plane of the α-type crystal is plotted against the azimuth angle, the strongest peak is observed in the direction perpendicular to the orientation of the molecular axis. In the present invention, the degree of orientation is defined by the full width at half maximum of this maximum peak.

In the polypropylene film used as the base material of the present invention, it is preferable that the half width of the maximum peak when the scattering intensity of 110 planes measured by the wide-angle X-ray scattering method is plotted against the azimuth is 30 degrees or less. The upper limit of this half width is more preferably 29 degrees, still more preferably 28 degrees. If the azimuth-dependent half-value width of the scattering intensity derived from the 110 plane is larger than the above range, the orientation is not sufficient, and the heat resistance and rigidity are not sufficient. The lower limit of the azimuth-dependent half-value width of the scattering intensity derived from the 110 plane is preferably 5 degrees, more preferably 7 degrees, and further preferably 8 degrees. If the full width at half maximum of the 110 plane is smaller than the above range, the impact resistance may be lowered and the orientation crack may occur.

The full width at half maximum specified in the present invention is preferably measured using X-rays having high parallelism, and synchrotron radiation is preferably used.
The X-ray source used for wide-angle X-ray diffraction measurement may be a general device such as a tube type or a rotary type used in a laboratory, but a high-intensity light source capable of irradiating high-intensity synchrotron radiation with high parallelism. Is preferably used. With synchrotron radiation, X-rays do not spread easily and the brightness is high, so measurement can be performed with high accuracy and in a short time. For example, even a film sample with a thickness of several tens of microns can be measured with a single film without overlapping the films. Moreover, since highly accurate measurement is possible, detailed crystal orientation evaluation becomes possible. On the other hand, with low-brightness X-rays, when measuring a film sample with a thickness of several tens of microns, it takes a long time to measure unless multiple sheets are overlapped, and when multiple sheets are overlapped, a slight deviation occurs. As a result, the peak when the scattering intensity of 110 planes is plotted against the azimuth becomes broad, and the value of the obtained half width tends to increase.
Examples of equipment capable of irradiating high-intensity synchrotron radiation with high parallelism include large-scale synchrotron radiation facilities such as SPring-8, which are owned by the Frontier Soft Matter Development Industry-Academia Union (FSBL), for example. It is preferable to measure the half width of the present invention using the beamline BL03XU.

The polypropylene film used as the base film of the present invention preferably has a large long-period size. In general, crystalline polymers have a regular laminated structure (periodic structure) consisting of repeating crystalline and amorphous structures. Here, the size of the repeating unit composed of crystals and amorphous is called a long-period size. This long-period size can be obtained from the scattering peak angle derived from the long-period structure in the main orientation direction measured by the small-angle X-ray scattering method.

As for the long-period scattering peak by the small-angle X-ray scattering measurement of the polypropylene film used as the base material of the present invention, it is preferable that the peak is clearly observed in the main orientation direction. Here, the main orientation direction indicates a direction in which scattering due to the long period of polymer crystals is more strongly observed in the two-dimensional X-ray scattering pattern. In the case of uniaxial stretching, the main orientation direction often coincides with the stretching direction, and in the case of sequential biaxial stretching of longitudinal stretching-transverse stretching, the main orientation direction in the transverse stretching direction depends on the respective stretching ratios. Often match. The more clearly the long-period peaks caused by polymer crystals are observed, the more ordered the long-period structure is formed.

In the polypropylene film used as the base material of the present invention, the long-period size obtained from the long-period scattering peak is preferably 40 nm or more. The lower limit of the long period size is more preferably 41 nm, still more preferably 43 nm. If the long-period size is smaller than the above range, the melting peak temperature will be low and therefore the heat resistance will be insufficient. The upper limit of the long period size is preferably 100 nm, more preferably 90 nm, and even more preferably 80 nm. If the long-period size is larger than the above range, crystallization or heat treatment takes a long time, which makes practical production difficult.

The X-ray source used for the small-angle X-ray scattering measurement is not particularly limited, and a general device such as a tube type or a rotary type used in a laboratory can be used. However, the wide-angle X-ray diffraction measurement described above can be used. It is preferable to use a high-intensity light source capable of irradiating high-intensity synchrotron radiation, as in the case of the X-ray source used in In particular, since the polypropylene film of the present invention has a large long period, X-ray scattering derived from the long period structure is in the region on the smaller angle side. Therefore, since it is difficult to measure with a laboratory X-ray apparatus having a large X-ray beam diameter and a short camera length, it is difficult for X-rays to spread, the beam diameter can be narrowed down to several hundred microns or less, and the beam diameter can be narrowed down to several hundred microns or less. It is preferable to measure the ultra-small angle region under a long camera length using synchrotron radiation with high brightness. At this time, the camera length is preferably 7 m or more.

Examples of the base film of the present invention include oriented films mainly composed of propylene-based polymers satisfying the following requirements (a) to (c) and satisfying the following requirements (d). (A) The content of comonomer other than propylene is 0.5 mol% or less (b) The mesopentad fraction is 96% or more. (C) The melt flow rate (MFR) is 0.5 g / 10 minutes or more and 20 g / 10 minutes or less. (D) It is preferable that the half width of the maximum peak when the scattering intensity of 110 planes of the α-type crystal of polypropylene measured by the wide-angle X-ray scattering method is plotted against the azimuth is 30 degrees or less.

The polypropylene film used as the base material of the present invention may be a uniaxially stretched film in the longitudinal direction (MD direction) or the lateral direction (TD direction), but is more preferably a biaxially stretched film from the viewpoint of heat resistance. By stretching at least uniaxially, it is possible to obtain a film having a low heat shrinkage rate at a high temperature and a high degree of heat resistance, which was not expected with a conventional polypropylene film. Examples of the stretching method include a simultaneous biaxial stretching method and a sequential biaxial stretching method, but the sequential biaxial stretching method is preferable from the viewpoint of flatness, dimensional stability, uneven thickness and the like.

As a sequential biaxial stretching method, polypropylene resin is heated and melted by a single-screw or twin-screw extruder so that the resin temperature is 200 ° C. or higher and 280 ° C. or lower, and the polypropylene resin is formed into a sheet from a T-die and 10 ° C. or higher and 100 ° C. Extrude onto a chill roll at a temperature below to obtain an unstretched sheet. Then, the roll was stretched 3.0 times or more and 8.0 times at 120 ° C. or higher and 165 ° C. or lower in the longitudinal direction (MD direction), followed by preheating with a tenter, and then 155 ° C. or higher and 175 ° C. in the lateral direction (TD direction). It can be stretched 4.0 times or more and 20.0 times or less at the following temperature. Further, after biaxial stretching, the heat fixing treatment can be performed at a temperature of 165 ° C. or higher and 175 ° C. or lower while allowing relaxation of 1% or higher and 15% or lower.

The base film used in the present invention preferably contains particles in the film to form protrusions on the film surface in order to impart handleability (for example, winding property after lamination). The particles contained in the film include inorganic particles such as silica, kaolinite, talc, calcium carbonate, zeolite, and alumina, and heat-resistant polymer particles such as acrylic, PMMA, nylon, polystyrene, polyester, and benzoguanamine-formalin condensate. Can be mentioned. From the viewpoint of transparency, the content of particles in the film is preferably small, for example, 1 ppm or more and 1000 ppm or less. Further, from the viewpoint of transparency, it is preferable to select particles having a refractive index close to that of the resin to be used. In addition, in order to impart various functions to the base film as needed, antioxidants, UV absorbers, antistatic agents, dyes, lubricants, nucleating agents, adhesives, antifogging agents, flame retardants, anti-fog agents. It may contain a blocking agent, an inorganic or organic filler, and the like.

The base film used in the present invention is used as long as the object of the present invention is not impaired for the purpose of improving the mechanical properties of the base film and the adhesiveness with the ink layer and the adhesive layer laminated on the coating layer. , A resin other than the polypropylene-based polymer that satisfies the above-mentioned requirements (a) to (c) may be contained. Examples thereof include a polypropylene resin different from the polypropylene-based polymer, a random copolymer which is a copolymer of propylene and ethylene and / or an α-olefin having 4 or more carbon atoms, and various elastomers.

The base film used in the present invention may be a single-layer film or a composite film having two or more layers in which a surface layer and a central layer are laminated. In the case of a composite film, there is an advantage that the functions of the surface layer and the central layer can be designed independently. For example, the composite film as a whole is transparent by containing particles only in the thin surface layer to form irregularities on the surface to maintain handleability, while substantially not containing particles in the thick central layer. Can be further improved. The method for producing the composite film is not particularly limited, but in consideration of productivity, the raw materials of the surface layer and the center layer are extruded from separate extruders and guided to one die to obtain an unstretched sheet, so-called co-extrusion. Lamination by the extrusion method is preferable.

In the present invention, the thickness of the base film is arbitrarily set according to each application, but the lower limit is preferably 2 μm or more, more preferably 3 μm or more, still more preferably 4 μm or more. On the other hand, the upper limit of the thickness is preferably 300 μm or less, more preferably 250 μm or less, still more preferably 200 μm or less. When the thickness is thin, the handleability tends to be poor. On the other hand, when the thickness is thick, not only is there a problem in terms of cost, but also when the product is wound into a roll and stored, poor flatness due to winding habits is likely to occur.

The haze of the polypropylene film used as the base material of the present invention is preferably low, specifically 6% or less, more preferably 4.5% or less, still more preferably 4.5% or less, from the viewpoint of visibility of the contents. It is 3.5% or less. The haze has a low molecular weight constituting the polypropylene polymer constituting the base film, for example, when the stretching temperature and the heat fixing temperature are too high, the cooling roll (CR) temperature is high and the cooling rate of the unstretched raw fabric sheet is slow. If there are too many components, it tends to be worse, and by adjusting these, it can be controlled within the above range. The haze in the present invention is a value measured using a turbidity meter (NDH2000, manufactured by Nippon Denshoku Co., Ltd.) in accordance with JIS K7136.

When the polypropylene film used as the base material of the present invention is a biaxially stretched film, the lower limit of Young's modulus (23 ° C.) in the MD direction is preferably 2 GPa, more preferably 2.2 GPa, and further preferably 2. It is .4 GPa. The upper limit of Young's modulus in the MD direction is preferably 4 GPa, more preferably 3.7 GPa, and even more preferably 3.3 GPa. When the Young's modulus in the MD direction is in the above range, it has high rigidity, is easy to manufacture realistically, and improves the MD-TD balance.

When the polypropylene film used as the base material of the present invention is a biaxially stretched film, the lower limit of Young's modulus (23 ° C.) in the TD direction is preferably 3.8 GPa, more preferably 4 GPa, and further preferably 4 .2 GPa. The upper limit of Young's modulus in the TD direction is preferably 8 GPa, more preferably 7 GPa, and even more preferably 6.5 GPa. When the Young's modulus in the TD direction is in the above range, it has high rigidity, is easy to manufacture realistically, and improves the MD-TD balance. The Young's modulus can be increased by increasing the draw ratio, for example, and in the case of MD-TD stretching, the MD draw ratio is set low and the TD draw ratio is set high in the TD direction. Young's modulus can be increased. The Young's modulus in the present invention is a value measured in the MD direction and the TD direction of the film at 23 ° C. according to JIS K 7127.

As a method of laminating the coating layer on the base film, any known method can be used, but a method of applying and drying the coating liquid on the base film is preferable. Known coating methods such as gravure coating method, kiss coating method, dip method, spray coating method, curtain coating method, air knife coating method, blade coating method, reverse roll coating method, bar coating method, and lip coating method are available. Can be mentioned.

As a method for dissolving or dispersing the inorganic layered particles, polyurethane resin and the like contained in the coating liquid in a solvent, a method of stirring and dispersing these using a known disperser is preferable. Specific examples thereof include ball mills, sand mills, attritors, roll mills, agitators, colloid mills, ultrasonic homogenizers, homomixers, pearl mills, wet jet mills, paint shakers, butterfly mixers, planetary mixers, Henschel mixers and the like.

The concentration of the solid content of the inorganic layered particles, the polyurethane resin, etc. contained in the coating liquid is preferably 3% by mass or more and 30% by mass. By adjusting the concentration of the solid content of the coating liquid to 3% by mass or more, it is possible to suppress a decrease in productivity due to a long drying time after coating. On the other hand, by adjusting the concentration of the solid content of the coating liquid to 30% by mass or less, it is possible to prevent deterioration of the leveling property due to an increase in the viscosity of the coating liquid and accompanying deterioration of the coating appearance. Further, from the viewpoint of coating appearance, it is preferable to adjust the solid content concentration of the coating liquid or the blending amount of the type of organic solvent so that the viscosity of the coating liquid is in the range of 5 cps or more and 300 cps or less.

The thickness of the coating layer after coating and drying depends on the degree of gas barrier property required, but is preferably 0.1 μm or more and 5 μm or less, and the lower limit is 0.3 μm or more and the upper limit is 3 μm or less. Is preferable. If the thickness of the coating layer is thinner than 0.1 μm, it is difficult to obtain gas barrier properties and adhesive strength, while if it exceeds 5 μm, the load during coating and drying increases and the manufacturing cost increases, which is not preferable.

Examples of the method of applying the coating liquid on the base film and then drying it include known hot air drying and infrared heaters, but hot air drying having a high drying speed is preferable.

The drying temperature after coating is preferably 60 ° C. or higher and 150 ° C. or lower, and particularly preferably the lower limit is 70 ° C. or higher and the upper limit is 120 ° C. or lower. If the temperature is lower than 60 ° C., the solvent contained in the coating liquid cannot be sufficiently removed, and problems such as brushing may occur. On the contrary, when the temperature exceeds 150 ° C., minute defects of the coating film such as fine coating missing, fine repellent, and cracks derived from bubbles are likely to occur, and the appearance may be deteriorated. Further, the shrinkage of the base film due to heat is strong, and the flatness of the base film may be deteriorated due to heat wrinkles, or the mechanical properties of the base film may be deteriorated.

The tension of the base film applied during drying is preferably 30 N / m or more and 150 N / m or less, and particularly preferably the lower limit is 50 N / m or more and the upper limit is 120 N / m or less. If the tension of the film is less than 30 N / m, the traveling film meanders, and it becomes difficult to apply the coating liquid uniformly. On the contrary, when it exceeds 150 N / m, wrinkles are generated in the base film, the flatness is deteriorated, and the appearance of the wound film is deteriorated. Further, when the heat resistance of the base film is inferior, it is stretched in the traveling direction of the base film and shrinks in the width direction during drying, and in the worst case, the base film is broken and other problems occur in productivity.

In the present invention, other than the antistatic layer, the easy-adhesive layer, the adhesive layer, the easy-slip layer, the resin layer containing a dye such as a dye or a pigment, etc., as long as the effect of the present invention is not impaired on the surface not provided with the coating layer. The function of may be added.

(Laminated body)
A heat-sealing resin layer called a sealant provided in a known laminated film can be laminated on the laminated film of the present invention with or without an adhesive layer to form a laminated body. This laminate is suitable as a packaging material. The heat-sealing resin layer can be provided on any one side or both sides of the laminated film, but it is preferably provided on the coating layer from the viewpoint of protecting the coating layer having gas barrier properties. The thermoplastic polymer that forms the heat-sealable resin layer may be any as long as it can sufficiently exhibit sealant adhesiveness, and is a polyethylene resin such as HDPE, LDPE, LLDPE, a polypropylene resin, or an ethylene-vinyl acetate copolymer. , Ethethylene-α-olefin random copolymer, ionomer resin and the like can be used.

The heat-sealing resin layer is generally formed by an extrusion laminating method, a dry laminating method, or the like. However, in the laminated film of the present invention, an adhesive layer is laminated on a coating layer, and the above resin film or sheet is formed. Is preferably dry-laminated to form a thermosetting resin layer. By forming such a laminated body, it is possible to exhibit the high adhesive strength of the laminated film of the present invention. As the adhesive for forming the adhesive layer, a known dry laminate adhesive can be used.

Further, in the laminated film of the present invention, at least one or more printing layers may be laminated between or outside the coating layer or the base film and the thermosetting resin layer. As the printing ink forming the printing layer, water-based and solvent-based resin-containing printing inks can be preferably used. Examples of the resin used for the printing ink include an acrylic resin, a urethane resin, a polyester resin, a vinyl chloride resin, a vinyl acetate copolymer resin, and a mixture thereof. Known printing inks include antistatic agents, light blocking agents, ultraviolet absorbers, plasticizers, lubricants, fillers, colorants, stabilizers, lubricants, defoamers, cross-linking agents, blocking agents, antioxidants, etc. Additives may be included. The printing method for providing the print layer is not particularly limited, and known printing methods such as an offset printing method, a gravure printing method, and a screen printing method can be used. For drying the solvent after printing, known drying methods such as hot air drying, hot roll drying, and infrared drying can be used.

The laminated film of the present invention as described above can more highly achieve both excellent gas barrier properties and sufficient adhesive strength in a high humidity environment, and is suitably used as a packaging material for foods, pharmaceuticals, industrial products, etc. Can be done.
Further, as a preferred embodiment of the present invention, when a film in which a polypropylene film having high heat resistance and rigidity is used as a base material and a coating layer containing a polyurethane resin having gas barrier properties and inorganic layered particles is laminated is used, it is considered to have gas barrier properties. Both properties of adhesive strength can be more highly compatible, and it can be suitably used for food packaging such as confectionery and bread.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is naturally not limited to the following Examples. The film properties obtained in each example were measured and evaluated by the following methods.

(1) Mesopentad fraction and meso-average chain length The mesopentad fraction and meso-average chain length were measured ^{using 13} C-NMR. The mesopentad fraction is according to the method described in "Zambelli et al., Macromolecules, Vol. 6, p. 925 (1973)", and the meso-average chain length is "Polymer Sequence Division" by J.C. Randall, Chapter 2 ( 1977) (Academic Press, New York) ”. The 13C-NMR measurement was carried out by dissolving 200 mg of a sample in a mixed solution of o-dichlorobenzene and dibenzene in an 8: 2 (volume ratio) at 135 ° C. using “AVANCE500” manufactured by BRUKER, and performing the measurement at 110 ° C.

(2) Xylene-soluble component 1 g of a polypropylene sample is dissolved in 200 ml of boiling xylene, allowed to cool, and then recrystallized in a constant temperature water bath at 20 ° C. for 1 hour. The ratio was defined as the xylene-soluble content (% by mass).

(3) Melt flow rate (MFR)
According to JIS K7210, the measurement was performed at a temperature of 230 ° C. and a load of 2.16 kgf.

(4) Molecular Weight and Molecular Weight Distribution The molecular weight and molecular weight distribution were determined by gel permeation chromatography (GPC) on the basis of monodisperse polystyrene. The measurement conditions of the column, solvent, etc. used in the GPC measurement are as follows.
Solvent: 1,2,4-trichlorobenzene Column: TSKgel GMHHR-H (20) HT x 3
Flow rate: 1.0 ml / min
Detector: RI
Measurement temperature: 140 ° C
The number average molecular weight (Mn) and the mass average molecular weight (Mw) are each defined by the following equations by the number of molecules (Ni) of the molecular weight (Mi) at each elution position of the GPC curve obtained via the molecular weight calibration curve.
Number average molecular weight: Mn = Σ (Ni ・ Mi) / ΣNi
Mass average molecular weight: Mw = Σ (Ni ・ Mi ² ) / Σ (Ni ・ Mi)
Molecular weight distribution: Mw / Mn
Further, the molecular weight at the peak position of the GPC curve was defined as Mp.
When the baseline is not clear, the baseline is set up to the lowest position of the high molecular weight side skirt of the high molecular weight side elution peak closest to the elution peak of the standard substance.

(5) 110 half-price width by wide-angle X-ray diffraction In the base film of the present invention, in the second hatch of the beamline BL03XU owned by the Frontier Soft Matter Development Industry-Academia Union (FSBL) in the large radiation facility SPring-8. The measurement film was set so that the angle between the X-ray source direction and the film surface was perpendicular, and wide-angle X-ray (WAXS) measurement was performed. The measurement conditions are shown below.
The X-ray wavelength is 0.1 nm, and the transmittance is determined from the value of the ion chamber set before and after the sample using an imaging plate (RIGAKU R-AXIS VII) or a CCD camera with an image intensifier (Hamamatsu Photonics V7739P + ORCA R2) as a detector. Was calculated. Air scattering correction was performed on the obtained two-dimensional image in consideration of dark current (dark noise) and transmittance. _{Cerium oxide (CeO 2} ) was used to measure the camera length, and Fit2D (European Synchron Radiation Facility software [http://www.esrf.eu/computing/scientific/FIT2D/]) was used (110). The azimuth profile of was calculated.

(6) Long-period size by small-angle X-ray scattering method In the second hatch of the beamline BL03XU owned by the Frontier Soft Matter Development Industry-Academia Union (FSBL) in the large radiation facility SPring-8, the MD direction of the film is moved up and down. , The measurement film was set so that the TD direction was left and right and the angle between the X-ray source direction and the film surface was vertical, and small-angle X-ray (SAXS) measurement was performed. The measurement conditions are shown below.
The X-ray wavelength is 0.2 nm, the camera length is about 7.7 m, and an imaging plate (RIGAKU R-AXIS VII) is used as the detector, and the scattering vector q is in the range of 0.01 to 0.5 (nm-1). Scattered image was obtained. Here, the scattering vector q is calculated by the equation q = 4πsin θ / λ, where θ is half the scattering angle 2θ, π is the pi, and λ is the wavelength of the X-ray. The obtained scattered image was corrected for air scattering in consideration of dark current (dark noise) and transmittance in the same manner as the WAXS measurement, and collagen separately calibrated with silver behenate was used for accurate camera length measurement. .. Using the Fit2d software described above, the profile of the sample in the width direction was calculated, and the horizontal axis was the scattering vector q (nm- ¹ ) and the vertical axis was the common logarithm of the intensity I (q). Here, the calculation range of the profile is ± 5 degrees from the width direction.

(7) Young's modulus The Young's modulus of the film in the MD direction and the TD direction was measured at 23 ° C. according to JIS K 7127.

(8) The measurement was performed using a turbidity meter (NDH2000, manufactured by Nippon Denshoku Co., Ltd.) in accordance with Haze JIS K7136.

(9) Average Particle Size of Inorganic Layered Particles Dilute with ion-exchanged water so that the content of the inorganic layered particles in the dispersion containing the inorganic layered particles is 0.05% by mass, and use a laser diffraction type particle size distribution meter. The particle size distribution was measured using (SALD-7500 manufactured by Shimadzu Corporation). The average value of the particle size distribution was calculated and used as the average particle size.

(10) Heat shrinkage rate Measured by the following method in accordance with JIS Z 1712. A base material obtained by removing the laminated film (B) obtained in Examples and Comparative Examples and the coating layer laminated on the laminated film with a solution containing tetrahydrofuran and ion-exchanged water in a ratio of 1: 1 (mass ratio). Each of the films (A) was cut into a size of 20 mm in width and 200 mm in length in the MD direction and the TD direction, respectively, and hung in a hot air oven at 120 ° C. and heated for 5 minutes. The length after heating was measured, and the ratio (percentage) of the contracted length to the original length was defined as the heat shrinkage rate.

(11) Oxygen permeability Measured under the conditions of 20 ° C. and 80% RH using an oxygen permeability measuring device (“OX-TRAN 2/20” manufactured by MOCON) according to JIS K7126-2A. Here, those having an oxygen permeability of 150 ml / m ² · day · MPa or less are considered to have an oxygen barrier property, and those having an oxygen permeability of 100 ml / m ² · day · MPa or less are those having an excellent oxygen barrier property and 50 ml / m ² -Day · MPa or less was judged to have a particularly excellent oxygen barrier property.

(12) Water vapor permeability Measurement was carried out under the conditions of 40 ° C. and 90% RH using a water vapor permeability measuring device (PERMATRAN-W3 / 33 manufactured by MOCON) according to JIS K7129-B. Here, those having a water vapor permeability of 5.0 g / m ² · day or less are considered to have a water vapor barrier property, and those having a water ^{vapor permeability of 4.5 g / m 2} · day or less are those having an excellent water vapor barrier property and 4.0 g /. It ^{was judged that m 2} · day or less had a particularly excellent water vapor barrier property.

(13) Laminate strength Adhesives for laminating (“TM329” and “CAT-8B” manufactured by Toyobo Co., Ltd. “TM329” and “CAT-8B” manufactured by Toyo Morton Co., Ltd. are applied 1: 1 on the coating layer surface side of the laminated films obtained in Examples and Comparative Examples by dry lamination processing. A 30 μm-thick unstretched polypropylene film (“P1128” manufactured by Toyobo Co., Ltd.) is laminated so as to be in contact with the corona-treated surface, and aged at 40 ° C. for 4 days. As a result, a laminate for evaluation was obtained. The thickness of the adhesive layer formed of the urethane-based two-component curable adhesive after drying was about 3 μm.
The laminate obtained above was cut into a test piece having a width of 15 mm and a length of 200 mm, and under the conditions of a temperature of 23 ° C. and a relative humidity of 65%, a Tensilon universal material tester (Tensilon UMT-II manufactured by Toyo Baldwin Co., Ltd.) Lamination strength was measured using "-500 type"). In the measurement of the laminate strength, the tensile speed was set to 200 mm / min, and the laminate strength was measured by peeling off by 90 °. Here, it was determined that a laminate strength of 2.0 N / 15 mm width or more had excellent adhesive strength, and a laminate strength of 2.5 N / 15 mm width or more had particularly excellent adhesive strength.

(14) Presence or absence of wrinkles When a coating layer is provided by applying and drying to a base film having a width of 300 mm and a length of 1000 m, if wrinkles do not occur in the obtained laminated film, it is good (○). Was judged to be defective (x).

(15) Appearance of coating When a coating layer is provided by coating and drying on a base film having a width of 300 mm and a length of 1000 m, if no brushing, coating loss, or repelling is observed on the coating layer, it is good (○), defective. If was found, it was judged to be defective (x).

(16) Shrinkage in the Width Direction Before and After Coating A base film having a width of 300 mm and a length of 1000 m was coated and dried to provide a coating layer, and then the film width and length were measured. When the film width length before coating was a and the film width length after coating was b, the shrinkage ratio in the film width direction (shrinkage ratio in the width direction) before and after coating was determined by the following formula. If this shrinkage rate is 2.0% or less, it is judged to be good, and if it exceeds 2.0%, it is judged to be poor.
Width direction shrinkage rate (%) = (ab) × 100 / a

(Manufacturing of base film S-1)
As a polypropylene resin, a propylene homopolymer having Mw / Mn = 7.7, MFR = 5.0 g / 10 minutes, and mesopentad fraction = 97.3% ("Novatec (registered trademark) PP SA4L" manufactured by Japan Polypropylene Corporation: Co. The amount of the polymerized monomer was 0 mol%; hereinafter abbreviated as "PP-1").
This polypropylene resin is extruded into a sheet from a T-die at 250 ° C. using a 60 mm extruder, cooled and solidified with a cooling roll at 30 ° C., and then 4.5 times in the length direction (MD direction) at 135 ° C. Vertically stretched, then clipped on both ends, guided into a hot air oven, preheated at 170 ° C, stretched 8.2 times laterally (TD direction) at 160 ° C, then relaxed by 6.7%. The heat treatment was carried out at 168 ° C. Then, both ends were trimmed with a shear blade, one side of the film was corona-treated, and the film was wound with a winder to obtain a base film having a thickness of 20 μm. The polypropylene structure of the obtained base film is shown in Table 1, the film forming conditions are shown in Table 2, and the physical properties of the base film are shown in Table 3, respectively.

(Manufacturing of base film S-2)
As a polypropylene resin, a propylene homopolymer having Mw / Mn = 8.9, MFR = 3.0 g / 10 minutes, and mesopentad fraction = 97.1% (Samsuntal "HU300": copolymerization monomer amount is 0 mol). %; Hereinafter abbreviated as "PP-2"), except that the preheating temperature for transverse stretching was 171 ° C, the transverse stretching temperature was 161 ° C, and the heat treatment temperature after transverse stretching was 170 ° C. A substrate film having a thickness of 20 μm was obtained in the same manner as in -1). The polypropylene structure of the obtained base film is shown in Table 1, the film forming conditions are shown in Table 2, and the physical properties of the base film are shown in Table 3, respectively.

(Manufacturing of base film S-3)
Low molecular weight propylene with a molecular weight of 10,000 with respect to 90 parts by mass of the propylene homopolymer (PP-1) used in the base film (S-1) (Mitsui Chemicals High Wax "NP105": Copolymerization monomer amount is 0 mol %) To a total of 100 parts by mass by adding 10 parts by mass, melt-kneading with a 30 mm twin-screw extruder, Mw / Mn = 11, MFR = 7.0 g / 10 minutes, mesopentad fraction = 96.5%. Pellets of a mixture of propylene polymers (hereinafter abbreviated as “PP-3”) were obtained. A base film having a thickness of 20 μm was obtained in the same manner as the base film (A-1) except that the pellets were used as a polypropylene resin. The polypropylene structure of the obtained base film is shown in Table 1, the film forming conditions are shown in Table 2, and the physical properties of the base film are shown in Table 3, respectively.

(Manufacturing of base film S-4)
A base film having a thickness of 20 μm was obtained in the same manner as the base film (S-3) except that the base film was stretched 5.5 times in the length direction and 12 times in the lateral direction. The polypropylene structure of the obtained base film is shown in Table 1, the film forming conditions are shown in Table 2, and the physical properties of the base film are shown in Table 3, respectively.

(Manufacturing of base film S-5)
As a polypropylene resin, a propylene homopolymer having Mw / Mn = 4.0, MFR = 6.0 g / 10 minutes, and mesopentad fraction = 98.7% (copolymerization monomer amount is 0 mol%; hereinafter, “PP-4”. A base film having a thickness of 20 μm was obtained in the same manner as the base film (S-1) except that (abbreviated as) was used. The polypropylene structure of the obtained base film is shown in Table 1, the film forming conditions are shown in Table 2, and the physical properties of the base film are shown in Table 3, respectively.

(Manufacturing of base film S-6)
As a polypropylene resin, a propylene-ethylene copolymer having Mw / Mn = 4, MFR = 2.5 g / 10 minutes, and mesopentad fraction = 97% (Sumitomo Chemical's "Sumitomo Noblen (registered trademark) FS2011DG3": copolymerized monomer The amount is 0.6 mol%; hereinafter abbreviated as "PP-5"), the longitudinal stretching temperature is 125 ° C., the preheating temperature in transverse stretching is 168 ° C., the transverse stretching temperature is 155 ° C., and the heat treatment temperature after transverse stretching. A base film having a thickness of 20 μm was obtained in the same manner as the base film (S-1) except that the temperature was 163 ° C. The polypropylene structure of the obtained base film is shown in Table 1, the film forming conditions are shown in Table 2, and the physical properties of the base film are shown in Table 3, respectively.

(Manufacturing of base film S-7)
As a polypropylene resin, a propylene homopolymer having Mw / Mn = 4.3, MFR = 0.5 g / 10 minutes, and mesopentad fraction = 97% (copolymerization monomer amount is 0 mol%; hereinafter referred to as “PP-6”. A base film having a thickness of 20 μm was obtained in the same manner as the base film (S-7) except that (omitted) was used. The polypropylene structure of the obtained base film is shown in Table 1, the film forming conditions are shown in Table 2, and the physical properties of the base film are shown in Table 3, respectively.

(Manufacturing of base film S-8)
As a polypropylene resin, a polypropylene polymer having Mw / Mn = 2.8, MFR = 30 g / 10 minutes, and mesopentad fraction = 97.9% (Nippon Polypro's "Novatec (registered trademark) PP SA03": co- An attempt was made to obtain a stretched polypropylene film in the same manner as the base film (S-1) except that the amount of the polymerized monomer was 0 mol%; hereinafter abbreviated as “PP-7”). The film broke during stretching and could not be biaxially stretched.

(Polymerization of water-dispersed polyurethane resin U)
In a four-necked flask equipped with a stirrer, a Dimroth condenser, a nitrogen introduction tube, a silica gel drying tube, and a thermometer, 45.59 parts by mass of metaxylylene diisocyanate, 1,3-bis (isocyanate methyl) cyclohexane) 93. 90 parts by mass, 24.8 parts by mass of ethylene glycol, 13.40 parts by mass of dimethylol propionic acid, and 80.20 parts by mass of methyl ethyl ketone as a solvent are mixed and stirred at 70 ° C. for 5 hours under a nitrogen atmosphere to prepare a reaction solution. It was confirmed that the predetermined amine equivalent was reached. Next, the reaction solution was cooled to 40 ° C., and then 9.60 parts by mass of triethylamine was added to obtain a polyurethane prepolymer solution. Next, 624.80 parts by mass of water was added to a reaction vessel equipped with a homodisper capable of high-speed stirring, the temperature was adjusted to 25 ° C., and the polyurethane prepolymer solution was added while stirring and mixing at 2000 min-1. The mixture was dispersed in water, and 21.10 parts by mass of 2-[(2-aminoethyl) amino] ethanol was added to carry out a chain extension reaction. Then, by removing methyl ethyl ketone and a part of water under reduced pressure, an aqueous dispersion type polyurethane resin (U) having a solid content of 30% by weight and an average particle size of 90 nm was obtained.

(Preparation of Inorganic Layered Particle Dispersion Liquid C-1)
Water-swellable mica (Somasif ME-100, manufactured by Corp Chemical Co., Ltd.), which is an inorganic layered particle, and ion-exchanged water are placed in a container of a bead mill (SUPERAPEXMILL manufactured by Kotobuki Engineering & Research Co., Ltd., beads: 0.1 mm, rotation speed: 5000 rpm). The dispersion treatment was carried out at a ratio of 11 (mass ratio) at room temperature for 30 minutes, and then foreign substances and agglomerates were removed using a filter having a nominal filtration accuracy of 50 μm to obtain an inorganic layered particle dispersion. The solid concentration of the obtained inorganic layered particle dispersion was 8.1%, and the average particle size was 2.0 μm.

(Preparation of Inorganic Layered Particle Dispersion Liquid C-2)
An inorganic layered particle dispersion was obtained in the same manner as the inorganic layered particle dispersion (C-1) except that the dispersion treatment time was 20 minutes. The solid concentration of the obtained inorganic layered particle dispersion was 8.0%, and the average particle size was 3.0 μm.

(Preparation of Inorganic Layered Particle Dispersion Liquid C-3)
An inorganic layered particle dispersion was obtained in the same manner as the inorganic layered particle dispersion (C-1) except that the dispersion treatment time was 10 minutes. The solid concentration of the obtained inorganic layered particle dispersion was 8.1%, and the average particle size was 4.1 μm.

(Preparation of Inorganic Layered Particle Dispersion Liquid C-4)
An inorganic layered particle dispersion was obtained in the same manner as the inorganic layered particle dispersion (C-1) except that the dispersion treatment time was 1 minute. The solid concentration of the obtained inorganic layered particle dispersion was 7.6%, and the average particle size was 6.5 μm.

(Preparation of Inorganic Layered Particle Dispersion Liquid C-5)
An inorganic layered particle dispersion was obtained in the same manner as the inorganic layered particle dispersion (C-1) except that water-swellable montmorillonite (Kunipia F, manufactured by Kunimine Kogyo Co., Ltd.) was used as the inorganic layered particles. The solid concentration of the obtained inorganic layered particle dispersion was 7.8%, and the average particle size was 1.1 μm.

(Example 1)
A film roll having a width of 300 mm and a length of 20 m is applied to the base film (S-1) by roll-to-roll, and the following coating liquid (D-1) is applied by the microgravure method. The thickness of the coating layer after drying. Is applied to 1.0 μm, dried with hot air at a temperature of 80 ° C. for 20 seconds under the condition of a film tension of 80 N / m, and a laminated film is wound around a polypropylene cylindrical core having a diameter of 6 inches and laminated. I got a film.
(Coating liquid D-1)
The following materials were mixed at the mass ratios shown below and stirred for 30 minutes or longer to dissolve. Then, the undissolved matter was removed using a filter having a nominal filtration accuracy of 50 μm to prepare a coating liquid (D-1).
-Ion-exchanged water 47.50% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 30.00% by mass
-Inorganic layered particle dispersion (C-2) 12.50% by mass

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 2)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the base film was changed to the base film (S-2).

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 3)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the base film was changed to the base film (S-3).

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 4)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the base film was changed to the base film (S-4).

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 5)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the base film was changed to the base film (S-5).

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 6)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-2).
(Coating liquid D-2)
-Ion-exchanged water 47.65% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 30.00% by mass
-Inorganic layered particle dispersion (C-1) 12.35% by mass

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 7)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-3).
(Coating liquid D-3)
-Ion-exchanged water 47.65% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 30.00% by mass
-Inorganic layered particle dispersion (C-3) 12.35% by mass

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 8)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-4).
(Coating liquid D-4)
-Ion-exchanged water 46.84% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 30.00% by mass
-Inorganic layered particle dispersion (C-4) 13.16% by mass

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 9)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-5).
(Coating liquid D-5)
・ Ion-exchanged water 53.00% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 32.00% by mass
-Inorganic layered particle dispersion (C-2) 5.00% by mass

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 10)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-6).
(Coating liquid D-6)
・ Ion-exchanged water 38.33% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 26.67% by mass
-Inorganic layered particle dispersion (C-2) 25.00% by mass

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 11)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-7).
(Coating liquid D-7)
・ Ion-exchanged water 53.45% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 32.17% by mass
-Inorganic layered particle dispersion (C-2) 4.38% by mass

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 12)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-8).
(Coating liquid D-8)
・ Ion-exchanged water 33.75% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 25.00% by mass
-Inorganic layered particle dispersion (C-2) 31.25% by mass

The obtained laminated film had good gas barrier properties and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 13)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-9).
(Coating liquid D-9)
・ Ion-exchanged water 43.33% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 30.00% by mass
・ Water-swellable mica particle dispersion 16.67% by mass
(NTS-5 manufactured by Topy Industries, average particle size 8.6 μm, solid content ratio 6.0%)

The obtained laminated film had good gas barrier properties and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 14)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-10).
(Coating liquid D-10)
-Ion-exchanged water 47.18% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 30.00% by mass
-Inorganic layered particle dispersion (C-5) 12.82% by mass

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Example 15)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the base film was changed to the base film (S-7).

The obtained laminated film had good gas barrier properties and transparency, and also had good adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Comparative Example 1)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the base film was changed to a biaxially stretched polyester film (Toyobo ester film: E5100, thickness 12 μm).

The obtained laminated film had good transparency, but had poor oxygen barrier properties and water vapor barrier properties, and had poor gas barrier properties. The adhesive strength as a laminated body was good. The results obtained are shown in Table 4.

(Comparative Example 2)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the base film was changed to the base film (S-6).

The obtained laminated film had good gas barrier properties and transparency, but had poor adhesive strength as a laminated body. The results obtained are shown in Table 4.

(Comparative Example 3)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-11).
(Coating liquid D-11)
・ Ion-exchanged water 56.67% by mass
・ Isopropanol 10.00% by mass
-Water-dispersed polyurethane resin (U) 33.33% by mass

The obtained laminated film had good transparency, but had poor oxygen barrier properties and poor gas barrier properties. The adhesive strength as a laminated body was good. The results obtained are shown in Table 4.

(Comparative Example 4)
In Example 1, a laminated film was obtained in the same manner as in Example 1 except that the coating liquid forming the coating layer was changed to the following coating liquid (D-12).
(Coating liquid D-12)
・ Ion-exchanged water 17.50% by mass
・ Isopropanol 10.00% by mass
・ Polyvinyl alcohol aqueous solution 60.00% by mass
(OKS8149 manufactured by Nippon Synthetic Chemistry, solid content ratio 10%)
-Inorganic layered particle dispersion (C-2) 12.50% by mass

The obtained laminated film had good transparency, but had poor oxygen barrier properties and poor gas barrier properties. The adhesive strength as a laminated body was also poor. The results obtained are shown in Table 4.

(Example 16)
A film roll having a width of 300 mm and a length of 1000 m is applied to the base film (S-1) by roll-to-roll, and the coating liquid (D-1) is applied by a microgravure method. The thickness of the coating layer after drying is 1 μm. Under the condition of film tension of 80 N / m, the film was dried with hot air at a temperature of 80 ° C. for 20 seconds, and a laminated film was wrapped around a polypropylene cylindrical core with a diameter of 6 inches to a width of 300 mm and a length of 300 mm. A 1000 m laminated film roll was prepared.

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. In addition, the obtained laminated film had the same gas barrier properties and transparency as in Example 1, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 17)
In Example 16, a laminated film roll was prepared in the same manner except that the base film was changed to the base film (S-2).

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. Further, the obtained laminated film had the same gas barrier property and transparency as in Example 2, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 18)
In Example 16, a laminated film roll was prepared in the same manner except that the base film was changed to the base film (S-3).

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. Further, the obtained laminated film had the same gas barrier property and transparency as in Example 3, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 19)
In Example 16, a laminated film roll was prepared in the same manner except that the base film was changed to the base film (S-4).

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. Further, the obtained laminated film had the same gas barrier property and transparency as in Example 4, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 20)
In Example 16, a laminated film roll was prepared in the same manner except that the base film was changed to the base film (S-5).

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. Further, the obtained laminated film had the same gas barrier property and transparency as in Example 5, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 21)
In Example 16, a laminated film roll was prepared in the same manner except that the base film was changed to the base film (S-7).

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. Further, the obtained laminated film had the same gas barrier property and transparency as in Example 15, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 22)
In Example 16, a laminated film roll was prepared in the same manner except that the drying temperature was changed to 60 ° C.

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. In addition, the obtained laminated film had the same gas barrier properties and transparency as in Example 1, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 23)
In Example 16, a laminated film roll was prepared in the same manner except that the drying temperature was changed to 150 ° C.

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. In addition, the obtained laminated film had the same gas barrier properties and transparency as in Example 1, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 24)
In Example 16, a laminated film roll was prepared in the same manner except that the film tension was changed to 30 N / m.

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. In addition, the obtained laminated film had the same gas barrier properties and transparency as in Example 1, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Example 25)
In Example 16, a laminated film roll was prepared in the same manner except that the film tension was changed to 150 N / m.

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The coated appearance of the obtained laminated film was good, and the shrinkage ratio in the width direction was also good. In addition, the obtained laminated film had the same gas barrier properties and transparency as in Example 1, and the adhesive strength was good as a laminated body. The results obtained are shown in Table 5.

(Comparative Example 5)
In Example 16, a laminated film roll was prepared in the same manner except that the base film was changed to the base film (S-6).

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander, but wrinkles were generated and the productivity was unsuitable. The coated appearance of the obtained laminated film was good, but the shrinkage in the width direction was poor. The results obtained are shown in Table 5.

(Comparative Example 6)
In Example 16, a laminated film roll was prepared in the same manner except that the drying temperature was changed to 50 ° C.

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander or wrinkle, and the film could be produced without any problem in productivity. The shrinkage ratio in the width direction of the obtained laminated film was good, but the appearance of the coating was poor due to repellency. The results obtained are shown in Table 5.

(Comparative Example 7)
In Example 16, a laminated film roll was prepared in the same manner except that the drying temperature was changed to 160 ° C.

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander, but wrinkles were generated and the productivity was unsuitable. The coating appearance of the obtained laminated film was also poor due to coating loss, and the shrinkage in the width direction was poor. The results obtained are shown in Table 5.

(Comparative Example 8)
In Example 16, a laminated film roll was prepared in the same manner except that the film tension was changed to 20 N / m.

When the coating liquid for forming the coating layer was applied to the base film and dried, no wrinkles were generated, but the running film meandered and the productivity was unsuitable. Due to the meandering of the traveling film, it was not possible to produce a laminated film.

(Comparative Example 9)
In Example 16, a laminated film roll was prepared in the same manner except that the film tension was changed to 160 N / m.

When the coating liquid for forming the coating layer was applied and dried on the base film, the running film did not meander, but wrinkles were generated and the productivity was unsuitable. The coated appearance of the obtained laminated film was good, but the shrinkage in the width direction was poor. The results obtained are shown in Table 5.

Since the laminated film of the present invention has both excellent gas barrier properties in a high humidity environment and sufficient adhesive strength of the coating layer to the base film, protection of the contents, expiration date and extension of product life are required. It is suitable as a packaging material for foods, pharmaceuticals, and industrial products. Further, in terms of manufacturing, the high heat resistance and rigidity of the base film and the small deterioration in quality of the coating layer with respect to the usage environment make the printing layer and the laminating layer a drying process at the time of laminating, and a bag when used as a packaging material. It can contribute to the improvement of productivity and quality stability during the heating process during body processing, and has a great contribution to the industrial world.

Claims (10)

A laminated film having a coating layer on at least one surface of the base film, the base film is an orientation film mainly composed of a propylene-based polymer, and the coating layer has a diisocyanate component of xylylene diisocyanate and hydrogenated xyl. A water-dispersible polyurethane resin composed of at least one selected from range isocyanate and inorganic layered particles are contained, and the heat shrinkage rate A of the base film and the heat shrinkage rate B of the laminated film at 120 ° C. of the laminated film are contained. difference (a-B) is the MD direction, TD direction, both 0.3% or more state, and are 3.0% or less, and the MD direction of the heat shrinkage at 120 ° C. of the laminated film is more than 0.4% A laminated film having a heat shrinkage rate of 0.6% or more in the TD direction. The laminated film according to claim 1, wherein the base film is an orientation film mainly composed of a propylene-based polymer that satisfies the following requirements (a) to (c), and also satisfies the following requirement (d).
(A) Mesopentad fraction of 96% or more (b) Content of comonomer other than propylene is 0.5 mol% or less (c) Melt flow rate (MFR) is 0.5 g / 10 minutes or more, 20 g / 10 minutes or less ( d) The half-value width of the maximum peak when the scattering intensity of 110 planes of polypropylene α-type crystal measured by the wide-angle X-ray scattering method is plotted against the azimuth is 30 degrees or less. The laminated film according to claim 1 or 2, wherein the long-period size obtained from the long-period scattering peak in the main orientation direction measured by the small-angle X-ray scattering method of the base film is 40 nm or more. The invention according to any one of claims 1 to 3, wherein the average particle size of the inorganic layered particles is 2.0 μm or more and 6.5 μm or less, and the content of the inorganic layered particles is 4% by mass or more and 20% by mass or less. Laminated film. The laminated film according to any one of claims 1 to 4, wherein the heat shrinkage ratios of the laminated film in the MD direction and the TD direction at 120 ° C. are both 1.0% or less. The laminated film according to any one of claims 1 to 5, wherein the haze of the laminated film is 5.0% or less. The method for producing a laminated film according to claims 1 to 6, wherein the diisocyanate component is a water-dispersible polyurethane resin composed of at least one selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate, and inorganic layered particles. A step of applying a coating liquid containing at least a solvent to a propylene-based polymer-oriented film to form a coating layer, and then adjusting the tension of the propylene-based polymer-oriented film to 30 N / m or more and 150 N / m or less, and a propylene-based polymer. A method for producing a laminated film, which comprises a step of volatilizing a solvent contained in a coating layer to form a coating layer while maintaining the temperature of the alignment film in the range of 60 ° C. or higher and 150 ° C. or lower. A laminate in which an adhesive layer and a thermosetting resin layer are sequentially laminated on the coating layer of the laminated film according to any one of claims 1 to 6. A laminated film roll comprising the laminated film according to any one of claims 1 to 6. The method for producing a laminated film roll according to claim 9, wherein the diisocyanate component is a water-dispersible polyurethane resin composed of at least one selected from xylylene diisocyanate and hydrogenated xylylene diisocyanate, inorganic layered particles, and a solvent. A step of applying a coating solution containing at least the above to a propylene-based polymer-oriented film to form a coating layer, and then adjusting the tension of the propylene-based polymer-oriented film to 30 N / m or more and 150 N / m or less, and propylene-based polymer orientation. A step of forming a coating layer by volatilizing the solvent contained in the coating layer while maintaining the film temperature in the range of 60 ° C. or higher and 150 ° C. or lower, and a step of winding up the laminated film on which the coating layer is formed. A method for producing a laminated film roll.