KR101865070B1 - Coated film - Google Patents

Abstract

A coating film which can be suitably used as a substrate for a magnetic recording medium, various packaging materials, various building materials, various displays, and the like can be suitably used in view of its excellent adhesion with various functional layers do. A coating film having a coating layer formed from a coating liquid containing a (meth) acryloyl group-containing resin and a urethane resin-containing composite resin on at least one side of a film.

Description

[Coated film]

The present invention relates to a coating film, and more particularly to a coating film excellent in adhesion to a functional layer laminated on a coating film.

Although the film is widely used as having excellent properties, there is a drawback that the adhesion is bad depending on the use. For example, it is possible to use a printing ink (a printing ink for cellophane, a chlorinated PP ink, a UV curing ink, a magnetic ink and the like), a thermal transfer ink, a magnetic paint, an adhesive (a lamination adhesive, · Inorganic materials (aluminum, silver, gold, ITO, silicon oxide, aluminum oxide, etc.), release agents, ink receiving layer, gelatin, polyvinyl alcohol, polyvinyl acetal, cellulose acetoacetate, , Methylcellulose, carboxymethylcellulose, and the like.

As a method for improving the adhesiveness of a film, there are a method of treating the film with a solvent, a corona discharge treatment, a plasma treatment or the like (Patent Literatures 1 and 2), but these methods have various functional layers The effect of improving the adhesiveness of the coating layer is insufficient and a method of laminating a coating layer having adhesiveness on the film by the coating treatment has been proposed. However, even when the adhesion property is insufficient in the kind of the functional layer provided on the coating layer (Patent Document 3).

Patent Document 1: JP-A-3-56541 Patent Document 2: JP-A-11-129378 Patent Document 3: JP-A-2004-001486

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coating film excellent in adhesiveness to a functional layer laminated on a coating film.

DISCLOSURE OF THE INVENTION The present inventors have intensively studied in view of the above-mentioned circumstances, and as a result, they found that the above-described problems can be easily solved by using a coating film containing a specific constitution, and the present invention has been accomplished.

That is, the gist of the present invention is to provide a coating film comprising a coating layer formed from a coating liquid containing a resin containing a (meth) acryloyl group on at least one side of a film and a composite resin containing a urethane resin do.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a coating film excellent in adhesiveness to various functional layers such as an ink layer containing, for example, an active energy ray-curable compound or the like, and its industrial value is high.

Carrying out the invention  Form for

As the film substrate of the coated film of the present invention, conventionally known ones can be used, and examples thereof include polyester films, polycarbonate films, fluororesin films, polyimide films, triacetyl cellulose films, polyolefin films, polyacrylate films, polystyrene Film, a polyvinyl chloride film, a polyvinyl alcohol film, an ethylene-vinyl acetate copolymer film, an ethylene-vinyl alcohol copolymer film, and a nylon film. Particularly, in order to develop it for various purposes, it is preferable that it has heat resistance, and a polyester film, a polycarbonate film, a fluororesin film and a polyimide film are suitably used, and in consideration of transparency, moldability, Is more suitably used.

The film constituting the coating film of the present invention may have a single layer structure, a multi-layer structure, a multi-layer structure, or a multi-layer structure of four or more layers, without departing from the gist of the present invention.

As the polyester film, the polyester to be used may be homopolyester or copolymerized polyester. When the homopolyester is included, it is preferable that the homopolyester is obtained by polycondensing an aromatic dicarboxylic acid and an aliphatic glycol. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid. Examples of the aliphatic glycol include ethylene glycol, diethylene glycol, 1,4-cyclohexanedimethanol and the like. Representative polyesters include polyethylene terephthalate and the like. On the other hand, examples of the dicarboxylic acid component of the copolyester include one or two kinds of isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid, sebacic acid, oxycarboxylic acid (e.g., p- And examples of the glycol component include one or more of ethylene glycol, diethylene glycol, propylene glycol, butanediol, 4-cyclohexanedimethanol, neopentyl glycol, and the like.

The polymerization catalyst of the polyester is not particularly limited and conventionally known compounds can be used. Examples thereof include antimony compounds, titanium compounds, germanium compounds, manganese compounds, aluminum compounds, magnesium compounds and calcium compounds. Among them, the titanium compound and the germanium compound are preferable because the catalytic activity is high, the polymerization can be carried out in a small amount, and the amount of the metal remaining in the film is small. Further, from the point that the germanium compound is expensive, it is more preferable to use a titanium compound.

In the case of a polyester using a titanium compound, the titanium element content is preferably 50 ppm or less, more preferably 1 to 20 ppm, and still more preferably 2 to 10 ppm. When the content of the titanium compound is too large, deterioration of the polyester is accelerated in the step of melt-extruding the polyester, resulting in a film having a strong yellowish color. When the content of the titanium compound is too small, Or a film having sufficient strength may not be obtained. In the case of using a polyester with a titanium compound, it is preferable to use a phosphorus compound in order to lower the activity of the titanium compound for the purpose of suppressing deterioration in the melt extrusion step. As the phosphorus compound, polyphosphoric acid is preferable in view of polyester productivity and thermal stability. The content of the phosphorus element is preferably 1 to 300 ppm, more preferably 3 to 200 ppm, and still more preferably 5 to 100 ppm with respect to the amount of polyester to be melt-extruded. If the content of the phosphorus compound is too large, it may cause gelation or foreign matter. If the content is too small, the activity of the titanium compound can not be sufficiently lowered, resulting in a yellowish film .

As the polycarbonate film, conventionally known polycarbonate may be used, but a type containing a bisphenol A structure is particularly preferable.

As the fluororesin film, conventionally known fluororesins may be used, and examples thereof include polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether Copolymers and the like.

In order to improve the weatherability of the film and deterioration of the liquid crystal and the like, an ultraviolet absorber may be contained in the film. The ultraviolet absorber is not particularly limited as long as it is a compound that absorbs ultraviolet light and can withstand the heat added in the production process of the film.

As the ultraviolet absorber, there are an organic ultraviolet absorber and an inorganic ultraviolet absorber, but from the viewpoint of transparency, an organic ultraviolet absorber is preferable. Examples of the organic ultraviolet absorber include, but are not limited to, cyclic imino ester, benzotriazole, and benzophenone. From the viewpoint of durability, the cyclic imino ester type and benzotriazole type are more preferable. It is also possible to use two or more ultraviolet absorbers in combination.

It is also possible to incorporate particles in the film for the main purpose of imparting releasability and preventing damage in each step. The type of the particles to be incorporated is not particularly limited as long as the particles can impart lubricity, and specific examples thereof include silica, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, Titanium and the like, organic particles such as acrylic resin, styrene resin, urea resin, phenol resin, epoxy resin and benzoguanamine resin. In the film production process, precipitation particles in which a part of metal compounds such as catalysts are precipitated and finely dispersed can be used.

The shape of particles to be used is not particularly limited, and any of spherical, massive, rod-shaped, and flat-shaped shapes may be used. The hardness, specific gravity, color, and the like are not particularly limited. These series of particles may be used in combination of two or more as necessary.

The average particle diameter of the particles is preferably 5 占 퐉 or less, more preferably 0.01 to 3 占 퐉. By using the average particle diameter in the above range, problems are not likely to be caused even when the film is provided with appropriate surface roughness and various functional layers are formed in a later step.

The content of the particles in the film is preferably less than 5% by weight, more preferably 0.0003 to 3% by weight. In the case of no or small particles, the transparency of the film becomes high, which results in a good film. However, since the slidability becomes insufficient in some cases, researches for improving slidability by incorporating particles in the coating layer Sometimes it is necessary. When the content of the particles is too large, the haze is not sufficiently lowered even if the functional layer is formed, and the transparency of the film may be insufficient.

The method of adding particles to the film is not particularly limited, and conventionally known methods can be employed. For example, it may be added at any stage of producing the film constituting each layer, but it is preferably added after the esterification or transesterification reaction is completed.

In addition to the above-mentioned particles, conventionally known antioxidants, antistatic agents, heat stabilizers, lubricants, dyes, pigments and the like may be added to the film in the film.

The thickness of the film is not particularly limited as long as the film can be formed into a film, but is usually in the range of 10 to 350 mu m, more preferably in the range of 20 to 300 mu m.

The production examples of the films will be described in detail, but the production examples are not limited to these examples. Generally, the resin is melted, formed into a sheet, and subjected to stretching for the purpose of increasing the strength, etc., and a film is formed. As an example, the case of producing the polyester film described above will be introduced. A method in which a pellet obtained by drying a polyester raw material is cooled and solidified in a cooling roll by a molten film extruded from a die using an extruder to obtain an unstretched film. In this case, in order to improve the planarity of the film, it is preferable to improve the adhesion between the film and the rotary cooling drum, and the electrostatic adhesion method or the liquid application adhesion method is preferably employed. The resulting unstretched film is then stretched in the biaxial direction. In this case, first, the unstretched film is stretched in one direction by a roll or tenter stretching machine. The stretching temperature is usually 70 to 120 占 폚, preferably 80 to 110 占 폚, and the stretching magnification is usually 2.5 to 7 times, preferably 3.0 to 6 times. Next, the stretching is performed in a direction perpendicular to the stretching direction of the first stage. In this case, the stretching temperature is usually 70 to 170 占 폚, and the stretching ratio is usually 3.0 to 7 times, preferably 3.5 to 6 times. Thus, heat treatment is subsequently carried out at a temperature of 180 to 250 ° C under relaxation or within 30% to obtain a biaxially oriented film. In the above stretching, a method of stretching in one direction in two or more stages can be employed. In this case, it is preferable that the stretching magnifications in the two directions finally fall within the above ranges.

For the production of the film, simultaneous biaxial stretching may be employed. The simultaneous biaxial stretching method is a method in which the above unstretched sheet is simultaneously stretched in the machine direction and the width direction under the temperature-controlled state at 70 to 120 캜, preferably 80 to 110 캜, But it is preferably 4 to 50 times, preferably 7 to 35 times, and more preferably 10 to 25 times in magnification. Subsequently, heat treatment is carried out at a temperature of 170 to 250 ° C under relaxation or under a relaxation of 30% or less to obtain a stretched orientation film. Conventionally known stretching methods such as a screw method, a pantograph method, and a linear driving method can be employed for the simultaneous axial stretching device employing the above-described stretching method.

Next, the formation of the coating layer will be described. The coating layer may be provided by in-line coating in which the film surface is processed during the film-forming process of the film, or off-line coating may be applied outside the system on the film once formed. More preferably, it is formed by in-line coating.

The in-line coating is a method of coating in a film production process. Specifically, the in-line coating is a method in which the resin is melt-extruded, and then the coating is performed at any stage from stretching to thermoforming and winding. Usually, it is coated on any of an unstretched sheet obtained by melting and quenching, a stretched uniaxially stretched film, a biaxially stretched film before heat setting, and a film before winding after heat fixing. For example, in the case of sequential biaxial stretching, a method of stretching in the transverse direction after coating on a uniaxially stretched film stretched in the longitudinal direction (longitudinal direction) is excellent. According to this method, since the film formation and the coating layer formation can be performed at the same time, there is merit in production cost, and since the drawing is performed after coating, the thickness of the coating layer can be changed by the stretching magnification, The thin film coating can be performed more easily. Further, by providing a coating layer on a film before stretching, the coating layer can be stretched together with the base film, whereby the coating layer can be tightly adhered to the base film. Further, in the production of a biaxially oriented film, stretching while supporting the film ends by a clip or the like enables the film to be restrained in the longitudinal direction and in the transverse direction. In the heat fixation, . Therefore, since the heat treatment performed after the application can be made at a high temperature that can not be attained by other methods, the film formability of the application layer can be improved, the application layer and the base film can be adhered more firmly, A strong coating layer can be formed, and the performance such as adhesiveness with various functional layers which can be formed on the coating layer, resistance to moist heat and the like can be improved.

In the present invention, it is essential that at least one side of the film has a coating layer formed from a coating liquid containing a (meth) acryloyl group-containing resin and a urethane resin-containing composite resin.

The coating layer in the present invention is formed from an active energy ray-curable coating of a general solventless form, such as various functional layers, in particular, a curable resin layer by an active energy ray, and in particular, an active energy ray curable ink layer , It is most suitable for improving the adhesiveness with the curable resin layer which is generally difficult to ensure the adhesiveness.

The inventors of the present invention have found that high adhesiveness can be exhibited by using a resin containing a (meth) acryloyl group and a composite resin containing a urethane resin. The mechanism of high degree of adhesion development is based on the assumption that the carbon-carbon double bond due to the (meth) acryloyl group present in the coating layer and the carbon-carbon double bond in the compound used for forming To form a covalent bond. (Meth) acryloyl group as well as a urethane resin, it is possible to achieve not only an improvement in the adhesiveness with the functional layer but also an improvement in the adhesiveness with the base film, As a result, it is estimated that the adhesiveness is improved.

The resin containing a (meth) acryloyl group is not particularly limited as long as it is a resin containing a (meth) acryloyl group, and examples thereof include conventionally known resins such as an epoxy resin, a polyester resin and an acrylic resin. Among them, an epoxy resin is preferable from the viewpoint of easy synthesis and from the viewpoint that many (meth) acryloyl groups can be introduced. Of the epoxy resins, aromatic-containing epoxy resins are preferable from the viewpoint of excellent durability such as water resistance and solvent resistance, and among them, novolak-type epoxy resins and bisphenol-type epoxy resins are more preferable, and (meth) From the viewpoint of introduction, a novolak type epoxy resin is also preferable.

Examples of the novolak type epoxy resin include cresol novolak type and phenol novolak type. Examples of the bisphenol type epoxy resin include bisphenol A type, bisphenol F type and bisphenol S type. Among them, a cresol novolak type epoxy resin and a bisphenol A type epoxy resin are more preferable in consideration of versatility and flexibility of the resin. The epoxy resin may be used singly or in combination.

The urethane resin for forming a composite resin with a resin containing a (meth) acryloyl group may be a conventionally known urethane resin. Generally, urethane resin is prepared by reaction of polyol and isocyanate. Examples of the polyol include polyester polyols, polycarbonate polyols, polyether polyols, polyolefin polyols, and acrylic polyols. These compounds may be used alone or in combination of two or more. In consideration of the adhesion to the polyester film substrate, polyester polyol is more preferable among the above. In consideration of water resistance, polycarbonate polyols are more preferable among the above.

Examples of the polyester polyols include polyhydric alcohols (such as terephthalic acid, isophthalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, fumaric acid and maleic acid) Ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, 1,3-butanediol, 1,4-butanediol, Propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2- Propanediol, 1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2,5- Hexanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, Diol, cyclohexanediol, bishydroxymethylcyclohexane, dimethanol benzene, 'S hydroxyl include those that can be obtained from ethoxy benzene, alkyl Diallo kanol amine, reaction of the lactone diol, and so on).

Of these, from the viewpoints of durability such as water resistance and solvent resistance, the polyvalent carboxylic acid is preferably an aromatic carboxylic acid, and among these, terephthalic acid and isophthalic acid are more preferable in view of the outer appearance of coating and adhesion to a film substrate. In addition, in consideration of applicability to the outer appearance of the coating and the in-line coat, it is preferable that the flexibility is somewhat good, and it is optimal to use terephthalic acid and isophthalic acid in combination.

The molar ratio of terephthalic acid: isophthalic acid used in combination is preferably 1 to 10: 1 to 10, more preferably 1: 5: 1 to 5, and still more preferably 1: 3: 1 to 3, Preferably in the range of 1 to 2: 1 to 2.

The polyhydric alcohol preferably has a short molecular chain such as ethylene glycol, diethylene glycol or propylene glycol in order to increase the aromatic ratio of the carboxylic acid component, and it is preferable that diethylene glycol is contained in consideration of the flexibility of the resin . Considering the durability, the appearance of application, and the flexibility, it is more preferable to use ethylene glycol and diethylene glycol in combination. The molar ratio of ethylene glycol: diethylene glycol used in combination is preferably 1 to 10: 1 to 10, more preferably 1: 5: 1 to 5, and still more preferably 1: 3: 1 to 3 , And particularly preferably in the range of 1 to 2: 1 to 2.

The polycarbonate polyols can be obtained from a polyhydric alcohol and a carbonate compound by a dealcohol reaction. Examples of the polyhydric alcohols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, Hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10- Pentyl glycol, 3-methyl-1,5-pentanediol, and 3,3-dimethylolheptane. Examples of the carbonate compound include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate and the like. Examples of the polycarbonate-based polyols obtainable from these reactions include poly (1,6-hexylene) carbonate, poly Methyl-1,5-pentylene) carbonate, and the like.

Examples of the polyether polyols include polyethylene glycol, polypropylene glycol, polyethylene propylene glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol and the like.

Examples of the polyisocyanate compound used for obtaining the urethane resin include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate, naphthalene diisocyanate and tolylidine diisocyanate, α, α, α aliphatic diisocyanates having aromatic rings such as? ',?' - tetramethylxsilylene diisocyanate, aliphatic diisocyanates such as methylene diisocyanate, propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate and hexamethylene diisocyanate, Alicyclic diisocyanates such as hexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and isopropylidene dicyclohexyl diisocyanate. Diisocyanate, and the like. These may be used alone or in combination of two or more. Among them, it is preferable that the aromatic isocyanate is not an aromatic isocyanate in consideration of the sulfur modification.

A chain extending agent may be used when synthesizing a urethane resin. The chain extending agent is not particularly limited as long as it has two or more active groups reactive with an isocyanate group. Generally, a chain extending agent having two hydroxyl groups or amino groups Can be mainly used.

Examples of the chain extender having two hydroxyl groups include aliphatic glycols such as ethylene glycol, propylene glycol and butanediol, aromatic glycols such as xylylene glycol and bishydroxyethoxybenzene, esters such as neopentyl glycol hydroxy pivalate Glycols such as glycols. Examples of the chain extender having two amino groups include aromatic diamines such as tolylene diamine, xylylenediamine and diphenylmethanediamine, ethylenediamine, ethylenediamine, propylenediamine, hexanediamine, 2,2-dimethyl- Butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,6-hexanediamine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexylmethanediamine, isopropylidenecyclohexyl-4,4'-diamine, 1,4 - alicyclic diamines such as diaminocyclohexane, 1,3-bisaminomethylcyclohexane, and the like.

The urethane resin may be a solvent, preferably water, as the medium. In order to disperse or dissolve the urethane resin in water, there are a forced emulsification type using an emulsifying agent, a self emulsification type in which a hydrophilic group is introduced into a urethane resin, or a receiving type. In particular, the self-emulsification type in which an ionic group is introduced into the urethane resin structure by ionization is preferable because of excellent storage stability of the solution, water resistance of the obtained coating layer, transparency and adhesiveness.

As the ionic group to be introduced, various groups such as a carboxyl group, a sulfonic acid, a phosphoric acid, a phosphonic acid, and a quaternary ammonium salt can be mentioned, but a carboxyl group is preferable. As a method for introducing a carboxyl group into the urethane resin, various methods can be mentioned in each step of the polymerization reaction. For example, there is a method in which a resin having a carboxyl group is used as a copolymerization component in the synthesis of a prepolymer, and a method in which a component having a carboxyl group is used as a component such as a polyol, a polyisocyanate or a chain extender. Particularly, it is preferable to use a carboxyl group-containing diol to introduce a desired amount of a carboxyl group in accordance with the amount of the component.

For example, dimethylolpropionic acid, dimethylolbutanoic acid, bis- (2-hydroxyethyl) propionic acid, bis- (2-hydroxyethyl) butanoic acid and the like can be copolymerized with the diol used for the polymerization of the urethane resin. The carboxyl group is preferably in the form of a salt neutralized with ammonia, an amine, an alkali metal, an inorganic alkali, or the like. Particularly preferred are ammonia, trimethylamine, and triethylamine. Such a polyurethane resin can be used as a crosslinking reaction point of a crosslinking agent by a carboxyl group from which a neutralizing agent has been removed in a drying step after coating. As a result, it is possible to further improve the durability, solvent resistance, water resistance, blocking resistance, and the like of the resulting coating layer, as well as being excellent in stability in the liquid state before coating.

The composite resin of the (meth) acryloyl group-containing resin and the urethane resin can be produced, for example, by mixing and stirring a resin containing a (meth) acryloyl group and a urethane resin in a solvent such as water . More specifically, for example, in the case of a type in which a urethane resin contains a hydrophilic group, a resin containing a (meth) acryloyl group in a state of dispersing or dissolving a urethane resin in an aqueous medium or a resin dispersed or dissolved in a solvent (Meth) acryloyl group is mixed and stirred. It is preferable that the resin containing the (meth) acryloyl group has no hydrophilic group or becomes hydrophobic when it is small, and is mixed with the dispersion medium of the urethane resin or the medium for dispersion in the state of being dispersed or dissolved by using an organic solvent In this case, however, by removing the organic solvent in which the (meth) acryloyl group-containing resin is dispersed or dissolved by, for example, decompression, a resin containing a minor amount of a (meth) A composite resin emulsion having a core shell structure in which a hydrophilic urethane resin is a shell can be obtained. It is more preferable to use a core shell structure because it can stabilize the liquid and stably exist even when mixed with other components and can be widely used. According to the above-described method, since the core and the shell are not combined, when the emulsion is destroyed by solvent removal after drying after the application, the core and the shell can freely move independently of each other, The (meth) acryloyl group can come out to the surface of the coating layer, which can be advantageous for improving the adhesion with various functional layers that can be formed on the coating layer.

The proportion of the (meth) acryloyl group in the composite resin is usually in the range of 1 to 50 wt%, preferably 3 to 30 wt%, more preferably 5 to 25 wt%, and still more preferably 8 to 20 wt% . The use in the above range can improve the adhesion to various functional layers formed on the coating layer.

The weight ratio of the resin containing a (meth) acryloyl group to the urethane resin is usually in the range of 1 to 5: 1 to 5, preferably 1: 3: 1 to 3, and more preferably 1: 2: 1 to 2 . When used in the above-described range, the adhesiveness to various functional layers formed on the coating layer and the adhesion to the polyester film as the substrate can be improved. Also, in the case of forming a core shell structure as the composite resin, the use in the above range is also preferable in the synthesis.

In order to form a coating layer, various polymers may be used in combination to improve the appearance of the applied coating, transparency, adhesiveness, and the like.

Specific examples of the polymer include urethane resin, polyester resin, acrylic resin, polyvinyl (polyvinyl alcohol, polyvinyl chloride, vinyl chloride vinyl acetate copolymer and the like), polyalkylene glycol, polyalkyleneimine, methylcellulose, hydroxy Cellulose, pre-sorting, and the like.

In order to form a coating layer, it is preferable to use a crosslinking agent in combination with the active energy ray-curable ink layer or the like in order to strengthen the coating layer of the coating layer and to improve the sufficient adhesion and anti-wet heat characteristics.

Specific examples of the crosslinking agent include an oxazoline compound, an epoxy compound, a carbodimide compound, an isocyanate compound, a melamine compound, a silane coupling compound, a hydrazide compound, and an aziridine compound. Among them, an oxazoline compound, an epoxy compound, a carbodimide compound and an isocyanate compound are preferable from the viewpoint of improving the adhesiveness.

The oxazoline compound is a compound having an oxazoline group in the molecule, particularly a polymer containing an oxazoline group, and may be prepared by polymerization with an addition polymerizable oxazoline group-containing monomer alone or with other monomers. The addition polymerizable oxazoline group-containing monomer is at least one member selected from the group consisting of 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline and the like. Can be used. Of these, 2-isopropenyl-2-oxazoline is industrially easily available and is suitable.

The other monomer is not particularly limited as long as it is a monomer copolymerizable with the addition polymerizable oxazoline group-containing monomer, and examples thereof include alkyl (meth) acrylates (examples of the alkyl group include a methyl group, ethyl group, n-propyl group, isopropyl group, Butyl group, t-butyl group, 2-ethylhexyl group, and cyclohexyl group); Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, styrenesulfonic acid and its salts (sodium salt, potassium salt, ammonium salt and tertiary amine salt); Unsaturated nitriles such as acrylonitrile and methacrylonitrile; (Meth) acrylamide, N-alkyl (meth) acrylamide and N, N-dialkyl (meth) acrylamide. Examples of the alkyl group include a methyl group, ethyl group, n-propyl group, Butyl group, t-butyl group, 2-ethylhexyl group, cyclohexyl group, etc.); Vinyl esters such as vinyl acetate and vinyl propionate; Vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; ? -Olefins such as ethylene and propylene; Halogen-substituted?,? - unsaturated monomers such as vinyl chloride, vinylidene chloride and vinyl fluoride; And?,? - unsaturated aromatic monomers such as styrene,? -Methylstyrene, and the like, and these monomers may be used alone or in combination.

The content of the oxazoline group contained in the oxazoline compound is usually 0.5 to 10 mmol / g, preferably 1 to 9 mmol / g, more preferably 3 to 8 mmol / g, Is in the range of 4 to 6 mmol / g. Use in the above range is preferable because adhesion to various functional layers is improved.

The epoxy compound is a compound having an epoxy group in the molecule and includes, for example, a condensation product of epichlorohydrin with a hydroxyl group or an amino group such as ethylene glycol, polyethylene glycol, glycerin, polyglycerin and bisphenol A, Diepoxy compounds, monoepoxy compounds, glycidylamine compounds, and the like. Examples of the polyepoxy compound include sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, triglycidyl tris (2-hydroxyethyl) Examples of the isocyanate, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether and diepoxy compound include neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, resorcin diglycidyl ether, Polyglycoldiglycidyl ether, polytetramethylene glycol diglycidyl ether, monoepoxy compound, polyglycidyl ether, polyglycerol diglycidyl ether, polyglycerol diglycidyl ether, Include, for example, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, glycidyl amine Examples of water include N, N, N ', N'-tetraglycidyl-m-xylylenediamine, and 1,3-bis (N, N-diglycidylamino) cyclohexane.

The carbodiimide compound is a compound having a carbodiimide structure and is a compound having at least one carbodiimide structure in the molecule, but for better adhesion and the like, a polycarbodiimide having two or more carbodiimide Based compounds are more preferable.

The carbodiimide compound can be synthesized by a conventionally known technique, and a condensation reaction of a diisocyanate compound is generally used. The diisocyanate compound is not particularly limited and any of aromatic and aliphatic diisocyanate compounds may be used. Specific examples thereof include tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, phenylene diisocyanate, naphthalene diisocyanate Isocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, dicyclohexyl diisocyanate, dicyclohexylmethane diisocyanate, and the like.

In order to improve water solubility and water dispersibility of the polycarbodiimide compound within the range not to lose the effect of the present invention, addition of a surfactant and addition of a polyalkylene oxide, a quaternary ammonium salt of a dialkylamino alcohol, A hydroxyalkylsulfonic acid salt or the like may be added to the composition.

The isocyanate compound is a compound having an isocyanate derivative structure represented by isocyanate or block isocyanate. Examples of the isocyanate include aromatic isocyanates such as tolylene diisocyanate, xylylene diisocyanate, methylene diphenyl diisocyanate, phenylene diisocyanate and naphthalene diisocyanate, and aromatic isocyanates such as α, α, α'-tetramethylxylylene Aliphatic isocyanates having an aromatic ring such as diisocyanate and the like, aliphatic isocyanates such as methylene diisocyanate, propylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate and hexamethylene diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, iso And alicyclic isocyanates such as methylenebis (4-cyclohexylisocyanate), isopropylidene dicyclohexyl diisocyanate, and the like.

Also included are polymers and derivatives of these isocyanates such as buretide, isocyanurate, uretdionate and carbodiimide-modified products. These may be used alone or in combination of two or more. Among the isocyanates, aliphatic isocyanates or alicyclic isocyanates are more preferable than aromatic isocyanates in order to avoid yellowing due to ultraviolet rays.

When used in the form of a block isocyanate, examples of the block agent include a phenol compound such as a bisulfate, phenol, cresol, and ethylphenol, an alcohol compound such as propylene glycol monomethyl ether, ethylene glycol, benzyl alcohol, methanol, Compounds, active methylene compounds such as dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate and acetylacetone, mercaptan compounds such as butyl mercaptan and dodecyl mercaptan, ε-caprolactam, δ-valerolactam , An amine compound such as diphenyl aniline, aniline or ethyleneimine, an acid amide compound such as acetanilide or acetic acid amide, formaldehyde, acetal aldehyde, acetone oxime, methyl ethyl ketone oxime, cyclohexanone oxime or the like Oxime-based compounds. These may be used alone or in combination of two or more.

The isocyanate compound may be used alone or in combination with various polymers or in combination. In order to improve the dispersibility and the crosslinking property of the isocyanate compound, it is preferable to use a mixture of a polyester resin and a urethane resin or a combination thereof.

The melamine compound is a compound having a melamine skeleton in the compound, for example, a compound obtained by partially or completely etherifying an alkylated melamine derivative, an alkylated melamine derivative by an alcohol, and a mixture thereof. As the alcohol used in the etherification, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, isobutanol and the like are suitably used. As the melamine compound, any of a monomer and a dimer or more of a dimer or the like may be used, or a mixture thereof may be used. In addition, a co-condensation of urea or the like with a part of melamine may be used, or a catalyst may be used to increase the reactivity of the melamine compound.

Further, these crosslinking agents are used in a design to improve the performance of the coating layer by reacting during the drying process or the film forming process. In the finished coating layer, it can be presumed that unreacted products of these crosslinking agents, compounds after the reaction, or a mixture thereof exist.

In order to improve slipperiness and blocking, it is preferable to use particles in combination to form the coating layer. From the viewpoint of transparency of the film, the average particle diameter of the particles is preferably 0.001 to 1.0 mu m, more preferably 0.005 to 0.5 mu m, and more preferably 0.01 to 0.2 mu m.

Examples of the particles to be used include inorganic particles such as silica, alumina and metal oxide, and organic particles such as crosslinked polymer particles. Particularly, from the viewpoints of dispersibility into the coating layer and transparency of the obtained coating film, silica particles are very suitable.

In order to form the coating layer, the antifoaming agent, the coating property improving agent, the thickening agent, the organic lubricant antistatic agent, the ultraviolet absorber, the antioxidant, the foaming agent, the dye and the pigment may be used good.

The composite resin containing a (meth) acryloyl group and the urethane resin as a ratio to the total volatile components in the coating liquid forming the coating layer is generally at least 5% by weight, preferably at least 35% by weight, More preferably in the range of 45 to 99% by weight. If it is outside the above range, the adhesive property may not be sufficient depending on the functional layer provided on the coating layer.

In the coated film of the present invention, it is also possible to provide a coating layer on the surface opposite to the surface on which the above-mentioned coating layer is provided. The opposite surface can be a coating layer depending on the application, and conventionally known ones can be used as constituent components thereof. Examples thereof include crosslinking agents such as polymers such as urethane resins, polyester resins and acrylic resins, oxazoline compounds, epoxy compounds, carbodiimide compounds, isocyanate compounds and melamine compounds, and these materials can be used alone Or a combination of plural species may be used. The coating layer (the same coating layer on both sides of the film) formed from the coating liquid containing the above-mentioned (meth) acryloyl group-containing resin and the urethane resin-containing composite resin may be used.

Analysis of components in the coating layer can be performed by, for example, analysis of TPF-SIMS, ESCA, fluorescent X-ray or the like.

In the case of providing a coating layer by in-line coating, the above-described series of compounds may be applied as an aqueous solution or an aqueous dispersion and coated with a coating liquid adjusted on the basis of a solid concentration of about 0.1 to 50 wt% It is preferable to produce a film. A small amount of an organic solvent may be contained in the coating liquid for the purpose of improving the dispersibility into water, improving the film formability and the like within the range not impairing the present invention. The organic solvent may be used alone or in combination of two or more.

The film thickness of the coating layer is preferably 0.002 to 1.0 占 퐉, more preferably 0.005 to 0.5 占 퐉, still more preferably 0.005 to 0.3 占 퐉, and particularly preferably 0.01 to 0.2 占 퐉. If the film thickness deviates from the above range, the adhesiveness, coated appearance, and blocking properties may deteriorate.

As a method of providing the application layer, conventionally known coating methods such as reverse gravure coat, direct gravure coat, roll coat, die coat, bar coat, curtain coat and the like can be used.

The drying and curing conditions for forming the coating layer on the film are not particularly limited. For example, when a coating layer is provided by off-line coating, the coating layer is usually cured at 80 to 200 DEG C for 3 to 40 seconds, Is preferably subjected to heat treatment at a temperature of 100 to 180 DEG C for 3 to 40 seconds.

On the other hand, when the coating layer is provided by in-line coating, it is usually preferable to perform heat treatment at 70 to 280 DEG C for 3 to 200 seconds.

In addition, regardless of the off-line coating or the in-line coating, an active energy ray irradiation such as heat treatment and ultraviolet ray irradiation may be used in combination as occasion demands. The film may be subjected to surface treatment such as corona treatment or plasma treatment in advance.

The application layer of the coating film of the present invention is generally used for providing various functional layers. Among the functional layers, an active energy ray curable resin layer and a solventless formulation (solvent content Usually 5% by weight or less, preferably 3% by weight or less, more preferably 1% by weight or less, particularly preferably no solvent), and is characterized in that an ink layer can be provided , The coating film of the present invention is suitable in such fields.

The other components in the functional layer are not particularly limited. Examples thereof include inorganic or organic fine particles, polymerization initiators, polymerization inhibitors, antioxidants, antistatic agents, dispersants, surfactants, light stabilizers and leveling agents. When the film is formed by wet coating and then dried, an arbitrary amount of a solvent may be added.

Example

Hereinafter, the present invention will be described in further detail with reference to Examples, but the present invention is not limited to the following Examples unless it departs from the gist thereof. The measuring method and evaluation method used in the present invention are as follows.

(1) Method of measuring intrinsic viscosity of polyester:

1 g of a polyester obtained by removing the pigment and another polymer component which is incompatible with the polyester was determined and dissolved in 100 ml of a mixed solvent of phenol / tetrachloroethane = 50/50 (weight ratio) and measured at 30 캜.

(2) Method of measuring average particle diameter:

The coating layer was observed using a TEM (H-7650, manufactured by Hitachi High Technologies, Inc., accelerating voltage 100V), and the average value of the particle diameters of 10 particles was taken as the average particle diameter.

(3) Content of (meth) acryloyl group in the composite resin:

The composite resin was dried under reduced pressure, and the respective peaks of 1H and 13C were assigned by NMR (AVANCEIII600, manufactured by Bruker Biospin Co.), and they were calculated.

(4) Method of measuring film thickness of coating layer:

RuO4 the surface of the coating layer ₄ , And embedded in the epoxy resin. Thereafter, the slice prepared by the ultra-thin strip method was dyed with RuO ₄ , and the cross section of the applied layer was measured using TEM (H-7650, manufactured by Hitachi High Technologies, Inc., acceleration voltage: 100 V) Respectively.

(5) Evaluation method of adhesive property:

The surface of the film was printed with an FDT Carlton ACE navy blue (offset printing ink manufactured by Toyo Ink Co., Ltd.) as an active energy ray curable ink, and with an RI tester as an offset printing apparatus, and a metal halide lamp output of 120 W / cm , A line speed of 15 m / min, and an effect condition of a lamp and a film interval of 150 mm. A 10 x 10 cross-cut was made on the ink layer of the obtained film, and a tape 18 mm in width (Cellotape (registered trademark) CT-18 manufactured by Nichiban Co., Ltd.) was adhered thereon and abraded with a peeling angle of 180 degrees. A, 5% or more and less than 20% B, 20% or more and less than 50% C, and 50% or more were evaluated as D (adhesive property 1). In the same manner, the adhesion of an active energy ray-curable ink, FD Carlton ACE Black (offset printing ink manufactured by Toyo Ink Co., Ltd.) was evaluated (Adhesiveness 2). The evaluation criteria are the same.

The polyester used in Examples and Comparative Examples was prepared as follows.

≪ Production method of polyester (A)

100 parts by weight of dimethyl terephthalate, 60 parts by weight of ethylene glycol, 30 parts by weight of ethyl acid phosphate per 100 parts by weight of the produced polyester, and 100 parts by weight of magnesium acetate tetrahydrate as a catalyst and 100 parts by weight of the polyester were subjected to an esterification reaction at 260 占 폚 in a nitrogen atmosphere. Next, tetrabutyl titanate was added in an amount of 50 ppm relative to the produced polyester, and the temperature was raised to 280 DEG C over 2 hours and 30 minutes. The pressure was reduced to an absolute pressure of 0.3 kPa and melt polycondensation was carried out for 80 minutes to obtain an intrinsic viscosity of 0.63 Of polyester (A).

≪ Production method of polyester (B)

100 parts by weight of dimethyl terephthalate, 60 parts by weight of ethylene glycol, and 900 ppm of magnesium acetate tetrahydrate as a catalyst were subjected to an esterification reaction at 225 占 폚 in a nitrogen atmosphere. Subsequently, 3500 ppm of pure phosphoric acid was added to the produced polyester and 70 ppm of germanium dioxide was added to the resulting polyester, and the temperature was raised to 280 DEG C over 2 hours and 30 minutes. The pressure was reduced to 0.4 kPa , And melt-polycondensed to obtain a polyester (B) having an intrinsic viscosity of 0.64.

≪ Production method of polyester (C)

In the production process of the polyester (A), polyester (C) was obtained in the same manner as in the production of polyester (A) except that 0.3 part by weight of silica particles having an average particle diameter of 2 탆 was added before the melt polymerization.

Examples of the compound constituting the coating layer are as follows.

(Example of compound)

A composite resin comprising an acryloyl group-containing resin and a urethane resin: (I)

(Acryloyl group: cresol novolak type epoxy resin monomer = 1: 1.1 (mol%)) and isophorone diisocyanate: terephthalic acid: isophthalic acid: ethylene glycol: diethylene glycol : A polyester-based urethane resin formed from dimethylol propane acid = 12: 19: 18: 21: 25: 5 (mol%) was mixed and dispersed at a solid weight ratio of 1.0: (A resin containing a urethane resin in a shell, urethane resin in a shell). The weight ratio of the acryloyl group to the composite resin was 14% by weight (solid content ratio).

● Urethane resin: (II)

A water dispersion of a polyester-based urethane resin formed from isophorone diisocyanate: terephthalic acid: isophthalic acid: ethylene glycol: diethylene glycol: dimethylolpropanoic acid = 12: 19: 18: 21: 25: 5 (mol%).

• Oxazoline compounds: (IIIA)

An acryl polymer epoxhose having an oxazoline group and a polyalkylene oxide chain (amount of oxazoline group = 4.5 mmol / g, manufactured by Nippon Shokubai Co., Ltd.)

Epoxy compounds: (IIIB)

Polyglycerol polyglycidyl ether.

Particles: (IV)

Silica sol having an average particle diameter of 0.07 mu m

Example  One:

(A) and (B) were used as the raw materials for the outermost layer (surface layer), and the polyester (A) and the polyester (B) were mixed in a ratio of 89%, 5% The mixed raw materials, which were mixed at a ratio of 95% and 5%, respectively, were fed to two extruders as raw materials for the intermediate layer, melted at 285 ° C and then cooled on a cooling roll set at 40 ° C. (Surface layer / intermediate layer / surface layer = 1: 38: 1 flow rate), cooling and solidifying to obtain an unoriented sheet. Subsequently, the film was stretched 3.4 times in the longitudinal direction at a film temperature of 85 占 폚 using a roll speed gauge. The coating liquid 1 shown in Table 1 was applied to both sides of the longitudinally stretched film, ° C and stretched by 2% in the transverse direction to obtain a polyester film having a thickness of 250 탆 and a coating layer having a thickness of the coating layer (after drying) of 0.02 탆. Evaluation of the obtained coating film showed good adhesion to the active energy ray-curable ink layer. The properties of the coated film are shown in Table 2 below.

Example  2 to 10:

A coating film was prepared in the same manner as in Example 1, except that the coating composition of Example 1 was changed to the coating composition shown in Table 1. The coating film thus obtained was as shown in Table 2 and had an adhesive property.

Comparative Example  One:

In Example 1, a coating film was obtained in the same manner as in Example 1 except that no coating layer was provided. Evaluation of the obtained coated film showed that the adhesion of the film was bad, as shown in Table 2.

Comparative Example  2 to 5:

A coating film was prepared in the same manner as in Example 1, except that the coating composition of Example 1 was changed to the coating composition shown in Table 1. The obtained coating film was evaluated, and as shown in Table 2, the adhesion was poor.

Industrial availability

The coated film of the present invention can be suitably used for applications requiring good adhesion with various functional layers such as magnetic recording media, packaging materials, building materials, and displays, for example.

Claims (8)

A coating film having a coating layer on at least one surface of a film and having a functional layer formed on the surface of the coating layer using an active energy ray curable coating material, wherein the coating layer comprises a carbon- (Meth) acryloyl group having a reactive group, and a composite resin containing a urethane resin, and the carbon contained in the compound forming the carbon-carbon double bond functional group in the coating layer - a carbon double bond and reactivity. The coating film according to claim 1, wherein the ratio of the (meth) acryloyl group in the composite resin is 1 to 50% by weight, the weight ratio of the resin containing a (meth) acryloyl group to the urethane resin is 1: 5: . The coating film according to claim 1 or 2, wherein the composite resin is a water-dispersed composite resin having a core-shell structure made of a resin containing an acryloyl group in the core and a urethane resin in the shell. The application film according to claim 1 or 2, wherein the film is a polyester film. delete delete A step of forming a coating layer from a coating liquid containing a (meth) acryloyl group-containing resin and a urethane resin-containing composite resin on at least one side of the film, a compound having a carbon- A process for forming a functional layer by reacting a resin containing a (meth) acryloyl group and a compound having a carbon-carbon double bond in the coating layer after applying an active energy ray- Wherein the functional layer has a thickness of at least 100 nm. delete