JPH01156337A - Polyester film having coating layer - Google Patents

Abstract

PURPOSE:To enable the formation of a polyester film having further improved slipperiness and excellent adhesiveness, antistatic properties and strength of coatings by providing a specified coating layer consisting of a polyurethane or an acrylic resin on the surface of the polyester film. CONSTITUTION:The title polyester film is formed by coating at least one surface of a polyester film with a coating fluid consisting of a polyurethane having both an alkylsulfonate and/or alkylsulfate group and an anionic group and/or an acrylic resin and containing fine particles and drawing the coated film. The anionic group of the polyurethane is used as a lithium, sodium, potassium, magnesium, or ammonium salt of -SO3H, -OSO3H, -COOH, etc. As the acrylic resin, those which are water-soluble or water-dispersible and the main component of which is alkyl (meth)acrylate are pref. As the fine particle, an inorg. particle, an org. particle or a composite particle of org. and inorg. particles can be used.

Description

[Detailed Description of the Invention] [Industrial Field of Application] It is a polyester film with improved coating properties such as M adhesion, corrosion resistance, transparency, and coating strength, and is useful as a base material in various building applications. It is something.

[Conventional technology]

Biaxially stretched polyester film is transparent.

Dimensional stability 2 Mechanical properties, heat resistance, electrical properties.

Photosensitive materials that have excellent gas barrier properties and chemical resistance, and use packaging materials, electrical insulation materials, metal vapor deposition materials, silver salts, diazo compounds, photosensitive resins, etc.

Used as a base material for electrophotographic materials, magnetic recording materials, etc. Recently, as magnetic recording media have become more dense and capacitors have become more capacitive, polyester films have become increasingly flat and clear. Good lubricating properties, ie, smoothness, are required. Improved smoothness,
Films with good transparency are required for plate making, electrophotography, labels, window stickers, vapor-deposited decorative films, and the like. Even the back-treated layers of magnetic recording paper, thermal transfer paper, etc. are required to have high coating strength and slip properties. Furthermore, in these applications, a film that is not easily charged is required as well as the above-mentioned W property.

Conventional methods for improving the slipperiness of polyester films include adding fine organic or inorganic particles to the film (additional particle method), and precipitating transesterification catalyst residue during polyester polymerization. (Precipitated particle method).

Methods based on the composition of the polyester film, such as methods using polymer blends and methods that incorporate organic lubricants, are included. However, the methods using these compositions are
The reality is that if one of the characteristics of flatness and flatness improves, the other will decrease, making it difficult to improve both at the same time. Furthermore, methods based on composition may have limitations in academic applications that require transparency. A method of achieving smoothness by laminating polyester with improved composition with a flat layer by coextrusion etc. is also proposed, but due to the problems caused by the composition mentioned earlier, it is difficult to create a flat layer of polyester with improved composition. problems such as shape transfer. Although there is a method of forming protrusions on the surface by stretching a film that has been surface-treated by solvent treatment, corona discharge treatment, etc., there are various restrictions on the shape of the protrusions, and the slipperiness is often insufficient. In contrast to these methods, a method of forming fine and dense protrusions on the coating layer is attracting attention as a method for smoothing the film. As a method for forming protrusions in the coating layer, the method of incorporating microscopic inorganic particles is widely used to completely improve slipperiness and solid N property (blocking note).
A new method of stretching a polyester film after c (hereinafter referred to as coating and stretching method) using a compound characterized by phase separation in the coating layer and elongation properties during coating and stretching is a new method for producing smooth films. It is attracting attention as a method of delivery. For example, in JP-A-54-43017, gelatin is blended with polyester as a coating agent, and a polyester film with good lubricity is obtained by coating and stretching. Since then, Japanese Patent Application Laid-open No. 56-10455.

JP-A-57-18254, JP-A-58-6282
A smooth film produced by coating and stretching has been proposed in Publication No. 6 and the like. These are made by applying a coating agent to a film that has been stretched longitudinally and axially, and then stretching it in the transverse direction, and because the protrusions of the coating layer are long in the longitudinal direction, the protrusions are called "worm-like protrusions."

It is described as a ``mountain-like protrusion'' (hereinafter abbreviated as a vertically long protrusion). Furthermore, as a special type of vertically long protrusions, "discontinuous film-like protrusions" in which the surface of the base polyester film is exposed due to breakage of the coating layer have also been proposed. Furthermore, in order to improve slipperiness, silicon-based compounds and fluorine-based compounds are added along with particles and longitudinal protrusion-forming agents using a coating and stretching method.

The combined use of polyolefin compounds and the like has been proposed.

[Purpose of the invention]

The present inventors first developed a polyester film (with excellent adhesiveness) having a coating layer consisting of polyurethane and polyvarnish
JP-A-58-78761), or a polyester film with excellent adhesiveness having a coating layer made of acrylic resin and polyester (JP-A-58-124651)
(Japanese Patent Publication), a polyester film with excellent slipperiness and adhesive properties (% Kaimei 60-6125
Publication No. 9, % 1986-65161 Publication 2% 1986
-65+62). An object of the present invention is to further improve the polyester properties of these polyester films, and to provide a polyester film with improved antistatic properties and coating strength.

[Structure of the invention]

The present inventors investigated particles or a specific anionic compound as a composition for polyurethane or acrylic resin, and found that the combination of these particles and a specific anionic compound, especially in the case of an ultra-flat base film. However, it was discovered that when a polyester film is produced by a coating and stretching method, the slipperiness is improved, leading to the present invention.

That is, the present invention provides an alkyl sulfonate and/or alkyl sulfate salt, particles, a polyurethane and/or acrylic resin having an anionic group, and optionally a polyester having an anionic group on at least one side of a polyester film. This is a polyester film that is coated with a coating solution consisting of the following, and then stretched.

The polyester of the polyester film constituting the substrate in the present invention is polyethylene terephthalate in which 80 moles or more of the constituent components are ethylene terephthalate, or polyethylene naphthalate in which 80 moles or more of the constituent components are ethylene naphthalate. Examples of polyester components other than ethylene terephthalate and ethylene naphthalate include diethylene glycol, propylene glycol, neopentyl glycol, 1,4-butylene glycol, 1°4-cyclohexane dimetatool, polyethylene glycol, and polytetramethylene glycol. Diol components, dicarboxylic acid components such as inphthalic acid, 5-diosulfoisophthalic acid, adipic acid, sebacic acid and its ester-forming derivatives, oxycarboxylic acids such as oxybenzoic acid and its ester-forming derivatives, etc. can be used. Yes, but not limited to these.

The polyester film constituting the substrate in the present invention may contain so-called additive particles or precipitated particles, a polyester having different properties from the polyester of the substrate, or a polymer other than polyester in order to form protrusions on the surface of the film. . The surface roughness of the base polyester film is determined by the type and size of the protrusion-forming agent depending on the required properties such as lubricity and transparency of the product in which the polyester film of the present invention is used.

This can be achieved by a method well known to those skilled in the art to select the amount to be added.

The composition other than the protrusion-forming agent for the polyester film constituting the base may include antistatic agents, stabilizers,
Lubricant, N colorant.

It may also contain a former WI blocker.

Orientation of the polyester film that makes up the substrate.

Properties such as crystallinity, mechanical properties, and dimensional stability can be achieved by selecting from film manufacturing conditions well known to those skilled in the art in accordance with the custom requirements of the product in which the polyester film of the present invention is used. The polyurethane having an anionic group in the invention is
In addition to acting as a binder for the alkyl sulfonate, alkyl sulfate salt, and particles, when a coating layer, printed layer, vapor deposition layer, etc. is formed on the coating layer of the polyester film of the present invention, it has the effect of improving adhesion. It is something that can be demonstrated. The polyurethane having an anionic group in the present invention is preferably water-soluble or water-dispersible.
Angew, Makromo'1. Chem...
98 133-165 (1981)% Special Public Interest Publication 1977-2
No. 4194.

Special Publication No. 46-7720, Special Publication No. 46-10193,
Special Publication No. 49-37859! Opening/closing 50-125197
No., JP-A-53-126058, JP-A-54-138
No. 098, JP-A-61-36314, JP-A-57-1
Publicly available polyurethane such as No. 25048 or a polyurethane similar thereto can be used.

The main components of the polyurethane-forming component are polyincyanate, polyol, chain extender, crosslinking agent, and the like.

Examples of polyinsyanates include tolylene diisocyanate, phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, 4,4'-
Examples of polyols are polyethers such as polyoxyethylene glycol, polyoxypropylene glycol, and polyoxytetramethylene glycol, polyethylene adipate, and polyethylene-butylene glycol. polyesters, polyesters such as polycaprolactone, acrylic polyols, and castor oil.

Examples of chain extenders or crosslinking agents include ethylene glycol, propylene glycol, butanediol, diethylene glycol, trimethylolpropane, hydrazine, ethylenediamine, diethylenetriamine, 4.
Examples include 4'-diaminodiphenylmethane, 4,4'-diaminodicyclohexylmethane, and water.

Polyurethane having an anionic group is a polyurethane forming component such as a polyol, a polyincyanate compound,
A method of using a compound having an anionic group as a chain extender, etc., a method of reacting an unreacted incyanate group of the produced polyurethane with a compound having an anionic group, a method of reacting a group having an active hydrogen of polyurethane with an anionic group. It can be produced by using a method of reacting a compound having the above.

In the method of using a compound having an anionic group as a polyurethane forming component, for example, a compound obtained by a method of sulfonating an aromatic incyanate compound, a diaminocarboxylic acid salt, a sulfuric acid ester salt of amino alcohols, etc. can be used.

The method of reacting an unreacted incyanate group of polyurethane with a compound containing an anionic group includes, for example, east sulfite, aminosulfonic acid and its salts, aminocarboxylic acid and its salts, sulfuric esters of amino alcohols and its salts, Hydroxyacetic acid and its salts can be used.

Examples of the compound having an anionic group to be reacted with the group having active hydrogen of polyurethane include dicarboxylic acid anhydride, tetracarboxylic acid anhydride, sultone, lactone,
Epoxycarboxylic acid, epoxysulfonic acid, 2,4-dioquine-oxazolidine, isatoic anhydride, hostone,
A 6- to 7-membered cyclic compound representing a salt-type group such as carpyl sulfate or a group capable of forming a salt after ring opening can be used.

In the case of polyester polyurethane, an anionic group can be introduced into the polyurethane by using a polyester having an anionic group. A polyester having an anionic group is one in which a compound having a sulfonic acid group or a carboxylic acid group is bonded to a dipolyester by copolymerization, craft polymerization, or the like.

The polyurethane is preferably a resin made of a polyol having a molecular weight of 600 to 20,000, a polyincyanate, a chain extender having a reactive hydrogen atom, a group that reacts with the incyanate group, and a compound having at least one anionic group.

The anionic group in polyurethane is -8o3H.

It is used as a lithium salt, sodium salt, potassium salt, magnesium salt, or ammonium salt such as -0803H1-COOH.

The amount of anionic groups in the polyurethane is preferably 0.05% by weight to 81M based on the polyurethane having anionic groups. If the amount of anionic groups is low, the water solubility or water dispersibility of polyurethane will be poor, and if the amount of anionic groups is high, the water resistance of the 9 layers of undercoat after application will be poor, and the films will tend to stick to each other due to moisture absorption. It is from.

The acrylic resin in the present invention not only serves as a binder for the alkyl sulfonate salt, alkyl sulfate salt, and particles, but also serves as a binder for the alkyl sulfonate salt, alkyl sulfate salt, and particles, and also forms a coating layer, a printed layer, a vapor deposition layer, etc. on the coating layer of the polyester film of the present invention. In some cases, it exhibits the effect of improving adhesion. The acrylic resin in the present invention is preferably a water-soluble resin or a water-dispersible resin containing methacrylate, alkyl acrylate, or alkyl methacrylate as a main component, and contains 60 to 90 mol of these components. A water-soluble A6 or water-dispersible resin containing 70 to 10 mol % of a copolymerizable vinyl monomer component having a functional group is preferred.

A vinyl monomer that can be copolymerized with alkyl acrylate or alkyl methacrylate and has a functional group imparts hydrophilicity to the resin and improves the water dispersibility of the resin.
Alternatively, it may have a functional group that improves the N-contact between the resin and the polyester film or other coating layers provided on the 9 undercoat layers, or improves the IFO affinity between the resin and the resin blended as a coating agent. Preferred functional groups are carboxyl groups or salts thereof, acid anhydride groups, sulfonic acid groups or salts thereof, amide groups or alkylolated amide groups, amine groups (including substituted amino groups), or alkylol groups. amine groups or salts thereof, hydroxide groups, epoxy groups, etc. Particularly preferred are carboxyl groups or salts thereof, acid anhydride groups, epoxy groups, and the like. Two or more types of these groups may be contained in the resin.

The reason why it is preferable that the alkyl acrylate or alkyl methacrylate in the acrylic resin is 60 molar or more is because the coating formability, the strength of the coating film, and the blocking resistance are improved. It is preferable that the amount of alkyl acrylate or alkyl methacrylate in the acrylic resin is 90 mole or less because it can be easily water-solubilized and water-dispersed by introducing a compound having a specific functional group into the acrylic resin as a copolymerization component. At the same time, in order to stabilize the state over a long period of time, we further improved the adhesion between the coating layer and the polyester film layer, coating 1-
This is because it is possible to improve the strength, water resistance, and chemical resistance of the coated layer due to the reaction within the film, as well as to improve the N-contact property between the film of the present invention and other materials.

Examples of alkyl groups in alkyl acrylates and alkyl methacrylates include methyl group, ethyl Nb n-
Examples include propyl group, inbutyl group, n-butyl group, inbutyl group, t-butyl group, 2-etherhexyl group, lauryl group, stearyl group, cyclohexyl group, and the like.

As the vinyl monomer having a functional group copolymerizable with alkyl acrylate or alkyl methacrylate, the following compounds having functional groups such as a reactive functional group, a self-crosslinking functional group, and a hydrophilic group can be used.

Examples of compounds having a carboxyl group or a salt thereof, or an acid anhydride group include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, metal salts of these carboxylic acids with sodium, ammonium salts, or Examples include maleic anhydride.

Examples of compounds having a sulfonic acid group or a salt thereof include vinyl sulfonic acid, styrene sulfonic acid, metal salts of these sulfonic acids with sodium, and ammonium salts.

Examples of compounds having an amide group or an alkylolated amide group include acrylamide, methacrylamide, N-methylmethacrylamide, methylolated acrylamide, methylolated methacrylamide, ureido vinyl ether, β-ureidoin butyl vinyl ether,
Ureido ethyl acrylate etc. are rejected.

Examples of compounds having an amine group or an alkylolated amino group or a salt thereof include diethylaminoethyl vinyl ether, 2-aminoethyl vinyl ether, 3-aminopropyl vinyl ether, 2-aminobutyl vinyl ether, dimethylaminoethyl methacrylate, dimethylaminoethyl Vinyl ethers, methylolated amino groups thereof, alkyl halides,
Examples include those converted into quaternary chlorides with dimethyl sulfate, sultone, etc.

Examples of compounds having a hydroxyl group include β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate,
β-Hydroxyguzolol acrylate, β-hydroxygzolol methacrylate, β-hydroxy vinyl ether, 5-hydroxypentyl vinyl ether, 6-hydroxyhexyl vinyl ether, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, polypropylene glycol monoacrylate, polypropylene glycol monoacrylate Examples include methacrylate.

Examples of the compound having an epoxy group include glycidyl acrylate and glycidyl methacrylate.

Furthermore, in addition to the above compounds, the following compounds may be used in combination. i.e. acrylonitrile, methacrylonitrile,
Styrenes, butyl vinyl ether, mono- or dialkyl maleic acid esters, mono- or dialkyl fumaric acid esters, mono- or dialkyl itaconic acid esters, methyl vinyl ketone, vinyl chloride, vinylidene chloride, ff [vinyl, vinyl pyridine, vinyl pyrrolidone, vinyl trimethoxy Examples include silane, but these are not enough.

The acrylic resin may contain a surfactant.

However, when the ratio of acrylic resin to polyester resin is high, the low molecular weight surfactant contained in the acrylic resin becomes concentrated during the film forming process and accumulates at the interface between particles. It may migrate to the interface of the coating layer, causing problems in the mechanical strength, water resistance, and adhesion to the laminate of the coating layer. In such a case, a polymer obtained by so-called glue-free polymerization that does not contain a surfactant can be used.

The method for producing acrylic resin that does not contain surfactants is as follows:
Edited by the Management Development Center Publishing Department, published by the Management Development Center Publishing Department in January 1982, page 389 of "Water-soluble polymer/water-dispersed resin comprehensive technical data collection" or sponsored by the Industrial Technology Research Group, "The latest research results ``Looking ahead to the future ~New developments in emulsions and future technical issues'' lecture text (1933)
(December 2006) can be used. For example, use of oligomers or polymeric surfactants instead of low molecular weight surfactants, introduction of hydrophilic groups into polymers by using polymerization initiators such as potassium persulfate or ammonium persulfate, and monomers having all hydrophilic groups. copolymerization of
The use of reactive surfactants and so-called shell-core polymers in which the compositions of the inner and outer layers of dispersion particles are changed have been developed as a manufacturing technology for water-dispersible acrylic resins that do not contain so-called surfactants. Can be used.

In the present invention, polyester having an anionic group is used to improve coatability, adhesion, and strength of the coated layer of the polyurethane and/or acrylic resin base film, and to form the coated layer of the polyester film of the present invention. It may be used as necessary to improve the formability of the laminated material and the adhesion after formation. The anionic group-containing polyester in the present invention is preferably water-bathable or water-dispersible, and the dicarboxylic brewing ingredients include aromatic dicarboxylic acids such as terephthalic acid, inphthalic acid, and 2,5-naphthalene dicarboxylic acid, and adipine. Acids, aliphatic dicarboxylic acids such as azelaic acid and sebacic acid, oxycarboxylic acids such as oxybenzoic acid, and ester-forming derivatives thereof can be used.

In the present invention, the glycol component of the polyester having an anionic group includes ethylene glycol, 1.4-
Aliphatic glycols such as phthanediol, diethylene glycol and triethylene glycol, alicyclic glycols such as 1,4-cyclohexane dimetatool, aromatic diols such as p-xylene diol, polyethylene glycols, etc.
J = + -k, poly(oxyalkylene glycols such as polypropylene glycol, polytetramethylene glycol, etc.) can be used.

In the present invention, the polyester having an anionic group 'kV' includes not only a saturated linear polyester comprising the above-mentioned ester-forming component, but also a compound having six or more ester-forming components or a compound having a reactive unsaturated group. A polyester component may also be used.

In the present invention, the anionic group of the polyester having an anionic group is a sulfonic acid, a carboxylic acid, or a salt thereof. The sulfonate and carboxylate salts include ammonium salts, amine salts such as methylamine and ethanolamine, and metal salts such as lithium, sodium, potassium, and magnesium. As a polyester having a sulfonic acid group, Japanese Patent Publication No. 47-40873
No., Japanese Patent Publication No. 50-85497.

JP-A-50-121536, JP-A-52-15564
Polyesters such as No. 0 or similar polyesters can be used. Methods for introducing sulfonic acid groups into polyester include sulfoinphthalic acid, sulfoterephthalic acid, 4-sulfonaphthalene-2,
7-Dicarboxylic acids and metal salts such as ester-forming derivatives thereof are added during the transesterification or polymerization process of polyesters to copolymerize them; unsaturation of polyesters copolymerized with ester-forming aliphatic unsaturated compounds; Methods include sulfonation of a styrene group with a sulfonating agent such as hydrogen sulfite or sodium metasulfite, and a method of grafting styrene sulfonate, methacryl sulfonate, etc. onto polyester using a radical initiator. be. Methods for introducing carboxylic acid groups into polyester include the method of reacting a dioxy compound having a carboxylic acid group with polyester as shown in JP-A-61-228030, and the method of reacting acrylates, methacrylates, etc. with radicals. This article will discuss how to introduce it into polyester using an initiator, etc.

The amount of anionic group in the polyester is preferably 1% to 10% by weight based on the weight of the sulfonic acid group or carboxylic acid group based on the total polyester. If the amount of anionic groups in the polyester is less than 1% by weight, the water solubility and dispersibility of the polyester will be insufficient, and if it is more than 10% by weight, the water resistance of the coated layer after coating will be affected. tends to decrease.

As the polyester having an anionic group in the present invention, one modified by grafting a compound having a carbon double bond having a silicon group, a fluorinated alkyl group, an epoxy group, an amide group, etc. may be used.

The molecular weight of the anionic group-containing polyester that can be used in the present invention is preferably 5,000 to 50,000. Dainippon Ink Chemical Co., Ltd. is a commercially available polyester having an anionic group.

Products manufactured by Nippon Gosei, Toyobo, Gooh Kagaku, Takamatsu Yushi, etc. can be used, but are not limited to these.

The alkyl sulfonate or alkyl sulfate salt in the present invention has the structural formula R803M or RO8O3M. Here, R preferably has 8 to 60 carbon atoms. When the number of carbon atoms is less than 8, the compatibility with the resin to be blended is poor, and the effect of improving lubricant injection is often not effective, probably because the so-called blooming effect is small, and the effect of improving antistatic properties is also small.

If the number of carbon atoms is greater than 30, the proportion of sulfonic acid groups effective in preventing static electricity decreases, so it is necessary to increase the amount of this compound mixed in. In such cases, the polyester film of the present invention may be applied. The adhesion of the layer may be reduced. In the structural formula, R may have an aromatic group having a saturated aliphatic alkyl group, but preferably,
It is a saturated aliphatic straight chain or branched alkyl group.

In the structural formula, M is ammonium group, potassium metal Li, N
a, K 7%, and preferably Na.

In the present invention, the proportion of the alkyl sulfonate or alkyl sulfate salt in the coating layer is preferably 2 w
t% to 30 wt%), more preferably 5 w
t% to 20 wt%. If the amount of this compound is less than 2 wt%, the slip property or antistatic effect will not be significant, and even if the amount is increased by 30 wt%, the slip property or antistatic effect will not necessarily be further improved. The N-contact properties of the coating layer of the polyester film of the present invention may deteriorate, or the film may become sticky.

The particles in the present invention may be inorganic particles, organic particles, organic/inorganic composite particles, or may have a hollow structure. Inorganic particles include silica, silica sol, alumina, alumina sol, zirconium sol,
Examples include, but are not limited to, kaolin, Merck, calcium carbonate, titanium oxide, barium salt, carbon, molybdenum sulfide, antimony oxide sol, and so-called conductive metal particles. Organic particles include those obtained by completely pulverizing and classifying polymers, those obtained by dissolving in a solvent and mixing with a poor solvent to precipitate particles, and those obtained by growing particles during the polymerization process.
You can use the precipitated material. Commercially available organic particles include, but are not limited to, benzoguanamine, silicon, fluororesin, styrene-acrylic resin, acrylic resin, epoxy resin, and nylon resin. :w@ and inorganic composite particles can be, for example, those obtained by repeating acrylic resin as a silica sol and core using a so-called seed polymerization method, or those obtained by precipitating an inorganic compound or a metal compound on organic particles. , but not limited to these.

The particle size of the particles in the present invention varies depending on the thickness of the coating layer, the required slipperiness and transparency of the film, the recording accuracy in information recording applications, etc., but is preferably [LD1μ~
5μ, more preferably Q, 02μ to 1μ. If the particle size of the particles in the present invention is less than 1.01 μm, it is often not effective in improving lubricity, and if it is larger than 5 μm, deterioration of transparency etc. may be observed. In the present invention, it is preferable to use particles with a narrow particle size distribution, since this makes it easier to control the surface shape of the coating layer. Recently, monodispersed particles have become available, and particles with different particle sizes may be combined to design a particle system with a particle size distribution depending on the application and used in the coating layer.

The proportion of particles in the coating layer in the present invention is preferably 1% by weight to 70% by weight, more preferably 2% by weight.
~60 weight it%T6. If the amount of particles in the coating layer is less than 1% by weight, the effect of improving slipperiness will be small, especially if the base film is flat, and if it is more than 70% by weight, the strength of the coating may decrease.

Depending on the type of particles of the present invention, due to the type of surface functional group or ionicity, polyurethane having an anionic group, polyester having an anionic group, acrylic resin, alkyl sulfonate or alkyl sulfate may be used. May aggregate with ester salts. In such cases, it is preferable to pay attention to the mixing order of the particles and other components, or to form a protective layer by introducing a specific low-molecular compound or polymer onto the p-particle surface through reaction or adsorption. The coating liquid used in the invention includes a methylolated or alkylolized urea-based, melamine-based, or guanamine-based crosslinking agent to improve the adhesion (blocking property), water resistance, bath agent resistance, and mechanical strength of the coating layer. , acrylamide-based, polyamide-based compounds, epoxy compounds, aziridine compounds, block polyinsyanates, silane coupling agents, titanium coupling agents, zirco-aluminate coupling agents, heat, peroxides, ex-reactive vinyl compounds or a photosensitive resin. Also,
Antifoaming agents, coating improvers, thickeners, and antistatic agents as required.

It may contain an organic lubricant, an anti-singing agent, an ultraviolet absorber, a foaming agent, a dye, a pigment, and the like.

Further, the coating solution of the present invention may contain polymers other than the polymers of the present invention for the purpose of custom improvement of the entire coating solution or the coating layer.

As a method for applying the above-mentioned coating liquid to a polyester film, there is a reverse roll coater as shown in "Coating Method" written by Yuji Harasaki, published by Maki Shoten, 1979,
A method in which a coating solution is applied to an unstretched polyester film using a Clavia coater, a rod coater, an air doctor coater, or other coating equipment, and then biaxially stretched sequentially or simultaneously; , a method in which the film is first stretched in a direction perpendicular to the uniaxial stretching direction, and a method in which the film is coated on a circular or biaxially stretched polyester film and further stretched in the transverse and/or longitudinal direction.

The above-mentioned stretching step is preferably carried out at 60 to 130°C, and the stretching ratio is at least 4 times or more in terms of area ratio, preferably 6 to 20 times.

The stretched film is heat treated at 150-250°C.

Furthermore, in the maximum temperature zone of the heat treatment and/or the cooling zone of the heat treatment outlet, the temperature is 0.2 to 20 in the longitudinal and transverse directions.
% relaxation is preferred.

In particular, coating G is applied to a uniaxially stretched polyester film that has been stretched 2 to 6 times by the roll stretching method at 60 to 160°C, and then dried appropriately, or the polyester uniaxially stretched polyester film is coated without drying. Immediately, it was abrasively stretched 2 to 6 times at 80 to 130°C in a direction perpendicular to the previous stretching direction, and
A method in which heat treatment is performed at ~250°C for 1 to 600 seconds is preferred.

According to this method, it is possible to dry the coating layer at the same time as stretching, and the thickness of the coating layer can be reduced according to the stretching ratio, and a film suitable as a polyester film base material can be produced at a relatively low cost. can.

Coating g in the present invention may be applied to only one side of the polyester film, or may be applied to both sides. When the polyester film of the present invention is coated only on one side, a coating other than the coating solution of the present invention may be applied to the opposite side, if necessary, to impart all other properties to the polyester film of the present invention.

In order to improve the applicability and adhesion of the coating agent to the film, the film may be subjected to chemical treatment or discharge treatment before coating. Also, the adhesion of the biaxially stretched polyester film of the present invention to the coating layer.

In order to improve coating properties, etc., the coating layer may be subjected to a roughening treatment after the coating layer is formed.

The polyester film coated with the coating ff' of the present invention obtained as described above preferably has a thickness of 3 to 500μ, and the thickness of the coating layer ranges from [L01μ to 5μ]. Preferably, Q is in the range of 02μ to 1μ. If the thickness of the coating layer is less than 0.01μ, it will be difficult to obtain a uniform coating layer and the product will likely have uneven coating.If it is thicker than 5μ,
Qing! This is undesirable because the lability is reduced and the film becomes difficult to handle.

Hereinafter, the present invention will be explained based on examples.

In addition, evaluation in Examples is based on the following method.

+11 Film base Measured according to JISK67+4 using an integrating sphere turbidity meter NDH-20D (trade name) manufactured by Nippon Denshoku Industries.

(2) Slip property The coefficient of friction between films was measured according to ASTM D 1sq4.63.

(3) Antistatic property A, charge attenuation property Static Honest Meter by Anato Shokai (product name)
A voltage of 10 kV is applied to the discharge electrode located 2 m above the sample in an atmosphere of 23° C. and 50% RH to charge the film, and the discharge is stopped after the band reaches saturation.

Thereafter, the charge decay property of the sample is measured with an electrometer placed 2 cm above the sample, and the half-life is determined.

5 seconds or less Very good 5-30 seconds Good 60-600 seconds Fairly good 600 seconds or more Poor In addition, if the charge decay property of the sample charged by the above method is poor, the sample should be filled with air at 35°C and 100% RH for 1 hour. Spray for seconds and evaluate whether any charge remains (forced humidification method).

B1 surface resistivity 16008A, a concentric circular electrode with a diameter of 50 m for the inner electrode and a diameter of 70 mm for the outer electrode, manufactured by Yokogawa/Heuret/Paracard.
(product name) at 23℃.

The sample is placed in an atmosphere of 50% RH, a voltage of 100 μ is applied, and the surface resistivity of the sample is measured using the company's high resistance meter 4329A (trade name).

(4) Workability When the film is slit and rolled into a roll, the appearance of the roll is good with no so-called marks or step shifts, and whether the film is charged with static electricity when unwound from the roll. (5) Coating film strength HEIDON-14 measured with a surface properties measuring machine manufactured by Shinraikagaku Co., Ltd.
(trade name), the load was varied on a sapphire needle with a diameter of L25W, and the measurement was performed at a scratching speed of 100 tan/min. The load at which the coating layer peels off from the base polyester is determined by taking a surface photograph of the film after the scratch test using a microscope.

Examples 1-4. Comparison 1+IJ 1-5 Thyroid, which is silica particles manufactured by Fuji Devison Co., Ltd.
266 (trade name) t-j Polyethylene terephthalate with an intrinsic viscosity of 0.66 containing t-j Oppm is heated at 280°C to 6
The mixture was melt-extruded at a temperature of 00°C and cast onto a cooling drum using an electrostatic adhesion method to obtain an amorphous film with a thickness of 820μ.

This film was stretched 56 times in the longitudinal direction at 95°C, and one side of the film was coated with each of the following coating solutions A to 1.
Stretched 53 times in the transverse direction at 10°C and heat treated at 210°C to form a coating layer with a thickness of 0.08μ and a base film with a thickness of 75μ.
A biaxially stretched polyester film of μ was obtained. The haze of this film, the coefficient of static friction between the coated layer surface and the non-coated layer surface,
Table 1 shows the coating film strength, charge decay property, surface resistivity, and workability.

As seen in Table 1, the combination of polyurethane and/or acrylic resin with alkyl sulfonate and particles
In case C, the polyester film can be smoothed without deteriorating its transparency! It can be seen that the antistatic properties and antistatic properties are improved. The reason why alkyl sulfonate increases the strength of the coating film in the scratch test method is thought to be because it reduces the frictional resistance with the scratching needle, as it improves the coefficient of static friction. In other words, the polyester film of the present invention has transparency,
Useful for applications where anti-static properties and anti-static properties are required.

Coating liquids A to A are mixtures of the following coating agents 1 to 2 in the parts shown in Table 2.0 Note that the parts are shown in terms of solid weight (the same applies hereinafter).

(1) Hytran AP-40 (product name), a polyurethane with an anionic group manufactured by Dainippon Ink and Chemicals Co., Ltd. (It) Finetex EB-670 (product name), a polyester manufactured by Dainippon Ink and Chemicals Co., Ltd. l
Nippon Junrakusha's acrylic resin Jurimar AT-M91
8 (Product name) (v) Surface adsorption treatment of silica sol Ruru Snowtex YL (Product name) manufactured by Hinami Kagaku Kogyo Co., Ltd. with water-soluble resin (V) Latemul PS, an alkyl sulfonate manufactured by Kao Corporation (Product name) (B) Alkylol melamine Comparative Example 6 Coating solution A of Example 1 was applied to the biaxially stretched polyester film without the coating layer of Comparative Example 5, dried at 80°C for 2 minutes, and the coating layer was A film with a thickness Q of 08μ was obtained. The haze of this film is 0.6%, the coefficient of static friction is α63,
The surface resistivity was 1×+013. The reason why the static friction coefficient and surface resistivity of this film are poor compared to the coating and stretching method is that - under the drying conditions used for boat fishing, the alkyl sulfonate does not bloom sufficiently on the surface. It is assumed that.

Example 5 The composition was the same as that of coating liquid A in Example 1, except that Snowtex YL (trade name), which is a component of coating liquid A in Example 1, was blended with silica sol without adsorption treatment on the surface with a water-soluble resin. l
A biaxially stretched polyester film having a coating layer thickness of 108 μm was obtained in the same manner as in Example 11. The haze of this film is 2
．． 6%, static friction coefficient [130, surface specific resistance 5
The film base was slightly higher because, according to observation using an electron microscope, the particles were a little agglomerated.However, this film does not require particularly high transparency. In terms of applications, its anti-slip and anti-static properties.

It is useful because of its adhesion-improving effect.

Example 6 A polyethylene terephthalate film having an intrinsic viscosity of 0.64 and containing almost no surface protrusion forming agent based on polymerization catalyst residue etc. was melt-extruded onto a cooling drum at 1280°C to 300°C, and was then melt-extruded at 85°C in the longitudinal direction. Stretched 55 times with a roll,
The film is then subjected to discharge treatment and rough static neutralization treatment, and one side of this film is coated with anionic polyurethane manufactured by Dainippon Ink and Chemicals Co., Ltd.
0 (trade name) 70 parts, Pesresin A317G (trade name), a polyester having an epoxy group manufactured by Takamatsu Yushi Co., Ltd.
2 oi, 5 parts of Snowtex YL (trade name), a silica sol manufactured by Nichiryo Kagaku Kogyo Co., Ltd. whose surface has been adsorbed with a water-soluble resin, sulfate ester sodium salt whose alkyl group is a saturated aliphatic group with 12 carbon atoms A coating layer consisting of 5 parts was applied. Furthermore, this film was heated at 110°C for 5
Stretched 5 times and heat treated at 220°C to reduce the thickness of the coating layer to 1.
A biaxially stretched polyester film having a thickness of 0.04μ and a base film thickness of 12.1μ was obtained. The surface roughness of this film was measured using a thin film profilometer E, which is a stylus-type surface roughness meter manufactured by Koita Research Institute.
Measured using T-10 type (trade name) with stylus tip radius LL5μ, stylus load 60μ, and running speed α11Ill/sec.
The surface roughness according to the maximum height definition of JIS BO601-1982 is 12OA on the surface without the coating layer.

The surface of the coating layer was 18OA. The coefficient of static friction between the coated layer surface and the surface without the coated layer of this film is [L53. The dynamic friction coefficient was α48. This film was a success because it allowed a wide range of film roll winding conditions in the winding process after slitting, and the winding appearance was good. Furthermore, when the film was unwound from the roll, the film could be unwound quickly. On the other hand, in this example, a biaxially stretched polyester film was obtained without applying the coating liquid, but the appearance of the winding roll after slitting was extremely poor.
Also, when unwinding the film from this roll, due to the film's electrical charge, the films tend to block each other.
In some cases, spark discharge occurred or the film broke at the unwinding part.

That is, the polyester film of the present invention improved the running properties of the polyester film with extremely high flatness and made it easier to handle. Latemul P, an alkyl sulfonate manufactured by Kako Co., Ltd.
The coating layer obtained in the same manner as in Example 6 except that S (trade name) was used had a thickness of 1105 μm, and the thickness of the base film was 4.5 μm.
The 0μ biaxially stretched polyester film is a polyester film with extremely high flatness, has improved running properties, and is easy to handle.

Example 8 Polyethylene terephthalate with intrinsic viscosity Q of 64) k28
Melt extrusion was carried out on a cooling drum at a temperature of 0°C to 300°C to obtain a 50μ thick non-woven film. This film is 95
It was stretched in the longitudinal direction at ℃, and then Jurimar AT-M918 Kai 4 (local product name), which is an acrylic resin manufactured by Nihon Tsumugi Co., Ltd.
45 parts of Hytran HW-310 (trade name), a polyurethane manufactured by Dainippon Ink and Chemicals, 40 parts of Snowtex YL (trade name), a silica sol manufactured by Nichiryo Chemical Co., Ltd.
5 parts of product name) treated with surface adsorption with water-soluble polymer,
Latemul PS manufactured by Kako Co., Ltd. with alkyl sulfonate (
Product name) Apply coating g consisting of 10 parts, and then apply 110 parts
The film was stretched 55 times in the transverse direction at 0.degree. C. and heat treated at 215.degree. C. to obtain a biaxially stretched polyester film having a coating layer thickness of 0-05 .mu.m and a base polyester film thickness of 4.1 .mu.m.

The coefficient of static friction between the surfaces of this film that does not have a coating layer is (L34. The coefficient of static friction between the surface of the coating layer and the surface that does not have a coating layer is [130]. Although this film is thin and weak, Because the film has good slipperiness and is not electrostatically charged, it rarely causes problems in the handling process of the '!r building, and is a useful film that rarely occurs.Example 9 Polyethylene terephthalate with an intrinsic viscosity of 0.65
Melt extrusion at 0°C to 300°C, cast on a cooling drum using both electrostatic adhesion method, and vertically roll 3.
It was stretched 5 times. On one side of this film, an average particle size of 0.20
50 parts of μ calcium carbonate particles, 5 parts of alkylol melamine, 5 parts of Latemul PS (trade name), an alkyl sulfonate manufactured by Kako Co., Ltd., 30 parts of polyurethane having a carboxylic acid group as an anionic group, having an epoxy group A coating g consisting of 10 parts of polyester was applied, further stretched 5.5 times in the transverse direction, heat treated at 210°C, and biaxially stretched to a coating layer thickness of 146μ and a base film thickness of 14.3μ. I got polyester film. The surface roughness of this film was measured using a contact type surface roughness meter manufactured by Koita Research PyT, 5urfcorder SF-3F (product name).
So, PUDJ as a stylus 2. Using Oti diameter, stylus load 60m9, traveling speed α+ff1l+l/Sec
4 Measurements were made with a foot length of 2.5 m, a cutoff value of Q, and a length of 08. As defined by JIS BO60+-1982, the center line average roughness Ra, maximum height Rmax, and ten point average roughness RZ are CL if this film does not have a coating layer.
O+ 4μ, α226μ20, +79μ, and the coated layer surface of this film is [1L061μ, 0.325μ], respectively.
/J, i at 1283μ. The coating strength of this film is 5
01 or higher, and had high strength, and there was no peeling of the coating layer or transfer to the roll even during calender treatment. Moreover, this film was not charged with electricity during the calendering process and was a film with good workability.

[Effects and uses of the invention]

The polyester film of the present invention has a coating layer made of polyurethane or acrylic resin.
Not only does it have a surface with good N contact properties, but it also has excellent slip properties and antistatic properties, and in some cases, it has improved slip properties without reducing transparency! 7. For plate making and magnetic recording.

It can be used for various purposes including vapor deposition and thermal transfer.

Patent applicant: Diafoil Co., Ltd.

Claims (1)

[Claims] 1. At least one side of the polyester film consists of (1) an alkyl sulfonate and/or an alkyl sulfate salt and (2) a polyurethane and/or acrylic resin having an anionic group, and (3) contains fine particles. A polyester film coated with a coating solution and then stretched.