JPH0463095B2 - - Google Patents

Description

[Detailed description of the invention]

(Field of Industrial Application) The present invention relates to a flexible vinyl chloride resin film for agricultural use, and more particularly to a flexible vinyl chloride resin film for agricultural use with improved spinnability. (Conventional techniques and their problems) Recently, farmers who cultivate useful plants have been trying to cultivate useful plants in greenhouses or tunnels to promote or suppress cultivation in order to improve profitability.
It has become widely adopted. As coating materials for agricultural greenhouses or tunnels, polyethylene films, ethylene-vinyl acetate copolymer films, polyester films, polycarbonate films, vinyl chloride resin films, glass, etc. are used. Among them, vinyl chloride resin films, especially soft vinyl chloride resin films containing a large amount of plasticizer, have better light transmittance, heat retention, mechanical strength, and durability than other synthetic resin films, glass, etc. It is widely used because it is the best overall in terms of workability, economy, etc. However, when a soft vinyl chloride resin film is used to cover a greenhouse or tunnel, the inside surface of the greenhouse becomes cloudy, which impairs the penetration of sunlight, slowing down plant growth, and causing water droplets to fall onto cultivated plants. This can cause damage to young shoots and cause disease. In order to eliminate such inconveniences, it is known that antifogging properties may be imparted to the surface of the soft vinyl chloride resin film. To impart antifogging properties to the surface of a soft vinyl chloride resin film,
A method of kneading a hydrophilic substance such as a surfactant into a soft vinyl chloride resin and forming it into a film, or a method of coating the surface of the film with a hydrophilic substance or a water-soluble polymer substance is adopted. has been done. However, in the former method, the hydrophilic substance kneaded into the soft vinyl chloride resin exudes onto the film surface and coordinates, giving the film antifogging properties, but it is washed away by water. The anti-fog properties deteriorate over time. To solve this problem, for example, Japanese Patent Publication No. 46-13252, Japanese Patent Application Publication No. 49-70885, and Japanese Patent Application Publication No. 50-71770 disclose a method of applying a water-soluble hydrophilic substance such as polyvinyl alcohol; Also, Special Publication No. 50-6437,
Japanese Patent Publication No. 53-37075 proposes a method of applying a composition comprising a hydrophilic polymer containing hydroxyalkyl acrylate as a main component, a surfactant, etc. However, these hydrophilic substances are susceptible to hydrolysis and therefore have poor water resistance, and also have poor adhesion to hydrophobic soft vinyl chloride resins. Particularly under humid conditions, coatings derived from these hydrophilic substances It easily peels off from the resin film surface, and cannot exhibit sufficient antifogging performance. In order to improve these shortcomings, for example,
No. 56-34219 proposes a method of making a hydrophilic acrylic ester polymer containing a hydroxy group insoluble in water using a crosslinking agent. However, according to this method, the antifogging property itself also decreases, so it cannot be said to be a satisfactory improvement method. On the other hand, a method of applying a mixture of an inorganic aqueous sol and a surfactant has been proposed as a method for imparting hydrophilicity. For example, Japanese Patent Publication No. 50-11348 discloses a product containing a surfactant as the main ingredient with a small amount of silica gel added, and Japanese Patent Publication No. 49-32668 discloses
Alumina sol with surfactant added, JP-A-Sho
Publication No. 58-29831 describes a product in which a small amount of water-soluble aluminum salt is added to coloridal silica. However, since these mixtures have poor adhesion to the organic soft vinyl chloride resin, the formed coating film falls off over time, making it impossible to maintain the antifogging effect over a long period of time. In order to improve the above drawbacks, for example, JP-A-51-
Publication No. 81877 describes a product in which a surfactant and a hydrophilic polymer are added to an alumina sol, JP-A-57-
Publication No. 119974, Japanese Patent Publication No. 57-187347, Publication No. 187347, Japanese Patent Publication No. 187347
No. 59-15473 discloses colloidal silica containing a hydrophilic polymer and a surfactant. However, since these compositions contain hydrophilic polymers such as polyvinyl alcohol and hydroxyl group-containing acrylic resins for the purpose of achieving miscibility with inorganic aqueous sols, the formed coating films are inherently inferior in water resistance. Tend. Therefore, if constantly exposed to humid conditions, the inorganic aqueous sol will be washed away together with the hydrophilic polymer or will be poorly dispersed, and the antifogging effect will be lost in a short period of time, making it unsatisfactory for practical use. Furthermore, in order to improve the above-mentioned drawbacks, for example, JP-A No. 55-99976 and JP-A No. 55-99987 disclose prevention using an inorganic-organic composite reactant consisting of silica/hydrophilic polymer/organosilicon compound. A method of imparting haze has been proposed. However, even with these methods, the water resistance of the formed coating film is not sufficient, and the antifogging performance is not yet satisfactory, so that the intended purpose cannot be fully achieved. (Means for Solving the Problems) The present inventors aimed to solve the above-mentioned conventional drawbacks and provide a soft vinyl chloride resin film that exhibits excellent water resistance and antifogging properties over a long period of time. As a result of intensive study, we have completed the present invention. That is, the gist of the present invention is that (a) 60 to 100% by weight of an alkyl ester of acrylic acid or methacrylic acid is added to one or both sides of a soft vinyl chloride resin film containing an ultraviolet absorber and an organic phosphate ester; or a mixed monomer of alkyl esters of acrylic acid or methacrylic acid and alkenylbenzenes, and other α,β-ethylenic monomers that can be copolymerized with 0 to 40% by weight of the above monomers. (b) one or more types of water-based emulsion of a hydrophobic acrylic resin having a glass transition temperature in the range of 35 to 80°C obtained by emulsion polymerization with an unsaturated monomer; and (b) one type of inorganic colloidal sol. or two or more (a)
and (b) coating an antifogging agent composition containing a mixture of two components or an antifogging agent composition containing a mixture of the two components (a) and (b) above, a crosslinking agent, and/or a liquid dispersion medium. The invention consists in a soft vinyl chloride resin film for agricultural use. The present invention will be explained in detail below. The vinyl chloride resin, which is the main material forming the film of the present invention, includes not only polyvinyl chloride but also copolymers containing vinyl chloride as a main component. Monomers that can be copolymerized with vinyl chloride include vinylidene chloride, ethylene, propylene,
Examples include acrylonitrile, vinyl acid, maleic acid, itaconic acid, acrylic acid, methacrylic acid, but are not limited to these examples. The vinyl chloride resin may be manufactured by any of the conventionally known manufacturing methods such as suspension polymerization, emulsion polymerization, emulsion-suspension polymerization, solution polymerization, and bulk polymerization. The degree of polymerization of the vinyl chloride resin can be selected from the range of 800 to 2,500. The agricultural soft vinyl chloride resin film according to the present invention contains at least an ultraviolet absorber and an organic phosphate ester. Examples of the ultraviolet absorbent used here include the following. 2- which is a cyanoacrylate ultraviolet absorber
Ethylhexyl-2-cyano-3,3'-diphenyl acrylate, ethyl-2-cyano-3,3'-
Diphenyl acrylate. 2-Hydroxy-4-methoxybenzophenone, 2,4- which is a benzophenone ultraviolet absorber
Dihydroxybenzophenone, 2-hydroxy-
4-n-octoxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2,2-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-benzoyloxy Benzophenone, 2,2'-dihydroxy-methoxybenzophenone, 2-hydroxy-
4-methoxy-5-sulfonebenzophenone,
2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-5-chlorobenzophenone, bis(2-ethoxy- 4-Hydroxy-5-benzoylphenyl)methane. 2- which is a benzotriazole ultraviolet absorber
(2′-hydroxyphenyl)benzotriazole,
2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5-
methylphenyl)-5-carboxylic acid butyl ester benzotriazole, 2-(2'-hydroxy-
5'-methylphenyl)-5,6-dichlorobenzotriazole, 2-(2'-hydroxy-5'-methylphenyl)-5-ethylsulfonebenzotriazole, 2-(2'-hydroxy-5'-t-butylphenyl) )-5-chlorobenzotriazole, 2
-(2'-hydroxy-5'-t-butylphenyl)
Benzotriazole, 2-(2'-hydroxy-
5′-aminophenyl)benzotriazole, 2-
(2'-hydroxy-3',5'-dimethylphenyl)benzotriazole, 2-(2'-hydroxy-3',
5'-dimethylphenyl)-5-methoxybenzotriazole, 2-(2'-methyl-4'-hydroxyphenyl)benzotriazole, 2-(2'-stearyloxy-3',5'-dimethylphenyl) )-5
-Methylbenzotriazole, 2-(2'-hydroxy-5-carboxylic acid phenyl)benzotriazole ethyl ester, 2-(2'-hydroxy-
3'-Methyl-5'-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-
t-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-5'-methoxy phenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5
-chlorobenzotriazole, 2-(2'-hydroxy-5'-cyclohexylphenyl)benzotriazole, 2-(2'-hydroxy-4',5'-dimethylphenyl)-5-carboxylic acid benzotriazole butyl ester , 2-(2'-hydroxy-3',
5′-dichlorophenyl)benzotriazole, 2
-(2'-hydroxy-4',5'-dichlorophenyl)
Benzotriazole, 2-(2'-hydroxy-3',
5'-dimethylphenyl)-5-ethylsulfonebenzotriazole, 2-(2'-hydroxy-4'-
octoxyphenyl)benzotriazole, 2-
(2'-hydroxy-5'-methoxyphenyl)-5-
Methylbenzotriazole, 2-(2'-hydroxy-5'-methylphenyl)-5-carboxylic acid ester benzotriazole, 2-(2'-acetoxy-5'-methylphenyl)benzotriazole. Although the above-mentioned ultraviolet absorbers can be used, it is preferable to use benzophenone-based ultraviolet absorbers or benzotriazole-based ultraviolet absorbers. These ultraviolet absorbers can be used alone or in combination of two or more, and the amount used is 0.01 to 5 parts by weight, preferably 0.05 to 2 parts by weight, per 100 parts by weight of the vinyl chloride resin. If the amount used is too small, the desired anti-fog durability improvement effect will not be achieved.
On the other hand, if the amount is too large, not only will the effect of improving anti-fogging durability be not so great considering the amount used, but also the ultraviolet absorber will bleed onto the film surface, reducing the transparency of the film, which is undesirable. In the present invention, the inclusion of an ultraviolet absorber in a vinyl chloride resin film means that it is blended in advance into a resin composition before film molding, and this mixture is made into a film, or that UV absorbers are applied to the film surface after film molding. Refers to something coated with an absorbent.
When coating the surface of the latter base film, an ultraviolet absorber may be added to the coating film components and applied. Both of the above-mentioned means of blending the ultraviolet absorber into the resin composition before film formation and means of applying it after film formation may be used in combination. Examples of organic phosphoric acid esters to be included in the film of the present invention include triisopropylphenyl phosphate, isodecyl diphenyl phosphate, tricresyl phosphate, tris(isopropylphenyl) phosphate, tributyl phosphate,
Examples include triethyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, octyl diphenyl phosphate, and tricylenyl phosphate, among which tricresyl phosphate and tricylenyl phosphate are particularly preferred. . These are generally plasticizers for vinyl chloride resins and improve the weather resistance of the film. These organic phosphoric acid esters may be used alone or in combination of two or more, and the amount used is 0.5 to 10 parts by weight, preferably 1 to 7 parts by weight, per 100 parts by weight of the vinyl chloride resin. If the amount used is too large or too small, the desired effect of improving antifogging durability cannot be obtained. The agricultural vinyl chloride resin film according to the present invention may contain various additives commonly used for vinyl chloride resins, if necessary. For example, for 100 parts by weight of vinyl chloride resin,
Approximately 30 to 60 parts by weight of liquid plasticizer may be incorporated. Furthermore, other resin additives such as lubricants, heat stabilizers, antioxidants, stabilizing aids, antistatic agents, antifogging agents, antifungal agents, antialgae agents, colorants, etc. may be added as necessary. I can do it. Examples of lubricants, heat stabilizers, and antioxidants that can be incorporated into the film of the present invention include polyethylene wax, liquid paraffin, metal salts of organic acids, organic phosphorite compounds, β-dikedone compounds, and piperidine-based hindered amine compounds. etc. can be mentioned. The above various resin additives can be used alone or in combination. The amount of the various resin additives mentioned above can be selected within a range that does not deteriorate the properties of the film, usually within a range of 5 parts by weight or less based on 100 parts by weight of the base vinyl chloride resin. To blend the ultraviolet absorber, organic phosphate ester, and other resin additives into the vinyl chloride resin that serves as the base of the film, weigh the necessary amounts of each,
Ribbon blender, Banbury mixer, super mixer and other conventionally known compounding machines,
You can use a mixer. In order to form a film from the resin composition obtained in this way, a method known per se can be used, such as melt extrusion molding method (including T-die method and inflation method), calender molding method, solution casting method. etc. The film formed in this way is coated on the side of the film that is not coated with the antifogging liquid according to the present invention, in order to improve the dustproof property, antifogging property, high weather resistance, and blocking resistance of the film. other resins,
For example, a coating layer made of acrylic resin, fluorine resin, or polyolefin resin may be provided. It goes without saying that the above-mentioned ultraviolet absorber may be included in this coating layer. The hydrophobic acrylic resin that is a component of the antifogging agent composition used in the present invention has a molecular weight of 60 to 100%.
% by weight of alkyl esters of acrylic acid or methacrylic acid [hereinafter, this will be abbreviated as (meth)acrylic acid alkyl ester acid. ], or a mixed monomer consisting of (meth)acrylic acid alkyl esters and alkenylbenzenes, and α, β that can be copolymerized with 0 to 40% by weight of the above monomer and copolymer.
- It is a copolymer obtained by emulsion polymerization of an ethylenically unsaturated monomer in an aqueous medium in the presence of a surfactant. Examples of the (meth)acrylic acid alkyl esters used in the present invention include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, and n-acrylate.
Butyl, 2-ethylexyl acrylate, decyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, ethylhexyl methacrylate, decyl methacrylate, etc. Generally, acrylic acid alkyl esters having an alkyl group having 1 to 20 carbon atoms and/or methacrylic acid alkyl esters having an alkyl group having 1 to 20 carbon atoms are used. Examples of the alkenylbenzenes used in the present invention include styrene, α-methylstyrene, and vinyltoluene. Such alkenylbenzenes and (meth)
When using a monomer consisting of a mixture with acrylic acid alkyl esters, (meth)acrylic acid The proportion of alkyl esters is preferably 10% by weight or more. The hydrophobic acrylic resin preferably contains alkenylbenzenes in an amount of 70% by weight or less. In the hydrophobic acrylic resin of the present invention, monomers consisting of alkyl (meth)acrylates or a mixture of alkyl (meth)acrylates and alkenylbenzenes as described above are all monomers to be polymerized. If the content is less than 60% by weight, the formed coating film will not have sufficient water resistance and will not exhibit lasting antifogging performance. Other copolymerizable α,β- used in the present invention
Ethylenically unsaturated monomers include, for example, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, crotonic acid, itaconic acid, etc.
β-ethylenically unsaturated carboxylic acids; α,β-ethylenically unsaturated sulfonic acids such as ethylene sulfonic acid; 2-acrylamido-2-methylpropanoic acid; α,β-ethylenically unsaturated phosphonic acids; (meth) These include hydroxyl group-containing vinyl monomers such as hydroxyethyl acrylate; acrylonitriles; acrylamides; and glycidyl (meth)acrylate esters. These monomers may be used alone or in combination of two or more types, and may have a concentration of 0 to 40
It can be used in a range of % by weight. If it exceeds 40% by weight, it is not preferable because it reduces the antifogging performance. Water-based emulsion of hydrophobic acrylic resin is
It can be produced by a conventional emulsion polymerization method. For example, it can be obtained by subjecting the above monomers to emulsion subpolymerization in an aqueous medium in the presence of a surfactant. The surfactants used in the production of the hydrophobic acrylic resin in the present invention by emulsion polymerization include the following anionic surfactants,
There are cationic surfactants and nonionic surfactants. Examples of anionic surfactants include fatty acid salts such as sodium oleate and potassium oleate; higher alcohol sulfate esters such as sodium lauryl sulfate and ammonium lauryl sulfate; alkylbenzenes such as sodium dodecylbenzene sulfonate and sodium alkylnaphthalene sulfonate. Sulfonates and alkylnaphthalene sulfonates; naphthalene sulfonic acid formalin condensates; dialkyl sulfosuccinates; dialkyl phosphate salts; polyoxyethylene sulfates such as sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate, etc. There are ate salts, etc. Examples of cationic surfactants include ethanolamines; amine salts such as laurylamine acetate, triethanolamine monostearate formate, stearamide ethyl diethylamine acetate; lauryl trimethylammonium chloride, stearyl trimethylammonium chloride, dilauryl; dimel ammonium chloride,
distearyldimethylammonium chloride,
Examples include quaternary ammonium salts such as lauryldimethylbenzylammonium chloride and stearyldimethylbenzylammonium chloride. Examples of nonionic surfactants include polyoxyethylene higher alcohol ethers such as polyoxyethylene lauryl alcohol, polyoxyethylene lauryl ether, and polyoxyethylene oleyl ether; polyoxyethylene octylphenol, polyoxytethylene nonylphenol, etc. polyoxyethylene alkylaryl ethers; polyoxyethylene acyl esters such as polyethylene glycol monostearate; polypropylene glycol ethylene oxide adducts; polyoxyethylene such as polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan monostearate These include sorbitan fatty acid esters; sugar esters; cellulose ethers, etc. These may be used alone or in combination, but there are restrictions depending on the type of inorganic substance to be blended. That is, combinations of silica sol and cationic surfactant, which are generally negatively charged in aqueous solution, and alumina sol, which is generally positively charged in aqueous solution, and anionic surfactant should be avoided. These combinations tend to cause gelation of the sol and agglomeration/separation of the antifogging agent composition, making application difficult. These surfactants can be used in an amount of 0.1 to 10% by weight based on the total amount of monomers and ingredients. If it exceeds 10% by weight, it is not preferable because it reduces the water resistance of the dried coating film. Examples of the polymerization initiator used in the production of the hydrophobic alkaline resin of the present invention include persulfates such as ammonium persulfate and potassium persulfate; organic peroxides such as acetyl peroxide and benzoyl persulfide. It will be done. These can be used in an amount of 0.1 to 10% by weight based on the total amount of monomers charged. In the polymerization method for obtaining the hydrophobic acrylic resin of the present invention, the monomer may be introduced in a batch manner or in a continuous feeding manner. Alternatively, a method may be adopted in which a portion is first polymerized and then the remaining portion is continuously fed. Although the monomers to be continuously fed may be fed as they are, it is extremely preferable to feed the monomers as a monomer dispersion using water and a surfactant. As the aqueous emulsion of the hydrophobic alkaline resin which is a component of the antifogging composition used in the present invention, an aqueous emulsion obtained by the above-mentioned emulsion polymerization can be used as it is, or This product may be further diluted by adding a liquid dispersion medium as described below, or the polymer produced by the emulsion polymerization as described above may be collected separately and redispersed in a liquid dispersion medium to form an aqueous solution. An emulsion may also be used. The hydrophobic acrylic resin used in the present invention must have a glass transition temperature (Tg) within the range of 35 to 80°C. Such Tg resin is
It can be obtained by selecting the type and amount (compounding amount) of the monomers used. However, if the Tg of the acrylic resin used exceeds 80°C, it is difficult to obtain a transparent and uniform coating film. In addition, when the Tg is less than 35°C, the inorganic colloid particles tend to aggregate several times and become non-uniformly dispersed, and the inorganic colloid particles are not sufficiently fixed to the coating substrate, so the inorganic colloid particles gradually increase over time. may fall off the surface of the base material, impairing its anti-fog performance. The inorganic colloidal sol, which is an active ingredient of the antifogging agent composition used in the present invention, functions to impart hydrophilicity to the surface of a hydrophobic vinyl chloride resin film by applying it to the surface of the film. Examples of inorganic colloidal sols include silica,
Examples include aqueous sols in which inorganic aqueous colloidal particles such as alumina, water-insoluble lithium silicate, iron hydroxide, tin hydroxide, titanium oxide, barium sulfate, etc. are dispersed in water or a hydrophilic medium by various methods. Among them, silica gel and alumina sol are preferred. These may be used alone or in combination. The inorganic colloidal sol used preferably has an average particle size of 5 to 100 mμ.
Further, two or more types of colloidal sols having different average particle diameters may be used in combination. Average particle size is 100
If it exceeds mμ, the coating film becomes white and devitrified, which is not preferable. Further, when it is less than 5 mμ, the inorganic colloidal sol lacks stability, which is not preferable. The inorganic colloidal sol preferably has a solid content weight ratio of 0.5 to 4 based on the acrylic resin. If it is less than 0.5, sufficient anti-fog effect cannot be achieved. If it exceeds 4, not only will the anti-fog effect not improve in proportion to the amount, but if the film is transparent, the coating film formed after application will become cloudy and the light transmittance will decrease, which is undesirable. . Furthermore, the coating film tends to become rough and brittle. When a crosslinking agent is further added to the antifogging agent composition used in the present invention, water resistance is further improved. That is, this crosslinking agent allows acrylic resins to crosslink with each other, thereby improving water resistance. Crosslinking agents used for this purpose include phenolic resin membranes, amino resins, amine compounds,
Examples include aziridine compounds, azo compounds, isocyanate compounds, epoxy compounds, and silane compounds, with amine compounds, aziridine compounds, and epoxy compounds being particularly preferred. The above amine compounds include aliphatic polyamines such as diethylenetriamine, triethylenepentamine, and hexamethylene diamine; alicyclic amines such as 3,3'-dimethyl 4,4'-diaminodicyclohexylmethane and isophorone diamine;
Aromatic amines such as 4'-diaminediphenylmethane and m-phenylenediamine are used. The above aziridine compounds include tris-2,4,6-(1-aziridinyl)-1,3,
5-triazine, trimethylolpropane-tri-β-aziridinylpropionate, tris[1-(2-methyl)aziridinyl]phosphine oxide, hexa[1-(2-methyl)-aziridinyl]triphosphatriazine, etc. is used. As epoxy compounds, bisphenol A
or the reaction product of bisphenol F and epichlorohydrin, the epoxated Navolac resin produced by the reaction of epichlorohydrin with the resin reaction product of phenol (or substituted phenol) and formaldehyde, epichlorohydrin and resin group polyhydric alcohols, e.g. glycerol, 1,
4-butanediol, poly(oxypropylene)
Resin-like reaction products produced from glycol or similar polyhydric alcohol components and resins obtained by epoxidation with peracetic acid are used. For epoxy compounds, it is preferable to further use tertiary amines or quaternary ammonium salts as a catalyst. These crosslinking agents can be used in an amount of 0.1 to 30% by weight based on the solid content of the acrylic resin. In particular, a range of 0.5 to 10% by weight is preferred. The liquid dispersion medium added to the antifogging composition used in the present invention includes water-containing hydrophilic or water-miscible solvents, such as water; monohydric alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; ; polyhydric alcohols such as ethene glycol, diethylene glycol, and glycerin; cyclic alcohols such as benzyl alcohol; cellosolve acetates; and ketones. These may be used alone or in combination, but the dispersion stability of the antifogging agent composition used in the present invention, the wettability after coating on the film surface, the difficulty of removing the liquid dispersion medium, and the economic efficiency should be taken into consideration. It is preferable to decide accordingly. The antifogging agent composition used in the present invention may further contain conventional additives such as antifoaming agents, surfactants, plasticizers, film forming aids, thickeners, pigments, and pigment dispersants, as necessary. Can be mixed. The antifogging agent composition used in the present invention can be applied to the surface of a vinyl chloride resin film, and the liquid dispersion medium can be volatilized by forced drying or natural drying. As a method of forced drying, a hot air drying method, an infrared radiation method, etc. can be adopted. The heating temperature during forced drying is determined by the applied antifog composition, but is usually in the range of 50 to 250°C, preferably in the range of 70 to 200°C. The antifogging agent composition used in the present invention can be applied to the film surface by any known method such as roll coating, dip coating, brush coating, spray coating, bar coating, knife coating, etc. Good too. After applying the antifogging agent composition to the surface of the film and drying and volatilizing the liquid dispersion medium, the amount of solid matter deposited is usually 0.01 to 10 g/m ² , preferably 0.1 to 5 g/m 2 .
g/m ² range. If the adhesion between the film surface and the coating derived from the antifogging agent composition used in the present invention is insufficient, the film surface may be subjected to plasma treatment before applying the antifogging agent composition, or The surface of the film may be modified by a method such as corona discharge treatment. If the thickness of the agricultural soft vinyl chloride resin film according to the present invention is too thin, the strength will be insufficient, so it is not preferable; ), etc., so it is usually 0.03 to 0.3
The range is preferably 0.05 to 0.2 mm. The agricultural soft vinyl chloride resin film according to the present invention may be transparent, satin finish, or semi-matte finish,
It can be used to cover greenhouses, tunnels, etc., and can also be used for mulching, bagging, etc. (Effects of the invention) The present invention has the following particularly remarkable effects,
The industrial value is extremely large. (1) The agricultural soft vinyl chloride resin film according to the present invention has extremely excellent water resistance because it has a coating made of an antifogging agent containing a hydrophobic acrylic resin. (2) The agricultural soft vinyl chloride resin film according to the present invention has a coating film made of an antifogging agent containing an inorganic colloidal sol, and therefore has excellent non-adhesion, surface hardness, and water resistance. (3) The agricultural soft vinyl chloride resin film according to the present invention has an extremely excellent antifogging coating consisting of an acrylic resin of a specific composition with a glass transition temperature in the range of 35 to 30°C and an inorganic colloidal sol. It exhibits antifogging properties, and exhibits stable antifogging properties even under high temperature and high humidity conditions. Further, the vinyl chloride resin film as the base material contains an ultraviolet absorber and an organic phosphate ester, so that the antifogging performance of the antifogging coating film of the present invention is maintained for a long period of time. (Examples) Hereinafter, the present invention will be explained in detail based on Examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. Examples 1 to 8, Comparative Examples 1 to 9 (1) Preparation of base film Polyvinyl chloride (=1400) 100 parts by weight Dioctyl phthalate 45 Epoxy resin (trade name "EP-828", manufactured by Ciel Chemical) 1 Barium - Zinc-based composite stabilizer 1.5 〃 Barium stearate 0.2 〃 Zinc stearate 0.4 〃 Sorbitan monostearate 1.5 〃 Ethylene bisstearamide 0.1 〃 The basic composition is, in addition to this, the ultraviolet absorber shown in Table 1 below, Organic phosphate esters were blended in the proportions shown in the same table. After stirring and mixing each formulation for 10 minutes using a super mixer, the mixture was mixed for 7 minutes on a roll heated to 165°C.
After kneading for a minute, a film with a thickness of 0.1 mm was produced using an L-type calender. (2) Preparation of antifogging composition A four-necked flask was charged with 2 parts by weight of polyoxyethylene lauryl ether and 80 parts by weight of water, heated to 60°C under a stream of nitrogen gas, and 0.5 parts by weight of ammonium persulfate was added thereto. Add and then add the first
100 parts by weight of a mixture of each monomer shown in the table was added dropwise over 3 hours. The reaction temperature at this time is
The temperature was maintained in the range of 60 to 70°C, and even after the completion of the dropwise addition, the temperature was maintained in the same range for 2 hours, and then cooled and neutralized with aqueous ammonia to obtain an acrylic resin emulsion. The glass transition temperature of each resin was as shown in Table 1. Various antifogging agent compositions were prepared by blending the acrylic resin emulsion thus obtained with inorganic colloidal sols and others in the types and amounts shown in Table 1. However, as a comparative example, an antifogging agent composition containing no inorganic colloidal sol or acrylic resin was also prepared. (3) Formation of a coating film using an antifogging agent composition The various antifogging agent compositions obtained in (2) are coated on one side of the vinyl chloride resin film obtained in (1) by bar coating, after drying. The coating amount is as solid content.
It was applied at a concentration of 0.5 g/m ³ and left in hot air at 90° C. for 1 minute to scatter the solvent. (4) Evaluation of vinyl chloride resin film The vinyl chloride resin film obtained in (3) was evaluated for various properties using the methods described below. Adhesion of Paint Film Cellophane tape was adhered to the surface of each film on which the paint film was formed, and when the cellophane tape was peeled off, the peeling status of the paint film was observed with the naked eye. The results are shown in Table 1. This evaluation criteria is
It is as follows. ○...The paint film did not peel off at all and remained completely. ○ _x : 2/3 or more of the paint film remains without peeling off. △……2/3 or more of the paint film has peeled off. ×...The paint film has completely peeled off. Each film was cut into pieces of 5 cm wide and 15 cm long, and folded back alternately at 2 cm intervals in a direction perpendicular to the length. In this state, a load of 2 kg was applied from above and the sample was left in a constant temperature bath maintained at 15° C. for 24 hours. Then, take the load,
The folds of the film were stretched out and the appearance of the film was observed with the naked eye. The results are shown in Table 1. The evaluation criteria for this test are as follows. ○...No change is observed in the film at the crease. ○ _x : Slight cracks are observed in the coating at the creases. △...Slight cracks are observed in the coating at the creases. ×: Scratching moths are significantly observed on the film at the crease. Anti-fog property test Each film was installed in a small tunnel (1 m wide, 4 m deep,
The anti-fogging properties were periodically evaluated visually with the naked eye. The evaluation criteria are as follows. ◎...Water adheres in a thin film and no water droplets are observed. ○...Water is attached in a thin film, but slightly large water droplets are observed. ○ _x : Water is attached in a thin film, but large water droplets are observed to be attached in some areas. △...Situation in which small water droplets are observed to be attached in some areas. ×...Small water droplets are observed on the entire inner surface of the film.

【table】

【table】

[Table] The following is clear from Table 1. (1) The agricultural soft vinyl chloride resin film of the present invention has excellent antifogging properties, particularly long lasting antifogging properties, and even after 24 months, it maintains the good antifogging properties almost at the initial stage of expansion. (2) Even if the antifogging agent composition of the present invention is applied, if the vinyl chloride resin film serving as the base film does not simultaneously contain an ultraviolet absorber and an organic phosphate ester, the antifogging durability will be poor. Comparative Examples 1, 2, 8 (3) When the glass transition temperature of the acrylic resin contained in the antifogging agent composition is less than 35°C, the antifogging durability is poor. (Comparative Example 3). On the other hand, if the glass transition temperature is 80°C or higher, the adhesion of the anti-fog coating to the flexible film is poor and the anti-fog durability is also poor. (Comparative Example 4). (4) The (meth)acrylic acid monomer component constituting the hydrophobic acrylic resin contained in each antifogging composition
If the amount of other α,β-ethylenically unsaturated monomer components that can be copolymerized with this monomer exceeds 40% by weight, the adhesion of the anti-fog coating to the film will be poor and the anti-fog The durability is also poor (Comparative Example 5). (5) If either one of the two components constituting the antifogging agent composition, ie, the acrylic resin and the inorganic colloidal sol, is missing, the antifogging properties will be very poor.
(Comparative Examples 6 and 7) Comparative Example 10 In this comparative example, a coating film made of acrylic resin was first formed on the surface of the vinyl chloride resin film on which antifogging properties were to be imparted, and then colloidal silica was applied on the surface of the vinyl chloride resin film. An anti-fog film with a coating film formed thereon was manufactured and its performance was evaluated. That is, the following composition (hereinafter, parts by weight are simply referred to as parts) Methyl methacrylate 60 parts Butyl methacrylate 30 parts Trimethylaminoethyl methacrylate hydrochloride
10 parts benzoyl peroxide 0.5 parts isopropanol 300 parts were charged into a flask and reacted at 80° C. for 7 hours under a nitrogen atmosphere. Isopropanol was added to the obtained product to obtain acrylic resin paint A having a solid content of 13% by weight. On the other hand, the following composition: 0.5 parts of colloidal silica with a particle size of 10 to 14 μm, 0.5 parts of colloidal silica with a particle size of 70 to 90 μm, 0.1 part of water-soluble cellulose ether, and 100 parts of water are stirred to uniformly disperse the colloidal silica.
Antifog composition B containing colloidal silica as an active ingredient was obtained. The same vinyl chloride resin film (blended with an ultraviolet absorber and an organic phosphate ester) used in Example 1 of the present invention was first coated with the acrylic resin paint A using a bar coating method, and then heated with hot air. Dry at 90℃) and reduce the solid content to 0.25 after drying.
g/ ^m2 . Next, the above-mentioned antifogging agent composition B was applied to the coated surface using a bar coating method, and dried with hot air (90°C), so that the amount of solid content after drying was 0.25 g/m ² .
The performance of the obtained film was evaluated using the same evaluation method as shown in Table 1 above, and the results are shown in Table 2 below. Comparative Example 11 In this comparative example, a coating film of an acrylic anionic polymer electrolyte shown below was first formed on the antifogging surface of a vinyl chloride resin film, and then a coating film made of alumina sol was formed on the film. An anti-fog film was manufactured and its performance was evaluated. That is, the following composition: 60 parts of methyl methacrylate, 30 parts of butyl methacrylate, 10 parts of methacrylic acid, 0.5 parts of benzoyl peroxide, and 300 parts of isopropanol were charged into a flask and reacted at a temperature of 80° C. for 7 hours under a nitrogen atmosphere. After the reaction was completed, sodium hydroxide was added in an amount to neutralize half of the methacrylic acid component to electrolyte the resulting polymer. Isopropanol was added to this to obtain an acrylic anionic polymer electrolyte C having a solid content of 13% by weight. On the other hand, 1 part of alumina sol was uniformly dispersed in 100 parts of water to obtain an antifogging agent composition D containing alumina sol as an active ingredient. First, the above-mentioned polymer electrolyte C was coated on one surface of the same vinyl chloride resin film (blended with an ultraviolet absorber and an organic phosphate ester) as used in Example 1 of the present invention using a barcode method, and then the film was heated at 90°C. The solid content after drying was 0.25 g/m ² . Next, the above-mentioned antifogging composition D was applied onto the coating surface by a bar coating method, and this was dried with hot air at 90°C, so that the solid content after drying was 0.25 g/m ² . The performance of the film thus obtained was evaluated in the same manner as in Table 1 above. Second result
Shown in the table.

【table】

[Table] When an acrylic resin coating is first formed and an inorganic colloidal sol coating is formed on top of it as described above, it can be said that the adhesion and durability of the anti-fogging function are sufficient compared to that of the present invention. do not have.

Claims (1)

[Scope of Claims] 1. On one or both sides of a soft vinyl chloride resin film containing an ultraviolet absorber and an organic phosphate ester, (a) 60 to 100% by weight of a monomer consisting of an alkyl ester of acrylic acid or methacrylic acid. or a mixed monomer of alkyl esters of acrylic acid or methacrylic acid and alkenylbenzenes, and other α,β-ethylenically unsaturated monomers that can be copolymerized with 0 to 40% by weight of the above monomers. (b) one or more aqueous emulsions of hydrophobic acrylic resins having a glass transition temperature in the range of 35 to 80°C, obtained by emulsion polymerization with monomers; and (b) one or two inorganic colloidal sols. more than species (a)
and (b) coating an antifogging agent composition containing a mixture of two components or an antifogging agent composition containing a mixture of the two components (a) and (b) above, a crosslinking agent, and/or a liquid dispersion medium. Soft vinyl chloride resin film for agricultural use.