KR19990063334A - Resin film - Google Patents

Abstract

A radiation blocker (A agent) having a refractive index ranging from 1.47 to 1.65, a radiation blocker (B agent) having a different chemical composition from agent A, and a thermoplastic resin, and the total amount of the radiation blocker is 0.5 parts by weight per 100 parts by weight of the thermoplastic resin. The above resin film is a resin film having a radiation transmittance index of 35 or less and a total light transmittance of 80% or more at 23 ° C. This resin film is excellent in heat retention and transparency.

Description

Resin film

The present invention relates to a resin film that effectively blocks radiation while transmitting visible light well.

Conventionally, as an agricultural film used for agricultural houses or tunnels in facility horticulture, etc., since visible light is important in crop growth, an olefin resin film or a polyvinyl chloride film such as a polyethylene film or an ethylene-vinyl acetate copolymer film The film which is excellent in transparency of visible light, such as a polyethylene terephthalate film, a polymethyl methacrylate film, a polycarbonate film, and a fluororesin film, is used. Moreover, what is important in crop growth is maintaining the temperature in facilities, such as a house, high. Many attempts have been made to prevent radiation transmission from the ground in the facility at night to the sky, especially to prevent nighttime temperature drops.

For example, a phosphate compound, silicon oxide, anhydrous aluminosilicate, as described in each publication, such as Unexamined-Japanese-Patent No. 52-105953, Unexamined-Japanese-Patent No. 4-11107, and Unexamined-Japanese-Patent No. 57-34871. In addition, inorganic resins such as dehydrated kaolinite, aluminum, silicates, zeolites, hydrotalcites, or organic compounds such as acetal resins are added to improve resin insulation.

However, when various inorganic compounds are added to the film for the purpose of suppressing radiation transmission, there is a problem that the transparency of the film is lowered.

The present invention is to provide a resin film that effectively blocks visible radiation while transmitting well visible light.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, when it used together with other radiation shielding agents rather than using a specific radiation shielding agent alone, the present inventors discovered that heat insulation and transparency improved.

That is, the present invention comprises a radiation blocker (A agent) having a refractive index in the range of 1.47 to 1.65, a radiation blocker (B agent) having a chemical composition different from that of A agent, and a thermoplastic resin, wherein the total amount of the radiation blocker is thermoplastic resin 100 It is a resin film which is 0.5 weight part or more per weight part, and is a resin film whose radiation transmittance index at 23 degreeC of this film is 35 or less, and total light transmittance is 80% or more.

The resin film of this invention contains two or more types of radiation shielding agents. Radiation is an infrared ray radiated from a black body (for example, the ground) and has a wavelength of 2 to 25 µm, and a radiation blocker has a property of absorbing or reflecting radiation.

As a radiation shielding agent, an infrared absorber and an infrared reflector can be illustrated, for example. The infrared reflector is not particularly limited as long as it reflects infrared rays of at least one of the wavelength ranges.

The radiation shielding agent (made in A) used by this invention will not be specifically limited if the refractive index measured by the method of JISK0062 exists in the range of 1.47-1.65. The refractive index of the agent A is preferably 1.47 to 1.54, and more preferably 1.49 to 1.53. A One type may be sufficient as me and two or more types may be sufficient as it. In addition, about the radiation shielding agent (B agent) which is used together with agent A and whose chemical composition differs from agent A, the refractive index is not specifically limited. Especially in the case of the resin film used for the use which requires transparency, the refractive index of the agent B measured by the method described in JIS K0062 is preferably in the range of 1.47 to 1.65, more preferably in the range of 1.47 to 1.54, It is especially preferable to exist in the range of 1.49-1.53. One type of B agent may be sufficient and two or more types may be sufficient as it.

The ratio (na / nr) of the refractive index (na) of the radiation blocking agent (A agent) to the refractive index (nr) of the thermoplastic resin, and the refractive index (nb) of the radiation blocking agent (B agent) to the refractive index (nr) of the thermoplastic resin Since ratio (nb / nr) is all closer to 1, it exists in the tendency which was excellent in transparency of a resin film, and is preferable. Although the range of these ratios is not necessarily limited, Usually, the range of 0.95-1.05 is preferable and the range of 0.98-1.02 is more preferable.

Examples of the radiation shielding agent used in the present invention include complex hydroxides such as hydrotalcite compounds and lithium aluminum complex hydroxides, silicates such as aluminum silicate, aluminosilicates such as sodium aluminosilicate, basic aluminum carbonate, And other composite oxides.

Hydrotalcite compound is a compound represented by the following formula (1)

M ²⁺ _1-X Al _X (OH) ₂ (A ₁ ^n- ) _{x /} nmH ₂ O

(Wherein M ²⁺ is a divalent metal ion, A ₁ ⁿ⁻ is an n-valent anion, and x and m satisfy the conditions of 0 <x <0.5 and 0 ≦ m ≦ 2).) . Examples of M ²⁺ include Mg ²⁺ , Ca ²⁺ , Zn ^2+, and the like. n-valent anion is not particularly limited, for example, ^{Cl -, Br -, I -} , NO 3 -, ClO 4 -, SO 4 2-, CO 3 2-, SiO 3 2-, HPO 4 3-, HBO _{^{4 3-, PO 4 3-, Fe}} (CN) 6 3-, Fe (CN) 6 4-, CH 3 COO -, C 6 H 4 (OH) COO -, (COO) 2 2-, terephthalate ion, Anions, such as naphthalene sulfonate, and the polysilicate ion and polyphosphate ion of Unexamined-Japanese-Patent No. 8-217912 are mentioned. Specifically, synthetic hydrotalcite, such as natural hydrotalcite and DHT-4A (brand name, Kyowa Chemical Co., Ltd. product) etc. are mentioned, for example. It is preferable that n in Formula (1) is 1 or more and 4 or less.

Examples of the lithium aluminum composite hydroxide include the following general formula (II) disclosed in Japanese Unexamined Patent Application Publication No. Hei 5-179052:

_{^{Li + (Al 3+) 2 (}} OH -) 6 (A 2 n-) 1 / n · mH 2 O

And a compound represented by (wherein A ₂ ^{n −} is an n-valent anion and m satisfies the condition of 0 ≦ m ≦ 3). The n-valent anion is not particularly limited, and examples thereof include the same anion as A ₁ ^n- in Formula (I). It is preferable that n in Formula (II) is 1 or more and 4 or less.

Examples of the complex hydroxides other than the above two kinds include complex hydroxides having a hydroxyl group, including Li and Al, and at least one element selected from alkaline earth metals, transition metals, Zn and Si. Among the alkaline earth metals, magnesium and calcium are preferable. Moreover, in transition metal, bivalent or trivalent iron, cobalt, nickel, and manganese are preferable, and iron is more preferable especially. The molar ratio (Al / Li) of Al and Li is usually 1.5 / 1 to 2.5 / 1, preferably 1.8 / 1 to 2.5 / 1.

The molar ratio (a) of the element selected from the group consisting of alkali earth metals, transition metals, Zn and Si is usually 0 <a <1.5 with respect to 1 mol of Li elements, preferably 0.1≤a≤1.4, more preferably Preferably 0.2 ≦ a ≦ 1.2. Anionic moieties other than the hydroxyl groups of such composite hydroxides are, for example, polysilicate ions such as phyllosilicate ions, cyclosilicate ions, isosilicate ions, pyrosilicate ions, and tectic silicate ions, carbonate ions, halogenated ions, sulfate ions and sulfite ions. , Inorganic acid ions such as nitrate ion, nitrite ion, phosphate ion, phosphite ion, hypophosphite ion, polyphosphate ion, aluminate ion, silicate ion, perchlorate ion, borate ion, Fe (CN) ₆ ^3- , Fe (CN) ₆ is an anionic transition metal complex of the ^4-, etc. include, acetate ion, benzoate ion, formate ion, terephthalate ion, organic acid ion such as an alkylsulfonic acid ions and the like. Among these, carbonate ions, halide ions, sulfate ions, phosphate ions, polyphosphate ions, silicate ions, polysilicate ions and perchlorate ions are preferred, and carbonate ions, polyphosphate ions, silicate ions and polysilicate ions are particularly preferred. .

Specific examples of such a composite hydroxide include Al, Li and Mg, Al / Li / Mg = about 2.3 / 1 / 0.28 (molar ratio), a composite hydroxide (trade name: LMA, manufactured by Fuji Chemical Industries, Ltd.), Al, And composite hydroxides (trade name: Fujilane LS, manufactured by Fuji Chemical Industries, Ltd.) containing Li and Si and Al / Li / Si = about 2/1 / 1.2 (molar ratio).

Formula 3 disclosed in WO97 / 00828:

_{^{[(1-x Li + (}} ) M 2+ x) (Al 3+) 2 (OH -) 6] 2 (Si y O (2y + 1) 2-) (1 + x) · mH 2 O

Wherein, M ²⁺ is a divalent metal ion, and m, x and y satisfy the conditions of 0 ≦ m <5, 0 ≦ x <1, 2 ≦ y ≦ 4. [Formula 4] disclosed in Patent Publication No. Hei 8-217912:

_{^{[(Li + (1-x}} ) M 2+ x) (Al 3+) 2 (OH -) 6] 2 (A n-) 2 (1 + x) / n · mH 2 O

In the formula, M ²⁺ is a divalent metal ion, A ^n- is an n-valent anion, and m and x satisfy the conditions of 0 ≦ m <5 and 0.01 ≦ x <1. It is a preferable example of a composite hydroxide. As M <^2+> in general formula (III) and (IV), Mg2 ⁺ , Ca2 ⁺ , Zn2 ⁺ etc. are illustrated. N in the formula (IV) is preferably 1 or more and 4 or less.

As a basic aluminum carbonate salt, it consists of 1 or more types of cations other than aluminum ion, carbonate ion, and aluminum ion. Examples of the cation of the aluminum ion include alkali metal ions, alkaline earth metal ions, ammonium ions, transition metal ions, and the like. Among them, sodium ions, potassium ions and ammonium ions are preferable. As an example of such a basic aluminum carbonate salt, the salt of Unexamined-Japanese-Patent No. 9-279131, and the salt illustrated by following documents (1) and (2) are mentioned. Specifically, for example, sodium aluminum carbonate (Na ₂ O.Al ₂ O ₃ .2CO ₃ .nH ₂ O (n> 0)), potassium aluminum carbonate (K ₂ O.Al ₂ O ₃ .2CO ₃ .nH _2. O (n> 0)), and the like (see Literature (1) Comprehensive inorganic chemistry vol 2. 1045 page 1973 Pergamon Press Ltd., Literature (2): A comprehensive treatise on inorganic and theoretical chemistry vol) 5. Longman, Green and Co Ltd, published in 1960, pages 358-359.

Among these various radiation blockers, silicon oxide is preferably used as the B agent in that it can exert a synergistic radiation shielding effect in combination with the A agent and is inexpensive.

When the inorganic compound containing a high concentration of alkali metal is contained in the composition, it is easy to express basicity in the resin composition, and the inorganic compound, which is preferable as a radiation blocker, is likely to cause deterioration or discoloration of the resin film of the present invention. Therefore, it is preferable that the alkali metal content rate of such an inorganic compound is 3 weight% or less, Furthermore, 2.5 weight% or less, especially 2 weight% or less.

5 micrometers or less are preferable, as for the average particle diameter of the said radiation shielding agent, 0.05-3 micrometers is more preferable, 0.1-1 micrometer is especially preferable.

In order to improve the dispersibility in resin or a film, a radiation blocking agent may be surface-treated with a dispersing agent. Examples of the dispersant include high-fatty acids such as stearic acid, palmitic acid and lauric acid, high-fat fatty acid calcium salts, zinc acid, magnesium salts, barium salts and sodium salts, various phosphate esters, silane coupling agents, and aluminum coupling agents. , Zirconium-based coupling agents, various waxes and the like can be exemplified. The surface treatment method may be any method in which the dispersant is uniformly adhered to the radiation blocker surface. Examples thereof include a method in which the radiation blocker is slurried in a suitable solvent, and the slurry and the dispersant are mixed and stirred.

The total compounding quantity of a radiation shielding agent is 0.5 weight part or more with respect to 100 weight part of thermoplastic resins, Preferably it is 1-30 weight part, More preferably, it is 2-15 weight part. Although 2 or more types of radiation shielding agents are used in this invention, these fractions are not specifically limited. The weight ratio of each radiation blocker to the sum of the weight amounts of the radiation blocker, that is, (weight of one radiation blocker) / (total weight amount of the radiation blocker) is preferably in the range of 0.05 to 0.95, preferably in the range of 0.1 to 0.9. Is more preferable, and the range of 0.2-0.8 is especially preferable.

When the compounding weight of a radiation shielding agent (A agent) is set to A, and the compounding weight of a radiation shielding agent (B agent) is set to B, it is preferable that following formula is satisfied. If this condition is met, the synergistic radiation shielding effect is particularly pronounced.

0.3 <A / (A + B) <0.7

The radiation transmittance index at 23 ° C. of the resin film of the present invention is 35 or less, and the total light transmittance is 80% or more. The radiation transmittance index at 23 ° C. is a measure of the ability to block the transmission of radiation and can be obtained by a measuring method described later. This is also a measure of heat retention when the resin film is used as an agricultural coating film. The smaller this value, the better the heat retention of the resin film. When the resin film of the present invention has a radiation transmittance index of 35 or less at 35 ° C., excellent heat retention can be achieved. Also, when the resin film is used as a coating material for a heating house, heating costs can be reduced and economic efficiency can be improved. have. The radiation transmittance index is preferably closer to zero, more preferably 20 or less, and particularly preferably 15 or less.

The total light transmittance is one measure of transparency of the film and can be measured by a method described later. The greater the total light transmittance, the more transparent the resin film and the visible light. If the total light transmittance is less than 80%, the transmission of visible light is not sufficient.

Although the thermoplastic resin used for this invention is not specifically limited, For example, polyolefin resin, such as polyethylene and an ethylene / vinyl acetate copolymer, soft polyvinyl chloride, polyethylene terephthalate, polymethyl methacrylate, a polycarbonate, a fluororesin, etc. The thermoplastic resin which is excellent in the transparency of visible light of is used.

Especially, polyolefin resin is used preferably. Specific examples of the polyolefin resin include homopolymers of α-olefins such as polyethylene and polypropylene, or ethylene / propylene copolymers, ethylene / butene-1 copolymers, ethylene / 4-methyl-1-pentene copolymers, and ethylene / Ethylene / α-olefin copolymers such as hexene-1 copolymer and ethylene / octene-1 copolymer, for example ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / methyl methacrylate copolymer, ethylene / acetic acid The copolymer with the heterogeneous monomer which has alpha-olefins, such as a vinyl / methyl methacrylate copolymer and an ionomer resin as a main component, is mentioned. In the case where the resin film of the present invention is used for agricultural coating films, polyethylene, ethylene / α-olefin copolymers and ethylene / vinyl acetate copolymers having a vinyl acetate content of 30% by weight or less are particularly preferable in consideration of transparency, weather resistance and price. Do.

Although the manufacturing method of the said polyolefin resin is not specifically limited, For example, as a method of obtaining an ethylene / alpha-olefin copolymer, ethylene and C3-C18 alpha-olefin are used as transition metal complex catalysts, such as palladium and nickel, or a metal. The so-called single-site catalysts, such as a sensitized catalyst, are mentioned, and the method of superposing | polymerizing in a gaseous phase / solid state, a liquid phase / solid state, or a homogeneous liquid phase in presence or absence of a solvent is mentioned. The polymerization temperature is usually 30 ° C. to 300 ° C., and the polymerization pressure is usually almost atmospheric pressure to 3000 kg / cm 2. For example, the metallocene catalyst components described in JP-A-69724, JP-A-6-136195, JP-A-6-136196, JP-A-6-207057, and the like. In the presence of a so-called metallocene-based olefin polymerization catalyst to contain, an ethylene / α-olefin copolymer can be produced by copolymerizing ethylene with an α-olefin having 3 to 18 carbon atoms.

The resin film of this invention may contain a hindered amine compound. Examples of the hindered amine compound include those having the structural formula described in Japanese Patent Application Laid-Open No. Hei 8-73667. Specific examples include TINUVIN 622LD, TINUVIN 123, and CHIMASSORB 944LD (above, manufactured by Chiba Specialty Chemicals Co., Ltd.), HOSTAVIN N 30, VP SANDUVOR PR-31 (above, manufactured by Clariant KK), CYASORB UV 3526 (manufactured by Cytec Industies Inc.), and the like. As a hindered amine compound containing stabilizer, the composition (brand name TINUVIN 492, TINUVIN 494, product made by Chiba Specialty Chemicals) of Unexamined-Japanese-Patent No. 63-286448 is illustrated. These hindered amine compounds may be used independently or 2 or more types may be used together.

When using a hindered amine compound, the quantity is 0.02 weight% or more in a resin film from a viewpoint of a weather resistance improvement effect, and is 5 weight% or less from a viewpoint of suppressing a blooming phenomenon. Preferably it is 0.1-2 weight%.

The resin film of this invention may contain a ultraviolet absorber. Such ultraviolet absorbers include commercially available ultraviolet absorbers such as benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers, benzoate ultraviolet absorbers, and cyanoacrylate ultraviolet absorbers. An inorganic ultraviolet absorber may contain metal oxides, such as a cerium oxide or a titanium oxide, For example, the ultraviolet absorber marketed by Nihon Mukai Chemical Co., Ltd. make and a brand name: Serigard can be used. In addition, these ultraviolet absorbers may be used independently or may use 2 or more types together. When using a ultraviolet absorber, 0.01-3 weight% is preferable in a resin film from a viewpoint of a weather resistance improvement effect and blooming suppression, and its 0.05-1 weight% is more preferable.

The resin film of this invention may contain polyacetal, polyvinyl alcohol, its derivative (s), an ethylene-vinyl alcohol copolymer, etc. as an organic type infrared absorber, and these may be used independently or may be used together 2 or more types.

In addition, the resin film of this invention can contain various antifouling agents. Examples of the antifoaming agent include a fluorine compound (particularly a fluorine-based surfactant) having a perfluoroalkyl group, a ω-hydrofluoroalkyl group and the like, and a silicon compound (particularly a silicone-based surfactant) having an alkylsiloxane group. have. Specific examples of the fluorine-based surfactant include DS-403, DS-406, and DS-401 (all manufactured by Daikin Kogyo Co., Ltd.), and trade name SH-3746 (Toray Dow Corning Silicon ( Co., Ltd.) is mentioned.

In the case of using a waterproofing agent, the amount is generally 0.01 to 4% by weight, preferably 0.02 to 2% by weight, more preferably 0.05 to 0.5% by weight in the resin film.

The resin film of the present invention may contain various antifog agents. Such antifog agents are solid and liquid at room temperature. Examples of the solid antifog agents include nonionic surfactants, for example, sorbitan fatty acid ester-based surfactants such as sorbitan monostearate, sorbitan monopalmitate, sorbitan monomontanate, glycerin monopalmitate, and glycerin monostea Glycerin fatty acid ester-based surfactants such as latex, diglycerin distearate, triglycerin monostearate, tetraglycerin dimontanate, polyethylene glycol-based surfactants such as polyethylene glycol monopalmitate and polyethylene glycol monostearate, and alkylphenols. Esters of alkylene oxide adducts, sorbitan / glycerine condensates and organic acids; Polyoxyethylene alkylamine compounds, such as polyoxyethylene (2 mol) stearylamine, polyoxyethylene (2 mol) laurylamine, and polyoxyethylene (4 mol) stearylamine, polyoxyethylene (2 mol) stearyl Amine monostearate, polyoxyethylene (2 moles) stearylamine distearate, polyoxyethylene (4 moles) stearylamine monostearate, polyoxyethylene (4 moles) stearylamine distearate, polyoxyethylene Fatty acid ester of polyoxyethylene alkylamine compounds, such as (8 mol) stearylamine monostearate, polyoxyethylene (2 mol) stearylamine monobehenate, and polyoxyethylene (2 mol) laurylamine stearate, poly Amine surfactants, such as fatty acid amide of polyoxyethylene alkylamine compounds, such as oxyethylene (2 mol) stearic acid amide, are mentioned.

As a liquid type | mold antifog, glycerol monooleate, diglycerol monooleate, diglycerin sesquioleate, tetraglycerol monooleate, hexaglycerol monooleate, hexaglycerin trioleate, tetraglycerine trioleate, for example Glycerine fatty acid esters, such as tetraglycerol monolaurate and hexaglycerol monolaurate, are also sorbitan fatty acid esters, such as sorbitan monooleate and sorbitan dioleate. In film storage, it is preferable to use a liquid antifog and a solid antifog together at room temperature from the viewpoint of suppressing the bleed out of the antifog to the film surface and film transparency.

When using an antifogging agent, the quantity is generally 0.5 to 5 weight% in the resin film, Preferably it is 1.5 to 4 weight%, More preferably, it is 2.2 to 2.8 weight%.

The resin film of the present invention may contain a near infrared ray blocker. When a resin film containing a near infrared ray shielding agent is used as a coating material for the green house, it is possible to suppress the temperature drop inside the house during the hot season. As the near-infrared blocking agent, for example, an organic compound disclosed in Japanese Patent Application Laid-Open No. H10-193522 (for example, a nitroso compound and metal complex salt thereof, a cyanine compound, a squarium compound, a thiol nickel complex salt compound, Phthalocyanine compounds, triallyl methane compounds, immonium compounds, dimonium compounds, naphthoquinone compounds, anthraquinone compounds, amino compounds, aluminum salt compounds) and inorganic And compounds such as carbon black, antimony oxide, tin oxide doped with indium oxide, metal oxides or carbides and boron compounds belonging to the 4A, 5A or 6A group of the periodic table. You may form the film containing a near-infrared blocker on the surface of the resin film of this invention. As a formation method of this film, the coating method containing a near-infrared blocker and a water-soluble resin binder is apply | coated to a resin film, and the method of drying is mentioned, for example.

The resin film of this invention can further mix | blend additives, such as weathering agents, a lubricating agent, a pigment, and a backing agent, such as a wax, antioxidant, an antistatic agent, and light stabilizers other than a hindered amine type as needed. For these additives, see Nihon Kagakujo Co., Ltd. in 1987, Tanaka et al., Polymer Additives Separation and Analysis Technology, and Kato Kogo Co., Ltd. in 1970. It is described. In addition, these additives may be used independently or may be used together 2 or more types.

The resin film of the present invention contains a radiation blocker (A agent) having a refractive index in the range of 1.47 to 1.65, and a radiation blocker (B agent) having a different chemical composition from that of the A agent. The distribution form of these radiation shielding agents in a resin film is not specifically limited. For example, when a resin film consists of a single layer, inevitably both sides of A agent and B agent are contained in the layer. On the other hand, when the resin film is a laminated film having two or more layers, these radiation blocking agents may be contained in the same resin layer, or may be contained in separate resin layers. When two or more types of radiation shielding agents are used as A agent, these radiation blocking agents may be contained in the same resin layer, and may be contained divided into two or more resin layers. The same applies to the B agent. The resin film of this invention may have the thermoplastic resin which does not contain a radiation shielding agent other than the resin layer containing a radiation blocking agent. When the resin film of this invention is a laminated film, the layer structure is not specifically limited, For example, 2 types of 2 layers, 2 types of 3 layers, 3 types of 3 layers, etc. are illustrated.

The resin film of the present invention can be produced using a resin composition obtained by mixing and kneading a resin with a predetermined amount of a radiation shielding agent and various additives, if necessary, by mixing and kneading dough. Inflation molding, extrusion T-die film molding, calendering, and the like are used for the production of the monolayer film, and coextrusion, solution coating, extrusion lamination, dry lamination, etc. are also used for the production of the laminated film. In the preparation of the resin composition, as a mixing / mixing dough, for example, a ribbon blender, a super mixer, a Banbury mixer, a single screw extruder and a twin screw extruder can be used.

It is preferable that the thickness of the resin film of this invention is 0.01 mm or more from the strength point of a film, and 0.3 mm or less is preferable from a point of coating workability of a film. More preferably, it is 0.03-0.25 mm.

The resin film may have an antifogging film on at least one surface thereof for the purpose of sustaining the antifogging property of the resin film of the present invention for a long time. As such an antifogging film, for example, a coating film of an inorganic oxide sol such as colloidal silica or alumina sol described in JP-A-49-32668, JP-A-50-11348, etc., JP-A-63- Coating films and interfaces such as inorganic oxide sol and organic compounds (surfactants, resins, etc.) described in 45432, Japanese Patent Laid-Open No. 63-45717, Japanese Patent Laid-Open No. 64-2158, and Japanese Patent Laid-Open No. 3-207643, etc. The coating film of the liquid which has an active agent as a main component, the film | membrane which has a hydrophilic resin (for example, polyvinyl alcohol, polysaccharides, polyacrylic acid, etc.) as a main component, etc. are mentioned. The method of forming these antifogging films may be a coating method or a method of laminating a previously formed antifogging film on a resin film. The antifogging film may be a single layer or two or more layers.

The resin film can be preferably used as an agricultural film, in particular, a coating film of agricultural facilities such as houses.

The resin film of the present invention is remarkably excellent in heat retention, which is one of important properties in crop cultivation, and thus can achieve a high crop growth effect. Therefore, the resin film of this invention is used suitably as a coating film of agricultural facilities, such as a greenhouse and a tunnel, and agricultural films, such as a curtain and mulching provided in these.

And the resin film of this invention can achieve 80% or more, in some cases 90% or more, and also 92% or more by total light transmittance. By also combining such high visible light transmittance, when the resin film of this invention is used as agricultural films, such as a horticulture house tunnel, curtain, etc., photosynthetic efficiency can be improved and high crop growth (harvest yield) is achieved. In addition, the HAZE value of the resin film of the present invention may be approximately 30% or less, preferably 25% or less, particularly 20% or less. In general, the smaller the HAZE value, the higher the transmittance of parallel rays. The higher the permeability of the parallel rays, the more the daylight in the houses and tunnels can be taken in to increase the temperature and temperature in the houses and tunnels. It can have a good effect on the growth of watermelon and strawberries.

The resin film of the present invention having excellent radiation shielding properties can be effectively used for window mounting films (buildings, automobiles, vehicles, ships, etc.), infrared sensor window materials, and the like.

According to the Example published next, it turns out that a high synergistic effect can be acquired by using A agent and B agent together as a radiation shielding agent. That is, the radiation shielding which is defined by the following formula using the radiation transmittance index (α) obtained by averaging from the value when each radiation shielding agent is used alone, and the radiation transmission index (β) when these radiation blocking agents are used in combination. The synergy index (ΔQ) amounts to 10% or more.

ΔQ = 100 (α-β) / α [unit%]

The higher ΔQ, the higher the radiation blocking effect. ΔQ is preferably 10% or more, more preferably 20% or more, and still more preferably 30% or more.

Example

Hereinafter, although the Example of this invention is shown, this invention is not limited to this. And the test method in an Example and a comparative example is as follows.

(1) Radiation Transmission Index

Using an infrared spectrometer (type 1640 FTIR manufactured by Perkin Elma Co., Ltd.), the radiation transmittance index is obtained by the following method, and is determined as a measure of thermal insulation.

The infrared absorption spectrum (transmission method) of a film (thickness 100 microns) is measured in the range of wave number 4000-400 cm <^-1> at the temperature of 23 degreeC, and the transmittance | permeability T ((nu))% value in wavenumber (nu) is obtained.

On the other hand, the blackbody radiation spectrum intensity | strength e ((nu)) in wave number ((nu)) is computed at 23 degreeC according to following formula 1 obtained by the Frank's law. Here, the product of the blackbody radiation spectrum intensity e (v) multiplied by the transmittance T (v) becomes the radiation transmission intensity f (v) (Equation 2).

Integrating the radiation transmission intensity f (ν) in the wave number 4000 to 400 cm ^-1 range and integrating the radiation transmission energy (F) and the blackbody radiation spectrum intensity e (ν) in the wave number range 4000 to 400 cm ^-1 As energy (E), it defines with the radiation transmittance index G = 100 * F / E. The actual integration is divided into sections at every 2 cm ^-1 interval, and each section is calculated by trapezoidal approximation and integrated. The smaller the radiation transmittance index, the better the heat retention of the film.

e (ν) = (A / λ ⁵ ) / (exp (B / (λ × T)) ^-1 } (Equation 1)

Where A = 2 π hC ² = 3.74 × 10 ^-16 (W

B = hC / k = 0.01439 (mK)

T (K) is absolute temperature. λ (cm) is the wavelength (wave number ν is the inverse of the wavelength), h is the Frank constant, C is the luminous flux, k is the Boltzmann constant, A is the first radiation constant, B is the second radiation constant.

f (ν) = e (ν) × T (ν) / 100 (Equation 2)

(2) total light transmittance and HAZE value

Measure with a digital haze meter (manufactured by Suga Tester Co., Ltd.).

Examples 1 and 2

0.2 weight% of hindered amine compound A in ethylene / vinyl acetate copolymer (19% of vinyl acetate content, the melt index 1.5g / 10min Sumitomo Chemical Co., Ltd. make) so that the total amount of materials may be 100 weight%. 0.6% by weight of the amine compound B, 0.2% by weight of the antioxidant and the radiation blocker A and the radiation blocker B in the amounts shown in Table 1 were added, and mixed and kneaded at 140 DEG C for 5 minutes using a Banbury mixer. And v) to obtain a composition pellet. Let this be the resin composition ①. Next, the hindered amine compound B 0.6% by weight in an ethylene / vinyl acetate copolymer (5% in vinyl acetate content, manufactured by Sumitomo Chemical Co., Ltd.) with a melt index of 0.5 g / 10 minutes so that the total amount of the material was 100% by weight. And 0.06 weight% of antioxidant I is added, it mixes and knead | mixes for 5 minutes at 140 degreeC using Banbury mixer, and granulates with a granulator to obtain a composition pellet. Let this be the resin composition ②. Further, 0.6 wt% of the hindered amine compound B and 0.24 wt% of the ultraviolet absorber were applied to low-density polyethylene (density 0.925 g / cm 3, melt index 1.5 g / 10 min, manufactured by Sumitomo Chemical Co., Ltd.) so that the total amount of the material was% by weight. %, 0.06% by weight of antioxidant I, 0.05% by weight of oleic acid amide, and kneaded at 140 DEG C for 5 minutes using a Banbury mixer, and then granulated with a granulator to obtain a composition pellet. Let this be the resin composition ③. The resin composition ① was made into the intermediate | middle layer, and resin compositions ② and ③ were made into the inner and outer layers, and the film of 0.1 mm of film thickness (middle layer 0.065 mm, inner and outer layers each 0.0175 mm) is produced with the inflation film forming machine, and performance is evaluated. The results are shown in Table 1 and are excellent.

In addition, the material used in the procedure is as follows.

Hindered Amine Compound A: Kimasov 944LD (manufactured by Chiba Specialty Chemicals)

Hindered Amine Compound B: Tinupin 622LD (manufactured by Chiba Specialty Chemicals)

UV absorber: Sumif 130 (manufactured by Sumitomo Chemical Co., Ltd.)

Antioxidant: Iruganox 1010 (manufactured by Chiba Specialty Chemicals)

Comparative Examples 1 and 2

Except having made content of a radiation shielding agent as described in Table 1, a film is produced by the method similar to Example 1, and these performances are evaluated. The results are inferior as shown in Table 1.

Reference Example 1

Anti-fog coating liquid A (Snowtex 30 / Kayacrylic H300 / Epichron 860 / Water / Ethanol = 4/3 / 0.1 / 75/25 weight ratio) was mixed on the surface of the temporary composition ② of Example 2. It can apply | coat and dry so that it may become about 1 g / m <2> of solid content, and a film can be obtained. These are films excellent in weather resistance, antifogging property, transparency, etc., and can be preferably used as agricultural films.

In addition, Snowtex 30 is a brand name of colloidal silica manufactured by Nissan Chemical Industries, Ltd .. Kayacryl resin H300 is a brand name of the acrylic emulsion of Nihon Kayaku Co., Ltd. make. Epiclon 860 is a trade name of a bisphenol A type epoxy compound manufactured by Dainippon Ing.

Reference Example 2

Replace the resin in the resin composition ③ of Example 2 with a commercially available ethylene-hexene copolymer (Sumikasen E FV403 density 0.919 g / cm 3, melt index 4 g / 10 min) polymerized using a metallocene catalyst. The film used for the inside and the outside layer can also be obtained by the method similar to Example 2. These films are excellent in toughness, antiblocking property, weather resistance, transparency, etc., and can be preferably used as agricultural films. In addition, when the lower antifogging film is formed on the film, the film is also excellent in antifogging property and anti-fogging property.

Formation of antifogging film

Alumina sol (manufactured by Nissan Chemical Co., Ltd., product name: Alumina sol 520, solid content 20%), colloidal silica (manufactured by Nissan Chemical Co., product name: Snowtex 20, solid content 20%), sodium dodecylbenzenesulfonate (manufactured by Kao, brand name: Neopel Rex F25) and sodium decanoate (manufactured by Nakarai Desk) were each diluted with water so as to have a solid content of 1.6, 0.4, 0.08, and 0.08, respectively, to prepare a coating solution, and one side of the film (the film before forming the anti-fogging film). Corona treatment is carried out, it is apply | coated to the surface so that solid content thickness may be about 0.1 g / m <2>, and air-dried at room temperature.

Reference Example 3

A film obtained by adding 2 wt% of sorbitan monostearate as an antifogging agent and 0.1 wt% of a fluorine-based surfactant (manufactured by Daikin Kogyo Co., Ltd., DS403) as an antifog to a film entire layer of Example 2 was obtained. The film is also excellent in antifogging property and anti-fogging property.

Radiation blocker Radiation Transmission Index (β) Total light transmittance (%) HAZE (%) Radiation Transmission Index (α) ΔQ (%) A (product A) (weight%) B (product made in B) (wt%) Example 1 11 One 13.8 92 15.2 14.4 3.8 Example 2 10 2 13.3 92 15.5 14.7 9.5 Comparative Example 1 12 0 14.0 92 15.5 14.0 0.0 Comparative Example 2 0 12 18.2 92 15.0 18.2 0.0 Radiation blocker A: Lithium aluminum composite hydroxide (trade name: Mizukalac; Mizusawa Chemical Co., Ltd .; refractive index: 1.53) Radiation shielding agent B: Aluminum silicate (trade name: Silton AMT08; Mizusawa Chemical Co., Ltd .; refractive index: 1.49 )

Examples 3, 4 and 5

0.4 parts by weight of hindered amine compound B, 0.2 parts by weight of antioxidant and 0.05 parts by weight of stearic acid amide were added to 100 parts by weight of low density polyethylene (trade name: Sumikasen F208-0; manufactured by Sumitomo Chemical Co., Ltd.). A predetermined amount of radiation shielding agent C (manufactured by A) and radiation shielding agent D (manufactured by B) as shown in 2 is added thereto, and mixed and kneaded at 140 DEG C for 5 minutes with a Banbury mixer, and then granulated in a granulator to obtain a composition pellet. Let this be the resin composition (4). An inflation molding machine is used to make a film with a film thickness of 0.1 mm and to evaluate the performance. The results are excellent as shown in Table 2.

The materials used in the procedure are as follows.

Hindered Amine Compound B Tinuvin 622LD (manufactured by Chiba Specialty Chemicals)

Antioxidant Irganox 1010 (manufactured by Chiba Specialty Chemicals)

Comparative Examples 3 and 4

A film was produced in the same manner as in Example 3 except that the amount of the radiation shielding agent was changed as shown in Table 2, and the performance thereof was evaluated. The results are inferior as shown in Table 2.

Radiation blocker Radiation Transmission Index β Total light transmittance (%) HAZE (%) Radiation Transmittance Indexα ΔQ (%) C (product made in A) (part by weight) D (product made in B) (weight part) Example 3 6.8 6.8 5.4 91 42.0 13.1 58.6 Example 4 10.2 3.4 2.3 91 32.8 10.5 78.1 Example 5 3.4 10.2 12.1 90 55.6 15.6 22.3 Comparative Example 3 13.6 0 8.0 92 24.2 8.0 0.0 Comparative Example 4 0 13.6 18.1 90 65.5 18.1 0.0 Radiation Blocker C Hydrotalcite (trade name: DHT-4A; manufactured by Kyogawa Chemical Co., Ltd .; refractive index: 1.51 radiation blocker D silicon oxide (trade name: Snowmark SP-3; long sematic manufacture; refractive index: 1.46)

Example 6

Laminated film having a film thickness of 0.1 mm using an inflation film molding machine with a resin composition ④ as an inner layer and low density polyethylene (trade name: Sumikasen F208-0; manufactured by Sumitomo Chemical Co., Ltd.) as an outer layer (inner layer: 0.05 mm, outer layer: 0.05 mm) is produced and performance is evaluated. The amount of the radiation blocker per 100 parts by weight of the resin in the laminated film is shown in Table 3. The evaluation results are excellent as shown in Table 3.

Comparative Examples 5 and 6

A film was produced in the same manner as in Example 5 except that the amount of the radiation shielding agent was changed as shown in Table 3, and the performance thereof was evaluated. The results are inferior as shown in Table 3.

Radiation blocker Radiation Transmission Index β Total light transmittance (%) HAZE (%) Radiation Transmittance Indexα ΔQ (%) C (product made in A) (part by weight) D (product made in B) (weight part) Example 6 3.3 3.3 16.2 92 24.4 27.5 41.0 Comparative Example 5 6.6 0 22.4 92 12.3 12.3 0.0 Comparative Example 6 0 6.6 32.5 92 47.9 47.9 0.0

According to the present invention, it is possible to obtain a resin film which effectively blocks radiation while transmitting visible light well.

Claims (20)

A radiation blocker (A agent) having a refractive index in the range of 1.47 to 1.65, a radiation blocker (B agent) having a different chemical composition from agent A, and a thermoplastic resin, wherein the total amount of the radiation blocker is 0.5 parts by weight or more per 100 parts by weight of the thermoplastic resin. A resin film, wherein the film has a radiation transmittance index of 35 or less at 23 ° C. and a total light transmittance of 80% or more. The resin film of Claim 1 whose alkali metal content rate of a radiation shielding agent is 3 weight% or less. The resin film according to claim 1 or 2, wherein the radiation transmittance index is 20 or less and the total light transmittance is 85% or more. The resin film as described in any one of Claims 1-3 whose refractive index of a radiation shielding agent (A agent) is 1.47-1.54. The resin film according to any one of claims 1 to 3, wherein the ratio (na / nr) of the refractive index (na) of the radiation blocking agent (A) to the refractive index (nr) of the thermoplastic resin is in the range of 0.95 to 1.05. The resin film according to any one of claims 1 to 3, wherein a ratio (na / nr) of the refractive index (na) of the radiation blocking agent (A) and the refractive index (nr) of the thermoplastic resin is in the range of 0.98 to 1.02. The resin film according to any one of claims 1 to 6, wherein the radiation blocking agent (B agent) is silicon oxide. The resin film of Claim 1 whose refractive index of a radiation shielding agent (B agent) is 1.47-1.65. The resin film according to claim 8, wherein the radiation transmittance index at 23 ° C is 25 or less and the total light transmittance is 85% or more. The resin film of Claim 8 or 9 whose refractive index of a radiation shielding agent (A agent) and / or a radiation shielding agent (B agent) is the range of 1.47-1.54. The ratio of the refractive index (na) of the radiation blocking agent (A agent), the refractive index (nb) of the radiation blocking agent (B agent) and the refractive index (nr) of the thermoplastic resin (na / nr) according to any one of claims 8 to 10. ) And (nb / nr) are both in the range of 0.95 to 1.05. The ratio of the refractive index (na) of the radiation blocking agent (A agent), the refractive index (nb) of the radiation blocking agent (B agent) and the refractive index (nr) of the thermoplastic resin (na / nr) according to any one of claims 8 to 10. ) And (nb / nr) are both in the range of 0.98 to 1.02. The resin film as described in any one of Claims 1-12 which satisfy | fills following formula when it is set as the compounding quantity A of a radiation shielding agent (A agent), and the compounding quantity B of a radiation shielding agent (B agent). 0.3 <A / (A + B) <0.7 The resin film according to any one of claims 1 to 13, which has two or more different layers. The resin film according to any one of claims 1 to 14, wherein the radiation transmittance index at 23 ° C is 15 or less, and the total light transmittance is 85% or more. The resin film of any one of Claims 1-15 which further contains 1 or more types chosen from a light stabilizer, a ultraviolet absorber, an anti-fog, an antifog, and a near-infrared blocker. The method according to claim 16, wherein at least one additive selected from the group consisting of 0.02 to 5% by weight of a light stabilizer, 0.01 to 3% by weight of an ultraviolet absorber, 0.01 to 3% by weight of an antifog and 0.1 to 4% by weight of an antifog Resin containing. The resin film as described in any one of Claims 13, 16, and 17 which has an antifogging film layer in at least one surface. The resin film according to any one of claims 1 to 18, which is used for facility horticulture. The resin film according to any one of claims 1 to 18, which is used for agricultural houses, tunnels, curtains or mulching.