WO2015079953A1

WO2015079953A1 - Agricultural film

Info

Publication number: WO2015079953A1
Application number: PCT/JP2014/080384
Authority: WO
Inventors: 拓野市村; 一也木下
Original assignee: 三菱樹脂株式会社
Priority date: 2013-11-29
Filing date: 2014-11-17
Publication date: 2015-06-04
Also published as: JPWO2015079953A1; JP5764729B1

Abstract

[Problem] The purpose of the present invention is to provide an agricultural film which uses an anti-fogging agent free of the problem of PFOA generation, the agricultural film having at least the same anti-fogging performance as conventional agricultural films, and retaining other required performances. [Solution] An agricultural film containing a fluorine-containing polyether composition containing: (a) a single-ended additive in which a group (F1 group) represented by formula (I): (CF₃)-(CF₂)₅-(CH₂)_n-CH(OH)CH₂- or a group (F2 group) represented by formula (II): (CF₃)-(CF₂)₅-(CH₂)_n-CH(CH₂OH)- is added to a single end of polyethylene glycol (in the formulas, n represents 1-10); (b) a double-ended additive in which an F1 group or an F2 group is added to both ends of the polyethylene glycol; and (c) double-ended hydroxyl-group-based polyethylene glycol, the fluorine-containing polyether composition having a fluorine content of 35 wt.% or more.

Description

Agricultural film

The present invention relates to an agricultural film containing a fluorine-containing polyether composition using a fluorine-containing epoxide as a raw material.

In recent years, in order to increase the productivity and market value of useful plants, so-called house cultivation and tunnel cultivation, in which useful plants are forcibly, semi-forcibly or restrained cultivated under an agricultural film coating, have been actively performed. As this agricultural film, vinyl chloride resin or polyolefin resin is currently used, but in any case, in order to promote the flow of water droplets on the inner surface of the film and increase the amount of sunlight incident, An antifogging agent (such as sorbitan fatty acid ester) which is a kind of surfactant is added to the film. Under the coating with a film containing such an antifogging agent, the temperature difference between the inside and outside of the house becomes large particularly in winter autumn and morning and evening, so that fog is likely to occur near the inner surface of the film. Since this fog is considered to be closely related to the quality of pests or harvested crops, it is necessary to suppress the generation of fog as much as possible in house cultivation and the like. Therefore, a fluorine-containing anti-fogging agent is added to the film to impart anti-fogging properties.

Conventionally, a compound containing a perfluoroalkyl group (Rf group) having 8 or more carbon atoms has been used as a fluorine-containing antifogging agent added to an agricultural film (see, for example, Patent Document 1).
However, recently, a compound containing a perfluoroalkyl group (Rf group) having 8 or more carbon atoms obtained by telomerization is perfluoro-octanoic acid (hereinafter abbreviated as “PFOA”) due to decomposition or metabolism of telomer. Has been announced by the US Environmental Protection Agency (EPA) (see EPA OPPT FACT SHEET April 14, 2003 (http://www.epa.gov/opptintr/pfoa/pfoafacts.pdf)).
EPA has also announced that it will strengthen scientific research against PFOA (EPA report “PRELIMINARY RISK ASSESSMENT OF THE DEVELOPMENTAL TOXICITY ASSOCIATED WITH EXPOSURE TO PERFLUOROOCTANOIC ACID AND ITS SALTS” (http: //www.epa .gov / opptintr / pfoa / pfoara.pdf)), and the environmental load of PFOA is a problem.

Therefore, in recent years, an attempt has been made to use a short-chain Rf group compound for the purpose of reducing the burden on the environment (see Patent Document 2 and the like), and generation of PFOA by reducing the number of carbon atoms to less than 8 Suppression is being studied.
However, an agricultural film having sufficient antifogging performance using a compound containing a perfluoroalkyl group (Rf group) having a carbon number of less than 8 has not been obtained.

JP 59-093739 A JP 2006-219586 A

The present invention uses an anti-fogging agent that does not manifest the problem of PFOA generation, has a performance equivalent to or better than the anti-fogging property of a conventional agricultural film, and maintains other required performance. The purpose is to provide.

The present invention has found that the above-mentioned problems can be solved by using a fluorine-containing polyether composition having a specific structure, and has completed the present invention.

That is, the present invention
[1] (a) One end of polyethylene glycol has the formula (I):
A group represented by (CF ₃ ) — (CF ₂ ) ₅ — (CH ₂ ) _n —CH (OH) CH ₂ — (F1 group) or formula (II):
Group represented by (CF ₃ ) — (CF ₂ ) ₅ — (CH ₂ ) _n —CH (CH ₂ OH) — (F2 group)
(Wherein n represents 1 to 10)
One-end adduct added by
(B) a fluorine-containing polyether composition comprising a both-end adduct in which F1 or F2 groups are added to both ends of the polyethylene glycol, and (c) a both-end hydroxyl group-type polyethylene glycol, An agricultural film comprising a fluorine-containing polyether composition having a fluorine content of 35% by weight or more.
[2] A reaction product of a both-end hydroxyl group-type polyethylene glycol and a fluorine-containing epoxide represented by the following formula (III):

(Wherein n represents 1 to 10)
One end adduct (a) is a 1: 1 molar ratio adduct of fluorine-containing epoxide and polyethylene glycol,
Both end adduct (b) is a 2: 1 molar ratio adduct of fluorine-containing epoxide and polyethylene glycol, and both end hydroxyl group-type polyethylene glycol is unreacted polyethylene glycol.
The agricultural film as described in [1].
[3] The agricultural film according to [1] or [2], wherein the fluorine content is 40% by weight or more.
[4] Agricultural use according to any one of [1] to [3], wherein the content of both terminal hydroxyl group-type polyethylene glycol is 10% by weight or less based on the total weight of the fluorine-containing polyether composition. the film.
[5] The agricultural film according to any one of [1] to [4], wherein the polyethylene glycol has an average molecular weight of 50 or more and less than 250.
[6] The agricultural film according to any one of [1] to [5], wherein the base resin is a vinyl chloride resin.
[7] Any one of [1] to [5], wherein the base resin is a polyolefin-based resin, has at least an outer layer, an intermediate layer, and an inner layer, and at least the outer layer includes the fluorinated polyether composition. Agricultural film according to 1.
It is about.

Since the agricultural film of the present invention uses an anti-fogging agent that does not manifest the problem of PFOA generation, the environmental load caused by the anti-fogging agent can be suppressed. It has a performance equivalent to or better than fog and can maintain other required performance.

The present invention relates to an agricultural film containing an antifogging agent comprising a fluorine-containing polyether composition having a specific structure.

Substrate Resin Agricultural film material (base resin) that can be used in the present invention generally has a film-forming ability that can be melt-molded at about 150 to 250 ° C., and is generally used for agricultural coatings. Any of those used can be used. For example, polyvinyl chloride resins such as polyvinyl chloride, polyolefin resins, and the like can be cited as representative examples, but are not limited to these resins.

In the present invention, the vinyl chloride resin refers to a copolymer in which vinyl chloride is the main component in addition to polyvinyl chloride. Examples of the monomer compound that can be copolymerized with vinyl chloride include vinylidene chloride, ethylene, propylene, acrylonitrile, maleic acid, itaconic acid, acrylic acid, methacrylic acid, and vinyl acetate. These vinyl chloride resins may be produced by any of the conventionally known production methods such as emulsion polymerization, suspension polymerization, solution polymerization, and bulk polymerization.

In the present invention, as the vinyl chloride resin, those having an average polymerization degree of 1000 or more and 2500 or less, preferably 1100 or more and 2000 or less can be used. May be. This mixing method is generally a method of mixing two kinds of resins at the time of film formation, but two kinds of resins with apparently different average degrees of polymerization are mixed by controlling the polymerization conditions during polymerization of the vinyl chloride resin. It may be the method that will be done.

In order to impart flexibility to the vinyl chloride resin film, 30 to 60 parts by weight, preferably 40 to 55 parts by weight of a plasticizer is blended with respect to 100 parts by weight of the resin. If it is less than 30 parts by weight, sufficient low-temperature physical properties cannot be obtained because of low flexibility at low temperatures. On the other hand, if it exceeds 60 parts by weight, the handleability (stickiness, etc.) at room temperature deteriorates and the workability at the time of film formation decreases, which is not preferable.

Examples of plasticizers that can be used include phthalic acid derivatives such as di-n-octyl phthalate, di-2-ethylhexyl phthalate, dibenzyl phthalate, and diisodecyl phthalate; isophthalic acid derivatives such as dioctyl phthalate; di-n-butyl adipate Adipic acid derivatives such as dioctyl adipate; maleic acid derivatives such as di-n-butyl malate; citric acid derivatives such as tri-n-butyl citrate; itaconic acid derivatives such as monobutyl itaconate; oleic acid such as butyl oleate Derivatives; ricinoleic acid derivatives such as glycerin monoricinoleate; epoxidized large oil, epoxy resin plasticizer, and the like. Moreover, in order to give a softness | flexibility to a resin film, it is not restricted to the above-mentioned plasticizer, For example, a thermoplastic polyurethane resin, a polyvinyl acetate, etc. can also be used.

Also, as a vinyl chloride resin, a blend of polyvinyl chloride and chlorinated polyethylene can be used. As the chlorinated polyethylene, the raw polyethylene is homopolymerization of ethylene or ethylene and 30% by weight or less (preferably 20% by weight or less) and 12 or less carbon atoms (preferably 3 to 9). Those obtained by copolymerization of α-olefins are preferred.

Specific examples of α-olefins include propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and the like. As polyolefin used as a raw material, what homopolymerized ethylene especially is preferable. As the chlorinated polyethylene, a method in which polyethylene powder or particles are chlorinated in an aqueous suspension or polyethylene dissolved in an organic solvent is chlorinated.

The blending amount of chlorinated polyethylene into the vinyl chloride resin is usually 0.5 to 20 parts by weight, preferably 0.5 to 10 parts by weight. The melt index of chlorinated polyethylene can be appropriately selected within the range of 0.5 to 150 g / 10 minutes.

Examples of polyolefin resins include α-olefin homopolymers, copolymers of α-olefin as a main component with different monomers, α-olefins and polyunsaturated compounds such as conjugated dienes or nonconjugated dienes, Examples include copolymers with acrylic acid, methacrylic acid, vinyl acetate and the like, such as high density, low density or linear low density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene. Examples include -4-methyl-1-pentene copolymer, ethylene-vinyl acetate copolymer, and ethylene-acrylic acid copolymer. Among these, low density polyethylene having a density of 0.910 to 0.935, ethylene-α-olefin copolymer, and ethylene-vinyl acetate copolymer having a vinyl acetate content of 30% by weight or less are transparent and weather resistant. It is preferable as an agricultural film from the viewpoint of properties and price. In the present invention, an ethylene-α-olefin copolymer resin obtained by copolymerization with a metallocene catalyst can be used as at least one component of the polyolefin resin.

This is usually referred to as metallocene polyethylene, and is a copolymer of ethylene and an α-olefin such as butene-1, hexene-1, 4-methylpentene-1, octene and the like. (Method A) (JP 58-19309, JP 59-95292, JP 60-35005, etc.) and (B) (JP 6-9724, JP 6-136195, No. 6-136196).

A polyolefin resin polymerized by using a metallocene compound, that is, a metallocene polyethylene, is not limited to the above methods (A) and (B) in that good initial transparency and transparency persistence of the film can be obtained. Can be used.

These polyethylene resins including metallocene polyethylene are classified by temperature rise elution fractionation (TREF), MFR, density, molecular weight distribution, and various other physical properties. Measurement of elution curve by temperature rise elution fractionation (Temperature Rising Election Fractionation: TREF) is described in "Journal of Applied Polymer Science.Vol 126,4,217-4,231 (1981)", "Polymer debate 1 C This is carried out based on the principle described in the literature such as “Showa 63”.

The ethylene-α-olefin copolymer used as at least one component of the polyolefin resin of the present invention has an MFR measured by JIS-K7210 of 0.01 to 10 g / 10 min, preferably 0.1 to 5 g / A value of 10 minutes is shown. If the MFR is larger than this range, the film meanders during molding and is not stable. On the other hand, if the MFR is too smaller than this range, the resin pressure at the time of molding increases and a load is applied to the molding machine. Therefore, the increase in pressure must be suppressed by reducing the production amount, which is not practical. Further, the ethylene-α-olefin copolymer used as at least one component of the polyolefin resin of the present invention has a density measured by JIS-K7112 of 0.880 to 0.930 g / cm ³ , preferably 0.8. A value of 880 to 0.920 g / cm ³ is shown. When the density is larger than this range, the transparency is deteriorated. On the other hand, if the density is smaller than this range, blocking occurs due to stickiness of the film surface, resulting in poor practicality.
The ethylene-α-olefin copolymer used as at least one component of the polyolefin resin of the present invention has a molecular weight distribution (weight average molecular weight / number average molecular weight) determined by gel permeation chromatography (GPC). The value is 1.5 to 3.5, preferably 1.5 to 3.0. When the molecular weight distribution is larger than this range, the mechanical strength is lowered, which is not preferable. If the molecular weight distribution is smaller than this range, the film meanders during molding and is not stable.

An ethylene-vinyl acetate copolymer resin having a vinyl acetate content in the range of usually 10 to 25% by weight, preferably 12 to 20% by weight can be used. If the vinyl acetate content is less than this range, the resulting film will be hard and will tend to wrinkle and sag when stretched in a house, which will have a negative effect on anti-fogging properties. If it is larger than the range, the melting point of the resin is low, so that the film loosens at high temperatures in summer during house extension, and is easily broken by wind and flapping with the house structure.

Bokirizai fluorine-containing polyether composition is a anti-fogging agent used in the present invention have the formula (III):

(Wherein n represents 1 to 10)
Is a mixture of nonionic compounds that can be produced by the reaction of a fluorine-containing epoxide represented by formula (II) with polyethylene glycol (PEG). Hereinafter, the fluorine-containing epoxide formula (III) may be expressed as CF ₃ (CF ₂ ) ₅ — (CH ₂ ) _n —CH (O) CH ₂ .

The fluorine-containing polyether composition used in the present invention can be produced by a conventional method using, for example, boron trifluoride (BF ₃ -OEt ₂ ) as a catalyst.
The reaction has the formula:
a CF ₃ (CF ₂ ) _5- (CH ₂ ) _n -CH (O) CH ₂ + b HO- (CH ₂ CH ₂ O) _m -X → Fluorine-containing polyether composition (where a is a raw material) The number of moles of fluorine epoxide, b is the number of moles of raw material PEG, X is a hydrogen atom or an alkyl group having 1 to 20 carbon atoms (preferably a methyl group), m is 1 to 10, and n is 1 to 10. .). Here, X is preferably a hydrogen atom. Further, n is preferably 1 to 5, and particularly preferably n = 1.

In order to obtain “one-end adduct (a)” of the fluorine-containing polyether composition used in the present invention, when the terminal X of PEG is, for example, a methyl group, the molar ratio of a: b = 1: 1. By reacting until the raw material fluorine-containing epoxide disappears, a compound in which the Rf group is completely added to one end of PEG (referred to as “one-end adduct (a)”) can be obtained. In this case, the other end of (a) is a methyl group.

On the other hand, when the terminal X of the PEG is a hydrogen atom (so-called both-end hydroxyl group-type PEG), the fluorine-containing epoxide can react with the hydroxyl groups at both ends of the PEG. Therefore, in the above reaction formula, a: b = 2: 1 If the reaction is continued until the raw fluorine-containing epoxide disappears, a compound in which Rf groups are completely added to both ends of PEG (referred to as “both end adduct (b)”) can be obtained. .

The fluorine-containing polyether composition used in the present invention can be produced by mixing the above-obtained (a) and (b) with both terminal hydroxyl group-type polyethylene glycol (c) at a predetermined molar ratio. .

Further, when the terminal X of PEG is a hydrogen atom, the fluorine-containing epoxide and the both-end hydroxyl group-type PEG in the above reaction formula have a molar ratio of a: b = 2: 1 or less, for example, a: b = 1: 1 mole. When the reaction is continued until the raw material fluorine-containing epoxide disappears, the one-end adduct (a) (the other end in this case is a hydrogen atom) and the both-end adduct ( A fluorine-containing polyether composition having a predetermined abundance ratio of b) and unreacted PEG (c) is obtained. The fluorine-containing polyether composition used in the present invention can also be produced by such a method. Moreover, in this manufacturing method, it becomes possible to obtain the fluorine-containing polyether composition which contains (a), (b) and (c) component by a predetermined existing molar ratio at a stretch.

The term “one-end adduct” as used herein specifically refers to
CF ₃ (CF ₂ ) _5- (CH ₂ ) _n -CH (OH) CH ₂ -O- (CH ₂ CH ₂ O) _m -X,
CF ₃ (CF ₂ ) _5- (CH ₂ ) _n -CH (CH ₂ OH) -O- (CH ₂ CH ₂ O) _m -X
(M, n and X are as defined above), and both end adducts specifically include
CF ₃ (CF ₂ ) _5- (CH ₂ ) _n -CH (OH) CH ₂ -O- (CH ₂ CH ₂ O) _m -CH ₂ CH (OH)-(CH ₂ ) _n- (CF ₂ ) ₅ CF ₃ ,
CF ₃ (CF ₂ ) _5- (CH ₂ ) _n -CH (OH) CH ₂ -O- (CH ₂ CH ₂ O) _m -CH (CH ₂ OH)-(CH ₂ ) _n- (CF ₂ ) ₅ CF ₃ ,
CF ₃ (CF ₂ ) _5- (CH ₂ ) _n -CH (CH ₂ OH) -O- (CH ₂ CH ₂ O) _m -CH ₂ CH (OH)-(CH ₂ ) _n- (CF ₂ ) ₅ CF ₃ ,
CF ₃ (CF ₂ ) _5- (CH ₂ ) _n -CH (CH ₂ OH) -O- (CH ₂ CH ₂ O) _m -CH (CH ₂ OH)-(CH ₂ ) _n- (CF ₂ ) ₅ CF ₃
It is.
Here, as the one-terminal adduct, the case where X = hydrogen atom is preferable.

The fluorine-containing polyether composition used in the present invention preferably has a fluorine content in the composition of 35% by weight or more, and more preferably 40% by weight or more. By making the fluorine content in the composition 35% by weight or more, the fog resistance of the agricultural film can be improved. The fluorine content in the fluorine-containing polyether composition can be confirmed by analysis by ¹³ F-NMR or the like.
Due to the environmental response of fluorine-based compounds, the performance of anti-fogging agents has been reduced, and many problems of fog generation have been pointed out. As a result of earnest investigation of the cause, it is becoming clear that this is a problem caused by insufficient balance between hydrophilicity and hydrophobicity and bleed-out characteristics of the fluorosurfactant used as an antifogging agent. The performance of the antifogging agent (antifogging performance) is determined by the balance between the hydrophobicity and hydrophilicity of the surface of the agricultural film to which the antifogging agent is added. As a result of conducting detailed studies for improvement by the present inventor, even when the carbon chain length of the antifogging agent is changed from C8 to C6 in consideration of environmental influences, the same antifogging property as in the past is obtained. In order to obtain, it has been found that the fluorine concentration also needs to be higher than the conventional one.

In the fluorine-containing polyether composition used in the present invention, the content of both terminal hydroxyl group-type PEG (or unreacted PEG) is preferably 10% by weight or less based on the total weight of the composition. The content of the both-end hydroxyl group-type PEG with respect to the total weight of the composition is more preferably 2 to 10% by weight, still more preferably 3 to 8% by weight. By setting the content of both-end hydroxyl group-type PEG in the composition within the above range, the fog resistance of the agricultural film can be improved.
Here, the content of the one-end adduct (a) and the both-end adduct (b), which is a component other than the both-end hydroxyl group-type PEG in the fluorine-containing polyether composition, is the total content of both. As long as it is 90% by weight or more with respect to the total weight, it can be arbitrarily selected within the range. For example, the content (% by weight) of the composition of the one-end adduct (a) and both-end adduct (b) with respect to the total weight is 0 to 90:90 to 0 (all exclude 0), or 10 to It can be in the range of 80: 80-10.
In addition, content of each component of a fluorine-containing polyether composition can be confirmed by analyzing by HPLC etc.

As described above, the fluorine-containing polyether composition used in the present invention is prepared by adding one end adduct and both end adducts, adding PEG corresponding to the unreacted content, It can also manufacture by adjusting so that it may become a mixture which has.

The fluorine-containing polyether composition used in the present invention is reacted with a fluorine-containing epoxide using a hydroxyl-terminated PEG with X being an H atom so that the composition of the fluorine-containing polyether composition falls within the above range. It can manufacture by controlling. The content of each component can be controlled by adjusting the molar ratio of fluorine-containing epoxide to PEG, the amount of catalyst, the reaction temperature, the reaction time, and the like.

PEG has a role to play a hydrophilic group in the fluorine-containing polyether composition of the present invention. As described above, PEG is particularly preferably a hydroxyl group at both ends as described above.
The average molecular weight of polyethylene glycol is preferably 50 or more and less than 250, more preferably 100 or more and less than 250, still more preferably 130 or more and 240 or less. Here, the average molecular weight means the number average molecular weight. By setting the average molecular weight of the polyethylene glycol within this range, it is preferable because both the water-repellent effect of the fluorine-containing polyether and the bleed-out property (appropriate bleed-out) from the resin can be achieved.
Depending on the molecular weight of PEG, hydrophilicity and bleed-out characteristics to the film surface change, and the surface characteristics of the added film differ. It has been found by our examination that the antifogging performance is determined by the balance between the hydrophilicity and hydrophobicity of the agricultural film surface to which the antifoggant is added. On the other hand, the carbon chain length of the perfluoroalkyl group that plays a role of hydrophobicity is being changed from C8 to C6, in which the carbon chain length that is difficult to be taken into living organisms is being considered in consideration of environmental influences. Under such changes, PEG with a relatively large molecular weight as used in conventional antifogging agents cannot maintain a good balance between hydrophilicity and hydrophobicity and bleedout characteristics to the film surface. When used as an agricultural film, there has been a great problem with the occurrence of diseases caused by fog. That is, in order to cope with the environment, when the carbon chain length of the perfluoroalkyl group of the antifogging agent is shortened from C8 to C6, the antifogging performance could not be maintained at the level required as an agricultural film. This time, in order to cope with such a situation, as a result of detailed analysis and examination, unexpectedly considering the environmental impact by making the molecular weight of PEG small compared to the conventional antifogging agent, and within the scope described in this application, and It has been found that sufficient fog prevention is obtained.
Two or more polyethylene glycols having an average molecular weight within the above range may be used. When two or more types are used, it is preferable that the average molecular weight as a whole polyethylene glycol calculated according to the composition ratio of various polyethylene glycols is also in the above range.

In the present invention, a specific structure among fluorine-containing polyether compositions containing a compound having a C ₆ F ₁₃ perfluoroalkyl group instead of a compound having a C 8 or more perfluoroalkyl group (Rf group) By using a composition having a fog as an antifogging agent, the problem of the occurrence of PFOA does not manifest, and an agricultural film having good fog prevention can be provided. That is, a conventional agricultural film is obtained by using a composition having a fluorine content (total fluorine concentration) in a specific range in a fluorine-containing polyether composition containing a compound having a C ₆ F ₁₃ perfluoroalkyl group. It is possible to achieve the same or better antifogging property. In addition, when a composition having a free polyethylene glycol content in a specific range is used, the fog resistance can be further improved.

The reaction of the fluorine-containing epoxide and the both-end hydroxyl group-type PEG is carried out using a catalyst and using a solvent, if necessary, with stirring in a temperature range of about 30 ° C. to 150 ° C. Suitable catalysts include group 12-15 and group 8 metal halides such as ZnCl ₂ , AlCl ₃ , SnCl ₄ , SbCl ₅ , FeCl ₃ , and BF ₃ (complex with ether or alcohol). Acid catalysts such as sulfuric acid and NaHSO ₄ can be used. The reaction time is not particularly limited, but is usually in the range of 1 to 24 hours in relation to the reaction rate and removal of reaction heat.

Anti-fogging agent can be made into an agricultural film by adding the anti-fogging agent to the base resin of agricultural film such as vinyl chloride resin and polyolefin resin, mixing and melting, and then processing into a film by a conventional method. .

When the base resin is a vinyl chloride resin, the addition amount of the antifogging agent is usually 0.01 to 2.0 parts by weight, preferably 0.02 to 2.0 parts by weight with respect to 100 parts by weight of the base resin. 1.0 part by weight. If the amount is less than 0.01 parts by weight, sufficient fog prevention cannot be obtained. If the amount is more than 2.0 parts by weight, it is disadvantageous in terms of cost. In addition, bleeding out to the film surface, coloring of the film itself, and transparency There is a risk of problems such as deterioration of the sexiness. Therefore, by setting the addition amount of the antifogging agent within the above range, it is possible to obtain an agricultural vinyl chloride resin film that is excellent in antifogging properties and has other various performances.

When the base resin is a polyolefin-based resin, the amount of the antifogging agent can be appropriately selected within a range that does not impair the effects of the present invention. The amount is from 01 to 2.0 parts by weight, preferably from 0.02 to 1.0 parts by weight.
Moreover, when base resin is polyolefin resin, it can be set as the polyolefin resin multilayer film which has an outer layer, an intermediate | middle layer, and an inner layer at least. In this case, it is preferable to contain an antifogging agent in at least the outer layer of the multilayer film, and the addition amount of the antifogging agent is preferably 0.001 to 5.5 based on 100% by weight of the polyolefin resin in the outer layer of the multilayer film. It is 0% by weight, more preferably 0.01 to 3.0% by weight.
In the present invention, the inner layer of the multilayer film may contain an antifogging agent. The amount of the antifogging agent added is preferably 0.001 with respect to 100% by weight of the polyolefin resin in the inner layer of the multilayer film. To 5.0 wt%, more preferably 0.01 to 3.0 wt%, still more preferably 0.001 to 0.09 wt%, and particularly preferably 0.001 or more and less than 0.05 wt%.
By setting the content of the anti-fogging agent within the above range, a sufficient anti-fogging effect can be exhibited, and surface stickiness due to white turbidity or bleed out of the film can be suppressed.

The agricultural film of the present invention preferably uses an antifoggant and an antifogging agent in combination.
As the antifogging agent, a sorbitan antifogging agent is preferably used. As the sorbitan antifogging agent, sorbitan fatty acid ester and its alkylene oxide adduct can be used. In the present invention, the sorbitan antifogging agent is preferably sorbitan palmitic acid ester, alkylene oxide adduct of sorbitan palmitic acid ester, sorbitan stearic acid ester, alkylene oxide adduct of sorbitan stearic acid ester, polyoxyalkylene sorbitan fatty acid ester And at least one selected from the group consisting of sorbitan alkylene oxide adducts and sorbitan monopalmitate.
In the present invention, the sorbitan stearate ester and sorbitan palmitate ester include monoesters, diesters, triesters, and mixtures thereof.
As the alkylene oxide added to sorbitan stearic acid ester and sorbitan palmitic acid ester, ethylene oxide and propylene oxide are preferable. Regarding the number of moles to which the alkylene oxide is added, if the number of moles is large, the initial wetting and the low temperature drip resistance are effective, but the sustainability tends to be low.

In the present invention, the sorbitan antifogging agent includes sorbitan palmitate 0.5 mol propylene oxide adduct, polyoxypropylene sorbitan fatty acid ester, sorbitan monostearate 0.5 mol propylene oxide adduct, and sorbitan monopalmitin. Particularly preferred is at least one selected from the group consisting of acid esters.

In the present invention, the content of the antifogging agent such as a sorbitan antifogging agent is such that when the base resin is a polyolefin resin multilayer film that is a polyolefin resin, the polyolefin resin 100 in the intermediate layer of the multilayer film. The content is preferably 0.1 to 3.0% by weight, more preferably 0.5 to 2.0% by weight with respect to the weight%. By setting the content of the sorbitan antifogging agent in the above range, good initial antifogging property can be obtained.

In the present invention, an antifogging agent other than the sorbitan antifogging agent can be contained in the film within a range not impairing the effects of the present invention.
Other antifogging agents that can be used in the present invention include glycerin monopalmitate, glycerin monostearate, glycerin monolaurate, diglycerin monopalmitate, glycerin dipalmitate, glycerin distearate, diglycerin mono Glycerin surfactants such as palmitate monostearate, triglycerin monostearate, triglycerin distearate or their adducts with alkylene oxide, polyethylene glycol monostearate, polyethylene glycol monopalmitate, polyethylene glycol alkylphenyl Polyethylene glycol surfactants such as ether, and other trimethylolpropane surfactants such as trimethylolpropane monostearate and pentaerythritol. Pentaerythritol surfactants such as allyl monopalmitate and pentaerythritol monostearate, alkylene oxide adducts of alkylphenols; esters of sorbitan / glycerin condensate and fatty acid, sorbitan / alkylene glycol condensate and fatty acid ester Diglycerin diolate sodium lauryl sulfate, sodium dodecylbenzenesulfonate, cetyltrimethylammonium chloride, dodecylamine hydrochloride, lauric acid laurylamide ethyl phosphate, triethylcetylammonium iodide, oleylaminodiethylamine hydrochloride, dodecylpyridinium salt, etc. And those containing isomers thereof.

In the agricultural film of the invention, various additives usually used for synthetic resins can be used in combination. Examples of such additives include weather resistance improvers (hindered amine light stabilizers, UV absorbers, etc.), weather resistance agents, infrared absorbers, heat retention agents, fillers, metal organic acid salts, basic organic acid salts. And overbased organic acid salts, hydrotalcite compounds, epoxy compounds, β-diketone compounds, polyhydric alcohols, halogen oxyacid salts, sulfur-based, phenol-based and phosphite-based antioxidants, heat stabilizers, lubricants , Antistatic agents, colorants, antiblocking agents, and the like.

As the hindered amine light stabilizer, a hindered amine light weathering agent usually blended for agricultural use can be used. For example, a hindered amine compound (having at least two piperidine ring structures in the molecule and having a molecular weight of 500 or more) Hereinafter, “piperidine ring-containing hindered amine compound”) can also be preferably used.

Examples of the piperidine ring-containing hindered amine compound include bis (1,2,2,6,6-pentamethyl-4-piperidyl) -2-butyl-2- (3,5-ditert-butyl-4-hydroxybenzyl). ) Malonate, tetra (2,2,6,6-tetramethyl-4-piperidyl) butanetetracarboxylate, tetra (1,2,2,6,6-pentamethyl-4-piperidyl) butanetetracarboxylate, bis ( 2,2,6,6-tetramethyl-4-piperidyl) · di (tridecyl) butanetetracarboxylate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) · di (tridecyl) butanetetra Carboxylate, 3,9-bis [1,1-dimethyl-2- {tris (2,2,6,6-tetramethyl-4-piperidyloxy Carbonyloxy) butylcarbonyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, 3,9-bis [1,1-dimethyl-2- {tris (1,2,2 , 6,6-pentamethyl-4-piperidyloxycarbonyloxy) butylcarbonyloxy} ethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, 1,5,8,12-tetrakis [4 , 6-Bis {N- (2,2,6,6-tetramethyl-4-piperidyl) butylamino} -1,3,5-triazin-2-yl] -1,5,8,12-tetraaza Dodecane, 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol / dimethyl succinate condensate, 2-tert-octylamino-4,6-dichloro-s-triazi / N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine condensate, N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) ) Hexamethylenediamine / dibromoethane condensate.

Further, commercially available hindered amine compounds, TINUVIN 770, TINUVIN 780, TINUVIN 144, TINUVIN 622LD, TINUVIN NOR 371, CHIMASSORB 119FL, CHIMASSORB 944 (above, manufactured by Ciba Geigy Corp.), Sanol LS-765 (manufactured by Sankyo LS LA, KMA-MA R. -68, MARK LA-68, MARK LA-62, MARK LA-67, MARK LA-57, LA-900, LA-81, NO-Alkyl-1 (above, manufactured by ADEKA), UV-3346, UV- 3529, UV-3581, UV-3853 (from Cytec), Hostabin N20, Hostabin N24, Hostabin N30, Hostabin 845, Hostabin NOW, Sa NDUBOA PR-31, Nyrostub S-EED (manufactured by Clariant Japan), UVINUL5050H (manufactured by BASF Japan), and the like can be used. These piperidine ring-containing hindered amine compounds are used alone or in combination of two or more.

The content of the hindered amine compound is 0.001 to 5% by weight, preferably 0.01 to 1% by weight, based on 100% by weight of the base resin of the agricultural film. When the content is less than 0.001% by weight, a sufficient effect cannot be obtained, and when the content is more than 5% by weight, the effect is not improved, and the physical properties of the film are deteriorated.

Moreover, the copolymer of ethylene (A) and the cyclic amino vinyl compound (B) represented by following formula (1) can also be added to the agricultural film of this invention.

In the formula (1), R1 and R2 each independently represent a hydrogen atom or a methyl group, R3 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and preferably R1 and R2 are each a methyl group And R3 is a hydrogen atom.

The vinyl compound (B) represented by the formula (1) can be synthesized by a known method, for example, the method described in JP-B-47-8539, JP-A-48-65180, or the like.

Representative examples of the vinyl compound (B) represented by the formula (1) include 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1,2,2,6,6. -Pentamethylpiperidine, 4-acryloyloxy-1-ethyl-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-1-propyl-2,2,6,6-tetramethylpiperidine, 4-acryloyl Oxy-1-butyl-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1,2,2,6,6- Pentamethylpiperidine, 4-methacryloyloxy-1-ethyl-2,2,6,6-tetramethylpiperidine, 4-methacryloyloxy-1-buty -2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-1-propyl-2,2,6,6-tetra A methyl piperidine etc. can be mentioned.

The ethylene / cyclic aminovinyl compound copolymer preferably has a ratio of the (B) to the sum of the ethylene (A) and the cyclic aminovinyl compound (B) of 0.0005 to 0.85 mol%, More preferred is 0.001 to 0.55 mol%. That is, the preferred copolymer is one having a high light stability for a low content of the vinyl monomer having a hindered amine group in the side chain (cyclic aminovinyl compound (B)). When the concentration of the cyclic aminovinyl compound (B) is 0.0005 mol%, a sufficient light stabilizing effect is exhibited. On the other hand, when it exceeds 0.85 mol%, it tends to be substantially uneconomical.

Further, the ethylene / cyclic aminovinyl compound copolymer is such that (B) is not continuous in two or more in the copolymer, and the ratio of being isolated is 83% or more based on the total amount of (B), Preferably it is 90% or more.

The content of the ethylene / cyclic aminovinyl compound copolymer is preferably 0.5 to 15 parts by weight, particularly preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the resin constituting the film. If this content is less than the above range, the weather resistance is inferior because it is inferior.

Examples of commercially available ethylene / cyclic aminovinyl copolymers that can be used include Novatec® LD / XJ100H (manufactured by Nippon Polychem Co., Ltd.).

Examples of the ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 5,5′-methylenebis (2-hydroxy-4-methoxybenzophenone), etc. 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-ditert-butylphenyl) benzotriazole, 2- ( 2'-hydroxy-3 ', 5'-ditert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzo Triazole, 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, 2- 2- (2'-hydroxyphenyl) such as 2'-hydroxy-3'.5'-dicumylphenyl) benzotriazole, 2,2'-methylenebis (4-tert-octyl-6-benzotriazolyl) phenol Benzotriazoles: phenyl salicylate, resorcinol monobenzoate, 2,4-ditertiarybutylphenyl-3 ′, 5′-ditertiarybutyl-4′-hydroxybenzoate, 2,4-ditertiaryamylphenyl-3 ′ , 5'-ditert-butyl-4'-hydroxybenzoate, hexadecyl-3,5-ditert-butyl-4-hydroxybenzoate, etc .; 2-ethyl-2'-ethoxyoxanilide, 2-ethoxy Substituted oxanilides such as -4'-dodecyl oxanilide; ethyl-α-cyano-β, β-diphenyl acrylate, Cyanoacrylates such as til-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate; 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- [ (Hexyl) oxy] -phenol, 2- [4,6-bis (2,4-dimethylphenyl) -1,3,5-triazin-2-yl] -5- (octyloxy) phenol and other triazines can give. These ultraviolet absorbers are used alone or in combination of two or more.

The ultraviolet absorber can be added in an amount of preferably more than 0.001% and less than 2% by weight, more preferably 0.01 to 1% by weight with respect to 100% by weight of the base resin of the agricultural film. If the content is less than the above range, the effect of improving weather resistance is low, and if it exceeds the above range, there are problems such as a decrease in transparency due to bleeding out.

Favorable heat retention can be imparted to the agricultural film in the present invention by adding an infrared absorber. As the infrared absorber, an inorganic compound (inorganic oxide, inorganic hydroxide, hydrotalcite, etc.) containing at least one atom of Mg, Ca, Al, Si and Li that is effective as a heat retaining agent can be used.

Especially, when the hydrotalcite infrared absorber represented by the following formula (2) is used, a film that is inexpensive and has good moldability can be obtained.
_{_{_{_{Mg 4.5 Al 2 (OH) 13}}}} CO 3 · 3.5H 2 O (2)

In particular, when an infrared absorber represented by the following formula (3) is used, a film that is inexpensive and has good moldability can be obtained.
[Al ₂ (Li _(1-x) · M _{(x + y)} ) (OH) _{6 + y} ] ₂ (An ⁻ ) _{2 (1 + x) / n} · mH ₂ O (3) (wherein M is Mg and / or Zn A is an n-valent anion, m is 0 or a positive number, and x and y are in the range of 0 ≦ x <1, 0 ≦ y ≦ 0.5.)

The method for obtaining the infrared absorber (heat retention agent) represented by the above formula (3) is not particularly limited, and commercially available products can be used, for example, DHT4A, SYHT-3 (manufactured by Kyowa Chemical Co., Ltd.) HT-P (manufactured by Sakai Chemical Co., Ltd.), Optima (manufactured by Toda Kogyo Co., Ltd.), Mizukarak (manufactured by Mizusawa Chemical Co., Ltd.), and the like.

The infrared absorbing agent (heat insulating agent) is an inorganic fine particle having infrared absorbing ability, and these can be used alone or in combination of two or more. The inorganic fine particles that can be used are not particularly limited, but inorganic compounds containing at least one atom selected from the components: Si, Al, Mg, and Ca can be used. For example, magnesium oxide, calcium oxide, aluminum oxide, silicon oxide, lithium hydroxide, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, magnesium carbonate, calcium carbonate, calcium sulfate, magnesium sulfate, aluminum sulfate, lithium phosphate, calcium phosphate , Magnesium silicate, calcium silicate, aluminum silicate, calcium aluminate, magnesium aluminate, sodium aluminosilicate, potassium aluminosilicate, calcium aluminosilicate, kaolin, clay, talc, mica, zeolite, hydrotalcite compounds and the like. These may be obtained by dehydrating crystal water.

The inorganic fine particles may be natural products or synthetic products. The inorganic fine particles can be used without being limited by the crystal structure, crystal particle diameter, and the like.

The content of the inorganic fine particles is preferably more than 0.1% by weight and less than 15% by weight, more preferably 1 to 12% by weight with respect to 100% by weight of the base resin of the agricultural film. If the content is less than the above range, the effect of improving heat retention is low, and if it exceeds the above range, there are problems such as a decrease in transparency.

Examples of the metal species constituting the organic acid salt, basic organic acid salt and overbased organic acid salt of the metal include Li, Na, K, Ca, Ba, Mg, Sr, Zn, Cd, Sn, Cs, Examples of the organic acid include carboxylic acid, organic phosphoric acid, and phenol.

Examples of the filler include silica, talc, aluminum hydroxide, hydrotalcite, calcium sulfate, calcium silicate, calcium hydroxide, and hydroxide in order to suppress stickiness of the film or to further increase the heat retention. Magnesium, kaolin clay, mica, alumina, magnesium carbonate, sodium aluminate, conductive zinc oxide, lithium phosphate and the like are used. One type of these fillers may be used, or two or more types may be used in combination.

Examples of the phenolic antioxidant include 2,6-ditert-butyl-p-cresol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3,5-ditert-butyl-4- Hydroxyphenyl) -propionate, distearyl (3,5-ditert-butyl-4-hydroxybenzyl) phosphonate, thiodiethylene glycol bis [(3,5-ditert-butyl-4-hydroxyphenyl) propionate], 1,6 -Hexamethylene bis [(3,5-ditert-butyl-4-hydroxyphenyl) propionate] and the like.

Examples of the sulfur-based antioxidant include dialkylthiodipropionates such as dilauryl thiodipropionate, dimyristyl, and distearyl, and β-alkyl mercapto of polyols such as pentaerythritol tetra (β-dodecyl mercaptopropionate). And propionic acid esters.

Examples of the phosphite antioxidant include trisnonylphenyl phosphite, tris (2,4-ditert-butylphenyl) phosphite, tris [2-tert-butyl-4- (3-tert-butyl- 4-hydroxy-5-methylphenylthio) -5-methylphenyl] phosphite.

Examples of the colorant include phthalocyanine blue, phthalocyanine green, hansa yellow, alizarin lake, titanium oxide, zinc white, ultramarine blue, permanent red, quinacridone, and carbon black.

The agricultural film of the present invention can contain the above-described components in combination, and can further contain the following optional components as necessary. Optional components include other stabilizers, impact resistance improvers, cross-linking agents, fillers, foaming agents, antistatic agents, nucleating agents, plate-out preventing agents, surface treatment agents, flame retardants, fluorescent agents, anti-glare agents Agents, bactericides, metal deactivators, mold release agents, pigments, processing aids and the like.

The agricultural film of the present invention is each weighed in a necessary amount for blending various additives, and blending machines such as a ribbon blender, a Banbury mixer, a Henschel mixer, a super mixer, a single or twin screw extruder, a roll, and a kneading machine. Any other known blending machine or mixing machine may be used. In order to form the resin composition thus obtained into a film, a method known per se, for example, a melt extrusion molding method (including a T-die method and an inflation method), calendar processing, roll processing, extrusion molding processing, Blow molding, inflation molding, melt casting, pressure molding, paste processing, powder molding, and the like can be suitably used.

The thickness of the agricultural film of the present invention is preferably in the range of 0.01 to 1 mm, more preferably 0.05 to 0.5 mm, still more preferably 0.05 to 0 in terms of strength and cost. .2 mm. If the thickness is within this range, an agricultural film free from problems of strength, molding and workability can be obtained.

Moreover, when the agricultural film of this invention is a polyolefin-type agricultural film, it can also be set as a multilayer film of 3 layers to 5 layers. The layer ratio constituting the three-layer film is preferably in the range of 1 / 0.5 / 1 to 1/5/1 from the viewpoint of moldability, transparency and strength, and 1/2/1 to 1/4/1. The range of is more preferable. Further, the ratio between the outer layer and the inner layer is not particularly specified, but it is preferable that the ratio is approximately the same because of the curl property of the obtained film.
In the case of polyolefin multilayer films, various additives such as the above weather resistance improvers (hindered amine light stabilizers, UV absorbers, etc.), weather resistance agents, infrared absorbers, and heat retention agents are added to all layers. It may also be added to some layers (intermediate layer or intermediate layer and intermediate layer as outer layer).

Moreover, the agricultural film of the present invention can form an antifogging coating film and other coating films. For example, an antifogging coating film may be formed on the inner surface when an agricultural film is coated on a house, and a dustproof coating film may be formed on the outer surface.

Examples of the antifogging coating film include a composition mainly composed of a binder resin such as an inorganic colloidal sol and / or a thermoplastic resin. Preferably, an antifogging coating film mainly comprising an inorganic colloid substance and a hydrophilic organic compound or an antifogging coating film comprising an inorganic colloid substance and an acrylic resin as main components can be used. Further, the binder resin may not be added, and an inorganic material such as colloidal silica or colloidal alumina may be laminated.

As the inorganic colloidal sol, inorganic aqueous colloidal particles such as silica, alumina, water-insoluble lithium silicate, iron hydroxide, tin hydroxide, titanium oxide, barium sulfate were dispersed in water or a hydrophilic medium by various methods. And aqueous sols. Among these, silica sol and alumina sol are preferably used, and these may be used alone or in combination.

As the inorganic colloidal sol, it is preferable to select an average particle size in the range of 5 to 100 nm. Within this range, two or more colloidal sols having different average particle sizes may be used in combination. By setting the average particle size within this range, the coating does not become white and devitrified, and the stability of the inorganic colloidal sol is good.

The inorganic colloidal sol is blended in an amount of 0.2 to 5 and preferably 0.5 to 4 in terms of a solid weight ratio with respect to the total solid weight of the binder resin composition. That is, when the blending amount is too small, a sufficient antifogging effect may not be exhibited. On the other hand, when the blending amount is too large, the antifogging effect is not easily improved in proportion to the blending amount. The film formed later becomes cloudy and causes a phenomenon that the light transmittance of the film is lowered, and the film may be coarse and brittle, which is not preferable.

Examples of the binder resin include acrylic resins, epoxy resins, urethane resins, and polyester resins. When the base film is a polyolefin film, it is particularly preferable to use an acrylic resin and / or a urethane resin from the viewpoint of compatibility with the polyolefin film, and more preferably (a) a hydrophilic acrylic heavy film described later. Those made of coalescence, (c) those made of a hydrophobic acrylic resin, and (e) those made of a hydrophobic acrylic resin and a polyurethane emulsion have their respective characteristics and are preferable.

Examples of the acrylic resin include (a) one made of a hydrophilic acrylic polymer, (b) one made of a block copolymer containing a hydrophobic molecular chain block and a hydrophilic molecular chain block in one molecule, (c ) What consists of hydrophobic acrylic resin is mentioned. When the base film is a polyolefin-based film, (a) is particularly excellent in compatibility with the base film in terms of early antifogging and wetting, while (c) is preferable with the base film. It is excellent in compatibility.

As the hydrophilic acrylic polymer (a), a hydroxyl group-containing vinyl monomer component is a main component (preferably 60 wt% to 99.9 wt%, more preferably 65 wt% to 95 wt%), acid Examples thereof include a copolymer containing 0.1 to 30% by weight of a group-containing vinyl monomer component, a partially neutralized product or a completely neutralized product thereof. Examples of the hydroxyl group-containing vinyl monomer component include hydroxyalkyl (meth) acrylates such as hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2- Examples include hydroxypropyl (meth) acrylate, but are not limited thereto. These may be homopolymers, or may be copolymers of these hydroxyalkyl (meth) acrylates as main components and other monomers that can be copolymerized therewith.

Examples of the acid group-containing monomer copolymerizable with these hydroxyalkyl (meth) acrylates include carboxylic acids, sulfonic acids, and phosphonic acids, and (meth) acrylic acid belonging to carboxylic acids is particularly preferable.

Examples of other copolymer components include styrene, vinyl terene, vinyl chloride, vinylidene chloride, vinyl oxide, (meth) acrylic acid esters, N, N-dimethylaminoethyl (meth) acrylamide, vinyl pyridine and the like.

As the hydrophobic acrylic resin (c), at least a total of 60% by weight of a monomer comprising an alkyl ester of acrylic acid or methacrylic acid, or a single unit of an alkyl ester of acrylic acid or methacrylic acid and an alkenylbenzene. A monomer mixture and 0 to 40% by weight of a copolymerizable α, β-ethylenically unsaturated monomer are obtained by emulsion polymerization in an aqueous medium in the presence of an emulsifier, for example, according to ordinary polymerization conditions. And water dispersible polymers or copolymers.

Examples of alkyl esters of acrylic acid or methacrylic acid used for the production of hydrophobic acrylic resins include acrylic acid methyl ester, acrylic acid ethyl ester, acrylic acid-n-propyl ester, acrylic acid isopropyl ester, acrylic acid-n- Examples thereof include butyl esters. Generally, alkyl acrylates having 1 to 20 carbon atoms and / or methacrylic acid alkyl esters having 1 to 20 carbon atoms are used. Examples of alkenylbenzenes include styrene, α-methylstyrene, vinyltoluene and the like.

Examples of α, β-ethylenically unsaturated monomers used for obtaining hydrophobic acrylic resins include α, β such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, crotonic acid, and itaconic acid. -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; acrylic acid or methacrylic acid Hydroxyl group-containing vinyl monomers such as hydroxyethyl; acrylonitriles; acrylic amides; glycidyl esters of acrylic acid or methacrylic acid, and the like. These monomers may be used alone or in combination of two or more, and are preferably used in the range of 0 to 40% by weight. If the amount used is too large, the antifogging performance may be lowered, which is not preferable.

The acrylic resin is a known emulsifier, for example, an anionic surfactant, a cationic surfactant, or a nonionic surfactant, in the presence of one or more kinds in an aqueous medium. It can be obtained by a method of emulsion polymerization, a method of polymerization using a reactive emulsifier, a method of polymerizing based on an oligo soap theory without containing an emulsifier.

Examples of the polymerization initiator preferably used for the production of the acrylic resin include persulfates such as ammonium persulfate and potassium persulfate. These can be used in the range of 0.1 to 10% by weight based on the total amount of monomers charged.

It is particularly preferable to use a hydrophobic acrylic resin having a glass transition temperature of 35 to 80 ° C. If the glass transition temperature is too low, the inorganic colloidal particles are agglomerated several times and tend to be in a non-uniform dispersion state. If it is too high, it is difficult to obtain a transparent uniform coating.

The hydrophobic acrylic resin is preferably used as an aqueous emulsion. An aqueous emulsion obtained by polymerization of each monomer in an aqueous medium may be used as it is, or may be diluted by adding a liquid dispersion medium to this, and also produced by the above polymerization. A polymer may be collected separately and re-dispersed in a liquid dispersion medium to form an aqueous emulsion.

On the other hand, examples of the (d) urethane-based resin include polyether-based, polyester-based, and polycarbonate-based anionic polyurethane aqueous compositions and emulsions. When the base film is a polyolefin-based film, a polycarbonate-based anionic polyurethane emulsion is preferable from the viewpoint of adhesion of the anti-fogging coating film to the base film, water resistance and scratch resistance, and further anti-fogging coating. A polycarbonate-based anionic polyurethane emulsion containing a silanol group is more preferable from the viewpoints of improvement in water resistance and scratch resistance of the film, time until the antifogging property is developed, and antifogging durability. These may be used alone or in combination of two or more.

A polycarbonate-based anionic polyurethane emulsion containing a silanol group comprises a polyurethane resin containing at least one silanol group in the molecule and a strongly basic tertiary amine as a curing catalyst. Refers to a colloidal dispersion system (emulsion) in which the silanol group-containing polyurethane resin and the strongly basic tertiary amine are dissolved in the aqueous phase, or a colloidal dispersion system in which fine particles are dispersed.

The aqueous polyurethane composition is preferably 0.01 or more and 2 or less, more preferably 0.01 or more and 1 or less, based on the hydrophobic acrylic resin in terms of solid content by weight. When it is less than 0.01, it is difficult to improve the scratch resistance, and it takes a long time until the antifogging property is exhibited, and it is difficult to exhibit a sufficient antifogging effect. In addition, when it is too much, not only the scratch resistance is difficult to improve in proportion to the blending amount, but the coating film formed after coating tends to become cloudy and lower the light transmittance, which is also disadvantageous in terms of cost. It is not preferable.

When preparing an antifogging agent composition for forming an antifogging coating film, an anionic surfactant, a cationic surfactant, a nonionic surfactant, a polymer surfactant, etc. An activator can be added. The following can be used as such a surfactant.

Anionic surfactants include fatty acid salts such as sodium oleate and potassium oleate; higher alcohol sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate; alkylbenzene sulfones such as sodium dodecylbenzenesulfonate and sodium alkylnaphthalenesulfonate Acid salt and alkyl naphthalene sulfonate salt; naphthalene sulfonic acid formalin condensate; dialkyl sulfosuccinate salt; dialkyl phosphate salt; polyoxyethylene sulfate salt such as sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate, etc. Can be mentioned.

Cationic surfactants include: ethanolamines; laurylamine acetate, triethanolamine monostearate formate; amine salts such as stearamide ethyl diethylamine acetate; lauryltrimethylammonium chloride, stearyltrimethylammonium chloride, dilauryldimethyl And quaternary ammonium salts such as ammonium chloride, distearyldimethylammonium chloride, lauryldimethylbenzylammonium chloride, and the like.

Nonionic surfactants include polyoxyethylene higher alcohol ethers such as polyoxyethylene lauryl alcohol, polyoxyethylene lauryl ether and polyoxyethylene oleyl ether; polyoxyethylene such as polyoxyethylene octylphenol and polyoxyethylene nonylphenol. Alkylaryl ethers; polyoxyethylene acyl esters such as polyethylene glycol monostearate; polypropylene glycol ethylene oxide adducts; sorbitan fatty acid esters such as sorbitan monostearate, sorbitan monopalmitate, sorbitan monobenzoate; diglycerin monopalmi Diglycerol fatty acid esters such as tate and diglycerol monostearate; glycerol monostearate Glycerin fatty acid esters such as pentaerythritol monostearate; pentaerythritol fatty acid esters such as dipentaerythritol monopalmitate; dipentaerythritol fatty acid esters such as dipentaerythritol monopalmitate; sorbitan monopalmitate half adipate Sorbitan such as half glutamic acid ester and diglycerin fatty acid / dibasic acid esters; or condensates thereof with alkylene oxide such as ethylene oxide and propylene on oxide such as polyoxyethylene sorbitan monolaurate and polyoxypropylene sorbitan monostearate Rate of polyoxyethylene stearylamine, polyoxyethylene oleylamine, polyoxyethylene stearamide, etc. Polyoxyethylene alkyl amine fatty acid amides; sugar esters.

Examples of the polymer surfactant include polyacrylate, polymethacrylate, and cellulose ethers.

The addition of the surfactant can easily and quickly disperse the binder resin and the inorganic colloid sol, and when used in combination with the inorganic colloid sol, imparts hydrophilicity to the surface of the hydrophobic polyolefin resin film. Fulfills the function. The addition amount of the surfactant is preferably selected in the range of 0.1 to 50 parts by weight with respect to 100 parts by weight of the solid content of the resin. If the amount of the surfactant added is too small, it takes time to sufficiently disperse the resin and the inorganic colloid sol, and the antifogging effect in combination with the inorganic colloid sol cannot be sufficiently exhibited. If the amount added is too large, the transparency of the coating will decrease due to the bleed-out phenomenon on the coating surface formed after coating, and if it is noticeable, it may cause deterioration of the blocking resistance of the coating or decrease the water resistance of the coating. .

When preparing an antifogging agent composition for forming an antifogging coating film, a crosslinking agent can be added. A crosslinking agent has an effect which bridge | crosslinks acrylic resin especially and improves the water resistance of a coating film. Examples of the crosslinking agent include phenol resins, amino resins, amine compounds, aziridine compounds, azo compounds, isocyanate compounds, epoxy compounds, silane compounds, etc., but particularly amine compounds and aziridine compounds. Epoxy compounds can be preferably used.

In the antifogging agent composition used in the present invention, a liquid dispersion medium can be blended as necessary. Such a liquid dispersion medium includes a hydrophilic or water-miscible solvent containing water, water; monohydric alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; polyhydric alcohols such as ethylene glycol, diethylene glycol, and glycerin. Examples: cyclic alcohols such as benzyl alcohol; cellosolve acetates; ketones and the like. These liquid dispersion media may be used alone or in combination.

The anti-fogging agent composition can be further mixed with conventional additives such as an antifoaming agent, a plasticizer, a film-forming aid, a thickening agent, a pigment, and a pigment dispersant as necessary. Further, as a binder component other than the acrylic resin, for example, a polyether-based, polycarbonate-based, or polyester-based water-dispersible urethane resin may be mixed.

In order to form an antifogging coating film on the surface of a base film, generally a solution or a dispersion of an antifogging composition is applied to a doctor blade coating method, a roll coating method, a dip coating method, a spray coating method, or a rod coating method, respectively. A known coating method such as a bar coating method, a knife coating method, or a brush coating method may be employed and dried after coating. The drying method after coating may be either natural drying or forced drying. When the forced drying method is employed, it is usually 50 to 250 ° C., preferably 70 to 200 ° C. Good. For heating and drying, an appropriate method such as a hot air drying method, an infrared drying method, a far infrared drying method, and an ultraviolet curing method may be employed, and it is advantageous to adopt the hot air drying method in consideration of the drying speed and stability. is there.

The thickness of the anti-fogging coating film may be selected based on 1/10 or less of the base film, but is not necessarily limited to this range. If the thickness of the coating film is larger than 1/10 of the base film, there is a difference in flexibility between the base film and the coating film, so that a phenomenon such as peeling of the coating film from the base film is likely to occur. Moreover, the phenomenon that a crack occurs in the coating film to reduce the strength of the base film occurs, which is not preferable.

If the adhesion between the base film and the coating film derived from the antifogging agent composition is not sufficient, the base film may be subjected to a surface treatment. Examples of the surface treatment method include corona discharge treatment, sputter etching treatment, sodium treatment, and sandblast treatment. In the corona discharge treatment method, discharge is performed between a needle-like or knife-edge electrode and a counter electrode, and a sample is placed between the electrodes, and the film surface contains oxygen such as aldehyde, acid, alcohol peroxide, ketone, ether, etc. This is a process for generating a functional group. In the sputter etching process, a sample is placed between electrodes that are performing low-pressure glow discharge, and a large number of fine protrusions are formed on the film by the impact of positive ions generated by the glow discharge. In the sandblasting process, fine sand is sprayed on the film surface to form a large number of fine irregularities on the surface. Among these surface treatments, corona discharge treatment is preferable from the viewpoints of adhesion to the coating layer, workability, safety, cost, and the like.

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

Hereinafter, the present invention will be described in more detail based on examples and comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

(1) Preparation of laminated film As a three-layer inflation molding device, 100 mmφ (made by Pla Koken Co., Ltd.) was used for a three-layer die. Is 40 mmφ (manufactured by Pla Giken Co., Ltd.), the outer layer extruder temperature is 180 ° C., the intermediate layer extruder temperature is 170 ° C., the die temperature is 180 to 190 ° C., the blow ratio is 2.0 to 3.0, the take-off speed is 3 to A three-layer laminated film having the components shown in Tables 1 to 3 was obtained at 7 m / min, thicknesses of 0.1 mm and 0.15 mm. Since these films are used with the end of the tube cut open when the house is stretched, the tube outer layer during film formation becomes the inner layer (inner surface) of the house when stretched when unfolded.

[Composition] The amount added is as described in each table.
HP-LDPE: Branched polyethylene produced with a high-pressure radical catalyst (MFR: 0.8 g / 10 min, density 0.922) “F022NH” manufactured by Ube Maruzen Polyethylene
Metallocene PE: An ethylene / α-olefin copolymer produced with a metallocene catalyst (MFR: 2 g / 10 min, density 0.907) Kernel “KF270” manufactured by Nippon Polychem
EVA1: Ethylene / vinyl acetate copolymer (vinyl acetate content 5% by weight, MFR 2 g / 10 min)
EVA2: Ethylene / vinyl acetate copolymer (vinyl acetate content 15% by weight, MFR 2 g / 10 min)

Fluorosurfactant A: Perfluoroalkylethylene oxide adduct (carbon number of perfluoroalkyl group is 6, fluorine content: 43% by weight, free PEG content: 8% by weight, average molecular weight of PEG: 240)
Fluorosurfactant B: Perfluoroalkylethylene oxide adduct (carbon number of perfluoroalkyl group is 6, fluorine content: 38% by weight, free PEG content: 6% by weight, PEG average molecular weight: 460)
Fluorosurfactant C: Perfluoroalkylethylene oxide adduct (carbon number of perfluoroalkyl group is 6, fluorine content: 33% by weight, free PEG content: 13% by weight, average molecular weight of PEG: 460)
Fluorosurfactant D: Perfluoroalkylethylene oxide adduct (carbon number of perfluoroalkyl group is 6, fluorine content: 27% by weight, free PEG content: 15% by weight, average molecular weight of PEG: 630)
Fluorosurfactant E: Perfluoroalkylethylene oxide adduct DS-405 (perfluoroalkyl group having 8 carbon atoms) (Daikin Chemicals Sales Co., Ltd.)
Fluorosurfactants A to D were synthesized using the method described in WO2011 / 030725.
The fluorine content was measured by ¹³ F-NMR, and the free PEG content was measured by HPLC.

UV absorber A: Benzophenone UV absorber UV-531
UV absorber B: triazine UV absorber UV-1164
Synthetic hydrotalcite A: “DHT4A” manufactured by Kyowa Chemical Co., Ltd.

Light stabilizer A: chimassorb944FD
Light stabilizer B: tinivin NOR371FF
Ethylene / Cyclic aminovinyl copolymer: “Novatech LD / XJ100H” manufactured by Nippon Polyethylene Co., Ltd. MFR = 3 g / 10 min (190 ° C., JIS-K6760) Density = 0.931 g / cm ³ (JIS-K6760) Cyclic amino Vinyl compound content = 5.1% by weight (0.7 mol%) Percentage of cyclic aminovinyl compound present in isolation = 90 mol% Melting point = 111 ° C.

(2) Surface treatment of the film The outer layer surface of the obtained tubular film was subjected to corona discharge treatment at a discharge voltage of 120 V, a discharge current of 4.7 A and a line speed of 10 m / min, and the “wetting index” according to JIS-K6768 was measured. ,confirmed.

(3) Formation of antifogging coating film The main component (silica sol and / or alumina sol) shown below, a thermoplastic resin, a crosslinking agent and a liquid dispersion medium were blended to obtain an antifogging agent composition.

The antifogging agent composition was blended as follows.
Inorganic colloidal sol (colloidal silica) 4.0
Thermoplastic resin (Sanmor SW-131: hydrophobic binder resin) 3.0
Cross-linking agent (TAZM) 0.1
Dispersion medium (water / ethanol = 3/1) 93
(Note) The amount of inorganic colloidal sol is indicated by the amount of inorganic particles, and the amount of thermoplastic resin is indicated by the solid content of the polymer.

Colloidal silica: Snowtex 30 manufactured by Nissan Chemical Industries, average particle size of 15 nm
Sunmole SW-131: acrylic emulsion T.M. manufactured by Sanyo Kasei Co., Ltd. A. Z. M: Aziridine-based compound manufactured by Mutual Pharmaceutical Company

The above antifogging agent composition was applied to the surface of the base film surface-treated in (2) using a # 5 bar coater. The applied film was kept in an oven at 80 ° C. for 1 minute to volatilize the liquid dispersion medium to form an antifogging coating film. The thickness of the coating film of each obtained film was about 1 μm.

The following tests were conducted for each type (film thickness 100 μm) provided with an antifogging coating film. Each test method in Examples and Comparative Examples is shown below.

(1) Fog generation test The film sample obtained above was stitched to a predetermined size for pipe house extension, and the film was extended to a pipe house constructed in a field in Matsusaka City, Mie Prefecture. Eight pipe houses with a frontage of 3.6m, a building height of 2.4m, and a depth of 9m were constructed, and each building was covered with four types of the above-mentioned films at different times, so that the film immediately after being stretched and after loading could be evaluated ( September 2013, November 2013). Inside the house, cultivated sengiku from mid-October, and observed and evaluated the occurrence of fog in the house with the naked eye.
The evaluation of fog generation was performed twice: two days (mid-September 2013) immediately after coating the film on the pipe house, and two days (mid-November 2013), two months after coating. .
The degree of fog generation was observed 18 times per day for 2 hours from 9:00 am to 5:00 pm, and the results were shown in Tables 1 and 2 as “mist evaluation” according to the following classification.
The evaluation value of “fog generation evaluation” has the following significance.
(Double-circle): The state which fog generation is not seen at all in the house, or it has generate | occur | produced only in the film inner surface vicinity.
○: Fog is generated throughout the house, but the back of the house 9m away can be clearly identified.
Δ: fog is slightly dark throughout the house and the depth of the house 7 meters ahead cannot be clearly identified.
X: A state where fog is densely formed throughout the house, and the depth of the house 4 m ahead cannot be identified at all.
Judgment was made based on the most frequently occurring value (same time at each house) observed within two days.

(2) Antifogging property The antifogging judgment criterion was determined based on the time until water droplets start flowing under conditions where condensation does not occur easily.
Observation conditions:
The surface on which the coating film of the molded product is formed is placed in the upper part of the water tank filled with water, and the outside air temperature is kept at 12 ° C and the water temperature inside the water tank is kept at 22 ° C. The speed of cloudiness was observed with the naked eye and showed the time until the water droplets started to flow.
Also, the antifogging property was evaluated according to the following evaluation criteria depending on the time until water droplets started to flow.
A: The time until the water droplet starts flowing is shorter than 60 minutes.
○: The time until the water droplet starts flowing is shorter than 60 minutes and shorter than 90 minutes.
X: The time until the water droplet starts flowing is 90 minutes or more.

(3) Presence or absence of PFOA (perfluorooctanoic acid) content When PFOA (perfluorooctanoic acid) is contained in the fluorosurfactant component used, “Yes” is indicated. It was written as “nothing”.

[Examples 1 and 2, Comparative Examples 1 and 2]
By the above blending, a three-layer film (antifogging coating application type) having a film thickness of 100 μm and a layer ratio of 1/3/1 was prepared, and antifogging and antifogging properties were evaluated by the above methods. The results are shown in Table 1.

[Examples 3 to 4, Comparative Examples 3 to 4]
With the above blending, a three-layer film (antifogging coating application type) having a film thickness of 100 μm and a layer ratio of 1/3/1 was prepared, and the fog resistance was evaluated by the above method. The results are shown in Table 2.

[Example 5, Comparative Example 5]
With the above formulation, a three-layer film (antifogging coating application type) having a film thickness of 150 μm and a layer ratio of 1/3/1 was prepared, and whether or not PFOA was contained by the above method is shown in Table 2.

As is apparent from the above results, the agricultural film according to the present invention does not contain PFOA, has excellent antifogging properties (Examples 1 to 4), and further has excellent antifogging properties (Examples). 1-2).
Therefore, according to the present invention, the problem of the occurrence of PFOA is not manifested, the load on the environment due to the antifogging agent can be suppressed, and further, the antifogging property is equal to or higher than that of the conventional agricultural implement application film, It is possible to provide an agricultural film having other required performance.

Claims

(A) At one end of polyethylene glycol, the formula (I):
A group represented by (CF 3 ) — (CF 2 ) 5 — (CH 2 ) n —CH (OH) CH 2 — (F1 group) or formula (II):
Group represented by (CF 3 ) — (CF 2 ) 5 — (CH 2 ) n —CH (CH 2 OH) — (F2 group)
(Wherein n represents 1 to 10)
One-end adduct added by
(B) a fluorine-containing polyether composition comprising a both-end adduct in which F1 or F2 groups are added to both ends of the polyethylene glycol, and (c) a both-end hydroxyl group-type polyethylene glycol, An agricultural film comprising a fluorine-containing polyether composition having a fluorine content of 35% by weight or more.
A reaction product of a both-end hydroxyl group-type polyethylene glycol and a fluorine-containing epoxide represented by the following formula (III):

(Wherein n represents 1 to 10)
One end adduct (a) is a 1: 1 molar ratio adduct of fluorine-containing epoxide and polyethylene glycol,
Both end adduct (b) is a 2: 1 molar ratio adduct of fluorine-containing epoxide and polyethylene glycol, and both end hydroxyl group-type polyethylene glycol is unreacted polyethylene glycol.
The agricultural film according to claim 1.
The agricultural film according to claim 1 or 2, wherein the fluorine content is 40% by weight or more.
The agricultural film according to any one of claims 1 to 3, wherein the content of both-end hydroxyl group-type polyethylene glycol is 10 wt% or less based on the total weight of the fluorine-containing polyether composition.
The agricultural film according to any one of claims 1 to 4, wherein the polyethylene glycol has an average molecular weight of 50 or more and less than 250.
6. The agricultural film according to claim 1, wherein the base resin is a vinyl chloride resin.
The agricultural resin according to any one of claims 1 to 5, wherein the base resin is a polyolefin resin, has at least an outer layer, an intermediate layer, and an inner layer, and at least the outer layer includes the fluorine-containing polyether composition. the film.