JPH0372549A - Synthetic resin film for agricultural use - Google Patents

Abstract

PURPOSE:To improve mist protecting effect without spoiling weather resistance, high frequency-adhesive properties, etc., by compounding a synthetic resin with a surfactant which is a specified fluorinated organosilicon compd. and making it into a film. CONSTITUTION:100 pts.wt. synthetic resin (e.g. PVC) are compounded with 0.005-0.5 pt.wt. surfactant selected from a fluorinated organosilicon compd. of formula I (wherein Rf is a 4-20C fluoroalkyl wherein O may be substd. for one or more C atoms in the chain; R is H or a group contg. a 1-10C monovalent hydrocarbon; A and B are each a divalent org. group; (m) is 0-1; (n) is 1-3; (x) is 2-3; and (y) is 1-50) and a fluorinated organosilicon compd. of formula II and, if necessary, other anti-fog additive, plasticizer, metal soap., lubricant, coloring agent, etc., and the mixture is made into a film to obtain the title film with a thickness of 0.03-0.2mm.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an agricultural synthetic resin film.

[Conventional technology]

In recent years, as in so-called greenhouse cultivation and tunnel cultivation, agricultural crops are grown under a covering material made of synthetic resin film, etc., and marketability and productivity are increased by promoting, suppressing, or protecting crop growth. This is particularly popular.

Synthetic resin films commonly used in greenhouse cultivation and tunnel cultivation are polyvinyl chloride films and polyethylene films. Since the surface of these synthetic resin films is hydrophobic, water droplets form on the inner surface when used as a covering material for greenhouse cultivation. In order to promote the flow of water droplets, an antifogging agent consisting of a sorbitan-based or glycerin-based surfactant is usually added to the resin film.

However, when a synthetic resin film with this antifogging agent added is used as a coating material, fog may form near the inner surface of the coating material in the morning, evening, night, or during rain when the temperature difference between the inside and outside of the house is large. There is.

This fog generation phenomenon wets the leaves, stems, flowers, and fruits of crops cultivated in greenhouses and tunnels, causing the occurrence of various diseases and aiding in the spread of diseases, and also reducing the need for extra fuel to dry the crops. There is a disadvantage of doing so.

In order to eliminate such problems, methods have been used to suppress the humidity inside greenhouses such as greenhouses by irrigation methods or by covering the soil with mulch materials, but these methods have not sufficiently solved the above problems. In order to solve this problem, an anti-fogging agricultural synthetic resin film further added with a silicone surfactant has recently been proposed (Japanese Patent Publication No. 31742/1983).
.

In addition, a method for further incorporating fluorine-based surfactants into antifogging agricultural films has been developed and put into practical use (Japanese Patent Publication No. 59-35573, Japanese Patent Publication No. 60-1982).
-28860 Publication, Special Publication No. 60-50378,
Special Publication No. Sho 62-49906, Special Publication No. Sho 62-1293
Publication No. 2, Special Publication No. 62-10126, Special Publication No. 63
-14739, etc.).

[Problem to be solved by the invention]

However, in the synthetic resin film to which silicone surfactant has been added, it is necessary to add a fairly large amount of silicone surfactant in order to obtain the effect of preventing fog generation, and as a result, the films are not easily bonded to each other. Another disadvantage is that the adhesion is poor during high-frequency bonding.

In addition, in synthetic resin films to which the above-mentioned fluorosurfactants are added, the weather resistance of the synthetic resin film may be impaired,
Problems such as a decrease in high-frequency adhesion, an increase in water absorption and whitening, and a delay in the start-up time of the antifogging effect occurred.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an agricultural synthetic resin film which eliminates the drawbacks associated with the prior art and has an excellent fog-proofing effect.

[Means to solve the problem]

The present invention was obtained as a result of intensive research, and is intended to achieve the above-mentioned object. is a fluoroalkyl group (however, at least one carbon atom in the chain may be substituted with an oxygen atom), and R is a hydrogen atom or a group containing a monovalent hydrocarbon having 1 to 10 carbon atoms. , A and B are divalent organic groups, m is an integer of 0 or 1, n is an integer of 1 to 3, X is an integer of 2 or 3, and y is an integer of 1 to 3. It is an integer of 50. ] and the general formula (■
): [Here, two Rf, A, B, m,
x and y may be the same or different and are as defined above. The present invention provides a synthetic resin film.

In the compounds of the general formulas (, I) and (II) used as surfactants in the synthetic resin film of the present invention, the fluoroalkyl group having 4 to 20 carbon atoms represented by Rf is, for example, the formula (■ ):C,%Fta◆, -(I[
[) [Here, n represents an integer of 4 to 20, preferably 5 to 12] A perfluoroalkyl group represented by: at least one carbon atom in the main chain of such perfluoroalkyl group Typical examples of those substituted with oxygen atoms include perfluoroalkyl ether groups represented by formula (■): [Here, m represents an integer of 1 to 5, preferably 2 to 4]; and general formula: % Examples include fluoroalkyl groups represented by the formula %) [where p is an integer of 2 to 10].

Among the above-exemplified fluoroalkyl groups having 1 to 20 carbon atoms, perfluoroalkyl groups represented by general formula (III) and general formula (IV) are preferred.

Specific examples of the perfluoroalkyl group of formula (III) include nonafluorobutyl group, tridecafluorohexyl group, heptadecafluorooctyl group, 7-trifluoromethylhexadecafluorooctyl group, 5-trifluoromethyldodeca Specific examples of the perfluoroalkyl ether group of formula (IV) include 1-trifluoromethyl-2-oxa-octafluoropentyl group, 1,4-bis(trifluoromethyl ) -2,5-dioxa-undecafluorooctyl group and 1,4.7-tris(trifluoromethyl)-2,5,8-trioxa-tetradecafluoroundecyl group.

Examples of the group represented by R containing a monovalent hydrocarbon group having 1 to 10 carbon atoms include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, and decyl; cyclohexyl groups, etc. Cycloalkyl groups such as methylphenyl group, ethylphenyl IH12,4-dimethylphenyl group, mesityl group, propylphenyl group; aralkyl groups such as benzyl group, 2-phenylethyl group, 1-phenylethyl group, etc. A monovalent hydrocarbon group having 1 to 10 carbon atoms; Formula: % Formula % [Here, R'' is a monovalent hydrocarbon group having 1 to 10 carbon atoms.] etc. Examples include groups.

The divalent organic group represented by A is, for example, 2 Formula: -(CIhOCHz)r-CHCHz- [Here, R2 is a hydrogen atom or a methyl group, and l is an integer of 0 or l. ] It is a group represented by, and specific examples include,
In addition, for example, the formula: %Formula% [Here, n is an integer from O to 3. ]-(CHz)
-C-0-Cfi*-CHz-Ch-.

1 [Here, n is an integer from 0 to 3. ]-]CH2CH
A group represented by 2-O-C-CIC1h)-CHt-1 can be mentioned.

The group represented by Rf-A- above is, for example, represented by the formula: Rf
A compound of general formula (1) or (U) is produced by a known addition reaction using a platinum-based catalyst between a compound having a vinyl group at the terminal of -A'-co-ox and a suitable corresponding compound having an H-Si bond. (In this example, the reaction produces a group A represented by the formula A''-C1,C1,-).

The divalent organic group represented by B is, for example, a divalent hydrocarbon group having 1 to 7 carbon atoms, such as a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, etc. ~7 alkylene groups, and further formula: % formula %) [Here, Y is a divalent hydrocarbon group having 1 to 7 carbon atoms as exemplified above, and R is a hydroxyalkyl group or an alkyl group. It is. ] Groups represented by these can be mentioned.

In addition, formula (V) included in general formula (1), (I[)
Examples of the polyether group represented by (CxHzxO)y-(V) [where X and y are as described above] include a polyethylene glycol chain, a polypropylene glycol chain, and a combination of ethylene oxide and propylene oxide. Examples include polymer chains. In the case of a copolymer chain, it may be in the form of either a block polymer or a random polymer.

The polyether group of general formula (V) is general formula (■), (n
) imparts hydrophilicity to the fluorine-containing organosilicon compound,
It has the effect of exhibiting a fog-proofing effect. The fog-proofing effect obtained depends on the balance between the perfluoroalkyl group Rf and the polyether group. Generally, the ratio of the molecular weight of the polyether group/molecular weight of the perfluoroalkyl group Rf is from 80/20 to 10/90, preferably from 70/30 to
It is 30/70.

The group represented by the formula -8-0-(CXHzxO) y-R included in general formulas (1) and (II) can also be introduced by a hydrosilylation reaction using a platinum catalyst in the same manner as described above, and a person skilled in the art can It is self-evident.

As a specific example of the organosilicon compound of general formula (1) explained above, e CsF+tCHzCHzSi(CHz)so(CHzC
HzO) to Mee.

Moreover, as a specific example of the organosilicon compound of general formula (II), etc. are mentioned.

The surfactant added to the synthetic resin film of the present invention is:
Either one of the fluorine-containing organosilicon compounds represented by the above general formulas (1) and (It) or a combination of both may be used.

Examples of the synthetic resin that is the base material of the agricultural synthetic resin film of the present invention include vinyl chloride resin; ethylene resin such as low density polyethylene, linear low density polyethylene, and ethylene vinyl acetate resin.

The amount of the surfactant consisting of the compound of general formula (I) and/or (II) added to the synthetic resin as the base material is 0.005 to 0.5 parts by weight, preferably 0.005 to 0.5 parts by weight, based on 10011 parts of the synthetic resin. It is 0.01 to 0.2 parts by weight. 0.0
If the amount is less than 0.5 parts by weight, the fog prevention effect will be small, and even if it is added in excess of 0.5 parts by weight, no improvement will be observed in the fog prevention effect or durability, but rather there will be a tendency for the adhesion to decrease.

Furthermore, as the antifogging agent to be added to the synthetic resin film of the present invention, any of the ones that have been conventionally used as an antifogging agent (or sometimes referred to as a drip-proofing agent) in agricultural synthetic resin films can be used. For example, antifogging agents made of polyhydric alcohol partial esters consisting of polyhydric alcohols and higher fatty acids, antifogging agents having a chemical structure in which alkylene oxide is added to the antifogging agents, etc. are suitable. Can be mentioned. Specific examples of such antifogging agents include sorbitan monostearate, sorbitan monopalmitate,
Sorbitan antifogging agents such as sorbitan monobehenate, ester of sorbitan/glycerin condensate and higher fatty acid, ester of sorbitan/alkylene glycol Wi compound and higher fatty acid; glycerin monopalmitate, glycerin monostearate, Glycerin antifogging agents such as glycerin sesquipalmitate and dicrycerin monopal ξtate; polyethylene glycol antifogging agents such as polyethylene glycol monostearate, polyethylene glycol monopalmitate, polyethylene glycol alkyl phenyl ether; trimethylolpropane mono Trimethylolpropane antifogging agents such as stearate and trimethylolpropane monopalmitate; pentaerythritol antifogging agents such as pentaerythritol monopalmitate and dipentaerythritol monostearate; or those containing isomers thereof. Included.

In addition, the resin composition constituting the synthetic resin film of the present invention may contain various commonly used additives as necessary. Examples of such additives include plasticity, metal These include soaps, epoxy resins, heat stabilizers such as chelators, lubricants, ultraviolet absorbers, colorants, etc.

The synthetic resin film of the present invention can be produced by blending the various components described above to prepare a predetermined composition and molding it into a film using a conventional method, for example, using a calendar. The synthetic resin film of the present invention usually has a thickness of 0.03 to 0.2 mm, although it is not particularly limited.

Further, the synthetic resin film of the present invention may be subjected to dustproof coating using an acrylic resin. - As the acrylic resin constituting the dustproof coating layer on the film, any acrylic resin conventionally used in the field of agricultural coating materials can be used. Although the thickness of the coating layer is not strictly limited, it is generally advantageous to range from 1 to 10 μm, preferably from 1 to 5 μm.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

~l゛ and 6l~5 In each of the Examples and Comparative Examples, various components were mixed in the composition shown below, and the resulting mixture was calendered to 190°C.
A film having a thickness of 1100 a was produced by rolling at 'C.

vArli,: Polyvinyl chloride (P = 1300) 100 parts by weight dioctyl phthalate 45 parts by weight tricresyl phosphate 3 parts by weight Zn-C
a-based composite stabilizer 3 parts by weight Epoxy resin 2 parts by weight Sorbitan monostearate 1.5 parts by weight 1 part phosphite chelator 0.5 parts by weight Surfactant: Examples 1 to 11: Surface activity shown in Table 1 Agent 0.1 parts by weight Comparative Example 1 0 parts by weight Comparative Example 2 Dimethyl silicone oil 0.3 parts by weight (Shin-Etsu Chemical Co., Ltd., KF96) Comparative Example 3 Silicone surfactant 0.3 parts by weight (
Shin-Etsu Chemical Co., Ltd., H-32) Comparative Example 4 Fluorine surfactant 0.1 part by weight (
Daikin Industries, Ltd., DS-401) Comparative Example 5 Fluorine surfactant 0.1 part by weight (
Asahi Glass Co., Ltd., Surflon S-393) In each of the Examples and Comparative Examples, the films obtained as described above were subjected to the following tests. In addition, for the heat resistance test, a film having a thickness of 1 mm was prepared and used in the same manner as described above. The results are shown in Table 2.

(1) Fog generation test A test film is placed on the sloped ceiling of a fog observation frame surrounded by wooden boards on all sides, placed on a pre-prepared water bath with a water temperature of approximately 40°C, and left at room temperature of 25°C for one week. . Then,
While keeping the water bath at 40”C, lower the room temperature to 5°C and
After a period of time, the occurrence of fog near the inner surface of the film is observed with the naked eye.

[Evaluation criteria for fog generation degree]

: No fog formation was observed.

±: Very slight fog is observed.

+: Considerable fog generation is observed.

++: Generation of a very large amount of fog is observed.

(2) Drip-proof test The film was spread on a single-roof mini-house with a 5-degree inclination on January 9, 1989 at a test field in Ishibe-cho, Koka-gun, Shiga Prefecture, and the time required for water droplets attached to the inner surface of the film to flow out was measured. The initial drip-proof performance was evaluated. In addition, the flow state after one day was observed with the naked eye.

[Evaluation criteria for flow condition]

○: Flowing uniformly over the entire surface.

Δ: Adhesion of water droplets is observed in half.

×: Water droplets are observed on the entire surface.

(3) Haze value (
Transparency was evaluated by measuring the degree of haze.

(4) The sticky film was stored in a constant temperature and humidity chamber at 30°C and 60% for one month, and then the feel was evaluated in a constant temperature room at 23°C.

[Evaluation criteria for stickiness]

O: Good stickiness Δ: Slightly sticky ×: Considerably sticky (5) After the water-absorbing whitening film was immersed in warm water at 40° C. for 24 hours, the degree of whitening was evaluated using a haze value using a haze meter.

(6) High-frequency weldability The films obtained in the test (4) were welded using a high-frequency sewing machine (manufactured by Nippon Koshuha ■), and then the degree of peeling was evaluated.

(Evaluation criteria for high frequency weldability) 0: The entire surface is well adhered.

ΔD There is some peeling.

×: The entire surface is peeled off.

(7) The time required for the heat-resistant film to blacken was measured with the gear open at 185°C.

〔Effect of the invention〕

The agricultural synthetic resin film of the present invention is an anti-fog agricultural film with a high fog-proofing effect, and furthermore has heat resistance, transparency,
Excellent high frequency adhesion, water absorption and whitening properties, etc.

Claims (1)

[Claims] 1) Synthetic resin and general formula (I) added to the synthetic resin: ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) [Here, Rf is the number of carbon atoms 4 to 20 fluoroalkyl groups (however, at least one carbon atom in the chain may be substituted with an oxygen atom), R is a hydrogen atom or a monovalent hydrocarbon having 1 to 10 carbon atoms A and B are divalent organic groups, m is an integer of 0 or 1, n is an integer of 1 to 3, x is an integer of 2 or 3, and y is an integer from 1 to 50. ] A fluorine-containing organosilicon compound represented by and the general formula (
II): ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) [Here, each of the two Rf, A, B, m, x and y may be the same or different, as defined above] An agricultural synthetic resin film comprising at least one surfactant selected from fluorine-containing organosilicon compounds represented by: