JPH0624798B2 - Agricultural soft vinyl chloride resin film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides an agricultural soft vinyl chloride resin having excellent anti-fogging properties and anti-fog properties, and having excellent durability for a long period of time. It's about film.

[Prior Art] In recent years, farmers cultivating useful plants have come to widely adopt a method of accelerating or suppressing cultivation of useful plants in a house (greenhouse) or a tunnel for the purpose of improving profitability. It was

As a covering material for this house (greenhouse) or tunnel,
Polyethylene film, ethylene-vinyl acetate copolymer film, polyester film, polycarbonate film, vinyl chloride resin film, glass and the like are used. Among them, the soft vinyl chloride resin film has light transmittance, heat retention, and
It is widely used because it has the best overall mechanical strength, durability, workability and economy.

The film used as a covering material for the house or the tunnel has condensed water attached to the inner surface of the film, which is excellent in so-called "anti-fog property" in that it flows down along the inner surface of the film without being dropped onto cultivated crops. In addition, it is required to have so-called "fog resistance" that can suppress fog and mist generated in a house or tunnel, maintain appropriate humidity, and suppress the occurrence of diseases.

As a method for improving the antifogging property, there is a method of kneading a so-called antifogging agent such as a fatty acid ester of glycerin and a fatty acid ester of sorbitan into a base resin. In this method, the bleeding of the antifogging agent from the film is performed. However, since the effect of anti-fogging property is diminished after one year has passed after the film was spread on a house, improvement of anti-fogging durability has been studied.

Further, as a method of imparting anti-fog property, a method of kneading a fluorocarbon surfactant into a base resin is known. (For example, JP-A-57-14648) However, in this method, the bleeding of the fog-preventing agent from the surface of the film is fast, and like the previous anti-fog agent, about one year after the spreading, the fog-proofing There is a drawback that the effect is reduced.

[Object of the Invention] An object of the present invention is to provide a vinyl chloride resin film for agricultural use in which undesired deterioration phenomena such as deterioration of antifogging property and antifog property are significantly improved.

[Structure of the Invention] However, the gist of the present invention is that an antifogging agent composition containing silica sol and / or alumina sol and a binder as main components on one surface of a fluorosurfactant-containing soft vinyl chloride resin film. A soft vinyl chloride resin film for agriculture, which is characterized in that a film derived from is formed.

Hereinafter, the present invention will be described in detail.

In the present invention, the vinyl chloride resin includes not only polyvinyl chloride but also a copolymer in which vinyl chloride is the main component.
Examples of the monomer compound copolymerizable with vinyl chloride include vinylidene chloride, ethylene, propylene, acrylonitrile, maleic acid, itaconic acid, acrylic acid, methacrylic acid, vinyl acetate and the like. These vinyl chloride resins may be produced by any of conventionally known production methods such as emulsion polymerization method, suspension polymerization method, solution polymerization method and bulk polymerization method.

Agricultural soft vinyl chloride resin film according to the present invention,
In order to impart excellent flexibility and mechanical strength, the plasticizer is usually added in an amount of about 20 to 60 parts by weight with respect to 100 parts by weight of the base resin.

Examples of the plasticizer include phthalic acid derivatives, isophthalic acid derivatives, adipic acid derivatives, maleic acid derivatives, citric acid derivatives, itaconic acid derivatives, oleic acid derivatives, ricinoleic acid derivatives, and other tricresyl phosphates,
Examples include epoxidized soybean oil and epoxy resin plasticizers.

Further, in order to impart flexibility to the resin film, the plasticizer is not limited to the above-mentioned plasticizer, and for example, a thermoplastic polyurethane resin, polyvinyl acetate or the like can be used.

According to the present invention, the fluorine-based surfactant compounded in the vinyl chloride resin-based agricultural coating material may be partially or wholly F instead of H bonded to C of the hydrophobic group of a normal surfactant.
Among the surfactants substituted with, a surfactant containing a perfluoroalkyl group or a perfluoroalkenyl group is particularly preferable.

Typical examples of the fluorine-based surfactant usable in the present invention are as follows.

(a) Anionic fluorosurfactant (1) -COOM type _{RfCOOM RfSO 2 N (R ')} 2 CH 2 COOM (2) -OSO 3 M type _{RfBNR'YOSO 3 M (3) -SO 3} M type RfSO ₃ M RfCH ₂ O (CH ₂ ) mSO ₃ M (4) -OPO (OM) ₂ system In each of the above formulas, Rf and R'f represent a fluoroalkyl group in which a part or all of the hydrogen atoms of the alkyl group are substituted with fluorine atoms, B represents -CO-, -SO _2- , and R'is Represents a hydrogen atom or a lower alkyl group, and Y represents C
₂ to ₆ represents an alkylene group, M is a hydrogen atom, -N
H ₄ represents an alkali metal or an alkaline earth metal, and m represents a natural number of 1 to 30.

(b) Cationic fluorinated surfactant (1) (2) In the formula, Rf, B, R ′ and Y have the same meanings as described above, R ″ represents a hydrogen atom or a lower alkyl group, HX represents an acid and X represents a halogen acid radical.

(c) Amphoteric fluorinated surfactant (1) -N (R ')₂--COO System RfBNHYN (R ')₂(CH₂) MCOO  In the formula, Rf, B, R ′, Y and m have the same meanings as described above.
It

(d) Nonionic fluorine-based surfactant (1) -OH system RfOH (2) -O- system In the formula, Rf, B, R ′ and m have the same meanings as described above.

The preferred examples of the above-mentioned type and other types of fluorine-based surfactants are as follows.

(i) CnF_{2n + 1}COOM in the formula, M = hydrogen atom, alkali metal, -NH_Four n = 5 to 12, preferably 6 to 10, for example C₉F₁₉COONa C₈F₁₇COOLi (ii) CnF_{2n + 1}CONH (C₂H_FourO) mH n = 5-12, preferably 6-10, m = 1-30, preferably 2-20, for example C₉F₁₉CONH (C₂H_FourO)₃H (iii)In the formula, R = hydrogen atom, lower alkyl group, n = 6 to 12, preferably 9, m = 2 to 30, preferably 3 to 20, for example(iv) CnF_{2n + 1}CONHC₃H₆N (CH₃)₂C₂H_FourCOO  In the formula, n = 5 to 12, preferably 6 to 10, for example C₈F₁₇CONHC₃H₆N (CH₃)₂C₂H_FourCOO  (v) CnF_{2n + 1}CONHC₃H₆N (CH₃)₃・ X  In the formula, X = halogen acid radical n = 5 to 12, preferably 6 to 10 For example, C₈F₁₇CONHC₃H₆N (CH₃)₃・ I  (vi) CnF_{2n + 1}(CH₂) mCOOM In the formula, M = hydrogen atom, alkali metal, —NH_Four n = 3 to 12, preferably 5 to 10, m = 1 to 16, preferably 2 to 10, for example C₇F₁₅(CH₂)_FiveCOONa C₈F₁₇(CH₂)_FourCOOK (vii) CnF_{2n + 1}SO₂N (C₂H_Five) C₂H_FourOPO (OH)₂ In the formula, n = 5 to 12, preferably 6 to 10, for example C₈F₁₇SO₂N (C₂H_Five) C₂H_FourOPO (OH)₂ (viii) CnF_{2n + 1}SO₂N (C₂H_Five) CH₂COOM In the formula, M = hydrogen atom, alkali metal, -NH_Four n = 5 to 12, preferably 6 to 10, for example C₈F₁₇SO₂N (C₂H_Five) CH_FiveCOOK (ix) CnF_{2n + 1}SO₂N (C₂H_Five) C₂H_FourOSO₃In the formula H, n = 5 to 12, preferably 6 to 10, for example C₈F₁₇SO₂N (C₂H_Five) C₂H_FourOSO₃H (x) CnF_{2n + 1}SO₂N (C₂H_Five) (C₂H_FourO) mH in the formula, n = 5 to 12, preferably 6 to 10, m = 1 to 30, preferably 2 to 20, for example C₈F₁₇SO₂N (C₂H_Five) (C₂H_FourO)₁₄H Each of the above-mentioned fluorosurfactants should be used alone.
Can be used, or two or more types can be used in combination.
Yes. Fluorine-based surfactant made of vinyl chloride resin for agriculture
The compounding amount (active ingredient) in the coating material is not critical,
Depending on the type of fluorosurfactant and resin to be blended
It can vary widely depending on the
100 parts by weight of the synthetic resin base material (however, the plasticizer is
Not included in the calculation. The same shall apply hereinafter) at least 0.02 parts by weight
And the upper limit of the compounding amount is strictly limited.
Not bleeding, but if added too much, bleed
It is usually 2.0 because it may cause out and cloudiness.
Less than or equal to parts by weight is sufficient.

Therefore, the preferable range of the compounding amount is the synthetic resin base material 100.
0.02 to 2.0 parts by weight, in particular 0.05 to 0.5 parts by weight, per part by weight.

In the agricultural soft film of the present invention, if necessary, a resin additive, for example, an antifogging agent, an ultraviolet absorber, a light stabilizer, an antioxidant, a lubricant, a heat stabilizer, a pigment, a colorant such as a dye, Inorganic substances, antistatic agents and the like can be added in usual amounts.

Examples of the antifogging agent include nonionic surfactants, anionic surfactants, and cationic surfactants. Of these, nonionic surfactants are preferable.

As the ultraviolet absorber, for example, benzotriazole-based,
Examples thereof include benzoate-based, benzophenone-based, cyanoacrylate-based, and phenyl salicylate-based ultraviolet absorbers. Among them, benzophenone-based UV absorbers and / or benzotriazole-based UV absorbers are particularly preferable.

As the light stabilizer, various compounds usually blended in agricultural vinyl chloride films can be used. Specifically, for example, 4-acetoxy-2,2,6,6-tetramethylpiperidine, bis (2,2,6,6-tetramethyl-4-piperidyl) adipate, tris (2,2,6,6- Tetramethyl-
Examples thereof include hindered amine compounds such as 4-piperidyl) benzene-1,3,5-tricarboxylate.

Examples of the antioxidant include 2,6-di-tert-butyl-4-methylphenol, 2,2'-methylenebis (6-tert-butyl-4-ethylphenol), dilaurylthiodipropionate and the like. You can

Examples of lubricants or heat stabilizers include polyethylene wax, liquid paraffin, bisamide, stearic acid,
Zinc stearate, aliphatic alcohol, calcium stearate, barium stearate, barium ricinoleate, dibutyltin dilaurate, dibutyltin dimalate,
Examples include organic metal phosphates, organic phosphite compounds, phenols, β-diketone compounds, and the like.

Examples of colorants include phthalocyanine blue, phthalocyanine green, Hansa yellow, alizarin lake, titanium oxide, zinc white, ultramarine blue, permanent red,
Examples thereof include quinacridone and carbon black.

Examples of the inorganic material include oxides such as calcium, magnesium and aluminum, hydroxides, carbonates, silicates and the like, and composites thereof.

These resin additives can be added in a usual content, for example, 10 parts by weight or less per 100 parts by weight of the synthetic resin base material.

The soft vinyl chloride resin film (hereinafter referred to as a base film) which is a base of the agricultural film of the present invention is, for example, a resin composition obtained by adding a necessary resin additive to a vinyl chloride resin, a ribbon blender, a Banbury. Mixer, blending machine such as a super mixer, after homogenizing with a kneading machine, a normal film manufacturing method, for example, a calendar molding method, an extrusion molding method, an inflation film molding method, etc. are adopted, and 0.01 to 0.3 mm, preferably It is molded to a thickness of 0.04 to 0.25 mm.

The antifogging agent composition for forming an antifogging coating on one surface of a base film has iricasol and / or alumina sol as a main component, and a silica or alumina binder component is mixed therein.

Silica sol and / or alumina sol has an average particle size of 5 to
The range of 100 mμ is preferable. Average particle size is 10
If it exceeds 0 mμ, the coating film tends to be white and devitrify, and if it is less than 5 mμ, the antifogging composition lacks stability, which is not preferable. These may be used alone,
Both may be used in combination. Further, when used alone or in combination of two, two or more kinds having different average particle diameters may be used in combination. When both are combined, the weight ratio of silica sol / alumina sol is 95 to 5/5 to 95.
It is preferable to set the ratio to 100 (total).

The alumina sol may be either a commercially available product itself or an aqueous sol prepared by dispersing usually commercially available alumina powder in water. Alumina sol exhibits a so-called thixotropic property that the viscosity of the dispersion rapidly increases when it is dispersed in water at a high concentration, and it is difficult to obtain a uniform dispersion, but if a medium shear internal stirrer such as a colloid mill is used. , A homogeneous dispersion can be obtained. Further, when silica sol is mixed with this dispersion, the viscosity of the dispersion can be lowered.

On the other hand, in many cases, the silica sol is negatively charged on the particle surface, but when it is used in combination with an alumina sol, it is not preferable to use a negatively charged one. This is because when silica sol and alumina sol are mixed, the mixed dispersion liquid rapidly agglomerates and gels, resulting in poor dispersion. Therefore, the colloidal silica is preferably positively charged on the particle surface.

As the binder component to be blended in the antifogging composition, known or publicly known ones such as anionic surfactants, cationic surfactants, surfactants such as nonionic surfactants or thermoplastic resins are known. used.

It is necessary to change the type of surfactant used as a binder component depending on the silica sol or alumina sol. Generally, negatively charged silica sol and cationic surfactant, positively charged alumina sol and anionic surfactant. Combinations with agents should be avoided. These combinations easily cause gelation of the sol and aggregation / separation of the antifogging agent composition, which makes application difficult.

As the thermoplastic resin used as the binder component,
Acrylic resin, vinyl chloride-vinyl acetate resin, polyethylene resin, vinyl chloride resin, vinylidene chloride resin, polyurethane resin, polycarbonate resin,
Examples include styrene-based resins, vinyl acetate-based resins, unsaturated polyester-based resins, and acrylic resins are particularly preferable.

The silica sol and / or alumina sol, which is the main component of the antifogging agent composition, is preferably compounded in an amount of 0.5 to 40 times the binder component in terms of solid content weight ratio. When it exceeds 40 times, not only the antifogging effect does not improve in proportion to the compounding amount, but also the phenomenon that the coating film formed after coating becomes cloudy and the light transmittance decreases. Further, the coating film tends to be rough and brittle. On the other hand, if it is less than 0.5 times, it becomes difficult to exert a sufficient antifogging effect.

A crosslinkable compound that crosslinks the binder components may be used in combination with the antifogging composition. By doing so, the water resistance of the anti-fog coating can be improved. As the crosslinkable compound, the same compounds used in the above-mentioned antifog coating composition can also be used in the antifog composition.
The amount of the crosslinkable compound used is preferably in the range of 0.1 to 30% by weight, more preferably 0.5 to 10% by weight, based on the solid content of the binder component.

Further, the antifog composition may, if necessary, have an antifoaming agent, a lubricant,
An antistatic agent and other various additives can be mixed.

Thus, the antifogging composition is usually used in liquid form. The liquid dispersion medium includes an affinity solvent containing water or a water-miscible solvent, and water: methyl alcohol, ethyl alcohol,
Examples include monohydric alcohols such as isopropyl alcohol: polyhydric alcohols such as ethylene glycol, diethylene glycol, and glycerin: cyclic alcohols such as benzyl alcohol: cellosolve acetates: ketones.

These may be used alone or in combination, but in consideration of the dispersion stability of the antifogging composition used in the present invention, the wettability after coating on the film surface, the difficulty of removing the liquid dispersion medium, and the economical efficiency. It is preferable to decide.

The coating of the antifogging agent composition formed on the surface of the base film generally has a solid content of 0.01 to 10 g /
It is preferably in the range of m ² , particularly 0.1 to 5 g / m ² .

In order to form a film of an antifogging composition on the surface of a substrate film, generally, a solution or dispersion of each composition is doctor blade coating method, roll coating method, dip coating method, spray coating method, rod coating method, bar coating method. A coating method known per se such as a coating method, a knife coating method and a brush coating method may be employed, and the coating may be dried after the coating. As a drying method after coating, either a natural drying method or a forced drying method may be adopted. When the forced drying method is adopted, it is usually dried at a temperature range of 50 to 250 ° C, preferably 70 to 200 ° C. Good. Any appropriate method such as a hot-air drying method, an infrared drying method, or a far-infrared drying method may be adopted for the heat drying, and the hot-air drying method is advantageous in view of the drying speed and safety.

When the adhesion between the base film and the coating derived from the coating composition is not sufficient, the surface of the base film is washed with alcohol or water in advance, or plasma discharge treatment,
Alternatively, pretreatment such as corona discharge treatment or undercoating with another paint or primer may be performed.

[Effects of the Invention] The present invention has particularly remarkable effects as follows, and its industrial utility value is extremely large.

(1) Agricultural soft vinyl chloride resin film according to the present invention, a film derived from the antifogging composition is formed on one surface of the film, so that the film surface is the inside of a house or the like. When spread, it has an excellent effect of preventing water droplets from adhering, and its antifogging effect lasts for a long period of time.

(2) Agricultural soft vinyl chloride resin film according to the present invention, a fluorine-based surfactant is blended in the substrate film, together with the coating derived from the surface antifogging agent composition, antifog effect Also, the effect lasts for a long time.

Hereinafter, the present invention will be described in detail based on Examples,
The present invention is not limited to the following examples unless it exceeds the gist.

Examples 1-5, Comparative Examples 1-2 (1) Preparation of base film Polyvinyl chloride (degree of polymerization = 1300) 100 parts by weight Dioctyl phthalate 45 〃 Tricresyl phosphate 5 〃 Epoxy resin 2 〃 Ba-Zn liquid Stabilizer 2 〃 Ba-Zn powder stabilizer 1 〃 Benzophenone UV absorber 0.1 〃 Sorbitan monopalmitate 2 〃 with the basic composition and the fluorine-based surfactant shown in Table 1 Mixed with a super mixer. The mixture was supplied to a calender molding machine heated to 100 ° C. and formed into a film by a conventional method to prepare a base film having a thickness of 0.10 mm.

(2) Formation of Film Derived from Antifog Composition An antifog composition is prepared by blending the main components (silica and / or alumina sol) shown in Table 1, a binder component, a crosslinking agent and a liquid dispersion medium. Obtained.

The above antifogging agent composition was applied to one side of the base film prepared in (1) 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. The coating amount of each film obtained was about 1 g / m ² .

(3) Evaluation of Film The performance of the soft vinyl chloride resin film for agriculture was evaluated by the following method, and the results are shown in Table 2.

Anti-fog property In a field of Isshi group in Mie prefecture, frontage 5.4m, ridge height 3m, depth 1
Six 5 m pipe houses were constructed, and eight types of films prepared were coated on each house. As a method for evaluating the drip-free property, the state in which water drops adhered to the surface of the film being spread, on which the film of the antifogging composition was formed, was visually observed with time. The evaluation standard is
It is as follows.

(Test started in October 1987) ◎ ... Water droplets adhering to the film surface (the one facing the inside of the house) coalesces and spreads in a thin film shape, and the area of this thin film portion is 1 / th of the film surface (same as above). Two or more.

O: Water droplets adhering to the film surface (same as above) are recognized, but the area of this thin film portion is less than 1/2 of the film surface (same as above).

Δ: Water droplets adhering to the film surface (same as above) are recognized, but the shape of the thin film portion is not recognized.

X: Water droplets adhering to the film surface (same as above) are not recognized as coalescing.

Anti-fog property In a field of Isshi group in Mie prefecture, frontage 5.4m, ridge height 3m, depth 1
Six 5 m pipe houses were constructed, and 8 kinds of films produced in each building were coated with the coated surface inside. As a method for evaluating the drop-free property, the state of fog generated inside the film during spreading was visually observed with time. The evaluation criteria are as follows.

(Test started in October 1987) ⊙: No fog is found in the house, but it is only slightly generated near the inner surface of the film.

○: Fog is generated in the entire house, but the inside of the house 15 m ahead can be clearly identified.

△: Fog was generated in the entire house with a little thick fog, and the inside of the house 15 m ahead could not be identified.

×: The fog was heavily generated in the entire house and the inside of the house 15 m ahead could not be identified at all.

The following is clear from Table 2.

(1) Comparative Example 1 is excellent in antifogging property, but is insufficient in fog resistance.

(2) Comparative Example 2 is inferior in antifogging property. In addition, the fog resistance is good at the initial stage, but thereafter decreases and the fog resistance persistence is insufficient.

(3) Contrary to this, the agricultural soft vinyl chloride resin film of the present invention (Examples 1 to 5) is excellent in antifogging property and antifog property even when used for a long period of time.

Claims (1)

[Claims] 1. A soft vinyl chloride resin film containing a fluorosurfactant, on one side of which a coating derived from an antifogging composition mainly composed of silica sol and / or alumina sol and a binder is formed. A soft vinyl chloride resin film for agriculture characterized by.