JPH04180942A - Antifog agent for synthetic resin covering material for agricultural use - Google Patents

Abstract

PURPOSE:To prepare the title material having antifog properties by incorporating a specific fluorinated phosphoric ester into the material. CONSTITUTION:A reaction product of a polyfluoroalkylated alcohol with phosphoryl chloride is reacted with a compd. contg. ethylene oxide to give an antifog agent comprising a fluorinated phosphoric ester of formula I (wherein A is a residue of a dihydric or higher alcohol; B is a divalent org. group; R1 and R2 are each H or CH3 provided that they are not simultaneously CH3; R3 is H, alkyl, or a group of formula II; and R4 is H or alkyl) having polyfluoroalkyl groups, polyoxyethylene groups, and phosphoric ester groups. A resin compsn. comprising a base resin, pref. PVC, if necessary compounded with a plasticizer, a lubricant, a thermal stabilizer, a pigment, etc., is compounded with at least 0.01 pts.wt. (based on 100 pts.wt. the resin) the agent to give the title material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an anti-fog and anti-fog agent for agricultural synthetic resin coating materials. More specifically, the present invention relates to a compound that independently imparts antifogging properties and antifogging properties.

[Prior Art] In recent years, crop cultivation in greenhouses and tunnels has been widely practiced for the purpose of forced cultivation and out-of-season cultivation of agricultural and horticultural crops. Plastic films such as polyethylene film and polyvinyl chloride film are used as covering materials for these facilities, and the latter is mainly used because of its excellent light transmittance, heat retention, and weather resistance. .

However, since the surface of a polyvinyl chloride resin film is hydrophobic, water vapor condenses on the film when it is stretched, covering the surface and causing cloudiness. This not only reduces the transmittance of sunlight but also causes problems such as damage to crops due to falling water droplets. Conventionally, a method for solving such problems has been to add an antifogging agent (for example, sorbitan fatty acid ester, glycerin fatty acid ester) to vinyl chloride resin to impart hydrophilicity. As a result, the condensed water droplets are diffused onto the film surface, uniformly wetting the film, and flowing down, so that the surface can be maintained in a transparent state.

However, under a coating material containing such an antifogging agent, the temperature difference between the inside and outside of the coating material becomes large, so that a phenomenon in which fog is generated near the inner surface of the coating material is often observed. The causes of this fog phenomenon, which often occurs from late autumn to winter, are not clear, but include the temperature and humidity inside the greenhouse or tunnel, the temperature and moisture content of the soil inside the greenhouse or tunnel, the amount of solar radiation into the greenhouse or tunnel, The degree of hydrophilicity on the inside of the sheathing material subtly influences each other, so that the moisture inside the house or tunnel smoothly adheres to the surface of the sheathing material due to temperature changes, and the phenomenon in which it does not flow away occurs, and some moisture is removed. It is presumed that this is due to dew forming near the inner surface of the coating material.

In order to suppress such fog generation phenomenon, Japanese Unexamined Patent Publication No. 55-9
There have been proposals for adding organic siloxane surfactants as described in JP-A No. 1663 and fluorine-based surfactants as described in JP-A-57-14648 into the film, but none of them are effective in suppressing fog generation. However, there are disadvantages in that the antifogging effect is insufficient, and even if it has an antifogging effect, the antifogging effect is not exhibited unless it is used in combination with other antifogging agents.

[Problems to be Solved by the Invention] Therefore, the present invention adds a single compound to prevent the generation of fog in agricultural greenhouses (fog-proofing properties) and to prevent fogging of vinyl films (anti-fogging properties). This invention relates to an effective anti-fog and anti-fog agent for synthetic resins.

[Means for Solving the Problems] The present inventors provide an agricultural synthetic resin coating material that has both anti-fog and anti-fog properties by adding a single compound as described above. As a result of research aimed at this purpose, it was discovered that a special fluorine-containing compound whose structure is completely different from those proposed in the past is extremely effective, leading to the completion of the present invention.

That is, the present invention improves conventional antifogging by adding at least one kind of fluorine-containing phosphate ester compound having a polyfluoroalkyl group, a polyoxyalkylene group, and a phosphate bond represented by the following general formula [I]. It has become possible to impart anti-fog and fog-proof properties to agricultural synthetic resin coating materials without using any additives.

...... [1] However, in the above general formula, A is a polyhydric alcohol residue with a valence of 2 or more, B is an organic group with a valence of 2 or more, and R1 and R2 are a hydrogen atom or a methyl group (however, R1, R8 is a hydrogen atom or an alkyl group, or @R, (R is a hydrogen atom or an alkyl group).

Further, 11 and n% a, p and q are integers of 1 or more, a+b is the valence of the polyhydric alcohol, and p+q=3. Rf represents a polyfluoroalkyl group having 1 to 2 carbon atoms.

Specific examples of the fluorine-containing phosphate ester compound represented by the general formula [I] of the present invention include the following.

CaF + ycJ40P [0(CJ-0) x +
C+ 2Hzal tC,,Fa,,-+CJ40P[
0(C2H40)i. (C-HsO4)C+ 5H-s
l xC,, F2. ,Ya, C2H40 payment [0 (C mountain Q)
,, @CaHl-] 2 The method for synthesizing the compound represented by the general formula [I] is not limited at all, but it can be produced as follows. That is, alcohols containing polyfluoroalkyl groups (for example, CaF, , C, H, OH, C, F, , CH, OH, etc.)
By reacting phosphorus oxychloride and the reactant with an ethylene oxide-containing compound (for example, a polyhydric alcohol such as glycerin or ethylene glycol with ethylene oxide or propylene oxide alone or in a mixture), the desired A fluorine-containing phosphate ester compound can be obtained. The fluorine-containing phosphate ester compound obtained above can exhibit the desired antifogging performance and antifog performance, either alone or in combination of two or more.

The synthetic resin material constituting the agricultural synthetic resin coating material of the present invention generally includes film-forming thermoplastic synthetic resins. Specifically, homopolymers of monomers such as vinyl chloride, ethylene, propylene, acrylic esters, methacrylic esters, copolymers of these monomers, or copolymers of at least one of these monomers with other monomers. Examples include copolymers with possible monomers (eg, vinyl acetate, vinylidene chloride, etc.), fluorine-containing resins, polyesters, polyamides, etc., or blends of these polymers. Among these, vinyl chloride resins and ethylene resins are preferred from the viewpoints of weather resistance, light transmittance, economic efficiency, and strength, and polyvinyl chloride is most advantageous.

The amount of the fluorine-containing phosphate ester compound added to the synthetic resin coating material in the present invention can be varied over a wide range depending on the type of the fluorine-containing phosphate ester compound to be blended, the type of the base synthetic resin, etc. - For boat fishing, base synthetic resin 1
The amount can be at least 0.01 part by weight per 00 parts by weight (excluding compounding agents such as plasticizers, anti-fogging agents, stabilizers, etc.), and the upper limit of the amount to be blended is strictly limited. However, if too much is added, there is a risk of bleed-out or clouding, so it is usually 2.0.
Parts by weight or less are sufficient. The preferred range of blending amount is 0.02 to 1.0 parts by weight per 100 parts by weight of the base synthetic resin.

The synthetic resin base material constituting the agricultural covering material according to the present invention may also contain various conventional additives, such as plasticizers, lubricants, heat stabilizers, antistatic agents, ultraviolet absorbers, pigments,
Dyes and the like can be included in conventional amounts.

For example, regarding the soft vinyl chloride resin suitable for the present invention, 30 to 70 parts by weight of a plasticizer can be blended with 100 parts by weight of polyvinyl chloride having a degree of polymerization of 1000 to 2000.

Suitable plasticizers that can be used include phthalic acid derivatives such as di-n-octyl phthalate, di-2-ethylhexyl phthalate, dibenzyl phthalate, diisodecyl phthalate, didodecyl phthalate, and diisodecyl phthalate, di-n-butyl adipate, Adipic acid derivatives such as dioctyl adipate, maleic acid derivatives such as di-n-butyl maleate, citric acid derivatives such as tri-n-butyl citrate, itaconic acid derivatives such as monobutyl itaconate, oleic acid derivatives such as butyl oleate, etc. Examples include tricresyl phosphate, epoxidized soybean oil, and epoxy resin plasticizers.

Examples of the lubricant and heat stabilizer contained in the synthetic resin base material include polyethylene wax, bisamide, stearic acid, zinc stearate, barium stearate, calcium stearate, and barium ricinoleate. Examples of the ultraviolet absorber include benzotriazole-based, benzoate-based, benzophenone-based, cyanoacrylate-based, and phenylsalicylate-based ultraviolet absorbers. Examples of pigments and dyes include titanium oxide, silica, ultramarine blue, and phthalocyanine blue.

These resin additives are contained in a usual amount, for example, in a small amount of 5 parts by weight or less per 100 parts by weight of the synthetic resin base material.

In order to incorporate various resin additives such as fluorine-containing urethane compounds into the synthetic resin that serves as the base material, ordinary compounding techniques, mixing techniques,
For example, this can be done by mixing with a ribbon blender, Banbury mixer, super mixer, or other blender or mixer, and then forming the mixture into a film.

To form a synthetic resin into a film, methods known per se,
For example, a melt extrusion method, a solution casting method, a calender method, etc. may be employed.

If the thickness of the agricultural synthetic resin covering material according to the present invention is too thin, the strength will be insufficient, which is undesirable.On the other hand, if it is too thick, it will be difficult to form a film, and the subsequent handling (cutting the film and joining it into a house shape) 0.0. O1~0.5
It is preferable to set it in the range of mm.

[Example] Below, production examples and examples of the fluorine-containing urethane compound having a polyfluoroalkyl group, a polyoxyalkylene group, and a phosphoric acid ester bond of the present invention are shown.

<Production Example 1> Put 3.1 g (0.02 mol) of phosphorus oxychloride into a 100 ml four-loaf flask, and add dehydrated C from a dropping funnel with a side pipe while flowing dry nitrogen at 80°C.
30% of nF211++CJ40H (n=6.8, 10, 12°14, 16 mixture, average molecular weight 514).

34.3 g of 1.4-dioxane solution was added dropwise over 2 hours. It was confirmed by gas chromatography that the reaction rate of C1Fa-++CJ40H reached 100% one hour after the dropwise addition. Subsequently, dehydrated HO (CJ40) g. (cao
go) 4C-+5Hsz (Nippon Surfactant Co., Ltd. PBC-34) 54.2 g (0.4 mol) was added, 8
The reaction was carried out at 0°C for 20 hours, and the end of the reaction was determined by confirming that no hydrochloric acid gas was generated. 1,4-dioxane, the reaction solvent, was distilled off under reduced pressure, and the fluorine-containing phosphoric acid 66.2 g of an ester compound was obtained (yield 98%) <Production Example 2> 3.1 g (0.02 mol) of phosphorus oxychloride was placed in a 200 ml four-necked flask, and dried nitrogen was added at 80°C. While flowing, add dehydrated C from the dropping funnel with a side pipe.
, F,, C, 30.9 g of a 30% 1,4-dioxane solution of H40H was added dropwise over 2 hours. It was confirmed by gas chromatography that the reaction rate of C5F1tcJ40H reached 100% one hour after the dropwise addition.

Next, 1 mole of dehydrated glycerin was added with ethylene oxide and propylene oxide in a ratio of 80:20 (weight ratio) to give 140 g of polyol with a molecular weight of 3500 (
0.04 mol) was added, and the reaction was carried out at 80° C. for 20 hours, and it was confirmed that no hydrochloric acid gas was generated, which was the end point of the reaction. The reaction solvent 1,4-dioxane was distilled off under reduced pressure to obtain 147.8 g of a fluorine-containing phosphate ester compound. (
Yield 97%) <Example> Several types of fluorine-containing phosphate ester compounds having a polyfluoroalkyl group, a polyoxyalkylene group, and a phosphate ester bond were produced by the method shown in the production example, and these were added. A synthetic resin film was prepared and evaluated.

Film composition Polyvinyl chloride (degree of polymerization = 1300) 100 parts by weight Dioctyl phthalate 45 Tricresyl phosphate 3 Ba-Zn liquid stabilizer
2 Ba-Zn powder stabilizer 1
Horn-containing urethane compound 1 A mixture having the above composition was kneaded at 160 to 170°C to prepare a film with a thickness of about 150 microns.

◇Anti-fog evaluation 150ml of 75°C warm water to 300ml in a room at 25°C
Place it in a beaker and seal the opening of the beaker with the film mentioned above. Observe the surface condition of the inner surface of the film after 5 minutes have elapsed. The evaluation criteria were the following five levels.

1. Water adheres to the film surface in the form of a film.

2. There are large water droplets in some parts.

3. There are large and small water droplets, but there are also film-like parts.

4. Large and small water droplets are present, and there is no film-like part.

5. - Small water droplets adhere to the surface and the bottom of the beaker cannot be seen.

◇ Fog-proof evaluation A fog observation box with wooden boards on all sides, the water surface of an aquarium on the bottom, and a sloping ceiling covered with a test film was left on top of an aquarium with a water temperature of 40°C at a room temperature of 25°C for 48 hours. do. Water temperature 40℃
The room temperature was lowered to 5° C. while maintaining the temperature at 5° C., and after 1 hour, the state of fog generation near the film surface on the water tank side was visually observed.

The evaluation criteria were the following four levels.

A. It's stuck (no fog is observed).

B: A very small amount of fog was observed.

Occurrence of C2 fog is observed.

D: An extremely large amount of fog is observed.

[Effects of the Invention] The agricultural synthetic resin coating material containing the antifogging and antifogging agent according to the present invention exhibits the following remarkable effects, and its industrial utility value is extremely large.

The present invention has performance that conventional additives cannot achieve.

That is, by adding a single compound (without adding a general-purpose antifogging agent), excellent antifogging and fogproofing properties can be imparted to agricultural synthetic resin coating materials.

Procedural amendment December 2-1, 1990

Claims (1)

[Claims] (1) For synthetic resin coating materials for agriculture, characterized in that the active ingredient is a fluorine-containing phosphate ester compound represented by the following general formula [I] having a polyfluoroalkyl group, a polyoxyalkylene group, and a urethane bond. Anti-fog anti-fog agent. ...[I] However, in the above general formula, A is a polyhydric alcohol residue with a valence of 2 or more, B is an organic group with a valence of 2 or more, and R_1 and R_2 are hydrogen atoms or methyl groups (however, R_1, Both of R_2 are methyl groups), R_3 is a hydrogen atom or an alkyl group, or ▲a numerical formula, chemical formula, table, etc.▼(R_4 is a hydrogen atom or an alkyl group). Further, m and n, a and b, p and q are integers of 1 or more, a+b is the valence of the polyhydric alcohol, and p+q=3. Rf represents a polyfluoroalkyl group having 1 to 20 carbon atoms.