JPH0583207B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to agricultural vinyl chloride resin films,
In particular, the present invention relates to an agricultural vinyl chloride resin film that has excellent antifogging properties and antifogging durability at low temperatures, and also has excellent water aggregation ability to prevent high humidity in greenhouses. [Prior Art] In recent years, greenhouse horticulture has been on the rise due to its ability to increase profits through forced cultivation or controlled cultivation of useful plants. The covering materials used for this greenhouse horticulture include:
Polyethylene film, ethylene-vinyl acetate copolymer film, polycarbonate film, methyl methacrylate resin film, acrylic resin film, vinyl chloride resin film, glass, etc. are used. Among them, agricultural vinyl chloride resin films containing a large amount of plasticizer are widely used because they have superior light transmittance, heat retention, mechanical strength, and weather resistance compared to other synthetic resin films. . By the way, since the surface of a vinyl chloride resin film is hydrophobic, when it is spread in a house, water vapor generated inside the house becomes water droplets and condenses on the inner surface of the film. Therefore, the condensed water droplets not only significantly reduce light transmission and block sunlight from irradiating the cultivated crops, but also fall onto the cultivated crops and may cause damage to the crops. Furthermore, since condensation of moisture inside the greenhouse relies solely on the effect of the antifogging agent, the interior of the greenhouse tends to become humid, and in some cases, there is a risk of disease. Conventionally, in order to solve this problem, we imparted hydrophilicity to vinyl chloride resin so that the water droplets that condensed on the surface flowed down while uniformly wetting it, in order to prevent the occurrence of fogging due to dew condensation on the inner surface of the film. Antifogging agents have been blended into vinyl chloride resin compositions before film molding. Antifogging agents generally include sorbitan surfactants such as sorbitan monostearate, sorbitan monopalmitate, and sorbitan monobenzoate, and glycerin surfactants such as glycerin monolaurate, diglycerin monopalmitate, and glycerin monostearate. Polyethylene glycol surfactants such as polyethylene glycol monostearate and polyethylene glycol monopalmitate, and esters of sorbitan and glycerin condensates with organic acids are known.
Further, these surfactants are used alone or in combination of two or more. However, although such commonly used antifogging agents have normal antifogging properties at low temperatures, their antifogging properties at low temperatures are insufficient when used in regions with severe winter temperatures. In order to further improve hydrophilicity and speed up the run-off time of condensed water, surfactants with alkylene oxide, especially ethylene oxide added to the above surfactants are often used to address these problems, but performance improvements at low temperatures are still insufficient. Furthermore, since the hydrophilicity was improved, the long-lasting effect as an antifogging agent was reduced. To deal with this, it is possible to have a lasting effect by increasing the amount of antifogging agent added, but if a large amount of antifogging agent is used, the antifogging agent will bleed over time and the film will become sticky. Furthermore, there was a problem that the film itself became white. Therefore, the technology to improve the coagulation ability of moisture within the greenhouse still remains an issue. Based on the above, a film that has the three properties required for film properties to maintain a good greenhouse environment: an antifogging agent at low temperatures, antifogging persistence, and water aggregation ability has not yet been found. do not have. [Problems to be Solved by the Invention] The object of the present invention is to provide an agricultural vinyl chloride resin film that has excellent antifogging properties at low temperatures and long-lasting properties, as well as excellent moisture aggregation ability and prevents high humidity inside greenhouses. It's true. [Means for Solving the Problems] In order to achieve the above object, the present inventors made extensive studies and found that an alkylene oxide adduct of a nonylphenol/formalin condensate and a sorbitan ester are used together in a specific weight ratio, Moreover, the number of carbon atoms is 3 to 20
We discovered that by blending a specific amount of a compound with a polyfluoroalkyl group, it is possible to obtain an agricultural vinyl chloride resin film that has excellent low-temperature antifogging agents, long-lasting antifogging effects, and water coagulation ability. This led to an invention. That is, the present invention uses 0.5 to 4 parts by weight of a mixture of a compound obtained by adding 1 to 30 moles of alkylene oxide to a nonylphenol formalin condensate and a sorbitan ester, and 3 to 3 carbon atoms, to 100 parts by weight of a vinyl chloride resin. It contains 0.01 to 2 parts by weight of a compound having 20 polyfluoroalkyl groups, and the mixing ratio of the alkylene oxide adduct of the nonylphenol formalin condensate and the sorbitan ester is 1/9 to 5/5 by weight. This is an agricultural vinyl chloride resin film characterized by the following. Examples of the vinyl chloride resin used in the present invention include not only polyvinyl chloride but also copolymers containing vinyl chloride as a main component. Examples of monomers that can be copolymerized with vinyl chloride include vinylidene chloride, ethylene, propylene, acrylonitrile, vinyl acetate, maleic acid, itaconic acid, acrylic acid, and methacrylic acid. In the present invention, a mixture of an alkylene oxide adduct of a nonylphenol/formalin condensate and a sorbitan ester is used. The nonylphenol-formalin condensate, which is the raw material for the compound in which alkylene oxide is added to the nonylphenol-formalin condensate, which is the active ingredient of the present invention, can be prepared using known techniques such as mixing nonylphenol and formalin in a solvent with an acid or alkali. It can be obtained by heating and condensing in the presence of a catalyst. The degree of condensation is preferably 2 to 10, and those having a degree of condensation of 3 to 7 are particularly preferable from the viewpoint of long-lasting performance of the antifogging agent. Note that the degree of condensation corresponds to the number of nonylphenols in one condensate. Furthermore, the alkylene oxide adduct of a nonylphenol/formalin condensate is one in which ethylene oxide and/or propylene oxide is added to the formalin condensate. The addition of alkylene oxide to the nonylphenol-formalin condensate is carried out using known techniques, for example, by reacting the condensate with alkylene oxide under heating in the presence of an alkali catalyst. The addition rate of alkylene oxide is preferably 1 to 30 moles when only ethylene oxide is added. In particular, when the addition rate is 1 to 15 mol, the antifogging effect is long-lasting. The effective antifogging agent composition in the present invention is a mixture of 1 to 30 moles of alkylene oxide adduct of the nonylphenol/formalin condensate and sorbitan ester. As the sorbitan ester, sorbitan stearate or sorbitan palmitate is preferred. Esters of fatty acids with less than 15 carbon atoms have good initial effects but lack sustainability, while esters of fatty acids with more than 19 carbon atoms have good sustainability but have poor initial effects. The mixing ratio of the alkylene oxide adduct of the nonylphenol formalin condensate and the sorbitan ester is preferably 1/9 to 5/5, more preferably 2/8 to 4/6. If it is smaller than 1/9, the initial effect will be inferior, and if it is larger than 5/5, the sustained effect will be inferior. The amount of the antifogging agent mixture above is based on vinyl chloride resin.
The amount is preferably 0.5 to 4 parts by weight, more preferably 1 to 3 parts by weight per 100 parts by weight. Addition amount is 0.5
If the amount is less than parts by weight, the antifogging performance will be poor, which is not preferable. On the other hand, if the amount is more than 4 parts by weight, the film tends to become sticky or white due to bleeding, resulting in a decrease in commercial value. In the present invention, a compound having a polyfluoroalkyl group having 3 to 20 carbon atoms is used in combination. Examples of such fluorine compounds include compounds represented by the following general formula. (1) R _f BF In this formula, R _f represents a polyfluoroalkyl group having 3 to 20 carbon atoms, and B represents -CO- or -SO ₂ -. These R _f and B have the same meaning in the following general formula. (2) R _f OH (3)

[C] In this formula, R ¹ represents −C ₂ H ₄ −, −C ₃ H ₆ −, and R ²
represents a hydrogen atom or a lower alkyl group, and n is 1 to
Represents an integer of 30. Moreover, these R ¹ and R ² have the same meaning in the following general formula. (Four)

[ka] In this formula, a represents an integer from 1 to 100. (Five)

[Image Omitted] In this formula, b represents an integer of 1 to 40, and c represents an integer of 1 to 100. b and c have the same meaning in the following general formula. (6)

[C] In this formula, R ³ is a hydrogen atom or a methyl group,
Q is a difunctional organic group, W is -COO- or -
Represents CH ₂ O−. R ³ , Q and W have the same meanings in the following general formulas. (7)

[Chemical formula] (8) R _f COOM In this formula, M represents a hydrogen atom, an alkali metal, an alkaline earth metal, or NH ₄ ⁺ . M has the same meaning in the following general formulas. (9)

[Chemical formula] (10) R _f SO ₃ M (11) R _f CH ₂ OC _n H _2n SO ₃ M In this formula, m represents an integer from 1 to 20. m has the same meaning in the following general formulas. (12)

[ka] (13)

[ka] (14)

[ka] In this formula, HX represents a halogen acid. (15)

embedded image In this formula, X represents a halogen acid group. The following general formulas also have the same meaning. (16)

[ka] (17)

〔Example〕

The present invention will be explained below with reference to Examples. Examples 1 to 6, Comparative Examples 1 to 7 Antifogging agents and fluorine compounds of the type and amount shown in Table 2 were added to the basic formulation shown in Table 1 below, mixed for 10 minutes with a Henschel mixer, and 165 After roll-kneading at ℃, an agricultural vinyl chloride resin film (hereinafter abbreviated as agricultural vinyl) having a thickness of 0.10 mm was obtained using an L-type calender.

【table】

〔Effect of the invention〕

As is clear from the above examples, the film of the present invention uses the antifogging agent and fluorine compound of the present invention in combination, and has better protection at low temperatures than the film that uses the conventional antifogging agent and fluorine compound in combination. Clouding effect (flow start time,
It has good surface condition) and durability, and also has excellent water coagulation ability. On the other hand, when a fluorine compound is not used in combination, a large difference in water aggregation ability is observed, resulting in poor fog-proofing properties. When the amount of the antifogging agent of the present invention added exceeds 4 parts by weight, low-temperature antifogging properties, surface condition, and durability are good, but a blowout phenomenon tends to occur. Furthermore, if the amount of the antifogging agent of the present invention added is less than 0.5 part by weight, the antifogging performance will be poor. The agricultural vinyl chloride resin film according to the present invention has the following effects and greatly contributes to greenhouse horticulture. Since it has good anti-fog properties at low temperatures, it can exhibit sufficient anti-fog effects even in extremely cold regions. Because of its high water aggregation ability, it can prevent the inside of the greenhouse from becoming too humid and can also reduce the occurrence of diseases that occur in crops in humid environments. Since it has a good anti-fog effect, it is possible to secure a sufficient amount of light even in the winter when there are few hours of sunlight, creating a favorable environment for crop cultivation. Because of its good sustainability, it can prevent water droplets from falling over a long period of time, and it can also ensure a sufficient amount of light until the crop is harvested, so it can be expected to improve the quality and yield of crops. Since the inner surface is in good condition, a uniform beam of light can be obtained, and the inside of the house can be easily observed from the outside.

Claims (1)

[Scope of Claims] 1. 100 parts by weight of a vinyl chloride resin, 0.5 to 4 parts by weight of a mixture of a compound obtained by adding 1 to 30 moles of alkylene oxide to a nonylphenol formalin condensate and a sorbitan ester, and the number of carbon atoms. It contains 0.01 to 2 parts by weight of a compound containing 3 to 20 polyfluoroalkyl groups, and the mixing ratio of the alkylene oxide adduct of the nonylphenol formalin condensate and the sorbitan ester is 1/9 to 1/9 by weight. An agricultural vinyl chloride resin film characterized by a 5/5 ratio. 2. The agricultural vinyl chloride resin film according to claim 1, wherein the alkylene oxide is ethylene oxide and/or propylene oxide. 3. The agricultural vinyl chloride resin film according to claim 1, wherein the sorbitan ester is sorbitan stearate and/or sorbitan palmitate.