JPS58103533A - Improvement of durability of antifogging property of antifogging film - Google Patents

Abstract

PURPOSE:To improve greatly the durability of antifogging property of the surface not coated with a paint, by coating one surface of an antifogging film with an ultraviolet ray-curable paint and curing the film by ultraviolet ray irradiation. CONSTITUTION:One surface of an antifogging film prepared from a thermoplastic resin (e.g., vinyl chloride polymer) film and an antifogging film (e.g., partial ester derived from a polyhydric alcohol, such as sorbitan, and a 12-22 C fatty acid) is coated with an ultraviolet ray-curable paint (e.g., a mixture of an epoxy group-containing monomer and/or polymer mixed with a photosensitive aryldiazonium compound so as to form a film, 0.5-10mu thick. Then, this film is irradiated with ultraviolet rays to improve the durability of the antifogging property of the surface not coated with the above paint.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for improving the anti-fog durability of an anti-fog film.

Thermoplastic resin films, especially polyvinyl chloride films, are often used for greenhouses, but anti-fog treatment has been applied to prevent the interior surfaces of the films from fogging up and from getting wet. This is to prevent the transmittance of sunlight and to prevent water droplets attached to human blood from falling onto the cultivated crops and damaging them. For the antifogging treatment, a method is used in which a film is coated with an antifogging agent such as a sorbitan ester, or a film is made of a polymer mixed with an antifogging agent. The outdoor surface of the greenhouse film covered with such an anti-fog film is often exposed to wind and rain, and the indoor surface is constantly wet with water, so the anti-fog agent evaporates from the film to a large extent. The durability of the antifogging performance of the film was low.

As a method to improve this drawback, there is a method of applying acrylic resin paint to one side of the anti-fog film.
This is proposed in Publication No. 91. However, the acrylic resin itself does not have great barrier properties against antifogging agents and hazy agents, and since a solvent is used during coating, the antifogging agents and hazy agents eluted are contained in the acrylic resin coating. , because it activates the subsequent migration of anti-fog agents and plasticizers from the lower anti-fog film layer, the anti-fog performance decreases over time, and the anti-fog performance usually decreases in the middle of the season. There was a problem.

Of course, methods have been proposed such as using a solvent for acrylic resin paint that does not dissolve vinyl chloride or using an aqueous dispersion of acrylic resin as a paint, but these methods limit the amount of acrylic resin used. However, it has various problems.

In view of the above, the present inventors have conducted intensive research on a method for improving the anti-fog durability of an anti-fog film that lasts for at least one season. , an anti-fog film characterized in that an ultraviolet curable coating is coated on one side of the anti-fog film to a thickness of as;-ioμ and cured by ultraviolet irradiation to improve the anti-fogging durability of the non-coated side of the coating. The present invention relates to a method for improving the anti-fog durability of the invention.

Ultraviolet curable paints can be applied without using a lot of solvents, so there is very little chance that the antifogging agent or plasticizing agent in the antifogging film will enter the coating layer. Since the antifogging agent and plasticizer hardly seep out from the film, and the barrier effect of the coating itself is very good, it is thought that the antifogging durability is greatly improved. UV-curable paints include acrylic (including acrylic modified urethane, acrylic modified polyester, and acrylic modified epoxy),
There are polythiol-based and epoxy-based paints. Among these, epoxy-based and polythiol-based ultraviolet curing paints are preferred, and epoxy-based paints are particularly preferably used.

Although a thermoplastic resin film can be used as the film base material for the antifogging film of the present invention, a vinyl chloride polymer film is most commonly used in terms of cost, transparency, weather resistance, and other performance considerations. Vinyl chloride-based polymers include divinyl chloride, copolymers of vinyl chloride and other monomers such as ethylene, vinyl acetate, vinyl ether, maleic acid ester, etc., and these polymers with each other or with other polymers. Includes blends of. For these polymers, plasticizers to impart appropriate flexibility and extensibility to the film, other lubricants, stabilizers, UV II @ collectors,
It goes without saying that antioxidants, pigments, inorganic substances, antistatic agents, etc. can be contained.

In the present invention, all kinds of antifogging agents, whether known or new, can be used, and the type is not specified in any way, but (2) oxyethylene alkyl ether, Ether types such as lyoxyethylene alkylaryl ether and polyoxyethylene polyoxypropylene ether, ester types such as Tagiri oxyethylene alkyl ester, partial esterification products of polyhydric alcohol and fatty acid, etc., 0 polyoxyethylene alkyl Aminoether type products such as Arun, ■Polyoxyethylene sorbitan fatty acid ester, l-lyoxyethylene sorbitol fatty acid ester, merioxyethylene mannitane fatty acid ester, polyoxyethylene glyceryl fatty acid ester, merioxyethylene propylene glycol Examples include ether ester types such as monofatty i1 ester. These antifogging agents can basically be selected arbitrarily, but preferably they have properties such as moldability, heat resistance, transparency, etc. in addition to maintaining antifogging properties, and are suitable for agricultural use. It is desirable that the performance as a coating material be fully satisfied. Examples of suitable antifogging agents for obtaining the above performance include (+) polyhydric alcohols such as sorbitan, sorbitol, manethane, mannitol, glycerin, and diglycerin, and partial esters of fatty acids with carbon atoms of 7λ to 11 ) The number of moles of ethylene oxide or propylene oxide added is /-20, the polyhydric alcohol is sorbitan, sorbitol, manethane, glycerin, diglycerin, and the number of carbon atoms of the fatty acid is /corcoco g IJ
Examples include mixtures of oxyalkylene polyhydric alcohol fatty acid esters (1) (1)<II).

These antifogging agents are added in an amount of at least 0.3 parts by weight, preferably in a range of 10 to 10 parts by weight, per 100 parts by weight of the vinyl chloride resin. If the amount added is less than 3 parts by weight, a sufficient antifogging effect cannot be obtained, and! If the weight exceeds .

These antifogging agents may be applied to a base film, or may be mixed with a polymer to form a film.

The latter is common as an anti-fog film.

The epoxy-based ultraviolet curable paint used in the present invention is, for example, a mixture of a heptamine and/or resin having an epoxy group and a photosensitive aryldiazonium compound.

The epoxy resin monomer has an oxy ring represented by the following structural formula.

Specific examples of the above-mentioned monomers include, for example, ethylene oxide and their homologs, glycidic acid and glycidyl esters, glycidyl methacrylate, acrylate, and crotonate, and allyl glycidyl ether.

Further, the epoxy resin low polymer is preferably a low polymer of the above-mentioned monomers, has a solubility capable of dissolving the film f1 side by 11%, and is liquid at room temperature.

The photosensitive aryldiazonium compound used in the present invention is represented by the following structural formula.

(In the formula, MX is a complex containing a halogen selected from hexachlorostannate N1, tetrachloro heptanate 11 hexafluoroalkeptate, hexachloroantimonate, hexafluoroantimonate, and bismuth monochloride) is an anion, and Y is selected from the group consisting of nitro, halogen, N-morpholino, alkyl, alkoxy, aryl, amino, arylamino, alkyla), and arylmercapto groups.

Furthermore, m corresponds to the number of Lewis halogen atoms generated upon exposure to ultraviolet rays, that is, the charge of the complex cation. ) When the aryldiazonium compound is exposed to ultraviolet light 11, it forms a Lewis Im! of the general formula MX. (i.e.,
PF island, FlC13s As Fl, 5nct4
and B1C1g, etc.), and the Lewis layer initiates polymerization of the epoxy resin monomer and/or its low polymer.

Specific examples of the aryl diazonium compounds include p-methoxybenzenediazonium hexafluorophosphate, 0-2) O-benzenediazonium hexafluorophosphate, J, j-diku-p-brobenzenediazonium hexafluorophos-7ate, co, Diazonium hexafluorophosphate such as j-jetoxy-'I-p-)rimercaptobenzenediazonium hexafluorophosphate, p-N-morpholinophenyldiazonium hexafluorophosphate, 21j-dimethoxy-41-N-morpholinobenzenediazonium hexafluorophosphate, etc. Fluorophosphate, p-N-morpholinophenyldiazonium hexafluoroantimonate, p-N
-morpholino phenyldiazonium hexafluorophosphate and other N-morpholino complexes.

&9 As a thiol-based ultraviolet curing paint, Tokko Shoda 7
-3269, JP-A No. 53-134096, etc., a sensitizer is added to polyene and/or polyol and polythiol, and it is cured by ultraviolet irradiation, and is flexible. Can be used.

Acrylic UV-curable paints are mainly composed of compounds with acrylic or methacrylic groups at the end, and oligomers such as acrylic-modified urethane, acrylic-modified epoxy 1, and acrylic-modified polyester can be used, and hardness and degree of crosslinking can be adjusted. Therefore, various acrylic thread picks can be used.

The average thickness of the coating film of the above ultraviolet hardening and thermosetting paint is 0.3 to 1.
Preferably, it is 0μ. If the average thickness is less than 0.5 mm, the effect of improving the durability of lock protection is insufficient, and if it exceeds 10 μ, the elongation of the coated film decreases, which is not preferable.

Examples are shown below.

EXAMPLES AND COMPARATIVE EXAMPLES A composition having the following formulation was calendered to prepare a protective film having a thickness of Q/- (referred to as film F/).

Polyvinyl chloride 100 (
parts by weight) plasticizers (DOP (da, t), TCP (j)
) ') J O stabilizer Addition of dasorbitan monostearate with EO coco l sorbitan monopalmitate I lubricant
Agent Oko (Note 7) Ko): DOP+7O dioctyl ester, TCP
: ) Liclesyl phos 7ate.

EO: ethylene oxide) Azoka Ultraset "7200" on one side of film F/
(manufactured by Asahi Denka α, epoxy ultraviolet curing paint) about 3μ
The film was coated to a thickness of , and cured by irradiation with ultraviolet rays (referred to as film F-).

Polythiol-based ultraviolet 4I curable paint #coJ//B manufactured by W,L Grace was applied to one side of Film F/ to a thickness of approximately 3μ, and cured by UV irradiation (Film F3
).

Approximately 3μ of Conidic V-1i60/C Dainippon Ink (made by Dainippon Ink, acrylic UV curing paint) was applied to one side of the film F/.
The film was coated to a thickness of 1, and cured by irradiation with ultraviolet rays (referred to as film Fda).

A 3% solution of Dianal BR-60 (Mitsubishi Rayon Kyoku, acrylic resin) was applied to one side of Film F/ and dried to form a coating film with a thickness of about 3 μm (referred to as Film Fj).

A small house was made using the above J film and its anti-fogging ability was evaluated for 11 years. The results are shown in Table 1.

Table l However, ○... Good anti-fogging property △... Water droplets are quite large, but there are few practical problems ×... Not suitable for practical use in sentient state 1st The results in the table show that the anti-fog durability of the anti-fog film according to the invention is significantly improved.

Patent applicant Kokoku Chemical Industry Co., Ltd.

Claims (1)

[Claims] (1) No ultraviolet curing MIH agent on one side of the anti-film.
This is an improved anti-fog lasting paint for an anti-fog film, which is applied to a thickness of 3 to 10μ and cured by ultraviolet irradiation to improve the anti-fog durability of the non-coated surface of the paint. A method for improving the anti-fog durability of an anti-fog film according to claim 1.