WO2001017770A1 - Hygroscopic antifogging film and process for producing the same - Google Patents

Abstract

A film which comprises a film base and formed on a surface thereof a water-absorbing layer comprising a water-absorbing organic polymer, has antifogging properties and the property of allowing droplets to slip off, retains the antifogging properties over long, and can be produced without necessitating any complicated step; a process for producing the film; a method of using the film; a substrate coated with the film; a coating composition for producing the film; and a process for producing the coating composition.

Description

 Description Hygroscopic antifogging film and method for producing the same

 The present invention relates to a film exhibiting anti-fogging properties, a method for producing the film, a method for imparting anti-fogging properties to a substrate using the film, a substrate to which the film is adhered, and a coating composition for producing the film And a method for producing the coating composition. Background art

 It is often experienced that mirrors around water, such as bathrooms and washrooms, become cloudy with steam. The reason why the surface of the member is fogged is that when the surface is placed at a temperature lower than the dew point of the atmosphere, the moisture in the atmosphere condenses and condenses on the surface, and grows in a water droplet shape. If the condensed water droplets are fine enough and their diameter is around 1Z2 of the wavelength of visible light, the water droplets will scatter light and the glass or mirror will be apparently opaque, again losing visibility.

 If the condensation of moisture further progresses and fine condensed water droplets fuse with each other and grow into larger discrete water droplets, their refraction at the water-water interface and the water-air interface will cause their refraction. The surface is dark, blurred, mottled, or cloudy. As a result, in a transparent article such as glass, the perspective image is distorted and the transparency is reduced, and the reflected image is disturbed by a mirror.

 If a large number of discrete drops of water adhere to the surface, such as on a wash mirror, those surfaces can become dull, blurred, mottled, or cloudy, and still lose visibility.

 Needless to say, the above "clouding" has a profound effect on safety and efficiency of various tasks. For example, if the windshield and windowpane of a vehicle or the rearview mirror of a vehicle is shaded or clouded in cold weather or rainy weather, it will be difficult to secure visibility and traffic safety will be impaired. If the cover glass of the instrument panel becomes cloudy, it will be difficult to read overnight.

In order to solve the above problems, various attempts have been made to impart anti-fogging properties and dripping properties to various substrates. Has been done.

 A method in which a surfactant is applied to the surface of a substrate or kneaded into the substrate itself is often used.

 There is also disclosed an example in which a base material is made hydrophilic by using colloidal silica or the like. For example, Japanese Patent Application Laid-Open No. 57-147525 discloses a synthetic resin molded article having excellent drip-free properties in which inorganic aqueous sol particles are deposited on a substrate surface, and a drip-free material containing inorganic colloid particles and a surfactant is applied. Is disclosed.

 PCT / W096 / 29375 discloses a method of forming a photocatalyst-containing layer on the surface of a substrate to impart hydrophilicity to the surface according to the photoexcitation of the photocatalyst. Further, Japanese Patent Application Laid-Open No. Hei 9-222,042 discloses a method of forming a layer containing photocatalyst particles on the surface of a film substrate to impart hydrophilicity to the surface in response to photoexcitation of the photocatalyst. .

 Japanese Patent Application Laid-Open No. 9-1113704 discloses a method of forming a layer containing a hygroscopic organic polymer such as polyvinyl alcohol to impart anti-fogging property.

 However, with respect to the method of imparting hydrophilicity to the surface of these substrates, it is difficult to maintain the effect especially in the area around water in a washroom or the like due to bleeding (dissolving) in the method of kneading a surfactant. In addition, there is a technical problem that if the water film is not uniform due to dirt, the image will be blurred.

 The method of providing a hydrophilic layer on a substrate has a technical problem that the effect of hydrophilicity lasts only for a short period of time, and once the hydrophilicity is lost, the antifogging property is lost.

 In the method of providing a photocatalyst-containing layer on a substrate, the hydrophilicity can be restored by irradiation with ultraviolet rays, but there is a technical problem that it is difficult to restore the hydrophilicity particularly when used indoors.

 In the above method of imparting hydrophilicity, since a water film is formed on the surface, there is a technical problem that a transmitted image or a reflected image is distorted or interference fringes occur. In addition, there is a technical problem that the stained portion loses hydrophilicity and becomes cloudy.

In addition, the method of forming a layer containing a hygroscopic organic polymer has technical problems such as a decrease in strength and cloudiness when the film absorbs water, and it requires a complicated process to adjust the solution to take these measures. There were technical challenges. The present invention has been made in view of the above circumstances, has a simple process, has a long duration of anti-fogging property, and has the durability and durability of a coating film provided on the surface of a base material for imparting anti-fogging property. Film having excellent abrasion resistance, little change in color tone and transparency of the substrate due to the coating film, and imparting antifogging property and drip resistance to the substrate surface, a method for producing the film, and attaching the film It is an object of the present invention to provide a base material with a coating, and a coating composition for producing the film. Disclosure of the invention

 In order to solve the above problems, the present invention provides a film having a water-absorbing layer containing a water-absorbing organic polymer formed on the surface of a film substrate, exhibiting anti-fogging properties and droplets, a method for producing the film, and a film based on the film. A method of imparting anti-fogging property and dripping property to the surface of a base material by attaching it to the surface of a material. A coating for forming a hydrophilic layer containing a water-absorbing organic polymer, which is coated on the surface of a film substrate to impart properties selected from the group consisting of hydrophilicity, dripability, antifogging property, and antifouling property. Provide the composition.

 The first invention is a moisture-absorbing antifogging film exhibiting antifogging properties, wherein a water absorbing layer containing a water absorbing organic polymer is formed on the surface of a film substrate. The moisture-absorbing antifogging film according to the present invention has an effect that the duration of antifogging property is long and the color tone and transparency of the substrate hardly change by the coating film.

Examples of resins for film substrates include polyolefin, polyamide, polyesteramide, polyether, polyimide, polyamideimide, polystyrene, polycarbonate, poly-P-phenylene sulfide, polyetherester, polyvinyl chloride, poly (meth) acrylic. Films composed of acid esters are preferred, and polyester films are more preferred. Among them, polyethylene terephthalate (hereinafter referred to as PET) is particularly suitable for smoothness, dimensional stability, heat resistance, strength, high rigidity, and chemical resistance. It is excellent in terms of moisture resistance, water resistance, transparency and the like, and is very preferable. In particular, when importance is attached to weather resistance, it is preferable to use an acrylic film. Further, in order to impart weather resistance to the film, a film containing an ultraviolet absorber or a radical trapping agent can be used.

 Preferred examples of the water-absorbing organic polymer include polyvinyl alcohol, polyacrylic acid, sodium polyacrylate, and polyalkylene oxide. Among them, polyvinyl alcohol is more preferable because it has excellent film forming properties and physical properties such as tensile strength, tear strength and friction strength are superior to other water-absorbing resins. The transparency is excellent, and the solvent resistance, the acid resistance, and the heat resistance are practically acceptable unless severe.

 Preferred as the polyvinyl alcohol are those having a genification value of 94 to 100%. If the genification value is less than 94%, the water resistance of the water-absorbing film is poor, which is not preferable. A special polyvinyl alcohol having a hydrophobic group introduced into the molecule is preferable because the water resistance is further improved. This special polyvinyl alcohol is sold by Kuraray Co., Ltd. under the name of RS Polymer, for example.

 Suitable polyvinyl alcohols have an average degree of polymerization of 100 to 350, more preferably about 150 to 260. If the degree of polymerization is larger than the preferred range, the viscosity of the coating composition becomes too high, so that the dissolving operation and the coating operation become difficult. Conversely, if the degree of polymerization is too low, the film strength of the water-absorbing layer decreases.

 In the second invention, the moisture-absorbing anti-fog according to the first invention, wherein an easy-adhesion layer is formed between the film substrate surface and the water-absorbing layer, and the opposite surface has no easy-adhesion layer. Film. The moisture-absorbing and anti-fog film according to the present invention, in addition to the effects of the above-described invention, can greatly improve the adhesion between the base film and the coating layer, and can prevent blocking.

 The easy-adhesion layer (primer) is formed to enhance the adhesion layer between the base film and the coating layer. Furthermore, it is preferable that an easy-adhesion layer (primer) is not applied on the back side of the surface to be coated to prevent blocking. Blocking refers to the sticking of the films in contact with each other, and is likely to occur if the film is left in a rolled state under high temperature or high humidity conditions.

A third invention provides a method of manufacturing a film substrate according to the first aspect, wherein the water-absorbing layer is formed on the opposite side of the film substrate. The moisture-absorbing anti-fog film according to the first or second invention, wherein an adhesive layer and a release film are formed on the surface. In addition to the effect of the invention, the moisture-absorbing antifogging film according to the present invention can easily form an antifogging composite by sticking the film on various substrates. Preferably, a release film may be provided on the surface of the adhesive layer. Further, instead of providing the adhesive layer on the entire surface to be attached, a partial bonding means can be provided.

 Base materials to which the film according to the present invention can be applied include mirrors for wash basins, glass for vehicles, window glasses for buildings, mirrors for vehicles, road mirrors, instrument panel covers, eyeglass lenses, helmet shields, goggles, A heat-insulated showcase or the like is mentioned as a preferable example, but is not limited to this.

 A fourth invention is the moisture-absorbing anti-fog film according to any one of the first to third inventions, further comprising a protective film on the surface of the water-absorbing layer. The moisture-absorbing and anti-fog film according to the present invention, in addition to the effects of the above-mentioned invention, the protective film is usually peeled off after the application to the substrate, and the film absorbs moisture during storage and transport, contamination, blocking, abrasion, etc. It is possible to prevent damage and functional deterioration due to a squeegee at the time of attaching.

 A fifth invention is the moisture-absorbing anti-fog film according to any one of the first to fourth inventions, wherein the water-absorbing layer further contains a binder containing an inorganic binder as a component. The moisture-absorbing anti-fog film according to the present invention can provide sufficient film strength and water resistance in a relatively short heating time in addition to the effects of the above-described invention.

 Preferable inorganic binders include inorganic binders containing a zirconium atom. Zirconium is said to have better water, acid and alkaline resistance than other gays, titanium and aluminum.

Preferred as the inorganic binder containing a zirconium atom are zirconium oxide, hydroxide, oxyhydroxide, oxynitrate, oxycarbonate, halide, oxyhalide, nitrate, sulfate, and carbonate. An ammonium salt can be mentioned, and among them, zirconyl nitrate (zirconium oxynitrate) is particularly preferable. This can increase the curing speed simply by mixing it with an aqueous polyvinyl alcohol solution, The alkali resistance is improved, and the stability of the liquid is maintained for about two weeks. Zirconium oxychloride has the same effect, but it releases hydrochloric acid and may cause corrosion if stainless steel is used in the container and the coating equipment. In addition to these, there are other raw materials such as alkoxides, but the hydrolysis and polycondensation reactions are relatively fast and difficult to handle. The addition amount of zirconium oxychloride is preferably 2 to 5 parts based on 100 parts of the solid content of polyvinyl alcohol. If it is larger than the preferred range, it causes coloring, and if it is smaller, sufficient water resistance cannot be obtained.

 A sixth invention is the moisture-absorbing anti-fog film according to any one of the first to fifth inventions, wherein a catalyst is used for promoting crosslinking of the water-absorbing layer by the binder. The moisture-absorbing and anti-fog film according to the present invention can improve water resistance and film strength by promoting crosslinking in addition to the effects of the above-described invention.

Examples of the catalyst include metal salts of carboxylic acids such as alkyl titanates, tin octylate, dibutyltin dilaurate, and dioctyltin dimaleate; dibutylamine-2-hexoate; dimethylamine acetate; ethanolamine acetate; Amines, amines such as tetraethylpentamine, monoethanolamine, N, N-dimethylbenzylamine, n-hexylamine, tributylamine, ethylenediamine, hexanediamine, diethylenetriamine, triethylenetetramine, etc., N -Amine-based silane coupling materials such as 3-aminoethyl-a-aminopropylmethyldimethoxysilane, P-toluenesulfonic acid, fumaric acid, acetic acid, hydrochloric acid, nitric acid, sulfuric acid, propionic acid, maleic acid, adipic acid , Fumaric acid, valeric acid, lactic acid, butyric acid, Acids such as acid, malic acid, picric acid, formic acid, and carbonic acid, aluminum compounds such as aluminum chelate, aluminum acetyl acetate, aluminum perchlorate, aluminum chloride, aluminum isobutoxide, and aluminum isopropoxide Titanium compounds such as tetraisopropyl titanate and tetrabutyl titanate; lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium methylate, sodium acetate, sodium formate, potassium acetate, potassium formate, potassium propionate, tetra Basic compounds such as methylammonium chloride, tetramethylammonium hydroxide, and ammonia; tin acetyl acetate, dibutyl tin octylate Metal compounds such as cobalt octylate, cobalt acetyl acetate, iron acetyl acetate, and peroxides such as hydrogen peroxide.

 These catalysts can be used alone or in combination.

 These catalysts can be mixed with the coating composition from the beginning, or can be mixed with the coating composition immediately before coating.

 A seventh invention is the moisture-absorbing anti-fog film according to the sixth invention, wherein the acid released from the zirconium salt has the role of the catalyst. For example, hydrochloric acid is released from zirconium oxychloride. The moisture-absorbing anti-fogging film according to the present invention can simplify the process in addition to the effects of the above-described invention, without the necessity of separately adding a catalyst. An eighth aspect of the present invention is the hygroscopic property according to any one of the first to seventh aspects, wherein the water-absorbing layer further contains a surfactant, and exhibits anti-fog properties due to drip properties even when the amount of absorbed water is saturated. It is an anti-fog film. Since the surface of polyvinyl alcohol itself is not necessarily hydrophilic, fogging occurs when the amount of absorbed water is saturated.However, the use of a surfactant can impart drip properties, preventing even if the amount of absorbed water is saturated. Cloudiness can be maintained. Note that a water-absorbing layer having both hydrophilic properties by the action of a surfactant is referred to as a hydrophilic water-absorbing layer.

 There are a great number of types of the above-mentioned surfactants, but those which can be added to impart dripping properties are limited in practice. As a result of the experiment, it was possible to give droplets with polyoxyethylene alkyl ether or perfluoroalkenylpolyoxetylene ether (both nonionic). However, the types need not be limited to these. Also, it is not always necessary to use a nonionic system. The amount of the surfactant to be added depends on the type of the surfactant, but is preferably 0.02 to 0.5 part by weight based on 100 parts by weight of the solid content of polyvinyl alcohol and the binder. If it is smaller than this range, the hydrophilicity of the surface is not sufficient, and if it is larger than this range, poor appearance (haze), decrease in film strength, and stickiness are caused.

A ninth invention is the moisture-absorbing anti-fog film according to any one of the first to eighth inventions, wherein the water-absorbing layer further contains an antibacterial metal or a compound thereof. Antibacterial gold The genus includes silver, copper, and the like. The antibacterial action of the antibacterial metal can suppress the generation and reproduction of bacteria to some extent. Alternatively, organic antibacterial agents such as imidazoles can be used.

 A tenth invention is the moisture-absorbing anti-fog film according to any one of the first to ninth inventions, wherein the water-absorbing layer further contains an antifungal agent and / or an antibacterial agent. Antifungal action can suppress the occurrence and reproduction of mold to some extent. Since the main component of the solvent of the coating agent in the present invention is water, it is preferable that the antifungal agent is also water-soluble. There are few water-soluble industrial antifungal agents. For example, the coat side of Takeda Pharmaceutical Co., Ltd. is water-soluble and can be suitably used.

 An eleventh invention is directed to a binder containing the polyvinyl alcohol according to the first invention as a main component in a solvent containing water as a main component, a binder according to the fifth invention, and a solvent according to the sixth or seventh invention. The catalyst according to the eighth aspect, the surfactant according to the eighth invention, the antibacterial metal or the compound thereof according to the ninth invention, the antifungal agent according to the tenth invention, the antibacterial agent are appropriately selected, or all are selected. Coating composition being added. Thus, for example, application to a substrate such as glass or a mirror can be considered.

 The water-absorbing layer in the above invention may contain cerium, a compound containing a cerium atom, a benzotriazole-based, benzophenone-based, salicylate-based, cyanoacrylate-based, agizanilide-based ultraviolet absorber, or the like. When attached, UV rays that are harmful to the human body can be cut.

 The water-absorbing layer in the above invention may contain fine particles in order to impart anti-blocking properties, lubricity, anti-blocking properties and the like.

 Preferable examples of the fine particles include cerium oxide, tin oxide, colloidal silica, colloidal alumina, colloidal zirconia, colloidal titania, emulsions such as acryl emulsion, acrylate-coated polyester fine particles, and the like.

The thickness of the film used in the above invention is not particularly limited. However, if the film is too thin, there are problems of handling properties and incurling (the curling of the film with the coated surface inward). Due to problems, those having a length of 50 to 100 m are preferable. The preferred thickness of the water-absorbing layer of the film in the above invention is 5 m to 15 m. If the thickness of the hydrophilic layer is more than the preferable upper limit, drying during film production may become difficult due to bumping of the coating composition or the like, and the water-absorbing layer may have poor water resistance and durability. If the thickness is below the preferred lower limit, the water absorption of the water-absorbing layer will be low and the anti-fogging time will be short.

 The viscosity of the coating composition for a film in the present invention is from 200 to 2000 cps. If the viscosity is higher than the preferable range, defoaming and filtration take a very long time, which is not preferable. If it is lower than the preferable range, it becomes impossible to apply by a die coater.

 The viscosity of the coating composition is highly dependent on the concentration of poval. In addition, it also depends on the generative value, the degree of polymerization and the temperature of the liquid. For example, in the case of the RS polymer having a degree of polymerization of 1700 used in the examples, since the concentration corresponding to this viscosity is 6-1 at 3 (T, the solid concentration of polyvinyl alcohol in the coating composition is 6 to 12%. Alcohol may be added as a defoaming agent to the coating composition, and propyl alcohol, 2-propyl alcohol and ethyl alcohol having a boiling point lower than that of water are preferable. In the case of 2-propanol, the addition amount is preferably 2 to 5% If the amount is less than the preferred range, the defoaming effect is not sufficient, and if the amount is greater than the preferred range, the appearance of the film may be adversely affected. It is to be noted that methyl alcohol is not preferred because it has a small defoaming effect The film of the present invention can be used by attaching it to a substrate.

 The base material includes a wash mirror, a vehicle glass, a building window glass, a vehicle mirror, a road mirror, an instrument panel cover, an eyeglass lens, a helmet shield, goggles, and a heat-insulating showcase.

 The film in the present invention may be used as a general-purpose product in the form of a roll, a sheet, a ribbon, or the like, or may be used as a precut to be attached to a specific substrate.

Examples of the specific base material include a wash mirror, a vehicle glass, a building window glass, a vehicle mirror, a road mirror, an instrument panel cover, an eyeglass lens, a helmet shield, a gore, and a heat insulating showcase. A twelfth invention provides a step of preparing a film serving as a substrate, a step of applying the coating composition according to the eleventh invention to the film, and thereafter, 80 T: not less than 170, more preferably And a method for producing a moisture-absorbing and anti-fog film comprising: drying at 120 to 150. According to the present invention, a moisture-absorbing and anti-fog film having favorable durability, water resistance, and appearance can be produced.

 Examples of the resin for the film substrate include polyolefin, polyamide, polyesteramide, polyether, polyimide, polyamideimide, polystyrene, polycarbonate, poly-P-phenylene sulfide, polyetherester, polyvinylchloride, and poly (meth) acrylate. A film made of an acrylate ester or the like is preferable, and a polyester film is more preferable. Among them, polyethylene terephthalate (hereinafter referred to as PET) is particularly suitable for smoothness, dimensional stability, heat resistance, strength, high rigidity, Excellent in terms of chemical properties, moisture resistance, water resistance, transparency, etc., and is very preferable. In particular, when importance is attached to weather resistance, it is preferable to use an acrylic film.

 Further, in order to impart weather resistance to the film, a film containing an ultraviolet absorber or a radical trapping agent can be used.

Reverse coating, die coating, knife coating, doctor blade coating, various bar coating, dip coating, gravure roll coating, calender coating, skies There are coating, kiss coating, fountain coating, spray coating, flow coating, etc., which can be appropriately selected according to the properties of the coating composition, production lot, and the like. In addition, the die coating is less likely to foam the coating composition during application (there is less generation of bubbles) and can improve the appearance after drying. If vacuum degassing is performed to remove air bubbles inside, the appearance will be further improved without air bubbles after drying. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a diagram showing a film manufacturing apparatus. BEST MODE FOR CARRYING OUT THE INVENTION

 Embodiments according to the present invention will be described below based on examples. The present invention is not limited by these examples.

 (Example 1)

 RS polymer having a polymerization degree of 1700 (genification value: 97-99%) was added to distilled water, heated at 90 and dissolved with stirring to prepare a 9% aqueous solution. Zirconium oxynitrate dihydrate was dissolved in distilled water to prepare a 6% aqueous solution. 0.15 kg of the aqueous solution was added to 4 kg of the polyvinyl alcohol aqueous solution. Further, 0.4 kg of a 25% aqueous solution of 2-propanol was added, and the mixture was stirred for 10 minutes. This was allowed to stand for 24 hours to prepare Coating Composition 1.

 Each of the coating compositions 1 to 4 was applied to an easily adhesive PET film having a thickness of 100 m using an apriquet overnight, and then dried at 140 for 4 minutes to obtain an example film 1. The thickness of the hydrophilic layer after drying was about 10 m.

 The same film without the coating treatment is referred to as Comparative Example Film 1. There was no significant difference in the visual appearance in transparency between the example of Film 1 and the comparative example. The haze (degree of haze) in Comparative Example 1 was 1.25, whereas that in Example 1 was rather small at 0.85. This is probably because the unevenness of the easy-adhesion layer is filled with the moisture-absorbing layer and becomes smooth.

 After the film 1 was cooled in a minus 5 ^ freezer for 2 minutes and then brought to room temperature, the coated surface of the example did not become cloudy, whereas the comparative example immediately became cloudy. The pencil hardness of the hydrophilic layer of the example was F and did not dissolve in water or an alcohol such as ethyl alcohol. Even when the coated surface was brought into contact with a 1% aqueous sodium hydroxide solution and a 1% aqueous hydrochloric acid solution for 1 hour, the anti-dew film was not dissolved or peeled off. The film 1 of the example was affixed to a wash mirror and the maintenance of the anti-fogging property was examined for 6 months. As a result, the anti-fogging property was completely maintained after 6 months.

 (Example 2)

Polyvinyl alcohol with a polymerization degree of 1700, with a saponification value of 98-99% (complete test), 94.5 Coating composition 24 was prepared in the same manner as in Example 1 for three types: 95.5% (intermediate degradation) and 87 89% (partial degradation). The coating composition 24 was applied to a 100-m-thick easily-adhesive-treated PET film using an applicator, and dried at 140 for 4 minutes to obtain Example Film 1.

 Example 14 A comparison was made between the results obtained by applying water to the film 14 and sliding the film 14 back and forth with a plastic squeegee. The smaller the haze value, the better the sliding resistance. The haze is preferably 2 or less even after sliding. RS polymers are even more preferred because of their reduced haze. Although the haze of the partially-modified product is smaller than that of the intermediate-provisioned product, it is considered that the surface of the partially-modified product is uneven due to visual observation.

【table 1】

 Table: Degree of trial and sliding resistance when wet

 Haze

 Flum! Part number! After the dissolution! After being called! Remarks

 l! RSl l ?! Kan .iL85! Li0i ——.

 — 2J? 1-—-0.91-1.98 · 98

 3ΪΡΥΑ617! Between Φ. 0.83:. „2..49ί ί

 4IPVA217! Part 0.84! 2.12 "Sticky

* RS is the product number of the water-resistant polymer. The antifogging test was performed on the Example Film 14 as follows.

 The film coated with the hygroscopic film was allowed to dry in a dryer at 50 for 30 minutes. A constant temperature water bath was prepared and kept at a water temperature of 35 for 30 minutes so that the humidity inside became 100%. The distance from the lid to the liquid surface was 5 cm. The film was taken out of the dryer, a part of the lid was opened, the film was placed, and a glass plate was placed. The time until the film became 1/3 cloudy was defined as the anti-fog time. The room temperature during the test was maintained at 27. There was no significant difference between the mid-term trial and the complete trial with an anti-fogging time of about 8 minutes and 30 seconds. RS polymer had a slightly shorter antifogging time of 6 minutes and 30 seconds. The partially saponified product had a long anti-fogging time, but was unsuitable for practical use because haze remained after the test. There were few intermediate products, but haze remained.

In the test where the film surface temperature was kept at 5 and the water tank was kept at 30 The anti-fogging time was about 1 minute and 30 seconds for all of the commercial products, fully tested products, and intermediately tested products. The partially purified product did not become cloudy after more than 5 minutes, but the surface had swollen.

 (Example 3)

 RS polymer having a polymerization degree of 1700 and a saponification value of 97 to 99% was dissolved in distilled water to prepare a 9% aqueous solution. 0.025 kg, 0.05 kg, 0.75 kg, 0.1 kg, 0.125 kg, 0.15 kg, 0.1 kg, 0.25 kg of a 6% aqueous zirconium nitrate solution were added to 4 kg of this aqueous solution. Further, after adding 0.4 kg of 2-propanol, the mixture was stirred for 10 minutes and left for 24 hours to obtain coating agents 5 to 12. Zirconium nitrate is 0.5, 1, 1.5, 2, 2.5, 3, 4, and 5 parts by weight with respect to 100 parts by weight of polyvinyl alcohol in coating agents 5 to 12. A 100-micron PET film that had been easily bonded was coated all over Apriquet so that the dry film thickness was 10 microns. The film was dried with a dryer at 14 (T, 4 minutes) to obtain Examples 5 to 12.

 As in the previous case, the haze value of each of Example films 5 to 12 after rubbing 50 times with a squeegee was measured to examine the water resistance. Also, the color difference from before coating was measured. If the amount of zirconium oxynitrate is large, it turns yellow, so it was found that the following is preferred. If the amount is too small, the water resistance will be lost. The pH was about 3 at 2.5%.

 [Table 2] Table: Crosslinking agent concentration, water resistance and coloring

(実施例 4)

(Example 4)

 The following various surfactants were added to the coating composition 1 prepared in Example 1 to prepare coating compositions 13 to 23. The addition amount was 0.369 g for 4 kg of the additive. It is 0.01 parts by weight based on 100 parts by weight of solid content of polyvinyl alcohol and zirconium oxynitrate. Coating compositions 13 to 23 were coated on a 100-micron PET film that had been subjected to easy adhesion treatment so that the dry film thickness became 10 microns throughout the application. The film was dried in a drier at 140 for 4 minutes to obtain Examples 13 to 23. The contact angles and haze of these films were measured. From Table 3, it is preferable to add Gran Echo Ml 2 because the contact angle is reduced. Some nonions (non-ion) have a high contact angle, so they cannot be said to be good.

(13) Gran Echo M-12 polyoxyethylene alkyl ether, manufactured by Sanyo Chemical Industry Co., Ltd.

 (14) FT-251 perfluoroalkenyl polyoxyethylene ether, manufactured by Neos Co., Ltd.

 (15) Beaulite A5000 Polyoxyethylene lauroyl sulfooctanoate, sodium amidonidium, manufactured by Sanyo Chemical Industries, Ltd.

 (16) Repon 2000L Amidopropyl laurate bayone solution, manufactured by Sanyo Chemical Industries, Ltd.

 (17) Levon 2000HG Aminopropyl coconut oil fatty acid in palm oil, manufactured by Sanyo Chemical Industries, Ltd.

 (18) IONET T80C Polyoxyethylene sorbitan monooleate, manufactured by Sanyo Chemical Industry Co., Ltd.

 (19) IONET T60C Polyoxyethylene sorbitan monostearate, manufactured by Sanyo Chemical Industries, Ltd.

 (20) TG-C Lipophilic glyceryl monostearate, manufactured by Sanyo Chemical Industries, Ltd.

PEG6000S polyethylene glycol, manufactured by Sanyo Chemical Industry Co., Ltd.

(21) Tween20 polyoxyethylene sorbitan monolaurate (22) Tween40 Po

 (23) Tween80 Po

 [Table 3] Table: Types of surfactants, contact angles and external parents

(Example 5)

15 When the surfactant Glan Eco-1 M-12 was added to the coating composition 1 prepared in Example 1, the contact angle and appearance (haze) were measured by changing the amount of addition. Coating compositions 24-29 were obtained by adding 0.0369 g, 0.738 g, 0.185 g, 0.369 g, 0.738 g, and 1.85 g to 4 kg of the coating composition. For 100 parts by weight of the solid content of polyvinyl alcohol and zirconium oxynitrate, the value of Gran Echo M-120 is 0.01, 0.02, 0.05, 0.1, 0.2, 0.5 part by weight. The coating composition 24-29 was coated on a 100-micron PET film that had been subjected to an easy-adhesion treatment using an applicator so that the dry film thickness was 10 microns, and then dried at 140T in a dryer for 4 minutes. Films 24-29 were obtained. According to Table 4, if the solid content ratio of the surfactant is 0.01% or less, the hydrophilicity of the surface is not sufficient, and if it is 0.5% or more, poor appearance (haze) may be caused. In addition, a decrease in film strength and stickiness were observed. Therefore, the amount of the surfactant added is preferably 0.02% or more and less than 0.5%. [Table 4] Table: Amount of surfactant, contact angle and appearance

(Example 6)

When coating the coating composition 1 prepared in Example 1 on an easily adhered PET film having a thickness of 100 μm with an applicator, the thickness was changed by adjusting the gap of the applicator over time. . The film was dried in a drier at 140: 4 for 4 minutes to obtain Examples 30 to 36. The measured film thickness was 2.2 microns for Example Film 30, 4.3 microns for Example Film 31, 5.1 microns for Example Film 32, 6.0 microns for Example Film 33, and Example Film. 34 was 7.6 microns, Example Film 35 was 8.6 microns, and Example Film 36 was 11.4 microns. Example films 30 to 36 were compared for anti-fog time. Since the amount by which the water-absorbing layer can absorb moisture depends on the film thickness, it was confirmed that the antifogging time depends on the film thickness. At 5 microns, the antifogging time is less than 5 minutes, so a film thickness of 6 microns or more is preferred. In a coating device for production, if the drying time is as short as about 3 minutes, if the film thickness is thicker than 19 microns, the coating composition will be difficult to dry and bumping will easily occur, which may cause poor appearance. I understood. At 15 microns, it could be applied without any problems. Therefore, the film thickness is preferably 6 microns or more and 15 microns or less. [Table 5] Table: Relationship between moisture absorption layer thickness and antifogging time

(Example 7)

 When coating the coating composition 1 prepared in Example 1 on a 100-micron PET film that has been easily adhered, the heating time was changed to 1 minute, 2 minutes, 3 minutes, and 4 minutes. Example films 37-39 were obtained. The film thickness was 10 microns and the heating temperature was 140. Example films 37 to 39 were subjected to a sliding test.

 Polyvinyl alcohol generally has a higher heating temperature, and the longer the heating time, the higher the crystallinity and the higher the water resistance. However, if it is too high, it will be decomposed.

Considering the heat resistant temperature of PET, the upper limit of the heating temperature is about 145. From the table, it is preferable for O to be 4 minutes or more, but in the actual coating machine, it could be raised to 145, and the conditions such as air volume were different, so it was enough to cure in about 3 minutes.

 [Table 6]

Table: ra during heating and water resistance

(Example 8)

The following types of alcohol were added to the coating composition 1 of Example 1 at concentrations of 2, 5, and 10%. 00/05994

 18 to obtain coating compositions 30 to 41. Coating compositions 30 to 41 were examined for disappearance of bubbles on the liquid surface. Coating compositions 30 to were coated on a 100-micron PET film which had been subjected to an easy-adhesion treatment so that the dry film thickness became 10 microns throughout the application, to obtain Example films 40 to 51. Example films The appearance of the films 40 to 51 was observed.

 2-Propyl alcohol (compositions 30 to 32, films 40 to 42): Even a small amount of 2% can be suitably used because the defoaming effect can be obtained. However, if the amount of addition is more than ¾, “undulation” (wrinkles) occurs, so that the addition amount is preferably less than ^. Boiling point 82.4 :.

Tripropyl alcohol (compositions 33-35, films 43-45): Higher defoaming effect than ethanol. However, at 10%, less than 10% is preferred because the film has uneven appearance. Boiling point 97. 15T :.

Ethyl alcohol (compositions 36-38, films 46-48): Defoaming effect is not very high, but toxicity is lower than other alcohols. However, the price is high. Boiling point 78.3 t :. Methyl alcohol (compositions 39 to 41, films 49 to 51): Undesirable defoaming effect and undesired cohesive action. Boiling point at 64.7.

 [Table 7] Table: Addition of alcohol and defoaming effect and appearance of film

XX: Full surface X: 1/2 or more △: △ / 8 to 1/2 〇 1/8 or less Turbidity: visually judged after 5 days (Example 9)

 A fungicide was added to the coating composition 1 of Example 1 to evaluate the appearance of the film. Those having a good appearance were evaluated for their antifungal properties.

 The coating compositions 42 to 44 were prepared by adding 0.2 parts by weight of Takeside Pharmaceutical Co., Ltd., and Zeneki Densir S 100 and Vanquish 100, respectively, to 100 parts by weight of the coating composition. The coating compositions 42 to 44 were coated on a 100-micron PET film which had been subjected to an easy-adhesion treatment so that the dry film thickness became 10 μm at the time of application, to obtain Example films 52 to 54.

 Both Densil S 100 and Vanquish 100 are water-insoluble, and when mixed with a PVA solution, the solution becomes cloudy, and the haze increases due to the particles remaining even when applied to the film. A defect has occurred. Takeda Pharmaceutical's coatside has excellent compatibility with the PVA solution, and did not cause appearance defects. However, there was no effect on some rickets.

 (Example 10)

 Next, an example of the present method for producing a film according to the present invention will be described. Figure 1 shows the film production equipment.

 Hereinafter, description will be made with reference to the drawings.

 36 kg of RS polymer having a polymerization degree of 1700 (saponification value 97 to 99¾) was added to 364 kg of distilled water, heated at 60 for 1 hour with stirring in a closed vessel, and allowed to cool naturally. Stirring was further continued for 18 hours to swell. The temperature was raised again while stirring, and the temperature was kept at 95 or more for 1 hour, followed by natural cooling to prepare a 9% aqueous solution. 0.9 kg of zirconium nitrate dihydrate was dissolved in 14. l kg of distilled water to prepare 15 kg of a 6% aqueous solution. The aqueous solution was added to the polyvinyl alcohol aqueous solution. Further, 40 kg of a 25% aqueous solution of 2-propanol, 0.0369 kg of a surfactant Glan-Echo M-12, and 0.8 kg of a fungicide side coat were added, followed by stirring for 10 minutes. This was allowed to stand for 24 hours to prepare a coating composition for production.

 First, an easily-adhesive treated polyethylene terephthalate (PET) film having a thickness of 50 was prepared and mounted on the film roll 1 before applying the paint.

Next, the coating composition (paint) was placed in the paint tank 4 with a defoaming device. The reason why the defoaming device is provided is to remove air bubbles in the coating composition before applying the coating composition to further improve the final appearance.

 Next, the film mounted on the film roll 1 before applying the paint was unwound at a constant speed, the die coater head 5 was pressed against the film, and the paint was attached to the film surface. At this time, the film amount of the coating composition was adjusted to 10 m by adjusting the amount of the paint to be sent out from the paint tank 4 with the defoaming device to 1.3 mL Zmin and the sending speed of the film to 7.3 lm / min. It was adjusted to become. The coating method is not limited to the die coating method of the present embodiment, but the die coating method is less likely to cause bubbles in the coating composition at the time of coating, so that the generation of bubbles is small. This is preferable since the appearance after drying can be improved.

 Next, the first drying oven is set to 120, the second drying oven is set to 140, the third drying oven is set to 1450, and the fourth drying oven is set to 13.5 to cure the paint. The film is passed through drying ovens 6 to 9 at a film feed rate of 7.1 lmXmin to promote drying and curing of the paint, and finally, the film coming out of the drying oven 6 for curing the paint. The film was wound on a film roll 2 after applying the paint. Industrial applicability

 According to the present invention, the process is simple, does not require expensive and large-scale equipment, does not require a high-temperature heat treatment process, has a long duration of antifogging property, and has a substrate surface for imparting antifogging property. Durability of the coating film provided on the surface ゃ Excellent abrasion resistance, little change in color and transparency of the substrate due to the coating film, no need for light to express hydrophilicity, anti-fog on the surface of the substrate Film for imparting water and dropping properties, method for producing the film, method for using the film, substrate to which the film is adhered, coating composition for producing the film, and coating composition A method for manufacturing a product can be obtained.

Claims

The scope of the claims  1. A moisture-absorbing antifogging film exhibiting antifogging properties, wherein a water-absorbing layer containing a water-absorbing organic polymer is formed on the surface of a film substrate.  2. The moisture-absorbing anti-fog film according to claim 1, wherein an easy-adhesion layer is formed between the surface of the film substrate and the water-absorbing layer, and the opposite surface has no easy-adhesion layer. 3. The moisture-absorbing anti-fogging film according to claim 1, wherein an adhesive layer and a release film are formed on the surface of the film substrate opposite to the surface on which the water-absorbing layer is formed.  4. The moisture-absorbing anti-fog film according to any one of claims 1 to 3, further comprising a protective film on the surface of the water-absorbing layer.  5. The moisture-absorbing anti-fogging film according to any one of claims 1 to 4, wherein the water-absorbing organic polymer contains polyvinyl alcohol.  6. The moisture-absorbing anti-fog film according to claim 5, wherein the average degree of polymerization of the polyvinyl alcohol is 1000 to 350, and the degree of saponification is 94 to 100%. 7. The moisture-absorbing anti-fog film according to any one of claims 1 to 6, wherein the water-absorbing layer further contains a binder containing an inorganic binder as a component. 8. The moisture-absorbing anti-fog film according to claim 7, wherein the inorganic binder contains an inorganic binder containing a zirconium atom.  9. The inorganic binder containing a zirconium atom is zirconium oxide, hydroxide, oxyhydroxide, oxynitrate, oxycarbonate, halide, oxyhalide, nitrate, sulfate, ammonium carbonate. 9. The moisture-absorbing anti-fog film according to claim 8, which is selected from the group consisting of:  10. The moisture-absorbing anti-fogging film according to any one of claims 7 to 9, wherein the binder is contained in an amount of 2 to 5 parts by weight based on 100 parts by weight of the water-absorbing organic polymer.  11. The moisture-absorbing anti-fog film according to any one of claims 7 to 10, wherein a catalyst is used to promote crosslinking of the water-absorbing layer by a binder. 12. The moisture-absorbing antifogging film according to claim 10, wherein the role of the catalyst is given to the acid liberated from the zirconium salt. 13. The moisture-absorbing protection according to any one of claims 1 to 12, wherein the water-absorbing layer further contains a surfactant, and exhibits anti-fog properties due to dripping even when the amount of absorbed water is saturated. Cloudy film.  14. The moisture-absorbing anti-fog film according to any one of claims 1 to 13, wherein the surfactant is a nonionic surfactant.  15. The moisture-absorbing anti-fog film according to any one of claims 1 to 14, wherein the water-absorbing layer further contains an antibacterial metal or a compound thereof.  16. The moisture-absorbing anti-fog film according to any one of claims 1 to 15, wherein the water-absorbing layer further contains an antifungal agent or Z and an antibacterial agent.  17. The moisture-absorbing anti-fog film according to any one of claims 1 to 16, wherein the water-absorbing layer has a thickness of 5 Xm to 15 m.  18. In a solvent containing water as a component, the polyvinyl alcohol according to claim 5 or 6 is contained as a component, The binder according to any one of claims 7 to 10, The catalyst according to claim 11 or 12, Surfactant according to claims 13 or 14, An antibacterial metal or a compound thereof according to claim 15, Antifungal agent, antibacterial agent according to claim 16 Is a coating composition selected as appropriate.  1 9. A step of preparing a film to be a base; A step of applying the coating composition according to claim 18 to the film, and thereafter, a step of drying at 80 or more and 170 or less, A method for producing a moisture-absorbing anti-fog film having: