JP2010184821A - Method for producing anti-fogging laminate glass - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of improving production efficiency of anti-fogging laminate glass. <P>SOLUTION: The method of producing the anti-fogging laminate glass has: a step 1 of forming a coating film comprising a urethane resin having oxyethylene chain and having 10-40 wt.% water absorption coefficient on the surface of a glass base material; a step 2 of laminating a glass base material on which the coating film is formed, an interlayer for the laminate glass and other glass base materials in this order to form the laminate glass by heating; and a step 3 of supporting a surfactant on the coating film. In the step 3, the surfactant is supported in the coating film by applying a coating liquid containing the surfactant on the surface to be coated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for efficiently producing a laminated glass having antifogging properties.

  In view of safety, laminated glass is preferably used for sheet glass articles such as a glass wall surface such as a vehicle window glass such as a vehicle windshield, a building window glass, and a partition. The plate-like glass article is preferably provided with an anti-fogging coating as having anti-fogging properties because the glass surface becomes clouded by water droplets and hinders visibility.

Patent Documents 1 and 2 disclose a sheet-like glass article having an antifogging film formed thereon, in which a water-absorbing film is formed on a glass substrate, and then a surfactant is supported in the film. Laminated glass is disclosed as an example of a glass substrate.
JP 2007-284532 A JP 2008-074694 A

  In the laminated glass formed by the glass substrate and the interlayer film for laminated glass, since the interlayer film has thermoplasticity, it is necessary to avoid that the laminated glass is heated beyond the temperature at which the interlayer film is plasticized. There is. Therefore, when forming a film on a laminated glass, it is preferable that the heating temperature for forming a film does not exceed 100 degreeC. However, the heating temperature impairs the efficiency of film formation.

  An object of the present invention is to provide a method for improving the production efficiency of an antifogging laminated glass.

The production method of the anti-fogging laminated glass of the present invention is a glass substrate having a water absorption rate of 10 to 40% by weight of oxyethylene chains.
Step 1 of forming a film made of a retane resin,
Step 2 in which the glass substrate on which the coating film is formed, an interlayer film for laminated glass, and another glass substrate are stacked in this order and laminated into glass by heating, and a step 3 in which a surfactant is supported in the coating film ,
In step 3, the surfactant is supported in the coating by applying a coating solution containing the surfactant to the coating surface.

  In the present invention, when an efficient method for producing an antifogging laminated glass having a film formed thereon has been intensively studied, the film formed on the surface of the glass substrate is subjected to the above-mentioned step 2 and the hydrophilicity of the film surface. However, it was found that the water absorption of the film was not significantly reduced. In the laminated glass on which the coating film formed through the step 2 is formed, the coating film exhibits at least water absorption, and by performing the step 3, a laminated glass having excellent antifogging properties can be obtained. can do.

  In step 3, the coating only needs to have water absorption. Utilizing this knowledge of the present invention, in Step 1, if a film made of a urethane resin having an oxyethylene chain having a water absorption of 10 to 40% by weight is formed on the surface of the glass substrate, the heat treatment in Step 2 is performed. Even if it passes through, it becomes possible to carry | support a surfactant in a film only by apply | coating the coating liquid containing a surfactant to the film surface at the process 3. FIG.

  The present invention has an effect on the productivity efficiency of the antifogging laminated glass.

The production method of the anti-fogging laminated glass of the present invention is a glass substrate having a water absorption rate of 10 to 40% by weight of oxyethylene chains.
Step 1 of forming a film made of a retane resin,
Step 2 in which the glass substrate on which the coating film is formed, an interlayer film for laminated glass, and another glass substrate are stacked in this order and laminated into glass by heating, and a step 3 in which a surfactant is supported in the coating film ,
In step 3, the surfactant is supported in the coating by applying a coating solution containing the surfactant to the coating surface.

  In step 1, a film made of a urethane resin having an oxyethylene chain having a water absorption rate of 10 to 40% by weight is formed on the surface of the glass substrate. As the glass substrate, soda lime silicate glass is typically used. The glass is a glass that is usually used for automobiles, buildings, industrial glasses and the like, and is produced by a float method, a duplex method, a roll-out method, or the like.

  As glass types, it can be used for various colored glasses such as clear, green and bronze, various functional glasses such as UV, IR cut glass and electromagnetic shielding glass, netted glass, low expansion glass, zero expansion glass and fireproof glass. Various glass products such as glass, tempered glass and the like, mirrors produced by the silvering method or vacuum film-forming method, and flat plates and bent plates can be used. The plate thickness is not particularly limited, but is preferably 1.0 mm or more and 10 mm or less, and is preferably 1.0 mm or more and 5.0 mm or less for vehicles.

  “Consisting of a urethane resin having an oxyethylene chain with a water absorption of 10 to 40% by weight, obtained by mixing a compound having an isocyanate group (NCO group) on the outermost surface of the glass substrate and a polyol having an active hydrogen group. A coating liquid (hereinafter referred to as a film-forming coating liquid) for forming a “coating” is applied to the substrate, and preferably the film is cured by heating at 80 ° C. to 140 ° C. for 10 minutes to 60 minutes. A film made of a urethane resin having a water absorption of 10 to 40% by weight is obtained.

  The coating method of the film-forming coating solution is a well-known method such as roll coating, dip coating, brush coating, spray coating, bar coating, knife coating, die coating, spin coating, curtain coating, and hand coating. Can be done by the method. After coating, the solvent in the coating solution is preferably dried by heating at 80 ° C. to 140 ° C. for 10 minutes to 60 minutes to form a film.

  In addition to the NCO group-containing compound and the polyol antifogging urethane component, the coating liquid for forming a film includes a surfactant for imparting hydrophilicity to the film, an organotin compound as a curing catalyst, and a filler, if necessary. Ingredients, diluent solvents can be added. As the surfactant, a surfactant having a hydroxyl group, amino group, or mercapto group that can react with the NCO group may be used. And preferably, a coating liquid is prepared by mixing the compound which has NCO group, and the mixture of a polyol.

  For the compound having an NCO group, a diisocyanate, preferably a trifunctional polyisocyanate having a biuret and / or isocyanurate structure starting from hexamethylene diisocyanate can be used. The substance has weather resistance, chemical resistance and heat resistance, and is particularly effective for weather resistance. In addition to the above substances, diisophorone diisocyanate, diphenylmethane diisocyanate, bis (methylcyclohexyl) diisocyanate, toluene diisocyanate and the like can also be used.

  As the polyol, an oligomeric water-absorbing polyol can be used in order to develop anti-fogging property due to water absorption in the coating film. The water-absorbing polyol has the property of allowing water to adjoin the cross-linking of the molecule, and the hydroxyl group in the molecule reacts with the isocyanate group of the isocyanate prepolymer to form a urethane bond, thereby giving the urethane resin a water-absorbing property. Can be introduced. The water-absorbing polyol may have water-soluble properties.

  In order for the film to exhibit the antifogging effect due to water absorption, the amount of water-absorbing polyol used is adjusted so that the water absorption at the time of water absorption saturation of the film is 15% by weight or more. It is preferable to use an appropriate amount of the water-absorbing component derived from polyol. The water-absorbing component may be derived from an oxyalkylene-based polyol, preferably has an oxyethylene chain, an oxypropylene chain, etc., and particularly preferably has an oxyethylene chain excellent in water absorption.

  Further, if the water absorption is too high, the water resistance, hardness, abrasion resistance and the like of the coating tend to be low. Therefore, the water absorption of the coating is preferably adjusted to 30% by weight or less.

  The oxyalkylene polyol preferably has a number average molecular weight of 400 to 5,000. When the number average molecular weight is less than 400, the ability to absorb water as bound water becomes low, and when the average molecular weight exceeds 5000, the strength of the coating tends to decrease. In view of water absorption and film strength, the average molecular weight is more preferably 400-4500. As the polyol, an oxyethylene / oxypropylene copolymer polyol, polyethylene glycol or the like can be used. When polyethylene glycol is used, the number average molecular weight is set to 400 to 400 in consideration of water absorption and the strength of the resulting film. 2000 is preferable.

  As the polyol, in addition to the water-absorbing polyol, a hydrophobic polyol, a short-chain polyol having a number average molecular weight of 60 to 200, and the like can be used. The hydrophobic polyol has both flexibility and scratch resistance, and it is difficult to reduce the water absorption function and hydrophilic function of the film, and as a result, the water resistance and abrasion resistance of the film can be improved. It is preferable to use a polyester polyol having a number average molecular weight of 500 to 2000 or an acrylic polyol having an average molecular weight of 2000 to 4000.

  In the case of a polyester polyol, when the number average molecular weight is less than 500, the coating film becomes too dense and the wear resistance tends to decrease. On the other hand, if it exceeds 2000, the film formability of the coating agent deteriorates and it becomes difficult to form a coating film. In consideration of the denseness of the resulting film, the polyol preferably has 2 or 3 hydroxyl groups. As the polyester polyol, any of polycarbonate polyol, polycaprolactone polyol, and a mixture thereof can be used.

  In the case of an acrylic polyol, if the number average molecular weight is less than 2000, the wear resistance of the coating tends to decrease, and if it exceeds 4000, the coating property of the coating agent tends to be poor and the coating tends to be difficult to form. In consideration of the denseness and hardness of the resulting film, the polyol preferably has 3 or 4 hydroxyl groups.

  Hydrophobic components derived from these hydrophobic polyols are introduced so that the water absorption rate of the coating is in the above-mentioned range, preferably, when the pencil hardness of the coating obtained in accordance with “JIS K5400” is saturated with water absorption of the coating, Preferably, it is introduced so as to be HB to F.

  Moreover, the component derived from a short-chain polyol has the effect of increasing the curability of the coating agent, increasing the strength of the coating film, and reducing the static friction coefficient of the coating surface. The short chain polyol preferably has 2 or 3 hydroxyl groups. When the hydroxyl group is 1, the short-chain polyol does not become a skeleton component of the film, so that the film becomes fragile. When it exceeds 3, the reactivity is too active and the coating agent tends to be unstable.

  Short chain polyols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5 -Pentanediol, 2-butene-1,4-diol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, glycerin, 2- Alkyl polyols such as ethyl-2- (hydroxymethyl) -1,3-propanediol, 1,2,6-hexanetriol, 2,2′-thiodiethanol, alkanolamines such as diethanolamine, triethanolamine, and the like. They can be used alone or as a mixture or A copolymer or the like having a molecular weight not exceeding 200 can be used, and the component derived from the short-chain polyol can be introduced so that the water absorption rate of the film and the contact angle of the water droplet are within the above-described ranges. The short-chain polyol is preferably 2.5% by weight to 10% by weight with respect to the total amount of the water-absorbing urethane component.

  The water-absorbing film has a low anti-fogging property at a water absorption rate of 10% by weight or less, and therefore becomes clouded only by applying a small amount of water vapor (exhaled air). On the other hand, when the amount is 40% by weight or more, the practical strength is insufficient, so the range of 10 to 40% by weight is preferable. Moreover, since the amount of water absorption is small when the film thickness is thin, it becomes cloudy just by applying a very small amount of water vapor (exhaled air) as in the case of a water absorption rate of 10% by weight or less. If the film thickness is large, it is difficult to obtain a uniform film thickness and optical distortion is likely to occur. Therefore, the film thickness is preferably 1 to 50 μm.

  In step 2, the glass substrate on which the coating film is formed, the interlayer film for laminated glass, and another glass substrate are laminated in this order, and laminated glass is formed by heating. Here, as an interlayer film for laminated glass, a commercially available one may be used. For example, a plasticized polyvinyl acetal resin (mainly representative is polyvinyl butyral (PVB). ), Modified products mainly composed of ethylene-vinyl acetate copolymer (EVA), modified products composed mainly of ethylene- (meth) acrylic acid ester copolymer, urethane-based polymers, vinyl chloride polymers. A modified product or the like is used. The thickness of the intermediate film is preferably 0.1 or more, and more preferably 0.2 mm or more from the handling of the intermediate film when producing a laminated glass. The upper limit is not particularly limited, but is preferably 2 mm, and more preferably 1 mm.

  Moreover, as an example of another glass substrate, soda lime silicate glass is used as a representative one. The glass is a glass that is usually used for automobiles, buildings, industrial glasses, and the like, and is produced by a float method, a duplex method, a roll-out method, or the like.

  As glass types, it can be used for various colored glasses such as clear, green and bronze, various functional glasses such as UV, IR cut glass and electromagnetic shielding glass, netted glass, low expansion glass, zero expansion glass and fireproof glass. Various glass products such as glass, tempered glass and the like, mirrors produced by the silvering method or vacuum film-forming method, and flat plates and bent plates can be used. The plate thickness is not particularly limited, but is preferably 1.0 mm or more and 10 mm or less, and is preferably 1.0 mm or more and 5.0 mm or less for vehicles. You may use the glass substrate in which the film was formed.

  In the process of forming laminated glass in Step 2, first, the glass substrate on which the film produced in Step 1 is formed, the interlayer film for laminated glass, and another glass substrate are laminated. At this time, it is necessary that the coating is not directed toward the intermediate film. This laminated state is hereinafter referred to as a laminated body. In order to adhere the interlayer film for laminated glass and the glass substrate surface in the laminate, heating is performed. At this time, in order to perform deaeration at the interface between the interlayer film for laminated glass and the surface of the glass substrate, the laminate is preferably placed under reduced pressure.

An example of step 2 is as follows. It is preferable to introduce the laminate into a vacuum bag and deaerate the bag by reducing the pressure to 4 × 10 ³ Pa or less at room temperature. Regarding the time for depressurization at room temperature, it is preferable to hold at room temperature for about 10 minutes after reaching a predetermined pressure.

  Next, the vacuum bag is transferred to an oven while maintaining the reduced pressure state, and heat treatment is performed for a predetermined time. The temperature at this time is +20 to + 50 ° C. of the flow starting temperature of the interlayer film for laminated glass, and the heating time is not particularly specified, but preferably it is about 10 to 60 minutes and cooled to room temperature. The work (generally a leak) for bringing the inside of the vacuum bag into the atmospheric pressure state may be performed immediately after the completion of heating, but bubbles may enter the intermediate film, so it is performed after cooling to room temperature or during cooling. May be.

  Step 2 is not limited to the above-described vacuum bag method, but may be a method using a vacuum ring method, a roll pressure bonding method, or the like. Further, after degassing at a low temperature in advance using the method described above, an autoclave is used thereafter. May be finished by heating.

  In step 2, a sheet body that does not exhibit adhesion to the coating formed on the glass substrate before heating the laminate is stacked on the coating formed on the glass substrate, and then laminated into glass. Also good. By loading the sheet on the film, dust and dirt are prevented from adhering to the film, and the cleaning of the film after Step 2 required when dust and dirt adhere can be saved. .

  Examples of the sheet include a polyethylene terephthalate (PET) film or a fluororesin film such as Teflon (registered trademark). The thickness of the sheet is preferably 0.05 mm or more and 0.5 mm or less in consideration of handleability.

  In step 3 after vitrification, a coating solution containing a surfactant is applied to the surface of the coating in order to support the surfactant in the water-absorbing coating. A surfactant used in the solvent of the coating solution is dissolved and absorbed in the coating in a state where the surfactant is dissolved, separated from the surfactant in the evaporation process, and released to the outside of the coating. Water, alcohols, ketones, ethers, esters, and polyhydric alcohols are preferably used.

  As water, purified water, ion-exchanged water or the like can be used. As alcohols, isopropyl alcohol, ethyl alcohol, and the like can be used. As ketones, acetone, acetone alcohol, acetoin, diacetone alcohol, benzoin and the like can be used.

  Examples of ethers that can be used include tetrahydrofuran, isopropyl ether, and ethyl ether. As the esters, isobutyl acetate, butyl acetate and the like can be used. Examples of polyhydric alcohols that can be used include ethylene glycol, ethylene glycol diacetate, and ethylene glycol diethyl ether.

  The coating method of the coating solution containing the surfactant is a roll coating method, a dip coating method, a brush coating method, a spray coating method, a bar coating method, a knife coating method, a die coating method, a spin coating method, or a curtain coating method. Any method in accordance with a common method such as law or hand painting may be used. It is applied to a substrate and allowed to dry naturally at room temperature for about 24 hours, or heated at 30 to 50 ° C. for 10 to 60 minutes to dry the solvent in the coating solution.

  The surfactant includes a nonionic surfactant having an oxyethylene chain, a mixture of a nonionic surfactant having an oxyethylene chain and an amphoteric surfactant, or a surfactant having an isocyanate-reactive group. It is preferred that an agent is used.

  Nonionic surfactants having an oxyethylene chain include polyoxyethylene lauryl ether, polyoxyethylene tridecyl ether, polyoxyethylene alkyl ether, polyoxyethylene oleyl ether, polyoxyethylene cetyl ether, polyoxyethylene cured castor. Oils, polyethylene glycol monooleate, polyethylene glycol dioleate, polyethylene glycol monostearate, ethylene glycol distearate, polyethylene glycol distearate, and the like can be used.

  Examples of amphoteric surfactants include lauryl dimethylamine oxide, coconut oil alkyldimethylamine oxide, myristamidopropyl hydroxysulfobetaine, laurylhydroxysulfobetaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolium betaine N-lauroyl-N′-carboxymethyl-N′-hydroxyethylethylenediamine sodium, coconut oil alkylbetaine, lauryldimethylaminoacetic acid betaine, lauryldimethylaminoacetic acid betaine, and the like can be used.

  In addition, when using a mixture of a nonionic surfactant having an oxyethylene chain and an amphoteric surfactant, the ratio is such that the amphoteric surfactant is weight to the nonionic surfactant. The ratio is 0.2 to 5 times, preferably 0.3 to 3 times, and more preferably 0.5 to 2 times.

  When using a surfactant having an isocyanate-reactive group such as ricinoleamidopropylethyldimonium ethosulphate, the diisocyanate of the compound having an NCO group, preferably hexamethylene diisocyanate, in the coating solution containing the surfactant Bifunctional and / or trifunctional polyisocyanates having an isocyanurate structure can be used. The substance has weather resistance, chemical resistance and heat resistance, and is particularly effective for weather resistance. In addition to the above substances, if diisophorone diisocyanate, diphenylmethane diisocyanate, bis (methylcyclohexyl) diisocyanate, toluene diisocyanate, etc. are also introduced, the compound and the surfactant are added after the surfactant is applied to the film. A reacted product is produced. The product is preferable because it is easily supported on the film. In this case, it is preferable to use ketones as the solvent.

(1) Production of anti-fogging laminated glass Example 1
1. Implementation of Step 1 A film-forming coating solution was prepared on the surface of the glass substrate by the following procedure. 0.95 g amount of polycaprolactone diol having an average molecular weight of 1250 (trade name “Placcel L212AL” manufactured by Daicel Chemical Industries), 0.47 g amount of primary ethylene glycol (manufactured by Kishida Chemical Co., Ltd.), and an average molecular weight of 1000 that provides water absorption to the resin Of polyethylene glycol was mixed with an amount of 3.32 g.

  4.26 g of hexamethylene diisocyanate burette type polyisocyanate (manufactured by Sumitomo Bayer Urethane Co., Ltd., trade name “N3200”) is added to and mixed with the mixture obtained above, and diacetone alcohol is added so that the total components are 30% by weight To prepare a film-forming coating solution.

  The coating solution is spin coated on the entire surface of the mirror substrate (thickness 5 mm, size 300 mm × 600 mm) opposite to the reflective layer side obtained by silvering a soda lime silicate glass plate (float glass plate glass). Applied. Thereafter, a film made of a urethane resin having water absorption was formed on the substrate by heating at 150 ° C. for 60 minutes.

  A primer layer is formed on the glass substrate opposite to the reflective layer side in order to improve the alkali resistance and adhesion of the article. The primer layer is obtained by the following procedure. 1% by weight of γ-aminopropyltriethoxysilane (LS-3150, manufactured by Shin-Etsu Silicone) with denatured alcohol (Echinen F-1, manufactured by Nippon Alcohol Sales) consisting of 90% by weight ethanol and 10% by weight isopropyl alcohol. The zirconium oxychloride octahydrate, which is a hydrolyzable zirconium compound, was prepared in such a manner that the zirconium amount of the zirconium compound was 0.0008 times by weight with respect to the silicon amount of the silicon compound. To obtain a primer layer having a pH of 1.5. Then, the liquid is applied by wiping the surface of the glass substrate with a wiper (trade name “Bencot”, model M-1, 50 mm × 50 mm, manufactured by Ozu Sangyo) made of cellulose fiber that has absorbed the liquid. After drying in a state, a primer layer is obtained by washing the coated surface with tap water using a wiper.

2. Implementation of Step 2 As the interlayer film for laminated glass, a resin mainly composed of a saponified ethylene-vinyl acetate copolymer having a thickness of 0.4 mm (trade name Mersen G7055 manufactured by Tosoh Nikkemi Co., Ltd.) was used.

  The intermediate film was sandwiched between one float plate glass having a thickness of 5 mm and a size of 300 mm × 600 mm and the mirror substrate on which the film obtained in Step 1 was formed, and a laminate was formed so that the film became the outer surface. Next, a PET film (Toyobo Co., Ltd., trade name: Toyobo Ester Film E5001) having a thickness of 0.1 mm and a size of 300 mm × 600 mm was loaded on the coating, and the laminate was introduced into a vacuum bag.

After reducing the pressure for 10 minutes to 4 × 10 ³ Pa or less, the vacuum bag containing the laminate was transferred to an oven and heated for 40 minutes so that the temperature of the intermediate film became 110 ° C. Thereafter, the vacuum bag was leaked, the laminate was cooled to room temperature, and the PET film was peeled from the coating.

3. Implementation of Step 3 Zwitterionic surfactant (manufactured by Toho Chemical Industry, product name “Softamin L”, surfactant concentration 30%) 3.0 g, polyethylene glycol type nonionic surfactant (manufactured by Toho Chemical Industry) The product name “Pegnol TH-8”, surfactant concentration 100%) 1.0 g amount and 6.0 g amount of purified water were mixed to prepare a coating solution having a surfactant. And by wiping the urethane resin film of the antifogging laminated glass obtained in 2 above with a cotton cloth soaked with the coating liquid, the coating liquid was applied to the film, and then allowed to stand for 24 hours, An antifogging laminated glass was obtained.

Example 2
Except that the PET film was not loaded on the laminate in Step 2, the same procedure was performed to obtain an antifogging laminated glass.

Comparative Example A laminated glass obtained without performing Step 3 was used as a comparative example.
(2) Evaluation of anti-fogging laminated glass By evaluating the following items, the characteristics of the anti-fogging laminated glass were evaluated. The evaluation results are shown in Table 1.
-Evaluation item 1; Appearance inspection was performed on the surface.
Evaluation item 2: Visual evaluation of an image reflected in a mirror when exhaled air is applied to a film.

Claims (3)

This is a method for producing anti-fogging laminated glass, which comprises a glass substrate surface having a water absorption of 10 to 40% by weight of oxyethylene chains.
Step 1 of forming a film made of a retane resin,
A step 2 of laminating the glass substrate on which the coating is formed, an interlayer film for laminated glass, and another glass substrate in order and forming a laminated glass by heating; and a step 3 of supporting a surfactant in the coating,
A process for producing an anti-fogging laminated glass characterized in that, in Step 3, a coating liquid containing a surfactant is applied to the surface of the coating so that the surfactant is supported in the coating.   The surfactant is a nonionic surfactant having an oxyethylene chain, a mixture of a nonionic surfactant having an oxyethylene chain and an amphoteric surfactant, or a surfactant having an isocyanate-reactive group. The method for producing an antifogging laminated glass according to claim 1, wherein:   3. In the step 2, the sheet body that does not exhibit adhesion to the coating before the heating is stacked on the coating formed on the glass substrate, and then laminated glass is formed. The manufacturing method of the anti-fogging laminated glass of description.