JPH028049A - Anti-fogging heat-insulating sheet - Google Patents

Abstract

PURPOSE:To obtain an anti-fogging heat-insulating sheet having excellent antifouling properties by providing a hydrophilic film cross-linked by irradiation with electron rays on a surface of a heat-insulating film or sheet. CONSTITUTION:A hydrophilic film 5 is provided on a heat-insulating sheet comprising, for example, a core material 3 disposed in a stripe pattern between two transparent films 1, 2, with an air layer 4 formed between the stripes of the core material 3. To provide the hydrophilic film, for example, a composition containing a polymer, a hydrophilic monomer and, optionally, a surface active agent is conditioned to an appropriate viscosity by dilution with a solvent, the resultant material is applied to a surface of the heat-insulating sheet, and is dried by heating by a drier or the like to evaporate off the solvent. Upon irradiation with electron rays, the polymer is made to be cross-linkable, and the hydrophilic monomer is cross-linked on the polymer in the mode of graft polymerization or block polymerization, whereby the hydrophilic film is formed on the heat-insulating sheet.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a sheet having antifogging properties and heat insulating properties, and is particularly suitable for use on window glass, etc. in order to prevent condensation caused by temperature differences between indoors and outdoors. This invention relates to an anti-fog heat insulating sheet to be attached to.

[Prior Art and Problems to be Solved by the Invention] When there is a large temperature difference between indoors and outdoors during winter, etc., a phenomenon occurs in which condensation forms on the indoor side of windows that do not have a heat insulating effect. If such an environment that causes condensation continues for a long time, the water droplets generated by the condensation will become water droplets, forming puddles on the window bars and rails, causing corrosion and mold on the wall covering, and causing damage to the window if it freezes. Problems such as difficulty in opening and closing may occur.

In order to prevent dew condensation that causes such problems, various films and sheets are known that reduce the temperature difference between the indoor temperature and the window glass surface temperature on the indoor side due to their heat insulating effect.

By installing these conventional heat insulating films and sheets on the indoor side of window glass, it is possible to prevent condensation to some extent, but there are limitations in terms of the window's ability to open and close, transparency, and visibility. Therefore, the film thickness and material are limited. Therefore, if there is a large temperature difference between indoors and outdoors, a sufficient heat insulating effect cannot be obtained, and fine water droplets (clouding) are formed on the indoor surface, resulting in a problem in that transparency and visibility are significantly reduced.

Furthermore, this type of anti-condensation film and sheet also has the problem that dust and dirt tend to adhere to the surface due to the generation of static electricity.

In view of the above problems, an object of the present invention is to solve the problems of the prior art described above, to prevent the generation of fine water droplets (fogging) due to dew condensation, and to provide an anti-fog heat insulating sheet with excellent stain resistance. It is to provide.

[Means to solve the problem]

As a result of intensive research in view of the above object, the present inventors discovered that it is sufficient to form a hydrophilic film on the surface of a heat insulating film or sheet, and came up with the present invention.

That is, the antifogging heat insulating sheet of the present invention is characterized in that a hydrophilic film crosslinked by electron beam irradiation is formed on the surface of the heat insulating film or sheet.

The present invention will be explained in detail below.

Examples of the heat insulating film or sheet used in the present invention include (a) those having a low thermal conductivity layer, and (d) those having a heat insulating effect by reflecting or blocking heat rays (infrared rays). .

As the former low thermal conductivity layer, a gas layer can be mentioned, and an air layer is particularly optimal in terms of cost.

Examples of heat insulating sheets having a low thermal conductivity layer (a) include those shown in FIGS. 1 to 4. FIG. 1 shows a structure in which a hydrophilic film 5 is formed on a heat insulating sheet in which a core material 3 is provided in stripes between two transparent films 1.2 and an air layer 4 is formed between them. FIG. 2 shows two films 11.
Between 120 and 120, a corrugated or accordion-shaped film 13
is laminated to form an air layer 14 on a heat insulating sheet,
A hydrophilic film 15 is shown. Further, FIG. 3 shows a transparent film 22 on a convex portion 23 of a transparent sheet 21 made of soft plastic and having regular uneven vertical stripes.
A hydrophilic film 25 is formed on a heat insulating sheet in which an air layer 24 is formed by laminating the above. Furthermore, Figure 4 shows 2
Mesh sheet 33 between transparent films 31 and 320
is laminated to form an air layer 34 on a heat insulating sheet,
A hydrophilic film 35 is shown.

On the other hand, a heat insulating sheet using a sheet that reflects or blocks heat rays has a structure shown in FIG. 5, for example.

In FIG. 5, 41 is a so-called heat reflective film (sheet), and 42 is a hydrophilic film. Examples of heat reflective films (sheets) include the following.

■The base film or sheet may contain thin films of metals (including vapor-deposited films) such as titanium, silver, aluminum, gold, platinum, zinc, copper, etc., or transparent materials such as metal alkoxide compounds, organotitanium compounds, organosilicon compounds, etc. A laminate made by laminating high refractive index dielectric layers.

■A laminate consisting of a transparent thin film layer containing a specific metal or a metal thin film layer coated with a protective film layer of silicon oxide, and a transparent film such as a transparent plastic film such as polyester or polyethylene (Jikai 1983- (See Publication No. 14036).

■A light-transmitting sheet made by laminating an organic polymer film on a Fabry-Perot filter that transmits only light of a specific wavelength.

These heat insulating films or sheets are required to have transparency and visibility since the anti-fog heat insulating sheet of the present invention is mainly used for window glass, etc., but they are required to have transparency and visibility. When applied, transparency and visibility are not necessarily required.

The hydrophilic membrane in the present invention is basically made by crosslinking a polymer with a hydrophilic monomer or the like by irradiating it with an electron beam, and
It is made of a material containing a surfactant if necessary. A specific combination is (a) polymer + hydrophilic monomer (b) polymer + hydrophilic monomer + surfactant; (c) polymer + hydrophilic monomer + surfactant;
Polymer ten hydrophilic things? - crosslinking monomers (d) polymers, lignophilic monomers, crosslinking monomers, surfactants, (e) polymers, hydrophilic crosslinking monomers, (f) polymers, hydrophilic crosslinking monomers, and surfactants; ) Polymer, ten woody monomers, ten hydrophilic crosslinking monomers, and (h) polymer, ten woody monomers, and hydrophilic crosslinking seven, ten surfactants. In all of the above combinations, the polymer can be either functional or non-functional.

As will be described later, it is not necessary that the surfactant be added to the hydrophilic film in sufficient amount from the beginning, as long as it becomes sufficient after applying the solution containing the surfactant. The above combinations of (b), (d), (f), and (ch) should be understood as such.

As the non-functional polymer, polyacrylic acid alkyl ester, polymethacrylic acid alkyl ester, polyurethane, polyester, polyamide, polyvinyl acetate, polyvinyl chloride, polystyrene, polyacrylonitrile, polyvinylpyrrolidone, etc. can be used.

A hydrophilic group may be introduced into the non-functional polymer in advance to improve compatibility with the hydrophilic monomer. This includes monomers with hydrophilic groups (hydrophilic monomers), which will be described later.
A copolymer with The ratio of the hydrophilic monomer to the non-functional polymer is 50 mol% or less, and if it exceeds this, the water resistance of the resulting membrane will decrease.

Furthermore, derivatives of polyvinyl alcohol such as partially saponified polyvinyl alcohol, polyvinyl butyral, and polyvinyl acetal, and cellulose derivatives such as nitrocellulose, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, and hydroxypropyl cellulose can also be used. .

On the other hand, a functional polymer is a polymer having a functional group that causes a crosslinking reaction by ionizing radiation, and examples of the functional group include the following.

Acryloyl group -QC-C=CH2 CH3 methacryloyl group 10C-C=CH2 a Li Group -CH2-CH=CH.

E Bo Ki group -CH-CH.

＼ 1 The ratio of functional groups is preferably 1 per 300 to 10,000 molecular weight of the polymer, and 1 per 10,000 molecular weight.
When the ratio is less than 1, there is almost no crosslinking effect due to the functional group, and when the ratio exceeds 1 per 300 molecular weight, the crosslinking density becomes too high.

Examples of functional polymers include urethane acrylate, polyester acrylate, epoxy acrylate, etc., and acrylic chloride or 2-hydroxyethyl acrylate and diisocyanate on the hydroxyl group of a copolymer of acrylic acid alkyl ester and 2-hydroxyethyl acrylate. Copolymers with acryloyl groups introduced by adding a 1:1 adduct of acrylic acid, copolymers with glycidyl methacrylate added to the carboxyl groups of copolymers of acrylic acid alkyl ester and acrylic acid, and copolymers with glycidyl methacrylate added to the carboxyl groups of copolymers of acrylic acid alkyl ester and acrylic acid. Acrylic acid chloride or acrylic acid-
A 1:1 adduct of 2-hydroxyethyl and diisocyanate can be used.

The above-mentioned polymer may be in the form of an oricomer, but from the viewpoint of film-forming properties, the molecular weight is preferably from 1,000 to 300,000 (weight average).

Hydrophilic monomers include hydroxyl groups, carboxyl groups (metal salts),
Amide group, imide group, sulfone group, ammonium base,
A monomer containing a hydrophilic group such as a phosphoric acid group, such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, etc.
Hydroxyethyl, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, acrylic acid,
Methacrylic acid, metal acrylate, metal methacrylate, acrylic acid dimer, acrylamide, methacrylamide, dimethylamine propyl acrylamide, dimethylaminopropyl methacrylamide, N-acryloylmorpholine, N-methacryloylmorpholine, N-
Methylolacrylamide, N-methylolmethacrylamide, t-butylacrylamide, t-butylmethacrylamide, N-methoxymethylacrylamide, N-
Ethoxymethylacrylamide, N-n-butoxyacrylamide, N,N-dimethylacrylamide, N,N
-dimethylaminopropylacrylamide, N,N-dimethylaminopropylmethacrylamide, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, glycerol monomethacrylate, 2-acrylamide 2-methylpropanesulfonic acid, methacrylamidepropyltrimethylammonium chloride, methacryloyloxyethyl Trimethylammonium chloride, mono (2-methchloroyloxyethyl) acid phosphate and the like can be mentioned.

Crosslinking monomers include acryloyl group, methacryloyl group,
This monomer has two or more groups that easily become radicals when irradiated with electron beams, such as allyl groups and epoxy groups, and it crosslinks with both the backbone polymer and the hydrophilic monomer, so it improves the crosslinking density of the entire membrane and strengthens the membrane. and to prevent unreacted hydrophilic monomers from remaining. Such crosslinkable monomers include ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, 1,6-hexanethiol dimethacrylate, glycidyl methacrylate, neopentyl glycol dimethacrylate, tetraethylene glycol dimethacrylate, 2,2-bis[4(acrylic) Roxyjetoxy)phenyl]propane, 2.2-bis(4-(methacryloxyjethoxy)phenyl)propane, 2.2-bis(4-
(acryloxypolyethoxy)phenyl]propane, 2
．． Bifunctional monomers such as 2-bis[4-(methacryloxypolyethoxy)phenyl]propane, trifunctional monomers such as trimethylolpropane trimethacrylate, other polyfunctional monomers such as tetramethylolmethanetetraacrylate, dipentaerythritol hexaacrylate, etc. can be mentioned.

Hydrophilic crosslinking monomers include hydroxyl groups, carboxyl groups (metal salts), amide groups, imide groups, sulfonic acid groups (metal salts),
It is a monomer having a hydrophilic group such as an ammonium base or a phosphoric acid group and two or more crosslinkable functional groups that easily become radicals by electron beam irradiation, such as an acryloyl group, a methacryloyl group, an allyl group, or an epoxy group.

Examples of such hydrophilic crosslinkable monomers include those having a hydroxyl group such as glycerol di(meth)acrylate and glycerol methacrylate acrylate, ethylene glycol, diglycidyl ether di(meth)acrylate, and polyethylene glycol diglycidyl ether di( meth)acrylate, polypropylene glycol diglycidyl ether di(meth)acrylate, neopentyl glycol diglycidyl ether di(meth)acrylate, glycerin diglycidyl ether di(meth)acrylate,
1 of diol diglycidyl ether such as meth)acrylate, hisphenol Δ diglycidyl ether di(meth)acrylate, trimethylolpropane triglycidyl ether di(meth)acrylate and acrylic acid:
2-adduct, pentaerythritol mono(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate,
dipentaerythritol mono(meth)acrylate,
Pentaerythritol derivatives such as diventaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, methylene bis(meth)acrylate
Acrylamide, acrylamide/glyoxal adduct, acrylamide/methylethylene urea condensate, 1°3.5-)lyacryloylhexahydro S-triazine, N,N-diallylacrylamide, acrylamide/
Methylolmelamine condensate, acrylamide/methyloltriazone condensate, acrylamide/methylolhydantoin condensate, acrylamide/methylolurea, N
and acrylamide derivatives such as N-diallylacrylamide.

Hydrophilic membranes used in the present invention can also contain surfactants. The surfactant has the effect of imparting dew-preventing properties (anti-fogging properties) by gradually exuding from the hydrophilic film to the surface. Any anionic, nonionic, or cationic surfactant can be used as long as it has good compatibility with the composition consisting of the above-mentioned components constituting the hydrophilic layer.

Examples of anionic surfactants include fatty acid salts, alkyl sulfate ester salts, alkylbenzene sulfonates, alkylnaphthalene sulfonates, dialkyl sulfosuccinate ester salts, alkyl phosphate ester salts, naphthalene sulfonic acid-formalin condensates, and polyoxine ethylene. There are alkyl sulfate ester salts, etc. Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, polyquine ethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, and polyoxyethylene alkyl amine. , glycerin fatty acid ester,
Examples include oxyethylene-oxypropylene block polymers, and examples of cationic surfactants include alkyl amines and quaternary ammonium salts.

When forming the hydrophilic membrane used in the present invention, polymer 10
The wood-philic monomer is added in an amount of 5 to 300 parts by weight per 0 parts by weight. If it is less than 5 parts by weight, sufficient hydrophilicity will not be imparted, and if it exceeds 300 parts by weight, the water resistance of the membrane will decrease. The preferred content of hydrophilic monomer is 20 to 250 parts by weight.

The amount of crosslinking monomer is 1 to 300 per 100 parts by weight of polymer.
Parts by weight. If it is less than 1 part by weight, the crosslinking of unreacted hydrophilic monomers will be insufficient, and if it exceeds 300 parts by weight, the crosslinking density of the entire membrane will be too high. Especially when the polymer has no functional groups, the content of crosslinking monomers is between 5 and 3
It is preferably 0.00 parts by weight, more preferably 5 to 200 parts by weight. When the polymer has a functional group, the content of the crosslinkable monomer is preferably 1 to 200 parts by weight, more preferably 5 to 100 parts by weight.

Hydrophilic crosslinking monomer per 100 parts by weight of polymer
~200 parts by weight. If it is less than 1 part by weight, sufficient hydrophilicity and crosslinking properties will not be imparted, and if it exceeds 200 parts by weight, the water resistance of the membrane will decrease and the crosslinking density will become too high. The preferred content of hydrophilic crosslinking monomer is 1 to 10
It is 0 parts by weight.

A surfactant is not necessarily required, but when added, the amount is 200 parts by weight or less per 100 parts by weight of the polymer. 20
If it exceeds 0 parts by weight, too much surfactant leaches out. The preferred content is 1 to 100 parts by weight.

When forming a hydrophilic film, a suitable solvent may be added to the composition consisting of an appropriate combination of the above components.

Solvents are preferred for forming the hydrophilic film of the present invention because they not only adjust the fluidity of the composition but also have the effect of lifting the hydrophilic film onto the surface of the coating film. Solvents that can be used include alcohols such as methanol, ethanol, impropatol, methyl cellosolve, and ethyl cellosolve, ethers such as tetrahydrofuran, ketones such as methyl ethyl ketone, acetone, and methyl isobutyl ketone, ethyl acetate, and butyl acetate. and aromatic hydrocarbons such as toluene and xylene, and mixed solvents thereof.

The amount of solvent added varies depending on the film formation method, but when forming a coating film by coating, the solid content of the composition should be 5 to 50% by weight, preferably 5 to 30% by weight. . -For boat fishing, the amount of solvent added is 6000 per 100 parts by weight of polymer.
Part by weight or less.

Using the above composition, a hydrophilic film can be formed on a heat insulating film or sheet by the following method.

First, if the composition does not contain a solvent, adjust the composition to an appropriate viscosity by heating or other methods, and then apply a roll coating method such as the gravure reverse method, three-reverse method, gravure direct method, or four-reverse method. , to be applied onto the film. As the film, a transparent plastic film is generally used, and as the material, polyester, polyethylene, polypropylene, polycarbonate, polyacrylate, polystyrene, polyamide, polyimide, polyvinyl chloride, etc. can be used.

After the composition is applied to the film, the coated side is laminated to a heat insulating film or sheet and irradiated with an electron beam.

As the irradiation method, any method such as an electron curtain method or a beam scanning method can be used. Irradiation with electron beams makes the polymer crosslinkable regardless of the presence or absence of functional groups, and the woodphilic monomer and hydrophilic crosslinkable monomer are crosslinked to the polymer in the form of graft polymerization or block polymerization.

This point is markedly different from crosslinking by ultraviolet irradiation.

The energy of the irradiated electron beam is about 150 to 200 keV, and the irradiation amount varies depending on the composition of the composition, the desired degree of crosslinking density, etc. The more functional groups there are in the polymer, the lower the irradiation dose is required, and the higher the crosslinking density, the higher the irradiation dose.

In particular, when a surfactant is contained, controlling the irradiation amount is important because if the crosslinking density is too high, the exudation will be insufficient and the dew condensation prevention (anti-a) effect will be reduced.

From the above, the irradiation amount is generally 0.5 to 2Q Mrad, and if it is less than 0.5 Mrad, unreacted monomer may remain, and if it exceeds 20 Mrad, the crosslinking density becomes too high.

After forming a hydrophilic film by electron beam irradiation, the film is peeled off and transferred to a heat insulating film or sheet.

Moreover, the film can also be used as a protective film without being peeled off until the time of construction.

Next, if the composition contains a solvent, the viscosity is adjusted to an appropriate level by dilution with a solvent, etc., and then by a roll coating method such as the gravure reverse method, three-reverse method, gravure direct method, four-reverse method, etc. Applied on the surface of an insulating film or sheet.

The coating film of the composition formed on the heat insulating film or sheet is dried while being heated with a dryer or the like in order to evaporate and remove the solvent. If the heating temperature is too high, problems such as evaporation of monomers and deformation of the heat insulating film or sheet will occur, so the maximum heating temperature is about 140°C.

This coating film is then irradiated with electron beams in the same manner as described above to form a hydrophilic film on the heat insulating film or sheet. Depending on the application, a transparent plastic film may be laminated on top of the hydrophilic film to form a protective film.

If it is difficult to apply the composition onto a heat insulating film or sheet, an anti-fog layer can also be formed by applying the composition onto a transparent plastic film and then laminating it.

Furthermore, if the adhesion between the hydrophilic film and the heat insulating film or sheet is not sufficient, the hydrophilic film can be transferred by subjecting the hydrophilic film to an adhesion-facilitating treatment and laminating the film or sheet.

Further, when considering the workability of the heat insulating sheet having dew condensation prevention (antifogging) performance in the present invention, it is convenient to form an appropriate adhesive layer on the side opposite to the dew condensation prevention layer.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.
It goes without saying that the present invention is not limited to these.

Example 1 (a) As a heat insulating sheet, a window glass heat insulating sheet manufactured by Nitoms was used, in which a striped core material was provided between two transparent polyethylene films, and an air pocket was formed between them, and (b)
) As a heat insulating film, the transparent heat ray reflective film Reftil (trade name) manufactured by Konjin (polyester base, 25 μm
119 [), apply the following composition to one side of each using a roll coater, and dry with a dryer to a thickness of 5.
A hydrophilic film of μm was formed.

Acrylic polymer solution: 300 parts by weight 2-hydroxyethyl methacrylate (hydrophilic monomer) 70 parts by weight Pentaerythritol triacrylate (hydrophilic crosslinking monomer) 10 parts by weight Methyl ethyl ketone (solvent) 300 parts by weight The acrylic polymer solution is prepared by the following procedure. I went there. That is, 700 parts by weight of methyl methacrylate, 390 parts by weight of 2-hydroxyethyl methacrylate, 1.5 parts by weight of azobisisobutyronitrile, and 2210 parts by weight of methyl ethyl ketone were equipped with a reflux tube and a stirrer, and the atmosphere was replaced with nitrogen. The mixture was placed in a separable flask and reacted at 85° C. for 5 hours in a N2 stream. Then add 1. azobisisobutyronitrile.
5 parts by weight were added and reacted for 3 hours. The resulting acrylic polymer solution had a concentration of 33% by weight and a weight average molecular weight (Mw) of 7°5×10′ as determined by gel permeation chromatography (GPC). Moreover, no monomer peak was observed.

Next, an electron curtain type EB device (manufactured by ESI)
The coating film was cured by irradiating it with a 175 keV electron beam at 5 Mrad.

The anti-fogging properties (anti-fog properties) of the two types of anti-fog heat insulating sheets obtained were evaluated by the following method.

(1) Breath test (to check whether cloudiness occurs with exhaled breath). O: No clouding occurred; X: Clouding occurred.

(2) Temperature Difference Test An indoor/outdoor temperature difference deterioration tester (B P-F M-1” made by Suga Test Instruments), which consists of two chambers separated by a glass plate, and can freely control the temperature and humidity of each chamber. After pasting an evaluation sample with an adhesive finish on the back, one room was kept at a constant temperature of 20°C and relative humidity of 60%, while the other room was subjected to a cycle of temperature and humidity fluctuations (relative humidity of 60%). %
, holding the temperature at −10° C. for 30 minutes, followed by holding at 20° C. for 2 hours) were repeated. Evaluation was performed by observing the cloudy state (transparency, clarity) for each cycle.

○ No clouding at all.

△ There is no cloudiness, but there is no clear visibility.

× Fine water droplets adhere to the entire surface, making it opaque.

Both types of anti-fog heat insulating sheets of the present invention were rated good in both (1) breath test and (2) temperature difference test.

Examples 2 to 1O Using each composition shown in Table 1, a hydrophilic film was formed on a heat insulating sheet in the same manner as in Example 1, and the same evaluation was performed. The results are shown in Table 1.

The urethane acrylate of Example 4 was prepared by the following procedure. That is, using the same apparatus as in Example 1,
Among them, butylene adipate (Niraporan N-457
0J Nippon Polyurethane > 650g, methyl ethyl ketone 300g, Inphoron diisocyanate) 444
g, and a solution of 1 g of dibutyltin dilaurate dissolved in 10 g of methyl ethyl ketone was added dropwise while stirring at 60°C. While stirring in a nitrogen stream for 5 hours, 232 g of 2-hydroxyethyl acrylate was added dropwise, and after the dropwise addition was completed, stirring was continued at 70°C for an additional 3 hours. The reaction was terminated when it was confirmed by infrared absorption spectrum that the peak of the -NGO group had disappeared. The weight average molecular weight (nw) of the obtained polymer was found to be 1700 by GPC.

Comparative example Window glass insulation sheet without a hydrophilic film on the surface layer (manufactured by Tom's ■) and transparent heat ray reflective film Reftil (manufactured by Teijin ■)
The same evaluation test as in Example 1 was conducted. The results are shown in Table 1, and both the sheet and film were rated poor in the breath test and temperature difference test.

(Note) (1) 7:3 (molar ratio) copolymer of methyl methacrylate and 2-hydroxyethyl methacrylate (2) Polymethyl methacrylate (3) 7:3 copolymer of methyl methacrylate and N,N-dimethylacrylamide Copolymer (4) 2-hydroxyethyl methacrylate (5) Criserol monomethacrylate (6) N-acryloylmorpholine (7) N,N-dimethylacrylamide (molar ratio)
8) Diethylene glycol dimethacrylate (9) Dipentaerythritol hexaacrylate α Q Tetraethylene glycol diacrylate Ql) Pentaerythritol acrylate (branch) Dipentaerythritol pentaacrylate α ■ Ethylene glycol diglycidyl ether diacrylate α O Methyl ethyl ethone α Double window glass Insulating sheet (manufactured by Tom's ■) α-opening transparent heat ray reflective film (manufactured by Teijin ■) Examples 11 to 15 New composition of hydrophilic film of Example 1 and Example 3.4.6.9 shown in Table 1 After adding each of the surfactants shown in Table 2, a hydrophilic membrane containing the surfactant was obtained in the same manner as in Example 1.

These hydrophilic membranes were evaluated in the same manner as Examples 1-10. The results are shown in Table 2.

〔Effect of the invention〕

The antifogging heat insulating sheet of the present invention has a hydrophilic film in which a hydrophilic monomer and/or a hydrophilic crosslinking monomer is crosslinked to the polymer skeleton, so it has excellent antifogging properties and sufficient hardness. and has strength, and functions sufficiently as a surface layer of a heat insulating sheet.

In addition, due to the combination of the water absorption and/or surfactant ability of the hydrophilic film provided on the surface layer and the insulation performance of the heat insulating film or sheet, even if the temperature difference between indoors and outdoors becomes large, fine particles remain on the indoor surface. Without water droplets (cloudy water) forming,
Sufficient transparency and clarity can be obtained.

[Brief explanation of the drawing]

FIGS. 1 to 4 are cross-sectional views showing examples of the anti-fog heat insulating sheet of the present invention having a low thermal conductivity layer, and FIG. It is a sectional view showing an example of a sheet. 4.14.24.34・ 5.15.25.35.42・ 41 ・Air layer/hydrophilic film/heat ray reflective film Applicant Dai Nippon Printing Co., Ltd. Agent Patent attorney Takaishi Tachibana Ma 1. 2.11
．． 12.31.32... Film Figure 1 Figure 3 Figure 5

Claims (7)

[Claims] (1) An antifogging heat insulating sheet, characterized in that a hydrophilic film crosslinked by electron beam irradiation is formed on the surface of the heat insulating film or sheet. (2) The antifogging heat insulating sheet according to claim 1, wherein the hydrophilic film is made of a polymer and a hydrophilic monomer, and is crosslinked by electron beam irradiation. (3) The antifogging heat insulating sheet according to claim 1, wherein the hydrophilic film is made of a polymer, a hydrophilic monomer, and a crosslinkable monomer, and is crosslinked by electron beam irradiation. Insulation sheet. (4) The antifogging heat insulating sheet according to claim 1, wherein the hydrophilic film is made of a polymer and a hydrophilic crosslinkable monomer, and is crosslinked by electron beam irradiation. sheet. (5) The antifogging heat insulating sheet according to any one of claims 1 to 4, wherein the hydrophilic film contains 100 parts by weight or less of a surfactant per 100 parts by weight of the polymer. Anti-fog insulation sheet. (6) The anti-fog heat insulating sheet according to any one of claims 1 to 5, wherein the heat insulating film or sheet has a low thermal conductivity layer. (7) The anti-fog heat insulating sheet according to any one of claims 1 to 5, wherein the heat insulating film or sheet reflects or blocks heat rays.