JP6251505B2 - Heat ray shielding film for windows - Google Patents

Description

  The present invention relates to a heat-shielding film for window pasting that has high transparency in the visible light region and has heat shielding properties for reflecting or absorbing light in the near-infrared region.

Sunlight is roughly classified into ultraviolet rays having a wavelength of 200 to 380 nm, visible rays having a wavelength of 380 to 780 nm, and infrared rays having a wavelength of 780 nm or more.
Among infrared rays, near infrared rays having a wavelength of 780 to 2100 nm are called so-called heat rays, and are converted into heat when irradiated on an object.

  In order to reduce the indoor temperature rise due to the near infrared rays contained in the sunlight, a film made of a material that reflects or absorbs near infrared rays such as metal oxides is formed on the window glass surface and used as a heat ray shielding glass. Has been done. As the film forming method, spray baking, CVD method, sputtering method, vacuum deposition method or the like has been selected (for example, Patent Document 1).

However, these film forming methods require a large-scale apparatus and vacuum equipment, have a problem in productivity and an increase in area, and have a drawback that the manufacturing cost of the film increases.
Further, when the metal oxide is exposed on the surface, visible light is reflected, so that there is a problem that the surface of the window glass becomes glossy and glaring, and the appearance is impaired.
Furthermore, when a film made of a material that reflects or absorbs near infrared rays is formed on the window glass itself, the near infrared rays are shielded even when it is not necessary to shield near infrared rays or when it is desirable to actively incorporate near infrared rays such as in winter. There was a problem of doing.

  As an alternative, there is a method in which a synthetic resin film containing a material that reflects or absorbs near infrared rays is attached to a window glass. For example, a material that reflects or absorbs near infrared rays, such as tungsten oxide, lanthanum hexaboride, antimony-containing tin oxide (ATO), tin-containing indium oxide (ITO), aluminum-containing zinc oxide (AZO), is added to the synthetic resin. It is made into a film (Patent Document 2, etc.). If such a synthetic resin film is attached to a window glass, it is inexpensive, and the problem of glaring the surface and impairing the beauty is eliminated. Moreover, when it is not necessary to shield near infrared rays or when it is desired to actively incorporate near infrared rays, it can be peeled off from the window glass.

  However, since a synthetic resin film used by being attached to a window glass is used in a severe environment that is constantly exposed to sunlight, there is a problem that the adhesive strength increases with time. If the adhesive force increases, the adhesive or adhesive of the synthetic resin film remains on the window glass surface at the time of peeling, and there is a problem that it takes time to remove the remaining glue.

JP 2000-169765 A JP 2007-231145 A

  The present invention is a heat-shielding film for window pasting which absorbs or reflects near infrared rays and suppresses temperature rise in the room, has high transparency, can be easily peeled off when heat-shielding performance is unnecessary, and at the time of peeling It is an object of the present invention to provide a heat-shielding film for window pasting having no adhesive residue.

  The inventors of the present invention have made various studies in order to solve the above-mentioned problems. By adding an amide-based lubricant to the adhesive layer of a synthetic resin film having a base material layer and an adhesive layer, the present inventors have found that The present invention was completed by finding that a heat-shielding film for window sticking that does not increase in adhesive strength even when used for a long period of time and does not have adhesive residue at the time of peeling can be obtained.

The present invention has been made under such knowledge, and the gist thereof is as follows.
(1) It comprises at least a base material layer and an adhesive layer, and the base material layer comprises at least a synthetic resin, a heat ray shielding agent, a hindered amine light stabilizer, and an ultraviolet absorber, It contains at least a synthetic resin, a hindered amine light stabilizer, a UV absorber, and an amide lubricant, and the amount of the amide lubricant added is 0.1 to 1 parts per 100 parts by weight of the synthetic resin constituting the adhesive layer. 5 parts by weight der is, the amount of adhesive hindered amine contained in the layer light stabilizers and ultraviolet absorbers, respectively 0.3 to 1.5 parts by weight of the synthetic resin 100 parts by weight which constitutes the pressure-sensitive layer heat ray shielding film for attaching window characterized by der Rukoto,
(2) The heat-shielding film for window sticking according to (1), wherein the amide-based lubricant is bisamide.
(3) The synthetic resin of the base material layer is a random polypropylene, The heat ray shielding film for window pasting as described in (1) or (2).

According to the present invention, the heat shielding effect can be obtained only by pasting the window-sealing heat-shielding film on the window glass, so that inexpensive and large-scale equipment and devices are not required.
Further, since a film made of a material that reflects or absorbs near-infrared rays is not formed on the window glass itself, the window glass is not glaring and the aesthetic appearance is not impaired.
Furthermore, when it is not necessary to shield near infrared rays or when it is desired to actively incorporate near infrared rays, it can be easily peeled off, and no glue remains.

Hereinafter, the present invention will be described in detail.
The heat ray shielding film for window pasting of the present invention comprises at least a base material layer and an adhesive layer, and the base material layer contains at least a synthetic resin, a heat ray shielding agent, a hindered amine light stabilizer, and an ultraviolet absorber. The adhesive layer comprises at least a synthetic resin, a hindered amine light stabilizer, an ultraviolet absorber, and an amide lubricant.
In the present specification, the “heat-shielding film for window pasting” may be simply referred to as “heat-shielding film” or “film”.

The base material layer of the heat ray shielding film of the present invention is made of a synthetic resin and has transparency and strength as a film. Synthetic resins include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), triacetyl cellulose (TAC), polycarbonate (PC), polyimide, polystyrene, polypropylene resin, polyethylene resin, cycloolefin resin, norbornene resin , Acrylic resins, polyvinyl chloride resins and the like.
Among these, random polypropylene is preferable because of its high transparency and excellent visibility.

  The base material layer contains at least a heat ray shielding agent, a hindered amine light stabilizer, and an ultraviolet absorber in the synthetic resin.

As the heat ray shielding agent, known materials are used. For example, as inorganic materials, tin-doped indium oxide fine particles, aluminum-doped zinc oxide fine particles, indium-doped zinc oxide fine particles, tin-doped zinc oxide fine particles, silicon-doped zinc oxide fine particles Lanthanum hexaboride fine particles, cerium hexaboride fine particles, tungsten oxide fine particles, metal fine particles, etc., and organic types include diimonium dyes, aminium dyes, phthalocyanine dyes, anthraquinone dyes, polymethine dyes, benzenethiol ammonium compounds, thiols Examples include urea derivatives and thiol metal complexes.
By adding such a heat ray shielding agent to the base material layer, a heat ray shielding effect can be imparted to the film.

  It is essential to add a hindered amine light stabilizer and an ultraviolet absorber to the base material layer. Since the heat ray shielding film of the present invention is used by being attached to a window glass, a high level of weather resistance is required. If a hindered amine light stabilizer and an ultraviolet absorber are not used, there is a problem that cracks occur in the heat ray shielding film during use, resulting in poor appearance, or difficulty in peeling due to deterioration of the resin when peeling from the window.

  The addition amount of the hindered amine light stabilizer is preferably 0.1 to 0.7 parts by weight with respect to 100 parts by weight of the synthetic resin constituting the substrate. If it is less than 0.1 part by weight, the effect of suppressing deterioration of the film over time may not be obtained. Moreover, when it exceeds 0.7 weight part, a hindered amine light stabilizer will become easy to bleed on the film surface, and there exists a possibility of impairing a film external appearance.

  Known materials are used as the ultraviolet absorber, and examples thereof include salicylic acid ester, benzotriazole, hydroxybenzophenone, and acrylonitrile substituted products. Such an ultraviolet absorber can be used individually by 1 type or in mixture of 2 or more types. Specifically, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-ethoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 5,5′-methylenebis (2-hydroxy 2-hydroxybenzophenones such as -4-methoxybenzophenone); 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butyl) Phenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-5′-tert-) Octylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′- 2- (2′-hydroxyphenyl) benzotriazoles such as cumylphenyl) benzotriazole, 2,2′-methylenebis (4-tert-octyl-6-benzotriazole) phenol; phenyl salicylate, resorcinol monobenzoate, 2, Benzoates such as 4-di-tert-butylphenyl-3 ′, 5′-di-tert-butyl-4′-hydroxybenzoate, hexadecyl-3,5-di-tert-butyl-4-hydroxybenzoate; Oxanilides such as ethoxy-4'-dodecyloxanilide; Cyanoacrylates such as ethyl-α-cyano-β, β-diphenylacrylate, methyl-2-cyano-3-methyl-3- (p-methoxyphenyl) acrylate Kind.

  It is preferable that the addition amount of a ultraviolet absorber is 0.1-0.7 weight part with respect to 100 weight part of synthetic resins which comprise a base material layer. If the amount is less than 0.1 parts by weight, sufficient ultraviolet absorption performance may not be exhibited during use. Moreover, when it exceeds 0.7 weight part, there exists a possibility that a ultraviolet absorber may bleed on the film surface and a film external appearance may be impaired.

  The thickness of the base material layer is preferably about 40 to 300 μm. If the thickness is less than 40 μm, the strength may be insufficient. On the other hand, if the thickness exceeds 300 μm, the weight increases, resulting in inconvenience in handling and high cost.

The pressure-sensitive adhesive layer of the heat ray shielding film of the present invention has adhesiveness to the window glass.
Examples of the synthetic resin constituting the adhesive layer include styrene elastomers, acrylic elastomers, olefin elastomers, and ethylene-vinyl acetate copolymers.
Among these, a styrene elastomer is suitable because it is excellent in compatibility with a random polypropylene that is preferable as a synthetic resin constituting the base material layer.
Styrenic elastomers include SIS (styrene / isoprene / styrene block copolymer), SBS (styrene / butadiene / styrene block copolymer), SEPS (styrene / ethylene / propylene / styrene block copolymer), SEBS (styrene).・ Ethylene / butylene / styrene block copolymer) and SBBS (styrene / butadiene / butylene / styrene block copolymer) can be used. From the viewpoint of compatibility with random polypropylene and weather resistance, SEBS ( Styrene / ethylene / butadiene / styrene block copolymer) is preferred.
Moreover, it is preferable that the styrene content of a styrene-type elastomer is 10 to 30 weight%. If it is less than 10% by weight, the initial adhesive force when pasted on the window glass is too large, and the peelability may be impaired. On the other hand, if it exceeds 30% by weight, the initial adhesive strength becomes too small, which may make it difficult to adhere to the window glass.

  Since the heat ray shielding film of the present invention is used by being attached to a window glass, a high level of weather resistance is required. Therefore, the addition of a hindered amine light stabilizer and an ultraviolet absorber is essential in the adhesive layer as well as the base material layer.

  The addition amount of the hindered amine light stabilizer in the adhesive layer is preferably 0.3 to 1.5 parts by weight with respect to 100 parts by weight of the synthetic resin constituting the adhesive layer. If the amount is less than 0.3 parts by weight, the effect of suppressing deterioration of the adhesive layer over time may not be obtained. If the amount exceeds 1.5 parts by weight, the film surface may bleed or adhesion may increase. There is a bug to do.

  The ultraviolet absorber used in the adhesive layer is the same as the ultraviolet absorber used in the above-mentioned base material layer, and the amount added is 0.1% by weight with respect to 100 parts by weight of the synthetic resin constituting the adhesive layer. It is preferable that it is 3-1.5 weight part. If the amount is less than 0.3 part by weight, there is a possibility that sufficient ultraviolet absorption performance is not exhibited at the time of use, and if it exceeds 1.5 part by weight, there is a problem that the film surface is bleed or adhesive force is increased.

The heat ray shielding film of the present invention contains an amide lubricant in the adhesive layer. By adding an amide-based lubricant, an increase in adhesive force (so-called progress) due to a change with time of the heat ray shielding film can be suppressed.
Examples of amide-based lubricants include monoamides such as stearic acid amide, lauric acid amide, oleic acid amide, and erucic acid amide, methylene bis stearic acid amide, ethylene bis stearic acid amide, ethylene bis lauric acid amide, ethylene bis oleic acid amide, ethylene Bisamides such as biserucic acid amide may be mentioned, and bisamide is preferred in the present invention.
Bisamide has advantages such as excellent pastability to glass and heat resistance at the initial stage and a very high effect of suppressing the progress of adhesive strength over time.

  The amount of the amide-based lubricant added is 0.1 to 1.5 parts by weight with respect to 100 parts by weight of the synthetic resin constituting the adhesive layer. If the amount is less than 0.1 part by weight, the adhesive layer will be increased in adhesiveness due to a change with time of the heat ray shielding film, and the releasability from the glass becomes poor. On the other hand, if it exceeds 1.5 parts by weight, the initial stickability of the heat ray shielding film to the glass becomes poor.

  The thickness of the adhesive layer is preferably 5 to 70 μm. If it is less than 5 μm, the adhesive strength may be insufficient. On the other hand, if it exceeds 70 μm, not only will the weight increase and cost increase, but it may be difficult to adjust the initial adhesive force and to suppress the progress over time.

  Additives such as an antioxidant, a plasticizer, an antistatic agent, a flame retardant, an inorganic filler, and a pigment may be added to the base material layer and the adhesive layer as long as the effects of the present invention are not impaired.

  Although the heat ray shielding film of this invention has a base material layer and an adhesion layer at least, it is also possible to provide functional layers, such as a surface protective layer and a design layer, on a base material layer according to the objective.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited by these Examples.

<Examples 1-5, Comparative Examples 1-3>
T-die extrusion molding was carried out with the formulation shown in Table 1 to produce a film having a thickness of 100 μm (base layer 80 μm, adhesive layer 20 μm). The unit of numerical values in the table is “parts by weight”.

In the table;
・ Polypropylene resin 1
Random polypropylene WINTEC WFX4 made by Nippon Polypropylene
・ Polypropylene resin 2
Homopolypropylene Nobrene FLX80E4 manufactured by Sumitomo Chemical Co., Ltd.
・ Heat ray shielding agent 1
Aluminum powder HCM No. manufactured by Dainichi Seika Kogyo Co., Ltd. 7 Silver heat ray shielding agent 2
Tungsten oxide YMDS-165 manufactured by Sumitomo Metal Mining Co., Ltd.
・ Hindered amine light stabilizer ADEKA LA-63P
UV absorber Kemipro Kasei Co., Ltd. KEMISORB 73
Styrene elastomer Styrene-ethylene-butadiene-styrene copolymer (styrene content: 20% by weight) Tuftec H1052 manufactured by Asahi Kasei Chemicals
・ Lubricant 1
Bisamide Nippon Kasei Co., Ltd. Bisamide LA
・ Lubricant 2
Monoamide Amide AP-1 manufactured by Nippon Kasei Co., Ltd.
・ Lubricant 3
Acrylic polymer lubricant Mitsubishi Rayon Co., Ltd. METABLEN L-1000

  The following evaluation was performed about the film obtained by the said Example and comparative example.

<Weather resistance>
The films obtained in each Example and Comparative Example were attached to a glass plate having a thickness of 3 mm, put into a sunshine weather, the appearance of the film after 1000 hours was confirmed, and evaluated according to the following criteria.
○ ・ ・ ・ No appearance defects such as cracks in the film × ・ ・ ・ Changes in appearance such as cracks are seen in the film

<Bleed-out>
The films obtained in each Example and Comparative Example were attached to a glass plate having a thickness of 3 mm, put into a sunshine weather, the appearance of the film after 1000 hours was confirmed, and evaluated according to the following criteria.
◯ ... Cloudiness is not confirmed on the film surface × ... Cloudiness is confirmed on the film surface

<Initial pasteability>
The test was performed using a glass plate having a thickness of 3 mm, a width of 30 mm, and a length of 200 mm as a test plate. The test plate was used after sufficiently wiping with a dry cloth in order to remove dirt on the surface. The test piece used was 25 mm wide and 200 mm long. For attaching the test piece to the test plate, a manual press roll is used, and the press roller has a surface coated with a rubber layer having a spring hardness of 80 ± 5 Hs and a thickness of about 6 mm as defined in JIS K 6301. The one with a diameter of 83 mm and a mass of 2000 ± 50 g was used. After leaving the test piece affixed to the test plate for 30 minutes, the peel force (180 degree peel) when peeled from the test piece in the horizontal direction at a speed of 300 mm / min was measured 6 times, and the average value was determined as the adhesive strength. did. The evaluation criteria are as follows.
○ ... Adhesive strength is 0.02-0.20N / 25mm
× ・ ・ ・ Cannot be attached to the test plate

<Peelability>
The test was performed using a glass plate having a thickness of 3 mm, a width of 30 mm, and a length of 200 mm as a test plate. The test plate was used after sufficiently wiping with a dry cloth in order to remove dirt on the surface. The test piece used was 25 mm wide and 200 mm long. For attaching the test piece to the test plate, a manual press roll is used, and the press roller has a surface coated with a rubber layer having a spring hardness of 80 ± 5 Hs and a thickness of about 6 mm as defined in JIS K 6301. The one with a diameter of 83 mm and a mass of 2000 ± 50 g was used. The test piece affixed to the test plate was placed in an oven at 60 ° C. and allowed to stand for one week. After one week, after taking out from the oven and allowing to stand at room temperature for one hour, the peeling force (peeling 180 degrees) when the test piece was peeled off at a speed of 300 mm / min in the horizontal direction was measured 6 times, and the average value was obtained. Was the adhesive strength. The evaluation criteria are as follows.
Note that Comparative Example 2 could not be evaluated because it could not be attached to the test plate.
○: Adhesive strength is less than 1.0 N / 25 mm Δ: Adhesive strength is 1.0 N / 25 mm or more and less than 2.0 N / 25 mm × ... Adhesive strength is 2.0 N / 25 mm or more

<Transparency>
In accordance with JIS K 7105, measurement was performed using a haze meter, and evaluation was performed according to the following criteria.
○ ・ ・ ・ less than 20% △ ・ ・ ・ 20% or more and less than 50% × ・ ・ ・ 50% or more

  From the result of Examples 1-5, it turns out that the heat ray shielding film of this invention is excellent in the sticking property to glass, and peelability. Therefore, it is suitably used as a heat ray shielding film for window pasting.

Claims (3)

Having at least a base material layer and an adhesive layer,
The substrate layer comprises at least a synthetic resin, a heat ray shielding agent, a hindered amine light stabilizer, and an ultraviolet absorber.
The adhesive layer contains at least a synthetic resin, a hindered amine light stabilizer, an ultraviolet absorber, an amide lubricant,
The amount of the amide-based lubricant Ri 0.1 to 1.5 parts by weight der the synthetic resin 100 parts constituting the adhesive layer,
The addition amount of the hindered amine light stabilizer and ultraviolet absorber contained in the adhesive layer, and wherein 0.3 to 1.5 parts by weight der Rukoto respectively synthetic resin 100 weight parts that constitute the adhesive layer A heat-shielding film for pasting windows.   The heat-shielding film for window sticking according to claim 1, wherein the amide lubricant is bisamide.   The heat ray shielding film for window sticking according to claim 1 or 2, wherein the synthetic resin of the base material layer is random polypropylene.