JP2014141015A - Laminate film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate film having a hard coat layer which has high durability and excellent infrared reflection performance, transparency and scratch resistance and is suitable for pasting on a window.SOLUTION: There is provided a laminate film formed by laminating a heat ray reflecting layer and a hard coat layer in this order on one surface of a substrate composed of a synthetic resin, where the heat ray reflecting layer has a multi-layer structure in which a metal thin film and a metal oxide thin film are alternately laminated (when the number of the layers of the metal thin film is defined as "n", the number of the layers of the metal oxide thin film is "n+1"), the metal oxide thin film in contact with at least the hard coat layer contains tin as the main component of the metal component and contains 3 to 20 mass% of niobium of the metals.

Description

  The present invention relates to a laminated film in which a heat ray reflective layer and a protective layer are formed on a base material made of a synthetic resin, and is excellent in infrared reflectivity, transparency, scratch resistance, and high durability even when used for a long time. The present invention relates to a laminated film. Further, the present invention relates to a laminated film suitable for window pasting that can suppress the inflow of solar heat from the outside and can also suppress the outflow of indoor heating heat when pasted on a window glass of a house or a building. .

  Conventionally, a laminated film in which a heat ray reflective layer in which metal thin films / metal oxide thin films are alternately laminated on a glass of an opening of a house or building, for example, a window, and a protective layer are sequentially formed. These laminated films can suppress the inflow of solar heat (near infrared) from the outside to the room and the outflow of heating heat (far infrared gland) from the room to the outside by the infrared reflective function of the metal thin film. , Energy saving effect can be obtained throughout the year. Furthermore, the transparency is improved by laminating a metal oxide thin film having a high refractive index to ensure appearance visibility, and the scratch resistance is exhibited by laminating a protective layer.

  As the above-mentioned laminated film, for example, a transparent laminated film in which metal oxide thin films and metal thin films are alternately laminated on at least one surface of a transparent polymer film and a protective layer is further formed thereon has been proposed ( Patent Document 1). Patent Document 1 exemplifies titanium oxide, zinc oxide, indium oxide, niobium oxide, and the like as the metal oxide thin film, and among these, titanium oxide having the highest refractive index is preferably used. Since titanium oxide has a high refractive index, it is excellent in terms of improving transparency and ensuring appearance visibility, but is a metal oxide that exhibits a photocatalytic reaction. When titanium oxide absorbs the energy of sunlight, electrons in the valence band are photoexcited to generate conduction electrons and holes. At this time, it has the characteristic of oxidizing and decomposing various organic substances by the reducing power of electrons generated in the conductor and / or the oxidizing power of holes generated in the valence band.

  Due to the characteristics of titanium oxide described above, when a laminated film in which a protective layer is formed on the titanium oxide with an organic substance such as an acrylic resin is used for window pasting, the acrylic resin is oxidized and decomposed by the photocatalytic reaction of the titanium oxide, and the titanium oxide and There arises a problem that the adhesiveness at the interface with the acrylic resin is lowered or a crack occurs in the protective layer made of the acrylic resin, resulting in poor durability.

  On the other hand, when the protective layer is formed of an inorganic substance such as silicon oxide as proposed in the present method, the protective layer is not decomposed by a photocatalytic reaction such as titanium oxide, but a sufficient protective effect cannot be obtained. A problem arises that the thin film is corroded and the infrared reflection performance is lowered, and the scratch resistance is poor.

JP 2012-135888 A

  In view of the background of such prior art, the present invention is a laminated film in which metal thin films / metal oxide thin films are alternately laminated, and a hard coat layer made of an organic material is formed as a protective layer on the metal oxide thin film. It is intended to provide a laminated film suitable for window pasting applications that has high durability and is excellent in infrared reflection performance, transparency, and scratch resistance.

The present invention employs the following means in order to solve such problems.
(1) A laminated film in which a heat ray reflective layer and a hard coat layer are laminated in order on one side of a base material made of synthetic resin, the heat ray reflective layer has a multilayer structure in which metal thin films and metal oxide thin films are alternately laminated ( When the number of layers of the metal thin film is “n”, the number of layers of the metal oxide thin film is “n + 1”), and at least the metal oxide thin film in contact with the hard coat layer has tin as the main component of the metal component. A laminated film comprising 3 to 20% by mass in a metal,
(2) The laminated film, wherein a barrier layer is formed between the metal thin film and the metal oxide thin film which are heat ray reflective layers,
(3) The barrier layer formed between the metal thin film and the metal oxide thin film is a metal oxide containing at least one of tin and niobium, and has a lower oxygen content than the metal oxide thin film. The laminated film,
(4) The hard coat layer includes a crosslinked resin having one or more polar groups selected from the group consisting of a phosphate group, a sulfonic acid group, and an amide group, and has a thickness of 0.5 to 2.0 μm. Any one of the above-mentioned laminated films,
(5) A window pasting film in which an adhesive layer is formed on the side opposite to the heat ray reflective layer / hard coat layer forming surface of the laminated film according to any one of the above, and the wavelength measured from the surface of the hard coat layer. A film for window pasting, wherein a far infrared reflectance of 5 to 50 μm is 85% or more and a solar heat penetration rate is 0.6 or less.

  ADVANTAGE OF THE INVENTION According to this invention, the laminated film suitable for the window sticking use which has high durability while having a hard-coat layer, and was excellent in infrared reflective performance, transparency, and damage resistance is obtained.

The laminated film of the present invention is a laminated film in which a heat ray reflective layer and a hard coat layer are laminated in order on one side of a base material made of a synthetic resin, and the heat ray reflective layer alternately laminates metal thin films and metal oxide thin films. It has a multilayer structure (when the number of metal thin film layers is “n”, the number of metal oxide thin film layers is “n + 1”), and at least the metal oxide thin film in contact with the hard coat layer contains tin as a metal component. Of these, the main component is 3 to 20% by mass of niobium.
The substrate used in the present invention is not particularly limited as long as it is excellent in transparency and weather resistance, but for example, polyethylene terephthalate, polycarbonate, acrylic, nylon and the like are preferable, and are necessary when forming a metal film. In view of heat resistance, cost, and the like, polyethylene terephthalate is more preferable. Any substrate may be provided with an easy-adhesion layer or subjected to a surface treatment such as corona treatment, plasma treatment or saponification. Forming a metal oxide thin film on a substrate subjected to these treatments is preferable because adhesion between layers is improved. Although there is no restriction | limiting in particular about the thickness of this base material, When considering the handleability at the time of using mechanical strength, heat resistance, and a window sticking application, it is preferable that it is a film which is 10-150 micrometers. If the thickness is thin, wrinkles due to thermal shrinkage tend to occur in the surface treatment process or the metal layer or metal oxide layer forming process. On the other hand, if the thickness is too thick, not only will the material cost increase, but the workability during construction on windows tends to be inferior. On the other hand, when the window is prevented from being damaged and security performance is imparted, it is also useful to be thick.

  Next, the heat ray reflective layer has a multilayer structure in which metal thin films and metal oxide thin films are alternately laminated. When the number of metal thin films is “n”, the number of metal oxide thin films is “n + 1”. expressed. Specifically, when the number of metal thin films “n” is one, the number of metal oxide thin films “n + 1” is two, which are laminated in the order of metal oxide thin film / metal thin film / metal oxide thin film. It has a three-layer structure. Further, when the number of metal thin films “n” is two, the number of metal oxide thin films “n + 1” is three, and metal oxide thin film / metal thin film / metal oxide thin film / metal thin film / metal oxide thin film. It becomes the 5 layer constitution laminated in order. Even when the number of metal thin films “n” is three or more, the number of metal oxide thin films and the total number of stacked layers can be similarly calculated. As the total number of laminated layers increases, infrared reflection performance and visible light transmission performance (transparency) are improved. However, even if a large number of layers are laminated, the effect is not greatly improved.

  Next, the metal oxide thin film in contact with at least the hard coat layer contains tin as a main component among the metal components and contains 3 to 20% by mass of niobium. A metal oxide having a high refractive index is preferably used for the metal oxide thin film from the viewpoint of improving transparency and ensuring appearance visibility. Titanium oxide (refractive index: about 2.6 (wavelength: 500 nm)) and niobium oxide (refractive index: about 2.3 (wavelength: 500 nm)) have been known as these substances. Absorbs and shows a strong photocatalytic reaction. On the other hand, tin oxide (refractive index 1.9: wavelength 500 nm) is not as high in refractive index as titanium oxide and niobium oxide, but has a large band gap. It is an oxide not shown.

  From the viewpoint described above, the metal oxide thin film in contact with the hard coat layer contains tin as a main component of the metal component, and preferably contains 50% by mass or more of the metal component and contains 3 to 20% by mass of niobium. By doing so, it is possible to obtain a metal oxide thin film having a high refractive index without showing a strong photocatalytic reaction. If the niobium content is low, the refractive index does not change significantly, and if it is too high, a photocatalytic reaction may be exhibited. The refractive index is preferably 2.0 or more (wavelength 500 nm) from the viewpoint of reducing visible light reflection and improving transparency.

  Further, metal oxides other than tin and niobium (for example, oxides of aluminum, zirconium, zinc, etc.) may be contained.

  The thickness of each layer of the metal oxide thin film is 10 nm or more, preferably 30 nm or more, on the other hand, 100 nm or less, preferably 60 nm or less. Furthermore, metal oxides having the above-described composition may be used for other metal oxide thin films not in contact with the hard coat layer, but metal oxides such as titanium oxide, niobium oxide, zinc oxide, tin oxide, Alternatively, it can be used as a composite oxide of these metals or a mixture of the above oxides.

  The metal thin film used in the present invention is preferably composed mainly of silver having excellent infrared reflection performance. The amount of silver is preferably 90% by mass or more. Furthermore, it is also preferable to use an alloy to which one or more of gold, palladium, copper, bismuth, nickel, niobium, magnesium, zinc, aluminum and the like are added for the purpose of improving the corrosion resistance of silver. Among these metals, it is particularly preferable to contain gold and / or palladium from the viewpoint of achieving both infrared reflection performance and corrosion resistance. Moreover, although there is no restriction | limiting in particular in content of gold | metal | money and / or palladium, From a viewpoint of corrosion resistance and cost, it is preferable that the total amount of a gold atom and a palladium atom contains 2-5 mass% in a metal thin film. If it is less, the effect of suppressing silver corrosion cannot be obtained. On the other hand, if the amount is too large, an improvement effect commensurate with the cost increase cannot be obtained only by an increase in cost. Although there is no restriction | limiting in particular about the thickness of each layer of a metal thin film, It is preferable to select suitably in the range of 5-25 nm in view of the required infrared reflective performance and visible light transmission performance. When the thickness is small, the transparency is excellent, but the infrared reflection performance tends to be lowered. On the other hand, if it is too thick, the transparency is lowered, the amount of metal used is increased, and this is not preferable economically.

  These metal thin films and metal oxide thin films can be formed by a known technique such as vacuum deposition, sputtering, or ion plating. In addition, the metal composition of the metal thin film and the metal oxide thin film can be quantified using a known analysis method such as ICP emission analysis, XPS, or XRF.

  In the laminated film of the present invention, a barrier layer is preferably formed between the metal thin film and the metal oxide thin film that are heat ray reflective layers. The barrier layer is made of metal or a metal suboxide obtained by partially oxidizing the metal, and has a function of protecting the metal thin film from oxygen, heat, moisture, etc. when forming the metal oxide thin film on the metal thin film. By forming the barrier layer, corrosion of the metal thin film can be prevented, which can contribute to improvement of infrared reflectance. Furthermore, the metal composition of the barrier layer is a metal oxide containing at least one of tin and niobium, and the oxygen content is lower than that of the metal oxide thin film, preventing corrosion of the metal thin film, and It is preferable at the point which improves adhesiveness with a metal oxide thin film. Here, the oxygen content of the metal oxide thin film refers to “the oxygen content of the metal oxide thin film” divided by “the amount of oxygen in a state where the metal constituting the metal oxide thin film is completely oxidized”. Similarly, the oxygen content of the barrier layer is obtained by dividing “the oxygen content of the barrier layer” by “the oxygen amount in a state where the metal constituting the barrier layer is completely oxidized”. Therefore, when the oxygen content of the metal oxide is X% and the oxygen content of the barrier layer is Y%, the relationship X> Y is established.

  In order to form a barrier layer having a lower oxygen content as compared with a metal oxide thin film, it may be formed by reducing the amount of oxygen input during film formation. For example, when a metal oxide thin film is formed with an oxygen input amount of 10%, the barrier layer may be formed with an oxygen input amount of less than 10%.

  Next, the hard coat layer used in the laminated film of the present invention has a function of protecting the metal thin film / metal oxide thin film. Preferred are organic compounds and organosilicon compounds. Preferred are these polymers and polymers having a crosslinked structure.

  The thickness is preferably 0.5 to 2.0 μm. The resin constituting the hard coat layer can be obtained by crosslinking by irradiating with ultraviolet rays, electron beams or the like. In that case, a highly transparent and durable material is preferable. For example, an acrylic resin, a urethane resin, a fluorine resin, or a silicon resin can be used alone or in combination. The resin preferably contains one or more polar groups selected from the group consisting of phosphoric acid groups, sulfonic acid groups and amide groups. Examples thereof include a method of copolymerizing an acrylic acid derivative or a methacrylic acid derivative having a polar group such as phosphoric acid, amide, and sulfonic acid. As the acrylic acid derivative and methacrylic acid derivative described above, those having a phosphoric acid group are preferable, and for example, hydrogen phosphate = bis [2- (methacryloyloxy) ethyl] can be used. By including a crosslinked resin having a polar group in the hard coat layer, it becomes possible to improve the adhesion to the metal oxide thin film that is the base of the hard coat layer, and to improve durability and scratch resistance. .

  Further, the hard coat layer may have a single layer structure, but may be formed of two or more different layers. For example, a two-layer structure composed of a cross-linked resin single layer and a cross-linked resin containing a polar group may be used. However, in this case, it is preferable to form a layer containing a polar group in the layer in contact with the metal oxide thin film in terms of improving adhesion.

  The thickness of the hard coat layer is 0.5 μm or more, preferably 0.8 μm or more, on the other hand, 2.0 μm or less, preferably 1.5 μm or less. If the hard coat layer is thin, sufficient scratch resistance cannot be obtained. If the hard coat layer is thick, the infrared absorption amount of the hard coat layer increases and the infrared reflection performance tends to decrease.

  In addition, the hard coat layer can be crosslinked by applying a resin solution by a gravure coating method, reverse roll coating method, roll coating method, dip coating method, or the like, and then irradiating it with ultraviolet rays, electron beams or the like. .

  Next, an undercoat layer may be formed between the substrate and the heat ray reflective layer. Forming the undercoat layer is preferable because adhesion between layers can be improved and corrosion of the metal thin film can be suppressed. As the material for forming the undercoat layer, a resin is preferable, and a material having high transparency and durability is preferable. For example, acrylic resins, urethane resins, fluorine resins, silicone resins and the like can be used alone or as a mixture. These undercoat layers are coated with a resin-containing solution by a known technique such as a gravure coating method, reverse roll coating method, roll coating method, dip coating method, etc., dried, and then, if necessary, ultraviolet rays, electron beams, etc. Can be formed by irradiating and curing. The thickness of the undercoat layer is 0.5 μm or more, preferably 1.0 μm or more, on the other hand, 5 μm or less, preferably 3 μm or less. If the thickness of the undercoat layer is thin, it is difficult to uniformly coat the surface of the substrate, and the effect of improving the scratch resistance tends to be insufficient. On the contrary, even if it is formed too thick, there is a tendency that no further improvement in scratch resistance is observed.

  The laminated film of the present invention can be easily pasted into a window if an adhesive layer is formed on the surface opposite to the surface on which the heat ray reflective layer and the hard coat layer are formed. In that case, it is preferable that the far-infrared reflectance of wavelength 5.5-50 micrometers measured from the surface of the hard-coat layer of a laminated | multilayer film is 85% or more, and the solar radiation heat penetration rate is 0.6 or less. The hard coat layer is a layer located on the outermost surface on the indoor side when used for a window pasting application, and the far-infrared reflectance measured from the layer side indicates the reflectance of heating heat. When the far-infrared reflectivity satisfies 85% or more, it becomes possible to satisfy the heat transmissivity of 4.0 W / m 2 · K specified by the energy-saving index “next-generation energy-saving standards” for houses.

  Moreover, since the solar heat penetration rate satisfies 0.6 or less, it is possible to suppress the penetration of solar radiation from the outside into the room. By satisfying the above-mentioned values for the heat transmissibility and the solar heat penetration rate, energy-saving performance can be exhibited throughout the year regardless of summer or winter, and a laminated film suitable for window pasting applications can be obtained.

  Hereinafter, the present invention will be described more specifically with reference to examples. The production method of the test specimen for evaluation used for the measurement of the characteristic values shown in the examples and the measurement / calculation method of the characteristic values are as follows.

A. Preparation of test specimen for evaluation (1) The laminated film is cut into a 50 mm square.
(2) An adhesive layer is formed on the surface opposite to the surface on which the hard coat layer of the film cut in the above (1) is formed.
(3) Next, it is bonded to a 3 mm thick float glass through the adhesive layer formed in the item (2).

B. Durability (1) Standard: Conforms to JIS A5759-2008.
(2) Measuring method:
i) Using a sunshine weather meter (manufactured by Suga Test Instruments Co., Ltd.), irradiate ultraviolet rays from the glass surface side of the specimen. The irradiation conditions are as shown in Table 10 of JIS A5759 (black panel temperature 63 ° C., relative humidity 50%, radiation intensity 255 W / m 2, watering for 18 minutes during 120 minutes irradiation), and the irradiation time is 1000 hours.
(3) Criteria:
“◯”: no hard coat layer peeling and cracks, “×”: hard coat layer peeling or cracks.

C. Far-infrared reflectance (1) Standard: Conforms to JIS R3106-1998 (2) Measurement method:
i) Using a spectrophotometer “IR Prestige-21 (manufactured by Shimadzu Corporation)” and a specular reflection measurement unit “SRM-8000A (manufactured by Shimadzu Corporation)”, a spectral reflection of a test specimen for evaluation having a wavelength of 5 to 25 μm. Measure the rate. An Al vapor deposition mirror is used for the standard plate.
ii) Extract the spectral reflectance at the selected wavelengths of the numbers λ1 (wavelength 5.5 μm) to λ30 (wavelength 50 μm) described in Appendix 3 of the JIS text from the spectral reflectance. In addition, the value of (lambda) 24 (wavelength 23.3 micrometers) is used for the reflectance of (lambda) 25 (wavelength 25.2 micrometers)-(lambda) 30 (wavelength 50 micrometers).
iii) Multiply the extracted spectral reflectance by the standard reflectance of the Al vapor deposition mirror described in Appendix 3 of the JIS text to obtain the reflectance of the evaluation specimen at the selected wavelength of λ1 to λ30.
iV) The average value of the reflectance is defined as the far-infrared reflectance.
(3) Measurement conditions: Wavelength range “5 to 25 μm”, avodis coefficient “Happ-Genzel”, integration count “20 times”, resolution “4.0 cm −1”.

D. Solar heat penetration rate (1) Standard: Conforms to JIS A5759-2008 (2) Measurement method:
i) Using a spectrophotometer "UV-3150 (manufactured by Shimadzu Corporation)", the spectral transmittance and spectral reflectance of the test specimen for evaluation at a wavelength of 300 to 2500 nm are measured at intervals of 5 nm.
ii) The solar transmittance is calculated by multiplying the spectral transmittance measured in item i) by the weighting factor described in Table 13 of the JIS text and performing a weighted average. The solar reflectance is calculated by multiplying the spectral reflectance measured in the item i by the standard reflectance of the Al deposition mirror and performing a weighted average.
iii) The solar heat penetration rate is calculated from the solar radiation transmittance and solar reflectance.

E. Visible light transmittance (1) Standard: Conforms to JIS R3106-1998 (2) Measurement method:
i) Using a spectrophotometer “UV-3150 (manufactured by Shimadzu Corporation)”, the spectral transmittance of the test specimen for evaluation at wavelengths of 400 to 780 nm is measured at intervals of 10 nm. ii) After multiplying the transmittance by the weight coefficient described in Appendix 1 of the JIS text, an average value was calculated to obtain the visible light transmittance (%).
(3) Measurement conditions: wavelength range “400 to 780 nm”, scan speed “high speed”,
Decomposition capacity “10 nm”.

F. Scratch resistance (1) Measuring method:
i) Abrasion with steel wool using a Gakushin abrasion tester “RT-200 (manufactured by Daiei Kagaku Seisakusho Co., Ltd.)”.
ii) Measurement conditions: rubbing speed 10, rubbing frequency 100 reciprocations, load 500 g, friction element 30 mm × 10 mm, steel wool “Bonster (registered trademark: manufactured by Nippon Steel Wool Co., Ltd.) # 0000”.
(2) Criteria:
“◎”: No visual scratch of 2 mm width or more, visual scratch of 0-5 pieces / 10 mm width, “◯”: No visual scratch of 2 mm width or more, visual scratches of 6-10 pieces / 10 mm width, “×”: There are visual scratches of 2 mm width or more, or 11 or more visual scratches / 10 mm width.

[Example 1] An acrylic hard coating agent "" OPSTAR "(registered trademark, the same applies hereinafter) Z7535 (manufactured by JSR Corporation)" was applied to one side of a PET film having a thickness of 50 [mu] m, dried, and then irradiated with UV. An undercoat layer having a thickness of 3 μm was formed and used as a base material for a laminated film. Next, a first 40 nm thick first sputtering target material (refractive index: 2.1, wavelength 500 nm) having a metal composition of tin: niobium = 97 mass%: 3 mass% is formed on the undercoat layer of the substrate. A metal oxide thin film as a layer was formed (sputtering gas was argon: oxygen = 90%: 10% (pressure ratio)). Subsequently, a metal thin film having a thickness of 20 nm was formed on the first metal oxide thin film using a sputtering target material containing 3% by mass of gold in silver (sputtering gas is argon = 100%). Further, using the same sputtering target material as the first layer metal oxide thin film, a second metal oxide thin film having a thickness of 40 nm was formed under the same conditions, and the first metal oxide thin film / metal thin film / A heat ray reflective layer composed of three layers of the second metal oxide thin film was formed.
Next, an acrylic resin ““ OPSTAR ”Z7535 (manufactured by JSR Corporation)” is applied on the heat ray reflective layer, dried and then irradiated with UV to form a hard coat layer having a thickness of about 1.0 μm, and a laminated film Got.

  [Example 2] A laminated film was obtained in the same manner as in Example 1 except that the metal composition of the sputtering target material for the metal oxide thin film was changed to tin: niobium = 95% by mass: 5% by mass.

  Example 3 A laminated film was obtained in the same manner as in Example 1 except that the metal composition of the sputtering target material for the metal oxide thin film was changed to tin: niobium = 90% by mass: 10% by mass.

  Example 4 A laminated film was obtained in the same manner as in Example 1 except that the metal composition of the sputtering target material for the metal oxide thin film was changed to tin: niobium = 85% by mass: 15% by mass.

  Example 5 A film having an undercoat layer formed by the same method as in Example 1 was used as a base material, and a heat ray reflective layer was formed on the base material by the same method as in Example 2.

  Next, a methacrylic acid derivative “light ester P-2M (manufactured by Kyoeisha Chemical Co., Ltd.)” containing a phosphate group is solidified on an acrylic resin “OPSTAR Z7535 (manufactured by JSR Corporation)” on the heat ray reflective layer A coating solution mixed so as to be 2% by mass in the minute was applied, dried and then irradiated with UV to form a hard coat layer having a thickness of about 1.0 μm to obtain a laminated film.

  [Example 6] A barrier layer having a thickness of 5 nm was formed between the metal thin film and the second metal oxide thin film to form a first metal oxide thin film / metal thin film / barrier layer / second metal oxide thin film. A laminated film was obtained in the same manner as in Example 5 except for. The barrier layer uses a sputtering target material having a metal composition of tin: niobium = 95% by mass: 5% by mass, and the oxygen content is compared with a metal oxide thin film obtained by forming a sputtering gas with 100% argon. Is a low metal suboxide thin film.

  [Example 7] A laminated film was obtained in the same manner as in Example 6 except that the thickness of the barrier layer was changed to 8 nm.

  [Example 8] A laminated film was obtained in the same manner as in Example 5 except that the thickness of the hard coat layer was changed to 0.8 µm.

  [Example 9] A laminated film was obtained in the same manner as in Example 5 except that the thickness of the hard coat layer was changed to 1.2 µm.

  [Example 10] A laminated film was obtained in the same manner as in Example 5 except that the thickness of the hard coat layer was changed to 1.5 µm.

  Comparative Example 1 A laminated film was obtained in the same manner as in Example 1, except that the metal composition of the sputtering target material for the metal oxide thin film was changed to niobium = 100% by mass.

  Comparative Example 2 A laminated film was obtained in the same manner as in Example 1, except that the metal composition of the sputtering target material for the metal oxide thin film was changed to tin: niobium = 50 mass%: 50 mass%.

Comparative Example 3 A laminated film was obtained in the same manner as in Example 1 except that the metal composition of the sputtering target material for the metal oxide thin film was changed to tin: niobium = 70 mass%: 30 mass%.
About each test body of Examples 1-10 and Comparative Examples 1-3, durability, adhesion, scratch resistance, far-infrared gland reflectivity, solar heat penetration rate, visible light transmittance were measured using the measurement methods described above. The results of measuring are shown in Tables 1 and 2.
Examples 1-4 in which the metal composition of the metal oxide thin film was tin: niobium = 97% by mass: 3% by mass, 95% by mass: 5% by mass, 90% by mass: 10% by mass, and 85% by mass: 15% by mass. In any of the above tests, the hard coat layer was not peeled off or cracked in the durability test (SWOM 1000 hours), and the determination was “◯”. Furthermore, in all specimens, the far-infrared gland reflectivity is 85% or more, the solar heat penetration rate is 0.6 or less, and the visible light transmittance, which is an index of transparency, is 70% or more. Visibility was also good. Further, the determination of scratch resistance was “◯”.
Next, in Example 5 in which the metal composition of the metal oxide thin film was tin: niobium = 95% by mass: 5% by mass and the hard coat layer contained a phosphate group, the scratch resistance was higher than that in Example 2. It was improved and the judgment was “◎”.
Further, in Examples 6 and 7 having the same configuration as that of Example 5 and having a barrier layer, corrosion of the metal thin film could be suppressed and the far infrared gland reflectivity was improved to 90% or more.
Moreover, also about Examples 8-10 which changed the film thickness of the hard-coat layer, peeling of a hard-coat layer and a crack did not generate | occur | produce by durability evaluation, but the determination was "(circle)". Moreover, it was confirmed that all the specimens had sufficient performance in terms of far-infrared gland reflectivity, visible light transmittance, and scratch resistance.
Subsequently, Comparative Example 1 in which the metal composition of the metal oxide thin film was 100% by mass of niobium, Comparative Example 2 in which tin: niobium = 50% by mass: 50% by mass, and Comparative Example 3 in which 70% by mass: 30% by mass was used. In either case, peeling or cracking of the hard coat layer occurred in the durability test, and the judgment was “x”.

  From the above-mentioned results, by setting the metal composition of the metal oxide thin film to “tin main component / niobium: 3 to 20% by mass”, it is a laminated film in which a hard coat layer made of an organic material is formed, and has high durability. It was possible to obtain a laminated film suitable for window pasting applications having excellent infrared reflectivity, transparency and scratch resistance.

  Since the laminated film of the present invention has high durability and is excellent in far-infrared gland reflection performance, transparency, and scratch resistance, it can be suitably used for window glass in houses and buildings.

Claims (5)

In a laminated film in which a heat ray reflective layer and a hard coat layer are laminated in order on one side of a base material made of synthetic resin, the heat ray reflective layer has a multilayer structure in which metal thin films and metal oxide thin films are alternately laminated (metal thin film When the number of layers is “n”, the number of layers of the metal oxide thin film is “n + 1”). At least the metal oxide thin film in contact with the hard coat layer has tin as the main component of the metal component and niobium in the metal. A laminated film comprising 3 to 20% by mass. The laminated film according to claim 1, wherein a barrier layer is formed between the metal thin film and the metal oxide thin film which are heat ray reflective layers. The barrier layer formed between the metal thin film and the metal oxide thin film is a metal oxide containing at least one of tin and niobium, and has a low oxygen content as compared with the metal oxide thin film. The laminated film according to claim 1 or claim 2. The hard coat layer includes a crosslinked resin having one or more polar groups selected from the group consisting of a phosphate group, a sulfonic acid group, and an amide group, and has a thickness of 0.5 to 2.0 μm. The laminated film according to any one of claims 1 to 3. 5. A window pasting film in which an adhesive layer is formed on the side opposite to the heat ray reflective layer / hard coat layer forming surface of the laminated film according to any one of claims 1 to 4, wherein wavelength 5 measured from the surface of the hard coat layer A film for window pasting characterized in that a far-infrared reflectance of 5 to 50 μm is 85% or more and a solar heat penetration rate is 0.6 or less.