JP2013086987A - Laminated glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated glass in which occurrence of wrinkles or the like in a functional film is suppressed.SOLUTION: The laminated glass includes a resin film interposed via an adhesive layer between a first glass substrate and a second glass substrate, and also has an approximately annular concealing part near an outer circumference. The resin film shows a heat shrinkage percentage of over 1% and less than 2% in a direction where the heat shrinkage percentage is maximum, and shows a heat shrinkage percentage of over 1% and less than 2% in a direction orthogonal to the above direction. The cut end of the resin film is disposed within each 10 mm range with respect to an inner circumference of the concealing part in a direction toward the cut end of the laminated glass and in the opposite direction thereto, when the laminated glass is viewed from front. The above heat shrinkage percentage of the resin film is measured when the film is held at 150°C for 30 minutes.

Description

  The present invention relates to laminated glass, and more particularly to laminated glass in which a resin film is sandwiched between a pair of glass substrates.

  Conventionally, as a laminated glass used for a windshield of a vehicle or the like, a glass having an infrared reflection film sandwiched between a pair of glass substrates via an adhesive layer is known. The infrared reflective film is obtained by forming an infrared reflective film on a resin film serving as a base material. Such laminated glass, for example, superimposes a glass substrate, an adhesive sheet, an infrared reflective film, an adhesive sheet, and a glass substrate in this order, and cuts and removes the infrared reflective film and the adhesive sheet protruding from the outer peripheral portion of the pair of glass substrates. Then, it is manufactured by heating and pressurizing the whole.

  In laminated glass, when the glass substrate is curved three-dimensionally, wrinkles are generated in the infrared reflecting film or cracks are generated in the infrared reflecting film. Reflectivity is also likely to decrease. In order to suppress wrinkles in the infrared reflective film and cracks in the infrared reflective film, for example, it is known to use an infrared reflective film having a specific heat shrinkage rate (see, for example, Patent Document 1).

  On the other hand, since it is easy to corrode when an infrared reflective film is provided up to the outer peripheral portion of the laminated glass, it is known that no infrared reflective film is provided on the outer peripheral portion. In addition, in order to suppress a rapid change in reflectance and transmittance when an infrared reflecting film is not provided on the outer peripheral portion, in order to suppress a sudden change in the reflectance and transmittance, in order from the outside, the annular opaque band and the fade-out band are overlapped with the fade-out band. It is known to provide an infrared reflecting film (see, for example, Patent Document 2).

JP 2009-35438 A JP-T-2002-528374

  As described above, it is known to use an infrared reflective film having a specific heat shrinkage rate in order to suppress wrinkles and the like in the infrared reflective film. However, when such an infrared reflective film is provided so as to reach the outer peripheral portion of the laminated glass, with the thermal contraction of the infrared reflective film, a state in which air is caught between the glass substrates near the outer peripheral portion and becomes white, A so-called foamed state is likely to occur, and distortion is likely to occur in the fluoroscopic image when the laminated glass is seen through. In particular, when the glass substrate has a large curvature, such foaming and distortion of the fluoroscopic image are likely to occur.

  It is conceivable that the infrared reflection film is not provided on the outer peripheral portion of the laminated glass, for example, so as to overlap the fade-out band, but when it is provided only to overlap the fade-out band, the wrinkles of the infrared reflection film in the vicinity of the outer peripheral portion are not necessarily sufficient. Cannot be sufficiently suppressed, particularly when the glass substrate has a large curvature.

  The present invention has been made to solve the above-described problems, and suppresses wrinkling and foaming of a functional film such as an infrared reflective film in the vicinity of the outer peripheral portion and distortion of a fluoroscopic image even when the curvature is large. The object is to provide a laminated glass with good appearance and visibility.

  In the laminated glass of the present invention, a resin film is sandwiched between the first glass substrate and the second glass substrate via an adhesive layer, and a substantially annular concealing portion is provided in the vicinity of the outer peripheral portion. Here, the resin film is a film made only of a resin material, and may be provided alone in the laminated glass, or a functional film is formed on the surface thereof and provided as a part of the functional film. Also good. The concealing part is an opaque colored layer. The resin film has a heat shrinkage rate in the direction in which the heat shrinkage rate is maximum of more than 1% and less than 2%, and a heat shrinkage rate in a direction perpendicular to the direction of more than 1% and less than 2%. Moreover, when the laminated glass is viewed from the front, the cut end of the resin film is disposed within a range of 10 mm in each of the cut end direction of the laminated glass and the opposite direction to the inner peripheral portion of the concealing portion. However, the heat shrinkage rate of the resin film is that when the resin film is held at 150 ° C. for 30 minutes.

  According to the laminated glass of the present invention, the resin film having a thermal shrinkage rate in a specific range is used, and the cut end of the resin film is disposed in the specific range with respect to the inner peripheral portion of the concealing portion, thereby curving. Even if it is large, wrinkles and foaming in the vicinity of the outer peripheral portion and distortion of the fluoroscopic image can be suppressed, and the appearance and visibility can be improved.

The top view which shows one Embodiment of the laminated glass of this invention. The AA sectional view taken on the line of the laminated glass shown in FIG. Sectional drawing which shows an example of an infrared reflective film. Explanatory drawing which shows the measuring method of the thermal contraction rate of a resin film.

Hereinafter, the laminated glass of this invention is demonstrated with reference to drawings.
FIG. 1 shows an embodiment of a laminated glass having a resin film, and is a plan view showing an embodiment of a laminated glass having a resin film as a part of an infrared reflecting film that is a functional film. FIG. 2 is a cross-sectional view of the laminated glass shown in FIG.

  In the laminated glass 1, a functional film as an infrared reflective film 5 as a functional film is sandwiched between a first glass substrate 2 and a second glass substrate 3 with an adhesive layer 4 interposed therebetween. The infrared reflective film 5 is configured by forming an infrared reflective film 52 as a functional film on a resin film 51. A substantially annular concealing portion 6 is provided on the inner surface in the vicinity of the outer peripheral portion of the second glass substrate 3.

  The laminated glass 1 is used, for example, on the first glass substrate 2 side as the outside of the vehicle, and the concealing portion 6 is provided on the inner surface of the second glass substrate 3. It does not need to be provided on the surface, and may be provided on the inner surface of the first glass substrate 2 or the outer surface of the second glass substrate 3.

  The resin film 51 in such a laminated glass 1 has a heat shrinkage rate in the direction in which the heat shrinkage rate is maximized exceeding 1% and less than 2%, and a heat shrinkage rate in the direction orthogonal to the direction exceeding 1%. Less than%. However, the thermal shrinkage rate of the resin film 51 is that when the resin film 51 is held at 150 ° C. for 30 minutes.

  As shown in FIGS. 1 and 2, the infrared reflective film 5 having the resin film 51 has a cut end 5 a cut from the inner peripheral portion 6 a of the concealing portion 6 when the laminated glass 1 is viewed from the front. It arrange | positions in the range of 10 mm of the direction of the edge 1a, and the direction opposite to this direction, respectively. That is, the range in which the cut end 5a of the infrared reflecting film 5 can be disposed is 10 mm in the direction of the cut end 1a of the laminated glass 1 and the cut end 1a of the laminated glass 1 with respect to the inner peripheral portion 6a of the concealing portion 6. The range is 10 mm in the opposite direction to the direction.

  Here, in FIGS. 1 and 2, the cut end 5 a of the infrared reflecting film 5 is disposed within a predetermined range that is opposite to the direction of the cut end 1 a of the laminated glass 1 with respect to the inner peripheral portion 6 a of the concealing portion 6. This is an example. Thus, the cut end 5a of the infrared reflective film 5 may be disposed so as not to overlap the inner peripheral portion 6a of the concealing portion 6 when the laminated glass 1 is viewed from the front, and although not shown, the concealing portion 6 is not shown. It may be arranged so as to overlap with the inner peripheral part 6a. However, in any case, the cut end 5a of the infrared reflective film 5 is disposed within a range of 10 mm on both sides of the inner peripheral portion 6a of the concealing portion 6.

  As described above, the heat shrinkage rate in the direction in which the heat shrinkage rate of the resin film 51 is maximum and the direction orthogonal to the direction are set within the predetermined ranges, respectively, and the cut end is formed in the inner peripheral portion 6a of the concealing portion 6 On the other hand, by disposing within a predetermined range, air is formed between the wrinkles of the infrared reflecting film 5 in the vicinity of the outer peripheral portion of the laminated glass 1 and between the first glass substrate 2 and the second glass substrate 3 in the vicinity of the outer peripheral portion. Foaming that becomes engulfed in white and distortion of the fluoroscopic image when the laminated glass 1 is seen through can be suppressed, and the appearance and visibility can be improved. In particular, when the degree of curvature of the laminated glass 1 is large, wrinkles, foaming and distortion of the fluoroscopic image in the vicinity of the outer peripheral portion can be effectively suppressed.

  The first glass substrate 2 and the second glass substrate 3 can be general inorganic transparent glass plates, and are not particularly limited as long as they are used for vehicles or the like. A molded float glass plate is used. Moreover, the 1st glass substrate 2 and the 2nd glass substrate 3 can also be used as organic transparent boards, such as a polycarbonate board and a polymethylmethacrylate board, for example. Although the thickness of the 1st glass substrate 2 and the 2nd glass substrate 3 can be selected suitably, 1.8-2.5 mm is preferable normally. For example, the first glass substrate 2 and the second glass substrate 3 may be coated with a water repellent function, a hydrophilic function, an antifogging function, and the like.

  The degree of curvature of the first glass substrate 2 and the second glass substrate 3 is not necessarily limited, but the maximum bending depth when the laminated glass 1 is used is preferably 10 mm or more, more preferably 20 mm or more, and more preferably 30 mm or more. Further preferred. The maximum bending depth is also referred to as the double value, and is an index that represents the degree of bending. The larger the value, the larger the degree of bending, and wrinkles, foaming, and distortion of the fluoroscopic image occur near the outer periphery. It becomes easy to do. According to the present invention, wrinkles and foaming in the vicinity of the outer peripheral portion and distortion of the fluoroscopic image can be simultaneously and effectively suppressed particularly for those having a large degree of curvature. Here, the maximum bending depth (double value) is such that the laminated glass that is curved in a convex shape is arranged so that the convex side faces downward, and the midpoints of a pair of opposed long sides in this laminated glass are between When a straight line is drawn so as to connect, the length of the perpendicular drawn to the straight line from the deepest point at the bottom of the curved part is expressed in mm.

  A substantially annular concealing portion 6 is formed in the vicinity of the outer peripheral portion of at least one of the first glass substrate 2 and the second glass substrate 3. The concealing part 6 has a solid coating shape, and its width is usually in the range of 10 to 200 mm.

  Although not shown, a fade-out band portion may be provided in a portion opposite to the direction of the cut end 1 a of the laminated glass 1 with respect to the concealing portion 6. In the case where the fade-out band portion is provided, for example, a large number of dots are gathered. Examples of the dot include shapes such as a circle, a rectangle, and a polygon, and the size is usually changed within a range of 0.001 to 10.00 mm. The fade-out band part 62 can also have a form other than a dot, for example, a plurality of lines having different line widths. In addition, also when providing a fade-out band part, the cut end 5a of the infrared reflective film 5 is arrange | positioned on the basis of the inner peripheral part 6a of the concealing part 6 similarly to the case where a fade-out band part is not provided.

  The concealing portion 6 can be formed using a known material such as a colored ceramic paste and using a known manufacturing method. As the ink used for forming the concealing portion 6, for example, an ink in which dark pigment, glass frit, refractory filler, and resin such as ethyl cellulose are dispersed in a solvent is used. Usually, ink is printed in a predetermined pattern on a glass plate to be the first glass substrate 2 or the second glass substrate 3, and after pre-baking by drying or ultraviolet irradiation, the glass plate is cut with a cutting machine. The first glass substrate 2 or the second glass substrate 3 is cut out. Then, the cut glass plate is placed on a predetermined mold in the bending step, heated to the glass softening point or higher in a heating furnace, cooled, and bent into a desired shape. The concealing part 6 is completely baked on the glass plate by being heated and cooled in the bending step.

  The adhesive layer 4 is preferably one that can effectively bond the first glass substrate 2 or the second glass substrate 3 and the infrared reflective film 5 and can sufficiently ensure the visibility of the laminated glass 1, for example, thermoplastic. What consists of a pair of adhesive sheet which shape | molded the resin composition which has resin as a main component in a sheet form is preferable. The thickness of such an adhesive sheet is preferably 0.1 to 1 mm, and more preferably 0.2 to 0.8 mm.

  Examples of the thermoplastic resin include plasticized polyvinyl acetal resin, plasticized polyvinyl chloride resin, saturated polyester resin, plasticized saturated polyester resin, polyurethane resin, plasticized polyurethane resin, and ethylene-vinyl acetate. The thermoplastic resin conventionally used for this kind of use, such as polymer system resin and ethylene-ethyl acrylate copolymer system resin, is mentioned.

  Among these, it is possible to obtain a plastic having an excellent balance of various properties such as transparency, weather resistance, strength, adhesion, penetration resistance, impact energy absorption, moisture resistance, heat insulation, and sound insulation. A polyvinyl acetal resin is preferably used. These thermoplastic resins may be used alone or in combination of two or more. “Plasticization” in the plasticized polyvinyl acetal resin means that it is plasticized by adding a plasticizer. The same applies to other plasticized resins.

  The polyvinyl acetal-based resin is a polyvinyl formal resin obtained by reacting polyvinyl alcohol (hereinafter sometimes referred to as “PVA” if necessary) and formaldehyde, and a narrow meaning obtained by reacting PVA and acetaldehyde. Polyvinyl acetal resin, polyvinyl butyral resin obtained by reacting PVA and n-butyraldehyde (hereinafter sometimes referred to as “PVB” if necessary), etc., in particular, transparency, weather resistance, PVB is preferred as it is excellent in balance of various properties such as strength, adhesive strength, penetration resistance, impact energy absorption, moisture resistance, heat insulation, and sound insulation. These polyvinyl acetal resins may be used alone or in combination of two or more.

  The PVA used for the synthesis of the polyvinyl acetal resin is not particularly limited, but preferably has an average degree of polymerization of 200 to 5000, more preferably 500 to 3000. The polyvinyl acetal resin is not particularly limited, but preferably has a degree of acetalization of 40 to 85 mol%, more preferably 50 to 75 mol%. The polyvinyl acetal resin preferably has a residual acetyl group content of 30 mol% or less, more preferably 0.5 to 24 mol%.

  Examples of the plasticizer used for plasticizing a thermoplastic resin, preferably a polyvinyl acetal resin, include, for example, organic acid ester plasticizers such as monobasic organic acid esters and polybasic organic acid esters, And phosphoric acid plasticizers such as organic phosphoric acid and organic phosphorous acid.

  The amount of the plasticizer added to the thermoplastic resin, preferably the polyvinyl acetal resin, varies depending on the average degree of polymerization of the thermoplastic resin, the average degree of polymerization of the polyvinyl acetal resin, the degree of acetalization, and the amount of residual acetyl groups. The amount of the plasticizer is preferably 10 to 80 parts by mass with respect to 100 parts by mass of the thermoplastic resin, preferably the polyvinyl acetal resin. When the addition amount of the plasticizer relative to 100 parts by mass of the thermoplastic resin, preferably polyvinyl acetal resin is less than 10 parts by mass, plasticization of the thermoplastic resin, preferably polyvinyl acetal resin becomes insufficient, and molding is not possible. On the contrary, if the amount of the plasticizer added exceeds 100 parts by mass of the thermoplastic resin, preferably polyvinyl acetal resin, the strength of the resulting adhesive layer may be insufficient. .

  In addition to the above thermoplastic resins, the resin composition is, for example, an adhesion modifier, a coupling agent, a surfactant, an antioxidant, a thermal stabilizer, a light stabilizer, an ultraviolet absorber, an infrared absorber, a fluorescent agent, a dehydrating agent. One kind or two or more kinds of various additives such as an agent, an antifoaming agent, an antistatic agent and a flame retardant may be contained.

  As shown in FIG. 3, the infrared reflective film 5 is obtained by forming an infrared reflective film 52 on a resin film 51 serving as a base material. The resin film 51 has a thermal shrinkage rate in the direction in which the thermal shrinkage rate is maximized exceeding 1% and less than 2%, and a thermal shrinkage rate in a direction orthogonal to the direction is more than 1% and less than 2%. However, the thermal shrinkage rate of the resin film 51 is that when the resin film 51 is held at 150 ° C. for 30 minutes. Note that the thermal contraction rate in the direction in which the thermal contraction rate is maximum and the thermal contraction rate in the direction orthogonal to the direction do not necessarily have to be different from each other, and may be the same.

  Generally, the resin film 51 is manufactured by extending the constituent material into a film shape. About what is manufactured by such extending | stretching, the stress by extending | stretching exists as a residual stress, and it heat-shrinks by the heating-pressing at the time of manufacturing the laminated glass 1 with this residual stress. In particular, the film tends to shrink in the film forming direction, which is the main stretching direction, so-called MD direction.

  By setting the heat shrinkage rate in the direction in which the heat shrinkage rate of the resin film 51 is maximum and the direction perpendicular to the direction to more than 1% and less than 2%, wrinkles generated near the outer peripheral portion of the laminated glass 1 Foaming and distortion of the fluoroscopic image can be suppressed. That is, when the heat shrinkage rate in either direction is 1% or less, the heat shrinkage rate is too small, so that wrinkles are likely to occur in the vicinity of the outer peripheral portion of the laminated glass 1, and particularly when the laminated glass 1 has a large curvature. Since it cannot follow the curve, wrinkles are likely to occur. Further, when the thermal shrinkage rate in any direction is 2% or more, the thermal shrinkage rate is too large, so that foaming is likely to occur in the vicinity of the outer peripheral portion of the laminated glass 1, and distortion of the fluoroscopic image is also likely to occur. In particular, foaming and distortion of the fluoroscopic image are likely to occur when the laminated glass 1 has a large curvature.

  The resin film 51 has a heat shrinkage rate in the direction in which the heat shrinkage rate is maximum of 1.1% to 1.9%, and a heat shrinkage rate in a direction orthogonal to the direction of 1.1% to 1.9%. The heat shrinkage rate in the direction in which the heat shrinkage rate is maximum is 1.3% to 1.7%, and the heat shrinkage rate in the direction perpendicular to the direction is 1.3% to 1. More preferably, it is 7% or less. The heat shrinkage rate can be adjusted by appropriately adjusting the stretched state during production.

Here, the thermal shrinkage rate of the resin film 51 is that when the resin film 51 is held at 150 ° C. for 30 minutes as described above. The heat treatment for measuring the heat shrinkage rate is performed in a state suspended in a heating oven (no load state). The heat shrinkage rate is calculated by the following formula (1), where L _{1 is} the length before heat treatment and L ₂ is the length after heat treatment. Here, the lengths L ₁ and L ₂ are lengths in the direction in which the thermal shrinkage rate in the resin film 51 is maximized or in the direction perpendicular to the direction.
Thermal contraction rate = ((L ₁ −L ₂ ) / L ₁ ) × 100 [%] (1)

Specifically, the thermal contraction rate can be obtained as follows.
First, a strip-shaped test piece 55 as shown in FIG. 4 is cut out from the resin film 51 along a direction in which the thermal shrinkage rate is maximum or a direction orthogonal to the direction. The test piece 55 has a length of 150 mm and a width of 20 mm, for example. A pair of reference lines 56 and 57 are written on the test piece 55 with an interval of about 100 mm in the longitudinal direction, and a length L between the reference lines 56 and 57 is measured. This length L corresponds to L ₁ in the above formula (1).

The test piece 55 is suspended vertically in a hot air circulation oven, heated to 150 ° C. and held for 30 minutes, naturally cooled to room temperature and held for 60 minutes, and then the length L is measured again. This length L corresponds to L ₂ in the above formula (1). Then, the thermal contraction rate can be calculated by substituting the obtained length L (L ₁ , L ₂ ) into the above formula (1).

  Usually, the film forming direction corresponds to the direction in which the heat shrinkage rate is maximized. Therefore, if the film forming direction is known in advance, the heat shrinkage rate obtained for the film forming direction is the maximum heat shrinkage rate. The heat shrinkage rate in the direction of For the same reason, the thermal contraction rate obtained in the direction orthogonal to the film forming direction can be set as the thermal contraction rate in the direction orthogonal to the direction in which the thermal contraction rate is maximized.

  The constituent material of the resin film 51 is not particularly limited as long as a predetermined heat shrinkage can be obtained. For example, polycarbonate, polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide , Polyethersulfone, polyarylate, nylon, cycloolefin polymer and the like.

  Usually, polyethylene terephthalate (PET) is suitably used because it has a relatively high strength and can suppress damage during the production of the laminated glass 1. Although the thickness of the resin film 51 is not necessarily limited, 5-200 micrometers is preferable, 25-125 micrometers is more preferable, and 50-100 micrometers is further more preferable.

  For example, the infrared reflective film 52 is formed by alternately stacking (2n + 1) layers of oxide layers 53 and metal layers 54 (where n is an integer of 1 or more and 4 or less). In addition, about what is shown in FIG. 3, it is a thing of n = 1, ie, the thing whose total number of layers of the oxide layer 53 and the metal layer 54 is three. Although not shown, a protective layer or the like may be formed on the infrared reflective film 52.

  The oxide layer 53 in the infrared reflective film 52 generally has a refractive index of 1.7 to 2.6 (refractive index at a wavelength of 550 nm, the same shall apply hereinafter), particularly preferably 1.8 to 2.6, such as bismuth oxide. In addition, a layer mainly containing a metal oxide such as tin oxide, zinc oxide, tantalum oxide, niobium oxide, tungsten oxide, titanium oxide, zirconium oxide, or indium oxide, or a layer containing a mixture thereof is preferable. In particular, a layer mainly composed of zinc oxide or a layer mainly composed of indium oxide is preferable. As a layer mainly composed of zinc oxide, an oxide layer of zinc oxide alone or at least one element selected from tin, aluminum, chromium, titanium, silicon, boron, magnesium, indium, and gallium is used. Examples include a layer mainly containing zinc oxide, and examples of the layer mainly containing indium oxide include a layer mainly containing indium oxide containing tin.

  Among these, zinc oxide or tin, aluminum, chromium, titanium, silicon, boron, magnesium, indium, and gallium are selected from the point that the metal layer 54 can be formed stably and with high crystallinity. A layer mainly composed of zinc oxide containing one or more elements, particularly zinc oxide containing at least one of aluminum and titanium is preferable. Each oxide layer 53 may be a single layer or multiple layers.

  The metal layer 54 is preferably composed mainly of silver, for example, composed of only silver or composed of an alloy composed mainly of silver. Constituent components other than silver in the metal layer 54 are, for example, palladium, gold, copper, etc., and the content of these constituent components other than silver is preferably 0.3 to 10 atomic% in total.

  The thicknesses of the oxide layer 53 and the metal layer 54 vary depending on the total number of layers and the constituent materials of each layer. For example, each oxide layer 53 is 5 to 100 nm, each metal layer 54 is 5 to 20 nm, The total layer thickness of the oxide layer 53 and the metal layer 54 is 50 to 400 nm, more preferably 150 to 300 nm.

  The infrared reflective film 52 may be composed of a high refractive index layer and a low refractive index layer instead of the oxide layer 53 and the metal layer 54. Usually, the total number of the high refractive index layer and the low refractive index layer is 3 or more, the thickness of the high refractive index layer is 70 to 150 nm, and the thickness of the low refractive index layer is 100 to 200 nm.

  The high refractive index layer is, for example, a dielectric having a refractive index of 1.9 or more, preferably 1.9 to 2.5, and specifically, tantalum oxide (refractive index: 2.0 to 2.2). , Titanium oxide (refractive index: 2.2 to 2.5), zirconium oxide (refractive index: 1.9 to 2.0), and hafnium oxide (refractive index: 1.95 to 2.15) The thing which consists of at least 1 sort (s) chosen from rate materials is mentioned.

  The low refractive index layer is, for example, a dielectric having a refractive index of 1.5 or less, preferably 1.2 to 1.5, specifically silicon oxide (refractive index: 1.44 to 1.4). 48) and at least one selected from low refractive index materials such as magnesium fluoride (refractive index: 1.35 to 1.41).

  The infrared film 5 may be a functional film made only of a resin material. In this case, the film material is composed of polyethylene terephthalate, polyethylene naphthalate, polymethyl methacrylate, polyethylene, polystyrene, polycarbonate, nylon, polyether sulfone, a mixture of polyvinylidene fluoride and polymethyl methacrylate, ethylene, and an unsaturated monocarboxylic acid. A desired function can be expressed by combining a copolymer, a copolymer of styrene and methyl methacrylate, and the like.

  As already described, when the laminated glass 1 is viewed from the front, the infrared reflecting film 5 has its cut end 5a in the direction of the cut end 1a of the laminated glass 1 and the direction with respect to the inner peripheral portion 6a of the concealing portion 6. Are arranged within a range of 10 mm in the opposite direction. Here, the cut edge 5a of the infrared reflective film 5 is disposed within the above-mentioned range, but it is not always necessary to be disposed at a constant distance from the inner peripheral part 6a of the concealing part 6 in the circumferential direction. As long as at least the entire circumference is disposed within the above range, the distance may change in the circumferential direction.

  When the cut end 5a of the infrared reflective film 5 is separated from the inner peripheral portion 6a of the concealing portion 6 in the direction of the cut end 1a of the laminated glass 1 by more than 10 mm, the shape of the infrared reflective film 5 is too large, so that the laminated glass 1 Wrinkles are likely to occur in the vicinity of the outer periphery of the glass, and particularly when the laminated glass 1 has a large curvature, wrinkles are likely to occur. Moreover, when the cut end 5a of the infrared reflective film 5 is separated from the inner peripheral portion 6a of the concealing portion 6 by more than 10 mm in the direction opposite to the cut end 1a of the laminated glass 1, the generation of wrinkles is suppressed. Since the distance between the cut end 5a of the reflective film 5 and the inner peripheral portion 6a of the concealing portion 6 is too large, it is not preferable from the viewpoints of appearance and visibility from the inside of the vehicle. The cut end 5a of the infrared reflecting film 5 is preferably disposed within a range of 5 mm from the inner peripheral portion 6a of the concealing portion 6 in the direction of the cut end 1a of the laminated glass 1 or in the opposite direction.

  The laminated glass 1 can be applied to automobiles, railways, ships, and the like, and is particularly suitable for automobile windshields. Laminated glass 1 is capable of suppressing wrinkles and foaming in the vicinity of the outer peripheral portion, and distortion of the fluoroscopic image, and particularly having a large curvature, suppressing wrinkles and foaming, and distortion of the fluoroscopic image, and has good appearance and visibility. Therefore, it is suitable for these uses, particularly for automobile windshields.

Next, the manufacturing method of the laminated glass 1 is demonstrated.
The laminated glass 1 includes, for example, a step of laminating a first adhesive sheet and a second adhesive sheet that become the adhesive layer 4 on both surfaces of the infrared reflective film 5 and heating and pressing to form a laminate, The first glass substrate 2 and the second glass substrate 3 are superposed on both surfaces and heated and pressed to form a laminated glass 1 (hereinafter referred to as a first method).

  Moreover, the laminated glass 1 makes the laminated body by superimposing the 1st glass substrate 2, the 1st adhesive sheet, the infrared reflective film 5, the 2nd adhesive sheet, and the 2nd glass substrate 3 in this order, for example. It can be manufactured through a step and a step of forming the laminated glass 1 by heating and pressing the laminate (hereinafter referred to as a second method).

  The laminated glass 1 is manufactured by laminating only a part of the constituent layers to form a laminated body as in the first method, and then bonding the first glass substrate 2 and the second glass substrate 3 to the laminated body. Alternatively, as in the second method, all the constituent layers may be laminated to form a laminated body, and then this may be manufactured by pressure bonding.

  In any of the manufacturing methods, as the infrared reflective film 5, the thermal shrinkage rate in the direction in which the thermal shrinkage rate is maximum is more than 1% and less than 2%, and the thermal shrinkage rate in the direction orthogonal to the direction is more than 1%. When it has a resin film 51 that is less than 2% and is finally crimped into a laminated glass 1, the cut end 5 a extends from the inner peripheral part 6 a of the concealing part 6 to the cut end 1 a of the laminated glass 1 and the Use a shape and a size that are within a range of 10 mm in the opposite direction.

  In the production of the laminate in the first method, the first adhesive sheet and the second adhesive sheet are superimposed on both surfaces of the infrared reflective film 5, respectively, for example, at a temperature of about 40 to 80 ° C. and a pressure of about 0.1. It can be performed by heating and pressing under a condition of ˜1.0 MPa.

  The pressure bonding in the first method is performed, for example, by putting the first glass substrate 2 and the second glass substrate 3 on both sides of the laminate in a vacuum bag such as a rubber bag, and applying pressure. It is heated to about 70 to 110 ° C. while pre-depressing while degassing so as to be about 1 to 36 kPa, and then heated and pressurized at a temperature of 120 to 150 ° C. and a pressure of about 0.98 to 1.47 MPa in an autoclave. be able to.

  On the other hand, for the pressure bonding in the second method, similarly, the laminate is put in a vacuum bag such as a rubber bag and heated to about 70 to 110 ° C. while degassing so that the pressure becomes about 1 to 36 kPa. After pre-bonding, it can be carried out by heating and pressurizing in an autoclave at a temperature of about 120 to 150 ° C. and a pressure of about 0.98 to 1.47 MPa.

Hereinafter, the present invention will be described in more detail with reference to examples.
Of the following Examples 1 to 6, Example 4 is an example of the present invention, and the others are comparative examples of the present invention.

(Example 1)
As a PET film, the heat shrinkage rate in the direction (film forming direction (MD direction)) having the maximum heat shrinkage rate is 1.0%, and the direction perpendicular to the direction (direction perpendicular to the film forming direction (TD direction)). (Commercial name: O321E100, UE82-HX-4, thickness 100 μm, manufactured by Mitsubishi Plastics, Inc.) was prepared. In addition, the heat shrinkage rate in the direction in which the heat shrinkage rate is maximized is an average of the heat shrinkage rates in the direction in which the heat shrinkage rates of the three PET films obtained by the measurement method are maximized. Similarly, the heat shrinkage rate in the orthogonal direction is the average of the heat shrinkage rates in the orthogonal direction for the three PET films.

On this PET film, as shown below, nine layers of Nb ₂ O ₅ layers to be high refractive index dielectric layers and SiO ₂ layers to be low refractive index dielectric layers are alternately laminated by magnetron sputtering as shown below. Thus, an infrared reflecting film was formed to obtain an infrared reflecting film.

Incidentally, each of _Nb 2 _{O 5} layer, NBO target (AGC ceramic trade name: NBO) using, while introducing a mixed gas of 5 vol% of oxygen gas to argon gas, 0.1 Pa of It was formed by performing pulse sputtering with a pressure of frequency 20 kHz, power density 5.1 W / cm ² , and inversion pulse width 5 μsec.

In addition, each SiO ₂ layer is introduced with a mixed gas in which 27 vol% oxygen gas is mixed with argon gas using a Si target, while a frequency of 20 kHz and a power density of 3.8 W / cm ² at a pressure of 0.3 Pa. It was formed by performing pulse sputtering with an inversion pulse width of 5 μsec.

The thickness of each Nb ₂ O ₅ layer and SiO ₂ layer is adjusted by changing the film formation time, and in order from the PET film side, Nb ₂ O ₅ layer (95 nm) / SiO ₂ layer (153 nm) / Nb ₂ O ₅ layers (95 nm) / SiO ₂ layer (153 nm) / Nb ₂ O ₅ layer (95 nm) / SiO ₂ layer (153 nm) / Nb ₂ O ₅ layer (95 nm) / SiO ₂ layer (25 nm) / Nb ₂ O ₅ layer (10 nm).

  Next, the first glass substrate, the first adhesive sheet, the infrared reflective film, the second adhesive sheet, and the second glass substrate were superposed in this order, and the ends were temporarily fixed to obtain a laminate.

  Here, the first glass substrate and the second glass substrate have three kinds of different curved states (model A (double value: 15 mm), model B (double value: 25 mm)) to be a vehicle windshield. Model C (double value: 35 mm)) was used. Further, the second glass substrate was provided with a substantially annular concealing portion having a width of 20 mm on the inner surface in the vicinity of the outer peripheral portion.

  When the infrared reflecting film is made of laminated glass, the cut end thereof reaches the outer periphery of the first glass substrate and the second glass substrate, that is, has a size that overlaps the entire concealing portion (cutback). None). The first adhesive sheet and the second adhesive sheet were PVB films (manufactured by Solusia Japan) having a thickness of 0.38 mm.

  Then, the laminate is put into a vacuum bag, deaerated so that the pressure gauge display is 100 kPa or less, heated to 120 ° C. and pre-pressed, and further autoclaved at a temperature of 135 ° C. and a pressure of 1.3 MPa for 60 minutes. And finally cooled to obtain a laminated glass.

(Example 2)
When the laminated glass is used as the infrared reflecting film, the entire circumference of the cut end is located in the direction opposite to the direction of the cut end of the laminated glass with respect to the inner peripheral part of the concealed part, Three types of laminated glass having different curved states in the same manner as in Example 1 except that one having a size within 10 mm from the inner peripheral portion, specifically, one having a size becoming 5 mm from the inner peripheral portion was used. Manufactured).

(Example 3)
As a PET film, the heat shrinkage rate in the direction in which the heat shrinkage rate is maximum (film forming direction (MD direction)) is 1.5%, and the heat shrinkage rate in the orthogonal direction (direction perpendicular to the film forming direction (TD direction)). 3% laminated glass (cut) in the same manner as in Example 1 except that 1.5% (trade name: O321E100, UE82-HX-5, thickness 100 μm) manufactured by Mitsubishi Plastics Co., Ltd. was used. No back) was produced.

(Example 4)
When the laminated glass is used as the infrared reflecting film, the entire circumference of the cut end is located in the direction opposite to the direction of the cut end of the laminated glass with respect to the inner peripheral part of the concealed part, Three types of laminated glass having different curved states in the same manner as in Example 3 except that one having a size within 10 mm from the inner peripheral portion, specifically, one having a size becoming 5 mm from the inner peripheral portion was used. Manufactured).

(Example 5)
As a PET film, the heat shrinkage rate in the direction (film forming direction (MD direction)) in which the heat shrinkage rate is maximum is 2.0%, and the heat shrinkage rate in the orthogonal direction (direction perpendicular to the film forming direction (TD direction)). 3% laminated glass (cut) in the same manner as in Example 1 except that 2.0% (made by Mitsubishi Plastics, trade name: O321E100, UE82-HX-6, thickness 100 μm) was used. No back) was produced.

(Example 6)
When the laminated glass is used as the infrared reflecting film, the entire circumference of the cut end is located in the direction opposite to the direction of the cut end of the laminated glass with respect to the inner peripheral part of the concealed part, Three types of laminated glass having different curved states in the same manner as in Example 5 except that a glass having a size within 10 mm from the inner periphery, specifically a glass having a size of 5 mm from the inner periphery, was used. Manufactured).

  Next, the following items were evaluated for the laminated glasses of Examples 1 to 6. The results are shown in Table 1.

(Wrinkle)
About the manufactured laminated glass, the generation | occurrence | production of the wrinkle of the infrared reflective film in the outer peripheral part vicinity was observed visually. In the table, “None” indicates that no wrinkles were observed on the infrared reflecting film, “Yes” indicates that wrinkles were observed on the infrared reflecting film, and “Noticeably” indicates wrinkles on the infrared reflecting film. The occurrence was remarkable.
(Foam)
About the manufactured laminated glass, the presence or absence of whitening by the entrainment of the air in the outer peripheral part vicinity was observed visually. In the table, “None” indicates that no whitening was observed, “Slightly” indicates that whitening occurred in a part of the circumferential direction of the laminated glass, and “Yes” indicates that The occurrence of whitening was observed in about half of the circumferential direction of the outer periphery of the glass, and “notably present” indicates that the occurrence of whitening was observed in almost the entire circumferential direction of the laminated glass. .
(Transparent distortion)
About the manufactured laminated glass, distortion of the target object (transparent image) when the target object was seen through through the part provided with the infrared reflective film in the vicinity of the outer peripheral part was visually evaluated. In the table, “None” indicates that no distortion was observed in the fluoroscopic image, “Slightly present” indicates that distortion was observed only when the fluoroscopic image was viewed from a nearly parallel angle, and “Yes”. Indicates that the occurrence of distortion was observed when the perspective image was viewed from any angle.

  As is clear from Table 1, by using a resin film having a predetermined heat shrinkage rate and disposing the cut end of the infrared reflective film having the resin film at a predetermined position with respect to the inner peripheral portion of the concealing portion, In particular, for laminated glass having a large curvature, wrinkles, foaming and distortion of the fluoroscopic image in the vicinity of the outer peripheral portion can be suppressed, and the appearance and visibility can be improved.

  DESCRIPTION OF SYMBOLS 1 ... Laminated glass, 1a ... Cut end, 2 ... 1st glass substrate, 3 ... 2nd glass substrate, 4 ... Adhesive layer, 5 ... Infrared reflective film (functional film), 5a ... Cut end, 6 ... Concealment Part 6a ... inner peripheral part 51 ... resin film 52 ... infrared reflective film (functional film) 53 ... oxide layer 54 ... metal layer

Claims (3)

Between the first glass substrate and the second glass substrate, a resin film is sandwiched via an adhesive layer, and is a laminated glass having a substantially annular concealing portion in the vicinity of the outer periphery,
The resin film has a heat shrinkage rate in the direction in which the heat shrinkage rate is maximum of more than 1% and less than 2%, and a heat shrinkage rate in a direction perpendicular to the direction of more than 1% and less than 2%, When the laminated glass is viewed from the front, the cut end of the film is disposed within a range of 10 mm in each of the cut end direction of the laminated glass and the opposite direction to the inner peripheral portion of the concealing portion. Laminated glass.
However, the heat shrinkage rate of the resin film is that when the resin film is held at 150 ° C. for 30 minutes.   The laminated glass according to claim 1, wherein the laminated glass has a maximum bending depth of 15 mm or more.   The laminated glass of Claim 1 or 2 which comprises the infrared reflective film which has the said resin film and the infrared reflective film formed on the said resin film.

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