Multilayer structure

Abstract

To reduce image strain due to heating in a multilayer structure including a glass layer, a metal layer, and a support medium.SOLUTION: This multilayer structure includes a metallic support medium, an adhesive layer laminated on the support medium, a metal layer laminated on the adhesive layer, and a glass layer laminated on the metal layer, wherein the thickness of the glass layer is 10 μm or over and 300 μm or under.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a multi-layer structure. [Background technology]

[0002] A multilayer structure in which two or more layers are laminated is known. One example is a multilayer structure in which a metal layer made of silver or the like is laminated on a thin glass layer (glass film). The thickness of this multilayer structure is, for example, within the range of 10 to 200 μm. This multilayer structure is obtained, for example, from a glass roll formed by a down-draw method. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-231744 A Summary of the Invention [Problem to be solved by the invention]

[0004] Since the above-mentioned thin glass layer is very fragile, cracks are likely to occur, and handling properties are poor. For example, a multilayer structure has been proposed in which a support is attached to one side of the glass layer to reinforce it and improve handling properties.

[0005] However, depending on the material of the support, there is a problem that the metal layer may curl due to thermal shrinkage caused by heating, or foaming may occur due to moisture evaporating from the support, resulting in distortion of the image.

[0006] The present invention has been made in view of the above-mentioned points, and has an object to reduce image distortion caused by heating in a multilayer structure including a glass layer, a metal layer, and a support. [Means for solving the problem]

[0007] This multilayer structure has a metal support, an adhesive layer laminated on the support, a metal layer laminated on the adhesive layer, and a glass layer laminated on the metal layer, and the thickness of the glass layer is 10 μm or more and 300 μm or less. Effect of the Invention

[0008] According to the disclosed technology, image distortion caused by heating can be reduced in a multilayer structure including a glass layer, a metal layer, and a support. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a cross-sectional view illustrating a multilayer structure according to the present embodiment. [Diagram 2] FIG. 2 is a diagram showing conditions and results of an example and a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and duplicated explanations may be omitted.

[0011] Fig. 1 is a cross-sectional view illustrating a multilayer structure according to the present embodiment. As shown in Fig. 1, the multilayer structure 1 has a support 10, a pressure-sensitive adhesive layer 20, a resin layer 30, a metal layer 40, an adhesive layer 50, and a glass layer 60. The pressure-sensitive adhesive layer 20, the resin layer 30, the metal layer 40, the adhesive layer 50, and the glass layer 60 are sequentially laminated on the upper surface 10a of the support 10. The resin layer 30 and the adhesive layer 50 are provided as necessary.

[0012] The planar shape of the multi-layer structure 1 (the shape when viewed from the normal direction of the upper surface 10a of the support 10) is, for example, a rectangular shape. However, this is not limited thereto, and the planar shape of the multi-layer structure 1 can be a circle, an ellipse, a combination of these, or any other appropriate shape.

[0013] The multilayer structure 1 can be used, for example, as a mirror. In the multilayer structure 1, the thickness of the glass layer 60 is 10 μm or more and 300 μm or less. In the multilayer structure 1, the thickness of the glass layer 60 is thin, and the distance between the surface of the glass layer 60 and the metal layer 40 is extremely short. Therefore, the multilayer structure 1 can resolve the problem of double images that is a problem with conventional plate glass, and can project a clear image.

[0014] Here, the materials and the like of each part of the multi-layer structure 1 will be described.

[0015] [Support] The support 10 supports the metal layer 40 and the glass layer 60. The metal layer 40 and the glass layer 60 are thin and have flexibility like a film when used alone, so that a uniform reflected image cannot be obtained within the plane. Therefore, in the multilayer structure 1, the metal layer 40 and the glass layer 60 are supported by the support 10, which is a rigid body, so that a uniform reflected image can be obtained within the plane.

[0016] In the multilayer structure 1, the support 10 is made of metal. Examples of the material of the support 10 include aluminum, stainless steel (SUS), and copper. The support 10 can be made of resin, but if the support 10 is made of a general resin, the metal layer 40 may curl due to thermal contraction caused by heating (for example, at 60°C for 24 hours), or the moisture contained in the resin may evaporate and cause foaming, which may distort the image. In the multilayer structure 1, the support 10 made of metal is used to solve such problems. That is, in the multilayer structure 1 having the support 10 made of metal, the metal layer 40 does not curl due to thermal contraction caused by heating, and foaming does not occur due to the evaporation of moisture caused by heating, so that a clear image can be projected without distortion.

[0017] The size and thickness of the support 10 can be various values. Let a be the length of the support 10 in the longitudinal direction, b be the thickness of the support 10, and E be the Young's modulus of the support 10. The stiffness parameter α is expressed as follows: α=E×(a×b 3 ) / 12, it is preferable that 0.1<α<40 is satisfied.

[0018] Here, the length a in the longitudinal direction is the length of the long side when the planar shape of the support 10 is rectangular, and the length of one side when the planar shape of the support 10 is square. Also, it is the major axis when the planar shape of the support 10 is elliptical, and it is the diameter when the planar shape of the support 10 is circular. Also, when the planar shape of the support 10 is other than these, the length a in the longitudinal direction is defined as the length of the longest straight line that can be drawn continuously within the planar shape of the support 10.

[0019] If the stiffness parameter α of the support 10 is within the range of 0.1<α<40, the multi-layer structure 1 can obtain the required stiffness as a whole and can be lightweight enough to be portable. In other words, if the support 10 is made of metal and the stiffness parameter α is within the range of 0.1<α<40, the multi-layer structure 1 can project a clear image without distortion, and the multi-layer structure 1 can obtain the required stiffness as a whole and can be lightweight enough to be portable.

[0020] For example, when aluminum, SUS, or copper is used as the support 10 and the planar shape of the support 10 is an A4 size rectangle, the thickness of the support 10 is preferably 1 mm or more and 2 mm or less. Within this range, 0.1<α<40 is satisfied, and the multi-layer structure 1 can project a clear image without distortion, and the multi-layer structure 1 as a whole can obtain the necessary rigidity and can be lightweight enough to be portable. This allows the multi-layer structure 1 to be used, for example, as a portable mirror.

[0021] If the objective is to project a clear image without distortion and portability is not the objective, the stiffness parameter α of the support 10 may be outside the range of 0.1<α<40.

[0022] [Adhesive layer] The adhesive layer 20 is laminated on the support 10. In the example of FIG. 1, the adhesive layer 20 is provided between the support 10 and the resin layer 30, but when the multilayer structure 1 does not have the resin layer 30, the adhesive layer 20 is provided between the support 10 and the metal layer 40. Any appropriate adhesive is used as the adhesive layer 20. Examples of materials for the adhesive layer 20 include acrylic adhesives, silicone adhesives, and rubber adhesives. The thickness of the adhesive layer 20 is not particularly limited, but is, for example, about 5 μm or more and 500 μm or less.

[0023] [Resin layer] The resin layer 30 is laminated on the support 10 via the adhesive layer 20. The resin layer 30 is composed of one layer or multiple layers. When the resin layer 30 is composed of multiple layers, it is preferable to laminate them with an adhesive layer having an adhesive function interposed therebetween. The total thickness of the resin layer 30 may be 20 μm or more and 1000 μm or less from the viewpoint of flexibility, preferably 25 μm or more and 500 μm or less, more preferably 50 μm or more and 200 μm or less. When the resin layer 30 is composed of one layer, the thickness of the resin layer 30 can be, for example, in the range of 20 μm or more and 150 μm or less.

[0024] Examples of materials for the resin layer 30 include polyester-based resins such as polyethylene terephthalate-based resins and polyethylene naphthalate-based resins, cycloolefin-based resins such as norbornene-based resins, polyethersulfone-based resins, polycarbonate-based resins, acrylic-based resins, polyolefin-based resins, polyimide-based resins, polyamide-based resins, polyimideamide-based resins, polyarylate-based resins, polysulfone-based resins, polyetherimide-based resins, cellulose-based resins, and urethane-based resins.

[0025] The resin layer 30 is provided as necessary, and providing the resin layer 30 has the effect of improving the handleability of the multilayer structure 1. In addition, lamination of the resin layer 30 has the effect of preventing the occurrence of cracks in the glass layer 60 due to piercing or the like. Furthermore, the resin layer 30 is sufficiently thin compared to the support 10, and the amount of volatile gas generated by heating is small, so that problems such as image distortion do not occur.

[0026] [Metal layer] The metal layer 40 is laminated on the adhesive layer 20 via the resin layer 30. When the multilayer structure 1 does not have the resin layer 30, the metal layer 40 is laminated directly on the adhesive layer 20. The metal layer 40 is a layer that reflects visible light incident through the glass layer 60 and the adhesive layer 50. The material of the metal layer 40 is preferably a material with high visible light reflectance, such as aluminum, silver, and silver alloys. The thickness of the metal layer 40 is not particularly limited, but is, for example, about 10 nm or more and 500 nm or less. The metal layer 40 can be formed on the upper surface of the resin layer 30 by, for example, a sputtering method, a vapor deposition method, a plating method, or the like.

[0027] The metal layer 40 may be formed on the lower surface of the glass layer 60 by, for example, a sputtering method, a vapor deposition method, a plating method, etc. In this case, the adhesive layer 50 is not necessary.

[0028] [Adhesive layer] The adhesive layer 50 is formed from a material with high visible light transmittance. The thickness of the adhesive layer 50 is, for example, 0.1 μm or more and 25 μm or less. For example, an acrylic adhesive, a silicone adhesive, a rubber adhesive, an ultraviolet-curable acrylic adhesive, an ultraviolet-curable epoxy adhesive, a thermosetting epoxy adhesive, a thermosetting melamine adhesive, a thermosetting phenol adhesive, an ethylene vinyl acetate (EVA) intermediate film, a polyvinyl butyral (PVB) intermediate film, etc. can be used as the adhesive layer 50.

[0029] In this specification, the term "adhesive" refers to a layer that has adhesive properties at room temperature and adheres to an adherend with light pressure. Therefore, even when an adherend that has been stuck to the adhesive is peeled off, the adhesive retains practical adhesive strength. On the other hand, the term "adhesive" refers to a layer that can bond substances by being interposed between them. Therefore, when an adherend that has been stuck to the adhesive is peeled off, the adhesive no longer has practical adhesive strength.

[0030] [Glass layer] The glass layer 60 is laminated on the metal layer 40 via the adhesive layer 50. There is no particular limitation on the glass layer 60, and an appropriate one can be adopted depending on the purpose. The glass layer 60 can be classified according to composition, for example, soda-lime glass, borate glass, aluminosilicate glass, quartz glass, etc. Also, according to the alkali component, it can be classified as non-alkali glass or low-alkali glass. The alkali metal component of the above glass (for example, Na 2 OK 2 O, Li 2 The content of O) is preferably 15% by weight or less, and more preferably 10% by weight or less.

[0031] Considering the surface hardness, airtightness, and corrosion resistance of glass, the thickness of the glass layer 60 is preferably 10 μm or more. Since it is desirable for the glass layer 60 to have flexibility like a film, the thickness of the glass layer 60 is preferably 300 μm or less. The thickness of the glass layer 60 is more preferably 20 μm to 200 μm, and particularly preferably 30 μm to 150 μm.

[0032] The glass layer 60 preferably has a light transmittance of 85% or more at a wavelength of 550 nm. The glass layer 60 preferably has a refractive index of 1.4 to 1.65 at a wavelength of 550 nm. The glass layer 60 preferably has a density of 2.3 g / cm 3 ~3.0g / cm 3 and more preferably 2.3 g / cm 3 ~2.7g / cm 3 It is.

[0033] The method for forming the glass layer 60 is not particularly limited, and an appropriate method can be adopted depending on the purpose. Typically, the glass layer 60 can be produced by melting a mixture containing a main raw material such as silica or alumina, an antifoaming agent such as mirabilite or antimony oxide, and a reducing agent such as carbon at a temperature of about 1400°C to 1600°C, forming it into a thin plate, and then cooling it. Examples of the method for forming the glass layer 60 include a slot downdraw method, a fusion method, and a float method. The glass layer formed into a plate by these methods may be chemically polished with a solvent such as hydrofluoric acid as necessary to make it thinner or to increase the smoothness.

[0034] The upper surface of the glass layer 60 (the surface on which the adhesive layer 50 is not formed) may be provided with a functional layer such as an antifouling layer, an antireflection layer, a conductive layer, a reflective layer, or a decorative layer.

[0035] [Example 1] In Example 1, a multilayer structure was produced having a support, an adhesive layer laminated on the support, a metal layer laminated on the adhesive layer, and a glass layer laminated on the metal layer. The multilayer structure was then left in an environment at a temperature of 60° C. for 24 hours, and the occurrence of curling and foaming was confirmed.

[0036] The planar shape of each component of the multilayer structure was an A4 size rectangle. The support was made of aluminum with a thickness of 2 mm. The adhesive layer was 20 μm thick, the metal layer was 0.1 μm thick, and the glass layer was 100 μm thick.

[0037] [Example 2] In Example 2, a multi-layer structure was produced in the same manner as in Example 1, except that aluminum having a thickness of 1.5 mm was used as the support, and the same confirmation as in Example 1 was carried out.

[0038] [Example 3] In Example 3, a multilayer structure was produced in the same manner as in Example 1, except that aluminum having a thickness of 1 mm was used as the support, and the same confirmation as in Example 1 was carried out.

[0039] [Example 4] In Example 4, a multilayer structure was produced in the same manner as in Example 1, except that SUS having a thickness of 1 mm was used as the support, and the same confirmation as in Example 1 was carried out. [Example 5] In Example 5, a multilayer structure was produced in the same manner as in Example 1 except that copper having a thickness of 1 mm was used as the support, and the same confirmation as in Example 1 was carried out.

[0040] [Example 6] In Example 6, a multi-layer structure was produced in the same manner as in Example 1, except that aluminum having a thickness of 0.5 mm was used as the support, and the same confirmation as in Example 1 was carried out.

[0041] [Example 7] In Example 7, a multilayer structure was produced in the same manner as in Example 1, except that aluminum having a thickness of 3 mm was used as the support, and the same confirmation as in Example 1 was carried out.

[0042] [Comparative Example 1] In Comparative Example 1, a multilayer structure was produced in the same manner as in Example 1 except that a polycarbonate substrate having a thickness of 2 mm was used as the support, and the same confirmation as in Example 1 was carried out.

[0043] [Comparative Example 2] In Comparative Example 2, a multilayer structure was produced in the same manner as in Example 1 except that an acrylic having a thickness of 2 mm was used as the support, and the same confirmation as in Example 1 was carried out.

[0044] The conditions and results of Examples 1 to 7 and Comparative Examples 1 and 2 are summarized in Fig. 2. In addition, the stiffness parameter α was calculated for each of the supports used in Examples 1 to 7 and Comparative Examples 1 and 2, and is also summarized in Fig. 2.

[0045] 2, it was confirmed that the use of a metal support prevented curling or bubbling due to heating. On the other hand, in Comparative Examples 1 and 2, which used a resin support, curling and bubbling due to heating were confirmed. In other words, the effect of the metal support was confirmed.

[0046] It was also found that the multi-layer structure of Example 6, in which the stiffness parameter α was less than 0.1, had insufficient stiffness and could bend. It was also found that the multi-layer structure of Example 7, in which the stiffness parameter α was more than 40, was not sufficiently lightweight. From these results, it can be said that it is preferable to satisfy 0.1<α<40 in order to obtain the necessary stiffness for the entire multi-layer structure and to achieve a lightweight structure that can be carried around. It can also be said that when the planar shape of the multi-layer structure is an A4-sized rectangle, the thickness of the metal support is preferably 1 mm or more and 2 mm or less.

[0047] Although preferred embodiments have been described above in detail, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims. [Explanation of symbols]

[0048] 1. Multi-layer structure 10 Support 10a top surface 20 Adhesive layer 30 Resin layer 40 metal layer 50 adhesive layer 60 Glass Layers

Claims

1. A metal support; A pressure-sensitive adhesive layer laminated on the support; A metal layer laminated on the pressure-sensitive adhesive layer; a glass layer laminated on the metal layer; The thickness of the glass layer is 10 μm or more and 300 μm or less.

2. Let a be the length of the support in the longitudinal direction, b be the thickness of the support, and E be the Young's modulus of the support. The stiffness parameter α is expressed as α=E×(a×b ３ 2. The multilayer structure according to claim 1, wherein, when α is 0.1<α<40, α=1.0 / 12.

3. The multi-layer structure according to claim 1 or 2, wherein the material of the support is aluminum, stainless steel, or copper.

4. The multilayer structure according to claim 1 , wherein a resin layer is laminated between the pressure-sensitive adhesive layer and the metal layer.

5. 5. The multi-layer structure according to claim 1, further comprising an adhesive layer laminated between the metal layer and the glass layer.

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