JP2009164029A - Metallic-lustrous decorative film for key pad member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metallic-lustrous laminated film for a key pad member excellent in radio-wave transmitting property and to provide a metallic-lustrous decorative film for the key pad member reduced in environmental load and excellent in recycling property. <P>SOLUTION: The metallic-lustrous decorative film for the key pad member includes the laminated film in which 30 or more A layers 1 of thermoplastic resin layers and 30 or more B layers of thermoplastic resin layers are alternately laminated in a thickness direction. In the laminated film, a relative reflectance is 30-90% in wavelength bands of 400-1,000 nm, tensile stresses in film longitudinal and width directions are 3-90 MPa when extended by 100% in tension test at 150°C and having the number of the layers of 10-220 nm in thickness is larger than the number of layers of 220-320 nm in thickness. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a metallic glossy decorative film used for a top member of a keypad applied to an input unit such as a mobile phone, a PDA, a remote controller, a portable information terminal, an electronic dictionary, and an electronic notebook.

Conventionally, an input keypad usually prints characters / codes on the surface of a film-like substrate, and then forms a hollow convex portion by a molding method such as vacuum forming, pressure forming, press forming, and the like. It is manufactured by filling the recess with acrylic resin or polycarbonate resin by injection molding or the like.
Key top members and keypads are easily worn away by finger rubbing, and even if surface decoration such as painting is peeled off, the ground will come out, so the colored material itself is molded and used as it is It was often used, and there were few variations in texture and appearance design.

  In terms of function, the key of the molded product of resin material / rubber / elastomer is difficult to get dirty with a dense material, but has a problem of slippery due to sebum. Patent Document 1 proposes a keypad using a laminated film of a transparent thermoplastic resin film and a transparent urethane-based resin film in order to prevent scratches even when the surface of the keypad is pressed with a hard object such as a nail. Patent Document 2 provides a keypad for a pushbutton switch having a texture similar to that of a natural material, a texture having a soft touch, and an appearance design.

  On the other hand, mobile phone designs are popular for metallic glossy designs, and there is a strong demand for metallic and glossy casings and keypad exteriors. In order to achieve this metallic design, an inorganic thin film layer is usually formed by vapor-depositing aluminum or the like on the film surface. However, since an inorganic thin film layer such as aluminum is formed on the top cover film, the circuit design tends to be hindered, and the problem of radio interference is also caused. Due to this problem, restrictions on the design are becoming a major issue, such as the installation position of the antenna being restricted.

In response to new requests for design, Patent Documents 3 and 4 relate to keypads for portable communication devices such as mobile phones, and provided high-quality display units. In patent documents 5-7, it can be set as a metallic luster tone, without forming an inorganic thin film layer on a top cover film by making the reflective zone of the film which selectively reflects the light of a specific wavelength into visible light. It became possible. However, the conventional laminated film that selectively reflects light of a specific wavelength has insufficient moldability, such as vacuum forming, vacuum / pressure forming, plug assist vacuum / pressure forming, in-mold forming, insert forming, draw forming, etc. Even if the molding is performed, it is difficult to obtain a desired shape. Moreover, since the part extended | stretched by shaping | molding becomes thin, there also existed a problem that a color change and metal glossiness were impaired. In Patent Document 8, a laminated film for a keypad member excellent in design that gives off an iridescent gloss by selectively reflecting light of a specific wavelength has been realized. It has not been realized.
JP 2000-113758 A JP 2007-141575 A Japanese Patent Application Laid-Open No. 2000-200523 Special table 2001-057125 gazette JP-A-3-041401 JP-A-4-295804 Japanese National Patent Publication No. 9-506837 JP 2006-216493 A

  The present invention provides a laminated film for a key gloss member with a metallic luster tone excellent in radio wave transmission, which is applied to an input unit of a mobile phone, a PDA, a remote controller, a portable information terminal, an electronic dictionary, an electronic notebook, and the like. Let it be an issue. It is another object of the present invention to provide a metallic glossy decorative film for a keypad member that has a small environmental load and is excellent in recyclability because there is no inorganic thin film layer.

  In order to solve the above-described problems, the metallic glossy decorative film film for a keypad member of the present invention is formed by laminating at least 30 layers of A layers made of thermoplastic resin A and B layers made of thermoplastic resin B alternately in the thickness direction. The laminated film has a relative reflectance in the wavelength band of 400 to 1000 nm of 30% or more and 90% or less, and in a tensile test at 150 ° C., the tensile stress at 100% elongation in the film longitudinal direction and the width direction is Each of these is a metallic glossy decorative film for a keypad member comprising a laminated film having a number of layers of 3 to 90 MPa and a layer pair thickness of 10 to 220 nm greater than the number of layers to layer thickness of 220 to 320 nm. It is characterized by being.

The metallic glossy decorative film for keypad members of the present invention has a high brightness and natural metallic glossy design, is excellent in moldability, and maintains a metallic glossy without delamination even after molding. Is.
In addition, the keypad comprising the metallic glossy decorative film for keypad members of the present invention is excellent in recyclability and does not cause electromagnetic interference. Therefore, circuit design can be easily performed.

  Details of the present invention will be described below. In order to achieve the above object, the metallic glossy decorative film for a keypad member according to the present invention comprises alternating layers (A layer) 1 made of resin A and layers (B layer) 2 made of resin B as shown in FIG. Each of which has a structure in which 30 layers or more are laminated, the relative reflectance in the wavelength band of 400 to 1000 nm is 30% or more and 90% or less, and in the tensile test at 150 ° C., the elongation in the film longitudinal direction and the width direction is 100%. It is desirable that the number of layers having a tensile stress of 3 MPa or more and 90 MPa or less and a layer pair thickness of 10 nm or more and less than 220 nm is larger than the number of layers pair layer having a thickness of 220 nm or more and 320 nm or less. Such a film has a high brightness and a natural metallic tone, is excellent in moldability, and maintains a metallic tone without delamination even after molding. Moreover, since the metallic glossy decorative film for a keypad member of the present invention is composed of a polymer, it is a metallic film that transmits electromagnetic waves. Here, the electromagnetic wave means a part of infrared rays and a frequency of 3 Hz to 3 THz.

  As resin in this invention, single-type resin may be sufficient and copolymerization or 2 or more types of blend-type resin may be sufficient. Preferably, it is a thermoplastic resin from the ease of moldability. In each resin, various additives such as antioxidants, antistatic agents, crystal nucleating agents, inorganic particles, organic particles, viscosity reducers, thermal stabilizers, lubricants, infrared absorbers, ultraviolet absorbers, A dopant for adjusting the refractive index may be added.

  Examples of thermoplastic resins include polyolefin resins such as polyethylene, polypropylene, polystyrene, and polymethylpentene, alicyclic polyolefin resins, polyamide resins such as nylon 6 and nylon 66, aramid resins, polyethylene terephthalate, polybutylene terephthalate, and polypropylene terephthalate.・ Polybutyl succinate ・ Polyester resin such as polyethylene-2,6-naphthalate, polycarbonate resin, polyarylate resin, polyacetal resin, polyphenylene sulfide resin, tetrafluoroethylene resin, trifluoroethylene resin, trifluorochloroethylene resin・ Fluorine resin such as ethylene tetrafluoride-6-propylene copolymer / vinylidene fluoride resin, acrylic resin, methacrylic resin, polyacetal resin, It can be used polyglycolic acid resin, polylactic acid resin, and the like. Among these, polyester is particularly preferable from the viewpoint of strength, heat resistance, and transparency.

  The polyester referred to in the present invention refers to a homopolyester or a copolyester that is a polycondensate of a dicarboxylic acid component skeleton and a diol component skeleton. Here, typical examples of the homopolyester include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexanedimethylene terephthalate, and polyethylene diphenylate. In particular, polyethylene terephthalate is preferable because it is inexpensive and can be used in a wide variety of applications.

  The copolyester in the present invention is defined as a polycondensate comprising at least three or more components selected from the following components having a dicarboxylic acid skeleton and components having a diol skeleton. Components having a dicarboxylic acid skeleton include terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid 4,4′-diphenylsulfone dicarboxylic acid, adipic acid, sebacic acid, dimer acid, cyclohexanedicarboxylic acid and ester derivatives thereof. Examples of the component having a glycol skeleton include ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentadiol, diethylene glycol, polyalkylene glycol, and 2,2-bis. (4′-β-hydroxyethoxyphenyl) propane, isosorbate, 1,4-cyclohexanedimethanol, spiroglycol and the like can be mentioned.

  Further, regarding the A layer and the B layer referred to in the present invention, the in-plane average refractive index of the A layer is relatively higher than the in-plane average refractive index of the B layer. The difference between the in-plane average refractive index of the A layer and the in-plane average refractive index of the B layer is preferably 0.03 or more. More preferably, it is 0.05 or more, More preferably, it is 0.1 or more. When the refractive index difference is smaller than 0.03, a sufficient reflectance cannot be obtained, which is not preferable. Further, when the difference between the in-plane average refractive index and the thickness direction refractive index of the A layer is 0.03 or more, and the difference between the in-plane average refractive index and the thickness direction refractive index of the B layer is 0.03 or less, the incident angle Even if becomes larger, the reflectance of the reflection peak does not decrease, which is more preferable.

  As a combination of the thermoplastic resin A and the thermoplastic resin B in the present invention, the absolute value of the difference in SP value between the thermoplastic resin A and the thermoplastic resin B is preferably 1.0 or less. When the absolute value of the difference in SP value is 1.0 or less, delamination hardly occurs. More preferably, it has a layer made of the resin A and a layer made of the resin B containing the same basic skeleton as the resin A. Here, the basic skeleton is a repeating unit constituting the resin. For example, when one resin is polyethylene terephthalate, ethylene terephthalate is the basic skeleton. As another example, when one resin is polyethylene, ethylene is a basic skeleton. When the resin A and the resin B are resins containing the same basic skeleton, peeling between layers is less likely to occur.

  As another combination of the resin A and the resin B, it is preferable that the glass transition temperature difference between the resin A and the resin B is 20 ° C. or less. When the glass transition temperature difference is larger than 20 ° C., the thickness uniformity at the time of forming the laminated film becomes poor and the appearance of metallic luster becomes poor. Also, when a laminated film is formed, problems such as overstretching tend to occur.

  In the metallic glossy decorative film for a keypad member of the present invention, it is preferable that the resin A is polyethylene terephthalate or polyethylene naphthalate, and the resin B is a polyester containing spiroglycol. The polyester comprising spiroglycol refers to a copolyester copolymerized with spiroglycol, a homopolyester, or a polyester blended with them. Polyesters containing spiroglycol are preferred because they have a small glass transition temperature difference from polyethylene terephthalate or polyethylene naphthalate, so that they are not easily stretched at the time of molding and are also difficult to delaminate. More preferably, the resin A is polyethylene terephthalate or polyethylene naphthalate, and the resin B is preferably a polyester comprising spiroglycol and cyclohexanedicarboxylic acid. If the resin B is a polyester comprising spiroglycol and cyclohexanedicarboxylic acid, the difference in the in-plane refractive index from polyethylene terephthalate or polyethylene naphthalate is increased, so that high reflectance is easily obtained. Moreover, since the glass transition temperature difference with polyethylene terephthalate or polyethylene naphthalate is small and the adhesiveness is excellent, it is difficult to be over-stretched at the time of molding and is also difficult to delaminate.

  In the metallic glossy decorative film for a keypad member of the present invention, it is preferable that the resin A is polyethylene terephthalate or polyethylene naphthalate and the resin B is a polyester containing cyclohexanedimethanol. The polyester comprising cyclohexanedimethanol refers to a copolyester obtained by copolymerizing cyclohexanedimethanol, a homopolyester, or a polyester obtained by blending them. Polyesters containing cyclohexanedimethanol are preferred because they have a small glass transition temperature difference from polyethylene terephthalate or polyethylene naphthalate, so that they are unlikely to be overstretched during molding and are also difficult to delaminate. More preferably, the resin B is an ethylene terephthalate polycondensate having a copolymerization amount of cyclohexanedimethanol of 15 mol% to 60 mol%. In this way, while having high reflection performance, the change in optical characteristics due to heating and aging is particularly small, and peeling between layers is less likely to occur. An ethylene terephthalate polycondensate having a copolymerization amount of cyclohexanedimethanol of 15 mol% or more and 60 mol% or less adheres very strongly to polyethylene terephthalate. In addition, the cyclohexanedimethanol group has a cis or trans isomer as a geometric isomer, and a chair type or a boat type as a conformational isomer. In addition, the change in optical characteristics due to thermal history is even less, and blurring during film formation hardly occurs.

  Including the structure in which the A layer and the B layer are alternately stacked in the present invention is defined by the existence of a portion having a structure in which the A layer and the B layer are alternately stacked in the thickness direction. That is, it is preferable that the order of arrangement in the thickness direction of the A layer and the B layer in the film of the present invention is not in a random state, and the order of arrangement of the third layer or more other than the A layer and the B layer is as follows. It is not particularly limited. Moreover, when it has a C layer which consists of A layer, B layer, and resin C, it is more preferable to laminate | stack by regular permutation, such as A (BCA) n, A (BCBA) n, A (BABCBA) n. . Here, n is the number of repeating units. For example, in the case of A (BCA) n where n = 3, this indicates that the layers are stacked in a permutation of ABCABCABCA in the thickness direction.

  In the present invention, a structure in which 30 layers or more of A layers and B layers are alternately laminated in the thickness direction is desirable. More preferably, it is 200 layers or more. Further, the total number of layers of the A layer and the B layer is preferably 600 layers or more. If the A layer and the B layer do not have a structure in which 30 layers or more are alternately stacked in the thickness direction, sufficient reflectance cannot be obtained, and a high-brightness metallic appearance cannot be obtained. Further, when the A layer and the B layer are alternately included in the thickness direction by 200 layers or more, the relative reflectance in the wavelength band of 400 to 1000 nm can be easily set to 40% or more. Moreover, when the total number of layers of the A layer and the B layer is 600 or more, it becomes easy to set the relative reflectance in the wavelength band of 400 to 1000 nm to 60% or more, and it has a metallic appearance with extremely high luminance. It becomes easy. Further, the upper limit value of the number of layers is not particularly limited, but it is 1500 layers or less in consideration of a decrease in wavelength selectivity accompanying a decrease in stacking accuracy due to an increase in the size of the device or an increase in the number of layers. It is preferable.

  In the metallic glossy decorative film for a keypad member of the present invention, it is desirable that the relative reflectance in the wavelength band of 400 to 1000 nm is 30% or more and 90% or less. That is, it is desirable that the relative reflectance is 30% or more and 90% or less at a wavelength of 400 to 1000 nm determined by the relative reflectance measurement method of the present invention. When the relative reflectance in the wavelength band of 400 to 1000 nm is 30% or more, a high-brightness metallic film can be obtained. Further, the metallic tone is maintained even after molding, and the color hardly changes depending on the viewing angle. This is because the relative reflectance is also 30% or more and 90% or less on the higher wavelength side (700 nm or more) than visible light. For example, the film thickness is reduced by stretching, or the reflection band is shifted to the lower wavelength side depending on the viewing angle. Even so, the relative reflectance in the visible light region can be maintained at 30% or more and 90% or less. More preferably, the relative reflectance in the wavelength band of 400 to 1000 nm is 40% or more. Furthermore, the relative reflectance in the wavelength band of 400 to 1000 nm is preferably 80% or more. The higher the relative reflectance, the higher the brightness of the metallic tone. Moreover, it is more preferable that the relative reflectance in the wavelength band of 400 to 1200 nm is 30% or more and 90% or less. In this case, even if the molding is performed at a higher drawing ratio, coloring or the like hardly occurs and the metallic tone can be maintained.

  In the metallic glossy decorative film for a keypad member of the present invention, it is desirable that the average relative reflectance in the wavelength band of 400 to 1000 nm is 30% or more and 90% or less. That is, it is desirable that the average relative reflectance at a wavelength of 400 to 1000 nm determined by the relative reflectance measuring method of the present invention is 30% or more and 90% or less.

  The metallic glossy decorative film for a keypad member of the present invention desirably has a tensile stress of 3 MPa or more and 90 MPa or less at 100% elongation in the film longitudinal direction and width direction in a tensile test at 150 ° C. In such a case, the moldability is excellent, and in any molding such as vacuum molding, vacuum pressure molding, plug assist vacuum pressure molding, in-mold molding, insert molding, cold molding, press molding, drawing molding, etc. It becomes easy to form into a shape. More preferably, in a tensile test at 150 ° C., the tensile stress at 100% elongation in the film longitudinal direction and in the width direction is 3 MPa or more and 50 MPa or less, respectively. In such a case, molding can be performed even with a higher drawing ratio. In the tensile test at 150 ° C., in order for the tensile stress at 100% elongation in the film longitudinal direction and the width direction to be 3 MPa or more and 90 MPa or less, the resin A is a crystalline resin and the resin B is cyclohexane di It is preferably an amorphous resin having a bulky group such as methanol, spiroglycol or neopentylglycol. In such a case, since the resin B is hardly oriented and crystallized even after biaxial stretching, the tensile stress is low. It is also preferred that the time required for forming a laminate comprising the A layer and the B layer at the melting point of each resin to cool and solidify is 3 minutes or more. This is presumed that the tensile stress was lowered because the mixed layer formed at the interface between the A layer and the B layer was thick. Furthermore, it is preferable that the layer thickness is 20 nm or less. When the layer thickness is 20 nm or less, the orientation and crystallization are more difficult to proceed even if the layer is stretched, so that the tensile stress is also reduced.

  In the metallic glossy decorative film for a keypad member of the present invention, the number of layers having a layer pair thickness of 10 nm or more and less than 220 nm is preferably larger than the number of layers having a layer pair thickness of 220 nm or more and 320 nm or less. By doing in this way, it becomes possible to make the metallic tone almost uncolored. Here, the layer pair thickness is a thickness obtained by adding the layer thicknesses of the adjacent A layer and B layer. The layer pair thickness is obtained by adding the layer thicknesses of the mth A layer counted from one surface for only the A layer and the mth B layer counted from the same surface for only the B layer. Here, m represents an integer. For example, when A1 layer / B1 layer / A2 layer / B2 layer / A3 layer / B3 layer ... are arranged in order from one surface to the opposite surface, the A1 layer and the B1 layer are the first layer. The A2 layer and the B2 layer are the second layer pair, and the A3 layer and the B3 layer are the third layer pair. When the number of layers having a layer pair thickness of 10 nm or more and less than 220 nm is the same as or less than the number of layers having a layer thickness of 220 nm or more and 320 nm or less, the reflectance decreases toward the lower wavelength side in the reflection band of the wavelength band 400 to 1100 nm. Since it has a tasteful appearance, it is not preferable. This occurs because the density of the layer pair that causes reflection on the low wavelength side is reduced. Therefore, as an order of the layer pair thickness of the layers constituting the laminated film, the layer pair thickness does not increase or decrease monotonically in a monotonic sequence, but the layer pair thickness in a geometric sequence while satisfying the above conditions. It is preferable to increase or decrease. More preferably, the number of layers having a layer pair thickness of 120 nm to 220 nm is preferably 1.05 to 2.5 times the number of layers having a layer pair thickness of 220 nm to 320 nm. In this case, it is possible to obtain a metallic tone without any coloration.

  Since the metallic glossy decorative film for keypad member of the present invention displays the character / symbol display portion by transmitting the backlight, it also requires transmittance from the functional side. In order to achieve the above object, it is desirable that the average transmittance in the wavelength band of 400 to 1000 nm is 10% or more and 70% or less. Unless the average transmittance in the wavelength band 400 to 1000 nm is 10% or more and 70% or less, the light of the backlight is absorbed and sufficient brightness cannot be obtained. End up. In particular, mobile phones are frequently used at night or in the dark. In such a case, the visibility of the character / symbol display section is important. More preferably, the transmittance in the wavelength band of 400 to 1000 nm is 10% or more and 55% or less. In such a case, it becomes a more preferable form in which the visibility of the character / symbol display portion is not problematic while the metallic luster-like design is the best.

  In the metallic glossy decorative film for a keypad member of the present invention, the intrinsic viscosity of the A layer corresponding to the film surface layer is preferably 0.50 to 0.80 dl / g. More preferably, the intrinsic viscosity of the A layer corresponding to the film surface layer is 0.55 to 0.75 dl / g. More preferably, the intrinsic viscosity of the A layer corresponding to the film surface layer portion is 0.60 to 0.70. In such a case, the moldability is excellent, and in any molding such as vacuum molding, vacuum pressure molding, plug assist vacuum pressure molding, in-mold molding, insert molding, cold molding, press molding, drawing molding, etc. It becomes easy to form into a shape. In addition, the keypad must be made of a material that can withstand repeated hitting with the belly and nails of the finger and has excellent wear resistance. Also from such a viewpoint, it is preferable that the intrinsic viscosity of the A layer corresponding to the film surface layer portion is 0.60 to 0.70. In such a case, it is possible to obtain a metallic glossy decorative film for a keypad member having excellent wear resistance required as a top surface member of the keypad.

  In the metallic glossy decorative film for a keypad member of the present invention, it is preferable that the relative reflectance in the wavelength band of 400 to 700 nm is 30% or more at a stretched portion of 1.2 to 2 times. When the relative reflectance in the wavelength band of 400 to 700 nm in the stretched portion of 1.2 times or more and 2 times or less is 30% or more, the metallic tone can be maintained without being colored even after molding.

  Furthermore, the metallic glossy decorative film for keypad members of the present invention preferably has a layer mainly composed of polyethylene terephthalate or polyethylene naphthalate of 3 μm or more on at least one side. More preferably, it has a layer mainly composed of polyethylene terephthalate or polyethylene naphthalate of 5 μm or more. Further, it is more preferable to have a layer mainly composed of polyethylene terephthalate or polyethylene naphthalate of 3 μm or more on both sides. If there is no layer made of polyethylene terephthalate or polyethylene naphthalate having a size of 3 μm or more, it is not preferable because the scratches are very visible when the surface is scratched.

  The keypad using the present invention preferably includes the metallic glossy decorative film for the keypad member. In addition to the metallic glossy decorative film for a keypad member of the present invention, it may comprise any of a hard coat layer, an embossed layer, a weather resistant layer (UV cut layer), a colored layer, an adhesive layer, a base resin layer, etc. preferable. Such a keypad can be made of an all-polymer and does not contain metal or heavy metal, and therefore has a low environmental load, excellent recyclability, and does not cause electromagnetic interference. In existing technologies, inorganic thin film layers such as aluminum are deposited, but if these existing technologies are used in electronic devices that require transmission and reception of radio waves, such as mobile phones, the functions that are originally required are impaired. there is a possibility. Applying the appearance design leads to a result of impairing the function that is originally required. Therefore, in the metallic glossy decorative film for a keypad member of the present invention, it is desirable that the attenuation factor at 800 MHz is 2.0 dB or less from the viewpoint of not impairing the original function of an electronic device such as a mobile phone. More preferably, the attenuation rate at 800 MHz is 1.0 dB or less. In such a case, even if the metallic glossy decorative film for a keypad member of the present invention is used, it can be a keypad top surface member that does not impair the original function.

  The keypad using the present invention preferably has a colored layer. In the metallic glossy decorative film for a keypad member of the present invention, a part of visible light may be transmitted. Therefore, the color of the keypad can be adjusted by providing a colored layer. In the metallic glossy decorative film for a keypad member of the present invention, the character / symbol display portion is displayed by the transmitted light of the backlight. For this purpose, it is preferable to have a colored layer that transmits light on the character / symbol display portion, and a colored layer that blocks light other than the backlight layer and blocks the light on the portion where the surface is desired to have a metallic luster. Printing is preferably used for the colored layer.

  The metallic glossy decorative film for a keypad member of the present invention can be subjected to hairline processing on the upper surface or the lower surface, and the design can be improved. Hairline processing is a surface processing technique for applying a myriad of fine lines such as hair, and for example, patterns on various lines can be applied to the surface of the film by a method such as a wire brush method or a sand roll paper method. Either method may be used for the metallic glossy decorative film for a keypad member of the present invention, and there is no particular limitation. Moreover, the direction which performs a hairline process may be any of the longitudinal direction of the metal glossy decoration film for keypad members of this invention, and the width direction.

  Next, the preferable manufacturing method of the laminated | multilayer film of this invention is demonstrated below. Resin A pellets and resin B pellets dried in hot air or under vacuum are prepared and supplied to separate extruders. In the extruder, the resin melted by heating to a temperature equal to or higher than the melting point is made uniform in the amount of resin extruded by a gear pump or the like, and foreign matter or denatured resin is removed through a filter or the like.

The resin compositions A and B sent out from different flow paths using these two or more extruders are then fed into the multilayer laminating apparatus. As the multilayer laminating apparatus, a multi-manifold die, a feed block, a static mixer, or the like can be used. Moreover, you may combine these arbitrarily. The number of layers having a layer pair thickness of 10 nm or more and less than 220 nm is included, wherein the number of layers having a layer pair thickness of 10 nm or more and less than 220 nm is included. In order to achieve more than the number of layers, it is preferable to use a feed block having at least one member having a large number of fine slits. Furthermore, in order to efficiently obtain the effects of the present invention, it is preferable to use a feed block including at least two members having a large number of fine slits separately. When such a feed block is used, since the apparatus does not become extremely large, there is little foreign matter due to thermal degradation, and high-precision lamination is possible even when the number of laminations is extremely large. Also, the stacking accuracy in the width direction is significantly improved as compared with the prior art. It is also possible to form an arbitrary layer thickness configuration. For this reason, it becomes easy to achieve the following structure which is a preferable aspect of this invention.
a) The total number of layers of the layer made of resin A (A layer) and the layer made of resin B (B layer) is 600 layers or more.
b) The relative reflectance in the wavelength band of 400 nm to 1000 nm is 80% or more and 90% or less.
c) The number of layers having a layer pair thickness of 120 to 220 nm is 1.05 to 2.5 times the number of layers having a layer thickness of 220 to 320 nm.
d) At least one side has a layer mainly composed of polyethylene terephthalate or polyethylene naphthalate of 3 μm or more.

  As the shape of the slit, it is preferable that the slit area on the side where the resin is introduced is not the same as the slit area on the side where the resin is not introduced. With such a structure, the flow rate distribution on the side where the resin is introduced and the side where the resin is not introduced can be reduced, so that the laminating accuracy in the width direction is improved. Further, (slit area on the side where no resin is introduced) / (slit area on the side where the resin is introduced) is preferably 0.2 or more and 0.9 or less. More preferably, it is 0.5 or less. Moreover, it is preferable that the pressure loss in a feed block will be 1 Mpa or more. The slit length is preferably 20 mm or more. On the other hand, the thickness of each layer can be controlled by adjusting the gap and length of the slit.

It is also preferable to have a manifold corresponding to each slit. The manifold makes the flow velocity distribution in the width direction inside the slit uniform, so the lamination ratio in the width direction of the laminated films can be made uniform, and even a large area film can be laminated accurately, The reflectance of the reflection peak can be controlled with high accuracy.
More preferably, the resin is supplied from one liquid reservoir to two or more slit members. In this way, even if there is a slight flow distribution in the width direction inside the slit, it is further laminated by the confluence apparatus described below, so the total lamination ratio is uniform, It becomes possible to reduce unevenness of the next reflection band.

  In this apparatus, since the thickness of each layer can be adjusted by the shape (length, width) of the slit, any layer thickness can be achieved. On the other hand, in the conventional apparatus, in order to achieve lamination of 300 layers or more, it is common to use a square mixer together. However, in such a method, the lamination flow is deformed and laminated in a similar shape. In addition, it has been difficult to achieve an arbitrary layer thickness. For this reason, it is impossible to accurately and efficiently form a layer structure in which the number of layers having a thickness of 10 nm to 220 nm, which is a feature of the present invention, is larger than the number of layers having a thickness of 220 nm to 320 nm. Met.

Next, in order to set the relative reflectance in the wavelength band of 400 nm to 1000 nm, which is a feature of the present invention, to 30% or more and 90% or less, the layer thickness of each layer is set to at least the wavelength band of 400 nm to 1000 nm based on the following formula 1. It must be designed so that reflection occurs. Further, it preferably includes at least a layer structure in which the layer pair thickness gradually increases from 120 nm to 320 nm as the thickness increases from one surface to the opposite surface. The reflectance is controlled by the difference in refractive index between the A layer and the B layer and the number of layers of the A layer and the B layer.
2 × (na · da + nb · db) = λ Equation 1
na: In-plane average refractive index of the A layer nb: In-plane average refractive index of the B layer da: Layer thickness (nm) of the A layer
db: Layer thickness of layer B (nm)
λ: main reflection wavelength (primary reflection wavelength)
Further, in the present invention, the number of layers having a layer pair thickness of 10 nm or more and less than 220 nm must be larger than the number of layers having a layer pair thickness of 220 nm or more and 320 nm or less. Rather than increasing or decreasing in a linear function with respect to the layer pair order, the layer pair thickness change at less than 220 nm is more gradual than the layer pair thickness change at 220 nm to 320 nm. preferable.

  The molten laminate formed in the desired layer configuration in this way is then formed into a desired shape by a die and then discharged. And the sheet | seat laminated | stacked in the multilayer discharged | emitted from die | dye is extruded on cooling bodies, such as a casting drum, and is cooled and solidified, and a casting film is obtained. At this time, it is preferable to use a wire-like, tape-like, needle-like, or knife-like electrode to be brought into close contact with a cooling body such as a casting drum by an electrostatic force and rapidly solidify. Also preferred is a method in which air is blown out from a slit-like, spot-like, or planar device to be brought into close contact with a cooling body such as a casting drum and rapidly cooled and solidified, or brought into close contact with a cooling body with a nip roll and rapidly solidified.

  The casting film thus obtained is preferably biaxially stretched as necessary. Biaxial stretching refers to stretching in the longitudinal direction and the width direction. Stretching may be performed sequentially in two directions or simultaneously in two directions. Further, re-stretching may be performed in the longitudinal direction and / or the width direction. In particular, in the present invention, it is preferable to use simultaneous biaxial stretching from the viewpoint of suppressing in-plane orientation difference and suppressing surface scratches.

  First, the case of sequential biaxial stretching will be described. Here, stretching in the longitudinal direction refers to stretching for imparting molecular orientation in the longitudinal direction to the film, and is usually performed by a difference in peripheral speed of the roll, and this stretching may be performed in one step. Alternatively, a plurality of roll pairs may be used in multiple stages. Although it changes with kinds of resin as a magnification of extending | stretching, 2 to 15 times is preferable normally, and when polyethylene terephthalate is used for either of the resin which comprises a laminated | multilayer film, 2 to 7 times are used especially preferably. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +100 degreeC of resin which comprises a laminated | multilayer film are preferable.

  The uniaxially stretched film thus obtained is subjected to surface treatment such as corona treatment, flame treatment and plasma treatment as necessary, and then functions such as slipperiness, easy adhesion and antistatic properties are provided. It may be applied by in-line coating.

  The stretching in the width direction refers to stretching for giving the film an orientation in the width direction. Usually, the tenter is used to convey the film while holding both ends of the film with clips, and the film is stretched in the width direction. Although it changes with kinds of resin as a magnification of extending | stretching, 2 to 15 times is preferable normally, and when polyethylene terephthalate is used for either of the resin which comprises a laminated | multilayer film, 2 to 7 times are used especially preferably. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +120 degreeC of resin which comprises a laminated | multilayer film are preferable.

  The biaxially stretched film is preferably subjected to a heat treatment at a temperature not lower than the stretching temperature and not higher than the melting point in the tenter in order to impart flatness and dimensional stability. After being heat-treated in this way, it is gradually cooled down uniformly, then cooled to room temperature and wound up. Moreover, you may use a relaxation process etc. together in the case of annealing from heat processing as needed.

  Next, the case of simultaneous biaxial stretching will be described. In the case of simultaneous biaxial stretching, the obtained cast film is subjected to surface treatment such as corona treatment, flame treatment, plasma treatment, etc. The function may be imparted by in-line coating.

  Next, the cast film is guided to a simultaneous biaxial tenter, and conveyed while holding both ends of the film with clips, and stretched in the longitudinal direction and the width direction simultaneously and / or stepwise. As simultaneous biaxial stretching machines, there are pantograph method, screw method, drive motor method, linear motor method, but it is possible to change the stretching ratio arbitrarily and drive motor method that can perform relaxation treatment at any place or A linear motor system is preferred. Although the stretching magnification varies depending on the type of resin, it is usually preferably 6 to 50 times as the area magnification. When polyethylene terephthalate is used as one of the resins constituting the laminated film, the area magnification is 8 to 30 times. Is particularly preferably used. In particular, in the case of simultaneous biaxial stretching, it is preferable to make the stretching ratios in the longitudinal direction and the width direction the same and to make the stretching speeds substantially equal in order to suppress the in-plane orientation difference. Moreover, as extending | stretching temperature, the glass transition temperature-glass transition temperature +120 degreeC of resin which comprises a laminated | multilayer film are preferable.

  The film thus biaxially stretched is preferably subsequently subjected to a heat treatment not less than the stretching temperature and not more than the melting point in the tenter in order to impart flatness and dimensional stability. In order to suppress the distribution of the main alignment axis in the width direction during this heat treatment, it is preferable to perform a relaxation treatment in the longitudinal direction immediately before and / or immediately after entering the heat treatment zone. After being heat-treated in this way, it is gradually cooled down uniformly, then cooled to room temperature and wound up. Moreover, you may perform a relaxation | loosening process in a longitudinal direction and / or the width direction at the time of annealing from heat processing as needed. Immediately before and / or immediately after entering the heat treatment zone, a relaxation treatment is performed in the longitudinal direction.

An evaluation method of physical property values used in the present invention will be described.
(Method for evaluating physical properties)
(1) Relative reflectance A spectrophotometer (U-3410 Spectrophotometer) manufactured by Hitachi Ltd. was fitted with a φ60 integrating sphere 130-0632 (Hitachi Ltd.) and a 10 ° inclined spacer, and the reflectance was measured. The band parameter is set to 2 / servo, the gain is set to 3, and the range from 187 to 2600 nm is set to 120 nm / min. Measured at a detection speed of. In order to standardize the reflectance, an attached Al ₂ O ₃ plate was used as a standard reflecting plate. The reflectance of the integer wavelength was determined in the target wavelength range. Moreover, the average value of the obtained reflectance in the target wavelength range was defined as the average relative reflectance.

(2) Intrinsic viscosity Calculated from the solution viscosity measured at 25 ° C in orthochlorophenol. The solution viscosity was measured using an Ostwald viscometer. The unit is [dl / g]. The n number was 3, and the average value was adopted.

(3) Number of layers, layer pair thickness Using a scanner (CanonScanD123U manufactured by Canon, Inc.), a cross-sectional image of a film obtained with a transmission electron microscope is used to capture an image with an image size of 720 dpi. Saved as a map file (BMP). Next, the image processing software Image-Pro Plus ver. 4 (manufactured by Media Cybernetics) was used to open the BMP file and perform image analysis. The typical image processing conditions are described below. First, after processing with a low-pass filter (size 7 × 7 strength 10 times 10), numerical data of position and brightness was obtained in the vertical thick profile mode. The position was previously scaled by spatial calibration. This position and luminance data were subjected to sampling step 6 (thinning 6) and three-point moving average processing on Microsoft Excel CEL2000. Further, the obtained luminance was differentiated by position, and the maximum value and the minimum value of the differential curve were calculated. Then, the distance between the positions where the adjacent maximum value-maximum value or the adjacent minimum value-minimum value is set as the layer pair thickness, and all the layer pair thicknesses were calculated. In this case, a constant threshold is set for the differential value so as not to detect the noise of the differential curve, and the distance between adjacent maximum values-maximum values or adjacent minimum values-minimum values corresponding to the layer pair thickness. Processed to detect distance.

(4) Transmittance A spectrophotometer (U-3410 Spectrophotometer) manufactured by Hitachi, Ltd. was attached with an attached parallel light cell and the transmittance was measured. The band parameter is set to 2 / servo, the gain is set to 3, and the range from 187 to 2600 nm is set to 120 nm / min. Measured at a detection speed of.

(5) Appearance Judging by visual inspection, ◎ if it is a metallic tone without coloring, ○ if it is a metallic tone that is slightly colored, × if it is colored or colored depending on the angle × It was.
(6) Glossiness According to the method defined in JIS-K7105 (1981), specular glossiness of 60 degrees was measured using a digital variable angle glossiness meter UGV-5D manufactured by Suga Test Instruments. In addition, since glossiness was too high, in the measurement, a filter that was all dimmed to 1/10 was inserted and measured.
(7) Formability It tested using the vacuum forming apparatus SANWA KOGYO PLAVAC TYPE FB-7. A columnar cup having a depth of 15 mm and a diameter of 50 mm was pressed against the sample heated to 200 ° C., and the air in the cup was taken out instantaneously to make a vacuum. At this time, if the sample was deformed following the shape of the cup, it was judged that the moldability was high, and marked と し た. Moreover, although the sample was deformed following the cup, a sample where the corner portion was not sufficiently formed was rated as “◯”. Further, samples that did not follow the cup and hardly deformed were judged to have low moldability and were evaluated as x.
(8) Electromagnetic wave shielding property The electromagnetic wave shielding property was measured by KEC method of Kansai Electronics Industry Promotion Center. The measurement conditions are as follows.
Measuring device signal generator: Anritsu MG3601A
Spectrum analyzer: Anritsu MS2601A
Preamplifier: Anritsu MH648A
Measurement method --- KEC method (near electric field, near magnetic field)
Measurement frequency --- 0.1 to 1GHz
Sample size --- 150mm × 150mm
Spacer --- Steel Wool (“Bonster”)
Sample measurement: Measurement was performed three times for one sample, and the average value was adopted.
About the evaluation result, the electric field shielding property in 800 MHz was represented by the attenuation factor (dB).

(9) Character visibility The backlight is transmitted in a dark place where light does not enter and is visually determined. ◎ when the character / symbol display is clearly recognizable, ◯ when the character / symbol display is clearly recognizable but with insufficient backlight transmission, and character with or without backlight transmission X was marked when x was not clearly recognized.

Example 1
1. 100 parts by weight of synthetic dimethyl terephthalate of polyester 1, 17.4 parts by weight of dimethyl 1,4-cyclohexanedicarboxylate having a cis / trans ratio of 72/28, 64 parts by weight of ethylene glycol, and 20 parts by weight of spiro glycol Then, 0.04 part by weight of manganese acetate tetrahydrate and 0.02 part by weight of antimony trioxide were weighed and charged into a transesterification reactor. The contents were dissolved at 150 ° C. and stirred. Subsequently, methanol was distilled while slowly raising the temperature of the reaction contents to 235 ° C. while stirring. After distillation of a predetermined amount of methanol, an ethylene glycol solution containing 0.02 part by weight of trimethyl phosphoric acid was added. After adding trimethyl phosphoric acid, the mixture was stirred for 10 minutes to complete the transesterification reaction. Thereafter, the transesterification reaction product was transferred to a polymerization apparatus.

Next, the content of the polymerization apparatus was stirred and the pressure was reduced and the temperature was raised, and polymerization was carried out while distilling ethylene glycol. The reduced pressure was reduced from normal pressure to 133 Pa or less over 90 minutes, and the temperature was raised from 235 ° C. to 285 ° C. over 90 minutes. When the stirring torque of the polymerization apparatus reached a predetermined value, the inside of the polymerization apparatus was returned to normal pressure with nitrogen gas, the valve at the bottom of the polymerization apparatus was opened, and a gut-shaped polymer was discharged into the water tank. The polyester gut cooled in the water tank was cut with a cutter to form a chip to obtain crystalline polyester 1 (polyethylene terephthalate).
The obtained polyester 1 had an intrinsic viscosity of 0.65 and a Tg of 80 ° C.

2. Similarly to the synthesis of polyester 2, polyester 2 was polymerized in the same manner as described above except that 67.6 parts by weight of dimethyl terephthalate and 54 parts by weight of ethylene glycol were used. The obtained polyester 2 had an intrinsic viscosity of 0.72. The dicarboxylic acid component of this polyester 2 was 80 mol% terephthalic acid and 20 mol% cyclohexanedicarboxylic acid. The diol component of polyester 1 was 85 mol% ethylene glycol and 15 mol% spiroglycol. Polyester 2 was amorphous.

  Next, synthesized polyester 1 (PET) and polyester 2 (PE / SPG · T / CHDC) were prepared as two types of thermoplastic resins constituting the metallic glossy decorative film for a keypad member of the present invention. Polyester 1 (PET) 91.46 wt%, agglomerated silica particles with an average secondary particle size of 1 μm are 0.04 wt%, a malonic ester-based UV absorber (“Sun Dubore B-CAP” manufactured by Clariant Japan) Of 8.5 wt% was used as Resin A. Next, polyester B (PE / SPG · T / CHDC) alone was used as resin B. These resins A and B were each dried and then fed to separate extruders.

Resins A and B were each melted at 280 ° C. by an extruder, passed through a gear pump and a filter, and then joined by a 801-layer feed block. The laminating apparatus in the 801-layer feed block was composed of three slit members having 267 slits. In the feed block, the merged resins A and B are changed so that the thickness of each layer gradually increases from the surface side toward the opposite surface side, and the thickness direction in which the resin A is 401 layers and the resin B is 400 layers. It was set as the structure laminated | stacked alternately. The slit shape was designed so that both surface layer portions were made of resin A, and the layer thicknesses of the adjacent A layer and B layer were substantially the same. In this design, a reflection band exists at 400 to 1200 nm. The thus obtained laminate comprising 801 layers is supplied to a multi-manifold die, and further, a layer made of resin A supplied from another extruder is formed on the surface layer, and after forming into a sheet shape, Rapid solidification was effected on a casting drum maintained at a surface temperature of 25 ° C. by application of electricity. The flow path shape and the total discharge amount were set so that the time from when the resin A and the resin B were merged in the laminating apparatus until the resin A and the resin B were rapidly cooled and solidified on the casting drum was about 8 minutes.
The obtained cast film was heated with a roll group set at 75 ° C., and then stretched 3.0 times in the longitudinal direction while rapidly heating from both sides of the film with a radiation heater between 100 mm in the stretch section length. Cooled down. Subsequently, both sides of this uniaxially stretched film were subjected to corona discharge treatment in air, the wetting tension of the base film was set to 55 mN / m, and the treated surface (polyester resin having a glass transition temperature of 18 ° C.) / (Glass transition) Polyester resin having a temperature of 82 ° C.) / Laminate-forming film coating liquid composed of silica particles having an average particle diameter of 100 nm was applied to form a transparent, easy-sliding, and easy-adhesion layer.

  This uniaxially stretched film was guided to a tenter, preheated with hot air at 100 ° C., and stretched 3.3 times in the transverse direction at a temperature of 110 ° C. The stretched film was directly heat-treated in a tenter with hot air of 240 ° C., then subjected to a relaxation treatment of 8% in the width direction at the same temperature, and then gradually cooled to room temperature and wound up. The thickness of the obtained film was 100 μm. The metal glossy decorative film for keypad member obtained here is set to 3. The obtained results are shown in the film properties of Table 1.

A keypad was then created using 1.
A printing layer 4 for displaying characters and symbols was printed on the lower surface of 3. At this time, a black print layer that does not transmit light is provided in a portion that shows a metallic glossy tone, and a blue print layer is provided in a display portion of characters and symbols that transmits backlight light.
3 to which the printed layer 4 was applied was inserted into a predetermined position in a mold for forming a key top having a quadrangular prism shape. Subsequently, the polycarbonate resin 5 was injected into the mold, thereby obtaining a keypad having 3 coated with the printing layer 4 on the upper surface and each side surface of the resin molded body. A part of the cross section of the obtained keypad is shown in FIG. The obtained results are shown in the keypad characteristics of Table 1.

(Example 2)
Instead of the resin B in Example 1, polyethylene terephthalate (PE / CHDM • PET) [PETG6763 manufactured by Eastman] obtained by copolymerizing 30 mol% of cyclohexanedimethanol with ethylene glycol was used. Polyethylene terephthalate (PE / CHDM · T) obtained by copolymerizing 30 mol% of cyclohexanedimethanol with ethylene glycol was an amorphous resin. Other conditions and devices were the same as in Example 1. The obtained results are shown in the film properties of Table 1. Next, a keypad was prepared using the metallic glossy decorative film for keypad member obtained here. Other conditions and devices were the same as in Example 1. The thickness of the obtained film was 100 μm. The obtained results are shown in the keypad characteristics of Table 1.

(Example 3)
In Example 2, the same conditions and apparatus were used except that the feed block was changed. The feed block used was a 201-layer feed block consisting of one slit member having 201 slits. The merged resins A and B are changed so that the thickness of each layer is gradually increased from the surface side to the opposite surface side in the feed block. The thickness direction is composed of 101 layers of resin A and 100 layers of resin B. It was set as the structure laminated | stacked alternately. Here, the shape of each fine slit in the feed block was adjusted so that the layer pair thickness on the thin side was relatively increased as in Example 1. Moreover, the slit shape was designed so that both surface layer parts might be resin A, and the layer thickness of the adjacent A layer and B layer might become substantially the same. The thickness of the obtained film was 25 μm. The obtained results are shown in the film properties of Table 1. Next, a keypad was prepared using the metallic glossy decorative film for keypad member obtained here. Other conditions and devices were the same as in Example 1. The obtained results are shown in the keypad characteristics of Table 1.
Example 4
The metallic glossy decorative film for keypad member obtained in Example 1 was subjected to hairline processing by a sand roll paper method. The obtained results are shown in the film properties of Table 1.
Next, a keypad was prepared using the metallic glossy decorative film for keypad member obtained here. At this time, the hairline processing direction was set to be the longitudinal direction of the film. Other conditions and devices were the same as in Example 1. The obtained results are shown in the keypad characteristics of Table 1.

(Comparative Example 1)
A BO-PET film was made from the resin A in Example 1, and aluminum was evaporated on one side. The thickness of the obtained film was 25 μm. The obtained results are shown in the film properties of Table 1. Next, the keypad was created using the vapor deposition film obtained here. The display unit for displaying characters / symbols was obtained by peeling off aluminum deposited in the shape of characters / symbols with a laser. A blue printing layer that transmits backlight is provided on the lower surface. Other conditions and devices were the same as in Example 1. The obtained results are shown in the keypad characteristics of Table 1.

(Comparative Example 2)
In Example 3, the flow path shape and the total discharge amount were set so that the time from when the resin A and the resin B merged in the laminating apparatus to when the resin A and the resin B were rapidly cooled and solidified on the casting drum was about 1 minute. The longitudinal draw ratio was 3.6 times, and the transverse draw ratio was 3.9 times. Other conditions and devices were the same as in Example 7. The thickness of the obtained film was 25 μm. The obtained results are shown in the film properties of Table 1. Next, a keypad was prepared using the metallic glossy decorative film for keypad member obtained here. Other conditions and devices were the same as in Example 1. The obtained results are shown in the keypad characteristics of Table 1.

(Comparative Example 3)
In Example 1, the same conditions and apparatus were used except that the feed block was changed. The feed block used was a 57-layer feed block consisting of one slit member having 57 slits. In the feed block, the merged resins A and B are changed so that the thickness of each layer gradually increases from the surface side to the opposite surface side, and the thickness direction is composed of 29 layers of resin A and 28 layers of resin B. It was set as the structure laminated | stacked alternately. Here, the shape of each fine slit in the feed block was adjusted so that the layer pair thickness on the thin side was relatively increased as in Example 1. Moreover, the slit shape was designed so that both surface layer parts might be resin A, and the layer thickness of the adjacent A layer and B layer might become substantially the same. The thickness of the obtained film was 8 μm. The obtained results are shown in the film properties of Table 1. Since this laminated film could not satisfy claim 1 in both the reflection band and the reflectance, and the appearance was not a metallic glossy tone but a transparent film, and the metallic glossy tone conditions were not satisfied, this laminated film was used. No keypad was created.

The present invention relates to a metallic glossy decorative film for a keypad member in which layers made of at least two kinds of resins are laminated. More specifically, the present invention relates to a laminated film suitable as a metallic glossy decorative film for a mobile phone keypad member.

The figure which shows the laminated structure of this invention Figure showing part of the cross section of the keypad

Explanation of symbols

1 Layer made of resin A (A layer)
2 Layer made of resin B (B layer)
3 Metallic glossy decorative film for keypad member of the present invention 4 Print layer 5 Polycarbonate resin

Claims (6)

A top surface member of a keypad, which is a laminated film in which an A layer made of thermoplastic resin A and a B layer made of thermoplastic resin B are alternately laminated in the thickness direction, each having a wavelength band of 400 to The relative reflectance at 1000 nm is 30% or more and 90% or less, and in the tensile test at 150 ° C., the tensile stress at 100% elongation in the film longitudinal direction and the width direction is 3 MPa or more and 90 MPa or less, respectively, A metallic glossy decorative film for a keypad member comprising a laminated film in which the number of layers having a layer pair thickness of 10 nm or more and less than 220 nm is larger than the number of layers having a layer pair thickness of 220 nm or more and 320 nm or less. 2. The metallic glossy decorative film for keypad members according to claim 1, wherein the A layer corresponding to the surface layer portion of the film is a laminated film formed of polyester having an intrinsic viscosity of 0.50 to 0.80 dl / g. 3. The metallic glossy decorative film for keypad members according to claim 1, wherein an average relative reflectance in a wavelength band of 400 to 1000 nm is 30% or more and 90% or less. The metallic glossy decorative film for a keypad member according to any one of claims 1 to 3, wherein a hairline appearance process is applied. The metallic glossy decorative film for a keypad member according to any one of claims 1 to 4, wherein an attenuation factor at 800 MHz is 2.0 dB or less. A metallic glossy decorative film for a keypad member used for a mobile phone comprising the laminated film according to claim 1.

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