JP2002222035A - Key mat member and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key mat member which is durable to long-period use and has a superior keying characteristic function. SOLUTION: A decoration sheet 2 having a pattern layer on at least one surface of a base material sheet with superior rigidity is so molded in three dimensions as to project at respective specific positions toward the base material sheet 4 and then form key button parts 5 and moldings 3 for maintaining a button shape which are made of hard resin are adhered integrally in recessed parts 6 of the decoration sheet 2 on the opposite side from the key button parts 5, thus the key mat member is formed. This mat member is backed and reinforced with a rubber elastic layer 11 at a position which is always stressed when used for a long period, i.e., nearby the peripheral edges of the key button parts 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key mat member for use in mobile phones, home electric appliances and the like, in which a plurality of key buttons are integrally arranged.

[0002]

2. Description of the Related Art Conventionally, as a key mat member 1 (see FIG. 9), a decorative sheet 2 having at least a design layer provided on one surface of a base sheet 4 having excellent rigidity such as a polycarbonate film is formed by vacuum molding or the like. The three-dimensional molding is performed such that the key button part 5 is formed by projecting the predetermined position to the base sheet 4 side at each position, and the three-dimensionally formed decorative sheet 2 is set in a mold for injection molding, and the mold is closed. Then, a molding resin such as a hard resin is formed in the cavity, and the molding resin is cooled and solidified, so that the molded product 3 for maintaining the button shape is integrated into the concave portion 6 existing on the back side of the key button portion of the decorative sheet 2. Some were obtained by bonding.

In the above-mentioned key mat member 1, a film having excellent rigidity is used as the base sheet 4 in order to prevent the key button portion 5 from being damaged by an input using a nail or a writing instrument, This is to protect the design layer (the light-shielding colored layer 8 and the light-transmitting colored layer 9 in FIG. 9) from the stress due to the input of the input and the grease of the hand.

[0004] Further, the provision of the button-shaped maintaining product 3 made of a hard resin or the like in the concave portion 6 existing on the back side of the key button portion 5 of the decorative sheet 2 is based on the key button protruding from the surface of the decorative sheet 2. This is to prevent the unit 5 from being crushed when a key is pressed. The molded product 3 for maintaining the button shape usually has a bar-shaped portion that is elongated and extends downward, and performs a contact function of pushing the metal dome 7.

[0005]

However, according to the prior art, when a pattern is formed on the base sheet 4 by printing as described above, the bending operation and the solvent of the printing solvent are repeated during a long-term use. Since the mechanical properties of the base sheet 4 are deteriorated by the action, there is a problem that a crack 10 is generated on the periphery of the key button portion 5 of the decorative sheet 2 (see FIG. 10).

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a key mat member having an excellent keying characteristic function that can withstand long-term use.

[0007]

In order to achieve the above object, the present invention provides a decorative sheet having at least a design layer provided on one surface of a base sheet having excellent rigidity. A key mat that is three-dimensionally formed so as to protrude to the side to form a key button portion, and a molded product for maintaining a button shape made of a hard resin is integrally bonded in a recess present on the back side of the key button portion of the decorative sheet. The member was configured such that the periphery of the key button portion was reinforced and backed with a rubber elastic layer.

In the above structure, the rubber elastic layer is formed of a molded resin layer, and is positioned so as to straddle the outer peripheral portion of the concave portion and the back surface of the molded product for maintaining the button shape.

In the above structure, the rubber elastic layer is formed of a printing layer, and is positioned on the surface of the base sheet on the design layer side so as to straddle the outer peripheral portion and the inner peripheral portion of the concave portion. I let it.

[0010] Further, the present invention provides a decorative sheet having at least a design layer provided on one surface of a base sheet having excellent rigidity.
Perform three-dimensional molding using a three-dimensional molding die so as to form a key button part protruding toward the base material sheet for each predetermined position, and then place this between injection molding dies and clamp the mold. A cavity is formed between a concave portion present on the back side of the key button portion of the decorative sheet and a mold having a gate portion, and a molten molding resin made of a hard resin is injected into the cavity to enter the concave portion. In a method for obtaining a key mat member by integrally forming and bonding the button-shape-maintaining molded article simultaneously with the molding, the mold is opened after the button-shape-maintaining molded article is molded, and then the button-shape maintaining molded article is integrally bonded. The decorative sheet and the gate, in which the decorated sheet is placed between different molds, or the mold having the gate portion is replaced with another mold, and the molded article for button shape maintenance is integrally bonded by mold clamping and the gate Another with the part Forming a cavity positioned so as to straddle the outer peripheral portion of the concave portion and the back surface of the button shape maintaining molded product between the mold and the mold, and inject a molten molding resin made of a rubber elastic material into the cavity. Thereby, the rubber elastic layer is integrally bonded at a position straddling the outer peripheral portion of the concave portion and the back surface of the molded product for maintaining the button shape.

Further, the present invention provides a decorative sheet having at least a design layer provided on one surface of a base sheet having excellent rigidity.
Perform three-dimensional molding using a three-dimensional molding die so as to form a key button part protruding toward the base material sheet for each predetermined position, and then place this between injection molding dies and clamp the mold. A cavity is formed between a concave portion present on the back side of the key button portion of the decorative sheet and a mold having a gate portion, and a molten molding resin made of a hard resin is injected into the cavity to enter the concave portion. In the method for obtaining a key mat member by integrally forming and bonding a molded product for button shape maintenance simultaneously with molding, as a decorative sheet, the outer peripheral portion and the inner peripheral portion of the concave portion on the surface of the base material sheet on the side of the design layer. A configuration in which a rubber elastic layer is provided at a position straddling the portion is used.

Embodiments of the present invention will be described below in detail with reference to the drawings.

1 and 6 are cross-sectional views showing an embodiment of the key mat member according to the present invention. FIG. 2 is a cross-sectional view showing a decorative sheet three-dimensionally formed in the process of manufacturing the key mat member of FIG. FIG. 3 is a cross-sectional view showing one step of the method for manufacturing the key mat member of FIG. 1. FIG. 4 shows a decorative sheet to which a button-shape-maintaining molded product is integrally bonded in the process of manufacturing the key mat member of FIG. 5 is a cross-sectional view showing one step of a method for manufacturing the key mat member of FIG. 1, FIG. 7 is a cross-sectional view showing a three-dimensionally shaped decorative sheet in the process of manufacturing the key mat member of FIG. 6, and FIG. FIG. 7 is a cross-sectional view illustrating one process of a method of manufacturing the key mat member of FIG. In the figure, 1 is a key mat member,
2 is a decorative sheet, 3 is a molded product for maintaining button shape, 4 is a base sheet, 5 is a key button portion, 6 is a concave portion, 8 is a light-shielding colored layer, 9 is a translucent colored layer, and 11 and 19 are Rubber elastic layer, 1
2, 13, 16, 20, 21 are molds, 13a, 16a,
21a is a gate portion, 14, 17, 22 are cavities, 1
Reference numerals 5 and 18 denote molding resins, respectively.

According to the present invention, a decorative sheet 2 having at least a design layer provided on one surface of a base sheet 4 having excellent rigidity projects at a predetermined position toward the base sheet 2 to form a key button portion 5. In the key mat member 1 in which the molded product 3 for maintaining the button shape made of a hard resin is integrally bonded in the concave portion 6 existing on the back side of the key button portion 5 of the decorative sheet 2, The periphery of the portion 5 is reinforced by backing the base sheet 4 with rubber elastic layers 11 and 19 (see FIGS. 1 and 6). In a first mode, the rubber elastic layer is formed of a molded resin layer and is positioned so as to straddle the outer peripheral portion of the concave portion and the back surface of the molded product for maintaining the button shape (see FIG. 1). As a second aspect, the rubber elastic layer is formed of a printing layer, and is located on the surface of the base material sheet on the design layer side so as to straddle the outer peripheral portion and the inner peripheral portion of the concave portion. (See FIG. 6).

First, the decorative sheet 2 used in the present invention will be described below.

As the base sheet 2, a single-layer film selected from resins such as polycarbonate, polyamide, polyimide, polyester, acrylic, olefin, and fluorine, or a laminated film of two or more types selected from the above films, Or polycarbonate / PB
It is preferable to use a copolymer film made of an alloy such as T or polycarbonate / PET. The film thickness is 50-250μ
m is preferred. If the sheet is less than 50 μm, it cannot follow the elongation during three-dimensional molding.
There is a high risk of breaking at the periphery of the. On the other hand, if it exceeds 250 μm, it takes a long time to heat the film to an optimal state of three-dimensional molding, and the production efficiency is poor. Even if the role of the base sheet as a surface protective layer is taken into consideration, no additional thickness is required, which leads to an increase in cost. Further, it is preferable to use the substrate sheet 4 having excellent transparency in view of the visibility of the design layer on the back surface, particularly when the key mat member 1 is of an illuminating type.

The design layer is formed by a key button portion 5 of the base sheet 4.
Is formed on the surface that does not protrude. It is preferable that the design layer formed as the outermost layer also has an adhesive force to the molding resin.

For example, when the key mat member 1 is of an illuminating type, the symbol layer is formed of a light-shielding colored layer 8 having a character pattern such as a character or a symbol on the top surface of the key button part 5 and the pattern pattern. Transparent colored layer 9 formed to cover
It is composed of Urethane,
It is preferable to use a polyester two-component curable or one-component resin having excellent heat resistance as a binder and a coloring ink containing a pigment or dye of an appropriate color as a coloring agent. As a method of forming the pattern layer, a normal printing method such as an offset printing method, a gravure printing method, and a screen printing method may be used. In the case of a single color, a coating method such as a gravure coating method, a roll coating method, and a comma coating method can be adopted.

Further, a metal thin film layer may be used as a design layer. The metal thin film layer is for expressing metallic luster, and is formed by a vacuum evaporation method, a sputtering method, an ion plating method, a plating method, or the like. Aluminum, nickel, gold, platinum, chromium, iron, copper, tin, indium, silver, titanium, lead,
Use metals such as zinc, their alloys or compounds. In particular, when a metal thin film layer is provided in a portion stretched by molding, it is preferable to provide a cluster vapor-deposited film of indium or tin.

An adhesive layer may be provided on the surface of the base sheet 2 on which the design layer 5 is formed. As the material of the adhesive layer, an adhesive ink composed of an acrylic resin, a polycarbonate resin, a vinyl chloride-vinyl acetate copolymer resin or the like may be appropriately selected and used depending on the injection molding resin to be integrated. Adhesive ink is used as a method for forming an adhesive layer, such as a normal printing method such as an offset printing method, a gravure printing method, a screen printing method, a gravure coating method, a roll coating method,
A coating method such as a comma coating method may be used.

In order to obtain the key mat member 1 of the first embodiment by using the decorative sheet 2 having such a configuration, the following should be performed (see FIGS. 1 to 5).

First, the decorative sheet 2 having at least a design layer provided on one surface of the base sheet 4 having excellent rigidity is prepared by using a three-dimensional molding die (not shown) at predetermined positions of the base sheet 4. Three-dimensional molding is performed so as to form the key button portion 5 protruding to the side (see FIG. 2). As a mold for three-dimensional molding,
A convex or concave mold is selected according to the shape of a molded article to be molded, and a mold provided with a suction hole is used. The three-dimensional molding is performed by heating and softening the decorative sheet 2 with a heat source, and performing vacuum suction and / or air pressure to bring the decorative sheet 2 into close contact with the surface of the three-dimensional molding die.

Next, the three-dimensionally formed decorative sheet 2 is arranged between the injection molding dies 12 and 13 of the button shape maintaining molded product 3. At this time, the decorative sheet 2 may be fed one by one, or a necessary portion of the long decorative sheet 2 may be sent intermittently.

Next, the molds 12 and 13 are closed to form a cavity 14 between the concave portion 6 existing on the back side of the key button portion 5 of the decorative sheet 2 and the mold 13 having the gate portion 13a. A molding resin 15 made of a hard resin in a molten state is injected into the cavity 14 (see FIG. 3).
5 is solidified to form the molded product 3 for maintaining the button shape in the cavity 14 and, at the same time, it is integrally adhered to the concave portion 6 on the back side of the key button portion 5 of the decorative sheet 2 (see FIG. 4). . As the molding resin 15 which becomes the molded product 3 for maintaining the button shape, a hard resin such as polycarbonate, acrylic, or ABS is used so as not to be damaged when input with a nail or a pen tip.

Next, the mold 1 is placed in the mold 12 so as to leave the decorative sheet 2 in which the molded product 3 for maintaining the button shape is integrated.
After opening the molds 2 and 13, the mold 13 having the gate portion 13 a is replaced with another mold 16, and the mold is clamped to form the decorative sheet 2 and the gate on which the molded product 3 for maintaining the button shape is integrally bonded. A cavity 17 is formed between another mold 16 having a portion 16a so as to straddle the outer peripheral portion of the recess 6 and the back surface of the molded product 3 for maintaining the button shape. The molten molding resin 18 made of a material is injected (see FIG. 5), and the molding resin 15 is solidified, so that rubber elasticity is provided at a position straddling the outer peripheral portion of the concave portion 6 and the back surface of the button shape maintaining molded product 3. Layer 11
To obtain a key mat member 1 (see FIG. 1). As the molding resin 18 which becomes the rubber elastic layer 11, in order to disperse the keying stress in a portion where the keying stress is concentrated at the time of input, and to hold both together when the base sheet is broken, polyester-based, polyurethane-based, A thermoplastic elastomer resin such as polyolefin is used. In order to provide the key mat member 1 with a light-shielding property, a coloring pigment such as carbon black may be kneaded into the molding resin 18 to be the rubber elastic layer 11.

In the step of forming the rubber elastic layer 11, the mold 13 having the gate 13 a used in the step of forming the button-shape-maintaining molded article 3 is separated from another mold 16.
The molded product for button shape maintenance 3
After molding, once the decorative sheet 2 in which the button-shape-maintaining molded product 3 is integrated is taken out from between the molds 12 and 13,
This may be arranged between different molds for molding the rubber elastic layer 11.

In order to obtain the key mat member 1 of the second embodiment, the following is preferable (see FIGS. 6 to 8).

First, in addition to the above-described structure, the decorative sheet 2 has a rubber elastic layer 19 on the surface of the base material sheet 4 on the side of the design layer and straddling the outer peripheral portion and the inner peripheral portion of the concave portion. Is prepared. This rubber elastic layer 19
May be provided between the base sheet 4 and the printing layer or the coating layer formed thereon, or may be provided in any of the respective layers, or as an outermost layer as shown in FIG. It may be provided. The rubber elastic layer 19 is made of a transparent material such as polyester, polyurethane, or polyolefin, in order to disperse the keying stress in a portion where the keying stress is concentrated at the time of input, and to hold both together when the base sheet is broken. Use a suitable thermoplastic elastomer resin. As a method for forming the rubber elastic layer 19, a normal printing method such as an offset printing method, a gravure printing method, and a screen printing method may be used.

Thereafter, as in the first embodiment, three-dimensional molding is performed using a three-dimensional molding die (not shown) so as to form key button portions 5 protruding toward the base material sheet 4 at predetermined positions. (See FIG. 7).

Next, similarly to the first embodiment, the three-dimensionally formed decorative sheet 2 is disposed between the injection molding dies 20 and 21 of the button-shape-maintaining molded product 3.

Next, similarly to the first embodiment, the dies 20, 2
The mold 1 is closed to form a cavity 22 between the concave portion 6 present on the back side of the key button portion 5 of the decorative sheet 2 and the mold 21 having the gate portion 21a. The molded resin 15 in a molten state is injected (see FIG. 7), and the molded resin 15 is solidified to form the molded product 3 for maintaining the button shape in the cavity 22, and at the same time, the key button portion 5 of the decorative sheet 2 is formed. The key mat member 1 is obtained by integrally bonding the inside of the concave portion 6 existing on the back side (see FIG. 8).

In both the first and second embodiments, after the key mat member 1 is obtained, the key mat member 1 is taken out of the mold. 2 can be trimmed. If the decorative sheet 2 is punched into a desired shape in advance, trimming of the decorative sheet 2 is unnecessary. In addition, the mold for injection molding can be applied to either a vertical injection molding machine or a horizontal injection molding machine.

The key mat member 1 of the present invention as described above
Is a material in which the periphery of the key button portion 5 is reinforced by backing the base sheet 4 with rubber elastic layers 11 and 19 (see FIGS. 1 and 6), so that the keying stress is concentrated at the time of input. The keying stress is dispersed at the portions by the rubber elastic layers 11 and 19, and both are held together by the rubber elastic layers 11 and 19 when the base sheet is broken. Therefore, the key mat member 1 of the present invention is excellent in the keying characteristic function that can withstand long-term use.

[0033]

<Example 1> A polycarbonate film having a thickness of 125 µm was used as a base sheet, and a light-shielding colored layer having a cut pattern was formed thereon by a screen printing method using a urethane two-part curable ink at a film thickness of 5 µm. A translucent colored layer having a thickness of 3 μm was formed on the pattern portion of the cut pattern by applying the urethane two-component curable ink by a screen method.
Then, an adhesive layer made of a vinyl chloride-vinyl acetate copolymer resin was formed with a thickness of 5 μm by a screen printing method to obtain a decorative sheet.

Next, this decorative sheet was heated 140 by a heat source.
Heated to ℃ to soften and vacuum suction with 1 atm suction force to make it adhere to the surface of the three-dimensional mold,
Using a three-dimensional molding die, three-dimensional molding was performed so as to form a plurality of key button portions each having a length of 2 mm, a width of 3 mm, and a height of 2 mm protruding toward the base material sheet at predetermined positions.

Next, this is arranged between injection molding dies, and the mold is clamped to form a cavity between the concave portion present on the back side of the key button portion of the decorative sheet and the mold having the gate portion. A molded resin for maintaining the button shape was integrally bonded into the recess by injecting a molten molding resin made of a polycarbonate resin into the cavity.

Lastly, the mold having the gate portion is replaced with another mold, and the mold is closed and the decorative sheet having the button-shape-maintaining molded product integrally bonded thereto and another mold having the gate portion are joined together. A cavity positioned so as to straddle the outer peripheral portion of the concave portion and the inner peripheral portion of the back surface of the button-shape-maintaining molded product is formed therebetween, and a molten molding resin made of a polyester elastomer is injected into the cavity. As a result, a rubber elastic layer was integrally bonded to the outer peripheral portion of the concave portion and the back surface of the molded product for maintaining the button shape to obtain a key mat member.

A keying test was conducted on this key mat member.
While the result was that the vicinity of the periphery of the key button portion was broken around 10,000 times, the present example showed no break even after clearing 100,000 times. In addition, in the keying test, load 1
kg and a drop of 0.4 m / m.

Example 2 A 125 μm-thick polycarbonate film was used as a base sheet, and a light-shielding colored layer having a cut pattern was formed on the base sheet by screen printing using a urethane two-part curable ink to a thickness of 5 μm. And
Then, a light-transmissive colored layer having a thickness of 3 .mu.
m, formed by screen printing, and then, using a urethane elastomer ink, a rubber elastic layer is formed by screen printing at a position straddling the outer peripheral portion and the inner peripheral portion of the concave portion formed by the three-dimensional molding in the subsequent step. A decorative sheet was obtained by forming a film having a thickness of 3 μm and then forming an adhesive layer made of a vinyl chloride-vinyl acetate copolymer resin system by a screen printing method to a film thickness of 5 μm.

Next, the decorative sheet 2 is heated by a heat source for 15 minutes.
By heating to 0 ° C. to soften and vacuum suction with a suction force of 1 atm, it was brought into close contact with the surface of the three-dimensional molding die, and was projected to the base sheet side at predetermined positions using the three-dimensional molding die. Height 2mm x width 2.5mm x height 2mm
3D molded to form a plurality of key buttons.

Next, this is disposed between injection molding dies, and the mold is clamped to form a cavity between the concave portion present on the back side of the key button portion of the decorative sheet and the mold having the gate portion. By injecting a molten molding resin made of a polycarbonate resin into the cavity, a molded product for maintaining the button shape is integrally bonded to a concave portion present on the back side of the key button portion of the decorative sheet to obtain a key mat member. Was.

A key tapping test was performed on this key mat member.
The result was that the vicinity of the periphery of the key button portion was broken around 10,000 times, whereas the result of this example was no break even after clearing 100,000 times. In addition, in the keying test, load 1k
g, drop 0.4 m / m.

[0042]

The key mat member and the method of manufacturing the same according to the present invention have the following advantages because of the construction described above.

That is, a decorative sheet having at least a design layer provided on one surface of a base sheet having excellent rigidity is three-dimensionally formed so as to protrude toward the base sheet side at predetermined positions to form a key button portion, In a key mat member in which a molded product for maintaining a button shape made of a hard resin is integrally bonded in a concave portion present on the back side of a key button portion of the decorative sheet, a portion where stress is always applied during long-term use, that is, a key Since the vicinity of the periphery of the button portion is backed and reinforced by the rubber elastic layer, a key mat member having significantly improved keying test characteristics as compared with the conventional specification can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a key mat member according to the present invention.

FIG. 2 is a cross-sectional view showing a decorative sheet formed three-dimensionally in a process of manufacturing the key mat member of FIG.

FIG. 3 is a sectional view showing one step of a method for manufacturing the key mat member of FIG.

FIG. 4 is a cross-sectional view showing a decorative sheet to which a molded product for maintaining a button shape is integrally bonded in a manufacturing process of the key mat member of FIG. 1;

FIG. 5 is a cross-sectional view showing one step of a method of manufacturing the key mat member of FIG.

FIG. 6 is a sectional view showing an embodiment of the key mat member according to the present invention.

FIG. 7 is a cross-sectional view showing a decorative sheet formed three-dimensionally in a process of manufacturing the key mat member of FIG.

FIG. 8 is a cross-sectional view showing one step of a method of manufacturing the key mat member of FIG.

FIG. 9 is a cross-sectional view showing one embodiment of a key mat member according to the related art.

FIG. 10 is a view showing a defect of a key mat member according to the related art.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 key mat member 2 decorative sheet 3 molded product for maintaining button shape 4 base sheet 5 key button portion 6 recess 7 metal dome 8 light-shielding colored layer 9 translucent colored layer 10 crack 11 rubber elastic layer 12 mold 13 gold Mold 13a Gate part 14 Cavity 15 Molding resin 16 Mold 16a Gate part 17 Cavity 18 Molding resin 19 Rubber elastic layer 20 Mold 21 Mold 21a Gate part

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B29L 31:00 B29L 31:00

Claims (5)

[Claims] 1. A decorative sheet having at least a design layer provided on one surface of a base sheet having excellent rigidity is three-dimensionally formed so as to protrude toward a base sheet side at predetermined positions to form a key button portion, In a key mat member in which a molded product for maintaining a button shape made of a hard resin is integrally adhered in a concave portion present on the back side of the key button portion of the decorative sheet, the periphery of the key button portion is lined with a rubber elastic layer. A key mat member characterized by being reinforced. 2. The key mat member according to claim 1, wherein the rubber elastic layer is formed of a molded resin layer, and is located so as to straddle the outer peripheral portion of the concave portion and the back surface of the molded product for maintaining the button shape. 3. The rubber elastic layer is formed of a printing layer, and is located on the surface of the base material sheet on the side of the design layer and straddles the outer peripheral portion and the inner peripheral portion of the concave portion. The key mat member described in the above. 4. A three-dimensional molding method for a decorative sheet having at least a design layer provided on one surface of a base sheet having excellent rigidity so as to form key buttons protruding toward the base sheet at predetermined positions. Three-dimensional molding using a mold, then place this between injection molding dies, close the mold, and place between the concave part on the back side of the key button part of the decorative sheet and the mold having the gate part. Forming a cavity, a method of obtaining a key mat member by integrally molding and bonding a molded product for button shape maintenance in the concave portion by injecting a molten molding resin made of a hard resin into the cavity,
After forming the button-shape-maintaining molded article, open the mold, and then place a decorative sheet integrally bonded with the button-shape-maintaining molded article between another mold or separate the mold having a gate. The mold is closed and the molded product for button shape maintenance is integrated and bonded between the decorative sheet and another mold having a gate portion. Forming a cavity positioned so as to straddle the molded product back surface, and injecting a molded resin in a molten state made of a rubber elastic material into the cavity, the outer peripheral portion of the concave portion and the molded product back surface for button shape maintenance. A method for manufacturing a key mat member, wherein a rubber elastic layer is integrally adhered at a position straddling the rubber mat. 5. A three-dimensional molding method for a decorative sheet having at least a design layer provided on one surface of a base sheet having excellent rigidity so as to form key buttons protruding toward the base sheet at predetermined positions. Three-dimensional molding using a mold, then place this between injection molding dies, close the mold, and place between the concave part on the back side of the key button part of the decorative sheet and the mold having the gate part. Forming a cavity, a method of obtaining a key mat member by integrally molding and bonding a molded product for button shape maintenance in the concave portion by injecting a molten molding resin made of a hard resin into the cavity,
A key mat member having a rubber elastic layer provided on a surface of the base material sheet on the design layer side of the base material sheet and straddling a peripheral outer portion and a peripheral inner portion of the concave portion as the decorative sheet. Manufacturing method.