JPH0817282A - Manufacture of keyboard switch, and composite member for manufacture of keyboard switch - Google Patents

Abstract

PURPOSE:To integrate a pushbutton member and a key top member in a thin form in one process by binding fused thermoplastic polyester elastomer material injected into a cavity to a middle layer material formed on a composite member by heat. CONSTITUTION:Fused thermoplastic polyester elastomer material is injected into a cavity C of a die to be bound to a middle layer material 41 formed on one surface of a composite member by heat. After that, a movable side die plate 61 is opened from a fixed side die plate 52, an ejector pin 67 is moved forward, a pressed part 21 of a moulded pushbutton member 20 is released by pushing force, and a changeable part 22 and a base panel part 23 are also released. At this time, a vent hole 69 in the pin 67 is connected to a release passage 66 to be released to an atmospheric pressure, and a key top member 30 is released from suction of the pin 67 to be integrated with the pressed part 21 through a middle layer. A thin keyboard switch of which display part function is not reduced can thus be manufactured in a simple process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a keyboard switch and a composite member for manufacturing a keyboard switch.

[0002]

2. Description of the Related Art As a keyboard switch used for audio equipment, video equipment, OA equipment, telephone equipment such as touch-tone phones and cordless phones, calculators, and other devices, a deformable portion having a spring function by elasticity is provided on a base portion. 2. Description of the Related Art There is known one having a push button member in which a pressed portion is integrally formed.

FIG. 14 is an explanatory view showing the structure of an example of a conventional keyboard switch. In this keyboard switch, the substrate 8 on which the pair of conductive terminal portions 86 is formed
5, a push button member 80 is formed in which a plurality of pressed portions 81 are integrally formed on a common base portion 83 via variable shape portions 82 each of which has a small thickness and extends outwardly from its outer peripheral edge. A display portion (not shown) for distinguishing each pressed portion 81 from other pressed portions 81 is formed on the upper surface of each pressed portion 81 of the push button member 80. A short-circuit contact member 84 corresponding to the conductive terminal portion 86 is provided on the bottom surface of the pressed portion 81 of the member 80. Further, on the push button member 80, the pressed portion 8
A cover member 87 having an opening 88 through which 1 is projected is arranged. Then, when the pressed portion 81 is pressed, the conductive terminal portion 86 is short-circuited by the short-circuit contact member 84.

In such a keyboard switch, the skirt-shaped deformable portion 82 elastically holds the pressed portion 81 so that it can be pressed.
For example, it can be made thinner than a keyboard switch including a push button member using an independent spring member, and is therefore suitable as a keyboard switch for a portable device.

[0005]

Conventionally, rubber such as silicone rubber has been mainly used as the material of the push button member 80 of the keyboard switch, but since rubber has high flexibility, There is a problem that a good operation feeling cannot be obtained when the pressed portion 81 is pressed with a finger. Further, there is a problem that the display portion formed on the pressed portion 81 is worn out due to long-term use and the function as the display portion is lost.

In order to solve such a problem, as shown in FIG. 15, on the pressed portion 81 of the push button member 80,
A keyboard switch is known in which a key top member 90 made of a transparent resin is arranged and a head 91 of the key top member 90 is projected from an opening 88 of a cover member 87.

However, in this configuration, in the key top member 90, a collar portion 92 having a diameter larger than the opening 88 is formed below the head portion 91 having a diameter smaller than the opening 88, and the key top member 90 is opened. It is necessary to prevent the key top member 90 from being separated from the key top member 90.
There is a problem in that the minimum thickness required for this is increased, and as a result, the effect of reducing the thickness of the keyboard switch by using the integrally molded push button member 80 is greatly diminished.

Also, the pressed portion 81 of the push button member 80.
In order to manufacture a keyboard switch having the key top member 90 provided thereon, when the respective members of the keyboard switch are assembled, each pressed portion 81 of the push button member 80 is
Since it is necessary to individually arrange the small-sized key top members 90 on the top, the assembling work becomes complicated and the productivity is low.
There is a problem.

On the other hand, it is conceivable that the key top member having a small thickness and the pressed portion 81 of the push button member 80 are integrated, but normally the adhesiveness between the transparent resin and the silicone rubber is low, so that the key top is Member and push button member 80
It is difficult to directly join the pressed portion 81 of No. 3 with sufficient strength, and a practically useful one cannot be obtained.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a thin keyboard switch having a structure in which a display portion is not worn and its function is not lost. Even if it is a thing, it is providing the method which can be manufactured easily and reliably by a very simple process.

Another object of the present invention is to provide a composite member for manufacturing a keyboard switch, which can be preferably used in the above-mentioned method for manufacturing a keyboard switch.

[0012]

A method of manufacturing a keyboard switch according to the present invention comprises a deformable shape having a small wall thickness, which is obtained by molding a thermoplastic polyester elastomer material, in which a pressed portion extends outward from its outer peripheral edge. Push button member formed integrally with the base part via the pressing part, a key top member made of transparent resin provided on the pressed part of the push button member, and the pressed part of the push button member And an intermediate layer that is provided between the key top member and the thermosetting ink or the thermosetting paint to form a display portion, and the intermediate layer covers the push button member. A method of manufacturing a keyboard switch, in which a pressing portion and the key top member are joined together, using an insert injection molding die, comprising a thermosetting ink on a transparent resin sheet. From the composite member by placing the composite member on which the intermediate layer material made of thermosetting paint or thermosetting paint is formed in the insert injection mold, and then clamping the insert injection mold. While cutting and separating the intermediate layer material and its associated key top member, the outer surface of the intermediate layer material is exposed in the cavity, and the thermoplastic material melted in the cavity of the insert injection mold By injecting a polyester elastomer material, there is a molding step of molding the push button member in a state where the pressed portion is joined to the key top member via the intermediate layer, and as a mold for the insert injection molding, in the cavity The ejector pin provided with an ejector pin at a position corresponding to the pressed portion of the push button member is used. By is extruded, characterized in that to release the push button member molded.

The manufacturing method of the present invention is a method of manufacturing the keyboard switch having the above-mentioned structure by using an insert injection molding die, which has the above-mentioned molding step, As the mold, a mold having an air passage communicating with a position corresponding to the pressed portion of the push button member in the cavity is used, and a compressed push button member is formed by sending compressed air through the air passage. It is characterized by releasing.

The composite member for producing a keyboard switch of the present invention is a composite member for producing a keyboard switch used in the method for producing a keyboard switch having the above-mentioned molding process, and is a transparent resin sheet and a key top of this transparent resin sheet. A member for cutting having a thickness smaller than the thickness of the portion serving as the key top member, which is made of an intermediate layer material formed on one surface of the portion serving as the member, and is provided around the portion serving as the key top member of the transparent resin sheet. It is formed, and the thickness of the cutting portion is 1 mm or less.

[0015]

According to the manufacturing method of the present invention, the heat of the molten thermoplastic polyester elastomer material injected into the cavity causes the thermoplastic polyester elastomer material to adhere to the intermediate layer material formed on one surface of the composite member, Since the push button member is molded in this state, both the molding of the push button member and the integration of the pressed portion of the push button member and the key top member can be molded in a single step, and as a result, It is not necessary to assemble a key top member, which requires complicated work.

Moreover, the key top member made of the transparent resin and the pressed portion of the push button member made of the thermoplastic polyester elastomer material are sufficiently joined and integrated by the intermediate layer interposed therebetween. Because
Since the minimum thickness required for the key top member can be made small, and as a result, the overall thickness of the keyboard switch can be made sufficiently small, it is possible to make it thinner, and to be used in portable devices and the like. It can be preferably used. In addition, since the display portion for identifying the pressed portion of the push button member is formed by the intermediate layer covered by the key top member, the display portion is not worn, and therefore, as the display portion. It is possible to prevent the function of is diminished.

Further, according to the manufacturing method using the die in which the ejector pin is provided at the position corresponding to the pressed portion of the push button member in the cavity, the push button formed by advancing the ejector pin is formed. Since the member is pushed out at the pressed portion, the entire push button member can be reliably released from the mold, and thus the deformable portion can be prevented from being damaged or deformed at the time of release.

Further, according to the manufacturing method using the mold in which the air passage communicating with the pressed portion of the push button member in the cavity is provided, by sending the compressed air through this air passage, Since the molded push button member is pushed out at the pressed portion, the entire push button member can be reliably released from the mold, whereby damage and deformation of the deformable portion at the time of release can be prevented.

According to the composite member for manufacturing a keyboard switch of the present invention, a cutting portion having a specific thickness smaller than the thickness of the portion serving as the key top member is formed around the portion serving as the key top member. Therefore, the part that becomes the key top member can be cut and separated from the other parts.

[0020]

Embodiments of the present invention will be described below. FIG. 1 is an explanatory sectional view showing a specific structure of an example of a keyboard switch obtained by the manufacturing method of the present invention.

In this keyboard switch, a plurality of (for example, when a keyboard switch for a telephone or the like is formed on the substrate 10 on which the conductive terminal portion 11 is formed, 3
Each of the pressed portions 21 (total of 12 in 4 rows) extends obliquely outward and downward from the outer peripheral edge of the deformable portion 2 having a small thickness.
A push-button member 20 made of a thermoplastic polyester elastomer material is integrally formed on a plate-like base portion 23 via two, and on each pressed portion 21 of this push-button member 20, a specific The key top member 30 made of a transparent resin is provided via the intermediate layer 40.
That is, the thermosetting ink or thermosetting paint is applied between the upper surface of each pressed portion 21 of the push button member 20 and the lower surface of the key top member 30 related thereto to cure the push button member. An intermediate layer 40 forming a display portion for identifying each pressed portion 21 of the member 20 is provided, and the pressed portion 21 of the push button member 20 and the key top member 30 are provided by this intermediate layer 40. They are integrally joined to each other.

Further, each pressed portion 2 of the push button member 20.
1 is formed on the bottom surface of 1 by printing, for example, conductive ink at a position facing the pair of conductive terminal portions 11.
A short-circuit contact member 25 corresponding to the conductive terminal portion 11 is provided. Further, on the push button member 20, the base 2
The cover member 15 is arranged so as to cover 3 and at least the upper part of the key top member 30 is projected upward through the opening 16 formed in the cover member 15.

The thickness of the deformable portion 22 of the push button member 20 is 0.05 mm to 0.4 mm, and particularly 0.1 mm to.
It is preferably 0.2 mm. When the thickness of the deformable portion 22 is less than 0.05 mm, the bending fatigue resistance of the deformable portion 22 becomes small, and it becomes difficult to mold the push button member 20 itself. On the other hand, when the thickness of the deformable portion 22 exceeds 0.4 mm, the push button member 20 has a heavy switching operation feeling. The thickness of the base portion 23 of the push button member 20 is preferably 0.5 mm or more, and particularly preferably 0.8 mm or more. The angle of the deformable portion 22 with respect to the base portion 23 of the push button member 20 is preferably 30 to 60 degrees.

The intermediate layer 40 is formed in a specific shape on the upper surface of the pressed portion 21 of the push button member 20, so that each pressed portion 2 of the push button member 20 is pressed.
1 is formed to have a function as a display portion for distinguishing 1 from other pressed portions 21. For example, the middle layer 4
The 0 is formed in a shape representing a number from “0” to “9”, symbols such as “#” and “*”, and other characters. Specifically, as shown in FIG. It is provided in a state of enclosing the shape, so-called hollow characters or white characters.

The intermediate layer 40 is preferably formed on the upper surface of the pressed portion 21 of the push button member 20 so that the adhesion area occupies 60% or more. It is preferable that the outline characters or the outline characters are formed. In addition, the intermediate layer 40
The thickness of is preferably 5 to 30 μm. By satisfying such conditions, the pressed portion 21 of the push button member 20 and the key top member 30 are reliably joined.

Further, in this example, the light emitting member 18 made of, for example, a light emitting diode is provided below the pressed portion 21 of the push button member 20, and thus is configured as an illuminated keyboard switch. . In such an illuminated keyboard switch, the pressed portion 21 of the push button member 20 needs to be translucent. Therefore, the thickness of the pressed portion 21 is 1 to 3 mm.
It is preferable that the pressed portion 21 is
It has sufficient strength and also has sufficient translucency.

In the present invention, the keyboard switch having the above structure is manufactured by the steps described below. First, a composite member in which an intermediate layer material that is a material for the intermediate layer is formed on one surface of the transparent resin sheet is prepared. This intermediate layer material is formed in accordance with the arrangement of a plurality of push buttons of the desired keyboard switch, specifically, the arrangement of each pressed portion of the push button member, and the portion where the intermediate layer material is formed is the key. It is a portion to be a top member (hereinafter, referred to as "key top forming portion").

For example, as shown in FIG. 2, an array of each pressed portion 21 of the push button member 20 is arranged on one surface of a rectangular sheet S made of a transparent resin having a uniform thickness as a whole and flat on both sides. (3 rows and 4 columns in the illustrated example), a thermosetting ink layer or a thermosetting coating layer that functions as a display unit is formed, and a curing process is performed to form the intermediate layer material 41, thereby forming a composite. The member 31 is obtained.

As the transparent resin material constituting the sheet S, an acrylic resin, a transparent resin obtained from acrylonitrile, butadiene and styrene (transparent ABS resin), a transparent polyester resin or a polycarbonate resin is used. be able to. The thickness of the sheet S may be usually 0.1 to 1.5 mm, and particularly preferably 0.1 to 0.7 mm.

As a material for forming the intermediate layer material 41, thermosetting ink or thermosetting paint is used, whereby the pressed portion 21 of the push button member 20 made of a thermoplastic polyester elastomer material, Good adhesion to both the key top member 30 made of a transparent resin is obtained, and a sufficient function as a joining portion for joining the two is obtained. The thermosetting ink or thermosetting paint has a thermosetting temperature of 60 to 150 ° C.,
It is preferable to use one having a temperature of 80 ° C to 120 ° C.
Further, as the thermosetting ink or the thermosetting paint, urethane curable or epoxy curable one, particularly urethane curable one is preferably used. Here, the urethane curability means that the formation of urethane bond is involved in the curing, and the epoxy curability means that the ring-opening reaction of the epoxy group is involved in the curing.

As a means for forming the thermosetting ink layer or the thermosetting paint layer, screen printing, pad printing or the like can be used. Further, in order to form the thermosetting ink layer or the thermosetting coating layer in the desired form, a method of printing the thermosetting ink layer or the thermosetting coating layer in the target form on the sheet S, or By forming a thermosetting ink layer or a thermosetting paint layer on the entire surface of the sheet S, which will be the key top member, and removing a part of the layer by, for example, laser light treatment, letters, numbers, and symbols are displayed. It is possible to use the method of forming the final form.

Intermediate layer material 41 formed on the composite member 31
May be in a completely cured state or a semi-cured state. However, the thermoplastic polyester elastomer material injected in the insert injection molding described later needs to be cured to such an extent that the intermediate layer 40 is not deformed.

The composite member 31 as described above is placed in a mold for insert injection molding, and insert injection molding is performed using a thermoplastic polyester elastomer material.

FIG. 3 is an explanatory sectional view showing a part of the construction of an example of an injection molding die which can be used in the manufacturing method of the present invention. This injection mold is a fixed-side mold 5 attached to a fixed plate (not shown) of an injection molding machine.
0 and a movable-side mold 60 attached to a movable plate (not shown) of the injection molding machine, and the fixed-side mold 50 includes a fixed-side receiving plate 51 and a fixed-side mold plate 52. The movable die 60 is configured as a so-called four-die die that is configured by the movable die plate 61 and the insert receiving plate 62.

More specifically, a movable side mold plate 61 is provided on one surface side (right side in the figure) of the insert receiving plate 62 so as to be separable from and into it.
The fixed side mold plate 52 is arranged on one surface side (right side in the drawing) of the movable side mold plate 61, and one surface side (right side in the drawing) of the fixed side mold plate 52.
The stationary side receiving plate 51 is provided so as to be detachable from and contactable with the stationary side receiving plate 51. FIG.
Is a fixed side receiving plate 51, a fixed side template 52, a movable side template 61.
Also, the insert receiving plate 62 is shown in a completely opened state.

As shown in FIG. 4, in a state where the movable side mold 60 is closed to the fixed side mold 50, the space surrounded by the fixed side mold plate 52 and the movable side mold plate 61 corresponds to the push button member 20. Form a cavity C,
A sprue K is formed on the fixed-side receiving plate 51 so as to pass through the respective central portions thereof, and a runner R is formed on the fixed-side template 52 in communication with the sprue K.
A gate G is formed so as to communicate with the cavity C.

In the movable mold plate 61, the cavity C is formed.
A space C1 corresponding to the pressed portion 21 of the push button member 20 in FIG. 3 extends as it is to form an extended space portion D that opens to the other surface of the movable side mold plate 61, and one surface of the insert receiving plate 62 has a cross section A plurality of cutting portions 63 whose contour shape is adapted to the extended space portion D of the movable side template 61 are formed so as to protrude from the surface according to the arrangement of the spaces corresponding to the pressed portions 21 of the push button member 20 in the cavity C. The insert receiving plate 62 and the movable side mold plate 6
In the state where 1 and 1 are closed, the cutting portion 63 has the movable side mold plate 6
It is configured so that it can be fitted into the extended space portion D of 1. Further, in the peripheral region of the cutting portion 63 of the insert receiving plate 62, a housing groove 64 for housing a portion other than the key top forming portion of the composite member 31 cut and separated according to a later-described manner is formed. The depth of the housing groove 64 is, for example, a size corresponding to the thickness of the composite member 31 or a size larger than that.

A through passage 67a is formed in the insert receiving plate 62 at the center of each of the cutting portions 63 and extends through the insert receiving plate 62 from one surface side to the other surface side. Further, a cylindrical ejector pin 67 is slidably provided in an airtight state, and an ejector plate 70 for advancing the ejector pin 67 in the direction toward the one side is provided at the base end of the ejector pin 67. Further, a ventilation member 68 made of a porous metal material is provided at the center of the tip of the ejector pin 67 so as to be buried and the surface thereof forms the tip surface of the ejector pin 67. A ventilation hole 69 passing through the central portion is formed, the tip end thereof extends to the ventilation member 68, and the base end thereof is opened to the outer peripheral surface of the ejector pin 67.

In the insert receiving plate 62, one end 65a is opened in the through passage 67a, and the other end is opened in the side surface of the insert receiving plate 62 so as to be connected to an appropriate pressure reducing device (not shown). Passage 65 and one end 66a thereof opens into the through passage 67a, and the other end thereof is the insert receiving plate 6
An opening passage 66 is formed on the side surface of the opening 2. The center of each of the one end 65a of the pressure reducing passage 65 and the one end 65b of the opening passage 66 is at the same distance as the moving distance of the ejector pin 67.
7 are arranged at positions separated in the same direction as the extending direction, whereby the ejector pin 67 shown in FIG.
Is in the retracted molding position, the pressure reducing passage 6
5 is connected to the vent hole 69 of the ejector pin 67 and the ejector pin 67 is in the release position in which the ejector pin 67 is advanced as shown in FIG.
7 to the ventilation holes 69.

In the present invention, a thermoplastic polyester elastomer material is used as the molding material. As the thermoplastic polyester elastomer material, a thermoplastic polyester elastomer (hereinafter, also referred to as “component (A)”) alone or a rubber component (hereinafter referred to as “component (A)”) containing a diene rubber and / or an acrylic rubber , "(B) component"), plasticizer (hereinafter,
Also referred to as "(C) component". ) And a silicone oil (hereinafter, also referred to as “component (D)”) can be used as a thermoplastic polyester elastomer composition.

The thermoplastic polyester elastomer as the component (A) is a polyester block copolymer,
The polymer chain has a high melting point crystalline segment mainly composed of an aromatic polyester unit and a low melting point polymer segment mainly composed of an aliphatic polyether unit and / or an aliphatic polyester unit.

The aromatic polyester unit of the high melting point crystal segment which is the hard segment is formed from an acid component and a polyol component.

The acid component forming the aromatic polyester unit is preferably an aromatic dicarboxylic acid, and in particular,
It is preferably terephthalic acid and / or 2,6-naphthalenedicarboxylic acid. In addition to terephthalic acid and / or 2,6-naphthalenedicarboxylic acid, other aromatic dicarboxylic acids such as isophthalic acid, adipic acid, sebacic acid, cyclohexane-1,4
-A small amount of an aliphatic dicarboxylic acid such as dicarboxylic acid or dimer acid may be used in combination.

The polyol component forming the aromatic polyester unit is preferably a glycol having 2 to 12 carbon atoms, and examples thereof include ethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, hexanediol and decanediol. .

The lower limit of the melting point of the high melting point crystalline segment is not particularly limited, but in general, the homopolymer has a melting point of 150 ° C. or higher, preferably 170 ° C. or higher, more preferably 190 ° C. or higher.

The aliphatic polyether unit constituting the low melting point polymer segment which is a soft segment is formed of polyalkylene glycol, and specific examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol and polyethylene. Examples thereof include glycol-polypropylene glycol block copolymers, and polytetramethylene glycol is particularly preferable. These polyalkylene glycols preferably have a carbon to oxygen ratio of 2 to 4.5, and these can be used alone or in combination of two or more.

The aliphatic polyester unit which is another unit constituting the low melting point polymer segment is mainly formed of an aliphatic dicarboxylic acid and a polyol.

Examples of the aliphatic dicarboxylic acid forming the aliphatic polyester unit include succinic acid, adipic acid,
Examples thereof include sebacic acid and decanedicarboxylic acid, and in addition to these aliphatic dicarboxylic acids, a small amount of aromatic dicarboxylic acid such as isophthalic acid may be used in combination.

The polyol component forming the aliphatic polyester unit is preferably a glycol component having 2 to 12 carbon atoms, and specific examples thereof include a polyol forming the aromatic polyester unit of the high melting point crystalline segment. Examples are the same as those exemplified as the components.

The aliphatic polyester unit is obtained by polycondensing the above-mentioned aliphatic dicarboxylic acid and the polyol component by a usual method, and may be a homopolyester or a copolyester, or may open a cyclic lactone. It may be a polylactone obtained by ring polymerization, for example, poly-ε-caprolactone.

The upper limit of the melting point of the low melting point polymer segment is not particularly limited, but in general, the melting point of the homopolymer is 130 ° C. or lower, preferably 100 ° C. or lower. The molecular weight of the low melting point polymer segment is usually 4
It is from 00 to 6000.

The composition ratio of the high melting point crystalline segment and the low melting point polymer segment in the thermoplastic polyester elastomer is preferably 95/5 to 5/95 by weight ratio, and more preferably 70/30 to 30 /. 70.
As the thermoplastic polyester elastomer, one having a softening point of 100 ° C. or higher is preferable.

The polyester block copolymer particularly preferably used as the thermoplastic polyester elastomer has a high melting point crystalline segment of polytetramethylene terephthalate or polytrimethylene terephthalate-
The low-melting polymer segment is formed of 2,6-naphthalate, and the low-melting polymer segment is a polyether such as polytetramethylene glycol, polytetramethylene adipate, poly-
It is formed of polyester such as ε-caprolactone.

It is also possible to use, as a part of the dicarboxylic acid or glycol, a polycarboxylic acid, a polyfunctional hydroxy compound, or an oxy acid copolymerized. When these polyfunctional components are copolymerized in the range of 3 mol% or less, they act effectively as a viscosity increasing component.
Examples of such a polyfunctional component include trimellitic acid, trimesic acid, pyromellitic acid, benzophenonetetracarboxylic acid, butanetetracarboxylic acid, glycerin, pentaerythritol, or esters thereof,
An acid anhydride etc. can be mentioned.

The thermoplastic polyester elastomer can be produced by a usual polymerization method. A preferable polymerization method is to heat an aromatic dicarboxylic acid or its alkyl ester and a low melting point segment-forming diol to about 150 to 260 ° C. in the presence of a catalyst to carry out an esterification reaction or a transesterification reaction, and then A method for obtaining a thermoplastic elastomer by carrying out a polycondensation reaction while removing excess low-molecular diol under vacuum, a high-melting point polyester segment-forming prepolymer and a low-melting point polymer segment-forming prepolymer prepared in advance, A method for obtaining a thermoplastic polyester elastomer by mixing a bifunctional chain extender that reacts with the terminal groups of the prepolymer of (1) and reacting the mixture, keeping the system in a high vacuum, and removing volatile components, and a high degree of polymerization. The high-melting point polyester and lactones are heated and mixed, and the lactone is subjected to ring-opening polymerization. A method of obtaining a thermoplastic polyester elastomers by ether exchange reaction.

The rubber component which is the component (B) is composed of both or at least one of a diene rubber and an acrylic rubber. As the diene rubber, natural rubber,
Polyisoprene rubber, polybutadiene rubber, styrene-
Butadiene rubber, acrylonitrile-butadiene rubber,
Chloroprene rubber, n-butyl acrylate-butadiene rubber, n-butyl acrylate-acrylonitrile-
Butadiene rubber may be used.

Examples of the acrylic rubber include acrylic acid ester rubber and ethylene-acrylic acid ester copolymer rubber. These acrylic rubbers include those having an epoxy group, an active chlorine group, a carboxyl group or the like which form a crosslinking point. It may be a copolymer of monomers having a reactive group.

Of these, preferred are acrylonitrile-butadiene rubber, n-butyl acrylate-butadiene rubber, n-butyl acrylate-acrylonitrile-butadiene rubber and acrylic rubber, and particularly preferred are acrylonitrile-butadiene rubber. .

Further, as the above-mentioned component (B), it is preferable to use one having a polar group introduced therein. The push button member 20 obtained from the thermoplastic polyester elastomer material containing the component (B) is
The adhesiveness with the intermediate layer 40 is high.

As the thermoplastic polyester elastomer material, it is preferable to use a material in which the above component (B) is dispersed and mixed in the thermoplastic polyester elastomer as the component (A).

Examples of the plasticizer which is the component (C) include a process oil or a softening agent for mineral oil rubber called extension oil, dioctyl phthalate, dibutyl phthalate, diethyl phthalate, butyl benzyl phthalate, di-2-. Phthalates such as ethylhexyl phthalate, diisodecyl phthalate, diundecyl phthalate, diisononyl phthalate, tricresyl phosphate, triethyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate,
Trimethyl phosphate, tributoxyethyl phosphate, tris-chloroethyl phosphate, tris-dichloropropyl phosphate, condensed phosphoric acid ester, triphenyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate , Trilauryl phosphate, tricetyl phosphate, tristearyl phosphate, trioleyl phosphate and other phosphoric acid esters, trimellitic acid octyl ester, trimellitic acid isononyl ester, trimellitic acid isodecyl ester and other trimellitic acid esters, Dipentaerythritol esters, dioctyl adipate, dimethyl adipate, di-
2-ethylhexyl adipate, diisobutyl adipate, dibutyl adipate, diisodecyl adipate, dibutyl diglycol adipate, di-2-ethylhexyl azelate, dioticule azelate, dioctyl sebacate, di-2-ethylhexyl sebacate, methylacetyl ricinolate, etc. Fatty acid esters, pyromellitic acid esters such as octyl pyromellitic acid, epoxidized soybean oil, epoxidized linseed oil, epoxy plasticizers such as epoxidized fatty acid alkyl ester (eg epoxidized fatty acid octyl ester), adipate ether Examples include polyether plasticizers such as esters, polyether esters, and polyethers. These plasticizers can be used alone or in combination of two or more.

The plasticizer which is the component (C) is used for the purpose of improving the fluidity of the thermoplastic polyester elastomer material and lowering the hardness thereof. Depending on the purpose of use of the plasticizer, the component (A) is used. Selectively acting on,
Those which selectively act on the component (B), those which act on both the components (A) and (B), and the like can be appropriately selected.

When a plasticizer is used, from the viewpoint of compatibility with other components, phthalic acid esters, phosphoric acid esters, epoxy plasticizers, polyether plasticizers,
It is preferable to use trimellitic acid esters and the like, and it is particularly preferable to use phthalic acid esters, trimellitic acid esters and polyether plasticizers. By using such a plasticizer, it is possible to prevent bleeding from occurring in the obtained molded product.

The silicone oil as the component (D) has the effect of improving the releasability from the mold when the push button member 20 is manufactured by injection molding. Specific examples of the silicone oil include dimethylpolysiloxane, methylpolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, and some of these polysiloxanes modified with an epoxy group or an amino group. Among these, dimethylpolysiloxane is preferable, and particularly preferable is one having a viscosity of 10 to 3000 at 25 ° C.
It is a silicone oil composed of 0 cs of dimethylpolysiloxane.

In the above, the ratio of the components (A), (B) and (C) used is as follows: (A) component: (B) component:
Component (C) is 60 to 100% by weight: 0 to 20% by weight: 0
To 30% by weight, preferably 60 to 98% by weight: 2
-15 wt%: 0-25 wt%, more preferably 70
˜98% by weight: 2 to 10% by weight: 0 to 20% by weight. When the ratio of the component (A) is less than 60% by weight, the thermoplastic polyester elastomer material has low workability, and the push button member 20 obtained from the thermoplastic polyester elastomer material has a mechanical strength. Will be small. When the proportion of the component (B) exceeds 20% by weight, the thermoplastic polyester elastomer material has low processability, and the push button member 20 obtained from the thermoplastic polyester elastomer material has a mechanical strength. Will be small. When the proportion of the component (C) exceeds 30% by weight, bleed-out of the plasticizer occurs in the push button member 20 obtained from the thermoplastic polyester elastomer material. The adhesiveness with is low.

The proportion of the component (D) used is 0 to 1 part by weight, preferably 0.01, based on 100 parts by weight of the mixed component of the components (A), (B) and (C). ~
It is 1 part by weight, more preferably 0.01 to 0.5 part by weight, particularly preferably 0.01 to 0.2 part by weight. When the proportion of the component (D) exceeds 1 part by weight, the push button member 20 obtained from the thermoplastic polyester elastomer material undergoes bleed-out of the component (D). The adhesiveness with the intermediate layer 40 is low.

In the above thermoplastic polyester elastomer material, if necessary, various additives, for example, molding aids such as known crystal nucleating agents and lubricants, known antioxidants, heat-resistant materials such as ultraviolet absorbers, etc. Weather resistance stabilizer, antistatic agent,
A release agent, a coloring agent such as a dye or a pigment, and the like can be added.

In the present invention, each of the above components is used as a thermoplastic polyester elastomer material in various extruders,
It is preferable to use the one melt-kneaded with a Banbury mixer, a kneader, a mixing roll, or a combination thereof. In melt-kneading, the addition order of each component is not particularly limited, for example, all components can be kneaded at the same time, or after kneading any component, other components may be added and kneaded. it can.

Regarding the component (D), for example, a method in which the components (A), (B) and (C) are melt-kneaded and mixed by a Henschel mixer, ribbon blender, tumbler, etc., (A) It can be added by a method of adding the components during or after the polymerization step. Alternatively, the master batch may be prepared by previously mixing the component (D) with the component (A) at a high concentration, and the master batch may be mixed so that the final ratio is obtained.

The thermoplastic polyester elastomer material obtained as described above has a JIS A hardness of 6
It is preferably from 0 to 98. When the JIS A hardness is less than 60, the push button member 20 obtained from the thermoplastic polyester elastomer material lacks a click feeling and has low responsiveness as a switch. When the JIS A hardness exceeds 98, the push button member 20 obtained from the thermoplastic polyester elastomer material has a large load necessary to press the pressed portion 21 of the push button member 20. As a result, the responsiveness is low.

The thermoplastic polyester elastomer material has an MFR (melt flow rate) of 20 g / 10.
It is preferably at least min. Where MF
R is JIS K7210 (230 ° C, 2.16k
Refers to what is measured according to g). 20g MFR
When it is less than / 10 min, the thermoplastic polyester elastomer material has low fluidity in a melted state, so that it is difficult to form the deformable portion 22 having a small wall thickness.

Using the above-mentioned thermoplastic polyester elastomer material, the push button member 20 having the key top member on the pressed portion 21 is obtained as follows. That is, in the injection molding machine to which the insert injection molding die described above is attached, as shown in FIG. 6A, a composite member is provided between the insert receiving plate 62 and the movable side die plate 61 in the die. 31 is arranged such that the outer surface of the intermediate layer material 41 faces the opening of the extended space portion D of the movable side mold plate 52, and in this state, the depressurizing device connected to the depressurizing passage 65 is driven to eject the ejector. Pin 67
The inside of the ventilation hole 69 is depressurized, whereby the composite member 31 is adsorbed and held by the tip of the ejector pin 67 via the ventilation member 68. Thereafter, as shown in FIG. 6B, when the cutting portion 63 is fitted into the extended space portion D by closing the mold, the key top on which the intermediate layer material 41 of the composite member 31 is formed. The forming portion is cut from a portion outside the outer periphery thereof to separate the key top forming portion, and the cutting portion 63 is fitted into the extension space portion D of the movable side template 61 while holding the key top forming portion, The outer surface of the intermediate layer material 41 is exposed in the cavity C. On the other hand, the portion of the composite member 31 other than the key top forming portion is housed in the housing groove 64.

In this state, as shown in FIG. 7C, the molten thermoplastic polyester elastomer material is injected into the cavity C of the mold. This injection is usually carried out by melting the thermoplastic polyester elastomer material charged in the hopper by rotating the screw to fill the tip portion of the cylinder, and then driving the screw to drive the piston.

Then, the thermoplastic polyester elastomer material in the cavity C is cooled and solidified by this mold, and the molding step is completed with the molded push button member 20 adhered to the intermediate layer material 41. After that, FIG.
(D) As shown in FIG.
When the ejector pin 67 is opened and the ejector pin 67 is moved forward, a pressing force is exerted on the pressed portion 21 of the molded push button member 20. As a result, the pressed portion 21 is released from the mold, and subsequently the deformable shape is changed. The part 22 and the base part 23 are released. At this time, the vent hole 6 of the ejector pin 67
9 is connected to the opening passage 66 to open the inside of the vent hole 69 to the atmospheric pressure, whereby the state where the key top member 30 is adsorbed by the ejector pin 67 is released. In this way, the push button member 20 in which the key top member 30 is integrally joined to the pressed portion 21 via the intermediate layer 40 is obtained. Further, by opening the insert receiving plate 62 from the movable side mold plate 61, the portion other than the key top forming portion of the cut and separated composite member 31 is naturally dropped from the accommodation groove 64 of the insert receiving plate 62 and removed. .

The keyboard switch is obtained by assembling the push button member 20 having the key top member 30 provided on the pressed portion 21 and the other members manufactured by the above process.

According to the above manufacturing method, the thermoplastic polyester elastomer material is adhered to the intermediate layer material 41 formed on one surface of the composite member 31 by the heat of the injected molten thermoplastic polyester elastomer material. Since the push button member 20 is molded in this state,
Both the molding of the push button member 20 and the integration of the pressed portion 21 of the push button member 20 and the key top member 30 can be performed in a single step, and as a result, the work of assembling the key top member 30 is unnecessary. Becomes Therefore, the keyboard switch in which the key top member 30 is provided on the pressed portion 21 of the push button member 20 can be easily manufactured by a simple process.

Further, in the above-described manufacturing method, since the mold in which the ejector pin 67 is provided at the position corresponding to the pressed portion 21 of the push button member 20 in the cavity C is used, the ejector pin 67 is moved forward. As a result, the molded push button member 20 is pushed out by the pressed portion 21, so that the molded push button member 20 as a whole can be reliably separated without applying excessive tension to the deformable portion 22 having a small thickness. Can be typed,
Thereby, the deformable portion 22 can be prevented from being damaged or deformed.

If a die in which an ejector pin is provided at a position corresponding to the base portion 23 other than the pressed portion 21 of the push button member 20 in the cavity is used, the molded push button member 20 is Although the ejector pin pushes it out at the base portion 23, since the pressed portion 21 is usually difficult to release from its shape, the thickness formed between the base portion 23 and the pressed portion 21 is large. Excessive tension may be applied to the deformable portion 22 having a small size, and as a result, the deformable portion 22 may be damaged or deformed.

In addition, the intermediate layer material 41 in the composite member 31
Since the key top forming portion formed with is cut and separated from the portion outside the outer periphery while being held by the tip end surface of the ejector pin 67, for example, the key top forming portion has a circular shape. Also does not rotate in the extended space portion D of the movable side mold plate 61, and as a result, the key top member is arranged at the intended position on the pressed portion of the push button member. And the push button member can be joined.

The keyboard switch obtained by the above method is provided between the upper surface of the pressed portion 21 of the push button member 20 made of the thermoplastic polyester elastomer material and the lower surface of the key top member 30 made of the transparent resin. An intermediate layer 40 having adhesiveness is provided on the intermediate layer 40.
Since the pressed portion 21 of the push button member 20 and the key top member 30 are joined and integrated with each other with sufficient strength, the thickness of the key top member 30 can be reduced. As a result, the overall thickness of the keyboard switch can be made sufficiently small, so that it is thin as a whole and can be suitably used for a portable device or the like. Moreover, the push button member 2
The display portion for identifying the pressed portion 21 of 0 is the intermediate layer 4
Since the intermediate layer 40 is protected by the key top member 30 and is not directly touched by the key top member 30, it is not worn and as a result, the function as a display unit is lost. Can be prevented.

In the manufacturing method of the present invention, a mold provided with an ejector pin whose tip surface shape is substantially the same as the surface shape of the key top member 30 can be preferably used.

FIG. 8 is an explanatory sectional view showing a part of the construction of another example of the insert injection molding die used in the manufacturing method of the present invention. The insert injection molding die includes a fixed-side die 50 including a fixed-side receiving plate 51 and a fixed-side die plate 52, and a movable-side die plate 60a including a movable-side die plate 61 and an insert-side receiving plate 76. ing. Specifically, the movable side mold plate 61 is provided on one surface side of the insert receiving plate 76 so as to be separable and contactable, and the fixed side mold plate 52 is arranged on the one surface side of the movable side mold plate 61. 5
A fixed side receiving plate 51 is provided on one surface side of 2 so as to be separable and contactable. The movable-side mold plate 61, the fixed-side mold plate 52, and the fixed-side receiving plate 51 have the same configurations as the insert injection mold shown in FIG.

A loading groove L for loading the composite member 31 is formed on one surface of the insert receiving plate 76, and the insert receiving plate 76 is arranged in accordance with the arrangement of spaces corresponding to the pressed portions 21 of the push button member 20 in the cavity C. A plurality of through-paths 7 extending from one surface side to the other surface side
7 a is formed, and an ejector pin 77 whose cross-sectional contour shape conforms to the extension space portion D of the movable side mold plate 61 is slidably provided in the through passage 77 a. A common push-out plate 77b for advancing the ejector pin 77 in the direction toward the one surface side is integrally provided at each base end of the ejector pin 77. In this mold, ejector pin 7
The tip portion of 7 also serves as a cutting portion for cutting the composite member 31.

At the center of the tip of the ejector pin 77, a ventilation member 78 made of a porous metal material is provided in a buried state so that the surface thereof forms the tip surface of the ejector pin 77. A vent hole 69a is formed in the central portion and the push-out plate 77b. The vent hole 69a has a tip extending to the vent member 78, and a base end opening to the side surface of the extruding plate 77b.

Also, the insert receiving plate 76 and the extruding plate 77b.
A spacer 79 is detachably provided between and. The distance between the spacer 79 and the pushing plate 77b is
It has a size corresponding to the thickness of the extension space portion D of the movable side mold plate 61, and by attaching and detaching the spacer 79,
The ejector pin 77 is moved in two steps. Specifically, the ejector pin 77 is further advanced from the initial position in the most retracted state, the molding position in a state in which the push-out plate 77b is advanced until it comes into contact with the spacer 79, and the spacer 79 being removed to further advance the molding position. It is possible to move to and from the release position in the state.

In the case of using the mold having the above construction, the outer surface of the intermediate layer member 41 of the composite member 31 is moved in the loading groove L of the insert receiving plate 76 with the ejector pin 77 in the initial position. Extended space portion D of the side template 61
It is arranged so as to face the opening of the vent hole 69 in this state.
By decompressing the inside of a, the composite member 31 is adsorbed and held by the tip end surface of the ejector pin 77 via the ventilation member 78. After that, by closing the mold and then advancing the ejector pin 77 to the molding position, when the ejector pin 77 is fitted into the extended space portion D of the movable side mold plate 61, the intermediate layer material in the composite member 31. Four
The key top forming portion on which 1 is formed is cut from the outer peripheral portion on the outer periphery thereof to separate the key top forming portion, and the ejector pin 77 holds the key top forming portion in the extended space portion D. The outer surface of the intermediate layer material 41 is inserted into the cavity C and is exposed.

In this state, after the molten thermoplastic polyester elastomer material is injected into the cavity C, the thermoplastic polyester elastomer material is cooled and solidified so that the molded push button member 20 is bonded to the intermediate layer material 41. It will be in the state of being. And the spacer 78
By detaching the ejector pin 77 and advancing the ejector pin 77 to the releasing position, a pressing force is exerted on the pressed portion 21 of the molded push button member 20, whereby the pressed portion 21 is released from the mold. Subsequently, the deformable portion 22 and the base portion 23 are released. At this time, the pressure inside the vent hole 69a of the ejector pin 77 is set to normal pressure, so that the formed push button member 20 naturally falls. In this way,
The key top member 3 is provided on the pressed portion 21 via the intermediate layer 40.
A push button member 20 in which 0s are integrally joined is obtained.

According to the above method, the ejector pin 77 is provided at the position corresponding to the pressed portion 21 of the push button member 20 in the cavity C, as in the mold shown in FIG. By moving the push button member 20 forward, the molded push button member 20 is pushed out by the pressed portion 21, so that the entire molded push button member 20 can be treated without applying excessive tension to the deformable portion 22 having a small thickness. It can be released reliably,
Thereby, the deformable portion 22 can be prevented from being damaged or deformed.

Further, the intermediate layer material 41 in the composite member 31.
The key top forming portion formed with is cut and separated from a portion outside the outer periphery in a state of being held by the tip end surface of the ejector pin 77. Therefore, for example, the key top forming portion has a circular shape. Also does not rotate in the extended space portion D of the movable side mold plate 61, and as a result, the key top member is arranged at the intended position on the pressed portion of the push button member. And the push button member can be joined.

Further, by making the shape of the tip end surface of the ejector pin 77 conform to the extension space portion D of the movable side mold plate 61, that is, substantially the same as the shape of the surface of the key top member 30, When the ejector pin 77 pushes out the push button member 20, the pushing force can be applied to the entire upper surface of the key top member 30, thereby preventing the upper surface of the key top member 30 from being damaged at the time of mold release. You can

In the manufacturing method of the present invention, a composite member continuous body formed by continuously forming a plurality of composite members may be used. FIG. 9 is an explanatory view showing an example of a composite member continuous body that can be used in the present invention. In this composite member continuous body 32, a long sheet S made of a transparent resin is used.
The group of intermediate layer materials 41 arranged according to the arrangement of the pressed portions 21 of the push button member 20 on one surface of
Are formed at regular intervals in the longitudinal direction. When such a composite member continuum 32 is used, for example, as shown in FIG.
As shown in FIG.
3, the composite member continuous body 32 is moved vertically, for example, between the insert receiving plate 62 and the movable side mold plate 61 by the winding roll 34, and each composite member in the composite member continuous body 32 is shown in FIG. It may be arranged so as to be in a state similar to the state shown in.

According to such a method, the composite member continuous body 32 is moved by a predetermined distance in the length direction thereof, whereby each composite member in the composite member continuous body 32 can be arranged with high efficiency. At the same time, the parts other than the key-top forming part in the composite member cut and separated in the preceding step can be removed in parallel, so that high time efficiency can be obtained.

In the manufacturing method having the above-mentioned molding steps, as shown in FIG. 11, the key top forming portion 3 is formed.
Composite member 3 in which cutting portion 37 is formed around 6
It is preferable to use 5. More specifically, the composite member 35 has a flat surface on one surface and a plurality of spherical surfaces formed on the other surface so as to project in a spherical shape according to the arrangement of the pressed portions 21 of the target push button member 20. Key top forming portion 36, and a groove-shaped cutting portion 3 formed around each key top forming portion 36
The sheet S2 having No. 7 and the intermediate layer material 41 formed on one surface of the key top forming portion 36 of the sheet S2. Here, the cutting portion 37 has a thickness smaller than that of the key top forming portion 36, and its size is 1 mm or less, preferably 0.6 mm or less, and its width is 0.5 to 3 mm. Is preferred.

For such a composite member 35, a sheet S2 is produced by injection molding a transparent resin material, for example, and the intermediate layer material 41 is formed on one surface of the sheet S2 in the same manner as the composite member 31 described above. It is obtained by doing.

As the injection molding method, the so-called injection compression molding method is preferably used. Specifically, the injection injection of the molding material is started in a state where the mold clamping is performed at a mold clamping pressure of 15 to 30% of the maximum mold clamping pressure of the injection molding machine used, and then 0.2 to 2 seconds. After the lapse of time, a method of molding by performing mold clamping at the maximum mold clamping pressure or a mold of 0.1
Examples include a method in which injection molding of a molding material is started in a state where the mold material is opened at an interval of 0.3 mm, and then molding is performed by performing mold clamping. By using such a method, the composite member 35 having the desired cutting portion 37 can be reliably obtained.

Further, as the mold, it is preferable to use a mold having a so-called nesting mold in which a portion forming a cavity in the mold plate is detachable. By using such a mold, in the case of producing a composite member in which the key top forming portion is formed in a different mode, it is only necessary to replace the nesting mold with one corresponding to the mode of the key top forming section. Other parts can be used in common, resulting in lower manufacturing costs.

According to such a composite member 35, a cutting portion 37 having a thickness smaller than the thickness of the key top forming portion 36 and having a thickness of 1 mm or less is formed around the key top forming portion 36. The key top forming portion 36 can be reliably cut and separated from other portions.

In the manufacturing method of the present invention, as the insert injection molding die, one having an air passage communicating with a position corresponding to the pressed portion 21 of the push button member 20 in the cavity is used. it can.

FIG. 12 is an explanatory sectional view showing a part of the structure of still another example of the insert injection molding die used in the manufacturing method of the present invention. The insert injection molding die includes a fixed-side die 50 including a fixed-side receiving plate 51 and a fixed-side die plate 52, and a movable-side die 60b including a movable-side die plate 61 and an insert-receiving plate 71. ing. Specifically, a movable side mold plate 61 is provided on one surface side of the insert receiving plate 71 so that the movable side mold plate 61 can be separated from and contacted with the movable side mold plate 61.
The fixed-side mold plate 52 is arranged on one surface side of the No. 1, and the fixed-side receiving plate 51 is provided on the one surface side of the fixed-side mold plate 52 so as to be separable from and in contact with the fixed-side mold plate 52.

In the insert receiving plate 71, a plurality of cutting portions 72 are formed on one surface thereof in the same manner as the insert receiving plate 62 of the mold having the structure shown in FIG. 73 is formed. Further, the mold of the illustrated example uses the composite member 35 having the configuration shown in FIG. 11, so that the protruding surface of the cutting portion 72 is
The shape is adapted to the key top forming portion 36 of the composite member 35. A ventilation member 73 made of a porous metal material is provided in the center of each of the cut portions 72 in a buried state so that the surface thereof forms the surface of the cut portion 72, and the central portion of the cut portion 66. An air passage 75 passing therethrough is formed, the distal end thereof extends to the ventilation member 73, and the proximal end thereof is opened to the side surface of the insert receiving plate 62. Further, the fixed-side receiving plate 51, the fixed-side mold plate 52, and the movable-side mold plate 61 have the same configuration as the insert injection molding die shown in FIG. The insert injection mold is not provided with an ejector pin.

In the case of using the mold having the above structure, the composite member 35 is provided between the insert receiving plate 71 and the movable side mold plate 61 of the mold, and the outer surface of the intermediate layer material 41 is the movable side mold plate. It is arranged so as to face the opening of the extended space portion 61 of 61, and in this state, by depressurizing the inside of the air passage 75, the composite member 3 is attached to the cutting portion 74 via the ventilation member 68.
5 is adsorbed and held. Then, in the same manner as described above, the key top forming portion 36 of the composite member 35 on which the intermediate layer material 41 is formed is cut and separated, and the molten thermoplastic polyester is melted in a state where the outer surface of the intermediate layer material 41 is exposed in the cavity C. By injecting the elastomer material into the cavity C and then solidifying by cooling, the molded push button member 20 is in a state of being bonded to the intermediate layer material 41. Then, by sending compressed air from the ventilation member 68 through the air passage 75, the pressed portion 21 of the molded push button member 20 is protruded, whereby the pressed portion 21 is released. Following this, the deformable portion 22 and the base portion 23 are released. In this way, the push button member 20 in which the key top member 30 is integrally joined to the pressed portion 21 via the intermediate layer 40 is obtained.

According to the above-mentioned method, the molded push button member 20 is projected in the pressed portion 21 by the compressed air sent through the air passage 75, so that the tension acting on the deformable portion 22 can be reduced. In the restrained state, the molded push button member 20 as a whole can be released from the mold, whereby damage and deformation of the deformable portion 22 at the time of release can be prevented.

Further, the intermediate layer material 41 in the composite member 35
Since the key top forming portion 36 in which the key top forming portion is held by the cutting portion 74 is cut and separated from a portion outside the outer periphery thereof, even if the key top forming portion has a circular shape, It does not rotate in the extended space portion D of the movable side mold plate 61, and as a result, the key top member is pushed with the key top member in a state in which it is arranged at the desired position on the pressed portion of the push button member. The button member can be joined.

Specific examples of the present invention will be described below, but the present invention is not limited thereto. <Example 1> [Production of insert injection molding die] According to the configuration shown in Fig. 3, S55C-based general metal steel was used as the material of the die, and the average porosity was 25 as the material of the ventilation member. %,
Using a porous metal “Pocerax II PM40 (manufactured by Shinto Kogyo Co., Ltd.)” having an average pore diameter of 7 μm and a hardness of HRC40, the thickness of the portion (indicated by C2 in FIG. 4) corresponding to the deformable portion of the cavity is 0.13 mm, A mold X was produced in which the angle of the portion corresponding to the deformable portion with respect to the portion corresponding to the base portion (indicated by C3 in FIG. 4) was 51 degrees.

[Preparation of Thermoplastic Polyester Elastomer Material] Thermoplastic Polyester Elastomer “PIBI
88 parts by weight of FLEX 35M (manufactured by Enichem Polymeri) and acrylonitrile butadiene rubber "JSR / N"
230S (manufactured by Japan Synthetic Rubber Co., Ltd.) "and 0.05 part by weight of silicone oil" Silicone Oil SH (manufactured by Toray Dow Corning Silicone Co., Ltd.) "are mixed by a Henschel mixer, and then by a twin-screw extruder. Heating temperature 200 ° C, screw rotation speed 150r. p. m. The thermoplastic polyester elastomer material was prepared by kneading under the conditions described above and adding 10 parts by weight of a plasticizer "SANSOCIZER DUP (manufactured by Shin Nippon Science Co., Ltd.)" from the middle of the twin-screw extruder during the kneading. JI of this thermoplastic polyester elastomer material
S A hardness is 90, MFR is 102g / 10mi
It was n. The above-mentioned thermoplastic polyester elastomer "PIBIFLEX 35M" is a multi-block polymer in which a plurality of hard segments of aromatic polyester (polybutylene terephthalate) and soft segments of polyether (polytetramethylene glycol) are alternately linked, and has a molecular weight of 100,000-150,000,
It has a softening point of 175 ° C. and a JIS A hardness of 93.

[Production of Composite Member] A heat-resistant transparent ABS resin “JSR-ABS 58 (manufactured by Japan Synthetic Rubber Co., Ltd.)” was used to produce a sheet of 100 mm × 75 mm × 0.5 mm. On one surface of this sheet, a urethane thermosetting ink (standard curing temperature 80 ° C.) is used to perform blank printing by a screen printing machine, and thereafter, a curing treatment is performed at 70 ° C. for 3 hours to obtain a desired pressing force. An intermediate layer material was formed according to the arrangement of the pressed portions of the button member to obtain a composite member having the configuration shown in FIG. The adhesion area of the intermediate layer material was about 95% of the area of the upper surface of each pressed portion of the push button member, and the thickness thereof was 15 μm.

[Injection Molding] After the prepared thermoplastic polyester elastomer material is sufficiently dried, the composite member is formed into an insert receiving plate and a movable side of the mold X in an injection molding machine equipped with the mold X using the material. The push button member provided with the key top member on the pressed portion was obtained by disposing it between the mold plate and the molding plate under the conditions of a molding temperature of 210 ° C. and a mold cooling time of 20 seconds.

A contact member was formed by printing carbon black type conductive ink on the bottom surface of the pressed portion of the obtained push button member by screen printing and then leaving it at 80 ° C. for 200 minutes. With this push button member,
A keyboard switch having the structure shown in FIG. 1 was manufactured.

<Example 2> A keyboard switch was manufactured in the same manner as in Example 1 except that a sheet of 100 mm x 75 mm x 0.25 mm was prepared using a polycarbonate resin, and a composite member was obtained using this sheet. .

<Example 3> A keyboard switch was manufactured in the same manner as in Example 1 except for the following points. [Production of Insert Injection Mold] According to the structure shown in FIG. 10, S55C-based general metallic steel is used as the material of the mold, and the average porosity is 25 as the material of the ventilation member.
%, The average pore diameter is 7 μm, and the hardness is HRC40, a porous metal “Pocerax II PM40 (manufactured by Shinto Kogyo Co., Ltd.)” is used, and the thickness of the portion corresponding to the deformable portion of the cavity is 0.13 mm, and the portion corresponding to the base portion. A mold Y was manufactured in which the angle of the portion corresponding to the deformable portion was 51 degrees.

[Production of Composite Member] Using polycarbonate resin, a long sheet having a thickness of 0.15 mm and a width of 60 mm was produced. One side of this sheet is blank printed by a screen printing machine using a urethane thermosetting ink (standard curing temperature 80 ° C.), and then passed through a drying oven set at 80 ° C. for 30 minutes to stay. By performing the curing process, a group of intermediate layer materials arranged according to the arrangement of the pressed portions of the target push button member are formed at a constant interval in the length direction of the sheet, A composite member continuous body having the structure shown in was obtained. The adhesion area of the intermediate layer material is about 95 of the area of the upper surface of each pressed portion of the push button member.
%, And the thickness was 15 μm.

[Injection Molding] In an injection molding machine equipped with a mold Y, as shown in FIG. 10, the composite member continuum is used as an unwinding roll, and is moved by a winding roll to move each member in the composite member continuum. A push button member having a key top member on the pressed portion was obtained in the same manner as in Example 1 except that the composite member was arranged between the insert receiving plate of the mold Y and the movable side mold plate.

<Example 4> A keyboard switch was manufactured in the same manner as in Example 1 except for the following points. [Production of Insert Injection Mold] According to the configuration shown in FIG. 12, S55C general metal steel is used as the material of the mold, and the average porosity of 25 is used as the material of the ventilation member.
%, The average pore diameter is 7 μm, and the hardness is HRC40, a porous metal “Pocerax II PM40 (manufactured by Shinto Kogyo Co., Ltd.)” is used, and the thickness of the portion corresponding to the deformable portion of the cavity is 0.13 mm, and the portion corresponding to the base portion. A mold Z was produced in which the angle of the portion corresponding to the deformable portion with respect to was 45 degrees.

[Manufacture of Composite Member] With a 50T injection molding machine (manufactured by Japan Steel Works), a polycarbonate resin material was injected and injected into the cavity of the mold with the mold opened at intervals of 0.2 mm. After that, by performing mold clamping with the maximum mold clamping pressure, a plurality of keytop forming portions protruding in a spherical shape according to the arrangement of the pressed portions of the target push button member and the periphery of each of the keytop forming portions are formed. A sheet having the structure shown in FIG. 11 having the cut portion was prepared. On one surface of the key-top forming part of this sheet, a urethane thermosetting ink (standard curing temperature of 80 ° C.) was used to perform hollow printing using a screen printing machine, and then 70
The intermediate layer material was formed by carrying out a curing treatment at 3 ° C. for 3 hours to obtain a composite member having the configuration shown in FIG. In the above, the maximum thickness of the key top forming part is 0.8 mm, the thickness of the cutting part is 0.4 mm, and the width of the cutting part is 1.0.
In addition, the adhesion area of the intermediate layer material was about 95% of the area of the upper surface of the pressed portion of the push button member, and the thickness thereof was 15 μm.

[Injection Molding] In an injection molding machine equipped with the mold Z, the procedure of Example 1 was repeated except that the composite member was arranged between the insert receiving plate of the mold Z and the movable side mold plate. A push button member having a key top member provided on the pressed portion was obtained.

<Comparative Example 1> In Example 1, the sheet was placed between the insert receiving plate of the mold A and the movable side mold plate without printing the urethane thermosetting ink, and the sheet was placed on the pressed portion. A keyboard switch was obtained in the same manner except that a push button member formed so as to be in direct contact with the key top member was obtained. In this keyboard switch, the key top member is peeled from the pressed portion of the push button member with a slight peeling force.

When the light emitting member of the keyboard switch obtained in Examples 1 to 4 was turned on, it was confirmed that the pressed portion of the push button member had sufficient translucency.

<Experimental Example> The following items were evaluated for the keyboard switches obtained in Examples 1 to 4. [Shooting operation feeling] The pressing load of the push button member of the keyboard switch was measured. Here, the pressing load and the click rate are measured as follows. Pressing load The maximum operating load, which is measured until the pressed portion of the push button member installed on the substrate is pressed at a constant speed and the bottom surface of the pressed portion contacts the substrate, is called the pressing load. In this experimental example, the pressing load when pressing at a speed of 2 mm / sec was obtained. Click rate When the pressed portion of the push button member is pressed, a relationship as shown in FIG. 13 is obtained between the measured operating load and the stroke. In this figure, that CTR the ratio of the difference of the operation load P ₂ at the operating load P ₁ and a minimum peak for operating the load P ₁ at the maximum peak. That is, the click rate α is α = (P ₁ −P ₂ ) / P ₁ × 10
It is calculated as 0 (%). In this embodiment, 2 mm
The click rate when pressed at a speed of / sec was obtained.
In the above, when the pressing load is 300 g or less and the click rate is 30% or more, the feeling of switching operation is good. [Durability] In addition, a keystroke test was conducted 1 million times to check for peeling of the keytop member, and the pressing load and electrical resistance of the keyboard switch after the keystroke test were measured and compared with the values before the keystroke test. did. The electrical resistance is
Using a comb-shaped electrode (electrode width 0.3 mm, interval 0.3 mm), measurement was performed while pressing the pressed portion with a load of 200 g. The results are shown in Table 1.

[0119]

[Table 1]

As is clear from Table 1, the keyboard switches obtained in Examples 1 to 4 are excellent in switching operation feeling, and the key top member is not a push button member even after 1 million keystrokes. It did not separate from the portion to be pressed, had small changes in pressing load and electric resistance, and had high durability.

[0121]

According to the manufacturing method of the present invention, the heat of the injected molten thermoplastic polyester elastomer material causes the thermoplastic polyester elastomer material to adhere to the intermediate layer material formed on one surface of the composite member. Since the push button member is molded in this state, both the molding of the push button member and the integration of the pressed portion of the push button member and the key top member can be performed in a single process. Therefore, the work of assembling the key top member becomes unnecessary. Therefore, the keyboard switch in which the key top member is provided on the pressed portion of the push button member can be easily manufactured by a simple process.

The keyboard switch obtained by the manufacturing method of the present invention has the key top formed by the intermediate layer interposed between the key top member made of the transparent resin and the pressed portion of the push button member made of the thermoplastic polyester elastomer material. Since the member and the pressed portion of the push button member are sufficiently joined and integrated, the minimum thickness required for the key top member can be made small, and as a result, the entire keyboard switch Since the thickness can be made sufficiently small, it becomes possible to make the device thin, and it can be suitably used for a portable device or the like. Moreover, since the display portion for identifying the pressed portion of the push button member is formed by this intermediate layer, the display portion is not worn, and therefore the function as the display portion is diminished. Can be prevented.

Further, according to the manufacturing method of the first aspect, since the mold in which the ejector pin is provided at the position corresponding to the pressed portion of the push button member in the cavity is used, the ejector pin is moved forward. As a result, the molded push button member is pushed out at the pressed portion, so that the entire push button member can be reliably released from the mold, thereby preventing damage and deformation of the deformable portion at the time of mold release. You can

According to the manufacturing method of the second aspect, since the mold is provided with the air passage communicating with the position corresponding to the pressed portion of the push button member in the cavity, the compression is performed via this air passage. By sending air,
Since the molded push button member is pushed out at the pressed portion, the entire push button member can be reliably released from the mold, whereby damage and deformation of the deformable portion at the time of release can be prevented.

According to the composite member for manufacturing a keyboard switch of the present invention, the cutting portion having a specific thickness smaller than the portion serving as the key top member is formed around the portion serving as the key top member. In the molding step, the portion that will be the key top member can be reliably cut and separated from the other portions.

Further, in the method described in claim 1,
At the tip of the ejector pin, it is possible to use an insert molding die having a structure in which a reduced pressure is applied at the molding position and the reduced pressure is released at the release position. In this case, it is possible to use an insert molding die in which a ventilation member is provided at the tip of the ejector pin.

[Brief description of drawings]

FIG. 1 is an explanatory sectional view showing a configuration of an example of a keyboard switch obtained by a manufacturing method of the present invention.

FIG. 2 is an explanatory diagram showing an example of a composite member used in the manufacturing method of the present invention.

FIG. 3 is an explanatory cross-sectional view showing a partial configuration of an example of an insert injection molding die used in the manufacturing method of the present invention.

FIG. 4 is an explanatory cross-sectional view showing a state where the insert injection molding die having the configuration shown in FIG. 3 is closed.

5 is an explanatory cross-sectional view showing a state where an ejector pin of the insert injection molding die having the configuration shown in FIG. 3 is advanced.

FIG. 6A is an explanatory view showing a state in which the composite member is arranged in the insert injection molding die, and FIG. 6B shows a state in which the composite member is cut and separated in the insert injection molding die. FIG.

FIG. 7C is an explanatory view showing a state where the thermoplastic polyester elastomer material is injected into the cavity, and FIG. 7D is an explanatory view showing a state where the molded product is released from the mold by the ejector pin.

FIG. 8 is an explanatory sectional view showing a partial configuration of another example of the insert injection molding die used in the manufacturing method of the present invention.

FIG. 9 is an explanatory diagram showing an example of a composite member continuous body that can be used in the present invention.

10 is an explanatory diagram showing an outline of a manufacturing system in the case of performing insert injection molding using the composite member continuous body shown in FIG.

FIG. 11 is an explanatory sectional view showing an example of a composite member for manufacturing a keyboard switch of the present invention.

FIG. 12 is an explanatory sectional view showing a part of the configuration of still another example of the insert injection molding die used in the manufacturing method of the present invention.

FIG. 13 is a characteristic curve diagram showing a relationship between an operating load and a stroke when the pressed portion is pressed.

FIG. 14 is an explanatory sectional view showing an example of a conventional keyboard switch.

FIG. 15 is an explanatory sectional view showing an example of a keyboard switch including a conventional key top member.

[Explanation of symbols]

10,85 Substrate 11,86 Conductive terminal part 15,87 Cover member 16,88 Opening 18 Light emitting member 20,80 Push button member 21,81 Pressed part 22,82 Deformable part 23,83 Base part 25,84 For short circuit Contact member 30, 90 Key top member 31, 35 Composite member 32 Composite member continuous body 33 Unwinding roll 34 Winding roll 36 Key top forming part 37 Cutting part 40 Intermediate layer 41 Intermediate layer material 50 Fixed side mold 51 Fixed side Receiving plate 52 Fixed-side mold plate 60, 60a, 60b Movable-side mold 61 Movable-side mold plate 62, 71, 76 Insert receiving plate 63, 72 Cutting part 64, 73 Storage groove 65 Decompression passage 66 Opening passage 67, 77 Ejector pin 68,74 Vent member 69,69a
Vent hole 70, 77b Extrusion plate 75 Air passage 91 Head portion 92 Collar portion C Cavity G Gate R Runner K Sprue D Extension space S, S1, S2
Transparent resin sheet

Continuation of the front page (72) Inventor Shirou Toyoshima 26 Showa Onuma, Ibu-cho, Minami-Saitama-gun, Saitama Prefecture

Claims (3)

[Claims] 1. A push formed by molding a thermoplastic polyester elastomer material, wherein a pressed portion is integrally formed on a base portion through a deformable portion having a small wall thickness extending outward from an outer peripheral edge thereof. A button member, a key top member made of a transparent resin provided on the pressed portion of the push button member, and a heat provided between the pressed portion of the push button member and the key top member. A keyboard having an intermediate layer that forms a display portion formed by curing a curable ink or a thermosetting paint, and the pressed portion of the push button member and the key top member are joined by the intermediate layer. A method of manufacturing a switch using a mold for insert injection molding, comprising a transparent resin sheet and an intermediate layer material formed of thermosetting ink or thermosetting paint. The material is placed in the insert injection molding die, and then the insert injection molding die is clamped to cut the intermediate layer material and the part to be the key top member related thereto from the composite member. While separating, the outer surface of the intermediate layer material is exposed to the cavity, and by injecting the melted thermoplastic polyester elastomer material into the cavity of the insert injection molding die, the pressed portion forms the intermediate layer. There is a molding step of molding the push button member in a state of being joined to the key top member via the ejector pin at a position corresponding to the pressed portion of the push button member in the cavity as the insert injection mold. By using the provided one, the ejector pin is pushed out, and the molded push button member is Method for producing a keyboard switch, characterized in that to the mold. 2. A method of manufacturing a keyboard switch having the structure according to claim 1 using an insert injection molding die, comprising the molding step according to claim 1, As the mold, one having an air passage communicating with a position corresponding to the pressed portion of the push button member in the cavity is used, and compressed air is sent through this air passage to form a molded push button member. A method of manufacturing a keyboard switch, characterized by releasing the mold. 3. A keyboard switch manufacturing composite member used in a method of manufacturing a keyboard switch having the molding step according to claim 1, comprising a transparent resin sheet and a portion of the transparent resin sheet which is a key top member. A cutting portion having a thickness smaller than the thickness of the portion to be the key top member of the transparent resin sheet is formed around the portion to be the key top member of the transparent resin sheet. A composite member for manufacturing a keyboard switch, wherein the thickness of the use portion is 1 mm or less.