JP2012129073A - Contact substrate, manufacturing method thereof, and input device using contact substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact substrate which can manufacture a code pattern without specially using a metal mold and can flow a large current therethrough, and to provide a method of manufacturing the contact substrate, and an input device using the contact substrate.SOLUTION: A contact substrate 1 having an insulating pattern 4 and a conductive pattern 5 on a sliding surface 1a includes: a conductive substrate 2; and an insulating layer 3 forming the insulating pattern 4 on a surface 2a of the conductive substrate 2 by a thermal transfer printer. The contact substrate 1 can be manufactured which can flow the large current therethrough without using the metal mold.

Description

  The present invention relates to a contact board that can be manufactured without using a metal mold for forming a code pattern and can flow a large current.

  There is insert molding as a conventional technique related to the manufacture of a contact board (code board). However, in the case of insert molding, for each code pattern, a pattern punching die and an outer shape injection molding die with different pin positions to hold the insert metal on the surface of the part are required, and lead time (LT) However, there was a problem that the mold cost was long.

  In the method of manufacturing a contact board using a printed circuit board instead of insert molding, there has been a problem that the development and peeling process of the photoresist and the etching process of the copper foil are required, and the complexity of the manufacturing process and the manufacturing cost are increased.

  The invention described in Patent Document 1 below discloses a method for manufacturing a printed circuit board in which a conductive pattern is thermally transferred and printed on the surface of an insulating substrate made of, for example, a polyimide resin.

JP-A 64-8700

  However, as described in Patent Document 1, in the method of forming a conductive pattern on an insulating substrate, there is a problem that the conduction resistance of the circuit becomes high, the current value is limited, and a large current cannot flow. there were.

  Therefore, the present invention is to solve the above-described conventional problems, and in particular, a contact board that can be manufactured without using a mold for manufacturing a code pattern and can flow a large current, a manufacturing method thereof, and a contact board An object of the present invention is to provide an input device using the.

The present invention is a contact board having an insulating pattern and a conductive pattern on a sliding surface,
It has an electroconductive board | substrate, and the insulating layer formed in the said insulating pattern by the thermal transfer printer on the surface of the said electroconductive board | substrate.

  An input device according to the present invention includes the contact board according to the present invention and a slider that slides on a sliding surface. In this invention, it can be set as the structure which a common slider slides on the back surface side on the opposite side with respect to the surface side in which the said insulating layer of the said conductive substrate was formed.

Further, the present invention is a method of manufacturing a contact board having an insulating pattern and a conductive pattern on a sliding surface,
It is characterized in that the insulating layer comprising the insulating pattern is thermally transferred and printed on the surface of the conductive substrate using a thermal transfer printer.

  In the present invention, a plating layer can be applied to the surface of the conductive substrate exposed at the position of the conductive pattern to reduce the step between the conductive pattern and the insulating pattern. In the present invention, the position of the conductive pattern can be reduced. It is also possible to deform the conductive substrate by pressing in the direction from the rear surface side to the front surface side where the insulating layer is formed.

  According to the present invention, it is possible to manufacture a contact board capable of flowing a large current without using a mold for forming a code pattern.

That is, in the present invention, the insulating layer is patterned on the conductive substrate by the thermal transfer printer. Conversely, in the embodiment in which the conductive layer is patterned on the insulating substrate by the thermal transfer printer, the volume resistivity value is approximately 10 ⁻⁴ to 10 ^−5. A high Ag paste such as Ω · cm must be used, and the film thickness is as thin as about 10 μm. Further, the increase in circuit length due to patterning increases the conduction resistance value, which limits the current used. In addition, Ag powder in Ag paste is spread and soft, and if it is filled with particles harder than Ag powder such as nickel or alumina to increase the hardness of the conductive layer, the Ag powder has to be reduced accordingly. Has the problem of deteriorating.

  Therefore, a contact substrate capable of flowing a large current without using a mold for forming the code pattern can be manufactured by adopting a configuration in which the insulating pattern is thermally transferred onto the surface of the conductive substrate as in the present invention.

  In the present invention, the thermal transfer printer is used to form the insulating layer, but there are the following merits as compared with the method using screen printing or inkjet. That is, by using a thermal transfer printer as in the present invention, a fine pattern is possible as compared with screen printing, surface roughness is reduced, and variations in in-plane film thickness can be suppressed. Furthermore, since no screen mask is required, the pattern of the insulating pattern can be easily changed. Moreover, compared with an inkjet, a film thickness can be taken out and arbitrary fillers (particles) on the order of μm to submicron can be included. For this reason, the wear resistance of the insulating layer is improved, and even if the insulating layer is worn, the life until the insulation is broken can be extended. In addition, the manufacturing process can be facilitated and the pattern change of the insulating pattern can be further facilitated at a lower equipment cost than a dry film or a liquid photoresist. As described above, the thickness of the insulating layer, surface smoothness, and withstand voltage can be improved at low cost, and a contact substrate having excellent sliding characteristics can be obtained.

  According to the present invention, it is possible to manufacture a contact board capable of flowing a large current without using a mold for forming a code pattern.

FIG. 1A is a longitudinal sectional view of a contact board (code plate) in the present embodiment, and FIG. 1B is a partial longitudinal sectional view of an input device using the contact board shown in FIG. It is a longitudinal cross-sectional view of the contact substrate (code board) in another embodiment.

  FIG. 1A is a longitudinal sectional view of a contact board (code plate) in the present embodiment, and FIG. 1B is a partial longitudinal sectional view of an input device using the contact board shown in FIG.

  In the contact substrate 1 in this embodiment, the insulating pattern 4 and the conductive pattern 5 appear on the sliding surface 1a.

  As shown in FIG. 1A, the contact substrate 1 has a conductive substrate 2 such as a metal strip, and an insulating layer 3 formed on the insulating pattern 4 on the surface 2a of the conductive substrate 2 by a thermal transfer printer. Configured.

  The conductive substrate 2 is preferably a copper alloy such as brass or phosphor bronze. The insulating layer 3 has a resin and a filler and is patterned. The resin may be a thermoplastic resin or a thermosetting resin. As the thermoplastic resin, a crystalline resin has a high melting point (Tm), or an amorphous resin has a high glass transition point and is excellent in heat resistance. A thermoplastic polyimide or the like is preferable. Can be used. As the thermosetting resin, B-stage thermosetting resin can be preferably used. Specifically, thermosetting acrylic resin, melamine resin, urethane resin, phenol resin, epoxy resin, bismaleide triazine resin, diallyl phthalate resin. Etc.

  It is also preferable to use a blend resin of an epoxy resin and a bismaleimide triazine resin (BT resin; registered trademark).

  As the filler, in order to reduce the wear of the slider (symbol 8 in FIG. 1B), a spherical one is preferably applied as much as possible. In the present embodiment, the insulating layer 3 is thermally transferred and printed on the surface 2a of the conductive substrate 2 using a thermal transfer printer. The filler contains an appropriate amount of particles having a predetermined hardness from the μm order to the submicron order. Can be made. As the filler, spherical glass fine particles (Sunsphere; registered trademark), carbon beads (Nika beads; registered trademark), boron nitride, titanium oxide, and the like can be appropriately selected.

  Further, in order to improve the adhesion to the conductive substrate 2, a coupling agent, a sulfur-containing resin (thiocol; registered trademark) or the like may be included as an additive.

  The film thickness of the insulating layer 3 can be adjusted within a range of several μm to several tens of μm. Further, the thermal transfer process of the insulating layer 3 may be performed once or a plurality of times in order to increase the film thickness.

As shown in FIG. 1A, a plating layer 6 is formed on the surface 2a (position of the conductive pattern 5) of the conductive substrate 2 that is exposed without the insulating layer 3 formed. The plating layer 6 is formed by, for example, electroplating a metal for electrical contact on a base plating layer (not shown). At this time, the plating layer 6 can be formed by growing the plating on the exposed surface 2a of the conductive substrate 2 using the conductive substrate 2 as an electrode in electroplating and the insulating layer 3 as a mask. It is also possible to form the plating layer 6 by electroless plating. As shown in FIG. 1A, the plating layer 7 is also formed on the back surface 2 b of the conductive substrate 2.
The plating layer 6 may be of any material, and may be a single layer or a laminated structure having different materials.

  The base plating (not shown) of the plating layer 6 includes single metal plating such as Cu plating and Ni plating, nickel alloy plating such as Ni-P and Ni-W, PTFE (Teflon; registered trademark) powder and carbon nanotubes in the plating film. Dispersion plating containing etc. may be sufficient.

  The surface plating of the plating layer 6 may be not only Au, Ag, and Pd, which have high corrosion resistance suitable for electrical contacts, but also Cu, Sn, etc., which easily breaks the oxide film due to a large current.

  By forming the plating layer 6, it is possible to reduce the step between the insulating layer 3 and the conductive substrate 2, and it is possible to cover minute ground stains that occur during thermal transfer of the insulating layer. . The term “soil stain” as used herein refers to an insulator transferred to an unintended location or an insulator attached from a thermal transfer film or the like when forming an insulating pattern.

  As shown in FIG. 1B, the slider 8 is in contact with the sliding surface 1 a of the contact substrate 1 (code plate), and the common slider 12 is in contact with the back surface 1 b of the contact substrate 1.

  One of the slider and the contact board is the moving side and the other is the fixed side. For example, the sliders 8 and 12 are the fixed side, and the contact board 1 moves in the X direction in FIG. Thereby, the slider 8 slides alternately between the conductive pattern 5 (the surface of the plating layer 6) and the insulating pattern 4 (the surface of the insulating layer 3) appearing on the sliding surface 1a of the contact substrate 1, The common slider 12 slides on the surface of the plating layer 7 located on the back surface 1 b of the contact board 1.

  When a pull-up resistor is connected to the slider 8 and a predetermined voltage is applied, when the slider 8 slides on the conductive pattern 5 of the contact substrate 1, the slider 8 and the common slider 12 Are electrically connected and an ON signal is output. On the other hand, when the slider 8 slides on the insulating pattern 4 of the contact board 1, the slider 8 and the common slider 12 are electrically disconnected. And an OFF signal is output. Then, when the contact substrate 1 moves in the X direction in FIG. 1B, the on signal and the off signal are alternately repeated, and a pulse signal is output.

  For example, the above pulse signal is referred to as an A-phase pulse signal. Although not shown in the drawing, the position of the conductive pattern (insulating pattern) in the X direction is different (shifted) from that in FIG. A B-phase slider different from the slider 8 (A-phase slider) shown in FIG. 1B is provided on the conductive pattern and the insulating pattern in the B-phase region. By sliding relative to the contact board 1 together with 12, the B-phase pulse signal can be obtained by electrical connection / disconnection between the B-phase slider and the common slider 12. At this time, the B-phase pulse signal can have a different phase from the A-phase pulse signal. Therefore, by obtaining the A-phase pulse signal and the B-phase pulse signal, not only the moving amount (speed) of the contact substrate 1 but also the moving direction can be known.

  In FIG. 1 (b), the contact substrate 1 moves linearly in the X direction. However, the contact substrate 1 rotates like a rotary switch, and a conductive pattern and an insulating pattern are concentrically arranged from the rotation center. It is also possible to adopt a configuration in which are alternately arranged.

  In FIG. 1B, the back surface 1b of the contact board 1 can be used as a common region, and the number of sliders arranged concentrically can be reduced, so that the outer dimensions of the product can be reduced. .

  As a manufacturing method of the contact substrate 1 in the present embodiment, the insulating layer 3 composed of the insulating pattern 4 is thermally transferred and printed on the surface 2a of the conductive substrate 2 using a thermal transfer printer. Subsequently, the surface 2a of the conductive substrate 2 exposed at the position of the conductive pattern 5 is plated using the insulating layer 3 as a mask.

  The only method for manufacturing the contact substrate 1 in this embodiment is to form an insulating pattern on the conductive substrate or to form a conductive pattern on the insulating substrate.

  In the form in which the conductive pattern is formed on the insulating substrate, it is necessary that the conductive pattern is conductive, satisfies the condition that it can withstand adhesion to the insulating substrate and sliding wear.

  However, in the form in which the conductive pattern is formed on the insulating substrate, the conductive resistance value of the conductive pattern made of Ag paste or the like becomes high, and the working current is limited. Moreover, it is difficult to put Ag powder and adjust the hardness appropriately. Further, when the conductive pattern is formed, the insulating pattern portion becomes a concave portion, and it is difficult to fill this step. In particular, when the space between the conductive patterns is narrow, it is difficult to apply and print the insulating material. Therefore, it is difficult to satisfy all the conditions required for the conductive pattern. On the other hand, in the embodiment in which the insulating pattern is formed on the conductive substrate, the conductivity is appropriately ensured by the conductive substrate 2 and the plating layers 6 and 7 (in the embodiment in which a plating layer to be described later is not formed). Therefore, the insulating layer 3 only needs to satisfy the conditions that can withstand adhesion to the conductive substrate and sliding wear, and it can be easily and appropriately adjusted according to the material and content of the resin and filler constituting the insulating layer 3. In other words, the degree of freedom of adjustment can be increased as compared with the case where the conductive pattern is formed on the insulating substrate. Even if the space between the conductive patterns is narrow, if the plating solution is touched, the plating film is deposited and the step difference from the insulating pattern can be reduced. Further, unlike the insert terminal in insert molding, the conductive substrate is in the form of a sheet, so that the in-plane potential difference is small and the variation in the thickness of the plating film can be reduced. Note that the surface of the insulating layer 3 can be formed smoothly on a smooth surface by pressurization during thermal transfer by a thermal transfer printer.

  In this embodiment, since the insulating layer 3 is formed by patterning on the surface 2a of the conductive substrate 2 by a thermal transfer printer, a mold is not required for forming the code pattern as in insert molding.

  As described above, according to the present embodiment, it is possible to manufacture the contact board 1 capable of flowing a large current without using a mold.

  By the way, although the thermal transfer printer was used for formation of the insulating layer 3 in this embodiment, there exist the following merits compared with the method using screen printing or an inkjet. That is, by using a thermal transfer printer as in the present embodiment, a fine pattern is possible as compared with screen printing, the surface roughness is reduced, variation in in-plane film thickness can be suppressed, and the insulating pattern 4 The pattern can be changed easily. Moreover, compared with an inkjet, a film thickness can be taken out and arbitrary fillers (particles) on the order of μm to submicron can be included. For this reason, the wear resistance of the insulating layer is improved, and even if it is worn, the life until the insulation is broken can be extended. In addition, the manufacturing process can be simplified and the pattern change of the insulating pattern 4 can be further facilitated at a lower equipment cost than a dry film or a liquid photoresist. As described above, it is possible to improve the film thickness control, surface smoothness, and withstand voltage of the insulating layer 3 at low cost, and it is possible to manufacture the contact substrate 1 having excellent sliding characteristics.

  As shown in FIG. 1, by forming the plating layer 6 on the surface 2a of the conductive substrate 2 exposed at the position of the conductive pattern 5, the step between the insulating layer 3 and the conductive substrate 2 can be reduced. Further, although it can be covered with soil, a form without the plating layer 6 is also one form of this embodiment as shown in FIG.

  Alternatively, the conductive substrate 9 in FIG. 2A is made of a material or film thickness that is easily deformed, such as a metal foil, and the conductive substrate 9 at the position of the conductive pattern 5 is placed on the back surface 9b as shown by the arrow in FIG. It can also be deformed by pressing (hot pressing, elastic pressing, vacuum pressing, etc.) from the side toward the surface 9a on which the insulating layer 3 is formed. FIG. 9B is a view after the conductive substrate 9 is deformed.

  Further, as shown in FIG. 2C, thin plating layers 10 and 11 may be formed on the front surface 9 a of the deformed conductive substrate 9 and the back surface 9 b of the conductive substrate 9 positioned in the conductive pattern 5. The plating layers 10 and 11 can be formed before the conductive substrate 9 is deformed, that is, at the time of FIG. 2A, and then the conductive substrate 9 can be deformed as shown in FIG. 2B. .

  2B and 2C, the step between the conductive pattern and the insulating pattern can be reduced.

DESCRIPTION OF SYMBOLS 1 Contact board 1a Sliding surface 2, 9 Conductive board 3 Insulating layer 4 Insulating pattern 5 Conductive pattern 6, 7, 10, 11 Plating layer 8 Slider 12 Common slider

Claims (8)

A contact board having an insulating pattern and a conductive pattern on a sliding surface,
A contact substrate comprising: a conductive substrate; and an insulating layer formed in the insulating pattern on a surface of the conductive substrate by a thermal transfer printer.   The contact board according to claim 1, wherein a plating layer is formed at a position of the conductive pattern on the surface of the conductive board.   The contact substrate according to claim 1, wherein the conductive substrate at the position of the conductive pattern is deformed from a back surface side toward a front surface side on which the insulating layer is formed.   An input device comprising: the contact board according to claim 1; and a slider that slides on the sliding surface.   The input device according to claim 4, wherein a common slider slides on the back side opposite to the surface side on which the insulating layer of the conductive substrate is formed. A method of manufacturing a contact board having an insulating pattern and a conductive pattern on a sliding surface,
A method of manufacturing a contact substrate, comprising: thermally transferring and printing an insulating layer comprising the insulating pattern on a surface of a conductive substrate using a thermal transfer printer.   The method for manufacturing a contact substrate according to claim 6, wherein the surface of the conductive substrate exposed at the position of the conductive pattern is plated.   The method for manufacturing a contact substrate according to claim 6 or 7, wherein the conductive substrate at the position of the conductive pattern is deformed by pressing from the back surface side toward the front surface side on which the insulating layer is formed.

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