Improvements in membrane switch graphic assemblies

Abstract

 A membrane switch graphic assembly comprising superimposed outer and inner layers of flexible material is disclosed. The outer layer (1) is constituted by a transparent or translucent plastics material, and the inner layer (2) comprises paper. An intermediate layer (3) of clear adhesive is situated at the interface of the two layers. Printed material applied to the outer face of the paper at the interface with the intermediate layer is visible through the outer layer (1).

Description

[0001] This invention relates to improvements in membrane switch graphic assemblies of the kind comprising a flexible membrane which is adapted to enclose a switch operating member through which the switch is adapted to be operated by finger pressure, or other mechanical means.

[0002] Known switch graphic assemblies of the kind set forth comprise plastic films usually of polyester or polycarbonate materials having a gloss and textured outer front face and an underside inner face on which graphics can be printed by using a screen printing technique.

[0003] According to our invention a membrane switch graphic assembly comprises superimposed outer and inner layers of flexible material, the outer layer being constituted by a transparent or translucent plastics material, the inner layer comprising paper, with an intermediate layer of clear adhesive situated at the interface of the two layers, whereby printed material applied to the outer face of the paper at the interface with the intermediate layer is visible through the outer layer.

[0004] Providing printed material on paper has the advantage that the screen printing step onto the plastics material can be eliminated.

[0005] The outer layer may comprise a transparent or translucent plastics material of which the outer face may be of embossed configuration.

[0006] The underside of the paper layer may be secured, for example by adhesive, to a housing or circuit assembly or the like through which the switch operating member can be operated.

[0007] Conductive ink can be printed on the underside of the graphic assembly, onto the paper, thereby forming an integral and active part of the circuit assembly.

[0008] One embodiment of our invention is illustrated in the accompanying drawing in which the single Figure is a section through a membrane switch graphic assembly.

[0009] The membrane switch graphic assembly comprises a flexible outer layer 1 of transparent or translucent plastics material suitably a polyester or a polycarbonate. An inner layer 2 comprises paper. The two layers are superimposed upon each other and a layer 3 of clear adhesive provides a permanent connection between the two materials at the interface of the two layers.

[0010] Printed matter on the outer face of the paper layer 2 is externally visible through the clear adhesive 3 and the outer layer 1.

[0011] The outer face of the layer 1 of plastics material is embossed.

[0012] When the graphic assembly is installed in a component assembly with the panel enclosing a switch operating member, for example a push button switch, the graphic assembly may be attached by adhesive 4 to the housing or circuit assembly through which the member can be operated.

[0013] Our membrane switch graphic assembly is simple to manufacture and construct. No sophisticated printing techniques are required.

Claims

1. A membrane switch graphic assembly comprising superimposed outer and inner layers of flexible material, the outer layer (1) being constituted by a transparent or translucent plastics material,
   characterised in that:
   the inner layer (2) comprises paper, and
   an intermediate layer (3) of clear adhesive is situated at the interface of the two layers,
   whereby printed material applied to the outer face of the paper at the interface with the intermediate layer (3) is visible through the outer layer (1).

2. A membrane switch graphic assembly according to claim 1, characterised in that the outer face of the outer layer (1) is of embossed configuration.

3. A membrane switch graphic assembly according to claim 1 or claim 2, characterised in that the underside of the paper layer (2) is secured to a housing or circuit assembly through which a switch operating member can be operated.

4. A membrane switch graphic assembly according to claim 3, characterised in that the underside of the paper layer (2) is secured by adhesive (4) to the housing or circuit assembly.

5. A membrane switch graphic assembly according to claims 1 to 3, characterised in that conductive ink is printed onto the underside of the paper layer (2), thereby forming an integral and active part of the circuit assembly.

Drawing