WO2017018986A1

WO2017018986A1 - Sealed conductive traces

Info

Publication number: WO2017018986A1
Application number: PCT/US2015/041964
Authority: WO
Inventors: Luis C. Armendariz; Hung-Ming Chen; Gary CHVATAL
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2015-07-24
Filing date: 2015-07-24
Publication date: 2017-02-02

Abstract

Example implementations relate to sealed conductive traces. In one example, a keyboard membrane including sealed conductive traces includes a first circuit including a first conductive trace and a first key contact of the keyboard membrane, where the first conductive trace is coupled to the key contact, a second circuit including a second conductive trace and a second key contact of the keyboard membrane, where the second conductive trace is coupled to the second key contact, and a layer of ultraviolet (UV) curable material overlaying a portion of each of the first conductive trace and the second conductive trace to seal the first conductive trace and the second conductive trace.

Description

SEALED CONDUCTIVE TRACES

Background

[0001] Keyboards are utilized in a variety of applications. For example, keyboards may be utilized as an input device to provide letters, numbers and/or characters to a computer, among other possibilities. Ensuring that a keyboard operates as intended may be desirable.

Brief Description of the Drawings

[0002] Figure 1 illustrates a profile view of an example of a keyboard membrane including sealed conductive traces according to the disclosure.

[0003] Figure 2 illustrates a top view of an example of a portion of a keyboard membrane including sealed conductive traces according to the disclosure.

[0004] Figure 3 illustrates a flow diagram of an example of a method of manufacture of keyboard membranes including sealed conductive traces according to the disclosure.

Detailed Description

[0005] During an operational lifetime a keyboard may be subjected to

environmental conditions such as humidity and/or liquid (e.g., liquids spilled on a surface of the keyboard), among other environmental conditions, that may cause the keyboard to experience temporary and/or permanent damage. As a result, the keyboard may not function as intended. For example, a particular key (e.g., a spacebar) on the keyboard may not produce a desired output (e.g., a space). As such, ensuring that a keyboard operates as intended may be desirable

[0006] Examples of the disclosure include keyboard membranes including sealed conductive traces and methods of manufacturing the same. Keyboard membranes as used herein refer to those suitable in a keyboard. As used herein, sealed conductive traces refer a conductive trace (e.g., a silver conductive trace) coupled to contact (e.g., a key contact) included in a circuit such as a circuit included in a keyboard membrane where the conductive trace is at least partially sealed from environmental conditions such as humidity and/or liquids, among other environmental conditions by a layer of ultraviolet (UV) curable material. That is, while described herein with respect to keyboard membranes, sealed conductive traces can be utilized a variety of other applications and/or devices that employ a conductive trace or similar electrical component.

[0007] A keyboard membrane including sealed conductive traces can, for example, include a first circuit including a first conductive trace and a first key contact of the keyboard membrane, where the first conductive trace is coupled to the key contact, a second circuit including a second conductive trace and a second key contact of the keyboard membrane, where the second conductive trace is coupled to the second key contact, and a layer of UV curable material overlaying a portion of each of the first conductive trace and the second conductive trace to seal the first conductive trace and the second conductive trace. Desirably, keyboard membranes including sealed conductive traces, as described herein, provide protection from environmental conditions such as humidity and/or liquids while retaining desired functionality of the keyboard membrane (e.g., having a desired force to fire, etc.), in contrast to other keyboard membranes that do not include sealed conductive traces and therefore may not function as intended when and/or following being exposed to various environmental conditions such as exposure of the keyboard membrane to humidity and/or liquids.

[0008] Figure 1 illustrates a profile view of the example of a keyboard membrane including sealed conductive traces according to the disclosure. The keyboard membrane 100 includes a first circuit 104, a second circuit 106, a layer of UV curable material including a first layer of UV curable material 108 and a second layer of UV curable material 1 10, a first adhesive layer 1 12, a second adhesive layer 1 14, and a spacer 1 16. However, while Figure 1 illustrates the keyboard membrane as including a particular number of elements, the present disclosure is not so limited. Rather, elements shown in the various figures herein can be added, exchanged, and/or eliminated so as to promote various aspects of sealed conductive traces according to the disclosure. For example, while Figure 1 illustrates the keyboard membrane 100 as including the spacer 1 16, in some examples, the spacer 1 16 can be removed from and/or not included in the keyboard membrane such that the keyboard membrane 100 does not include a spacer.

[0009] The first circuit 104 can include a first conductive trace (not shown for ease of illustration in Figure 1 ) and a first key contact 105. The first conductive trace is coupled to the key contact 105. The second circuit 106 can include a second conductive trace (not shown for ease of illustration) and a second key contact 107. The second conductive trace is coupled to the second key contact 107.

[0010] The conductive traces, in some examples, are silver conductive traces. That is, the first conductive trace can be silver conductive trace and/or the second conductive trace can be a silver conductive trace. However, the present disclosure is not so limited. Rather, the conductive traces can be formed of a variety of suitable materials including silver and carbon and/or combinations thereof, among other types of suitable materials.

[0011] The second key contact 107 is to contact the first key contact 105, for example, when the first key contact 105 of the first circuit 104 is displaced by a displacement force applied to a key 1 18 coupled to the first key contact 105, among other possibilities to contact the first key contact 105 and the second key contact 107. For instance, the first key contact 105 may be displaced along a path of travel that is substantially perpendicular to the first circuit 104 and/or the second circuit 106. Contact between the first key contact 105 and the second key contract 107 can include causing the first key contact 105 to move along the path of travel to be positioned adjacent to and/or substantially adjacent to the second key contact 107 to couple (e.g., electrically couple) the first key contact 105 with the second key contract 107.

[0012] As illustrated in Figure 1 , the keyboard membrane 100 can include a layer of UV curable material including the first layer of UV curable material 108 and the second layer of UV curable material 1 10. In various examples, the layer of UV curable material overlays a portion of each of a first conductive trace and a second conductive trace to seal the first conductive trace and the second conductive trace, as described herein in greater detail with respect to Figure 2. Put another way, the layer of UV curable material can include a respective layer of UV curable material overlaying a portion of the first conductive trace and a respective layer of UV curable material overlaying a portion of the second conductive trace.

[0013] The UV curable material can be a UV curable ink or other type of UV curable material suitable to promote keyboard membranes including sealed conductive traces including those having desired humidity resistance and/or waterproofing qualities particularly with respect to humidity and/or liquids surrounding and/or in contact with the keyboard membranes. Examples of UV curable inks include Jelcon IN® and/or Jelcon INS® series UV curable inks available from JUJU chemical co. ltd™., among other suitable UV curable inks.

[0014] The UV curable material overlaying a portion of each of the first conductive trace and the second conductive trace to seal the first conductive trace and the second conductive trace can be from 10 microns to 100 microns thick. That is, the first layer of UV curable material 108 and/or the second layer of UV curable material 1 10 can have a respective thickness from 10 microns to 100 microns. All individual values and subranges from 10 microns to 100 microns of thickness are included; for example, the thickness of the first layer of UV curable material 108 and/or the thickness of the second layer of UV curable material 1 10 can have from a lower limit of 10 microns, 15 microns, 25, or 40 microns to an upper limit of 100 microns, 90 microns, or 60 microns of thickness of the UV curable material overlaying a portion of the first conductive trace and/or the second conductive trace to seal the first conductive trace and/or the second conductive trace. For example, the first layer of UV curable material can have a particular thickness extending substantially perpendicular from a planar surface of the first circuit 104 including the first conductive trace toward the second conductive circuit such that the thickness is equal to a total number of microns of the UV curable material extending from the planar surface of the first circuit 104 and/or a planar surface of the first conductive trace included in the same. In various examples, the planar surface of the first circuit 104 and the planer surface of the first conductive trace can be co-planar.

[0015] The keyboard membrane 100 can include a first adhesive layer 1 12 disposed on the layer of UV curable material overlaying at least a portion of the first conductive trace (i.e., the first layer of UV curable material 108). Similarly, the keyboard membrane 100 can include a second adhesive layer 1 14 disposed on the layer of UV curable material overlaying at least a portion of the second conductive trace (i.e., the second layer of UV curable material 1 10). The adhesive can be a solvent based adhesive, a pressure sensitive adhesive, a contact adhesive, a multi-part adhesive, and/or a one-part adhesive, among other types of adhesives suitable to promote sealed conductive traces.

[0016] In some examples, the keyboard membrane 100 can include a first adhesive layer 1 12, a second adhesive layer 1 14, and a spacer 1 16 that are each positioned between the first circuit 104 and the second circuit 106, as illustrated in Figure 1. For example, as, as illustrated in Figure 1 , the spacer 1 16 can be positioned between the first adhesive layer 1 12 and the second adhesive layer 1 14 such that each are positioned between the first circuit 104 and the second circuit 106. However as mentioned, in some examples the keyboard membrane 100 can be formed without a spacer.

[0017] The spacer 1 16 can be formed of plastic such as polyethylene

terephthalate, among other materials and/or combinations of materials. The spacer 1 16 can promote various performance characteristics, for example, disposition of the first circuit 104 and the second circuit 106 to have a desired force to fire (i.e., an amount of force applied to the keyboard membrane 100 sufficient to complete a switch formed between the first key contract 105 and the second key contract 107. The spacer 1 16 can form a portion of a distance separating the first circuit 104 from the second circuit [0018] The keyboard membrane 100 includes an opening 1 19 to permit the first key contact 105 to contact the second key contact 107. For example, the opening 1 19 can extend from the first key contact 105 of the first circuit 104 to the second key contract 107 of the second circuit 106 through each of the layer of UV curable material (i.e., the first layer of UV curable material 108 and the second layer of UV curable material 1 10), the adhesive layer (i.e., the first adhesive layer 1 12 and the second adhesive layer 1 14), and the spacer 1 16, as illustrated in Figure 1. The opening 1 19 can have a width that varies along a length 120 of the opening 1 19.

[0019] As shown in Figure 1 , a width W2 of the opening 1 19 is comparatively greater at the second layer of UV curable material 1 10 than a width Wi of the opening 1 19 at the second adhesive layer 1 14. Similarly, the width of the opening 1 19 is comparatively greater at the first layer of UV curable material 108 than a width of the opening 1 19 at the first adhesive layer. Such an opening alone or in combination with cutouts, as described herein, can promote desired performance characteristics of a keyboard membrane including promoting a desired force to collapse the dome 1 18 (e.g., the desired force can be equal and/or in excess of a predetermined amount of force to collapse the dome 1 18) and/or a desired force to fire (e.g., the desired force to fire equal and/or in excess of a predetermined amount of force to fire), among other performance characteristics. Notably, at least of portion of the opening 1 19 extends from the first key contact 105 to the second key contact 106.

[0020] Figure 2 illustrates a top view of an example of a portion of a keyboard membrane 260 including sealed conductive traces according to the disclosure. It is noted that keycaps, key mechanisms, and domes of the keycaps have been omitted for Figure 2 for ease of illustration. The keyboard membrane 260 is analogous to keyboard membrane 100 reference by Figure 1. The keyboard membrane 260 can include a plurality of cutouts 262-1 , 262-2, 262-3, 262-C, a plurality of conductive traces such as a first conductive trace 266 included in a first circuit 204, a first key contract 205 included in the first circuit 204, and a plurality of electrical bridges 268-1 , 268-2, 268-3, 268-4, 268-5, 268-6, 268-7, 268-8,..., 268-B.

[0021] Electrical bridges 268-1 268-B may refer to electrical traces that are separate and distinct from the conductive traces that are coupled to the key contacts (e.g., the first conductive trace 266 coupled to the first key contact 205). For example, electrical bridges 268-1 ,... 268-B can provide power to the first circuit and/or the second circuit and/or couple a portion of the keyboard membrane (e.g., a key) to another portion of the keyboard membrane 260.

[0022] Notably and in contrast to other approaches that may merely apply an electrical insulator to electrical bridges 268-1 , ..., 268-B, the keyboard membrane 260 includes a layer of UV curable material overlaying a portion of each of the first conductive trace 266 and/or the second conductive trace to seal the first conductive trace 266 and/or the second conductive trace. That is, depending upon a desired application of the keyboard membrane 260, the portion of each of the first conductive trace 266 and the second conductive trace overlaid with respective layers of the UV curable material can be varied.

[0023] For example, some or all of the each of the first conductive trace 266 and the second conductive trace can be overlaid with respective layers of the UV curable material to form UV curable material having a particular thickness, as described herein, to seal the first conductive trace 266 and/or the second conductive trace. That is, similar to the first conductive trace 266, the keyboard membrane 260 can include a second conductive trace (not shown for ease of illustration) included in a second circuit (not shown for ease of illustration). In some examples, the layer of UV curable material overlays an entire length of at least one of the first conductive trace 266 and the second conductive trace. For instance, both the firs first conductive trace 266 and the second conductive trace can have each of their entire lengths overlaid with the UV curable material.

[0024] The keyboard membrane 260 can include a plurality of cutouts 262-1 , 262-C extending through the first circuit 204. The plurality of cutouts 262-1 , 262-C (e.g., each of plurality of cutouts) can be coupled to the opening in the keyboard membrane 260 described with respect to Figure 1. For example, the plurality of cutouts 262-1 ,..., 262-C can permit a key (e.g., key 1 18 as described with respect to Figure 1 ) to travel through the plurality of cutouts. For instance, the plurality of cutouts 262-1 , ..., 262-C can permit a key to travel through the cutouts and/or into a portion of a volume of the space in the keyboard membrane, as described herein. [0025] While Figure 2 illustrates four cutouts having particular shapes and orientations the present disclosure is not so limited. That is, a total number, location, and/or shape, among other aspects of the plurality of cutouts 262-1 , ... , 262-C can be varied to promote sealed conductive traces. Similarly, a total number, locations, and/or materials of the conductive traces, among other aspects of the conductive traces can be varied to promote keyboard membranes including sealed conductive traces.

[0026] Figure 3 illustrates a flow diagram of an example of a method of manufacture of keyboard membranes including sealed conductive traces according to the disclosure. As illustrated at 384, the method 380 can include providing a first circuit including a first conductive trace and a first key contact, where the first conductive trace is coupled to the key contact. Similarly, the method 380 can include providing a second circuit including a second conductive trace and a second key contact, where the second conductive trace is coupled to the second key contact, as illustrated at 386. Providing can include manufacture of and/or otherwise procuring the first circuit and the second circuit.

[0027] As illustrated at 388, the method 380 can include disposing a layer of UV curable material on a portion of each of the first conductive trace and the second conductive trace to seal the first conductive trace and the second conductive trace. Disposing the layer of UV curable material on the portion (e.g., along an entire length of) of each of the first conductive trace and the second conductive trace can include printing a UV curable material (e.g., a UV curable ink) on the portion of each of the first conductive trace and the second conductive trace. For instance, the method can include screen printing the layer of UV curable material on the portion of each of the first conductive trace and the second conductive trace.

[0028] In some examples, the method 380 can include disposing a first adhesive layer and/or disposing the second adhesive layer, for instance, such layer(s) can be disposed by printing the adhesive on a first layer of UV curable material and/or on a second layer of UV curable material, among other possibilities mechanisms to dispose adhesive on the first layer of UV curable material and/or on the second layer of UV curable material. [0029] The method 380 can, in some examples, include forming an opening having varying widths. For example, by disposing successive layers on a portion of a surface area of a surface of a substrate (e.g., a first circuit) can provide a resultant opening, as described herein, having varying width. Regardless, as mentioned, at least a portion of the opening extends from a first circuit to a second circuit. For instance, at least a portion of the opening extends for a first key contact of a first circuit to a second key contact of a second circuit to provide a potential for contact of the first key contact with the second key contact in response to a displacement force applied to a keyboard membrane.

[0030] It will be understood that when an element is referred to as being "on," "connected to", "coupled to", or "coupled with" another element, it can be directly on, connected, or coupled with the other element or intervening elements may be present. In contrast, when an object is "directly coupled to" or "directly coupled with" another element it is understood that are no intervening elements (adhesives, screws, other elements) etc.

[0031] In the foregoing detailed description of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration how examples of the disclosure may be practiced. These examples are described in sufficient detail to enable those of ordinary skill in the art to practice the examples of this disclosure, and it is to be understood that other examples (e.g., having different thickness) may be utilized and that process, electrical, and/or structural changes may be made without departing from the scope of the disclosure.

[0001] The figures herein follow a numbering convention in which the first digit corresponds to the drawing figure number and the remaining digits identify an element or component in the drawing. For example, reference numeral 105 may refer to element 105 in Figure 1 and an analogous element may be identified by reference numeral 205 in Figure 2. Elements shown in the various figures herein can be added, exchanged, and/or eliminated so as to provide a number of additional examples of the disclosure. In addition, the proportion and the relative scale of the elements provided in the figures are intended to illustrate the examples of the disclosure, and should not be taken in a limiting sense. Further, as used herein, "a number of an element and/or feature can refer to one or more of such elements and/or features. Further still, while some elements are designated as a "top" view those of ordinary skill in the art will recognize that such orientations may correspond to a "bottom" view in some applications in order to practice the examples of this disclosure

Claims

What is claimed:

1. A keyboard membrane including sealed conductive traces, comprising:

a first circuit including a first conductive trace and a first key contact of the keyboard membrane, wherein the first conductive trace is coupled to the key contact; a second circuit including a second conductive trace and a second key contact of the keyboard membrane, wherein the second conductive trace is coupled to the second key contact, and wherein the second key contact is to couple to the first key contact; and

a layer of ultraviolet (UV) curable material overlaying a portion of each of the first conductive trace and the second conductive trace to seal the first conductive trace and the second conductive trace.

2. The keyboard membrane of claim 1 , wherein the layer of UV curable material overlays an entire length of at least one of the first conductive trace and the second conductive trace.

3. The keyboard membrane of claim 1 , wherein the first conductive trace and the second conductive trace are silver conductive traces.

4. The keyboard membrane of claim 1 , wherein the layer of UV curable material includes a first layer of UV curable material overlaying a portion of the first conductive trace and a second layer of UV curable material overlaying a portion of the second conductive trace.

5. The keyboard membrane of claim 1 , comprising a first adhesive layer, a second adhesive layer, and a spacer that are each positioned between the first circuit and the second circuit, and wherein the spacer is positioned between the first adhesive layer and the second adhesive layer.

6. The keyboard membrane of claim 1 , wherein the layer of UV curable material is from 10 microns to 100 microns thick.

7. The keyboard membrane of claim 1 , comprising an opening to permit the first key contact to contact the second key contact.

8. A keyboard membrane including sealed conductive traces, comprising:

a first circuit including a first conductive trace and a first key contact, wherein the first conductive trace is coupled to the key contact;

a second circuit including a second conductive trace and a second key contact, wherein the second conductive trace is coupled to the second key contact, and wherein the second key contact is to contact the first key contact;

a layer of ultraviolet (UV) curable material overlaying a portion of each of the first conductive trace and the second conductive trace to seal the first conductive trace and the second conductive trace;

a first adhesive layer disposed on the layer of UV curable material overlaying the portion of the first conductive trace;

a second adhesive layer disposed on the layer of UV curable material overlaying the portion of the second conductive trace; and

a spacer positioned between the first adhesive layer and the second adhesive layer.

9. The keyboard membrane of claim 8, comprising at least a portion of an opening extending from the first key contact to the second key contact and through each of the first layer of UV curable material, the first adhesive layer, the spacer, the second adhesive layer, and second layer of UV curable material.

10. The keyboard membrane of claim 9, wherein the opening is coupled to a plurality of cutouts extending through the first circuit.

1 1. The keyboard membrane of claim 9, wherein a width of the opening is comparatively greater at the second layer of UV curable material than a width of the opening at the second adhesive layer.

12. The keyboard membrane of claim 8, wherein the UV curable material is a UV curable ink.

13. The method of manufacture of a keyboard membrane including sealed conductive traces, comprising:

providing a first circuit including a first conductive trace and a first key contact of the keyboard membrane, wherein the first conductive trace is coupled to the key contact;

providing a second circuit including a second conductive trace and a second key contact of the keyboard membrane, wherein the second conductive trace is coupled to the second key contact; and

disposing a layer of ultraviolet (UV) curable material on a portion of each of the first conductive trace and the second conductive trace to seal the first conductive trace and the second conductive trace.

14. The method of claim 13, wherein disposing the layer of UV curable material includes screen printing the layer of UV curable material on the portion of each of the first conductive trace and the second conductive trace.

15. The method of claim 13, comprising forming an opening having varying widths, wherein at least a portion of the opening extends from the first circuit to the second circuit.