WO2016167986A2

WO2016167986A2 - Articles incorporating discrete elastomeric features

Info

Publication number: WO2016167986A2
Application number: PCT/US2016/025484
Authority: WO
Inventors: Stephen A. Johnson; Michael Benton Free; Margot A. BRANIGAN; Robert M. Jennings; Ronald W. Ausen; William J. Kopecky
Original assignee: 3M Innovative Properties Company
Priority date: 2015-04-17
Filing date: 2016-04-01
Publication date: 2016-10-20
Also published as: WO2016167986A3; TW201702060A; CN107531026A; JP2018513038A; KR20170137851A

Abstract

A lamination transfer film includes multiple discrete rows of an elastomeric material with spaces separating adjacent rows. A peelable liner disposed over the rows and in the spaces between the adjacent rows, wherein the peelable liner is not substantially adhered to the elastomeric material.

Description

ARTICLES INCORPORATING DISCRETE ELASTOMERIC FEATURES

TECHNICAL FIELD

This disclosure relates generally to lamination transfer films tor eiastomeric features and to associated systems and methods.

BACKGROUND

The ability to sense and measure the force and/or location of a touch applied to a surface is useful in a variety of contexts. As a result, various systems have been developed in which force sensors are used to measure properties of a force (referred to herein as a "touch force^"" or an ''applied force") applied to a surface (referred to as a "touch surface"). Force sensors typically generate signals in response to the applied force that may be used, for example, to locate the position of an applied force on the touch surface as well as the amount force applied.

Determining the location of an applied force to a touch surface is of particular interest when the touch surface is that of a computer display or a transparent overlay in front of a computer display. Furthermore, the need for small, lightweight, and inexpensive devices that are capable of determining touch location is increasing due to the proliferation of mobile and hand-held devices, such as personal digital assistants (PDAs).

BRIEF SUMMARY

Some embodiments are directed to lamination transfer film that includes multiple discrete rows of an eiastomeric material with spaces separating adjacent rows. A peelable liner is disposed over the rows and in the spaces between the adjacent rows, wherein the peelable liner is not substantially adhered to the eiastomeric material.

According to some embodiments, a method includes coextruding an eiastomeric material and a liner material to form a lamination transfer film. The lamination transfer film has multiple discrete rows of eiastomeric material with spaces separating adjacent rows and a peelable liner of the liner material disposed over the rows of eiastomeric material and in the spaces between adjacent rows. The peelable liner is not substantially adhered to the eiastomeric material.

Some embodiments involve a method comprising forming a structured liner that includes channels. An eiastomeric material is disposed into channels of a structured liner. At least one of pressure and heat is applied to the eiastomeric material to form a lamination transfer film comprising multiple discrete rows of an eiastomeric material with spaces separating adjacent rows and a peelable liner disposed over the rows and in the spaees between the adjacent rows, wherein the peelable liner is not substantially adhered to the eiastomeric material

Some embodiments are directed to a device thai includes a first component and a second component with first and second primer layers disposed respectively on the first and second components. The device includes multiple discrete rows of an eiastomeric material with spaces separating adjacent rows, first surfaces of the rows of eiastomeric material adhered to the first primer layer and opposing second surfaces of the rows of eiastomeric material adhered to the second primer layer.

These and other aspects of the present application will be apparent from the detailed description below. In no event, however, should the above summaries be construed as limitations on the claimed subject matter, which subject matter is defined solely by the attached claims, as may be amended during prosecution.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 A is a cross sectional view of a lamination transfer film 100 in accordance with some embodiments:

FIG. 1 B is a perspective view of the multiple discrete rows of eiastomeric material 110 after the peelable liner shown in FIG. 1 A has been removed;

FIGS.2A through 2C illustrate a few of the possible cross sectional shapes for the eiastomeric material in accordance with various embodiments;

FIG. 2D illustrates a cross sectional view of eiastomeric rows wherein the spacing between the rows changes from row to row in accordance with some embodiments.

FIG, 2E illustrates a cross sectional view of eiastomeric rows that have various heights in accordance with some embodiments;

FIG. i illustrates a method of making a device that includes eiastomeric rows in accordance with some embodiments;

FIG.4A is a cross sectional view of a lamination transfer film arranged on a first primer layer in accordance with some embodiments;

FIG.4B is a cross sectional view of the subassembly alter the peelable Uner shown in FIG.4A is removed;

FIG.4C is a cross sectional view showing the subassembly of FIG.4B laminated to a second primer layer and second component in accordance with some embodiments; FIGS. 5 A and 5B provide cross sectional views of a device that includes multiple stacked layers of the eiastomeric rows in accordance with some embodiments;

FIG, 6 is a top view of an example pattern of the eiastomeric rows in accordance with some embodiments;

FIG. 7A shows a top view of a design for the eiastomeric rows that provides greater compressive and capacitive stiffness at edges of the device in accordance with some embodiments:

FIG. 7B shows a top view of a design chat provides greater compressive and capacitive stiffness near the center of the device in accordance with some embodiments:

FiGS. 8A and 8B illustrate a cross sectional view and a top down view of the configuration of a basic device described herein having of rows of eiastomeric material interspersed with air filled spaces;

FIG. 9A provides plots of total capacitance with respect to compression ratio for a 10 mm x 10 mm area of a 0.2 mm thick device comprised of eiastomeric rows with a dielectric constant of 2.7 for different values of air content in accordance with

embodiments discussed herein;

FIG, 9B provides plots of capacitance change with respect to compression ratio for a 10 mm x 10 mm area of a 0.2 mm thick device comprised of eiastomeric rows with a dielectric constant of 2.7 for different values of air content in accordance with

embodiments discussed herein;

FIG. 10A provides plots of the total restoring force as a function of compression ratio and applied force for a 10mm by 10mm square patch of 1 : 1 aspect ratio rows made with an elastomer with a shear modulus of 0.I MPa and for a range of air content values in accordance with embodiments discussed herein;

FIG. 10B provides plots of the mechanical compliance as a function of applied force for a 10mm by 10mm square patch of 1:1 aspect ratio rows made with an elastomer with a shear modulus of 0.1 MPa and for a range of air content values in accordance with embodiments discussed herein;

FIG. 11 provides plots of capacitive compliance versus applied load for a 10mm by 10mm area of a 0.2 mm structure of eiastomeric rows with a shear modulus of 0.1 MPa and a dielectric constant of 2.7 in accordance with some embodiments;

FIG. 12 provides comparative plots of capacitive compliance of the example used to generate the plots in FIG. 11 with an eiastomeric land to one side of the structure: FIG. 13 demonstrates the impact of polyimidc carrier layers and bonding films on capaeitive compliance of the structure;

FIG. 14 provides plots of the pressure to hydrolock divided by shear modulus of the elastomeric material with respect to air content of the structured layer for various row aspect ratios of the structured layer;

FIG. 15 shows plots of the capaeitive compliance of the structured layer with respect to applied load for a variety of air content values;

FIG. 16 provides plots of the capaeitive compliance of the structured layer with respect to aspect ratio of the elastomeric rows;

FIG. 1 ? provides a family of plots of capaeitive compliance versus applied load for various heights of the structured layer;

FIG. 18 includes a family of plots of capaeitive compliance of tlte structured layer with respect to applied load for various values of shear modulus;

FIG, 19 includes a family of plots of capaeitive compliance of the structured layer with respect to applied load for various values of dielectric constant of the elastomeric material;

FIG.20 includes a family of plots of capacilive compliance of the structured layer with respect to applied load for various values of the product of shear modulus and initial undeformed thickness;

FIG, 21 provides a family of plots of capaeitive compliance versus applied load for various ratios of land ihickness to initial undeformed thickness (H_AB) for a comparative structured layer having a land;

FIG. 22 provides the minimum air content required to enable a structured layer to support a maximum normalized pressure of P* with a given void efficiency;

FIG.23 includes plots of the maximum achievable C* for a structure versus air content for a range of void efficiencies and an elastomer dielectric constant of 2.7;

FIG.24 includes plots of a maximum achievable C* for a structure versus content for a range of elastomer dielectric constants and a void efficiency of 80%;

FIGS. 25 A - 25E show Monte Carlo results of random cases that were run over the variables in Table I ;

FIGS. 26A - 26C show Monte Carlo results plotted against variable clusters; and FIG. 27 illustrates a repeating pattern of series of slots into which the four separate material stream inputs were extruded in accordance with embodiments disclosed herein. The figures are not necessarily to scale. Like numbers used in the figures refer to like components.

DETAILED DESCRIPTION OF ILLUSTRATI VE EMBODIMENTS

Some embodiments described herein relate to a lamination transfer film configured to transfer multiple discrete rows of elastomeric material to surfaces. Some embodiments involve methods of producing the lamination transfer film and to devices thai incorporate the transferred discrete rows of elastomeric material. The approaches disclosed herein enable the precise placement of the discrete rows of elastomeric material at a specified height, width, and spacing between rows on the surface. The disclosed approaches result in the formation of highly elastic, highly compressible structures comprising multiple discrete rows of elastomeric material. The elastic properties of these structures compare favorably to the elastic properties of structures that include elastic features connected by connecting material.

For example, conventional solutions uti Iked for touch sensing applications have involved materials that have connecting material e.g., carrier layers, adhesives or a land, between the features. The lands tend to dampen the elastic response to deformation, limiting or preventing compression in the landing thickness as well as some of the surrounding area. This results in diminished performance and/or thicker structures. The need for thinner structures with greater sensitivity continues to increase. This application describes articles, methods, and devices that involve discreet (landless) rows of elastomeric material in a peelable liner, wherein the elastomeric rows are discrete and are not connected by connecting material. These elastomeric rows can be transferred to a variety of surfaces and are useful in many applications such as touch sensing and force sensing.

FIG. 1 A is a cross sectional view of a lamination transfer film 100 in accordance with some embodiments. The film 100 includes multiple discrete, rows of elastomeric material 110. A peelable liner 120 is disposed over the rows of elastomeric material 110 and in the spaces 115 between adjacent rows. The rows of elastomeric material 110 have width, W, height, H. and spacing. S. The elastomeric rows 110 have & free surface 111 that may be substantially flat, but may alternatively protrude or recede with respect to the adjacent surface of the peelable liner 121. The peelable liner 120 does not substantially adhere to the elastomeric material 110. FIG. 1B is a perspective view of the multiple discrete rows of elastomeric material 110 after the peelable liner has been removed. FIGS. 1 A and 1 B illustrate elastomeric material having a rectangular cross sectional shape, it will be appreciated that the elastomeric material may be formed to have other cross sectional shapes. In cross section, the sides of the elastomeric material may be substantially flat (substantially linear sides) or rounded (non-linear sides). FIGS. 2A through 2C illustrate a few of the possible cross sectional shapes for the elastomeric material, including triangular (FIG, 2A), truncated triangular (FIG.2B). semicircular (FIG, 2C). It will be appreciated that many other cross sectional shapes are possible, e.g., an hour glass shape. Cross sectional shapes that are slightly undercut are can be used, but substantially undercut shapes may make removing the peelable liner more difficult.

In some embodiments, the spacing between rows may vary with distance as shown in FIG. 2D. As an example. FIG. 2D shows first 241 and second 242 rows separated by a space of width Sj, second 242 and third 243 rows separated by a space of width S₂, and third 243 and fourth 244 rows separated by a space of width S₃. In some embodiments, the cross sectional shape of the rows can change from row to row as in FIG. 2E which shows first 251, and third 253 rows that have a triangular cross section with height C₁ and second 252 and fourth 254 rows that have a truncated triangular cross section with height C₂. Alternatively, one group of adjacent rows may have a first cross sectional shape and another group of adjacent rows may have another cross sectional shape.

In various embodiments, the height. HL of the elastomeric rows, width. W. of the elastomeric rows at the free surface 1 11, and spacing, S. between the elastomeric rows can be between about 50 μm to about 400 μm.

The aspect ratio of the rows is equal to W/H. In various embodiments the aspect ratio may be greater than about 0.3 and less than about 10. For example, the aspect ratio of the rows is about 2 in some embodiments. In some embodiments, the aspect ratio of the rows is about 1.

The duty cycle of the rows is equal to the percentage (by volume) of the elastomeric material in one period comprising an elastomeric row plus an adjacent space occupied by the peelable liner.

Duty cycle % = W/(W+S) x 100.

In various embodiments the duty cycle may be between 5% and 99%_f between

10% and 90% or between 25% to 75%. For example, the duty cycle of the rows is 50% in some embodiments.

Before the peelable liner is removed, the peelable liner material fills the spaces between the elastomeric rows. A lamination transfer film, e.g., as shown in FIG, 1 A, may be characterized by eiasiomer content. In various embodiments the elastomer content of the lamination transfer film (before the peelable liner is removed) may be between 5% and 99%, between 10% and 90% or between 25% to 75%.

In the case of rectangular cross sections of the elastomeric material:

Duty Cycle = Elastomer content = 100% - peelable liner content (amount of peelable liner between rows).

In all the other cases the relationship is more complicated due to the geometry. In most other cases:

Duty Cycle is about equal to Elastomer content - 100% - peelable liner content. After the peelable liner is removed, air fills the spaces between the elastomeric rows. An arrangement of elastomeric rows, e.g., as shown in FIGS. IB.2A ··· 2E. may be characterized by elastomer content and/or by air content.

In the case of rectangular cross sections;

Duty Cycle = Elastomer content = 100% - Air content

Duty Cycle is about equal to Elastomer content = 100% - Air content The elastomer content (after the peelable liner is removed) may be in a range between 10% to 90% or between 25% to 75% for example. In some embodiments, the duty cycle and/or elastomer content may vary with distance longitudinally along rows and/or from row to row or as discussed in more detail herein.

In some implementations, the shear modulus of the elastomeric material can be less than about 500 MPa, for example, or in a range of about 0.01 MPa to about 10 MPa, or in a range of about 0.1 MPa to about 1 MPa. for example. The change in shear modulus over a temperature range of -20 C to 60C is less than about 50%. The elastomeric material may have a glass transition temperature less than about -30 C and a tan delta less than or equal to about 0.5 measured at 20 C with 1 Hz shear sweep mode, plate-on-plate. It will be appreciated that shear modulus and height of the elastomeric rows are related parameters.

Structures that incorporate the elastomeric rows (after removal of the peelable liner) can be characterized by mechanical compliance which is the derivative of the force with respect to the compression tatio, where the compression ratio is the derbrmed height (thickness) of the layer di vided by the initial thickness of the layer. In some

embodiments, the shear modulus divided by the undetbrmed height (G/H in MPa/mm) of the structure can be less than 1000. less than 200, less than 100, less than 30. or even less than 7. These values provide a mechanical compliance of the structure in mtn/MPa between about 0.02 to about 0,5 for example.

Structures that incorporate electrodes separated by the elastomeric rows (after the peelabie liner is removed) can be characterized by capacitive compliance (change in capacitance with respect to applied force) which is a consideration for touch or force sensing applications. Capacitive compliance depends in part on the dielectric constant of the elastomeric material. The dielectric constant of the elastomeric material can range from I to 100. Many unfilled elastomer materials suitable for the structures described herein can have dielectric constants between 1.5 to and about 3. For example, a useful elastomer, silicone polyoximide. has a dielectric constant of about 2.7.

In various embodiments, the thickness (undetbrmed height, H) of the elastomeric rows can be between about 0.01 and 10 mm. In some embodiments, the product of shear modulus and underbrmed height divided by the dielectric constant of the elastomer (GH/k in MPa*mm) of the structure can be less than 13, less than I . less than 0,1 , or even less than 0.01. These values of GH/k provide capacitive compliance of the device that includes capacitive electrodes in femtoFarad per grain force (fF/gl) between about 0.5 to about 100 for example. In some embodiments, the capacitive compliance is greater than 2 fF/g.

Useful materials tor the elastomeric material include thermoplastic elastomers such as styrenic block copolymers, polyolefin blends, elastomeric alloys, thermoplastic polyurethanes, thermoplastic copolyesler, and thermoplastic polyamides. Useful thermoplastic elastomers include silicone thermoplastics, such as silicone polyoximide. e.g.. as described in commonly owned U.S. Patent 7,501.184 which is incorporated herein by reference. The elastomeric material may be an olefin block copolymer such as

INFUSE™ 9500 available from The Dow Chemical Company, Midland. Michigan, or styrenic block copolymers e.g.. SEBS block copolymers, such as ΚΕΑΤΟΝ® G1645 available from Kraton Polymers LLC. Houston, Texas and SIS block copolymers, such as KRATON®10 D1161 available from Kraton Polymers LLC. The elastomeric material may^¬ be an ethylene/octene copolymer such as EXACT™ 8201, available from ExxonMobile Chemical, Houston Texas.

Additional useful materials for the elastomeric material include thermosets. such as Polydimethylsiloxane (PDMS). or other silicon-based organic polymers.

The peelabie liner can be a flexible material and may have a flexural rigidity of 0.002 to 2 Pa*m\ For example, the peelabie liner may comprise a thermoplastic material and/or an olefin, such as polypropylene or polyethylene. The peelable liner is noi substantially attached to the elastomeric rows, For example_* non-substantial attachment of the peelable liner to the elastomeric rows is characterized by a peel force less than about 100 grams per inch, (180 degree peel). In some embodiments the peelable liner includes a release additive such as Momentive SF1642, Additionally, the release liner exhibits a degree of flexibility.

In accordance with some embodiments, a method of making the lamination transfer film shown in FIG. 1 A involves coextruding an elastomeric material and a liner materia! to form multiple discrete rows of elastomeric material with spaces separating adjacent rows and a peelable liner of the liner material, wherein the peelable liner is not substantially adhered to the elastomeric material.

During the coexirusion, flowrates of the elastomeric material and/or the liner material can be controlled to maintain selected predetermined values so that the free surfaces of the rows have a predetermined shape, e.g„ are substantially flat, protruding, or recessed,

Systems and methods that can be used for coextruding the lamination transfer films described in this disclosure are discussed in detail in commonly owned U.S. Patent Publication 2013/0009336 which is incorporated in its entirety herein.

In accordance with some embodiments, a method of making the lamination transfer film shown in FIG. 1 A involves forming a structured liner having channels and disposing an elastomeric material into the channels of a structured liner. For example, disposing the elastomeric material into the channels of a structured liner may be achieved by extruding the elastomeric material at an appropriate thickness (calculated based on void space of the structured liner) and then running the liner and extrudate into a heated nip. It has been shown that elevated temperatures (e.g. about 120 C) and sufficient pressure (e.g., greater than about 200 PSI) applied to the elastomer + structured liner will lead to filling the structured liner with high fidelity. In this particular instance, the liner would need to have a melt point well in excess of 120 C (e.g. HOPE, PC).

In accordance with some embodiments, a method of making the lamination transfer film shown in FIG. 1 A involves forming a structured liner having channels and disposing an elastomeric materia! via solution coating the elastomer onto the structured liner. The process includes skiving off the excess material from the non-structured areas. Solvent may be driven off by heating the filled liner and conveying through an oven. Repeated passes and high solids solutions can be used for making a practical and/or efficient process for generating structures in this fashion. Silicone polyoxami.de, dissolved in hexanes and coated into to a structured HDPB liner would be one example method to manufacture these articles.

The flow diagram of FIG. 3 and the cross sectional diagrams of FIGS. 4A through 4C illustrate a device that incorporates the ciastomeric rows and a method of making the device. A lamination transfer film 100 comprising rows of ciastomeric material 110 and a peelable liner 120 as shown in FIG. 1 A and described in the associated text is formed 310, e.g.. by coexlmsion as described above. A first primer layer 41.1 is coated 320 onto the surface of a first component 421 upon which the elastomeric rows 1 10 are to be affixed. For example, the first component 421 may be or comprise an electrode layer., a barrier film, or an adhesive layer. As shown in FIG.4A, one or more lamination transfer films 100 are arranged 330 on the first primer layer 411 so that the free surfaces 111 (see FIG. 1 A) of the elastomeric material 110 are adjacent to the first primer layer 41 1. More than one lamination transfer film 100 may be arranged on the first primer layer 411 in a pattern, e.g.. a tiled pattern. In some implementations, a lamination transfer pattern may be cut and placed on the primer layer 411 so that the longitudinal axes of the rows are at an angle to one another, e.g., 90 degrees, One example pattern is shown in FIG.6. The lamination transfer film 100. the primer layer 411., and the first component 421 are laminated 335 together using one or both of heat and pressure to form subassembly 410. The peelable liner 120 is removed 340. FIG.4B shows subassembly 420 after removal of the peelable liner.

A second primer layer 412 is coated 350 onto the surface of a second component 422 upon which the elastomeric rows 110 are to be affixed. For example, the second component 422 may be or comprise an electrode layer, a barrier film, or an adhesive layer. Subassembly 420 is arranged 360. e.g., by a pick-and-place process, on the second primer layer 412 so that surfaces 112 of the elastomeric material 110 that were previously- covered by the peelable liner are adjacent to the second primer layer 412. Subassembly 420, the second primer layer 412. and the second outer layer 421 are laminated 370 together using one or both of heat and pressure to form device 430 as shown in FIG.4C.

In some configurations, a device may include multiple layers of the elastomeric rows stacked vertically, as depicted in FIGS. 5A and 5B. FIGS. 5A and 5B show devices 501 , 502 that include first and second layers 51 L 512 of elastomeric rows wherein the longitudinal axes of the elastomeric rows of the first layer 511 are arranged at an angle with respect to the longitudinal axes of the elastomeric rows of the second layer 512. In the examples of FIGS. 5 A and SB the longitudinal axes of the elastomeric rows of the first layer 511 arranged generally along the x direction and the longitudinal axes of the elastomcric rows of the second layer 512 are arranged generally along the y direction.

Device 501 shown in FIG. 5 A includes a first primer layer 521 disposed on a first outer layer 531 and a first layer 511 of elastomeric rows affixed to the first primer layer 521. A second primer layer 522 is disposed on a second outer layer 532 and a second layer 512 of elastomcric rows is affixed to the second primer layer.

Device 502 shown in HG. SB, includes an optional inner layer 533 with optional third 523 and fourth 524 primer layers.

The first and second primer layers of the present disclosure may include hut are not limited to, at least one of silicone thermoplastic elastomer, e.g.. silicone polyoxamide. oiet!n and styrene based block copolymer, e.g. styi¾ne«ethylene«butadiene-styrene and styrene-isoprene-styrene, polyacrylates, e.g. polyester acrylate and polyurethane acrylate, fumed silica, functionated fumed silica, silanes, litinates, zirconates and siloxanes.

Combinations of these materials may be used.

in some embodiments, the primer layers include a silicone thermoplastic elastomer, e.g. polydiorganosiloxane polyoxamide, linear, block copolymers, i.e. silicone polyoxamide. such as those disclosed in U.S. Pat. Nos. 7,371.464 (Sherman, et. al.) and 7,501,184 (Leir, et. al.), which are incorporated herein by reference in their respective entireties. The primer layers that include a silicone thermoplastic elastomer may also include a coupling agent. Useful coupling agents include, but are not limited to silane coupling agents (e.g., organotrialkoxysi lanes), titanates, 'zirconates, and organic acid- chromium chlorides coordination complexes. Organosilanes are particularly useful coupling agents. In some embodiments, the coupling agent comprises an organosilane coupling agent represented by the formula:

wherein R^l is an monovalent organic group and each Y is independently a hydrolyzable group. In some embodiments, R* has from 2 to 18 carbon atoms. In some embodiments,

R * has from 3 to 12 carbon atoms and is selected from the group consisting of epoxyalkyl groups, hydroxyalkyl groups, carboxyalkyl groups, amineaikyl groups, acryloxyalkyl groups. and methacryloxyalkyl groups. In some embodiments, each Y is independently selected from the group consisting of

represents an alkyl group having from I io 4 carbon atoms.

Suitable silane coupling agents include, for example, those identified in U.S. Pat. No, 3.079.361 (Piueddemann). Specific examples include: (3- acryloxypropylHrimethoxysilane, N-(2-aminoethyl>-3-aminopropy!trimethoxysilane- 3^ aminopropy hriethoxysi lane, 3 -am ί nopropy Itrimethoxysi lane, (3 - glycidoxypropyl )trime.hoxysi lane. 3-mcrcaptopropyUrimethoxysi lane, 3- methacryloxypfopyltrimethoxysilane, vmyltrimetboxysiiane (all available from Gelest, Inc., Morrisville. Pennsylvania), and those available under the trade designation

"XIAMETER" from Dow Coming Corp.. Midland, Michigan such as

vinylbenzyiaminoethylaminopropyUrimethoxysiiane (supplied as 40% in methanol , XIA METER OFS-6032 SI LANE), chloropropyltrimethoxysilane (XIAMETER OFS-6076 SILANE), and atmnoethylaminopvopyluimelhoxysilane (XIAMETER OFS-6094

SILANE),

Suitable litanate coupling agents include, for example, those identified in U.S.

Patent No.4,473,671 (Green). Specific examples include isopropyl triisostearoyl titanate. isopropyl tri(lauryl-myristyl) titanate, isopropyl isosiearoyl dimethacryl titanate: isopropyl tri(dodecyi-benzenesulfonyl) titanate, isopropyl isostearoyl diacryl titanate, isopropyl (ri(diisooctyi phosphato) tri(diociylpyrophosphato) titanate, isopropyl triacryloyl titanate, and diisopropxy<ethoxyacetoacetyl) titanate. tetra(2,2-diallyoxymethyi)butyl

di(dttrideeyl)phospliito titanate (available as KR 55 from Kenrich Petrochemicals, Inc. (hereinafter Kenrich) Bayonne, New Jersey), neopentylfdiallyl)oxy trineodecanonyl titanate (available as L1CA 01 from Kenrich), neopenlylidiallyl)oxy tri(dodeeyl)benzene- sultbnyl titanate (available as L1CA 09 from Kenrich). neopentyl(diallyl)oxy

trifdioctyl )phosphato titanate (available as l.ICA 12 from Kenrich), neopentyl(dially)oxy tritdioctyl)pyro-phosphato titanate (available as LICA38 from Kenrich).

neopentyl(diallyl)oxy tri(N-ethylenediarmno)ethyl titanate (available as LICA 44 from Kenrich), neopentyl(diallyl)oxy lri(m-amino)phenyl titanate (available as LICA 97 from Kenrich), and neopentyl(diallyi)oxy trihydroxy caproyl titanate (formerly available as LICA 99 from Kenrich.

Suitable zirconate coupling agents include, for example, those identified in U.S. Pat. No.4,539,048 (Cohen). Specific examples include zirconium propionate, tetra(2.2« diallyloxymethyhbutyl di(ditridecyl)phosphito zirconate (available as KZ 55 from Kenrich), neopentyl(diallyl)oxy trineodecanoyl zirconate (available as NZ 01 from Kenrich), neopentyi(diallyl)oxy tri(dodecyl)benzenesulfonyl zirconate (available asNZ 09 from Kenrich), neopeniyl(diallyl)oxy tri(dioctyl)phosphato zirconate (available as NZ 12 from Kenrich), neopentyl(diallyl)oxy triidioctyl)pyrophosphato zirconate (available as NZ 38 from Kenrich), neopemyl(diallyl)oxy tri(N-ethylenediamino)ethyl zirconate (available as NZ 44 from Kenrich), neopemylidiallyhoxy tri(m-amino)phenyl zirconate (available as NZ 97 from Kenrich). neopentyhdiallyljoxy trimethacryl zirconate

(available as NZ 33 from Kenrich). neopentyl(diallyl)oxy triacryl 2irconate (formerly available as NZ 39 from Kenrich), dineopentyl(diailyl)oxy di(para-aminobenzoyl) zirconate (available as NZ 37 from Kenrich). and dineopentyl(diallyl)oxy di(3- mercapto)propionic zirconate (available as NZ 66 A from Kenrich).

Mixtures of one or more coupling agents may be used, although typically a single coupling agent is sufficient. The amount of coupling agent used may be from about 0.1 vvt. % to about 30 wt. %. from about 0.1 wl. % to about 25 wt. %, from about 0.1 wt. % to about 20 wt. %, from about Q.1 wt. % to about 15 wt. %, from about 0.1 vvt. % io about 10 wt. % or even from about 0.1 wt. % to about 5 wt. % based on the weight of the silicone thermoplastic elastomer.

In some embodiments, the primer layers that include a silicone thermoplastic elastomer may also include tackifier resin. Preferred tackifier resins include silicone tackifier resins referred to as MQ resins, including but not limited to. silicone resin available under the trade designation SILICONE MQ RESINS, .from Sillech Corporation, Toronto. Canada and silicon resin available under the trade designation MQ-RES1N POWDER 803 TF, from Wacher Chemie, Munich, Germany. The amount of tackifier resin used may be from about 5 wt. % to about 75 wt % or even 5% to about 50%. based on the weight of the silicone thermoplastic elastomer. In some embodiments, one or both of the first and second primer layer does not include a tackifier.

Commercially available primer layers may also be used, including, but not limited to, 3M ADHESION PROMOTER 111, available form 3M Company, St. Paul, Minnesota.

In some embodiments, the thickness of the first and second primer layers may be between about 50 nanometers and about 5 microns, between, about 200 nanometers and about 5 microns, between about 400 nanometers and about 5 microns, between about 50 nanometers and about 3 microns, between about 200 nanometers and about 3 microns, between about 400 nanometers and about 3 microns, between about 100 nanometers and about 1 micron, between about 200 nanometers and about 1 micron or even between about 400 nanometers and about I micron.

In some configurations, the first and second components 421, 422 of the device 430 shown in FIG.4C may be electrically conductive electrode layers, forming a device useful for capacitive touch or force sensing. In capacitive force sensing applications it is desirable to have lamination transfer films that enable a large change in capacitance lor a given compressive pressure applied on the film surface. Typically these applications require a low compression compliance, defined as the change of thickness of a fiat article in response to a pressure applied to the top surface. Given that elastomeric materials have generally high bulk moduli (produce small changes in volume in response to hydrostatic pressures), these devices require a significant fraction of air incorporated into the compressible layer.

One aspect of producing efficient force sensing devices is to create elastic and air regions that enable a specified amount of compression, e.g.. a maximum amount of compression, for a given load while reducing, e.g.. minimizing, the air content that degrades the capacitive response. Producing open ceiled structures such as the ones described herein is one approach to improving that efficiency since ihe air in the structure is allowed to escape rather than push back against loading.

Force sensing devices having a construction as generally shown in FIG.4C\ wherein the first and second structures are electrically conductive electrodes can have a capacitive compliance (change in capacitance with respect to force applied normal to the surface of an electrode) of less than 2 femtoFarads per gram of force (iF/^'gf). It may be desirable in force sensing applications for the capacitive response to be relatively constant with respect to applied pressure, short time response, temperature changes, atmospheric pressure changes, and long term usage.

In some cases a force sensor, or other device incorporating the elastomeric rows described herein, can be exposed to stray liquids such as water and it is desirable to reduce or prevent liquid penetration into the elastic layer that can compromise performance of the device. The elastomeric rows described herein arranged linearly can reduce or prevent liquid penetration in one direction. Other layouts, such as the one illustrated in FIG. 6. wherein the lamination transfer film (a top view is shown) is cut and arranged on the primer layer to form concentric square pattern 620 can obtain the effective elastic characteristic of an open cell structure while providing a barrier to external liquid penetration. The lamination transfer film described herein also provides the possibility of distributing the compressive and capaeitive stiffness to different regions in the device to open possible design options. FIGS. 7A and 7B show two examples wherein the spacing between the elastomeric rows varies with distance. FIG. 7A shows a top view of a design that provides greater compressive and capacitive .stiffness at edges of the device. FIG. 7B shows a top view of a design that provides greater compressive and capaeitive stiffness near the center of the device. Distributed design spacing as illustrated in FIGS. 7A and 7B may be used in combination with cutting and assembling (as shown in FIG.6) or simply stacking layers of elastomeric rows. e.g..0*790° oriented layers, (as shown in FIGS. 5A and 5B) to create a specified stiffness.

Examples:

Modeling Examples:

I ) Geometry and assumptions

As previously discussed, the basic device described herein consists of rows of elastomeric material interspersed with air filled spaces depicted as regions A and B in the cross sectional view of FIG. 8A and the top down view of FIG. 8B. We refer to this region as the 'structured layer' of the device. In some cases (Model 1 ) the structured layer was bonded directly to electrodes (material C) while in other cases (Model 2) the structured layer was bound to an insulating carrier layer (material C) which is in turn bonded to electrodes with a polymeric adhesive (material D). In yet another case (Mode! 3⁾. a "land region' is included wherein the land region is a continuous layer of elastomeric material just above or below the structured layer that may also be treated as the carrier layer for capacitance purposes. In all cases it is assumed that only the structured layer is deforming and that all other layers are far more rigid by comparison.

For the purposes of this analysis the following assumptions were made:

1. This is a plane-strain configuration and no deformation occurs along the axis parallel to the channels (x₂)

2. Deformation only occurs in materials A and B comprising the structured layer 3. Material B is incompressible (does not change volume with pressure, i.e. has a very large bulk modulus) and Material A is compressible air (does change volume with pressure, i.e. has a very low bulk modulus).

4. This is an 'open cell' structure so that Material A is allowed to flow out of and into the structure during compression and release and does not build any pressure upon

deformation. In some cases the ends of the channels may be sealed technically creating 'closed cell' structures. However in those cases we assume thai the length of the channels is sufficiently long relative to the region of compression that any restoring force resulting from the air pressure buildup during localized deformation is small relative to the restoring force coming from the deformed elastomer.

5. Material B is able to slide friction free at the interface with layer C. This is technically not true for these structures. Material B is bound to layer C and cannot move laterally at the interface. However it can be demonstrated that for elastomeric rows with aspect ratios (width/height) less than 1:1. the error in this assumption produces at most a 30% underrepresentation of the restoring force calculations in this analysis and very little impact on the capacitance calculations. if needed, a correction factor based on bead aspect ratio can simply be applied to the force calculations to account for the discrepancy. The correction factor is discussed below.

As the structured layer is compressed, the incompressible elastomeric material squeezes out sideways into the air regions while the air flows out of the structure. As a result, when looking at a top-down view of the structure (FIG. 8B) the areas of the elastomeric and air regions will change as follows:

where:

beads

the 'Compression ratio' is defined as the deformed thickness of the structured layer.

divided by the initial thickness of the structured layer:

η A useful metric for describing structures is the initial volume fraction of air in the structure.

where is the initial volume fraction air content in the structure and α is a geometry 5 factor for the structure defined as A/8:

It will also be useful to describe the air content in the compressed structure as we)!. To do (his we can think of our compression ratio in terms oi the initial and final volume of the structured layer as follows:

5

where:

are the volumes of the elastomer and air content in the compressed structure and

are the volumes of elastomer and air in the initial undeformed state. Note however that since the elastomer is incompressible the elastomer volumes in the compressed and initial state are identical:

25 Dividing both the numerator and denominator of equation (4) by the total volume of the structured layer and using the incompressibility condition in (5) we have:

where is defined in equation (2) and Φ is the volume fraction of air in the structured layer during compression. In the undeformed state Φ will be equal to During compression Φ will decrease until it reaches a value of Φ=0 which describes a

'hydroiocked' condition in the structure when all of the air has been pushed out of the layer. 2) Hydrolocking

In each of these structures there is a maximum allowable deformation the structured layer can withstand before the air regions are completely compressed and the system becomes 'hydroiocke". Any further compression would rely on the very small compressibility of the elastomer or upon elastomer squeezing out of the device itself Such deformation would require very large additional loads and not be useful in force sensing applications.

The hydrolocking limit on the compression ratio is simply equal to the elastomer volume content in the structure and is itself a relevant design criteria.

The hydrolocking limit in combination with the material stiffness and structure determined the maximum pressure the structured film can withstand and be useful for force sensing.

3) Capacitance

The capacitance of a parallel plate capacitor is calculated -from the capacitor geometric and dielectric properties as follows:

where:

When the capacitor consists of two regions, tor instance the air and an elastomer regions comprising the structured layer in figure (A I )_> the total capacitance is simply the sum of the capacitances of the individual regions as follows:

where CAB is the total capacitance of the structured layer within the total construction and h_AB is the deformed thickness of the structured layer. Combining equations (1). (2), (3), (8) and (9). CAB can be calculated as a function of compression ratio as follows:

where: S_app is the total area of the structured film

H_AD is the initial (undeformed) thickness of the structure film

Taking the derivative of ( 10) with respect to compression ratio (η) it can be seen that the change in capacitance with compression is not constant but changes with compression as follows:

Total capacitance (liquation ( 10)} and capacitance change with deformation (Equation ( 11 )) are plotted in FIGS. 9 A and 9B for a 10 mm .x 10 mm area of a 0.2 mm thick structure comprised of elastomeric rows with a dielectric constant of 2.7. The plots show that increasing the air content decreases the capacitance of the structured layer but also increases the deformation range of the layer allowing the capacitance to increase to even higher levels under deformation. The air content, has a similar effect on the derivative of capacitance with respect to deformation.

The total capacitance of the structure including layers C and D (see, FIG. is determined by adding the inverse of the capacitances of the individual layers as follows:

where Cc and C_D are the capacitances of the individual layers C and D. Equation (12) can be rewri iten as follows:

4) Load response

Assuming that the elastomer can he effectively represented by a common constitutive equations for hyperelastic materials such as the Mooney-Rtvlin equation for incompressible materials. It can be shown that the force versus deformation behavior of a patch of the structured layer with an area S_app can be described as follows:

where F_total is the total restoring force for a region and G is the shear modulus of the elastomer. The mechanical compliance is the derivative of the force with respect to the compression ratio calculated as follows:

The stress analysis above (equations 15 and 16) are based on the assumption of rrictionless sliding of the elastomer at the carrier interlace. The elastomer will be bound at that interface. To account for that discrepancy a correction factor to the load must be employed. We can find this, correction factor by comparing the results of a finite element mode) of a 2D, plane-strain cross section of an elastomeric bead with the fixed boundary condition to the results of the same model with a freely slipping boundary condition as used to generate equation (15).

To account for the adhesion of adhesive to layer(s) C the following correction factor may be applied to the load calculations:

where f is the correction factor and the quantity 22A/H_AB) is the full aspect ratio of the elastomeric bead, incorporating this correction factor into the load calculations, equations ( 15) and ( 16) are rewritten as:

The plots of FIGS. 10A and 10B show the total restoring force and the mechanical compliance as a function of compression ratio and applied force for a 10mm by 10mm square patch of 1 :1 aspect ratio rows made with on elastomer with a shear modulus of 0.1 MPa and with a range of air content in the overall structure. It can be seen from the plots of FIGS. 10A and 10B that adding air content increases the compliance of the structure at small deformations but that the compliance drops rapidly with loads. Structures with lower air content have a more constant mechanical compliance with load but also reach the hydrolocking limit at smaller loads as well.

5) Capacitive Compliance response

The capacitive compliance is the change in capacitance with application load. This can be found tor each structure by simply taking the ratios of equations (11) and ( 19) as follows:

From the equation above it can he seen that the capacitive compliance has an inverse relationship with structure thickness, H_AB. and the shear modulus of the elastomer. That means that the capacitive compliance will increase as the thickness of the structure is decreased. The capacitive compliance will also decrease as the stiffness of the elastomer is increased.

The capacitive compliance is plotted as a function of load for a channel structure with a range of air contents in FIG. 11. FIG. 11 is a plot of capacitive compliance versus applied load for a 10mm by 10mm area of a 0.2 mm structure of elastomeric rows with a shear modulus of 0.1 MPa and a dielectric constant of 2.7 (Model i). The plot of FIG. 1 1 shows thai increasing air content does increase capacitive compliance but only for smaller loads. When the load is sufficiently high the capacitive compliance is largely the same for all structures regardless of air content. The benefit of the air content at thai point is simply increasing the allowable load applied to the structure before hydrolocking occurs. In practical terms this means that there is a point of diminishing returns on capacitive compliance when adding air to the structure and the amount of air in the structure is substantially determined by the load range over which the structured layer needs to function. If the structure needs to accommodate larger loads then an elastomer with a higher shear modulus would be helpful.

6) Impact of land and carrier layers

If connecting material, e.g., earner layers, adhesives or a land ( Models 2 or 3). is present on the structured layer then the total capacitive compliance is determined by taking the derivative of equation (13) with respect to force yielding:

30

where is the capacitive compliance of the entire structure and the quantity

N was defined in equation (14).

If we consider the example used to generate the plot in FIG. 11 and add an elasiomeric land ιο one side of the structure (Model 3), equation (22) shows that the impact on the total capacitive compliance can be significant and negative. These effects are plotted in figure FIG. 12.

If we consider a structure (Model 2) composed of a 0.2mm structured layer sandwiched between two 12.5 μm thick layers of polyimide film (KC ^s 3.4) each with a 25 μm thick layer of thermal bonding film ίκο = 4.4) the impact over the simple structured layer (without connecting material as in Model 1 )) is shown in FIG. 13. FIG. 13 demonstrates the impact of polyimide carrier layers and bonding films on capacitive compliance of tlte structure.

7) Variable dependencies

Plots in FIGS. 14 - 21 show variation of parameters from the base case (Model 1) of the structured layer with the parameters listed below. If the variable is not listed on the plot its value is listed below:

Total Application Area: 100 mm² ( 10 mm x 10 mm)

Air Content: 50%

Bead Width/Height: L0

Thickness (height): 0.2 mm

Land thickness: 0 mm

Elastomer shear modulus: 0.1 MPa

Elastomer dielectric constant: 2.7

Carrier Layer: none

FIG. 14 provides plots of the pressure to hydrolock divided by shear modulus of the elastomeric material with respect to air content of the structured layer for various row- aspect ratios of the structured layer (Model 1 ).

The plots of FIG. 15 provide the capacitive compliance of the structured layer (Model 1 ) with respect to applied load for a variety of air content values. The family of plots of FIG. .16 provides the capacitive compliance of the structured layer (Model 1 ) with respect to aspect ratio of the elastomeric rows.

FIG. 17 provides a family of plots of capacitive compliance versus applied load tor various heights of the structured layer (Model 1 ).

FIG. I 8 includes a family of plots of capacitive compliance of the structured layer

(Model 1 ) with respect to applied load for various values of shear modulus.

FIG. 19 includes a family of plots of capacitive compliance of the structured layer (Model 1) with respect to applied load for various values of dielectric constant of the elastomeric material.

FIG. 20 includes a family of plots of capacitive compliance of the structured layer

( Model 1 ) with respect to applied load for various values of the product of shear modulus and initial undeformed thickness.

FIG. 21 provides a family of plots of capacitive compliance versus applied load for various ratios of land thickness to initial undeformed thickness (H_AB) for a structured layer having a land (Model 3).

6) Design of structured layers

A design objective is to find an operating range of structures that will produce a required capacitive compliance over a required load range while also minimizing the air content in the structure that often degrades other performance properties such as peel strength.

To help in this design we introduce the concept of 'void efficiency'. The ideal condition is when the hydrolccking condition occur, at the maximum required operating compressive pressure for the structure. If the hydroiocking condition occurs at pressures higher than the maximum operating range, that additional void space is not utilized effectively and the design is less than optimal. Based on this description we will define the void efficiency as follows:

(23) where

is the remaining air content in the structure when subjected to the maximum required compressive pressure and is the initial air content as defined earlier. If

then the void efficiency of the structure is 100%. If

then the void efficiency of the structure is 50% and so forth.

Next we can combine equation (23) with equations (6), (7) and (19) to give us the following:

where we introduce the quantity P* that we will herby call the 'Normalized maximum pressure'. We also recall that f is the load correction factor for boundary conditions defined as a function of row aspect ratio in equation (17):

To design an efficient structure we start by specifying the maximum pressure (maximum load on a specified area) that the structure must support and the targeted bead aspect ratio to calculate P* using equation (25). The required air content in the structure can then be determined using equation (26). Unfortunately, equation (26) cannot be easily solved directly for F_air as a function of P* . We can however create a plot of equation (26) that can be used for the same purpose, as shown below in FIG. 22. FIG.22 provides the minimum air content required to enable a structured layer to support a maximum normalized pressure of P* with a given void efficiency. FIG. 22 illustrates that for void efficiencies less than 100% there is a maximum value of P* a given structure could accommodate regardless of air content. To achieve higher load ranges an elastomer with a higher shear modulus can be used.

Once the optimal air content is determined, equation (21 ) can then be used to generate a design plot focused on structure design parameters required to achieve a particular eapacittve compliance. Equation (21 ) can be rewritten as follows:

where we introduce the quantity C* that we refer to as the 'normalized capacitive compliance'. Capacitive compliance is not constant with compression but decreases monotonically with increased compressive deformation. As a result it is most useful to evaluate (28) under the highest compression to ensure that the capacitive compliance always remains above the target. We can do that by substituting equation (24) into equation (28) as follows:

Equation (29) is plotted against air content for a range of void efficiencies and elastomer dielectric constants in FIGS. 23 and 24. FIG.23 includes plots of the maximum achievable C* for a structure versus air content for a range of void efficiencies and an elastomer dielectric constant of 2,7. FIG. 24 includes plots of a maximum achievable C* for a structure versus content for a range of elastomer dielectric constants and a void efficiency of 80%. For a specified air content, void efficiency, and elastomer dielectric constant, the plots show the achievable 'normalized capacitive compliance' for the structure. The allowable modulus and thickness of the structure can then be determined from equation (27)

Design Example #1 :

A structured film can be designed to provide a capacitive compliance of at least - 4fF/grOver a load range of 0 to Ikgr on a 10 mm xlO mm patch. The structured film uses an elastomer with a shear modulus of 0.1 MPa and a dielectric coefficient of 2.7. There is no land in the structure and no carrier layer. Assume a 80% void efficiency.

We will start out by considering three different bead aspect ratios (width/height): ½, I and 2. Using equation ( 17) we calculate our load correction factors as follows:

Usiiig equation (25) we calculate P* values as follows (Note that compressive forces are negative):

Using FIG.22 we calculate our optimal air content assuming 80% void efficiency:

From either FiG.23 or FIG, 24 we determine C* for our given air contents, dielectric constant and void efficiency:

Rearranging equation (27) and r

ecalling that we can calculate the maximum allowable thickness tor the construction:

This means the specifications can be met using all three aspect ratios. However the thicknesses of the constructions could be no greater than the values listed above for the given aspect ratio. The choice of final aspect ratio would likely be based on the balance of other properties, such as peel strength and processabiliiy dependent on structure thickness and air content.

In another example, the construction design was approached by asking what possible ranges of multiple variables can produce useful constructions, noting that there are multiple variables to consider. One approach to produce a working model is using a Monte-Carlo analysis. In this approach we first identified one or more metric and all the variables that are needed to calculate those metrics. Then useful ranges for the metrics are defined as well as possible (extreme) ranges for the variables. Then, one simply runs many cases with variables chosen at random from the possible ranges. By sorting out different levels of performance and plotting them against variables or clusters of variables, one can then quickly identify possible design spaces based on the model.

Applying Monte Carlo-based approach:

Performance metrics are defined as:

I ) Capacitive Compliance

2} Maximum allowable pressure.

Model variables and extreme ranges are defined as shown in the Table 1,

TABLE 1

Ten thousand (10,000), random cases were run over the variables in Table I and were plotted against the variables. The Monte Carlo results plotted against individual variables are shown in FIGS. 25A - 25E. The achievable ranges of capacitance compliance and maximum pressure are listed in Table 2.

Some of these plots shown in FIG.25 suggest certain variables are important and some metric values can be roughly tied to ranges of specific variables. However when certain variables are clustered together these ranges can be seen much more clearly as shown in FIGS.26A through 26D and Table 2. From FIGS. 26A through 26D is it is apparent that one variable cluster is particularly useful. The cluster, G*HAB/kb. is useful for identifying requirements for achieving capacittve compliance. Many structures with G*HAB/kb values ranging between 0.01 and 0.1 MPa*mm can produce structures with capacitive compliances ranging between 0.04 and 7.29 fF/gf. For structures with capacitive compliance greater than 7 fF/gf. G*HAB/kb must he less than 0.1 MPA*mm.

Equipment set-up: A set of four extruders were connected via insulated necktobes into a feedbiock and die similar to the manufacturing set-ups described in U.S. Patent Publication 20130009336. In this case the four separate material stream inputs were extruded into a series of siots with a repeating pattern shown in FIG. 27. Dimensions of the feed slots utilized for this technique can be varied significantly, but are frequently organized to provide individual flow channels that are 4 to 30 mils in width and height. The channel geometry as well as the flow rates and viscoelastic behavior at the melt process temperatures employed tor the individual polymer channels will have a strong influence on the final relative geometry (relative heights and widths; of the co-extruded structures. Typical melt train temperatures for the materials employed here ranged from 350 F to 500 F. Flow rate ratios between feed streams ranged from 1 :6 to 6:1 depending on the geometry desired.

The die is typically positioned at a height of one inch or less above a casting station (with a 60 °F 6" diameter stainless steel chill roll) upon which the web is quenched to solid form and then transported to a wind-up station. The take away speed of the casting station and winder tend to determine the final caliper of the web.

In the examples below a plurality of the How channels are positioned in the repeat, pattern as shown in FIG. 27. A first plurality of flow channels (feed stream A) is positioned adjacent to a second plurality of flow channels (feed stream B) in the horizontal direction. A third plurality of flow channels (feed stream C) is placed adjacent vertically (below) the second plurality of flow channels, while a fourth plurality of flow channels (feed stream D) is positioned horizontally adjacent to the third plurality of flow channels and vertically adjacent (below) the first plurality of flow channels. The flow channels of feed streams A and D were 4 mils in width, while the flow channels for feed streams B and C were 12 mils wide and the heights of the flow channels varied between 15 and 30 mils.

Examples 1 through 7: Silicone Polyoxamide having the chemical fbrnui!a I described on page 4 of US Patent 7,501.184 where R 1 is -CH3, R3 is -H, G is -CH₂CH2-. n is - 335, p = 1. Y is -CH₂CH₂CH2- (available from 3M company. St. Paul, Minnesota) was fed into feed stream A. while VISTAMAXX™ 3980 (Ethylene/PP copolymer) (available from ExxonMobil Chemical. Houston, Texas) and in some cases

VISTAMAXX™ 6202 was fed into feedstreams B, C, and D. Table 3 describes the materials, temperatures and flow rates of the samples that were generated.

Overall caliper represents the overall height of the film. A channel height and width describe the average height and width of the Silicone Polyoxamide in these films. A channel gap represents the average distance in-between the A channel structures. A channel % Proud refers to the estimated % (by area) of the A channel that protrudes above the patterned liner film. A channel width/height ratio is self-explanatory, while the A channel duty cycle simply calculates the width of the A channel divided by (the width of the A channel + the width of the gap between A channels ). The A channel shape is a crude description of the shape of the A channel structures formed during extrusion. The A channel transierrable with high fidelity column refers to the ease with which the lines of silicone polyoxamide are transferred from the structured liner article to a primed film, High fidelity implies complete or nearly complete transfer of the Silicone polyoxamide channels when these examples are subjected to 5 min of heat at 85* C after hand lamination prior to removal.

Examples 8 through 11: In these examples, feed stream A is fed by one ofthe elastomeric thermoplastics previously described and indicated in Table 3. Feed streams B, C.. and D are fed by PETg GN071. a eopolyester available from Eastman Chemical Company, Kingsport, TN.

Table 5 describes the materials, temperatures, and flow rates of the samples that would be generate examples 8 through 11.

It is anticipated that these co-extruded articles would yield easily removable elastomers from a structured copolyester liner.

Assembly of examples 12 thru 14: A structured peelable liner film (as described in examples #1 through #7) was brought in contact with a PET film with a first surface primed with a primer material as discussed above. Using a hand laminator and ordinary pressure to achieve reasonable surface-to-surface contact followed by a 5 minute heat soak in an 85 C oven enabled the elastomeric rows of Silicone Polyoxamide to be essentially completely removed from the structured peelable liner film. In a similar fashion, a second PET film with a first surface primed with the primer was attached to the elastomeric rows of Silicone Polyoxamide with hand lamination and an additional 85 *C heat treatment. Samples 12 and 13 were laminated to 2 - 2 mil PET films, while sample 14 was laminated to 2 - 1 mil PET films. All samples were subjected to additional elevated temperature for an additional amount of time. Table 6 highlights the geometry of the laminated samples as well as some of the performance results from tests performed on these samples:

20

25

30

35

Article height refers to the total article height (including the PET films), the height of each PET film is called out in the PET film height column. Heat soak temp and time represent the amount of additional time a sample spent in an oven with an elevated temperature, Elastomeric structure height and width describe the average height and width of each Silicone Polyoxamide row (which are largely rectangular after lamination). The gap between structures represents the average gap width between the edges of the structures. T he elastomer width/height ratio and elastomer content are calculations which are previously described in this document

Capacilive compliance is a measure of the change in capacitance per force exerted on the sample. To effectively measure this, one needs to apply a conductive coating to the top and bottom surfaces of the laminated structure, and then measure the change in capacitance vs. compressive force.

5N Mechanical Compliance is a calculation of how a 25mm disc of the laminated sample has compressed after 5N of compressive force has been applied to it. This is conducted at 1 Hz on an Ares G2 at 20 °C.

180 ° peel strength is conducted using an Imass SP-2100 test unit, 1 " wide by 6" long strip. 5 kg load cell, peel rate at 12 ia½in. Performance information for test structures made from lamination transfer film #1 :

Peel force (standard ISO degree peel) > 300 grams/inch

5N Mechanical compliance (defined by force required vs. deflection) 50 g/nm Capacitive compliance > 1 1F/gf Items discussed herein include:

Item 1. A lamination transfer film comprising:

multiple discrete rows of an elastomeric material with spaces separating adjacent rows: and

a peelable liner disposed over the rows and in the spaces between the adjacent rows, wherein the peelable liner is not substantially adhered to the elastomeric material.

Item 2. The lamination transfer film of item 1, wherein the rows of elastomeric material have one of a semicircular cross sectional shape, a rectangular cross sectional shape, a triangular cross sectional shape, a truncated triangular cross sectional shape, and an hourglass cross sectional shape.

Item 3. The lamination transfer film of item 1. wherein the elastomeric material comprises a si licone thermoplastic or Iherrnoset material. item 4. The lamination transfer film of item 1. wherein the elastomeric material is silicone polyoxamide. item 5. The lamination transfer film of item 1. wherein the elastomeric material comprises at least one of a olefin copolymer and a styrene block copolymer.

Item 6. The lamination transfer film of item 1. wherein a shear modulus of the elastomeric material is less than about 500 MPa.

Item 7. The lamination transfer film of item 6, wherein a product of the shear modulus and undeformed height of the elastomeric rows is less than 13 MPa* mm.

Item 8. The lamination transfer film, of item 6. wherein a change in the shear modulus is less titan about 50% over a temperature range of -20 C to 60 C.

Item 9. The lamination transfer film of item 1. wherein the elastomeric material has a glass transition temperature of less than about ·· 30 C. Hem 10. The lamination transfer film of item 1 , wherein the elastomeric material has a tan delta of less than or equal to about 0.5.

Item 1.1. The lamination transfer film of item 1, wherein the pee!ab!e liner is a

thermoplastic material.

Item 12. The lamination transfer film of item 1, wherein the peelable liner is an olefin. item 13. The lamination transfer film ol item J. wherein the peelable liner comprises polypropylene or polyethylene. Item 14. The lamination transfer film of item 1, wherein attachment of the peelabie liner to the features is characterized by a peel force and the peel force is less than about 100 grams/inch.

5

Item 15. The lamination transfer film of item 1, wherein the peelabie liner includes a release additive. item 16. The lamination transfer film of item 1, wherein each row of elastomeric material 0 has a height and a width, and wherein the ratio of the width to the height is greater than about 0.3 and less than about 10.

Item 17. The lamination transfer film of item 1, wherein a height of the rows is in a range of about 0.1 mm to about 10 mm.

5

item 18. The lamination transfer film of item 1, wherein width of the rows is between about 50 μm to about 400 μm. hem 19, The lamination transfer film of item 1, wherein width of the spaces between 20 adjacent rows is about 50 μm to about 400 urn.

Item 20. The lamination transfer film of item 1 , wherein elastomeric content of the lamination transfer film has a range of 5% to 99%.

25 hem 21. The lamination transfer film of item 1 , wherein elastomeric content of the

lamination transfer film has a range of 25% to 75%. hem 22. The lamination transfer film of item 21, wherein the elastomeric content is about 50%.

30

Item 23. The lamination transfer film of item 21, wherein the elastomeric content varies with distance. Item 24. The lamination transfer film of item ) . wherein tree surfaces of the elastomeric rows protrude past free surfaces of the peelabie liner.

Item 25. A method comprising coextruding an elastomeric material and a liner material to form a lamination transfer film having multiple discrete rows of elastomeric material with spaces separating adjacent rows and a peelabie liner of the liner material disposed over the rows of elastomeric material and in the spaces between adjacent rows and wherein the peelabie liner is not substantially adhered to the elastomeric material Item 26. The method of item 25, further comprising:

placing the lamination transfer film onto a primer layer such that free surfaces of the rows of elastomeric material are in contact with the primer layer: and

removing the peelabie liner leav ing the rows of elastomeric material affixed to the primer layer.

Item 27. The method of item 25 further comprising applying the primer layer to a surface of a first component before placing the lamination transfer film on the primer layer. item 28. The method of item 27 further comprising after removing the peelabie liner from the rows of elastomeric material, placing surfaces of the rows of elastomeric material previously covered by the peelabie liner onto a primer layer on a second component.

Item 29. The method of item 28, wherein the first and second components comprise first and second barrier films, first and second adhesive layers or first and second electrodes.

Item 30. The method of item 26. wherein placing the lamination transfer film onto the primer layer comprises placing multiple sections of the lamination transfer film onto the primer layer of the first component in a tiled manner. Item 31. The method of item 30 wherein the rows of elastomeric material of the multiple sections are rotated to different angles relative to one another.

Item 32. The method of claim 25, wherein coextruding the elastomeric material and the liner material comprises selecting flowrates of the elastomeric material and the liner materia! during the cocxtruding so that free surfaces of the rows ofelastomerie material extend beyond the peelabie liner.

Item 33. A method, comprising:

5 forming a structured liner that includes channels;

disposing an eiastomeric material into channels of a structured liner; and applying at least one of pressure and heat to the eiastomeric material to form a lamination transfer film comprising multiple discrete rows of an eiastomeric material with spaces separating adjacent rows and a peelabie liner disposed over the rows and in the spaces between the adjacent rows, wherein the peelabie liner is not substantially adhered to the eiastomeric material.

Item 34. A device, comprising:

a first component;

5 a first primer layer disposed on the first components:

a second component;

a second primer layer disposed on the second component: and

multiple discrete rows of an eiastomeric material with spaces separating adjacent rows, first surfaces of the rows of eiastomeric material adhered to the first primer layer 20 and opposing second surfaces of the rows ofelastomerie material adhered to the second primer layer. item 35. The device of item 34, wherein mechanical compliance of the device is between about 0.02 and about 0.5 mm/MPa.

5

Item 36. The device of item 34, wherein the first and second components comprise first and second electrodes and capacitance between the first and second electrodes is a function of a force applied normal to the electrodes. 0 Item 37. The device of item 36, wherein capacitive compliance of the device is between about 0.5 to about 100 fF/g.

Item 38. The device of item 36, wherein capacitive compliance of the device is greater than about 2 fF/g. Unless otherwise indicated, all numbers expressing quantities, measurement of properties and so forth used in the specification and claims are to he understood as being modified by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and claims are approximations that can vary depending on the desired properties sought to be obtained by those skilled in the art. utilizing the teachings of the present application.

Various modifications and alterations of the embodiments discussed above will be apparent to those skilled in the art. and it should be understood that this disclosure is not limited to the illustrative embodiments set forth herein. The reader should assume ihat features of one disclosed embodiment can also be applied to all other disclosed

embodiments unless otherwise indicated. It should also be understood that all U.S.

patents, patent applications, patent application publications, and other patent and non- patent documents referred to herein are incorporated by reference, to the extent they do not contradict the foregoing disclosure.

Claims

1. A lamination transfer film comprising;

multiple discrete rows of an elastorneric material with spaces separating adjacent 5 rows; and

a peelable liner disposed over the rows and in the spaces between the adjacent rows, wherein the peelable liner is not substantially adhered to the elastorneric material.

2. The lamination transfer film of claim 1 , wherein the rows of elastorneric material 0 have one of a semicircular cross sectional shape, a rectangular cross sectional shape, a triangular cross sectional shape, a truncated triangular cross sectional shape, and an hourglass cross sectional shape.

3. The lamination transfer film of claim 1. wherein the elastorneric material

5 comprises a silicone thermoplastic or thermoset material .

4. The lamination transfer film of claim 1. wherein the elastorneric material is silicone polyoxamide,

20 5. The lamination transfer film of claim 1 , wherein the elastorneric material

comprises at least one of a olefin copolymer and a styrene block copolymer.

6. The lamination transfer film of claim 1. wherein a shear modulus of the elastorneric material is less than about 50Q MPa.

25

7. The lamination transfer film of item 6, wherein a product of the shear modulus and undeformed height of the elastorneric rows is less than 13 MPa*mm.

8. The lamination transfer film of claim 6, wherein a change in the shear modulus is 30 less than about 50% over a temperature range of -20 C to 60 C.

9. The lamination transfer film of claim 1. wherein the elastorneric material has a glass transition temperature of less than about - 30 C.

10. The lamination transfer film of claim 1 , wherein the eiasiomeric material has a tan delta of less than or equal to about 0,5.

11. The lamination transfer film of claim 1 , wherein the peelable liner is a

thermoplastic material.

12. The lamination transfer film of claim 1 , wherein the peelable liner is an olefin.

13. The lamination transfer film of claim 1 , wherein the peelable li ner comprises polypropylene or polyethylene.

14. The lamination transfer film of claim 1. wherein attachment of the peelable liner to the features is characterized by a peel force and the peel force is less dian. about 100 grams/inch.

15. The lamination transfer film of claim 1. wherein the peelable liner includes a release additive.

16. The lamination transfer film of claim } , wherein each row of eiastomeric material has a height and a width, and wherein the ratio of the width to the height is greater than about 0.3 and less than about 10.

17. The lamination transfer film of claim 1 , wherein a height of the rows is in a range of about 0.1 mm to about 10 mm.

18. The lamination transfer film of ciaim 1. wherein width of the rows is between about 50 μm to about 400 μm.

19. The lamination transfer film of claim 1. wherein width of the spaces between adjacent rows is about 50 μηι to about 400 μm.

20. The lamination transfer film of claim 1. wherein elasiomeric content of the lamination transfer film has a range of 5% to 99%.

21. The lamination transfer film of claim 1 , wherein elastomeric content of the lamination transfer film has a range of 25% to 75%

22. The lamination transfer film of claim 21. wherein the elastomeric content is about 50%.

23. The lamination transfer film of claim 21. wherein the elastomeric content varies with distance.

24. The lamination transfer film of claim 1. wherein free surfaces of the elastomeric rows protrude past tree surfaces of the peelable liner.

25. A method comprising coextruding an elastomeric material and a liner material to form a lamination transfer film having multiple discrete rows of elastomeric material with spaces separating adjacent rows and a peelable liner of the liner material disposed over the rows of elastomeric material and in the spaces between adjacent rows and wherein the peelable liner is not substantially adhered to the elastomeric material.

26. The. method of claim 25, further comprising:

placing the lamination transfer film on a primer layer such that free surfaces of the rows of elastomeric material are in contact with the primer layer; and

removing the peelable liner leaving the rows of elastomeric material affixed to the primer layer.

27. The method of claim 26 further comprising applying the primer layer to a surface of a first component before placing the lamination transfer film on the primer layer.

28. The method of claim 27 further comprising after removing the peelable liner from the rows of elastomeric material, placing surfaces of the rows of elastomeric material previously covered by the peelable liner onto a primer layer on a second component.

29. The method of claim 28, wherein the first and second components comprise first and second barrier films, first and second adhesive layers or first and second electrodes.

30. The method of claim 26, wherein placing the lamination transfer film onto the primer layer comprises placing multiple sections of the lamination transfer film onto the primer layer of the first component in a tiled manner.

31. The method of claim 30, wherein the rows of elastomerie material of the multiple sections are rotated to different angles relative to one another.

32. The method of claim 25, wherein coextruding the elastomerie material and the liner material comprises selecting flowrates of the elastomeric material and the liner material during the coextruding so that free surfaces of the rows of elastomerie material extend beyond the peelable liner.

33. A method, comprising:

forming a structured liner that includes channels;

disposing an elastomerie material into channels of a structured liner; and applying at least one of pressure and heat to the elastomerie material to form a lamination transfer film comprising multiple discrete rows of an elastomerie material with spaces separating adjacent rows and a peelable liner disposed over the rows and in the spaces between the adjacent rows, wherein the peelable liner is not substantially adhered to the elastomerie material.

34. A device, comprising:

a first component;

a first primer layer disposed on the first components;

a second component;

a second primer layer disposed on the second component; and

multiple discrete rows of an elastomerie material with spaces separating adjacent rows, first surfaces of the rows of elastomerie material adhered to the first primer layer and opposing second surfaces of the rows of elastomerie material adhered to the second primer layer.

35. The device of claim 34, wherein mechanical compliance of the device is between about 0.02 and about 0.5 mm/MPa.

36, The device of claim 34. wherein the first and second components comprise first and second electrodes and capacitance between the first and second electrodes is a function of a force applied normal to the electrodes.

37. The device of claim 36, wherein capacitive compliance of the device is between about 0.5 to about 100 fF/g.

38. The device of claim 36, wherein capacitive compliance of the device is greater than about 2 fF/g.