U.S. patent application number 11/571748 was filed with the patent office on 2008-12-11 for novel packaging solution for highly filled phase-change thermal interface material.
Invention is credited to Robert A. Rauch.
Application Number | 20080302064 11/571748 |
Document ID | / |
Family ID | 35839576 |
Filed Date | 2008-12-11 |
United States Patent
Application |
20080302064 |
Kind Code |
A1 |
Rauch; Robert A. |
December 11, 2008 |
Novel Packaging Solution for Highly Filled Phase-Change Thermal
Interface Material
Abstract
A packaging system, packaging method and method of depositing a
thin layer of material at a desired location upon a substrate, and
in particular a layer of thermally-conductive phase change material
at the interface between a heat-dissipating component and heat sink
coupled therewith. The packaging comprises a thin layer of material
sandwiched between a first base liner and a second top liner. A
segment of tape is adhesively bound to the top liner and preferably
includes a graspable portion, such as a tab, to enable the same to
pull the top liner away from the material to thus leave the layer
of material deposited upon the substrate.
Inventors: |
Rauch; Robert A.; (Dove
Canyon, CA) |
Correspondence
Address: |
LOCTITE CORPORATION
1001 TROUT BROOK CROSSING
ROCKY HILL
CT
06067
US
|
Family ID: |
35839576 |
Appl. No.: |
11/571748 |
Filed: |
July 8, 2005 |
PCT Filed: |
July 8, 2005 |
PCT NO: |
PCT/US05/24343 |
371 Date: |
January 8, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60587453 |
Jul 13, 2004 |
|
|
|
Current U.S.
Class: |
53/329 ;
257/E23.088 |
Current CPC
Class: |
H01L 2924/0002 20130101;
H01L 23/427 20130101; H01L 2924/00 20130101; H01L 21/6835 20130101;
H01L 2924/3025 20130101; H01L 2924/0002 20130101 |
Class at
Publication: |
53/329 |
International
Class: |
B65B 7/28 20060101
B65B007/28 |
Claims
1. A packaging system for a layer of material comprising: a) a base
liner, said layer of material being formed upon said base liner; b)
a top liner disposed substantially over said layer of material
deposited upon said base liner; and c) a tape segment adhesively
bound to at least a portion of said top liner.
2. The system of claim 1 wherein said layer of material comprises a
thermally-conductive composition.
3. The system of claim 2 wherein said thermally-conductive
composition possesses phase-change properties.
4. The system of claim 1 wherein said segment of tape has a tab
formed thereon.
5. The system of claim 1 wherein said base liner and said top liner
comprise paper release liners.
6. The system of claim 1 wherein said layer of material and said
top liner define a length and a width and said tape extends across
a respective one of said length and width defined by said layer of
material and top liner.
7. The system of claim 6 wherein said layer of tape further extends
to and is adhesively bound to said base liner.
8. The system of claim 7 wherein said tape is adhesively bound to
said base liner at a point beyond the peripheral edge defined by
said layer of material and said top liner.
9. The system of claim 1 wherein said layer of material comprises a
thermally-conductive composition having a thickness of
approximately 8 mil.
10. A method for packaging a layer of material comprising the
steps: a) providing a base liner; b) depositing said layer of
material upon said base liner provided in step a); c) placing a top
liner over said layer of material deposited upon said base liner;
and d) rolling said base liner and top liner with layer of material
disposed therebetween such that said layer of material assumes a
desired thickness; and e) adhesively attaching a segment of tape to
said top liner positioned over said layer of material in step
c).
11. The method of claim 10 wherein in step b), said layer of
material comprises a thermally-conductive composition; and wherein
in step d), said layer is formed to have a thickness of
approximately 8 mil.
12. The method of claim 11 wherein in step b), said
thermally-conductive material is a phase-change material.
13. The method of claim 10 wherein in step d), said tape segment is
adhesively attached to both said top liner and said base liner.
14. The method of claim 10 wherein in step d), said layer is formed
to have a specific surface area.
15. The method of claim 14 wherein said layer of material is formed
to have a generally square shape.
16. The method of claim 15 wherein said generally square shape is
approximately one inch by one inch.
17. The method of claim 10 wherein following step e) said method
further comprises the step: a) forming a tab upon said segment of
tape.
18. The method of claim 17 wherein said tab is formed by folding a
portion of said tape segment upon itself.
19. A method of applying a pre-packaged layer of material upon a
desired portion of a substrate comprising the steps: a) providing a
pre-packaged layer of material, said pre-packaged layer of material
comprising: i) a base liner and a top liner, said layer of material
being disposed between said base liner and top liner; and ii) a
tape segment adhesively bound to at least a portion of said top
liner; b) removing said base liner from said packaging such that a
portion of said layer of material is exposed; c) placing said
exposed layer of material in step b) upon the desired portion of
said substrate; and d) pulling said tape with said top liner
adhesively bound thereto away from said layer of material
positioned upon said substrate in step c).
20. The method of claim 19 wherein in step a), said layer of
material comprises a thermally-conductive material and wherein in
step c), said substrate comprises a heat sink.
21. The method of claim 20 wherein said thermally-conductive
material comprises a phase change material.
22. The method of claim 19 wherein in step a), said base liner and
said top liner comprise paper release liners.
23. The method of claim 19 wherein step c) further comprises
adhesively attaching a portion of said tape segment to said
substrate.
24. The method of claim 10 wherein said method further comprises
the step: a) forming said packaged layer of material in step d) as
a roll.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] Compositions, systems and methods for facilitating the
transfer of heat from a heat dissipating component to a heat sink
are well-known in the art. Exemplary of such compositions, methods
and systems include those disclosed and claimed in U.S. Pat. No.
5,904,796, issued May 18, 1999, entitled ADHESIVE THERMAL INTERFACE
& METHOD OF MAKING THE SAME; U.S. Pat. No. 5,912,805, issued
Jun. 15, 1999, entitled THERMAL INTERFACE WITH ADHESIVE; U.S. Pat.
No. 6,483,707, issued Nov. 19, 2002, entitled HEAT SINK &
THERMAL INTERFACE HAVING SHIELDING TO ATTENUATE ELECTROMAGNETIC
INTERFERENCE; U.S. Pat. No. 6,616,999, issued Sep. 9, 2003,
entitled PREAPPLIABLE PHASE CHANGE THERMAL INTERFACE PAD; U.S. Pat.
No. 6,652,705, issued Nov. 25, 2003, entitled GRAPHITIC ALLOTROPE
INTERFACE COMPOSITION AND METHOD OF FABRICATING THE SAME; and U.S.
Pat. No. 6,672,378, issued Jan. 6, 2004, entitled THERMAL INTERFACE
WAFER & METHOD OF MAKING & USING THE SAME, the teachings of
which are expressly incorporated herein by reference.
[0004] Among such products and systems that are commercially
available include those products sold under the trademarks
POWERSTRATE, THERMSTRATE, ISOSTRATE, MCM-STRATE, EMI-STRATE,
THERMSTRATE TC and POWERFILM, all of which are produced by Power
Devices, Inc. of Laguna Hills, Calif., which is a subsidiary of
Henkel, Inc. of Gulph Mills, Pa.
[0005] Transferring heat away from a heat-dissipating component,
which typically comprises microprocessors and other electronic
componentry, is essential for many electronic devices to function
properly. To the extent heat is not removed, such electronic
componentry will operate sub-optimally and can become damaged,
sometimes irreparably. The aforementioned compositions and systems
address such issue by facilitating the ability to draw heat away
from the heat generating source to a heat dissipating object, which
typically comprises a heat sink. With respect to the latter, heat
sinks are typically formed from a material having excellent heat
conducting properties, such as aluminum, that are provided with an
enlarged surface area, typically defined by protuberances, fins, or
other like materials that are operative to dissipate the heat
transferred thereto into the surrounding air. With respect to the
latter, fans are frequently utilized to thus provide adequate air
circulation and thus facilitate the dissipation of heat.
[0006] The aforementioned compositions, systems and methods for
transferring heat are typically deployed at the juncture between
the heat dissipating component and the heat sink. In this regard,
such heat transfer materials are typically operative to ensure
proper mechanical contact between the heat dissipating component
and the heat sink coupled therewith insofar as it widely recognized
that mechanical contact between such componentry greatly
facilitates the ability of heat to be transferred thereacross.
[0007] To that end, it is widely recognized that phase change
materials, such as those disclosed in U.S. Pat. Nos. 5,904,796;
5,912,805; 6,483,707; 6,616,999; 6,652,705; and 6,672,378 are
exceptionally effective to facilitate in the transfer of heat
across the thermal interface. Such phase change materials, which
are formulated to remain solid at room temperature but liquefy at
temperatures at or near the operating temperature of the electronic
componentry to which the material is utilized, offer the advantage
of ensuring mechanical contact between the heat dissipating
component and heat sink during operation of the device, but
thereafter solidify so that the same remains within a discreet area
at the interface between the electronic component and heat sink.
The latter aspect is particularly important insofar as the property
of such phase change material to remain solid greatly facilitates
the ability of such materials to be applied at the desired juncture
between the heat dissipating component and heat sink.
[0008] Despite the ideal properties of phase change materials to
facilitate the transfer of heat, however, are drawbacks associated
with the ability to package, ship and apply such materials at the
interface between the electronic component and heat sink to be
coupled therewith. Specifically, most phase change materials are
formed to have as minimal thickness as possible in order to
maximize the transfer of heat and thus are very fragile. Moreover,
due to the phase change property of such materials, the same are
easily torn or ablated during application, and thus can be easily
damaged or improperly applied.
[0009] To address such shortcomings, most phase change materials
are typically mounted upon a substrate that facilitates the ability
of such materials to be manufactured, shipped and ultimately
secured at the interface between a heat dissipating component and a
heat sink. The use of a substrate, however, is well-known to impede
the flow of heat by introducing additional thickness at the
interface, as well as by introducing a separate layer of material
that extends across the path of heat flow. As a consequence, the
advantages of utilizing a substrate can and frequently are
outweighed by the impediment to heat flow that such structures
cause.
[0010] As such, there is a substantial need in the art for a new
packaging system and method that is operative to enable thin layer
materials, and in particular phase change materials operative to
facilitate the transfer of heat from a heat dissipating component
to a heat sink, to be packaged, shipped and ultimately applied to
the interface between a heat dissipating component and heat sink
that preserves the shape and integrity of material, allows for
extremely accurate and reproducible application, and, in the
context of thermally conductive compositions, eliminates the need
for a substrate to be deployed to position such materials at the
interface between the heat dissipating component and the heat sink.
There is likewise a need for such a system and method that is of
extremely simple construction, low cost, simplistic to use, and can
be readily implemented utilizing existing technology. There is
additionally a need in the art for such a system and method that
can be used with virtually any type of phase change material, as
well as any other types of films and layers of materials that must
be precisely fabricated, shipped and applied.
BRIEF SUMMARY OF THE INVENTION
[0011] The present invention specifically addresses and alleviates
the above-identified deficiencies in the art. In this regard, the
present invention is directed to packaging systems and methods for
packaging a thin layer of material, as well as a method for
applying such layer of material at a discrete location upon a
substrate. The present invention is particularly suited for the
packaging and application of phase change materials, and in
particular phase change materials for facilitating the transfer of
heat from a heat dissipating component to a heat sink.
[0012] According to a preferred embodiment, the thin layer of
material sought to be packaged is disposed between a first base
liner and a second top liner such that the layer of material is
confined or sandwiched between the first base liner and second top
liner. Preferably, the layer of material is rolled into a film
contained between the base liner and top liner. To the extent
desired, the layer of material with top layer positioned thereover
may be cut to have a desired shape or footprint to thus match the
dimensions of a given thermal interface. For example, it is
contemplated that the layer of material with top liner formed
thereon may be cut to assume one inch by one inch square
shapes.
[0013] Once so formed, an elongate segment of tape is adhesively
attached across all or a portion of the top liner, and preferably
is provided with a length sufficient to enable the tape segment to
extend over and across the top liner such that at least one or both
free ends of the tape can adhesively attach to the base liner.
Preferably, the layer of tape will be provided with a tab or some
other mechanism. In a preferred embodiment, the base liner and
layer of tape will extend beyond the top liner and layer of
material sandwiched therebetween such that the layer of tape will
come into contact with and adhesively bind to the base liner. In
such preferred embodiment, the layer of material disposed between
the top and base liners will in essence be encapsulated to thus
provide a further degree of protection to the layer of material
that will ultimately be deposited at the thermal interface.
[0014] In order to apply the layer of material, the user will
initially remove the base liner to thus expose the layer of
material on one side. To that end, the base liner may simply be
peeled away from the layer of material as per conventional
practice. In those embodiments deploying packaging whereby the
layer of tape and base liner extend over and encapsulate the top
liner and layer of material, the tape and base liner will initially
be removed from one another.
[0015] Once the layer of material is exposed, the same is deposited
directly upon the substrate, namely, that portion of the heat sink
defining the thermal interface. Such application will typically
involve merely placing the exposed layer of material at a target
site upon a substrate, namely, the thermal interface, and
thereafter rapidly pulling the tape adhesively bound to the top
layer away from the substrate. In a more highly preferred method,
the system will utilize a piece of tape extending over the top
liner and layer of material disposed there underneath with the
extended portion of tape being utilized to first tape the exposed
layer of material at a target site upon the substrate. By gently
pulling the tape upward, the top liner adhesively bound thereto
will peal away from the layer of material, with the material
staying at rest and remaining adhered to the interface due to its
much greater inertia than the tape and top liner. In this regard,
pulling on the tape which is adhesively attached to the interface
creates a resistive force opposite to the pull. At the point where
the adhesive stops, the pull continues and the resistive force
stops, resulting in a rate of change of acceleration being imparted
to the top liner through the tape. The resulting acceleration of
the top liner is not transferred to the material due to incomplete
adhesion between the material and the top liner. The material stays
at rest and remains on the interface surface while the top liner is
removed for final assembly. As a consequence, the layer of material
is precisely and uniformly put into position quickly and easily,
and further, advantageously dispenses with the need for any type of
substrate to properly position such material.
[0016] It is therefore an object of the present invention to
provide a packaging system, method of packaging, and method of
applying a layer of material at a desired location upon a
substrate, and in particular a layer of phase change material
operative to facilitate the transfer of heat from a
heat-dissipating component to a heat sink, that is exceptionally
more reliable, of simple construction, and substantially faster and
easier to utilize than prior art packaging and application
techniques.
[0017] Another object of the present invention is to provide
packaging system, method of packaging, and method of applying a
layer of material at a desired location upon a substrate, and in
particular a layer of phase change material operative to facilitate
the transfer of heat from a heat-dissipating component to a heat
sink, that provides for better product protection and substantially
conserves the amount of material utilized to facilitate the
transfer of heat than prior art practices.
[0018] Still further objects of the present invention are to
provide a packaging system, method of packaging, and method of
applying a layer of material at a desired location upon a
substrate, and in particular a layer of phase change material
operative to facilitate the transfer of heat from a
heat-dissipating component to a heat sink, that is of simple
construction, can be readily implemented utilizing known
manufacturing techniques and materials, and substantially minimizes
labor associated with the application of heat-transfer compositions
to the interface between a heat-dissipating component and heat sink
coupled therewith.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] These as well as other features of the present invention
will become more apparent upon reference to the drawings.
[0020] FIG. 1 is a cross-sectional view of a layer or pad of
material for facilitating the transfer of heat as contained within
a package constructed in accordance with the preferred embodiment
of the present invention.
[0021] FIG. 2 is the cross-sectional view of FIG. 1 wherein the
lower base liner of the packaging is shown removed.
[0022] FIG. 3 is a cross-sectional view of a heat sink depicting a
portion of the layer of material and packaging in FIG. 2 applied
thereon.
[0023] FIG. 4 is the cross-sectional view of FIG. 3 wherein a
segment of tape and upper liner of the packaging are shown being
removed with the layer of material remaining in place upon the heat
sink.
[0024] FIG. 5 is a top view of a dispensing system for use in
dispensing the packaged materials of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0025] The detailed description set forth below is intended as a
description of the presently preferred embodiment of the invention,
and is not intended to represent the only form in which the present
invention may be constructed or utilized. The description sets
forth the functions and sequences of steps for constructing and
operating the invention. It is to be understood, however, that the
same or equivalent functions and sequences may be accomplished by
different embodiments and that they are also intended to be
encompassed within the scope of the invention.
[0026] Referring now to the figures, and initially to FIG. 1, there
is shown a preferred packaging system 10 for a thin layer of
material 14, the latter preferably comprising a single layer or
film of thermally-conductive material having phase change
properties. In this regard, it is expressly contemplated that
packaging 10 will be particularly well suited to facilitate the
manufacturing, shipping, handling and ultimate application of such
thermally-conductive material, such as 14, that has not heretofore
been available. Along these lines, it is expressly contemplated
that the packaging 10 will be exceptionally well-adapted for use
with certain thermally-conductive phase change materials produced
by Power Devices, Inc., and in particular its Powerstrate Xtreme
phase change materials.
[0027] As illustrated, the packaging comprises a layer of material
14 sandwiched between a first base liner 12 and top liner 16.
Preferably, such sandwich-type arrangement is formed by depositing
the layer of material 14 between liners 12, 16, the latter of which
preferably comprising paper release liners, such that the layer is
ultimately formed to have a thickness of between approximately 2 to
20 mil. with approximately 8 mil. being preferred. In a highly
preferred embodiment, the base liner will comprise 54 lb. zero
release paper and the top liner will comprise 42 lb. zero release
paper. To facilitate the rolling of such compound, such compound is
preferably heated to a temperature of approximately 60.degree. C.
In this regard, because it is expressly contemplated that such
layer of material 14 will comprise a thermally-conductive
phase-change material, it is believed that such manufacturing
process is preferred insofar as such material is inherently tacky
and it is desired that the same be formed as a free standing film
having a uniform thickness. As will be readily appreciated,
however, it is contemplated that all other types of manufacturing
processes whereby the layer of material 14 can be formed to assume
the sandwich-type configuration between liners 12, 16, whether it
be by first depositing the layer of material 14 upon base liner 12
and thereafter covering the same with top liner 16, should be
deemed to fall within the scope of the present invention.
[0028] In the embodiment depicted, top liner 16 will be formed to
have the same dimensions as layer 14 such that both items 14, 16,
will define a continuous peripheral edge. In this respect, it is
contemplated that the layer 14 and top liner 16 may be selectively
cut or formed upon base liner 12 according to a particular shape or
footprint as may be desired for a given application. For example,
layers have been formed to fit heat sink interfaces as big as
5''.times.6''. Alternatively, it is contemplated that layer 14 and
top liner 16 may be cut to assume specific types of geometric
shapes, and in particular generally square-type shapes of one inch
by one inch, as is typical for the sizes of most thermal interfaces
currently in use.
[0029] Extending across top layer 16 is a strip or segment of
adhesive tape 18, the latter being adhesively bound to top layer
16. In the preferred embodiment shown, the segment of tape 18 will
be provided such that the same extends over the width or length of
the layer of material 14 and top layer 16, as illustrated by the
segments 18a, 18b, respectively. According to such embodiment, the
tape 18, via such extended portions 18a, 18b, can adhesively bind
to base liner 12. Advantageously, by extending completely about the
layer of material 14, the bottom liner 12 and segment of tape 18
cooperate to encapsulate and protect the layer 14 contained
therewithin.
[0030] In a preferred although optional embodiment, at least one
portion of the tape 18 will be provided with a tab or other type of
graspable portion that can enable the tape 18 to be pulled away,
discussed more fully below. In the embodiment shown, tape segment
18 is provided with first and second tabs 20a, 20b that can be
utilized to facilitate both placement of the layer of material 14
and removal of the tape segment 18. In this respect, it is
contemplated that such tabs 20a, 20b, may be defined merely by
folding the ends of the tape upon itself with the adhesive side of
the tape binding with itself and the outer non-adhesive side
defining the tab 20a, 20b. With respect to preferred types of tape
that may be utilized, it is presently contemplated that
conventional shipping tape such as SMI Polyfilm, P/N 1864000685,
15/8'' wide, 1 mil thick. Other commercial alternatives include
Scotch #810 Magic Tape and Intertape 1100, #F4218, 2'' wide, 2 mil
thick.
[0031] While in its packaged state, as depicted in FIG. 1, the
layer of material 14 can be shipped and handled as needed.
Advantageously, such packaged condition enables the free standing
layer of material 14 to be protected and maintain its shape and
thickness without the need of a substrate. Typically, most layers
of phase change materials must either be formed upon substrates or
otherwise provided in block form for subsequent application via
excoriation and the like. In this regard, there has not heretofore
been available a method for packaging a single layer of film that
further facilitates the ability of the same to be directly applied
to a thermal interface.
[0032] With respect to this latter aspect of the invention, there
is shown in FIGS. 2-4 the sequential steps for applying the layer
of material 14 as secured within packaging 10. Referring initially
to FIG. 2, the initial step in applying the layer of material 14
begins with the removal of base liner 12, which can be accomplished
by simply peeling away base liner 12 from the layer of material 14.
In this respect, it is well-known in the art that layers 12, 14 may
be formulated such that layer of material 14 adheres more strongly
to the top layer 16, as opposed to base layer 12. The ability to
fabricate and/or select liners 12, 14 to achieve that end is
readily understood within the art.
[0033] Once the base liner 12 has been removed, as shown in FIG. 2,
the exposed layer of material 14 with upper layer 16 and tape
segment 18 coupled therewith are selectively positioned at a
desired area upon the substrate, namely, a heat sink 22, as shown
in FIG. 3. To that end, the layer of material 14 need only be
lightly compressed upon the interface. In this regard, the layer 14
will be caused to stick in place due to the tacky nature of such
compositions. Advantageously, and unlike other prior art methods,
there is no requirement during application of layer 14 that the
heat sink 22 be either preheated or otherwise heated and thereafter
cooled during application.
[0034] Once positioned upon the substrate, a tab (or a respective
one of the tabs, such as 20b as shown), is gently pulled upward to
thus cause the layer of material 14 to remain in position at the
desired location upon the heat sink 22, as shown in FIG. 4. In this
regard, it is presently understood that the pulling of tape segment
18 and top liner 16 adhesively bound thereto causes top liner 16 to
readily remove from layer 14 due to the latter's greater inertia
and incomplete adhesion to the top liner 16. Such forces, coupled
with the sticky nature of the phase change material, causes the
layer of material 14 to adhere to the heat sink as opposed to
remaining stuck upon top liner 16. Once the layer of material 14 is
deposited in the desired position, the thermal pathway can be
completed whereby the heat-dissipating componentry is coupled to
the heat sink 22 with the layer of material 14 being disposed
therebetween.
[0035] Referring now to FIG. 5, there is shown another aspect of
the present invention, namely, a dispensing system for use in
distributing and applying the packaged materials of the present
invention. As shown, the packaged product will be formed as a roll
24, as per conventional practice of shipping and storing thermally
conductive materials. In this regard, and as is illustrated, such
rolled products are typically mounted upon a base 26 having one or
more dowels 28 distributed thereabout. The dowels 28 are operative
to make a segment of the rolled heat transfer material accessible
such that a desired length of material can be cut from the roll of
tape. Such an arrangement advantageously allows for rapid access to
the thermally conductive material to thus expedite the application
process.
[0036] Additional modifications and improvements of the present
invention may also be apparent to those of ordinary skill in the
art. Thus, the particular combination of parts and steps described
and illustrated herein is intended to represent only certain
embodiments of the present invention, and is not intended to serve
as limitations of alternative devices and methods within the spirit
and scope of the invention.
* * * * *