COMPOSITE FOR HEAT-DISSIPATING FILM

Information

  • Patent Application
  • 20110054104
  • Publication Number
    20110054104
  • Date Filed
    August 26, 2009
    15 years ago
  • Date Published
    March 03, 2011
    13 years ago
Abstract
The invention provides a composite for coating and sputtering a heat-dissipating film. The composite contains silicon carbide of 25˜30 wt. % (weight percentage), teflon-based resin of 9-11 wt. %, and diluted ketones/alcohols-group material of 60˜65 wt. %. These components are mixed and blended to be capable of being coated, sputtered, and cured into a heat-dissipating film of a specific thickness. As such, the heat-dissipating performance could be conveniently enhanced. There is no need to rely on heat-sinking fins of large surface area. The production cost is reduced, recycling is easier, and the highly contaminating anodizing treatment could be avoided, while the robustness against erosion and harsh weather is still maintained.
Description
TECHNICAL FIELD OF THE INVENTION

The present invention generally relates to a composite for coating and sputtering on an object for enhanced heat-dissipating performance so that there is no need to rely on heat-sinking fins of large surface area, the production cost is reduced, recycling is easier, and the highly contaminating anodizing treatment could be avoided without sacrificing the robustness against erosion and harsh weather.


DESCRIPTION OF THE PRIOR ART

Computer processors, high-brightness light emitting diode (LED) circuit boards, and those having heat producing elements all require superior heat dissipation to maintain their normal operation. Conventionally, heat-sinking fins are installed on these heat producing elements to help heat dissipation. The heat-sinking fins and the heat producing elements are jointly referred to as “objects to be heat-dissipated.” Some may even have fans for additional ventilation. However, heat-sinking fins, as no power consumption is involved, are still the most popular means.


As the heat producing elements are getting more powerful, more heat is produced and the heat-sinking fins have to be bigger for increased surface area, making the product larger and heavier and contradicting the downsizing trend of electronic products.


Additionally, as some of the heat producing elements are for outdoor usage and are exposed directly to sun light and rain, and some are installed around salt marshes and hot spring and have to withstand the harsh environment. Therefore, for aluminum-made heat-sinking fins, they have to be further treated by anodizing anti-oxidation processing. However, anodizing treatment is not environment friendly, causing high production and waste processing cost.


SUMMARY OF THE INVENTION

The invention provides a composite for coating and sputtering a heat-dissipating film. The composite contains silicon carbide of 25˜30 wt. % (weight percentage), teflon-based resin of 9-11 wt. %, and diluted ketones/alcohols-group material of 60˜65 wt. %. These components are mixed and blended to be capable of being coated, sputtered, and cured on the surface of an object to be heat-dissipated. According to experiment result, if sputtered on iron, the composite is able to achieve heat dissipation 20˜30 times better than baking varnish. In addition, the composite could be directly applied to aluminum and is able to achieve heat dissipation 10˜15 times better than aluminum of anodizing treatment. As such, there is no need to adopt heat-sinking fins of large surface area. The product therefore could be effectively downsized, conforming to the compactness trend of current product design. This is a major objective of the present invention.


Furthermore, the composite, after being sputtered and coated on the object to be heat-dissipated, is able to provide resistance to erosion and harsh weather. The conventional anodizing treatment therefore could be omitted and the production and recycling cost is significantly reduced. This is another objective of the present invention.


Additionally, to recycle a product coated with a heat-dissipating film made of the composite, there is no need to scrape and scrub the heat-dissipating film. When the product is burned in a furnace, due to the composite has different specific weight and material characteristics, the composite would be automatically separated and recovered. This is yet another objective of the present invention.


More importantly, the composite could be sputtered and coated on the surface of various metals (such as Fe, Al, Cu), various non-metallic materials (such as PP, PC, ABS), soft ceramic, various soft petroleum-based materials (such as acrylic, silicon), pure graphite, etc. In other words, the composite is widely applicable and, regardless the applied surface's shape and condition, the heat-dissipating performance could be easily enhanced. This is still another objective of the present invention.


The foregoing objectives and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.


Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is a schematic diagram showing the components of a composite for a heat-dissipating film according to the present invention.



FIG. 2 is a flow-chart diagram showing the process of manufacturing the composite of FIG. 1.



FIG. 3 is a flow-chart diagram showing the application of the composite of FIG. 1 on an object to be heat-dissipated.





DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following descriptions are exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims.



FIG. 1 is a schematic diagram showing the composition of a heat-dissipating film according to the present invention. As illustrated, the heat-dissipating film is made of a composite containing silicon carbide of 25˜30 wt. % (weight percentage), teflon-based resin of 9-11 wt. %, and diluted ketones/alcohols-group material of 60˜65 wt. %. The foregoing composition is obtained from repeated experiments and the composite thus formed could be coated and cured on the surface of an object to be heat-dissipated into a heat-dissipating film for enhanced heat dissipation performance. With such a heat-dissipating film, there is no need to rely on heat-sinking fins of large surface area. Therefore, production cost is reduced, recycling is easier, and highly contaminating anodizing treatment is avoided without sacrificing the robustness against erosion and harsh weather. The experiments are summarized in the following table:

















Major







component
Percentage
Additives
Percentage
Outcome
Accepted







aluminum
70
PU resin
10
The major
No


nitride

methanol
20
component






deposits; caking is






produced; the






composite is






sticky, cannot be






stirred, and is not






usable.


aluminum
30
PU resin
20
The phenomenon
No


nitride

toluene
50
of caking,






stickiness,






deposition is






worse and






the composite has






unacceptable






odor.


aluminum
30
PU resin
10
Deposition still
No


nitride

acetone
60
presents but the






composite could






be sputtered;






however, there is






too much wasted






major component and






no practical






value.


aluminum
40
PU resin
10
Deposition and
No


nitride

methyl
50
caking are




ethyl

improved but the




ketone

composite still






cannot be






bucketed and






sputtered and, if






stored under room






temperature, has






the danger of






evaporation.


aluminum
50
PP
10
Components are
No


nitride

methanol
40
not blended






together and the






composite is not






usable.


aluminum
50
PP
10
Components are
No


nitride

acetone
40
not blended






together and the






composite is not






usable.


aluminum
40
PP
10
Components are
No


nitride

methyl
50
not blended




ethyl

together and the




ketone

composite is not






usable.


aluminum
50
acrylicresin
10
Components are
No


nitride

methanol
40
not blended






together and the






composite is not






usable.


aluminum
60
acrylic
10
The composite is
No


nitride

acetone
30
sticky, has caking






and low fluidness,






and cannot be






sputtered.


aluminum
50
acrylic
10
The composite is
No


nitride

methyl
30
sticky, has caking




ethyl

and low fluidness,




ketone

and cannot be






sputtered.


aluminum
60
silicon
10
Components are
No


nitride

methanol
40
not blended






together and the






composite is not






usable.


aluminum
70
silicon
10
Components are
No


nitride

acetone
20
not blended






together and the






composite is not






usable.


aluminum
40
silicon
10
Components are
No


nitride

methyl
50
not blended




ethyl

together and the




ketone

composite is not






usable.


aluminum
50
epoxy
10
Components are
No


nitride

methanol
40
not blended






together and the






composite is not






usable.


aluminum
60
epoxy
10
Components are
No


nitride

acetone
30
not blended






together and the






composite is not






usable.


aluminum
60
epoxy
10
Components are
No


nitride

methyl
30
not blended




ethyl

together and the




ketone

composite is not






usable.


aluminum
60
teflon
10
Components are
No


nitride

methanol
20
not blended






together and the






composite is not






usable.


aluminum
60
teflon
10
Components are
No


nitride

toluene
30
not blended






together and the






composite is not






usable.


aluminum
70
teflon
10
Deposition still
No


nitride

acetone
20
presents but the






composite could






be sputtered;






however, there is






too much wasted






major component






and no practical






value.


aluminum
50
teflon
10
Deposition still
No


nitride

methyl
40
presents but the




ethyl

composite could




ketone

be sputtered;






however, there is






too much wasted






major component






and no practical






value.


boron
70
PU
10
The major
No


nitride

methanol
20
component






deposits; caking is






produced; the






composite is






sticky, cannot be






stirred, and is not






usable.


boron
60
PU
10
The major
No


nitride

toluene
30
component






deposits; caking is






produced; the






composite is






sticky, cannot be






stirred, and is not






usable.


boron
50
PU
10
The major
No


nitride

acetone
40
component's






deposition is






improved but the






composite still






cannot be






bucketed and






sputtered.


boron
50
PU
10
The phenomenon
No


nitride

methyl
40
of the major




ethyl

component's




ketone

deposition,






stickiness, caking,






and unable-to-stir






is improved but






the composite still






cannot be






bucketed and






sputtered.


boron
60
PU
10
Components are
No


nitride

methanol
30
not blended






together and the






composite is not






usable.


boron
60
PP
10
The major
No


nitride

toluene
30
component






deposits; caking is






produced; the






composite is






sticky, cannot be






stirred, and is not






usable.


boron
50
PP
10
Deposition still
No


nitride

acetone
40
presents but the






composite could






be sputtered;






however, there is






too much wasted






major component






and no practical






value.


boron
50
acrylic
10
Components are
No


nitride

methanol
40
not blended






together and the






composite is not






usable.


boron
50
acrylic
10
The composite is
No


nitride

toluene
20
sticky, has caking






and low fluidness,






and cannot be






sputtered.


boron
70
acrylic
10
The composite is
No


nitride

acetone
20
sticky, has caking






and low fluidness,






and cannot be






sputtered.


boron
40
acrylic
10
Caking is still
No


nitride

methyl
50
present but




ethyl

fluidness is




ketone

improved; and,






even the






composite is






usable, it cannot






be mass-produced.


boron
30
silicon
10
Components are
No


nitride

methanol
60
not blended






together and the






composite is not






usable.


boron
40
silicon
10
Components are
No


nitride

acetone
50
not blended






together and the






composite is not






usable.


boron
30
silicon
10
The phenomenon
No


nitride

toluene
60
of caking,






stickiness, sinking






is worse and the






composite has






unacceptable






odor.


boron
30
silicon
10
Caking is still
No


nitride

methyl
60
present but




ethyl

fluidness is




ketone

improved; and,






even the






composite is






usable, it cannot






be mass-produced.


boron
70
epoxy
10
Components are
No


nitride

methanol
20
not blended






together and the






composite is not






usable.


boron
70
epoxy
10
The phenomenon
No


nitride

toluene
20
of caking,






stickiness, sinking






is worse and the






composite has






unacceptable






odor.


boron
40
epoxy
10
Deposition still
No


nitride

acetone
50
presents but the






composite could






be sputtered;






however, there is






too much wasted






major component






and no practical






value.


boron
20
epoxy
10
Deposition still
No


nitride

methyl
70
presents but the




ethyl

composite could




ketone

be sputtered;






however, there is






too much wasted






major component






and no practical






value.


boron
70
teflon
10
Components are
No


nitride

methanol
20
not blended






together and the






composite is not






usable.


boron
40
teflon
10
The major
No


nitride

toluene
50
component






deposits; caking is






produced; the






composite is






sticky, cannot be






stirred, and is not






usable.


boron
20
teflon
10
Deposition still
No


nitride

acetone
70
presents but the






composite could






be sputtered;






however, there is






too much wasted






major component






and no practical






value.


boron
40
teflon
10
The major
No


nitride

methyl
50
component




ethyl

deposits; caking is




ketone

produced, the






composite is






sticky, cannot be






stirred, and is not






usable.


silicon
20
PU
10
The composite is
No


carbide

methanol
70
better than the






previous one but






still cannot be






bucketed and






sputtered and, if






stored under room






temperature, has






the danger of






evaporation.


silicon
10
PU
10
Deposition still
No


carbide

acetone
80
presents but the






composite could






be sputtered;






however, there is






too much wasted






major component






and no practical






value.


silicon
10
PP
10
The major
No


carbide

methanol
80
component






deposits; caking is






produced; the






composite is






sticky, cannot be






stirred, and is not






usable.


silicon
10
PP
10
The phenomenon
No


carbide

toluene
80
of caking,






stickiness, sinking






is worse and the






composite has






unacceptable






odor.


silicon
30
acrylic
10
The composite is
No


carbide

methanol
60
better than the






previous one but






still cannot be






bucketed and






sputtered and, if






stored under room






temperature, has






the danger of






evaporation.


silicon
50
silicon
10
The components
No


carbide

toluene
40
are effectively






blended but






deposition is






obvious; and the






composite has to






be further worked






by continuous






shaking,






increasing the






production






difficulty


silicon
50
silicon
10
The components
No


carbide

acetone
40
begin to dissolve






but there is highly






sticky caking






whose






concentration is






too high to






decompose.


silicon
10
epoxy
10
The major
No


carbide

methanol
80
component






deposits; caking is






produced; the






composite is






sticky, cannot be






stirred, has bad






odor, and is not






usable.


silicon
30
epoxy
10
Caking is still
Close to


carbide

methyl
60
present but
be




ethyl

fluidness is
accepted




ketone

improved; and,






even the






composite is






usable, it cannot






be






mass-produced;






the composite has






bad odor and






probably cannot






pass examination;






however, the






composite could






be actually






applied by






sputtering despite






a weak adhesion






and more






suspended






matters.










From the last experiment, the following conclusion could be drawn:
    • 1. Silicon carbide has the highest feasibility as the major component.
    • 2. Compared to other experimented major components, there are more and stable sources and suppliers for silicon carbide, and therefore the composite's cost is more controllable.
    • 3. To enhance the decomposition of suspended matters and adhesion strength of sputtering, more extensive analysis has to be conducted so as to increase the stability of the composite's manufacturing.
    • 4. The most important issue is how well silicon carbide is integrated with high-level resin and whether heat conductivity could be continuously maintained after sputtering.
    • 5. Additional components are required to achieve uniform coating without causing accumulated spots.
    • 6. Numerous dissolvents for chemical combination are available and those that are hazardous could be avoided for enhanced safety.
    • 7. The major component is easy to obtain and there is no concern over shortage or monopoly.


      Accordingly, additional experiments are conducted and summarized in the following table:

















Major







com-
Percent-

Percent-


ponent
age
Additives
age
Outcome
Accepted







silicon
30
teflon
9-11
There are
OK


carbide

acetone
60
extraneous






suspended matters






but, if well






shaken, the






composite's






adhesion is not






affected; the






composite






evaporates faster






but has feasible






adhesion; the






composite seems






satisfactory yet






the adhesion is not






uniform as spots






are present.


silicon
30
teflon
9-11
There are
OK


carbide

acetone
60
extraneous






suspended matters






but, if well






shaken, the






composite's






adhesion is not






affected; the






composite






evaporates faster






but has feasible






adhesion; the






composite seems






satisfactory yet






the adhesion is not






uniform as spots






are present; and,






up to now, it






seems that spots






are standard






phenomenon.


silicon
30
teflon
9-11
There are
OK


carbide

methyl
60
extraneous




ethyl

suspended matters




ketone

but, if well






shaken, the






composite's






adhesion is not






affected; the






composite






evaporates faster






but has feasible






adhesion; the






composite seems






satisfactory yet






the adhesion is not






uniform as spots






are present.


silicon
30
teflon
9-11
There are
OK


carbide

methyl
60
extraneous




ethyl

suspended matters




ketone

but, if well






shaken, the






composite's






adhesion is not






affected; the






composite






evaporates faster






but has feasible






adhesion; the






composite seems






satisfactory yet






the adhesion is not






uniform as spots






are present; and,






up to now, it






seems that spots






are standard






phenomenon.


silicon
30
teflon
9-11
There are
OK


carbide

acetone
30
extraneous




methyl
30
suspended matters




ethyl

but, if well




ketone

shaken, the






composite's






adhesion is not






affected; the






composite






evaporates faster






but has feasible






adhesion; the






composite seems






satisfactory yet






the adhesion is not






uniform as spots






are present; and,






up to now, it






seems that spots






are standard






phenomenon;






ionizing state is






more obvious and






distribution is






more uniform






with no






deposition; using






a single dissolvent






would have even






better effect with






enhanced






volatility;






however, lack of






film thickness is






still an issue.


silicon
30
teflon
9-11
There are
OK


carbide

acetone
25
extraneous




methyl
30
suspended matters




ethyl
10
but, if well




ketone

shaken, the




methanol

composite's






adhesion is not






affected; the






composite






evaporates faster






but has feasible






adhesion; the






composite seems






satisfactory yet






the adhesion is not






uniform as spots






are present; and,






up to now, it






seems that spots






are standard






phenomenon;






ionizing state is






more obvious and






distribution is






more uniform






with no






deposition; using






a single dissolvent






would have even






better effect with






enhanced






volatility;






however, lack of






film thickness is






still an issue; the






ionizing state is






even more evident






after adding






methanol; the






uniformity of






particle sputtering






is improved with






even better






volatility; gaps






between particles






and film thickness






are stable; there is






no non-uniformity






problem;






however, the






volatility of






methanol could be






dangerous.


silicon
30
teflon
9-11
There are


carbide

acetone
25
extraneous




methyl
30
suspended matters




ethyl
10
but, if well




ketone

shaken, the




ethanol

composite's






adhesion is not






affected; the






composite






evaporates faster






but has feasible






adhesion; the






composite seems






satisfactory yet






the adhesion is not






uniform as spots






are present; and,






up to now, it






seems that spots






are standard






phenomenon;






ionizing state is






more obvious and






distribution is






more uniform






with no






deposition; using






a single dissolvent






would have even






better effect with






enhanced






volatility;






however, lack of






film thickness is






still an issue; the






ionizing state is






even more evident






after adding






methanol; the






uniformity of






particle sputtering






is improved with






even better






volatility; gaps






between particles






and film thickness






are stable; there is






no non-uniformity






problem;






however, the






volatility of






methanol could be






dangerous;






however, there is






no volatile gas






that would be






hazardous to






human.


silicon
25
teflon
9-11
For repeated
OK


carbide

acetone
25
applications for




methyl
30
20 times, the




ethyl
10
result is stable and




ketone

there is no




ethanol

non-uniform






sputtering.










Up to now, the composition of the composite is determined.


From the above experiments, the ketones/alcohols-group material 3 could be a composite of acetone, methyl ethyl ketone, methanol, and ethanol of appropriate amounts. The composite is then added and blended into the silicon carbide 1 to obtain a coating composite for sputtering onto an object to be heat-dissipated for enhanced heat dissipation. Up to the present time, coating with 0.02 um˜0.05 um has been successfully developed. To satisfy the requirement for a specific color, after repeated experiments, the present inventor found that gemstone powders could be optionally added and, by the interaction between the gemstone powders and the major component, the composite of a specific color could be achieved. In other words, the added gemstone powders are mainly used for mixing and fixing colors without sacrificing the heat conductivity. Therefore, depending on the color requirement, gemstone powders of appropriate amount could be added. The percentage of the gemstone powders could affect the shading of the color.


The manufacturing of the composite of the present invention could be conducted according to FIG. 2. As illustrated, after the silicon carbide is obtained, it first undergoes spheroidization and grinding/granulation, and dispensing. Then it is combined and mixed with a fixed amount of additives (teflon resin, gemstone powders). It is then blended with a fixed amount of dissolvent (acetone, methyl ethyl ketone, ethanol). Finally, it is dispensed for future application.


The composite's coating operation is depicted in FIG. 3. As illustrated, the composite is precisely sputtered and coated on the object to be heat-dissipated, and then cured to form a heat dissipation film. There are various types of curing, such as drying under room temperature, low- and mid-temperature sintering. The chose of curing method depends on the required film thickness and color. As the film thickness and color are also determined by the percentages of the major component and gemstone powders. These factors have to be jointly considered to determine the way of application of the composite. The working time would also vary accordingly and there is no fixed application procedure.


According to the foregoing description, the composite of the present invention, according to detailed experiments, is capable of being directly coated and sputtered on the surface of the object to be heat-dissipated, and then cured to a film of pre-determined thickness. As such, the heat-dissipating performance could be conveniently enhanced. There is no need to rely on heat-sinking fins of large surface area. The production cost is reduced, recycling is easier, and the highly contaminating anodizing treatment could be avoided, while the robustness against erosion and harsh weather is still maintained.


While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.

Claims
  • 1. A composite comprising: a silicon carbide of 25˜30 wt. %;a teflon-based resin of 9-11 wt. %; anda diluted ketones-group material of 60˜65 wt. %;combined and blended into a material capable of being sputtered, coated, and cured into a heat-dissipating film of a pre-determined thickness on an object to be heat-dissipate.
  • 2. The composite according to claim 1, wherein said silicon carbide is of 30 wt. %; and said ketones-group material is acetone of 60 wt. %.
  • 3. The composite according to claim 1, wherein said silicon carbide is of 30 wt. %; and said ketones-group material is methyl ethyl ketone of 60 wt. %.
  • 4. The composite according to claim 1, wherein said silicon carbide is of 30 wt. %; and said ketones-group material contains acetone of 30 wt. % and methyl ethyl ketone of 30 wt. %.
  • 5. The composite according to claim 1, wherein said teflon-based resin contains gemstone powders to achieve a specific color.
  • 6. A composite comprising: a silicon carbide of 25˜30 wt. %;a teflon-based resin of 10 wt. %; anda diluted ketones/alcohols-group material of 60˜65 wt. %;combined and blended into a material capable of being sputtered, coated, and cured into a heat-dissipating film of a predetermined thickness on an object to be heat-dissipate.
  • 7. The composite according to claim 6, wherein said silicon carbide is of 25 wt. %; and said ketones/alcohols-group material contains acetone of 25 wt. %, methyl ethyl ketone of 30 wt. %, and methanol of 10 wt. %.
  • 8. The composite according to claim 6, wherein said silicon carbide is of 25 wt. %; and said ketones/alcohols-group material contains acetone of 25 wt. %, methyl ethyl ketone of 30 wt. %, and ethanol of 10 wt. %.
  • 9. The composite according to claim 6, wherein said teflon-based resin contains gemstone powders to achieve a specific color.