U.S. patent application number 10/164098 was filed with the patent office on 2002-12-26 for protective sealable transparent flexible membrane for electronic touch screens.
Invention is credited to Cleereman, Robert J., Flavin, Frank J., Hoagland, Mary M., Hus, Michael E., Langmaid, Joseph A., Peterson, Curt E., Wenzel, Jeffrey D..
Application Number | 20020195910 10/164098 |
Document ID | / |
Family ID | 23158438 |
Filed Date | 2002-12-26 |
United States Patent
Application |
20020195910 |
Kind Code |
A1 |
Hus, Michael E. ; et
al. |
December 26, 2002 |
Protective sealable transparent flexible membrane for electronic
touch screens
Abstract
A protective sealable transparent membrane comprised of a film
and a frame which is suspended above a touch screen of a personal
electronic device encased in a protective enclosure. The protective
sealable transparent membrane allows activation of the touch
screen, scratch resistance and a water and dust tight seal.
Inventors: |
Hus, Michael E.; (Midland,
MI) ; Wenzel, Jeffrey D.; (Saginaw, MI) ;
Cleereman, Robert J.; (Midland, MI) ; Langmaid,
Joseph A.; (Caro, MI) ; Peterson, Curt E.;
(Midland, MI) ; Flavin, Frank J.; (Midland,
MI) ; Hoagland, Mary M.; (Midland, MI) |
Correspondence
Address: |
THE DOW CHEMICAL COMPANY
INTELLECTUAL PROPERTY SECTION
P. O. BOX 1967
MIDLAND
MI
48641-1967
US
|
Family ID: |
23158438 |
Appl. No.: |
10/164098 |
Filed: |
June 4, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60300280 |
Jun 22, 2001 |
|
|
|
Current U.S.
Class: |
312/223.2 |
Current CPC
Class: |
G06F 2200/1633 20130101;
H04M 2250/22 20130101; G06F 1/1626 20130101; H04M 1/18
20130101 |
Class at
Publication: |
312/223.2 |
International
Class: |
A47B 097/00 |
Claims
What is claimed is:
1. A protective sealable transparent flexible membrane comprising a
film and a frame, which fits into a protective enclosure for a
personal electronic device wherein said membrane is suspended above
the personal electronic device allowing activation of the personal
electronic device and provides a liquid and particulate tight
seal.
2. The protective sealable transparent flexible membrane of claim 1
wherein the film comprises a transparent thermoplastic
elastomer.
3. The protective sealable transparent flexible membrane of claim 2
wherein the film comprises a transparent thermoplastic
polyurethane.
4. The protective sealable transparent flexible membrane of claim 1
wherein the frame comprises a thermoplastic elastomer.
5. The protective sealable transparent flexible membrane of claim 4
wherein the frame comprises a thermoplastic polyurethane.
6. The protective sealable transparent flexible membrane of claim 4
wherein the frame has a hardness between about Shore 50 A to about
Shore 65 D.
7. The protective sealable transparent flexible membrane of claim 1
further comprising molded-in buttons.
8. The protective sealable transparent flexible membrane of claim 1
further comprising decorative printing.
Description
CROSS REFERENCE STATEMENT
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/300,280, filed Jun. 22, 2001.
FIELD OF THE INVENTION
[0002] The present invention relates to a protective sealable
transparent membrane which covers the touch screen of a personal
electronic device encased in a protective enclosure.
BACKGROUND OF THE INVENTION
[0003] Personal electronic devices, such as hand held computers,
cell phones, pagers, personal digital assistants (PDAs), gaming
devices, electronic music players, voice recorders, global
positioning systems (GPS) and the like, have become common place in
today's society. These personal electronic devices have found
utility in all aspects of life including personal and/or
professional activities. A touch screen is commonly used to input
and view data into personal electronic devices. The advantage of a
touch screen is that the operator may simply touch the display
object or portion of the screen to highlight or select or otherwise
input information.
[0004] In most environments, and in outdoor environments in
particular, personal electronic devices are subject to liquids,
dust, foods, grease, moisture and other contaminants. Contamination
of the touch screen can adversely affect the operability of the
personal electronic device. Following contamination, these devices
need to be cleaned, further exposing the personal electronic
devices to harsh cleaning fluids, liquids and solutions. Thus, in
order to operate properly in harsh environments, an enclosure with
a protective transparent membrane having a liquid tight seal is
needed to protect sensitive electronic display elements.
[0005] Prior art techniques have attempted to solve this problem in
several ways. Typically, an enclosure with a front cover for a
touch screen contains one or more gaskets. Not only do gaskets leak
with time and exposure to environmental contamination and cleaning
fluids, but they also require the use of additional assembly steps
and addition of the gasket(s) itself. The gasket must be attached
and seated properly in order to function effectively. The use of
gaskets requires multiple operations and parts which makes front
covers using gaskets expensive to manufacture. Gaskets also tend to
leak after a relatively short period of time due to the expansion
and contraction of the gasket itself due to temperature changes in
the environment.
[0006] Other attempts to solve the problem involve an enclosure
with an openable/closeable protective lid. These solutions are less
than desirable as they are not sealed to liquids and must be opened
to activate the touch screen, thus providing opportunities for
exposing the touch screen to potential contamination. One such
example is taught in U.S. Pat. No. 5,990,874 of a personal
electronic device with an attachable openable/closeable lid where
there is limited capability to activate the touch screen by
depressing the protective lid while closed. Unfortunately, the lid
does not provide a seal to liquids and the elements and the only
function through the lid is the ability to turn the personal
electronic device on or off.
[0007] Accordingly a need exists for a protective sealable
transparent flexible membrane for personal electronic devices
having touch screens encased in a protective enclosure, which
allows activation of the touch screen through the membrane,
provides an effective liquid and dust tight seal and protects the
touch screen from the environment and elements. Further, it is
desirable that the number of parts, assembly steps and hence the
cost can be reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view showing the protective
transparent flexible membrane.
[0009] FIG. 2 is a perspective view of the protective transparent
flexible membrane and underside of the top portion of the
protective enclosure for a personal electronic device that the
protective transparent flexible membrane fits into.
[0010] FIG. 3 is an exploded perspective view of the protective
transparent flexible membrane, top portion of the protective
enclosure, a personal electronic device and the mating bottom
portion of the protective enclosure.
SUMMARY OF THE INVENTION
[0011] It is an objective of the invention to provide a protective
sealable transparent flexible membrane that fits into a protective
enclosure for a personal electronic device through which the touch
screen can be viewed.
[0012] It is another objective of the invention to provide a
protective sealable transparent flexible membrane that when in
place in the protective enclosure provides protection and scratch
resistance for the touch screen of the personal electronic
device.
[0013] It is another objective of the invention to provide a
protective sealable transparent flexible membrane that when in
place in the protective enclosure provides a liquid, especially
water, tight seal.
[0014] It is another objective of the invention to provide a
protective sealable transparent flexible membrane that when in
place in the protective enclosure provides a particulate,
especially dust, tight seal.
[0015] It is yet another objective of the invention to provide a
protective sealable transparent flexible membrane that when in
place in the protective enclosure allows for activation of the
touch screen on the personal electronic device through the
membrane.
[0016] It is still a further objective of the invention to provide
a protective sealable transparent flexible membrane that is easy to
replace.
[0017] It is still a further objective of the invention to provide
a protective sealable transparent flexible membrane that is easy to
manufacture.
[0018] An embodiment of the present invention is a protective
sealable transparent flexible membrane comprising a film and a
frame, which fits into a protective enclosure and is suspended
above a personal electronic device, said protective sealable
transparent flexible membrane provides a liquid and particulate
tight seal.
[0019] In a further embodiment of the present invention, the film
is a flexible transparent thermoplastic, preferably a transparent
thermoplastic polyurethane elastomer.
[0020] In a further embodiment of the present invention, the frame
is a flexible thermoplastic elastomer, preferably a thermoplastic
polyurethane elastomer.
[0021] In a further embodiment of the present invention, the film
and frame are the same or different flexible thermoplastic
elastomer, preferably the same or different thermoplastic
polyurethane elastomer.
[0022] In a further embodiment of the invention the film is a
flexible thermoplastic, preferably a thermoplastic urethane
elastomer, with a hardness of between about Shore 50 A to about
Shore 65 D.
[0023] In yet a further embodiment of the present invention, the
protective sealable transparent flexible membrane comprises
buttons, preferably molded-in buttons.
[0024] In yet a further embodiment of the invention, the protective
sealable transparent flexible membrane comprises decorative
printing.
DETAILED DESCRIPTION OF THE INVENTION
[0025] The present invention is a protective sealable transparent
flexible membrane. Said protective sealable transparent flexible
membrane fits into a protective enclosure which houses a personal
electronic device having a display and/or touch screen, such as a
hand held computer, cell phone, a pager, a personal digital
assistant (PDA), a gaming device, an electronic music player, a
voice recorder, a global positioning system (GPS) and the like. The
protective sealable transparent flexible membrane 1 shown in FIG. 1
having a top side and an underside and comprising a film 11 and a
frame 12. As shown in FIG. 2, the protective sealable transparent
flexible membrane 1 fits into the underside of the top portion of a
protective enclosure 21 having an under side 22 and a top side 23.
The protective sealable transparent flexible membrane 1 can fit
into the topside or underside of the top portion of the protective
enclosure 21. The frame 12 forms a mechanical seal with a mating
recess 24 in the top portion of the protective enclosure 21. The
top portion of the protective enclosure 21 mates with a bottom
portion of the protective enclosure 31 as shown in FIG. 3 to form
the protective enclosure for a personal electronic device 43.
[0026] The film 11 can be made from any translucent or preferably
transparent thermoplastic by any known film making process known in
the art. Preferably, the film is made from a translucent or
transparent polyamide, polyurethane (PU), polycarbonate (PC),
polyvinyl chloride (PVC), polyolefin (PO), such as polyethylene
(PE) and polypropylene (PP), polyacrylate, polyester, polysiloxane,
polystyrene (PS), styrene and acrylonitrile copolymer (SAN) or
mixtures thereof. Preferably the film is a thermoplastic
polyurethane (TPU). Preferably the film 11 is a thermoplastic
elastomer.
[0027] The film is must allow for activation of the touch screen
through it, for example by depressing the film. Preferably the film
is an elastomer. Moreover, the film has good flex fatigue
resistance so as to recover its original position after being
depressed when activating the touch screen, rigid enough to
maintain its position above the touch screen so as to minimize
unwanted screen activation, good hardness so as to afford scratch
resistance, good solvent resistance and good long term creep
properties so that it will not sag over time. Preferred hardness is
equal to or greater than Shore 50 A and equal to or less than Shore
65 D.
[0028] Preferably the film 11 has a thickness equal to or greater
than about 0.001 millimeter (mm), preferably equal to or greater
than about 0.01 mm, more preferably equal to or greater than about
0.02 mm and most preferably equal to or greater than about 0.04 mm.
Preferably the film 11 has a thickness equal to or less than about
0.5 mm, preferably equal to or less than about 0.1 mm, more
preferably equal to or less than about 0.08 mm, even more
preferably equal to or less than about 0.06 mm and most preferably
equal to or less than about 0.05 mm.
[0029] The frame 12 can be made from any thermoplastic elastomer
which can (1) be adhered to the film and (2) make a liquid and
particulate tight mechanical seal when fitted into the recess 24 in
the top portion of the protective enclosure 21. Suitable elastomers
are described, for example, in Billmeyer, F., Textbook of Polymer
Science, Interscience Publishers, New York, N.Y. (1965) and in
Kirk-Othmer Science of Chemical Technology 4.sup.th Ed, John Wiley
& Sons, New York N.Y. (1993). Preferably the frame is made from
a thermoplastic elastomer such as thermoplastic polyolefin (TPO),
polyethylene, such as low density polyethylene (LDPE), ethylene and
vinyl acetate copolymer (EVA), ethylene and propylene copolymers
(EP), polyvinyl chloride, polyurethane, polyamide, polyester and
mixtures thereof. Preferably the frame is made form a thermoplastic
polyurethane, such as PELLETHANE.TM. 2102-75A available from The
Dow Chemical Company.
[0030] The film 11 and the frame 12 may be made from different
thermoplastic elastomers or the same thermoplastic elastomer.
Preferably the film 11 and the frame 12 are made from thermoplastic
polyurethane.
[0031] The protective sealable transparent flexible membrane 1 is a
single part, but the film 11 and the frame 12 may be one or more
distinct parts. If the film 11 and frame 12 are a single part, it
must comprise a translucent or transparent thermoplastic elastomer.
If the film 11 and frame 12 are two or more parts, the frame can be
made by any known plastic processing technique, such as injection
molding, thermoforming, extrusion and die cutting, and the like.
The film 11 and the frame 12 may be attached to one another by any
means known in the art to form the protective sealable transparent
flexible membrane, for example by a mechanical bond or physically
with adhesives, solvent bonding, heat staking, sonic welding or
insert molding. A preferable method of bonding 11 to 12 is insert
molding, for example injection molding or thermoforming the frame
12 over the film 11 to form the protective sealable transparent
flexible membrane 1.
[0032] The protective sealable transparent flexible membrane can
vary in size, preferably it enables a view of the personal
electronic device within the protective enclosure and more
preferably a view of the touch screen of the personal electronic
device 43 housed within the protective enclosure.
EXAMPLE
[0033] The following example serves to demonstrate an embodiment of
the invention but is not intended to limit the scope of the
invention.
[0034] A thermoplastic polyurethane flexible film available as
PT9200 U type S-2332, natural/clear from Deerfield having a
thickness of 0.043 mm and a hardness in the range of Shore 50A to
Shore 65 D is used. The frame comprises PELLETHANE 2102-75A from
the Dow Chemical company. The protective sealable transparent
flexible membrane is formed by insert injection molding the frame
onto the film in an injection molding machine having a mold cavity
in the shape of the frame. A piece of the PT9200 U type S-2332
film, larger than the frame cavity, is placed between the mold
halves, the mold is closed and PELLETHANE 2102-75A is insert molded
onto the PT9200 U type S-2332 film. The PELLETHANE 2102-75A is
dried at a temperature between 80 to 95.degree. C. and the molding
conditions are a melt temperature between 200 to 215.degree. C.
with a mold temperature between 15 to 60.degree. C. The combined
frame and film are removed from the mold and excess film is die cut
away to provide a protective sealable transparent flexible membrane
of the desired shape.
[0035] The resulting protective sealable transparent flexible
membrane is placed into a top portion of a protective enclosure
such that the frame mates with a recess in the top portion of the
protective enclosure to form a water and dust tight seal. A
personal electronic device is placed in the protective enclosure
and the top portion of the protective enclosure is mated with the
bottom portion of the protective enclosure. The resulting
protective sealable transparent flexible membrane allows for
activation of the touch screen as well as good scratch resistance,
water and dust resistance.
* * * * *