U.S. patent application number 11/827696 was filed with the patent office on 2008-04-10 for encapsulation of electrically energized articles.
Invention is credited to Bryan Steven Bishop, Michael Eugene Donelson, John Walker Gilmer, Gary Wayne Hartley, James Collins Maine, Ryan Thomas Neill, Theodore Robert Trautman, Robert Erik Young.
Application Number | 20080085390 11/827696 |
Document ID | / |
Family ID | 38922789 |
Filed Date | 2008-04-10 |
United States Patent
Application |
20080085390 |
Kind Code |
A1 |
Neill; Ryan Thomas ; et
al. |
April 10, 2008 |
Encapsulation of electrically energized articles
Abstract
In one aspect the present invention relates to a method of
making an encapsulated electrically energized device, the method
comprising: providing a first layer and a second layer each
independently comprising a copolyester, providing the electrically
energized between the first and second layer, thermocompressively
fusing the first layer and the second layer to encapsulate the
electrically energized device by applying pressure at a temperature
sufficient to form the article, wherein the temperature at an
interface between the first and second layers is equal to or
greater than Tg of the first layer and the second layer, and
wherein the polyester layers have a flow during encapsulation less
than the flow that induces fractures in the electrically energized
device. In one aspect the present invention relates to a method of
making an encapsulated electrically energized device, the method
comprising: providing a first layer and a second layer each
independently comprising a copolyester, a polycarbonate, a
polyacrylate, polycarbonate/polyester miscible blends, or mixtures
thereof, providing the electrically energized between the first and
second layer, thermocompressively fusing the first layer and the
second layer to encapsulate the electrically energized device by
applying pressure at a temperature, sufficient to form the article,
to a perimeter of the surface of the first and second layers,
wherein the perimeter does not overlap the electrically energized
device, wherein the temperature at the interface of the first and
second layers is equal to or greater than Tg of the first layer and
the second layer, and wherein the polyester layers have a flow
during encapsulation less than the flow that induces fractures in
the electrically energized device.
Inventors: |
Neill; Ryan Thomas;
(Kingsport, TN) ; Hartley; Gary Wayne; (Kingsport,
TN) ; Donelson; Michael Eugene; (Gray, TN) ;
Trautman; Theodore Robert; (Avon, CT) ; Gilmer; John
Walker; (Kingsport, TN) ; Maine; James Collins;
(Church Hill, TN) ; Bishop; Bryan Steven;
(Kingsport, TN) ; Young; Robert Erik; (Kingsport,
TN) |
Correspondence
Address: |
Louis N. Moreno;Eastman Chemical Company
P.O.Box 511
Kingsport
TN
37662-5075
US
|
Family ID: |
38922789 |
Appl. No.: |
11/827696 |
Filed: |
July 13, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60849409 |
Oct 4, 2006 |
|
|
|
Current U.S.
Class: |
428/76 ; 427/66;
427/74; 427/96.6 |
Current CPC
Class: |
B29C 66/433 20130101;
B29C 66/72 20130101; B32B 7/05 20190101; C08L 69/00 20130101; Y10T
428/31797 20150401; B29C 66/739 20130101; B32B 37/06 20130101; Y10T
428/161 20150115; B32B 2457/206 20130101; B29C 66/7312 20130101;
Y10T 428/31928 20150401; B29C 66/7352 20130101; B32B 2457/202
20130101; B32B 37/0076 20130101; H01L 33/52 20130101; B29C 66/133
20130101; B29C 66/737 20130101; B29C 66/73921 20130101; B32B 27/365
20130101; B32B 2309/02 20130101; C08L 33/04 20130101; B29C 66/71
20130101; B32B 3/00 20130101; B32B 37/16 20130101; B32B 2309/04
20130101; Y10T 428/31786 20150401; B32B 37/0046 20130101; Y10T
428/31935 20150401; B32B 2457/08 20130101; G09F 13/22 20130101;
Y10T 428/31507 20150401; B32B 2367/00 20130101; B29C 65/02
20130101; Y10T 428/163 20150115; Y10T 428/239 20150115; B32B 27/08
20130101; B32B 2333/04 20130101; B32B 2457/00 20130101; H01L 31/049
20141201; B32B 37/185 20130101; B32B 2457/10 20130101; C08L 67/03
20130101; H01L 31/0481 20130101; B29C 66/43 20130101; B32B 2369/00
20130101; B29C 66/73117 20130101; B32B 37/182 20130101; B32B
2457/12 20130101; B29C 66/731 20130101; B32B 2309/12 20130101; Y10T
428/162 20150115; C08L 67/02 20130101; B32B 37/0007 20130101; B29C
66/7311 20130101; B32B 27/308 20130101; B32B 27/36 20130101; B32B
2457/20 20130101; H01L 2933/005 20130101 |
Class at
Publication: |
428/76 ; 427/66;
427/74; 427/96.6 |
International
Class: |
B32B 27/36 20060101
B32B027/36; B05D 5/00 20060101 B05D005/00 |
Claims
1. A method of making an encapsulated electrically energized
device, the method comprising: (a) providing a first layer and a
second layer each independently comprising a copolyester, (b)
providing the electrically energized device having a surface area
ranging from greater than 1 square foot (0.093 square meters) and
less than 120 square feet (11.2 square meters) between the first
and second layer (c) thermocompressively fusing the first layer and
the second layer to encapsulate the electrically energized device
by applying pressure ranging from 5 psig to 350 psig at a
temperature ranging from 180 F to 245 F for a period ranging from 5
minutes to 45 minutes to the surface of the first and second
layers, wherein the first and second layer each independently
ranges from 15 mil to 375 mil in thickness, wherein the temperature
at an interface of the first and second layers is equal to or
greater than Tg of the first layer and the second layer, and
wherein the first layer and the second layer increase in width
and/or length less than 5% relative to the initial width or length
of the first and second layer.
2. The method of claim 1, wherein the polyester has diol residues
comprising cycloaliphatic diols having 3 to 16 carbon atoms,
aliphatic diols having 3 to 12 carbon atoms and mixtures
thereof.
3. The method of claim 1, wherein the diol residues comprise
1,2-propanediol, 1,3-propanediol, neopentyl glycol,
2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol (trans-,
cis- or mixtures thereof), 1,4-cyclohexanedimethanol (trans-, cis-
or mixtures thereof), 1,3-cyclohexanedimethanol (trans-, cis- or
mixtures thereof), p-xylylene glycol and mixtures thereof.
4. The method of claim 1, wherein the polyester has an intrinsic
viscosity about 0.5 to about 1.2 dL/g measured by dissolving about
0.50 g of the polyester in about 100 mL of a solvent consisting of
60% by weight phenol and 40% by weight tetrachloroethane at 25
C.
5. The method of claim 1, wherein the polyester has an intrinsic
viscosity about 0.5 to about 1.0 dL/g measured by dissolving about
0.50 g of the polyester in about 100 mL of a solvent consisting of
60% by weight phenol and 40% by weight tetrachloroethane at 25
C.
6. The method of claim 1, wherein the polyester has an intrinsic
viscosity about 0.6 to about 0.9 dL/g measured by dissolving about
0.50 g of the polyester in about 100 mL of a solvent consisting of
60% by weight phenol and 40% by weight tetrachloroethane at 25
C.
7. The method of claim 1, wherein diacid residues of the polyester
comprise at least 80 mole percent of the diacid residues are
terephthalic acid residues.
8. The method of claim 1, wherein the less than 20 mole percent of
the diacid residues of the polyester are derived from phthalic
acid, isophthalic acid, 1,4-, 1,5-, 2,6- or
2,7-naphthalenedicarboxylic acid, 1,3- or
1,4-cyclohexanedicarboxylic acid (which may be cis, trans or a
mixture thereof), cyclohexanediacetic acid,
trans-4,4'-stilbenedicarboxylic acid, 4,4'-oxydibenzoic acid, 3,3'-
and 4,4'-bi-phenyldicarboxylic acids and aliphatic dicarboxylic
acids such as malonic, succinic, glutaric, adipic, pimelic,
suberic, azelaic, sebacic, nonane, decane, dodecanedicarboxylic
acids and mixtures thereof.
9. The method of claim 1, wherein the first layer and the second
layers are the same or different polymers.
10. The method of claim 1, wherein the electrically energized
devices comprises a light emitting capacitor (LEC), light emitting
diode (LED), printed "circuit board" that emit light when
energized, electrochromic layer, photovoltaic, transmitter,
receiver, antenna, electromagnet, electrode and smart sensor
capable of detecting wind speed and direction, temperature,
pressure, relative humidity, rainfall, motion, radiation, specific
chemical species or combinations thereof
11. The method of claim 1, wherein the electrically energized
device comprises an LEC.
12. An article comprising: a) a first layer and a second layer
comprising a polyester, polycarbonate, polyacrylate or
polycarbonate/polyester miscible blends; b) an electrically
energized device having a surface area ranging from greater than
about 1 square foot (0.93 square meters) and less than about 120
square feet (11.2 square meters) encapsulated between the first and
second layer; wherein the first and second layer are the same or
different, wherein the first and second layers each independently
have a thickness ranging from 15 mil to 375 mil, and wherein the
article remains moisture resistant after immersion in water at
25.degree. C. for 500 hours while continuously energized.
13. The article of claim 12, wherein the polyester has diol
residues comprising cycloaliphatic diols having 3 to 16 carbon
atoms, aliphatic diols having 3 to 12 carbon atoms and mixtures
thereof.
14. The article of claim 12, wherein the diol residues comprise
1,2-propanediol, 1,3-propanediol, neopentyl glycol,
2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol (trans-,
cis- or mixtures thereof), 1,4-cyclohexanedimethanol (trans-, cis-
or mixtures thereof), 1,3-cyclohexanedimethanol (trans-, cis- or
mixtures thereof), p-xylylene glycol and mixtures thereof.
15. The article of claim 12, wherein the polyester has an intrinsic
viscosity about 0.5 to about 1.2 dL/g measured by dissolving about
0.50 g of the polyester in about 100 mL of a solvent consisting of
60% by weight phenol and 40% by weight tetrachloroethane at 25
C.
16. The article of claim 12, wherein the polyester has an intrinsic
viscosity about 0.5 to about 1.0 dL/g measured by dissolving about
0.50 g of the polyester in about 100 mL of a solvent consisting of
60% by weight phenol and 40% by weight tetrachloroethane at 25
C.
17. The article of claim 12, wherein the polyester has an intrinsic
viscosity about 0.6 to about 0.9 dL/g measured by dissolving about
0.50 g of the polyester in about 100 mL of a solvent consisting of
60% by weight phenol and 40% by weight tetrachloroethane at 25
C.
18. The article of claim 12, wherein diacid residues of the
polyester comprise at least 80 mole percent of the diacid residues
are terephthalic acid residues.
19. The article of claim 12, wherein the less than 20 mole percent
of the diacid residues of the polyester are derived from phthalic
acid, isophthalic acid, 1,4-, 1,5-, 2,6- or
2,7-naphthalenedicarboxylic acid, 1,3- or
1,4-cyclohexanedicarboxylic acid (which may be cis, trans or a
mixture thereof), cyclohexanediacetic acid,
trans-4,4'-stilbenedicarboxylic acid, 4,4'-oxydibenzoic acid, 3,3'-
and 4,4'-bi-phenyldicarboxylic acids and aliphatic dicarboxylic
acids such as malonic, succinic, glutaric, adipic, pimelic,
suberic, azelaic, sebacic, nonane, decane, dodecanedicarboxylic
acids and mixtures thereof.
20. The article of claim 12, wherein the first layer and the second
layers are the same or different polymers.
21. The article of claim 12, wherein the electrically energized
devices comprises a light emitting capacitor (LEC), light emitting
diode (LED), printed "circuit board" that emit light when
energized, electrochromic layer, photovoltaic, transmitter,
receiver, antenna, electromagnet, electrode and smart sensor
capable of detecting wind speed and direction, temperature,
pressure, relative humidity, rainfall, motion, radiation, specific
chemical species or combinations thereof
22. The article of claim 12, wherein the electrically energized
device comprises an LEC.
23. A method of making an encapsulated electrically energized
device, the method comprising: (a) providing a first layer and a
second layer each independently comprising a copolyester, (b)
providing the electrically energized device having a surface area
ranging from greater than 1 square foot (0.93 square meters) and
less than 120 square feet (11.2 square meters) between the first
and second layer (c) thermocompressively fusing the first layer and
the second layer to encapsulate the electrically energized device
by applying pressure ranging from 5 psig to 350 psig at a
temperature ranging from 180 F to 245 F for a period ranging from 5
minutes to 45 minutes to the surface of the first and second
layers, wherein the first and second layer each independently
ranges from 15 mil to 375 mil in thickness, wherein the temperature
at an interface of the first and second layers is equal to or
greater than Tg of the first layer and the second layer, and
wherein the polyester layers have a flow during encapsulation less
than the flow that induces fractures in the electrically energized
device.
24. A method of making an encapsulated electrically energized
device, the method comprising: (a) providing a first layer and a
second layer each independently comprising a copolyester, (b)
providing the electrically energized device having a surface area
ranging from greater than 1 square foot (0.93 square meters) and
less than 120 square feet (11.2 square meters) between the first
and second layer (c) thermocompressively fusing the first layer and
the second layer to encapsulate the electrically energized device
by applying pressure ranging from 5 psig to 350 psig at a
temperature ranging from 180 F to 245 F for a period ranging from 5
minutes to 45 minutes to the surface of the first and second
layers, wherein the first and second layer each independently
ranges from 15 mil to 375 mil in thickness, wherein the temperature
at an interface of the first and second layers is equal to or
greater than Tg of the first layer and the second layer, and
wherein the polyester layers have a flow during encapsulation less
than the flow that induces burn-through in the electrically
energized device.
25. A method of making an encapsulated electrically energized
device, the method comprising: (a) providing a first layer and a
second layer each independently comprising a polyester, a
polycarbonate, a polyacrylate, or a polycarbonate/polyester
miscible blend, (b) providing the electrically energized device
having a surface area ranging from greater than 1 square foot (0.93
square meters) and less than 120 square feet (11.2 square meters)
between the first and second layer (c) thermocompressively fusing
the first layer and the second layer to encapsulate the
electrically energized device by applying pressure ranging from 5
psig to 750 psig at a temperature ranging from 180 F to 425 F for a
period ranging from 5 minutes to 45 minutes to a perimeter of the
surface of the first and second layers, wherein the perimeter does
not overlap the electrically energized device, wherein the first
and second layer each independently ranges from 15 mil to 375 mil
in thickness, wherein the temperature an interface of the first and
second layers is equal to or greater than Tg of the first layer and
the second layer, and wherein the first layer and the second layer
increase in width and/or length less than 5% relative to the
initial width or length of the first and second layer.
26. A method of making a laminated article comprising: (a)
providing a first layer and a second layer, each layer
independently comprising a copolyester layer, wherein at least one
layer further comprises a branching agent, (b) providing an
electrically energized device between the first and second layer,
and (c) applying pressure ranging from about 20 to about 400 psig
at a temperature ranging from about 20.degree. C. to about
80.degree. C. above the glass transition (Tg) of at least one layer
of the copolyester for a period of time ranging from about 0.5
minutes to about 120 minutes to form the laminated article, wherein
the temperature at an interface of the first layer and the second
layer is equal to or greater than the Tg of at least one of the
first layer and the second layer, and wherein the copolyester has
an inherent viscosity (IV) ranging from about 0.5 to about 1.2
dL/g, when measured at 25.degree. C. using 0.50 grams of polymer
per 100 mL of a solvent consisting of 60 weight percent phenol and
40 weight percent tetrachloroethane.
27. A laminated article comprising: (a) a first layer and a second
layer, each layer independently comprising a copolyester layer,
wherein at least one layer further comprises a branching agent, and
(b) an electrically energized device between the first and second
layer, wherein the copolyester has an inherent viscosity (IV)
ranging from about 0.5 to about 1.2 dL/g, when measured at
25.degree. C. using 0.50 grams of polymer per 100 mL of a solvent
consisting of 60 weight percent phenol and 40 weight percent
tetrachloroethane and wherein the article is prepared by applying
pressure ranging from about 20 to about 400 psig at a temperature
ranging from about 20.degree. C. to about 80.degree. C. above the
glass transition (Tg) of at least one layer of the copolyester for
a period of time ranging from about 0.5 minutes to about 120
minutes to form the laminated article, wherein the temperature at
an interface of the first layer and the second layer is equal to or
greater than the Tg of at least one of the first layer and the
second layer.
Description
RELATED APPLICATION DATA
[0001] This application claims benefit of provisional application
U.S. Ser. No. 60/849,409 filed 4 Oct. 2006, which is fully
incorporated by reference.
FIELD OF INVENTION
[0002] This invention relates to thermoplastic articles comprising
electrically energized materials and devices encapsulated between
polymer sheet and methods of making the articles. In particular,
this invention relates to methods of encapsulation of light
emitting materials and devices encapsulated, by lamination, between
polymer sheets comprising a polyester, a polycarbonate, a
polyacrylate, or a polycarbonate/polyester miscible blend and the
articles made therefrom.
BACKGROUND OF THE INVENTION
[0003] Various methods are known for encapsulation of decorative
and functional items between sheet made from polyesters,
polycarbonates, polyacrylates or polycarbonate/polyester miscible
blends. Electrically energized materials, including devices, have
been made by encapsulation with various polymers, but the devices
often have poor resistance to weathering, particularly
environmental moisture. Attempts of solve this problem have
included the use of adhesive layers for sheet lamination, which
also helps to prevent moisture penetration between layers and the
use of additional moisture-resistant polymer layers in addition to
the initial encapsulation layers. One problem with this approach is
that adhesives typically have low glass transition temperatures
(Tg) and the adhesive bonding of sheets often fails under
temperatures approaching the Tg of the adhesive. These solutions
increase the cost of the encapsulate devices. These problems are
magnified when the electrically energized materials or devices have
a large surface area, for example, greater than one square foot.
Furthermore, many of the known encapsulation techniques use
combinations of times, temperatures and pressures that degrade or
destroy the electrically energized devices, particularly when the
electrically energized devices have a large surface area.
[0004] A need exists for methods to encapsulate temperature and
pressure sensitive electrically energized materials and devices
with relatively thick protective polymeric layers, particularly
those devices having a large surface area.
BRIEF SUMMARY OF THE INVENTION
[0005] In one aspect the present invention relates to a method of
making an encapsulated electrically energized device, the method
comprising: [0006] (a) providing a first layer and a second layer
each independently comprising a copolyester, [0007] (b) providing
the electrically energized device having a surface area ranging
from greater than 1 square foot (0.093 square meters) and less than
120 square feet (11.2 square meters) between the first and second
layer [0008] (c) thermocompressively fusing the first layer and the
second layer to encapsulate the electrically energized device by
applying pressure ranging from 5 psig to 350 psig at a temperature
ranging from 180 F to 245 F for a period ranging from 5 minutes to
45 minutes to the surface of the first and second layers, [0009]
wherein the first and second layer each independently ranges from
15 mil to 375 mil in thickness, [0010] wherein the temperature at
an interface of the first and second layers is equal to or greater
than Tg of the first layer and the second layer, and [0011] wherein
the first layer and the second layer increase in width and/or
length less than 5% relative to the initial width or length of the
first and second layer.
[0012] In another aspect the present invention relates to a method
of making an encapsulated electrically energized device, the method
comprising: [0013] (a) providing a first layer and a second layer
each independently comprising a copolyester, [0014] (b) providing
the electrically energized device having a surface area ranging
from greater than 1 square foot (0.93 square meters) and less than
120 square feet (11.2 square meters) between the first and second
layer [0015] (c) thermocompressively fusing the first layer and the
second layer to encapsulate the electrically energized device by
applying pressure ranging from 5 psig to 350 psig at a temperature
ranging from 180 F to 245 F for a period ranging from 5 minutes to
45 minutes to the surface of the first and second layers, [0016]
wherein the first and second layer each independently ranges from
15 mil to 375 mil in thickness, [0017] wherein the temperature at
an interface of the first and second layers is equal to or greater
than Tg of the first layer and the second layer, and [0018] wherein
the polyester layers have a flow during encapsulation less than the
flow that induces fractures in the electrically energized
device.
[0019] In another aspect the present invention relates to a method
of making an encapsulated electrically energized device, the method
comprising: [0020] (a) providing a first layer and a second layer
each independently comprising a copolyester, [0021] (b) providing
the electrically energized device having a surface area ranging
from greater than 1 square foot (0.93 square meters) and less than
120 square feet (11.2 square meters) between the first and second
layer [0022] (c) thermocompressively fusing the first layer and the
second layer to encapsulate the electrically energized device by
applying pressure ranging from 5 psig to 350 psig at a temperature
ranging from 180 F to 245 F for a period ranging from 5 minutes to
45 minutes to the surface of the first and second layers, [0023]
wherein the first and second layer each independently ranges from
15 mil to 375 mil in thickness, [0024] wherein the temperature at
an interface of the first and second layers is equal to or greater
than Tg of the first layer and the second layer, and [0025] wherein
the polyester layers have a flow during encapsulation less than the
flow that induces burn-through in the electrically energized
device.
[0026] In another aspect the present invention relates to a method
of making an encapsulated electrically energized device, the method
comprising: [0027] (a) providing a first layer and a second layer
each independently comprising a polyester, a polycarbonate, a
polyacrylate, or a polycarbonate/polyester miscible blend, [0028]
(b) providing the electrically energized device having a surface
area ranging from greater than 1 square foot (0.93 square meters)
and less than 120 square feet (11.2 square meters) between the
first and second layer [0029] (c) thermocompressively fusing the
first layer and the second layer to encapsulate the electrically
energized device by applying pressure ranging from 5 psig to 750
psig at a temperature ranging from 180 F to 425 F for a period
ranging from 5 minutes to 45 minutes to a perimeter of the surface
of the first and second layers, wherein the perimeter does not
overlap the electrically energized device, [0030] wherein the first
and second layer each independently ranges from 15 mil to 375 mil
in thickness, [0031] wherein the temperature at an interface of the
first and second layers is equal to or greater than Tg of the first
layer and the second layer, and [0032] wherein the first layer and
the second layer increase in width and/or length less than 5%
relative to the initial width or length of the first and second
layer.
[0033] In another aspect the present invention relates to a method
of making an encapsulated electrically energized device, the method
comprising: [0034] (a) providing a first layer and a second layer
each independently comprising a copolyester, a polycarbonate, a
polyacrylate, polycarbonate/polyester miscible blends, or mixtures
thereof, [0035] (b) providing the electrically energized device
having a surface area ranging from greater than 1 square foot (0.93
square meters) and less than 120 square feet (11.2 square meters)
between the first and second layer [0036] (c) thermocompressively
fusing the first layer and the second layer to encapsulate the
electrically energized device by applying pressure ranging from 5
psig to 750 psig at a temperature ranging from 180 F to 425 F for a
period ranging from 5 minutes to 45 minutes to a perimeter of the
surface of the first and second layers, wherein the perimeter does
not overlap the electrically energized device, [0037] wherein the
first and second layer each independently ranges from 15 mil to 375
mil in thickness, [0038] wherein the temperature at an interface of
the first and second layers is equal to or greater than Tg of the
first layer and the second layer, and [0039] wherein the polyester
layers have a flow during encapsulation less than the flow that
induces fractures in the electrically energized device.
[0040] In another aspect the present invention relates to a method
of making an encapsulated electrically energized device, the method
comprising: [0041] (a) providing a first layer and a second layer
each independently comprising a copolyester, a polycarbonate, a
polyacrylate, polycarbonate/polyester miscible blends, or mixtures
thereof, [0042] (b) providing the electrically energized device,
having a surface area ranging from greater than 1 square foot (0.93
square meters) and less than 120 square feet (11.2 square meters),
between the first and second layer [0043] (c) thermocompressively
fusing the first layer and the second layer to encapsulate the
electrically energized device by applying pressure ranging from 5
psig to 750 psig at a temperature ranging from 180 F to 425 F for a
period ranging from 5 minutes to 45 minutes to a perimeter of the
surface of the first and second layers, wherein the perimeter does
not overlap the electrically energized device, [0044] wherein the
first and second layer each independently ranges from 15 mil to 375
mil in thickness, [0045] wherein the temperature at an interface of
the first and second layers is equal to or greater than Tg of the
first layer and the second layer, and [0046] wherein the polyester
layers have a flow during encapsulation less than the flow that
induces burn-through in the electrically energized device.
[0047] In other aspects the present invention relates to an article
comprising: [0048] a) a first layer and a second layer comprising a
polyester, a polycarbonate, a polyacrylate, or a
polycarbonate/polyester miscible blend; [0049] b) an electrically
energized device having a surface area ranging from greater than 1
square foot (0.93 square meters) and less than 120 square feet
(11.2 square meters) encapsulated between the first and second
layer; [0050] wherein the first and second layer are the same or
different, [0051] wherein the first and second layers each
independently have a thickness ranging from 15 mil to 375 mil, and
[0052] wherein the article remains moisture resistant after
immersion in water at 25.degree. C. for 500 hours while
continuously energized.
[0053] In another aspect the present invention relates to a method
of making an encapsulated electrically energized device, the method
comprising: [0054] (a) providing a first layer and a second layer
each independently comprising a polyester, a polycarbonate, a
polyacrylate, or a polycarbonate/polyester miscible blend, [0055]
(b) providing the electrically energized device having a surface
area ranging from greater than 1 square foot (0.93 square meters)
and less than 120 square feet (11.2 square meters) between the
first and second layer [0056] (c) thermocompressively fusing the
first layer and the second layer to encapsulate the electrically
energized device by applying pressure ranging from 5 psig to 750
psig at a temperature ranging from 180 F to 425 F for a period
ranging from 5 minutes to 45 minutes to a perimeter of the surface
of the first and second layers, wherein the perimeter does not
substantially overlap the electrically energized device, [0057]
wherein the first and second layer each independently ranges from
15 mil to 375 mil in thickness, [0058] wherein the temperature at
an interface of the first and second layers is equal to or greater
than Tg of the first layer and the second layer, and [0059] wherein
the first layer and the second layer increase in width and/or
length less than 5% relative to the initial width or length of the
first and second layer.
[0060] In another aspect the present invention relates to a method
of making an encapsulated electrically energized device, the method
comprising: [0061] (a) providing a first layer and a second layer
each independently comprising a copolyester, a polycarbonate, a
polyacrylate, polycarbonate/polyester miscible blends, or mixtures
thereof, [0062] (b) providing the electrically energized device
having a surface area ranging from greater than 1 square foot (0.93
square meters) and less than 120 square feet (11.2 square meters)
between the first and second layer [0063] (c) thermocompressively
fusing the first layer and the second layer to encapsulate the
electrically energized device by applying pressure ranging from 5
psig to 750 psig at a temperature ranging from 180 F to 425 F for a
period ranging from 5 minutes to 45 minutes to a perimeter of the
surface of the first and second layers, wherein the perimeter does
not substantially overlap the electrically energized device, [0064]
wherein the first and second layer each independently ranges from
15 mil to 375 mil in thickness, [0065] wherein the temperature at
an interface of the first and second layers is equal to or greater
than Tg of the first layer and the second layer, and [0066] wherein
the polyester layers have a flow during encapsulation less than the
flow that induces fractures in the electrically energized
device.
[0067] In another aspect the present invention relates to a method
of making an encapsulated electrically energized device, the method
comprising: [0068] (a) providing a first layer and a second layer
each independently comprising a copolyester, a polycarbonate, a
polyacrylate, polycarbonate/polyester miscible blends, or mixtures
thereof, [0069] (b) providing the electrically energized device,
having a surface area ranging from greater than 1 square foot (0.93
square meters) and less than 120 square feet (11.2 square meters),
between the first and second layer [0070] (c) thermocompressively
fusing the first layer and the second layer to encapsulate the
electrically energized device by applying pressure ranging from 5
psig to 750 psig at a temperature ranging from 180 F to 425 F for a
period ranging from 5 minutes to 45 minutes to a perimeter of the
surface of the first and second layers, wherein the perimeter does
not substantially overlap the electrically energized device, [0071]
wherein the first and second layer each independently ranges from
15 mil to 375 mil in thickness, [0072] wherein the temperature at
an interface of the first and second layers is equal to or greater
than Tg of the first layer and the second layer, and [0073] wherein
the polyester layers have a flow during encapsulation less than the
flow that induces burn-through in the electrically energized
device.
[0074] In another aspect the invention relates to an article
comprising: [0075] a) a first layer and a second layer comprising a
polyester, polycarbonate, polyacrylate or polycarbonate/polyester
miscible blends; [0076] b) an electrically energized device having
a surface area ranging from greater than about 1 square foot (0.93
square meters) and less than about 120 square feet (11.2 square
meters) encapsulated between the first and second layer; [0077]
wherein the first and second layer are the same or different,
[0078] wherein the first and second layers each independently have
a thickness ranging from 15 mil to 375 mil, and [0079] wherein the
article remains moisture resistant after immersion in water at
25.degree. C. for 500 hours while continuously energized.
[0080] In one aspect the processes of the present invention provide
articles that are moisture resistant after immersion in water at 25
C for 500 hours while continuously energized. "Immersion" refers to
the encapsulated electrically energized device, but not the
electrical connector or plug. In certain embodiments, the
electrical connector or plug may be partially embedded in the
laminate structure.
[0081] In another aspect the processes of the present invention
provide articles that function after ten cycles in an environmental
chamber cycling through a relative humidity ranging from 3% to 100%
during a 320 hour period.
[0082] In another aspect the processes of the present invention
provide articles that function after ten cycles in an environmental
chamber cycling through a temperature ranging from minus 20 F to
130 F during a 320 hour period.
[0083] In another aspect the processes of the present invention
provide articles that function after ten cycles in an environmental
chamber cycling through a relative humidity ranging from 3% to 100%
during a 320 hour period and that function after ten cycles in an
environmental chamber cycling through a temperature ranging from
minus 20 F to 130 F during a 320 hour period.
[0084] In one aspect the energized electrical devices have a
surface area ranging from 1 square foot to 120 square feet, or 5
square feet to 120 square feet, or square feet to 120 square feet,
or 25 square feet to 120 square feet, or 50 square feet to 120
square feet, or 75 square feet to 120 square feet or 100 square
feet to 150 square feet. In another aspect, the energized
electrical devices have a surface area ranging from 1 square foot
to 6 square feet, or 1 square foot to 12 square feet, or 1 square
foot to 32 square feet.
[0085] In one aspect the invention relates to methods of making a
laminated article comprising providing a first layer and a second
layer, each layer independently comprising a copolyester layer,
wherein at least one layer further comprises a branching agent,
providing an electrically energized device between the first and
second layer, applying pressure ranging from about 20 to about 400
psig at a temperature ranging from about 20.degree. C. to about
80.degree. C. above the glass transition (Tg) of at least one layer
of the copolyester for a period of time ranging from about 0.5
minutes to about 120 minutes to form the laminated article, wherein
the temperature at an interface of the first layer and the second
layer is equal to or greater than the Tg of at least one of the
first layer and the second layer, and wherein the copolyester has
an inherent viscosity (IV) ranging from about 0.5 to about 1.2
dL/g, when measured at 25.degree. C. using 0.50 grams of polymer
per 100 mL of a solvent consisting of 60 weight percent phenol and
40 weight percent tetrachloroethane.
[0086] In one aspect the invention relates to a laminated article
comprising a first layer and a second layer, each layer
independently comprising a copolyester layer, wherein at least one
layer further comprising a branching agent, and an electrically
energized device between the first and second layer, wherein the
copolyester has an inherent viscosity (IV) ranging from about 0.5
to about 1.2 dL/g, when measured at 25.degree. C. using 0.50 grams
of polymer per 100 mL of a solvent consisting of 60 weight percent
phenol and 40 weight percent tetrachloroethane and wherein the
article is prepared by applying pressure ranging from about 20 to
about 400 psig at a temperature ranging from about 20.degree. C. to
about 80.degree. C. above the glass transition (Tg) of at least one
layer of the copolyester for a period of time ranging from about
0.5 minutes to about 120 minutes to form the laminated article,
wherein the temperature at an interface of the first layer and the
second layer is equal to or greater than the Tg of at least one of
the first layer and the second layer.
[0087] In one aspect of the invention the electrically energized
device comprises an LEC have a color temperature ranging from 7500
to 11,000 degrees Kelvin or 5000 to 11,000 degrees Kelvin or 5000
to 8000 degrees Kelvin or 5000 to 7500 degrees Kelvin. In one
embodiment of the invention, the electrically energized device
comprises an LEC powered to illuminate from 100 cd/m.sup.2 to 200
cd/m.sup.2, or 100 cd/m.sup.2 to 300 cd/m.sup.2, or 200 cd/m.sup.2
to 300 cd/m.sup.2.
[0088] In one aspect of the invention, the perimeter frame does not
substantially overlap with the electrically energized device
encapsulated in the laminate structure, which means the frame does
not overlap more than about 1.0 inch or preferably about 0.5 inch
per side or edge or circumference of the electrically energized
device.
[0089] In one aspect of the invention, the processes result in a
flow of the polymer layers that is less than the flow that induces
fractures in the electrically energized device. For example, in LEC
the fractures appear as striations in the LEC surface and cause
reduced light output or failure of the LEC. These striations are
most easily seen on the non-illuminating side of the LEC panel,
especially in configurations where the metalized shielding film has
been removed prior to encapsulation.
[0090] In one aspect of the invention, the processes result in a
flow of the polymer layers that is less than the flow that induces
burn-through in the electrically energized device. For example, pin
point burn-through in an LEC results in holes burned in the LEC
when energized. The burn-through may also cause delamination near
the burn-through.
[0091] In one aspect of the invention, the processes further
comprise providing a power supply to the electrically energized
device to form an electrically energized system. In another aspect
of the invention, the articles further comprise a power supply to
the electrically energized device to form an electrically energized
system.
[0092] In one aspect of the invention, the first layer and the
second layer comprise different polymers. In another aspect of the
invention, the first layer and the second layer independently
comprise different copolyesters.
BRIEF DESCRIPTION OF THE DRAWINGS
[0093] FIG. 1a is the top view of an encapsulation layup showing
optional shims around an LEC panel.
[0094] FIG. 1b is a side view of half of an encapsulation
layup.
[0095] FIG. 2 is a top view of an encapsulation layup having a
perimeter lamination press.
DETAILED DESCRIPTION
[0096] The present invention may be understood more readily by
reference to the following detailed description of certain
embodiments of the invention, Figures and the working examples. In
accordance with the purpose(s) of this invention, certain
embodiments of the invention are described in the Summary of the
Invention and are further described herein below. Also, other
embodiments of the invention are described herein.
[0097] Unless otherwise indicated, all numbers expressing
quantities of ingredients, properties such as molecular weight,
reaction conditions, and so forth used in the specification and
claims are to be understood as being modified in all instances by
the term "about." Accordingly, unless indicated to the contrary,
the numerical parameters set forth in the following specification
and attached claims are approximations that may vary depending upon
the desired properties sought to be obtained by the present
invention. At the very least, each numerical parameter should at
least be construed in light of the number of reported significant
digits and by applying ordinary rounding techniques. Further, the
ranges stated in this disclosure and the claims are intended to
include the entire range specifically and not just the endpoint(s).
For example, a range stated to be 0 to 10 is intended to disclose
all whole numbers between 0 and 10 such as, for example 1, 2, 3, 4,
etc., all fractional numbers between 0 and 10, for example 1.5,
2.3, 4.57, 6.1113, etc., and the endpoints 0 and 10. Also, a range
associated with chemical substituent groups such as, for example,
"C.sub.1 to C.sub.5 hydrocarbons", is intended to specifically
include and disclose C.sub.1 and C.sub.5 hydrocarbons as well as
C.sub.2, C.sub.3, and C.sub.4 hydrocarbons. Notwithstanding that
the numerical ranges and parameters setting forth the broad scope
of the invention are approximations, the numerical values set forth
in the specific examples are reported as precisely as possible. Any
numerical value, however, inherently contains certain errors
necessarily resulting from the standard deviation found in their
respective testing measurements.
[0098] The term "polyester", as used herein, is intended to include
"copolyesters" and is understood to mean a synthetic polymer
prepared by the reaction of one or more difunctional carboxylic
acids and/or multifunctional carboxylic acids with one or more
difunctional hydroxyl compounds and/or multifunctional hydroxyl
compounds. Typically the difunctional carboxylic acid can be a
dicarboxylic acid and the difunctional hydroxyl compound can be a
dihydric alcohol such as, for example, glycols and diols. The term
"glycol" as used in this application includes, but is not limited
to, diols, glycols, and/or multifunctional hydroxyl compounds.
Alternatively, the difunctional carboxylic acid may be a hydroxy
carboxylic acid such as, for example, p-hydroxybenzoic acid, and
the difunctional hydroxyl compound may be an aromatic nucleus
bearing 2 hydroxyl substituents such as, for example, hydroquinone.
The term "residue", as used herein, means any organic structure
incorporated into a polymer through a polycondensation and/or an
esterification reaction from the corresponding monomer. The term
"repeating unit", as used herein, means an organic structure having
a dicarboxylic acid residue and a diol residue bonded through a
carbonyloxy group. Thus, for example, the dicarboxylic acid
residues may be derived from a dicarboxylic acid monomer or its
associated acid halides, esters, salts, anhydrides, or mixtures
thereof. Furthermore, as used in this application, the term
"diacid" includes multifunctional acids such as branching agents.
As used herein, therefore, the term dicarboxylic acid is intended
to include dicarboxylic acids and any derivative of a dicarboxylic
acid, including its associated acid halides, esters, half-esters,
salts, half-salts, anhydrides, mixed anhydrides, or mixtures
thereof, useful in a reaction process with a diol to make
polyester. As used herein, the term "terephthalic acid" is intended
to include terephthalic acid itself and residues thereof as well as
any derivative of terephthalic acid, including its associated acid
halides, esters, half-esters, salts, half-salts, anhydrides, mixed
anhydrides, or mixtures thereof or residues thereof useful in a
reaction process with a diol to make polyester. The terms
"polyacrylates", "polyacrylics", "acrylates" and "acrylics" are
used interchangeably to indicate polymeric materials derived from
monomers including, but not limited to, methyl methacrylate, methyl
acrylate, acrylonitrile, and acrylic acid. The term
"thermocompressive" refers to a process of applying both heat and
pressure during the lamination process.
[0099] The electrically energized devices include, but are not
limited to, light emitting capacitors (LEC's), light emitting
diodes (LED's), printed "circuit boards" that emit light when
energized, electrochromic layers, photovoltaics, transmitters,
receivers, antennas, electromagnets, electrodes and smart sensors
capable of detecting wind speed and direction, temperature,
pressure, relative humidity, rainfall, motion, radiation, specific
chemical species or combinations thereof. Furthermore, a light
emitting panel, comprising an electrically energized device, which
typically emits light over its entire surface area, can be altered
such that only portions of the panel emit light. This can be
accomplished by physically removing (e.g., die cutting, laser
cutting, etc.) sections of the electrically energized device from
the panel or by applying the luminescent phosphor in the shape of
specific patterns such that only the intended shape fluoresces. In
some embodiments two LECs or other electrically energized devices
can be encapsulated back-to-back such that both sides of the panels
are "active," i.e., perform the function of the device.
[0100] For example, certain embodiments of the present invention
may comprise a flat, flexible light panel made from light emitting
capacitors. This flat, flexible light panel technology involves a
parallel plate capacitor (two plates make up one parallel plate
capacitor) which causes a sandwiched layer of "phosphor" to
fluoresce when energized. This flexible light panel is relatively
fragile when exposed to outdoor conditions and needs additional
protection to survive in these environments such as the protection
provided by the present invention.
[0101] The thermoplastic articles of this invention can be used,
for example, in the manufacture of billboard signage, backlit bus
advertisement, street furniture, bus shelters, POP
(point-of-purchase) displays, flooring, kiosks, smart sensors,
decorative walls, partitions, glazing applications and other areas,
especially where backlighting is important. In one aspect of the
present invention, the thermoplastic articles are thermoformable
according to methods known in the art of thermoforming.
[0102] As shown in FIG. 1a an encapsulation layup may use shims "f"
around an LEC panel "e" to reduce or eliminate gaps between the
encapsulation sheets, which reduces or eliminates air trapped
during the encapsulation process. These shims are typically clear
polymeric films of the same composition as the upper and/or lower
sheet materials and are typically of about the same thickness as
the LEC panel.
[0103] Air entrapment abatement techniques include, but are not
limited to, using matte sheet, with the matte side facing the
encapsulated item, with an "Ra" or surface roughness measurement of
about 110 micro inches, where the preferred surface roughness value
depends on the type of inclusion being encapsulated, or using
vacuum assisted air removal, such as vacuum bagging techniques, or
by inserting "glass sheen" or similar fabrics to create channels
for air escape, where the fabrics are almost transparent after
encapsulation.
[0104] As shown in FIG. 1b, layer "a" is a padding that used to
equalize the platen pressure. Layer "a" is used for platens that
are not completely flat or that deflect or bow when pressure is
applied. Layer "b" is a metallic caul plate. Layer "c" is a release
film or paper. Layer "d" is a polymeric sheet with optional matte
surface facing the LEC panel to aid air removal. Layer "e" is a LEC
(light emitting capacitor) panel, for example an 8.5''.times.11''
LEC. For panels greater than about 10 mils thick, optional
polymeric film shims (layer "f") can be used to equalize the
thickness across the laminate surface further aiding air removal.
FIG. 1a shows an electrical lead "h" extending beyond the edge of
the lamination. The electrical plug can also be molded into the
laminate using conventional techniques. To complete the layup,
repeat layers "d" through "a" in reverse order on top of the LEC
panel (top section of the layup not shown).
[0105] As shown in FIG. 2, layers "a," "b," "c," "d," and "e" are
as described for FIG. 1a. Layer "g" is typically a polished chrome
plate of about the same thickness or several mils thicker than the
LEC panel with center removed from the chrome plate. During the
layup, layer "g" is inserted between layers "c" and "d" so that the
plate of layer "g" is not encapsulated.
[0106] In some embodiments of the present invention, a metallic
frame is used to preferentially redistribute the pressure to the
edges of the laminate around the panel. Such a process, using a
pressure frame with the center removed, in some embodiments
according to the present invention allows even higher temperature
and pressure conditions applied to the perimeter of the laminated
structure, since the relatively fragile panel doesn't experience
the same conditions. If the metal frame is several mils thicker
than the LEC panel, then the panel experiences essentially no
pressure and is laminated in a cavity or pocket. This perimeter
frame process is advantageous for pressure-sensitive electrical
structures, or objects that become pressure-sensitive at elevated
temperatures by applying a reduced force on the pressure-sensitive
portion of the laminated structure. In some embodiments using this
perimeter frame process the thermocompressive lamination techniques
discussed herein, except using a 15 to 50 mil thick metal polished
"frame" or pressure plate 0.5 to 12 inches, or 0.5 to 10 inches, or
1 to 8 inches, or 1 to 6 inches, or 1 to 3 inches wide on all sides
(center cut out), or wider depending on the width of the frame
needed, to preferentially concentrate the force to the lamination
perimeter and away from the pressure-sensitive structure. For
encapsulated items having a thickness greater than 50 mils, then a
correspondingly thicker pressure plate used.
[0107] In one aspect the present invention also involves the
lamination of an electrical plug into the final structure in which
the electric plug, "h" in FIG. 1, extends beyond the sheet of the
encapsulated structure. The electrically energized structure often
needs to be physically connected to a power source which may be any
conventional power supply, such as an inverter. A low-profile
(i.e., relatively flat) connector can be encapsulated into the
laminate structure at the edge for an aesthetically pleasing, easy
to install panel. In one embodiment of the present invention, the
lamination method described herein encapsulates the desired edges
on a plug when the plug is included in the layup. Alternatively,
the sheet can be notched or cut out such that the plug is recessed
at the laminate edge in the layup prior to sealing. A lamination
tool can also be devised to ensure proper access to the plug face
after lamination. For example, if a male-type plug is part of the
encapsulation, the lamination tool would involve encapsulation with
a female-type of tool joined to the male plug such that the male to
female connection is close to the edge of the layup. Release
sprays, films or female part material composition could be used to
aid lamination tool removal after part cooling.
[0108] The sheet material from which the upper (or outer) layer or
surface is formed generally has a thickness in the range of about
0.015-0.375 inch, preferably in the range of about 0.030-0.125
inch. The sheet material from which the lower (or backing) layer or
surface is formed typically has a thickness in the range of
0.015-0.375 inch, preferably in the range of about 0.030-0.125
inch.
[0109] In one aspect of the present invention, the thermoplastic
article of the present invention may be produced by subjecting the
laminate to temperatures and pressures sufficient to cause the
upper or lower sheet materials to bond (or fuse) around the
electrically energized layer. Although the upper and lower sheet
may also bond to the electrically energized layer, this is not
required for the present invention. However, temperatures which
cause decomposition, distortion, or other undesirable effects in
the finished article or sheet material, should be avoided. The
lamination temperatures are typically measured at the interface of
the sheets being laminated together. Typically, the bonding
temperatures are in the range of about 80 to 218.degree. C. (176 to
425.degree. F.), preferably in the range of about 82 to 118.degree.
C. (180 to 245.degree. F.). For certain embodiments of the
invention, the temperature has a lower limit of 80, 90, 100, 110,
120, 130, 140, 150, 160, 170, 180, 190, 200, 210, or 220.degree. C.
The temperature has an upper limit of 233, 220, 210, 200, 190, 180,
170, 160, 150, 140, 130, 120, 110, 100, or 90.degree. C. For
various embodiments of the invention the range of temperature may
be any combination of the lower limit of temperature with any upper
limit of temperature. The pressures utilized in the bonding or
laminating of the thermoplastic article of the invention preferably
are in the range of about 0.034 to 2.41 MPa (about 5 to 350 pounds
per square inch gauge ("psig")). For certain embodiments of the
invention, the pressure has a lower limit of 5, 10, 20, 30, 40, 50,
60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 175, 200, 225, 250,
275, 300 or 325 psig.). For certain embodiments of the invention,
the pressure has an upper limit of 10, 20, 30, 40, 50, 60, 70, 80,
90, 100, 110, 120, 130, 140, 150, 175, 200, 225, 250, 275, 300, 325
or 350 psig. For various embodiments of the invention the range of
pressure may be any combination of the lower limit of pressure with
any upper limit of pressure.
[0110] In certain embodiments according to the present invention,
the temperature at the interface of the laminated sheets ranges
from about 100 to about 160.degree. C., or from about 110 to about
160.degree. C., or from about 120 to about 160.degree. C., or about
130 to about 160.degree. C., or about 140 to about 160.degree. C.,
or about 150 to about 160.degree. C. In certain embodiments, the
temperature at the laminated sheets ranges from about 40 to about
80.degree. C. above the Tg of at least one of the sheets, or from
about 50 to about 80.degree. C. above the Tg of at least one of the
sheets, or from about 60 to about 80.degree. C. above the Tg of at
least one of the sheets, or from about 70 to about 80.degree. C.
above the Tg of at least one of the sheets.
[0111] In certain embodiments, the temperature at the interface of
the laminated sheets ranges from about 10.degree. C. below the Tg
of at least one of the laminated sheets to about 80.degree. C.
above the Tg of at least one of the laminated sheets. In certain
embodiments, the temperature at the interface of the laminated
sheets ranges from about 10.degree. C. below the Tg of at least one
of the laminated sheets to about 80.degree. C. above the Tg of both
of the laminated sheets.
[0112] In certain embodiments according to the present invention,
the temperature at the interface of the laminated sheets is
maintained at the desired setpoint for a time ranging from about
0.5 minutes to about 1.5 minutes, or 0.5 minutes to about 2.0
minutes, or 0.5 to about 3 minutes or, about 0.5 minutes to 4.0
minutes. In certain embodiments according to the present invention,
the temperature at the interface of the laminated sheets is
maintained at the desired setpoint for a time ranging from about 5
minutes to about 10 minutes, or 10 minutes to about 20 minutes, or
10 to about 30 minutes or, about 10 minutes to 40 minutes.
[0113] In other embodiments according to the present invention, the
temperature at the interface of the laminated sheets is maintained
at the desired setpoint for a time ranging from about 0.5 minutes
to about 120 minutes, or 0.5 minutes to about 60 minutes, or 0.5 to
about 45 minutes or, about 0.5 minutes to 30 minutes. In other
embodiments according to the present invention, the temperature at
the interface of the laminated sheets is maintained at the desired
setpoint for a time ranging from about 1 minute to about 120
minutes, or 1 minute to about 60 minutes, or 1 minute to about 45
minutes or, about 1 minute to 30 minutes. In other embodiments
according to the present invention, the temperature at the
interface of the laminated sheets is maintained at the desired
setpoint for a time ranging from about 5 minutes to about 120
minutes, or 5 minutes to about 60 minutes, or 5 minutes to about 45
minutes or, about 5 minutes to 30 minutes. In other embodiments
according to the present invention, the temperature at the
interface of the laminated sheets is maintained at the desired
setpoint for a time ranging from about 10 minutes to about 120
minutes, or 10 minutes to about 60 minutes, or to about 45 minutes
or, about 15 minutes to 30 minutes.
[0114] In certain embodiments according to the present invention,
the pressure on the laminate sheets ranges from about 20 to about
400 psig, or about 40 to 400 psig, or about 50 psig to about 400
psig, or about 20 to about 150 psig, or about 40 to about 150
psig.
[0115] The temperature for bonding the thermoplastic articles will
vary depending, for example, on the particular material or blend
employed and the thickness of the sheet materials used, and may be
determined by those skilled in the art using the disclosures
herein. The pressure will vary depending on the pressure
sensitivity of the electrical structure being encapsulated. LEC
panels, in one example, are pressed at approximately 0.10 MPa (15
psi). The laminate is held at the appropriate temperature and
pressure for about 5 to 45 minutes, or until such time as a bond is
formed between the upper and lower sheet materials. After 5 to 45
minutes, the bonded/fused thermoplastic article is allowed to cool
under pressures from about 0.034 to 2.41 MPa (about 5 to 350 psi),
preferably about 0.10 MPa (15 psi), until it cools below the glass
transition temperature of the sheet material. In certain
embodiments according to the present invention, during the bonding
process, the sheet material may be bonded or fused to the
electrically energized device without the use of an adhesive.
[0116] The residence times of 5 to 45 minutes are generally
applicable to single laminates layup configurations. Multiple
laminate layups, stacked vertically and separated by release papers
and caul plates, can also be constructed such that multiple
laminates are produced in just one heated platen opening. The
residence times for these multiple layup configurations may exceed
45 minutes. Proper residence times for multiple layup
configurations may be determined by one of ordinary skill using the
disclosures herein. The lower limit of residence time may be 5, 10,
15, 20, 25, 30, or 40 minutes. The upper limit of residence time
may be 45, 40, 35, 30, 25, 20, 15, or 10 minutes. For various
embodiments of the invention the range of residence times may be
any combination of the lower limit of residence time with any upper
limit of residence time.
[0117] The relatively low forces used in the thermocompressive
lamination of these pressure-sensitive electrical structures may
cause air entrapment. Typical air removal methods include
lamination under a vacuum; pre-drying the raw materials; or
creating channels for air escape, such as a matte texture on the
sheet surface, matte textured release paper, or including a "glass
sheen" fabric (available from Danzian) between areas prone to air
entrapment. For thicker panels (about 10 mils or thicker),
polymeric thin film shims can be added around the article to be
encapsulated to further aid air removal.
[0118] For temperature-sensitive objects, additional insulating
layers can be added to further protect the sensitive portions of
the panel. The insulating layers may be an interior layer that
becomes a part of the finished laminated panel or the insulating
layers may be external layers that are removed when the laminated
panel is removed from the lamination press.
[0119] In one aspect the invention relates to a thermoplastic
article having an electrically energized device obtained by
applying heat and pressure to a laminate comprising, (1) at least
one electrically energized device comprising light emitting
capacitors (LECs), light emitting diodes (LED's), printed "circuit
boards" that emit light when energized, electrochromic layers,
photovoltaics, transmitters, receivers, antennas, electromagnets,
electrodes and smart sensors capable of detecting wind speed and
direction, temperature, pressure, relative humidity, rainfall,
motion, radiation, specific chemical species or combinations
thereof and (2) at least one lower sheet and upper sheet material;
wherein the upper or lower sheet materials are formed from a
polyester.
[0120] In one aspect the invention relates to a thermoplastic
article having an electrically energized device obtained by
applying heat and pressure to a laminate comprising, (1) at least
one electrically energized device comprising light emitting
capacitors (LECs), light emitting diodes (LED's), printed "circuit
boards" that emit light when energized, electrochromic layers,
photovoltaics, transmitters, receivers, antennas, electromagnets,
electrodes and smart sensors capable of detecting wind speed and
direction, temperature, pressure, relative humidity, rainfall,
motion, radiation, specific chemical species or combinations
thereof; and (2) at least one lower sheet and upper sheet material;
wherein the upper or lower sheet materials are formed from a
polyester, polyacrylate, polycarbonate or a miscible
polyester/polycarbonate blend, wherein the lamination process uses
a perimeter frame, as described above, and the device having a
surface area ranging from greater than about 1 square foot (0.93
square meters) and less than about 120 square feet (11.2 square
meters) and wherein the polyester layers have a flow during
encapsulation less than the flow that induces fractures in the
electrically energized device.
[0121] In one aspect the invention relates to a thermoplastic
article having an electrically energized device obtained by
applying heat and pressure to a laminate comprising, (1) at least
one electrically energized device comprising light emitting
capacitors (LECs), light emitting diodes (LED's), printed "circuit
boards" that emit light when energized, electrochromic layers,
photovoltaics, transmitters, receivers, antennas, electromagnets,
electrodes and smart sensors capable of detecting wind speed and
direction, temperature, pressure, relative humidity, rainfall,
motion, radiation, specific chemical species or combinations
thereof; and (2) at least one lower sheet and upper sheet material;
wherein the upper or lower sheet materials are formed from a
polyester, polyacrylate, polycarbonate or a miscible
polyester/polycarbonate blend, wherein the lamination process uses
a perimeter frame, as described above, and the device having a
surface area ranging from greater than about 1 square foot (0.93
square meters) and less than about 120 square feet (11.2 square
meters) and wherein the polyester layers have a flow during
encapsulation less than the flow that induces burn-through in the
electrically energized device.
[0122] The present invention relates to thermoplastic articles
containing or comprising a branching agent to reduce undesirable
flow during the lamination processes and methods of making the
laminated articles. The use of branching agents unexpectedly
permits sufficient flow for the lamination processes described
herein. Previously it was believed that the use of branching agents
in lamination processes, as described herein, would have required
temperatures, pressures and/or cycle times that would have been
prohibitive for economic reasons or because of damage to the
laminated articles or inclusions.
[0123] In certain embodiments according to the present invention,
the reduction in flow of the first layer and the second layer of
inventive articles, as measured by the change of area of the
layers, decrease more than about 15% or about 25% or about 27% or
about 30% or about 33% or about 35% or about 36% or about 40% or
about 42% or about 50% or about 52% or about 55% or about 60% or
about 65% or about 70% or about 75% or about 78% or about 80% or
about 85% or about 90% or about 95% or about 100% or about 105% or
about 108% relative to similar copolyester layers without the
branching agent during the lamination. The reduction in flow is
determined by measuring the area of the sheets prior to lamination
and after lamination. The change in area for the sheets with the
branching agent is subtracted from the area for the sheets without
the branching agent and the difference is divided by the change in
area for the sheets with the branching agent. Examples are shown in
Table 1.
Reduction in flow (%)=[Change in area of sheet without branching
agent-Change in area of sheet with branching agent]/Change in area
of sheet with branching agent.
[0124] In one aspect the invention relates to branching agents
comprising about 0.05 to about 0.75 wt %, or about 0.5 to about
0.50 wt %, or about 0.5 to about 0.25 wt % of the polyester layer,
based on the total weight of the polyester layer.
[0125] In one embodiment of the invention suitable polyesters
include copolyesters commercially available from Eastman Chemical
Company as PETG Copolyester. These copolyesters comprise repeating
units of diacid residues and diol residues. At least 80 mole
percent of the diacid residues are terephthalic acid residues. The
diacid component of the copolyesters optionally may comprise up to
20 mole percent of one or more other dicarboxylic acid such that
the sum of the dicarboxylic acid units is equal to 100 mol percent.
Examples of such other dicarboxylic acids include phthalic acid,
isophthalic acid, 1,4-, 1,5-, 2,6- or 2,7-naphthalenedicarboxylic
acid, 1,3- or 1,4-cyclohexanedicarboxylic acid (which may be cis,
trans or a mixture thereof), cyclohexanediacetic acid,
trans-4,4'-stilbenedicarboxylic acid, 4,4'-oxydibenzoic acid, 3,3'-
and 4,4'-bi-phenyldicarboxylic acids and aliphatic dicarboxylic
acids such as malonic, succinic, glutaric, adipic, pimelic,
suberic, azelaic, sebacic, nonane, decane, and dodecanedicarboxylic
acids. The "residue" of the dicarboxylic acids described herein is
that portion of the diacid which constitutes a portion of a diester
of the diacid. The diacid residues may be derived from the
dicarboxylic acid, dialkyl esters thereof, e.g., dimethyl
terephthalate and bis(2-hydroxyethyl)terephthalate, acid chlorides
thereof and, in some cases, anhydrides thereof.
[0126] In one embodiment of the present invention, the diol
component of the copolyesters comprises from 98 to 1 mole percent
ethylene glycol residues and 2 to 99 mol percent
1,3-cyclohexanedimethanol and/or 1,4-cyclohexanedimethanol. Up to
20 mole percent of the diol component may be made up of the
residues of one or more diols other than ethylene glycol and
cyclohexanedimethanol such that the sum of all diol residues is 100
mole percent. Examples of such additional diols include
cycloaliphatic diols having 3 to 16 carbon atoms and aliphatic
diols having 3 to 12 carbon atoms. Specific examples of such other
diols include, but are not limited to, 1,2-propanediol,
1,3-propanediol, neopentyl glycol, 2-methyl-1,3-propanediol,
1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol,
2,2,4,4-tetramethyl-1,3-cyclobutanediol (trans-, cis- or mixtures
thereof), and p-xylylene glycol. The copolyesters also may be
modified with minor amounts of polyethylene glycols or
polytetramethylene glycols to enhance elastomeric behavior, e.g.,
polyethylene glycols and polytetramethylene glycols having weight
average molecular weights in the range of about 500 to 2000. In one
embodiment of the present invention, the diol component of the
copolyesters consists essentially of residues of ethylene glycol
and 1,4-cyclohexanedimethanol wherein the mole ratio of ethylene
glycol residues:1,4-cyclohexanedimethanol residues is about 10:90
to about 90:10, or preferably about 60:40 to about 80:20 or 38:62
to about 88:12.
[0127] In one embodiment of the invention, the diol portion of the
polyester comprises ethylene glycol and 1,4- or
1,3-cyclohexanedimethanol (cis-, trans-, and mixtures thereof). In
another embodiment of the invention, the diol portion of the
polyester consists essentially of ethylene glycol and 1,4- or
1,3-cyclohexanedimethanol (cis-, trans-, and mixtures thereof). In
one embodiment of the invention, the diol portion of the polyester
comprises neopentyl glycol and 1,4- or 1,3-cyclohexanedimethanol
(cis-, trans-, and mixtures thereof). In another embodiment of the
invention, the diol portion of the polyester consists essentially
of neopentyl glycol and 1,4- or 1,3-cyclohexanedimethanol (cis-,
trans-, and mixtures thereof). In one embodiment of the invention,
the diol portion of the polyester comprises ethylene glycol and
2-methyl-1,3-propanediol. In another embodiment of the invention,
the diol portion of the polyester consists essentially of ethylene
glycol and 2-methyl-1,3-propandediol. In one embodiment of the
invention, the diol portion of the polyester comprises ethylene
glycol and neopentyl glycol. In another embodiment of the
invention, the diol portion of the polyester consists essentially
of ethylene glycol and neopentyl glycol. In another embodiment of
the invention, the diol portion of the polyester comprises 1,3- and
1,4-cyclohexanedimenthanol (cis-, trans-, and mixtures thereof) and
2-methyl-1,3-propandediol. In another embodiment of the invention,
the diol portion of the polyester consists essentially of 1,3- and
1,4-cyclohexanedimenthanol (cis-, trans-, and mixtures thereof) and
2-methyl-1,3-propandediol. In another embodiment of the invention,
the diol portion of the polyester comprises neopentyl glycol and
2-methyl-1,3-propandediol. In another embodiment of the invention,
the diol portion of the polyester consists essentially of neopentyl
glycol and 2-methyl-1,3-propandediol.
[0128] Polycarbonates useful in this invention comprise the
divalent residue of dihydric phenols bonded through a carbonate
linkage and are represented by structural formulae I and II.
##STR00001##
wherein:
[0129] A denotes an alkylene group with 1 to 8 carbon atoms; an
alkylidene group with 2 to 8 carbon atoms; a cycloalkylene group
with 5 to 15 carbon atoms; a cycloalkylidene group with 5 to 15
carbon atoms; a carbonyl group; an oxygen atom; a sulfur atom;
--SO-- or --SO.sub.2; or a radical conforming to e and g both
denote the number 0 to 1; Z denotes F, Cl, Br or C1-4.alkyl; and if
several Z radicals are substituents in one aryl radical, they may
be identical or different from one another; d denotes an integer of
from 0 to 4; and f denotes an integer of from 0 to 3.
[0130] By the term "alkylene" is meant a bivalent saturated
aliphatic radical wherein the two valences are on different carbon
atoms, e.g., ethylene; 1,3-propylene; 1,2-propylene; 1,4-butylene;
1,3-butylene; 1,2-butylene, amylene, isoamylene, etc. By the term
"alkylidene" is meant a bivalent radical wherein the two valences
are on the same carbon atoms, e.g., ethylidene, propylidene,
isopropylidine, butylidene, isobutylidene, amylidene, isoamylidene,
3,5,5,-trimethylhexylidene. Examples of "cycloalkylene" are
cyclopropylene, cyclobutylene, and cyclohexylene. Examples of
"cycloalkylidene" are cyclopropylidene, cyclobutylidene, and
cyclohexylidene. Examples of C1-4 alkyl are methyl, ethyl, propyl,
isopropyl, butyl, and isobutyl.
[0131] Typical of some of the dihydric phenols employed are
bis-phenols such as 2,2-bis-(4-hydroxyphenyl)-propane (bisphenol
A), 3,3,5-trimethyl-1,1-bis(4-hydroxyphenyl)-cyclohexane,
2,4-bis-(4-hydroxyphenyl)-2-methyl-butane,
1,1-bis-(4-hydroxyphenyl)-cyclohexane,
alpha,alpha'-bis-(4-hydroxyphenyl)-p-diisopropylbenzene,
2,2-bis-(3-methyl-4-hydroxyphenyl)-propane,
2,2-bis-(3-chloro-4-hydroxyphenyl)propane,
bis-(3,5-dimethyl-4-hydroxyphenyl)-methane,
2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane,
bis-(3,5-dimethyl-4-hydroxyphenyl)-sulfide,
bis-(3,5-dimethyl-4-hydroxyphenyl)-sulfoxide,
bis-(3,5-dimethyl-4-hydroxyphenyl)-sulfone, dihydroxy-benzophenone,
2,4-bis-(3,5-dimethyl-4-hydroxyphenyl)-cyclohexane,
alpha,alpha'-bis-(3,5-dimethyl-4-hydroxyphenyl)-p-diisopropylbenzene
and 4,4'-sulfonyl diphenol. Other dihydric phenols might include
hydroquinone, resorcinol, bis-(hydroxyphenyl)-alkanes,
bis-(hydroxyphenyl)ethers, bis-(hydroxyphenyl)-ketones,
bis-(hydroxyphenyl)-sulfoxides, bis-(hydroxyphenyl)-sulfides,
bis-(hydroxyphenyl)-sulfones, and
alpha,alpha-bis-(hydroxyphenyl)diisopropylbenzenes, as well as
their nuclear-alkylated compounds. These and further suitable
dihydric phenols are described, for example, in U.S. Pat. Nos.
2,991,273; 2,999,835; 2,999,846; 3,028,365; 3,148,172; 3,153,008;
3,271,367; 4,982,014; 5,010,162 all incorporated herein by
reference. The polycarbonates of the invention may entail in their
structure, units derived from one or more of the suitable
bisphenols. The most preferred dihydric phenol is
2,2-bis-(4-hydroxyphenyl)-propane (bisphenol A).
[0132] The carbonate precursors are typically a carbonyl halide, a
diarylcarbonate, or a bishaloformate. The carbonyl halides include,
for example, carbonyl bromide, carbonyl chloride, and mixtures
thereof. The bishaloformates include the bishaloformates of
dihydric phenols such as bischloroformates of
2,2-bis(4-hydroxyphenyl)-propane, hydroquinone, and the like, or
bishaloformates of glycol, and the like. While all of the above
carbonate precursors are useful, carbonyl chloride, also known as
phosgene, and diphenyl carbonate is preferred.
[0133] The aromatic polycarbonates can be manufactured by any
processes such as by reacting a dihydric phenol with a carbonate
precursor, such as phosgene, a haloformate or carbonate ester in
melt or solution. Suitable processes are disclosed in U.S. Pat.
Nos. 2,991,273; 2,999,846; 3,028,365; 3,153,008; 4,123,436; all of
which are incorporated herein by reference.
[0134] In certain embodiments of the present invention, the
polycarbonates have a weight average molecular weight, as
determined by gel permeation chromatography, of about 10,000 to
200,000, preferably 15,000 to 80,000 and their melt flow index, per
ASTM D-1238 at 300.degree. C. is about 1 to 65 g/10 min, preferably
about 2 to 30 g/10 min. The polycarbonates may be branched or
unbranched. It is contemplated that the polycarbonate may have
various known end groups. These resins are known and are readily
available in commerce.
[0135] One or more branching agents may also be used in making the
polycarbonates of the invention. Branching agents, such as tri- and
tetrafunctional phenols and carbonic acids, as well as bisphenols
with carbonic acid side chains are typically used. An example might
include 1,4bis (4',4''-dihydroxytriphenylmethyl)benzene, and
trisphenol TC. Nitrogen-containing branching agents are also used.
Examples might include: cyanic chlorid and
3,3-bis(4-hydroxyphenyl)-2-oxo-2,3-dihydroindole.
[0136] Polyacrylates suitable in the context of the present
invention are polyacrylate ester polymers having repeating unit of
the Formula III:
##STR00002##
wherein R is either hydrogen, methyl or carboxyl groups and blends
thereof and wherein R1 includes hydrogen, methyl, ethyl and other
alkyl or cycloalkyl functional groups having 3 to 20 carbon atoms,
aminyl, hydroxyl, N-hydroxymethyl, epoxyl and dialkenyl functional
groups or blends thereof. Examples of the R1 portion are hydrogen,
methyl, ethyl, propyl, isopropyl, isopropyl, n-butyl, sec-butyl,
isobutyl, tert-butyl, hexyl, heptyl, 2-heptyl, 2-ethylhexyl,
2-ethylbutyl, dodecyl, hexadecyl, isobornyl, cyclohexyl,
t-butylaminoethyl, dimethylaminoethyl, 2-hydroxyethyl,
2-ethoxyethyl, N-hydroxymethyl, glycidyl or 1,4-butylene
dimethacryl functional groups.
[0137] Polyester/polycarbonate miscible blends suitable in the
context certain embodiments of the present invention comprise:
(a) 1 to 99 weight % of a polyester, comprising a diacid residue
component selected from the group consisting of aliphatic,
alicyclic, and/or aromatic dicarboxylic acids, wherein the aromatic
portion of said aromatic dicarboxylic acid has 6-20 carbon atoms,
wherein the aliphatic or alicyclic portion of said aliphatic or
alicyclic dicarboxylic acid has 3-20 carbon atoms, and a glycol
residue component comprising from 45 mole % to 100 mole %
1,4-cyclohexanedimethanol, and, optionally, at least one additional
aliphatic glycol having 2-20 carbon atoms; wherein the total mole
percentages for the glycol component equals 100 mole %. (b) 99 to 1
weight % of a polycarbonate; wherein the total combined weight
percentage of polyester and polycarbonate in the
polyester/polycarbonate blend equals 100 weight %. Suitable
polyester/polycarbonate blends are exemplified in U.S. Pat. No.
6,896,966.
[0138] In one embodiment the polyester/polycarbonate blend
composition suitable in the present invention comprises 50-90
weight % by weight of the polyester and 50-10 weight % by weight of
the polycarbonate. In another embodiment, the blend composition
comprises 60-80 weight % polyester and 40-20 weight % by weight
polycarbonate.
[0139] Polyesters particularly suitable in certain embodiments
having polyester/polycarbonate blends of the present invention are
polyesters having repeating unit of the Formula IV:
##STR00003##
wherein R is the residue of 1,4 cyclohexanedimethanol or a mixture
of 1,4 cyclohexanedimethanol and at least one aryl, alkane or
cycloalkane containing diol having 2 to 20 carbon atoms; and
wherein R1 is the decarboxylated residue derived from an aryl,
aliphatic, or cycloalkane containing diacid of 3 to 20 carbon
atoms. Examples of the diol portion, R, are ethylene glycol,
1,2-propylene glycol, 1,3-propanediol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 1,2- or 1,3-cyclohexanedimethanol,
neopentyl glycol, and 2,2,4,4 tetramethyl-1,3-cyclobutanediol. In
one embodiment the second glycol comprises ethylene glycol, and
mixtures thereof. Examples of the diacid portion, R1, are malonic,
succinic, glutaric, adipic, pimelic, suberic, azelaic, sebacic,
dodecanedioic, 1,4-, 1,5-, and 2,6-decahydronaphthalenedicarboxylic
acid, and cis- or trans-1,4-cyclohexanedicarboxylic acid. Examples
of useful aromatic dicarboxylic acids are terephthalic acid,
isophthalic acid, 4,4'-biphenyldicarboxylic, trans 3,3'- and trans
4,4 stilbenedicarboxylic acid, 4,4'-dibenzyldicarboxylic acid,
1,4-, 1,5'-, 2,3-, 2,6, and 2,7-naphthalenedicarboxylic acid.
Chemical equivalents of these diacids, and within the scope of the
present invention, include esters, alkyl esters, dialkyl esters,
diaryl esters, anhydrides, salts, acid chlorides, acid bromides,
and the like and are included within the scope of this invention.
In certain embodiments of the present invention, the preferred
dicarboxylic acids are terephthalic and isophthalic acid or
mixtures thereof. In certain embodiments, the preferred chemical
equivalent comprises dialkyl esters of terephthalic and isophthalic
acid. Mixtures of any of these acids or equivalents may be
used.
[0140] In certain embodiments, polyesters useful within the scope
of this invention comprise a polyester having from 40 to 100 mole
%, more preferably 60 to 80 mole % of 1,4-cyclohexanedimethanol
wherein the total mole percentages of the glycol component in the
polyester equal 100 mole %. The remainder of the glycol component
comprises any of the other glycols described herein but, in certain
embodiments, preferably ethylene glycol in the amount of 0 to 60
mole %, more preferably, 20 to 40 mole %. Although any diacid as
described herein may be used, 80 to 100 mole % terephthalic acid is
preferred for certain embodiment.
[0141] In another embodiment of polyester/polycarbonate miscible
blends, the polyester useful within the scope of this invention is
a polyester having from 100 mole % 1,4-cyclohexanedimethanol
wherein the total mole percentages of the glycol component in the
polyester equal 100 mole %. Also, in this particular embodiment, it
is preferred that isophthalic acid is present in the amount of 5 to
50 mole %, more preferably, 20 to 40 mole %. Although any diacid as
described herein may be used, it is preferred in certain
embodiments that terephthalic acid is present in the amount of 95
to 50 mole %.
[0142] Conventional polycondensation processes, well known in the
art, are used to prepare the polyesters useful in the present
invention. These include direct condensation of the acid(s) with
the diol(s) or by ester interchange using lower alkyl esters. In
one aspect, the inherent viscosity of the polyesters of the present
invention may range from about 0.5 to about 1.2 dL/g, about 0.4 to
about 1.0 dl/g or about 0.6 to about 0.9 dL/g at 25.degree. C.,
measured by dissolving about 0.50 g of the polyester in about 100
mL of a solvent consisting of 60% by weight phenol and 40% by
weight tetrachloroethane.
[0143] The polymerization reaction to form the polyesters useful in
the present invention may be carried out in the presence of one or
more conventional polymerization catalysts. Typical catalysts or
catalyst systems for polyester condensation are well known in the
art. Suitable catalysts are disclosed, for example, in U.S. Pat.
Nos. 4,025,492, 4,136,089, 4,176,224, 4,238,593, and 4,208,527, the
disclosures of which are herein incorporated by reference. Further,
R. E. Wilfong, Journal of Polymer Science, 54, 385, (1961)
describes typical catalysts, which are useful in polyester
condensation reactions. Preferred catalyst systems include Ti,
Ti/P, Mn/Ti/Co/P, Mn/Ti/P, Zn/Ti/Co/P, Zn/Al, and Li/Al. When
cobalt is not used in the polycondensation, copolymerizable toners
may be incorporated into the copolyesters to control the color of
these copolyesters so that they are suitable for applications in
which color may be an important property. In addition to the
catalysts and toners, other conventional additives, such as
antioxidants, dyes, etc., may be used in the copolyesterifications
in typical amounts.
[0144] In certain embodiments, one or more branching agents may
also be useful in making the polyesters useful in the present
invention. The branching agent can be one which provides branching
in the acid unit portion of the polyester, or in the glycol unit
portion, or it can be a hybrid. Illustrative of such branching
agents are polyfunctional acids, polyfunctional glycols and
acid/glycol hybrids. Examples include, but are not limited to, tri
or tetracarboxylic acids, such as trimesic acid, pyromellitic acid
and lower alkyl esters thereof and the like, and tetrols such as
pentaerythritol. Also triols such as trimethylolpropane or
dihydroxy carboxylic acids and hydroxydicarboxylic acids and
derivatives, such as dimethyl hydroxy terephthalate, and the like
are useful within the context of this invention. Trimellitic
anhydride is a preferred branching agent. The branching agents may
be used either to branch the polyester itself or to branch the
polyester/polycarbonate blend of the invention.
[0145] Polymer miscibility is defined herein as a polymer blend or
mixture forming a single phase.
[0146] Miscible polymer blends useful in this invention were first
disclosed in Research Disclosure 22921, May, 1983, which concerns
blends of polycarbonate with polyesters based on terephthalic acid
and a mixture of 1,4-cyclohexanedimethanol and ethylene glycol.
Similar miscible blends are disclosed in U.S. Pat. Nos. 4,786,692
and 5,478,896. Blends of polycarbonate with another family of
polyesters, those based on a mixture of terephthalic and
isophthalic acids with 1,4-cyclohexanedimethanol, are disclosed in
U.S. Pat. Nos. 4,188,314 and 4,391,954. British Patent
Specification 1,599,230 (published Jan. 16, 1980) discloses blends
of polycarbonate with polyesters of 1,4-cyclohexanedimethanol and a
hexacarbocyclic dicarboxylic acid. Mohn et al. reported on thermal
properties of blends of polyesters based on
1,4-cyclohexanedimethanol and terephthalic acid or
terephthalic/isophthalic acid mixtures with polycarbonate [J. Appl.
Polym. Sci., 23, 575 (1979)].
[0147] One embodiment of the invention is the laminate of the
invention consisting of an electrically energized layer (1) and
upper or lower sheet material (2), it is also within the scope of
this invention that there can be multiples of such laminates within
the same thermoplastic article, i.e., electrically energized layer,
upper or lower sheet material, electrically energized layer, upper
or lower sheet material, etc.
[0148] The polyesters useful in certain embodiments of this
invention maybe made by conventional melt processing techniques.
For example, pellets of the polyester may be mixed with pellets of
the polycarbonate and subsequently melt blended on either a single
or twin screw extruder to form a homogenous mixture.
[0149] The polyesters, polyacrylates, polycarbonates or
polyester/polycarbonate blends useful in various embodiments of the
invention may contain impact modifiers, UV stabilizers,
stabilizers, nucleating agents, extenders, flame retarding agents,
reinforcing agents, fillers, antistatic agents, antimicrobial
agents, antifungal agents, self-cleaning or low surface energy
agents, mold release agents, scents, colorants, antioxidants,
extrusion aids, slip agents, release agents, light diffusing
additives, carbon black, and other pigments, and the like all and
mixtures thereof which are known in the art for their utility in
polyesters, polyacrylates, polycarbonates or
polyester/polycarbonate blends. In particular, the use of
phosphorous based stabilizers for further color reductions, if
needed, is well known in the art.
[0150] The upper and lower sheet materials used in the manufacture
of the thermoplastic articles of the present invention may be the
same or different. For example, the upper and lower sheet materials
may be produced from different polyesters, polyacrylates,
polycarbonates or polyester/polycarbonate miscible blends (as
defined herein) or compositions that contain different additives,
e.g., pigment additives that alter the transparency of the
sheeting.
[0151] The sheet material used in the preparation of the
thermoplastic articles of the present invention may be transparent,
translucent, or one layer may be opaque, depending on the
particular aesthetic effect desired. The upper and lower sheet
materials may differ in degree of transparency or translucency and
also in color. When the upper and lower sheet materials are
produced from chemically dissimilar materials, the dissimilar
materials must be thermally compatible. As used herein, the term
"thermal compatibility" means that when layers of the sheet
materials are bonded together under conditions of elevated
temperature and pressure, the layers undergo approximately equal
thermal expansion or contraction such that the solid surface is
substantially planar.
[0152] Some electrical components may have a sensitivity to
moisture when exposed to outdoor environments. In addition to
pre-drying the raw materials, the encapsulation of additional
moisture barriers, such as a layer of EVOH or nanoclay-impregnated
metaxylene diamine ("MXD6"), may be required beyond the
copolyester, et al, sheeting already present. These barrier layers
can be added to the laminate layup as either a film or co-extruded
directly onto the plastic sheeting. Desiccants or other hydrophilic
moisture scavengers can also be encapsulated with the panels.
[0153] The composition and blends thereof constituting the sheet
materials used in the manufacture of the articles and sheeting of
the present invention may not be as hard or scratch resistant as
may be necessary or desired for certain end uses. For example, an
end use in which the exterior surface of the thermoplastic article
may be subjected to scratching or abrasion, i.e., in a wall
decoration, may require the application of an abrasion-resistant
coating to the exterior surface. For example, films consisting of
fluorinated hydrocarbons, poly(perfluoroethylene) such as TEDLAR
from duPont Chemical Company or oriented poly(ethylene
terephthalate) such as MYLAR from duPont Chemical Company may be
used to improve both chemical and abrasion resistance. The abrasion
resistant film typically has a thickness in the range of about
0.025 to 0.254 mm (0.001-0.01 inch), preferably about 0.051 to
0.178 mm (0.002-0.007 inch), and most preferably about 0.076 mm
(0.003 inch). However, abrasion resistant film thinner or thicker
than these ranges may be used since the thickness of such film is
limited only by the equipment available cost and functionality
considerations. An adhesive optionally may be used between the
thermoplastic sheet and the abrasion resistant film.
[0154] Alternatively, an abrasion resistant coating may be applied
to a plastic film and then the film bearing the abrasion resistant
coating may be laminated to one or both sides of the article of the
present invention. The film may be selected from a number of
thermoplastic materials compatible with the lamination process such
as poly(vinyl chloride), PETG copolyester, poly(ethylene
terephthalate), poly(methyl methacrylate), polycarbonate, miscible
polyester/polycarbonate blends, and the like.
[0155] The film thickness may range from 0.0025-0.381 mm
(0.001-0.015 inch) with a thickness of 0.0762-0.203 mm
(0.003-0.008) being most preferred. The coating may be selected
from a number of commercially-available materials such as
polyurethanes, fluorinated polyurethanes and silicones which are
cured by heat or they may be selected from materials that are cured
by ultraviolet (UV) or electron beam (EB) radiation. Such UV/EB
cured materials fall under the general class of acrylates and
modified acrylates that contain fluorine, silicone, epoxy,
polyester, polyether or caprolactone residues or functional groups.
The particular coating material selected will depend primarily on
the degree of abrasion resistance required. Application of the
liquid, heat- or UV/EB-curable precursor of the abrasion resistant
coating may be carried out according to conventional procedures and
usually is accomplished on a roll coating machine. The thickness of
the coating applied to a film generally is 0.0076-0.051 mm
(0.0003-0.002 inch) with thickness of about 0.0127 mm (0.0005 inch)
being most preferred. Primers or tie layers can also be used
between the hardcoat and film layer to promote adhesion.
[0156] These coatings may be applied in a manner similar to the
application of paints. The coatings exist either as predominantly
undiluted material with very little volatile content or as solvent-
or water-based materials. In addition to being applied to a film
that can be laminated to the structure as part of the process, they
may be applied directly to the finished product. Application may be
carried out by a variety of techniques such as roll, paint, spray,
mist, dip and the like.
[0157] The thermoplastic article or laminate, based on polyesters,
polyacrylates, polycarbonates or polyester/polycarbonate miscible
blends, can be subsequently shaped and thermoformed into a variety
of useful products. As an illustrative example, the thermoplastic
article can be thermoformed or otherwise shaped into curved
signage, backlit instrument panels, cellular phone panels, computer
keyboards, safety vests, flooring, shower doors, privacy
partitions, and tabletops and other furniture pieces. Depending on
the nature of the electrically energized device, the thermoplastic
articles of this invention may be formed, heat draped, or molded.
In addition, the articles of the present invention have an
appealing appearance with low density to facilitate transport and
installation of building materials produced there from.
[0158] In addition to the batch lamination method discussed herein,
continuous lamination techniques can also be employed. For example,
since LEC panels are flexible, they can be fed through the roll
stack on a sheet extrusion line to form an in-line lamination
process. The typical injection path is usually between the second
and third polished (or otherwise textured) rolls that the polymer
touches. This would involve the middle and top cooling rolls for
upright roll stacks with an upward product flow. To achieve proper
lamination, the LEC panels will need to be fed "face down" where
the illuminated side touches the plastic sheet being made. Proper
adhesion temperatures are between 175 to 425.degree. F., preferably
between 180 and 300.degree. F., controlled by the cooling rolls
which should operate with a low side-to-side temperature
differential of less than 20.degree. F., preferably less than
5.degree. F. In cases where true encapsulation is needed, multiple
materials can be fed into the roll stack. For example, pre-heated
plastic sheeting could be fed through the roll stack on a sheet
extrusion line along with the LEC panel such that the LEC panel is
entirely encapsulated.
[0159] Other continuous processes can also be envisioned, such as
continuously unwinding two rolls of plastic sheeting with the LEC
panels being fed between the two sheets. An oven or other heating
device would be needed to heat the plastic to the same temperatures
mentioned during the batch lamination process to achieve proper
adhesion. A set of pressurized nip rollers or similar pressure
application devices could then be used to achieve proper adhesion.
From an air removal standpoint, an in-line vacuum chamber or the
use of glass sheen and similar fabrics could be also be used,
similar to methods discussed for the batch lamination process. This
type of continuous process could also be devised where the
lamination is caused by means other than external heat. For
example, solvent bonding (entire sheet or just the edges) or edge
sealing (via frictional methods, targeted melting via laser or
other devices) are also possible.
[0160] To further optimize the process, the indium tin oxide (ITO)
or similar functional LEC layers could be applied directly to the
plastic sheet in either method previously discussed--in-line
lamination with a sheet extrusion line or the dual roll unwinding
processes. This process could simplify the overall structure by
reducing the total number of required layers in the LEC panel.
[0161] The method in Example 1 demonstrates a method to properly
encapsulate an electrically energized device in a panel using a
heated laminated press. Similar conditions be could obtained
without a heated laminating press by using a vacuum bagging
operation and an oven. The alternate method applies a low
"pressure," which is the pressure differential between atmospheric
pressure plus the weight of panel in multiple lamination stacks and
a vacuum on the inside of the bag. This entire vacuum bagged layup
is then put into an "autoclave" oven.
EXAMPLES
Example 1
[0162] The layup was constructed according to the following layered
arrangement on each side of the LEC panel: 60 mil rubber silicone
pad for pressure distribution, 30 mil polished metal plate,
"Ultracast patent" release paper, "Stratafilm" hardcoat film
(.about.5 mil thick), 118 mil Spectar.TM. copolyester plastic
sheeting (with matte surface toward the LEC panel to prevent air
entrapment, with the surface roughness or "Ra" value of 110 micro
inches), 17 mil CeeLite.TM. light emitting capacitor (LEC) panel.
The panel was framed with 15 mil Spectar film around its perimeter
to avoid air entrapment in this region. The layup was transferred
to a heated press with a top and bottom plate temperature set point
of 120.degree. C. A metal transfer plate was also used beneath the
layup to help properly position the structure in the press. The
press was closed around the structure using a setting of roughly
5,000 foot-pounds (which is slightly above contact pressure due to
the weight of the platens being raised). After approximately six
minutes (when the interfacial sheet temperature reaches about
230.degree. F.), the heat to the plates was turned off and the
cooling water turned on. When the interfacial sheet temperature
reached 130.degree. F., the layup was removed from the press for
inspection. The combined effect of directionally lower pressures,
short time and normal heat (normal for copolyester to copolyester
lamination) created a quality lamination that didn't harm the
encapsulated light panel, evidenced by the lack of pinpoint
burn-through that would otherwise appear upon energization and by
the lack of panel fracture lines caused by excessive copolyester
sheet, and therefore LEC panel, flow or deformation. In other
embodiments of the present invention, other methods could achieve
the same or similar conditions instead of using heated platens, for
example, the layups could be rolled into a convection oven to
achieve a similar effect.
Example 2
[0163] Follow Example 1, but with the layup under vacuum. The layup
was placed on an oversized flat metal transfer plate. The outermost
perimeter edge of the oversized transfer plate was framed with 1/2
inch wide vacuum sealant tape available from General Sealants. A
thin plastic film of Eastman's calendered GS5 was placed over the
entire layup and pressed into the sticky sealant tape, totally
sealing the structure. Pressure was reduced by puncturing the film
with a syringe attached to a vacuum source and evacuating the
sealed structure. A small square of vacuum sealant tape was placed
around the syringe to eliminate leakage around the puncture. The
vacuum was turned and left "on" during the heating and cooling
steps mentioned in Example 1.
Example 3
[0164] Conditions which prevent excessive copolyester sheet (and
therefore LEC panel) flow or deformation will make the desired
lamination without defects that become apparent upon energization,
for example, burn-through. Lamination parameters can be thought of
in terms of a 3-dimensional operating surface with axes of
temperature, pressure and time. The maximum operating surface for a
LEC panel is below that for copolyester to copolyester lamination
of non-temperature and/or non-pressure sensitive items or devices.
To illustrate, getting a half inch of expansion on the sides of the
polymer sheet during lamination is an indication that diffusive
polymer chain entanglements have occurred at the sheet to sheet
interface (a 12''.times.12'' sheeting deforms to
12.5''.times.12.5'' laminate, which is then trimmed to size). This
situation is perfectly acceptable for lamination of relatively
non-fragile items or devices, but not with LEC panels as fracture
lines and pinpoint defects will develop, as previously explained.
The lowering of either temperature, pressure or time (singly or in
combination) to make a laminate without flow is one acceptable
method to encapsulate LEC panels. In example 1, the pressure was
lowered and time reduced to reduce flow and sheet deformation.
According to the maximum operating surface concept, temperature can
be lowered at normal pressure and longer cycle times to achieve the
same effect. A specific example follows:
[0165] The layup was constructed according to the following layered
arrangement: 60 mil rubber silicone pad for pressure distribution,
30 mil polished metal plate, "Ultracast patent" release paper,
"Stratafilm" hardcoat film (.about.5 mil thick), 118 mil Spectar
copolyester plastic sheeting (with matte surface to prevent air
entrapment), 17 mil CeeLite light emitting capacitor (LEC) panel,
15 mil Spectar shim film around the CeeLite perimeter and continue
the reverse of above, from the plastic sheeting to rubber pad, to
complete the layup. The layup was transferred to a heated press
with a top and bottom plate temperature setpoint of 100.degree. C.
A metal transfer plate was used beneath the layup as needed to help
properly position the structure in the press. The press was closed
around the layup using a setting of roughly 20,000 foot-pounds of
pressure (about 140 psi for a 12''.times.12'' structure). After
approximately 30 minutes, the heat to the plates was turned off and
cooling water turned on. When the interfacial sheet temperature
reached 130.degree. F., the layup was removed from the press for
inspection. The combined effect of inventive selection of lower
temperature, longer time and normal pressure (normal for
copolyester to copolyester lamination) created a quality lamination
that didn't harm the encapsulated light panel, evidenced by the
lack of pinpoint burn-through that would otherwise appear upon
energization and by the lack of panel fracture lines caused by
excessive copolyester sheet, and therefore LEC panel, flow or
deformation.
[0166] Note that lamination conceptionally occurs in a
3-dimensional operating volume defined by pressure, temperature and
time. Without wishing to be bound by any theory applicants believe
that as the upper/maximum operating surface is approached, a
stronger lamination is made because of higher polymer chain
mobility leads to more chain entanglements and therefore a stronger
lamination. The goal is to maximize chain entanglements while
preventing excessive material flow or deformation.
Example 4
[0167] Example 3 was repeated except the platen temperature was at
105.degree. C., each Spectar sheet was 60 mils thick, the CeeLite
panel was only 9 mils thick (the shielding on the back side had
been removed), and the film shims used around the panel were 10
mils thick. The pressure was set at 90 psi with a time of 20
minutes in the heating cycle before cooling. This produced a
"perfect" panel without fracture lines or pinpoint
burn-through.
Example 5 Prophetic
[0168] Follow Example 1 except add a 5 mil thick film of EMAC, EVA,
EVOH, PUR or the like, around the LEC panel to reduce the
lamination temperature requirements and/or increase moisture
diffusion barrier properties to the encapsulated LEC panel.
Example 6
[0169] Example 1 was followed except a 30 mil thick metal "frame"
was included, one inch wide on all sides (center cut out), between
the polished metal plate and the Ultracast release paper on the
non-illuminated side (back side) of the LEC panel. This insert
transferred the pressure to the lamination perimeter and aided
bubble removal and lowered the pressure to the electrical
component, thus preventing pinpoint burn-through defects. The LEC
panel, prior to lamination, did not have any fracture lines or
pinpoint burn-throughs, so it was fully operational. However, since
the 30 mil frame was thick relative to the 17 mil LEC panel, a
pocket or cavity of about 12 mils was formed. The presence of a
pocket allowed to panel to wrinkle in the pocket, forming a fully
functioning yet wrinkled, aesthetically unpleasant encapsulated LEC
panel. Further experimentation with a thinner frame caused a
thinner pocket prevented panel wrinkling. Other experimentation
involved building up film layers behind the panel to fill the gap
in the cavity. Additionally, the LEC panel was adhered to the
polymer encapsulation sheet with a pressure-sensitive adhesive.
Even though a pocket was formed behind the panel, the laminated LEC
panel was unwrinkled and aesthetically pleasing because the air was
directed behind the panel instead of on the illuminated side.
Further, a clear polyethylene and then liquid oil film (in two
different sets of experiments) were placed on the illuminated side
of the LEC panel to ensure that no lamination occurred in these
areas.
[0170] Applicants believe that either changing the materials of
construction to prevent wrinkling, or making one layer of the LEC
panel wider than the others to be encapsulated in the metal framed
area (acting as anchor points) are expected to keep wrinkling or
distortion to an acceptable, and possible, a minimum level. In
summary, when the "pocket" method is used, the LEC panel may be
fully functional yet have unpleasant aesthetic effects that will be
mitigated by any of the methods described in this example.
Example 7 Prophetic
[0171] Follow Example 1 except replace the light emitting panel
(which typically emits light over its entire surface area) with a
similar panel that has been altered such that only portions of the
panel emit light. For example, if the phosphor component has been
applied to or in the shape of fossil leaves, then just this shape
will fluoresce.
Example 8 Prophetic
[0172] The structure from Example 1 can be thermoformed or drape
formed into various shapes during lamination, before cooling or if
reheated to roughly 220-300.degree. F. Higher temperatures may
cause flow of the sheet material and thus deactivate the LEC panel.
One should start at the lower temperatures and can increase
temperature incrementally to decrease pressure and/or lamination
times.
Example 9
[0173] The layup was constructed with 118 mil Spectar copolyester
plastic sheeting, CeeLite LEC panel and 118 mil Spectar copolyester
plastic sheeting. A hand-held mini-extruder with copolyester
welding rod was used to seal the four edges around the perimeter.
Spacers (60 mil.times.0.5''.times.12'' Spectar) were added between
the two sheets to create a gap to be filled by the welding rod. The
edges were then cut and planed for aesthetic purposes.
[0174] SPECTAR.TM. is an amorphous copolyester containing
1,4-cyclohexanedimethanol as a comonomer.
[0175] PROVISTA.TM. is an amorphous copolyester containing
1,4-cyclohexanedimethanol as a comonomer and timellitic anhydride
as a branching agent.
Example 10
[0176] Spectar and Provista were individually laminated at
120.degree. C., 7000 lbs of ram force, for a time of 30 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.3 square inches and
increased to a final area of 147.0 square inches resulting in an
area increase of 2.7 square inches. For Provista, the initial area
was 144.4 square inches and increased to a final area 146.5 square
inches resulting in an area increase of 2.1 square inches.
Example 11
[0177] Spectar and Provista were individually laminated at
120.degree. C., 21000 lbs of ram force, for a time of 30 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 137.6 square inches and
increased to a final area of 142.9 square inches resulting in an
area increase of 5.3 square inches. For Provista, the initial area
was 144.5 square inches and increased to a final area 148.4 square
inches resulting in an area increase of 3.9 square inches.
Example 12
[0178] Spectar and Provista were individually laminated at
120.degree. C., 7000 lbs of ram force, for a time of 90 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.2 square inches and
increased to a final area of 147.0 square inches resulting in an
area increase of 2.8 square inches. For Provista, the initial area
was 144.1 square inches and increased to a final area 146.7 square
inches resulting in an area increase of 2.6 square inches.
Example 13
[0179] Spectar and Provista were individually laminated at
120.degree. C., 21000 lbs of ram force, for a time of 90 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.3 square inches and
increased to a final area of 150.3 square inches resulting in an
area increase of 6.0 square inches. For Provista, the initial area
was 143.2 square inches and increased to a final area 147.7 square
inches resulting in an area increase of 4.5 square inches.
Example 14
[0180] Spectar and Provista were individually laminated at
140.degree. C., 7000 lbs of ram force, for a time of 30 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.4 square inches and
increased to a final area of 160.8 square inches resulting in an
area increase of 16.4 square inches. For Provista, the initial area
was 143.1 square inches and increased to a final area 151.1 square
inches resulting in an area increase of 7.9 square inches.
Example 15
[0181] Spectar and Provista were individually laminated at
140.degree. C., 21000 lbs of ram force, for a time of 30 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.3 square inches and
increased to a final area of 170.8 square inches resulting in an
area increase of 26.5 square inches. For Provista, the initial area
was 144.4 square inches and increased to a final area 161.8 square
inches resulting in an area increase of 17.4 square inches.
Example 16
[0182] Spectar and Provista were individually laminated at
140.degree. C., 16000 lbs of ram force, for a time of 60 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.4 square inches and
increased to a final area of 170.8 square inches resulting in an
area increase of 26.5 square inches. For Provista, the initial area
was 143.4 square inches and increased to a final area 160.1 square
inches resulting in an area increase of 16.7 square inches.
Example 17
[0183] Spectar and Provista were individually laminated at
140.degree. C., 7000 lbs of ram force, for a time of 90 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.2 square inches and
increased to a final area of 165.5 square inches resulting in an
area increase of 21.3 square inches. For Provista, the initial area
was 138.1 square inches and increased to a final area 150.1 square
inches resulting in an area increase of 12.0 square inches.
Example 18
[0184] Spectar and Provista were individually laminated at
140.degree. C., 21000 lbs of ram force, for a time of 90 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 145.2 square inches and
increased to a final area of 180.1 square inches resulting in an
area increase of 34.9 square inches. For Provista, the initial area
was 144.3 square inches and increased to a final area 168.8 square
inches resulting in an area increase of 24.5 square inches.
Example 19
[0185] Spectar and Provista were individually laminated at
160.degree. C., 7000 lbs of ram force, for a time of 30 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.4 square inches and
increased to a final area of 184.6 square inches resulting in an
area increase of 40.1 square inches. For Provista, the initial area
was 143.2 square inches and increased to a final area 166.2 square
inches resulting in an area increase of 22.9 square inches.
Example 20
[0186] Spectar and Provista were individually laminated at
160.degree. C., 21000 lbs of ram force, for a time of 30 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.5 square inches and
increased to a final area of 213.1 square inches resulting in an
area increase of 68.7 square inches. For Provista, the initial area
was 144.3 square inches and increased to a final area 194.7 square
inches resulting in an area increase of 50.4 square inches.
Example 21
[0187] Spectar and Provista were individually laminated at
160.degree. C., 7000 lbs of ram force, for a time of 90 seconds
heating after reaching a temperature within 10.degree. C. of the
setpoint. For Spectar, the initial area was 144.5 square inches and
increased to a final area of 201.4 square inches resulting in an
area increase of 57.0 square inches. For Provista, the initial area
was 143.2 square inches and increased to a final area 177.8 square
inches resulting in an area increase of 34.6 square inches.
Example 22 (Prophetic)
[0188] A UV copolyester film is laminated to the top surface of a
two sheets of polymer and the entire structure is laminated
according to the layup described above and process conditions
described in example 1. The use of a branched polymer resulted in
less flow and less thinning of both the UV film and the sheet
thereby saving cost and waste in material utilization while
maintaining optimum performance. The optimum performance is
maintained because the UV film flows and becomes thinner resulting
in poor weathering as the layer thickness decreased too much to
protect the laminate.
Example 23 (Prophetic)
[0189] A graphics film is an inclusion between two sheets of
polymers and laminated according to the layup described above and
process conditions described in example 1. The use of a branched
polymer resulted in less flow and no distortion to the graphic.
When using non-branched polymers, the polymer flows more and
distorts the graphic.
Example 24 (Prophetic)
[0190] A paper inclusion is inserted between two sheets of polymers
and laminated according to the layup described above and process
conditions described in example 1. When using the branched resins,
the polymers do not flow as much and the paper inclusion does not
tear or distort. When using non branched resins, the paper
inclusion is damaged by the lamination process.
TABLE-US-00001 TABLE 1 Setup Conditions Spectar Provista Ram Final
Final Temp Time Force Pressure Init Area Area .DELTA. Area Pressure
Init Area Area .DELTA. Area Example # (.degree. C.) (seconds) (lbs)
(lbs/in.sup.2) (in.sup.2) (in.sup.2) (in.sup.2) (lbs/in.sup.2)
(in.sup.2) (in.sup.2) (in.sup.2) 1 120 30 7000 48.5 144.3 147.0 2.8
48.5 144.4 146.5 2.2 2 120 30 21000 152.6 144.6 142.9 5.3 145.3
144.5 148.4 3.9 3 120 90 7000 48.6 144.2 147.0 2.8 48.6 144.1 146.7
2.6 4 120 90 21000 145.5 144.3 150.3 6.0 146.7 143.2 147.7 4.5 5
140 30 7000 48.5 144.4 160.8 16.4 48.9 143.1 151.1 7.9 6 140 30
21000 145.5 144.3 170.8 26.5 145.4 144.4 161.8 17.4 7 140 60 14000
97.0 144.4 170.8 26.5 97.6 143.4 160.1 16.7 8 140 90 7000 48.5
144.2 165.5 21.3 50.7 138.1 150.1 12.0 9 140 90 21000 144.6 145.2
180.1 34.9 145.6 144.3 168.8 24.5 10 160 30 7000 48.5 144.4 184.6
40.1 48.9 143.2 166.2 22.9 11 160 30 21000 145.4 144.5 213.1 68.7
145.5 144.3 194.7 50.4 12 160 90 7000 48.5 144.5 201.4 57.0 48.9
143.2 177.8 34.6
[0191] The data show consistently less flow of the laminate sheets
when branched resins are used. This will result in less distortion
of interlayer materials and better retention of hard coated or UV
surface layers. The use of branched polymers whether polyesters,
polycarbonates, blends etc. results in less flow during the
lamination process and better overall dimensional stability. This
improvement leads to a reduction cycle time and reduced material
waste while also protecting appearance and function of inclusions
and functional surface layers.
[0192] This invention can be further illustrated by the following
examples of preferred embodiments thereof, although it will be
understood that these examples are included merely for purposes of
illustration and are not intended to limit the scope of the
invention unless otherwise specifically indicated. The starting
materials are commercially available unless otherwise
indicated.
* * * * *