U.S. patent application number 13/718857 was filed with the patent office on 2013-10-17 for transfer film for attaching protection film to flat panel display and method for manufacturing the flat panel display using the same.
This patent application is currently assigned to LG DISPLAY CO., LTD.. The applicant listed for this patent is LG DISPLAY CO., LTD.. Invention is credited to Jongmoo KIM, Chanwoo LEE.
Application Number | 20130273292 13/718857 |
Document ID | / |
Family ID | 49325353 |
Filed Date | 2013-10-17 |
United States Patent
Application |
20130273292 |
Kind Code |
A1 |
KIM; Jongmoo ; et
al. |
October 17, 2013 |
TRANSFER FILM FOR ATTACHING PROTECTION FILM TO FLAT PANEL DISPLAY
AND METHOD FOR MANUFACTURING THE FLAT PANEL DISPLAY USING THE
SAME
Abstract
The present disclosure relates to a transfer film for attaching
protection film to flat panel display and method for manufacturing
the flat panel display using the same. The present disclosure
suggests a transfer film comprising: a lower film; and a protection
film temporarily attached on the lower film and including a base
film and an adhesion layer disposed on an upper surface of the base
film. In the present disclosure, the flat panel display can be
encapsulated using a transfer film having a protection film
temporarily attached on a flexible lower film, so that it is
possible to perfectly encapsulate the flat panel display with the
protection film without any foreign material such as air
bubble.
Inventors: |
KIM; Jongmoo; (Seoul,
KR) ; LEE; Chanwoo; (Paju-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG DISPLAY CO., LTD. |
Seoul |
|
KR |
|
|
Assignee: |
LG DISPLAY CO., LTD.
Seoul
KR
|
Family ID: |
49325353 |
Appl. No.: |
13/718857 |
Filed: |
December 18, 2012 |
Current U.S.
Class: |
428/40.1 ;
156/230; 156/235; 428/195.1; 428/212; 428/354 |
Current CPC
Class: |
Y10T 428/14 20150115;
B32B 3/30 20130101; B32B 7/06 20130101; B32B 37/18 20130101; B32B
38/10 20130101; Y10T 428/2848 20150115; Y10T 428/24802 20150115;
Y10T 428/24942 20150115; B32B 37/025 20130101; B32B 2457/20
20130101; G02F 1/13 20130101; H01L 51/5253 20130101 |
Class at
Publication: |
428/40.1 ;
428/354; 428/212; 428/195.1; 156/230; 156/235 |
International
Class: |
B32B 7/06 20060101
B32B007/06; B32B 37/00 20060101 B32B037/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 16, 2012 |
KR |
10-2012-0039234 |
Claims
1. A transfer film for attaching a film of a flat panel display,
the transfer film comprising: a lower film; and a protection film
temporarily attached on the lower film and including a base film
and an adhesion layer disposed on an upper surface of the base
film.
2. The transfer film according to claim 1, wherein the protection
film further includes a relief film attached on an upper surface of
the adhesion layer, and wherein the transfer film further comprises
an upper film including a flexible relief base facing the relief
film of the protection film and a strong adhesion layer disposed on
a surface of the flexible relief base configured to attach with the
relief film.
3. The transfer film according to claim 1, wherein the lower film
includes: a flexible transfer base; and a weak adhesion layer
disposed on a surface of the flexible transfer base configured to
attach with the base film of the lower film.
4. The transfer film according to claim 1, wherein the protection
film is temporarily attached on the lower film in a manner that a
plurality of unit protection films is disposed in a matrix
array.
5. The transfer film according to claim 4, wherein the each unit
protection film comprises a unit upper film including: a unit
flexible relief base facing the relief film of the each unit
protection film; and a unit strong adhesion layer disposed on a
surface of the unit flexible relief base configured to attach with
the relief film.
6. A manufacturing method of a flat panel display, the method
comprising: forming a display panel; forming a transfer film
including a protection film having a lower film, a base film
temporarily attached on the lower film, and an adhesion layer
disposed on an upper surface of the base film; attaching the
transfer film on an upper surface of the display panel by adhering
the protection film on the display panel; and removing the lower
film of the transfer film to encapsulate the display panel by the
protection film.
7. The method according to claim 6, wherein the forming the
transfer film includes: preparing the lower film having a flexible
transfer base and a weak adhesion layer disposed on one side of the
flexible transfer base; preparing the protection film having the
base film, the adhesion layer disposed on the upper surface of the
base film, and a relief film disposed on the adhesion layer;
preparing an upper film having a flexible relief base and a strong
adhesion layer disposed on one surface of the flexible relief base;
temporarily attaching the base film of the protection film on the
weak adhesion layer of the lower film; adhering the strong adhesion
layer of the upper film on the relief film of the protection film;
selectively patterning the upper film and the protection film to
have same size corresponding to the display panel; and removing the
upper film to peel off the relief film of the protection film.
8. The method according to claim 6, wherein the attaching the
transfer film on the upper surface of the display panel is
conducted from one end side to the other end side by a roller.
9. The method according to claim 6, further comprising: attaching a
circular polarization film on the protection film; and attaching a
cover film on the display panel having the circular polarization
film with an optical adhesive.
10. The method according to claim 9, wherein the forming the
display panel includes: depositing a sacrifice layer on a rigid
substrate; depositing a flexible layer on the rigid substrate; and
forming display elements on the flexible layer, and wherein, after
attaching the cover film, the method further comprises: separating
the flexible layer from the rigid substrate by removing the
sacrifice layer; attaching a back panel at a rear surface of the
flexible layer.
Description
[0001] This application claims the benefit of Korean Patent
Application No. 10-2012-0039234 filed on Apr. 16, 2012, which is
incorporated herein by reference for all purposes as if fully set
forth herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present disclosure relates to a transfer film for
attaching protection film to flat panel display and method for
manufacturing the flat panel display using the same. Especially,
the present disclosure relates to a transfer film having protection
films temporarily to prevent an organic light emitting diode
display device (OLED) from moisture and a method for manufacturing
the OLED using the same.
[0004] 2. Discussion of the Related Art
[0005] Nowadays, various flat panel display devices are developed
for overcoming many drawbacks of the cathode ray tube such as heavy
weight and bulk volume. The flat panel display devices include the
liquid crystal display device (or LCD), the field emission display
(or FED), the plasma display panel (or PDP) and the
electroluminescence display device (or ED).
[0006] The electroluminescence display device is categorized in the
inorganic light emitting diode display device and the organic light
emitting diode display device according to the luminescence
material. As a self-emitting display device, the
electroluminescence display device has the merits those the
response speed is very fast, the brightness is very high and the
view angle is large. FIG. 1 illustrates the structure of the
organic light emitting diode according to the related art.
Referring to FIG. 1, the organic light emitting diode comprises the
organic light emitting material layer, and the cathode and the
anode which are facing each other with the organic light emitting
material layer therebetween. The organic light emitting material
layer comprises the hole injection layer HIL, the hole transport
layer HTL, the emission layer EML, the electron transport layer ETL
and the electron injection layer EIL.
[0007] The organic light emitting diode radiates the lights due to
the energy from the excition formed at the excitation state in
which the hole and the electron are recombined at the emission
layer EML. The organic light emitting display device represents the
video data by controlling the light brightness from the emission
layer EML of the organic light emitting diode.
[0008] The organic light emitting diode display (or OLED) using the
organic light emitting diode can be categorized in the passive
matrix type organic light emitting diode display (or PMOLED) and
the active matrix type organic light emitting diode display (or
AMOLED). Furthermore, according to the direction of the emitted
light, it can be categorized in the top emission type and the
bottom emission type.
[0009] By representing any video/image in the natural color, the
organic light emitting diode display is currently coming into the
lime light, and widely applied in various field including the
portable personal information devices such as cellular phone, smart
phone or PDAs. The OLED is the self luminescence display having the
high responding speed less than lms and the low power consumption,
for representing natural full color images/videos. Furthermore, it
has wide view angle covering near 180 degree, and it is best device
for display regardless of diagonal size. Its manufacturing method
is very simple, based on the low temperature process and the
conventional semiconductor processing technologies.
[0010] However, the OLED is very weak from oxygen and moisture. In
order to ensure the reliability of the OLED property, until now,
the glass substrate having a getter is used for encapsulation of
the organic light emitting material. As the requirement and needs
for the thin and flexible display are increased, the glass
substrate may be exchanged by film type encapsulation as the
protecting film for the OLED panel.
[0011] Hereinafter, referring to FIGS. 2A and 2B, we will explain
how to attaching the protection film to the OLED according to the
related art. FIGS. 2A and 2B are perspective views illustrating the
processes for attaching the protection film to the organic light
emitting diode display panel.
[0012] As shown in FIG. 2A, in the related art, after placing the
protection film FF on the transferring substrate PT at each pattern
using a metal jig MM, the protection film FF is transferred to the
organic light emitting diode display panel.
[0013] In order to maintain the shape, the metal jig MM is made of
rigid metal material. The metal jig MM has a plurality of pattern
hole HO at which each protection film FF is located. As well known
to ordinary skilled person, a plurality of the OLED panels are
arrayed in a matrix pattern, on one large mother substrate MG, each
protection film FF is attached on each organic light emitting diode
display panel, and then a plurality of the unit OLED displays are
completed by cutting the mother substrate MG.
[0014] The metal jig MM is combined with the transferring substrate
PT. Each protection film FF is located at each pattern hole HO
formed at the metal jig MM. At this time, the protection film FF is
located as the adhesive surface is facing upward. The adhesive may
be the thermal hardening epoxy resin.
[0015] Referring to FIG. 2B, a mother substrate MG having a
plurality of organic light emitting diode display panels OLED is
located on the metal jig MM. By aligning each organic light
emitting diode display panel OLED with each protection film FF
relatively, the mother substrate MG is placed on the metal jig MM.
After that, keeping the chamber temperature to 70.degree. C. to
melt the adhesive, the protection films FF are attached on the
organic light emitting diode display panels OLED. At the same time,
keeping the chamber in vacuum condition, the protection films FF
and the organic light emitting diode display panels OLED should be
firmly closed to each other. After that, increasing the temperature
of the chamber up to 100.degree. C. for hardening the adhesive, the
protection films FF are permanently attached on the organic light
emitting diode display panels OLED.
[0016] Like this, as the method for attaching the protection film
to the organic light emitting diode display panel OLED according to
the related art is conducted under vacuum condition, the vacuum
facility is required. Furthermore, for hardening the adhesive, the
oven system is also required. Especially, aligning the substrate
with the metal jig and conducting processes in oven and vacuum
chamber through a manual processes, the method according to the
related art is not proper to apply In-line type facility for mass
production. That is, the related art cannot ensure enough yields
for establishing the mass production system.
[0017] In addition, as the protection film is attached to the
organic light emitting diode display panel under vacuum condition,
when the air is not perfectly out, air bubble may be formed so that
the protection film may not be attached correctly. Especially, as
the rigid large substrate should be attached to the transferring
substrate having rigid structure, it is hard to completely
eliminate the air bubble between them so that the final product may
have defects on representing images/videos.
SUMMARY OF THE INVENTION
[0018] In order to overcome the above mentioned drawbacks, the
purpose of the present disclosure is to suggest a transfer film for
attaching a protection film to a flat panel display and a method
for manufacturing a flat panel display using the same transfer
film. Another purpose of the present disclosure is to a transfer
film applied to a In-Line type facility for attaching the transfer
film to a flat panel display without air bubble there-between and a
method for manufacturing a flat panel display using the same
transfer film.
[0019] In order to accomplish the above purpose, the present
disclosure suggests a transfer film comprising: a lower film; and a
protection film temporarily attached on the lower film and
including a base film and an adhesion layer disposed on an upper
surface of the base film.
[0020] The protection film further includes a relief film attached
on an upper surface of the adhesion layer, and further comprising
an upper film including a flexible relief base facing the relief
film of the protection film and a strong adhesion layer disposed on
a surface of the flexible relief base configured to attach with the
relief film.
[0021] The lower film includes: a flexible transfer base; and a
weak adhesion layer disposed on a surface of the flexible transfer
base configured to attach with the base film of the lower film.
[0022] The protection film is temporarily attached on the lower
film in a manner that a plurality of unit protection films is
disposed in a matrix array.
[0023] The each unit protection film comprises a unit upper film
including: a unit flexible relief base facing the relief film of
the each unit protection film; and a unit strong adhesion layer
disposed on a surface of the unit flexible relief base configured
to attach with the relief film.
[0024] Furthermore, the present disclosure suggests a method for
manufacturing a flat panel comprising: forming a display panel;
forming a transfer film including a protection film having a lower
film, a base film temporarily attached on the lower film, and an
adhesion layer disposed on an upper surface of the base film;
attaching the transfer film on an upper surface of the display
panel by adhering the protection film on the display panel; and
removing the lower film of the transfer film to encapsulate the
display panel by the protection film.
[0025] The forming the transfer film includes: preparing the lower
film having a flexible transfer base and a weak adhesion layer
disposed on one side of the flexible transfer base; preparing the
protection film having the base film, the adhesion layer disposed
on the upper surface of the base film, and a relief film disposed
on the adhesion layer; preparing an upper film having a flexible
relief base and a strong adhesion layer disposed on one surface of
the flexible relief base; temporarily attaching the base film of
the protection film on the weak adhesion layer of the lower film;
adhering the strong adhesion layer of the upper film on the relief
film of the protection film; selectively patterning the upper film
and the protection film to have same size corresponding to the
display panel; and removing the upper film to peel off the relief
film of the protection film.
[0026] The attaching the transfer film on the upper surface of the
display panel is conducted from one end side to the other end side
by a roller.
[0027] The method further comprising: attaching a circular
polarization film on the protection film; and attaching a cover
film on the display panel having the circular polarization film
with an optical adhesive.
[0028] The forming the display panel includes: depositing a
sacrifice layer on a rigid substrate; depositing a flexible layer
on the rigid substrate; and forming display elements on the
flexible layer, and wherein the method, after attaching the cover
film, further comprises: separating the flexible layer from the
rigid substrate by removing the sacrifice layer; and attaching a
back panel at a rear surface of the flexible layer.
[0029] In the present disclosure, the flat panel display can be
encapsulated using a transfer film having a protection film
temporarily attached on a flexible lower film. Like this, as a
flexible transfer film is used, it is possible to perfectly
encapsulate the flat panel display with the protection film without
any foreign material such as air bubble. Therefore, the present
disclosure can suggest a method for manufacturing a flat panel
display in which the encapsulating property is enhanced and the
display property is progressed. Further, by preparing the transfer
film with low price materials, the price for manufacturing the flat
panel display can be reduced and the processes can be
simplified.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention.
[0031] In the drawings:
[0032] FIG. 1 illustrates the structure of the organic light
emitting diode according to the related art.
[0033] FIGS. 2A and 2B are perspective views illustrating the
processes for attaching the protection film to the organic light
emitting diode display panel.
[0034] FIGS. 3A to 3D are cross-sectional views illustrating a
method for manufacturing a transfer film configured to attach a
protection film to an organic light emitting diode display panel,
according to the present disclosure.
[0035] FIGS. 4A to 4E are cross-sectional views illustrating the
method for attaching the protection film and method for
manufacturing a flat panel display using the transfer film for
attaching the protection film of the flat panel display according
to the present disclosure.
[0036] FIG. 5 is a perspective view illustrating that four
protection films (#1 to #4) are disposed in a matrix pattern on one
large lower film.
[0037] FIG. 6 is a perspective view illustrating that four organic
light emitting diode display panels (#1 to #4) are disposed on one
large rigid mother substrate.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
[0038] Referring to attached figures, we will explain preferred
embodiments of the present disclosure. Like reference numerals
designate like elements throughout the detailed description.
However, the present disclosure is not restricted by these
embodiments but can be applied to various changes or modifications
without changing the technical spirit. In the following
embodiments, the names of the elements are selected by considering
the easiness for explanation so that they may be different from
actual names.
[0039] Hereinafter, referring to FIGS. 3A to 3D, we will explain
about a transfer film for temporarily attaching a protection film
of a flat display panel according to the present disclosure. FIGS.
3A to 3D are cross-sectional views illustrating a method for
manufacturing a transfer film configured to attach a protection
film to an organic light emitting diode display panel, according to
the present disclosure.
[0040] At first, referring to FIG. 3A, a transfer film for
attaching a protection film of a flat display panel according to
the present disclosure comprises a protection film FF, a lower film
LF, and an upper film UF. The protection film FF includes a base
film BF, an adhesion layer ADH deposited on the whole surface of
one side of the base film BF, and a relief film RF temporarily
stick onto the adhesion layer ADH. The lower film LF includes a
transfer base PE1, and a weak adhesion layer LAH deposited on the
whole surface of one side of the transfer base PE1. And, the upper
film UF includes, a relief base PE2, and a strong adhesion layer
HAH deposited on the whole surface of one side of the relief base
PE2.
[0041] Referring to FIG. 3B, the rear side of the base film BF of
the protection film FF which does not have the adhesion layer ADH
is attached with the weak adhesion layer LAH of the lower film LF.
Further, the relief film RF of the protection film FF is attached
to the strong adhesion layer HAH of the upper film UF. Along to the
cutting line CUT, the upper film UF and the protection film FF are
selectively cut off. In order to cut the upper film UF and the
protection film FF selectively in the multi layer stacked structure
of the lower film LF, the protection film FF and the upper film UP,
it is preferable to use the Thomson Platen Die Cutting method. As a
result, the remained part of the upper film UF and the protection
film FF after cutting off may be same size with the attaching area
on the organic light emitting diode display panel OLED.
[0042] As a result, the transfer film is formed as shown in FIG.
3C. In this condition, the upper film UF is not yet removed from
the transfer film, so that the relief film RF is still attached on
the protection film FF. As the transfer film and the organic light
emitting diode display panel are prepared respectively, until the
protection film FF is attached on the display panel, the upper film
UF should be attached on the transfer film to protect the adhesion
layer ADH from being contaminating by ambient materials. The size
of each protection film FF should be same with the size of each
organic light emitting diode display panel.
[0043] Referring to FIG. 3D, just before attaching the protection
film FF to the organic light emitting diode display panel, the
upper film UF should be removed. At this time, the relief film RF
is also removed (peeled off) because it is firmly adhered to the
upper film UF by the strong adhesion layer HAH. That is, the
adhesive strength of the strong adhesion layer HAH should be
stronger than the adhesive strength of the relief film RF on the
adhesion layer ADH of the protection film FF to remove the relief
film RF simultaneously when removing the upper film UF. In the
interim, the adhesive strength of the weak adhesion layer LAH
temporarily attaching the base film BF of the protection film FF to
the lower film PE1 should be stronger than the adhesive strength of
the relief film RF temporarily attached to the adhesion layer ADH
of the protection film FF, so that the protection film FF cannot be
detached from the lower film LF by the force of removing the relief
film RF.
[0044] The strong adhesion layer HAH should be removed with the
relief film RF when the upper film PE1 is removed, so it should
have strong adhesive strength. On the contrary, the weak adhesion
layer LAH should have strong adhesive strength enough not to detach
the base film BF of the protection film FF from the lower film LF
when the relief film RF is removed. In addition, the lower film LF
should be removed after transferring the protection film FF to the
organic light emitting diode display panel, so that the weak
adhesion layer LAH should have weaker adhesive strength than the
adhesive strength of the adhesion layer ADH after the thermal
hardening process.
[0045] Hereinafter, referring to FIGS. 4A to 4E, we will explain a
method for manufacturing the organic light emitting diode display
by attaching the protection film to the organic light emitting
diode display panel, using the transfer film for attaching the
protection film of the flat display panel as shown in FIG. 3D
according to the present disclosure. FIGS. 4A to 4E are
cross-sectional views illustrating the method for attaching the
protection film and method for manufacturing a flat panel display
using the transfer film for attaching the protection film of the
flat panel display according to the present disclosure.
[0046] At first, referring to FIG. 4A, we will explain about the
process for preparing an organic light emitting diode display
panel. The organic light emitting diode display panel comprises a
plurality of pixel electrode arrayed in a matrix pattern on a
substrate, a thin film transistor disposed at one corner of each
pixel electrode for driving the pixel electrode, and an organic
light emitting diode stacked on the pixel electrode.
[0047] A base substrate GS having enough strength is prepared.
Here, the enough strength means that the base substrate GS is not
bent, distorted or/and deformed to maintain the flatness so that
the elements formed on the base substrate GS are not affected
during the manufacturing processes including loading and unloading
processes between the various facilities and the depositing
process.
[0048] A sacrifice layer SL is deposited on the whole surface of
the base substrate GS. The sacrifice layer SL is a temporarily
layer for dividing the element layer from the base substrate GS for
completing a flexible display. The sacrifice layer SL may include
amorphous silicon. Radiating the laser beam to crystallizing the
amorphous silicon, the base substrate GS can be removed from the
element layers formed thereon.
[0049] On the sacrifice layer SL, a flexible layer FL used for a
flexible substrate of the flexible display is deposited. The
flexible layer FL may include organic materials such as the
polyimide. On the flexible layer FL, a display element layer TL is
formed. The display element layer TL includes a display area for
representing the images/videos and a pad area extending from the
display area. For example, the display element layer TL may be
include a plurality of thin film transistors and pixel areas
disposed in a matrix manner, and an organic light emitting diode
driven by the thin film transistor at each pixel area.
[0050] On the display element layer TL, a passivation layer PAS is
deposited to protect the display element from the out-gas and
moisture. The display element layer TL is formed within some area
of the flexible layer FL. In FIG. 4A, the display element layer TL
is expanded to the right end side. This end portions (pad area) may
include the pads and link lines extended from the display elements.
Therefore, the display elements of the display element layer TL are
covered by the passivation layer PAS, but the pad area is exposed.
Like this, on the exposed pad area of one side (right side) of the
display panel, a film type printed circuit board (COF) having
driver ICs for driving the display elements is disposed, as shown
in FIG. 4A.
[0051] The organic light emitting diode display panel is prepared.
After further comprising a protection element and an optical
element on the organic light emitting diode display panel, the
final organic light emitting diode display can be completed.
[0052] For example, in order to reinforce the protection property
and strength of the passivation layer PAS, a barrier film BF may
cover the display element layer TL over the passivation layer PAS
to encapsulate the display elements. As shown in FIG. 4B, turning
over the transfer film in which the protection film FF is attached
on the lower film LF as shown in FIG. 3D, the adhesion layer ADH of
the protection film FF is attached on the passivation layer PAS of
the organic light emitting diode display panel. At this time, in
order to prevent any air bubble from occurring between the
protection film FF and the passivation layer PAS, one end side of
the protection film FF is firstly contacted one end side of the
passivation layer PAS, after that using a roller ROL, the other
parts of the protection film FF is completely attached by rolling
and pressing to the other end side of the roller ROL. The transfer
film according to the present disclosure has the protection film FF
temporarily attached on the flexible lower film LF, so that it is
possible to attach to the organic light emitting diode display
panel using the roller ROL.
[0053] After the transfer film having the protection film FF
temporarily attached to the lower film LF is joined on the
passivation layer PAS by attaching the protection film FF, by
thermal treatment, the adhesion layer ADH permanently combines the
protection film FF with the passivation layer PAS. For example,
when the adhesion layer ADH includes a thermal hardening adhesive
material, by thermally hardening the adhesion layer ADH in the
thermal treating chamber with 100.degree. C. and more, the
protection film FF can be firmly and permanently adhered to the
passivation layer PAS. After the adhesion layer ADH is hardened
completely, the lower film LF and the weak adhesion layer LAH is
removed from the base film BF of the protection film FF. As a
result, as shown in FIG. 4C, the protection film FF can encapsulate
the passivation layer PAS over the organic light emitting diode
display panel.
[0054] After that, as shown in FIG. 4D, a circular polarization
film CP is attached on the protection film FF. At this time, the
circular polarization film CP should be disposed as covering the
display element area radiating the light for representing
image/video. To complete the organic light emitting diode display,
a cover film CF is attached on the circular polarization film CP.
When attaching the cover film CF, the flatness should be
maintained. Therefore, it is preferable to use an organic optical
adhesion layer AH having excellent flatness and optical properties
for attaching the cover film CF covering the whole surface of the
base substrate GS. More detail, in the present disclosure, the
light emitting direction is the upper side where the circular
polarization film CF is attached. Therefore, the organic optical
adhesion layer AH should be optically transparent material and an
organic material for keeping the flatness of the surface of the
display panel. In addition, the organic optical adhesion layer AH
preferably includes a optical bond material for hardening by the
ultraviolet light. For example, the organic optical adhesion layer
AH may include acrylate esters, acrylate urethanes, mercaptons, and
photoinitiator materials.
[0055] Completing the display after attaching the cover film CF,
this display panel still has the base substrate GS, the rigid
substrate, so it is a non-flexible display. A laser having 532 nm
wavelength is radiated into the sacrifice layer SL from the outside
of the base substrate GS. Especially, the laser beam should be
uniformly radiated and scanned over the whole surface of the
sacrifice layer SL. As a result, the amorphous silicon of the
sacrifice layer SL is changed (i.e. crystallized) so that the base
substrate GS can be departed or separated from the flexible film
FL.
[0056] Further, as shown in 4E, a back panel BP having sufficient
flexibility is attached on the flexible layer FL to complete the
flexible organic light emitting diode display. The back panel BP
may have much thicker thickness than that of the flexible layer FL
to protect the flexible layer FL and other elements formed on the
flexible layer FL, but it has enough thin thickness to maintain the
flexibility of the display.
[0057] On the contrary, when the back panel BP is a rigid substrate
but thin thickness, non-flexible organic light emitting diode
display can be manufactured. Furthermore, when the back panel BP
has much thinner thickness than the base substrate GS, non-flexible
but ultra thin organic light emitting diode display can be
manufactured.
[0058] The above mentioned preferred embodiment of the present
disclosure is the explanation for the manufacturing process of
single organic light emitting diode display by attaching a
protection film to single organic light emitting diode display
panel. In the interim, by forming a plurality of organic light
emitting diode display panels on one mother board and attaching a
plurality of protection films on one large lower film, each
protection film can be attached on each organic light emitting
diode display panel, respectively. In this case, removing the large
lower film, conducting additional processes on the organic light
emitting diode display panels, and then dividing each organic light
emitting diode display panels, a plurality of organic light
emitting diode displays can be completed.
[0059] Hereinafter, referring to FIGS. 5 and 6, we will explain
about a method for attaching the protection film using a large area
transfer film after a plurality of organic light emitting diode
display panels on one large mother rigid substrate. FIG. 5 is a
perspective view illustrating that four protection films (#1 to #4)
are disposed in a matrix pattern on one large lower film. In this
case, as shown in FIG. 3B, after stacking the protection film FF
and an upper film UF on the large area lower film LLF, and cutting
the upper film UF and the protection film FF, the four protection
films (#1 to #4) are disposed as shown in FIG. 5.
[0060] Further, FIG. 6 is a perspective view illustrating that four
organic light emitting diode display panels (#1 to #4) are disposed
on one large rigid mother substrate LGS. The single organic light
emitting diode display panel OLED comprises a display element layer
TL and a film type printed circuit board COF disposed at one side
of the display element layer TL.
[0061] Turning over the transfer film having #1 to #4 protection
films FF disposed on the large area lower film LLF as shown in FIG.
5, placing the protection films FF on the #1 to #4 display element
layers TL, respectively, and pressing and attaching them, the large
area lower film LLF is removed. After that, each protection film FF
can be attached on each organic light emitting diode display panel
disposed on one large mother substrate LGS, and other post
processes, if required, are conducted, then flexible or
non-flexible organic light emitting diode display can be
completed.
[0062] While the embodiment of the present invention has been
described in detail with reference to the drawings, it will be
understood by those skilled in the art that the invention can be
implemented in other specific forms without changing the technical
spirit or essential features of the invention. Therefore, it should
be noted that the forgoing embodiments are merely illustrative in
all aspects and are not to be construed as limiting the invention.
The scope of the invention is defined by the appended claims rather
than the detailed description of the invention. All changes or
modifications or their equivalents made within the meanings and
scope of the claims should be construed as falling within the scope
of the invention.
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