TWI390478B - Electronic paper display apparatus and manufacturing method thereof - Google Patents

Description

Electronic paper display device and manufacturing method thereof

The present invention relates to a display device and a method of fabricating the same, and more particularly to an electronic paper display device and a method of fabricating the same.

1 is a cross-sectional view showing a conventional electronic paper display device. Referring to FIG. 1 , a conventional electronic paper display device 100 includes a circuit board 110 , an electronic paper display panel 120 disposed on the circuit board 110 , a protective film 130 covering the electronic paper display panel 120 , and an encapsulant 140 . The protective film 130 is larger than the electronic paper display panel 120 in this design, so that the side walls 132 of the protective film 130 extend beyond the side walls 122 of the electronic paper display panel 120. As such, there is a gap G between the protective film 130 and the wiring board 110, and the gap G surrounds the sidewall 122 of the electronic paper display panel 120. The encapsulant 140 is disposed on the circuit board 110 and is used to seal the electronic paper display panel 120.

However, since the gap G is larger than the semi-enclosed space defined by the electronic paper display panel 120 by the protective film 130, when the dispensing operation of the encapsulant 140 is performed, the encapsulant 140 is easily sealed while filling the gap G. The path of the gas discharge is blocked, so that the bubble B exists in the gap G. In other words, the encapsulant 140 does not completely seal the electronic paper display panel 120 and moisture easily invades the electronic paper display panel 120. The electronic paper display device 100 therefore cannot have good quality and long service life.

In addition, the prior art also proposes another electronic paper display device in which the electronic paper display panel is aligned with the edge of the protective film, and the encapsulant thereof is disposed on the circuit board and located on the edge of the electronic paper display panel and the protective film. The electronic paper display device is manufactured by first laminating an uncut entire electronic paper display panel and a last cut protective film into a composite structure, and then cutting the composite structure into a plurality of composite structural units. .

However, the yield of the entire electronic paper display panel that has not been cut is only 70%, and when the electronic paper display panel of the composite structural unit is detected to have a bad point or foreign matter, it needs to be scrapped together with the protective film of the composite structural unit. Therefore, the production cost is high (the cost of the protective film is the same as the cost of the electronic paper display panel).

Furthermore, since the electronic paper display panel of the electronic paper display device is aligned with the edge of the protective film, the package colloid does not easily cover the edges of the electronic paper display panel and the protective film, and the electronic paper display panel and the protective film are easily subjected to external forces. Separated from the encapsulant.

The invention provides an electronic paper display device and a manufacturing method thereof, which can effectively prevent water and gas from invading an electronic paper display panel.

The invention provides an electronic paper display device comprising a substrate, an electronic paper display panel, a protective film and an encapsulant. The electronic paper display panel is disposed on the substrate, and the electronic paper display panel has a display area and a non-display area surrounding the display area. The protective film is disposed on the electronic paper display panel, and the protective film is smaller than the electronic paper display panel such that a first sidewall of the electronic paper display panel is spaced apart from a second sidewall of the protective film to expose at least a portion of the non-display area. The encapsulant is disposed on the substrate, surrounding the electronic paper display panel and the protective film, wherein the encapsulant adheres to the first sidewall and the second sidewall and covers at least a portion of the non-display area exposed by the protective film.

The present invention provides a method of fabricating an electronic paper display device as follows. First, a substrate is provided. Next, an electronic paper display panel is disposed on the substrate, and the electronic paper display panel has a display area and a non-display area surrounding the display area. Then, a protective film is attached to the electronic paper display panel, and the protective film is smaller than the electronic paper display panel such that a first sidewall of the electronic paper display panel and a second sidewall of the protective film are separated by a distance, and at least a portion is exposed. Non-display area. Thereafter, an encapsulant is formed on the substrate to surround the electronic paper display panel and the protective film, wherein the encapsulant adheres to the first sidewall and the second sidewall and covers at least a portion of the non-display area exposed by the protective film.

As described above, since the protective film of the present invention is smaller than the electronic paper display panel, the encapsulant can directly and closely cover the first side wall of the electronic paper display panel, the second side wall of the protective film, and the exposed surface of the protective film. Part of the non-display area. Therefore, the electronic paper display device of the present invention can avoid the generation of air bubbles in the encapsulant, thereby improving the ability of the encapsulant to block moisture.

The above described features and advantages of the present invention will be more apparent from the following description.

2A is a plan view of an electronic paper display device according to an embodiment of the present invention, and FIG. 2B is a cross-sectional view of the electronic paper display device of FIG. 2A taken along line I-I'.

Referring to FIG. 2A and FIG. 2B , the electronic paper display device 200 of the present embodiment includes a substrate 210 , an electronic paper display panel 220 , a protective film 230 , and an encapsulant 240 . The substrate 210 is, for example, an active array substrate, a plastic substrate, a flexible circuit board, a printed circuit board, a stainless steel substrate, or a flexible substrate.

The electronic paper display panel 220 is disposed on the substrate 210. If the substrate 210 has a line (not shown), the electronic paper display panel 220 can be selectively electrically connected to the substrate 210. The electronic paper display panel 220 has a display area 222a and a non-display area 222b surrounding the display area 222a. In the present embodiment, the width W1 of the non-display area 222b is substantially 2 mm.

The protective film 230 is disposed on the electronic paper display panel 220. The protective film 230 is smaller than the electronic paper display panel 220 such that a first sidewall 224 of the electronic paper display panel 220 is separated from a second sidewall 234 of the protective film 230 by a distance D (for example, It is 0.25 mm to 0.5 mm), and at least a portion of the non-display area 222b is exposed. In the present embodiment, FIG. 2B illustrates a case where the protective film 230 exposes a portion of the non-display area 222b. In other embodiments, the protective film 230 may also expose all of the non-display area 222b. The material of the protective film 230 is, for example, polyethylene-terephthalate (PET) or other water vapor-permeable material.

In the present embodiment, the protective film 230 is smaller than the electronic paper display panel 220, and the width W2 of the protective film 230 is smaller than the width W3 of the electronic paper display panel 220 in the same cross section, or the protective film 230 is attached to the electronic paper display panel 220. The area of the combined surface 236 is smaller than the area of the surface 222 of the electronic paper display panel 220 that is bonded to the protective film 230, so that the protective film 230 exposes a portion 222 of the surface of the electronic paper display panel 220.

The first side wall 224 of the electronic paper display panel 220 is spaced apart from the second side wall 234 of the protective film 230 by a distance D, that is, the side walls 224a, 224b, 224c, 224d are separated from the corresponding side walls 234a, 234b, 234c, 234d by a distance D, respectively. In addition, this embodiment is exemplified by a quadrangular protective film 230 and an electronic paper display panel 220, but is not intended to limit the present invention. For example, in other embodiments, the protective film 230 and the electronic paper display panel 220 may be circular, polygonal, or other irregularly shaped structures.

The encapsulant 240 is disposed on the substrate 210 and surrounds the electronic paper display panel 220 and the protective film 230. The material of the encapsulant 240 is, for example, a thermosetting material or a photocurable material. In this embodiment, the encapsulant 240 is in close contact with the first sidewall 224 and the second sidewall 234 and covers a portion of the non-display region 222b exposed by the protective film 230. In detail, the encapsulant 240 has a first stepped structure 242 and a second stepped structure 244. The first stepped structure 242 is in close contact with the first sidewall 224 of the electronic paper display panel 220 and the partial substrate 210, and the second stepped structure 244 is adjacent to the second sidewall 234 of the protective film 230 and the covered electronic paper display panel. 220 is away from surface 222 of substrate 210. It should be noted that, in this embodiment, the orthographic projection of the encapsulant 240 on the electronic paper display panel 220 is located outside the display area 222a to avoid obscuring the image displayed by the display area 222a.

As described above, since the protective film 230 is smaller than the electronic paper display panel 220, the encapsulant 240 can directly cover the first sidewall 224, the second sidewall 234, and the portion exposed by the protective film 230 when the encapsulant 240 is formed. On the non-display area 222b. Therefore, the encapsulant 240 is annularly wrapped around the electronic paper display panel 220 and the protective film 230, and the encapsulation region (the first stepped structure 242 and the second stepped structure 244) is formed into an open structure to avoid blocking gas discharge. The path, in turn, reduces the generation of bubbles while enhancing the ability of the electronic paper display device 200 to resist moisture. Moreover, since the encapsulant 240 covers the substrate 210 and the surface 222 of the electronic paper display panel 220 at the same time, it can help to fix the electronic paper display panel 220 on the substrate 210. That is, the encapsulant 240 and the electronic paper display panel 220 constitute a structure that interferes with each other in the present embodiment to contribute to stably fixing the electronic paper display panel 220. Further, in the electronic paper display panel 220 and the protective film 230, since the sealing area of the encapsulant 240 is large, the bonding strength can be increased, and the external force can be prevented from causing the encapsulation colloid 240 to be cracked.

3A is a plan view of an electronic paper display device according to another embodiment of the present invention, and FIG. 3B is a cross-sectional view of the electronic paper display device of FIG. 3A taken along line II-II'. 3A and 3B, the electronic paper display device 200' is substantially the same as the electronic paper display device 200. However, in this embodiment, the portion of the encapsulant 240' may also extend to the surface 232 of the protective film 230 remote from the electronic paper display panel 220 (as shown in Figures 3A and 3B). For example, the width W4 of the portion of the cover surface 232 of the encapsulant 240 is, for example, 0.2 mm to 0.5 mm. The design of this embodiment is such that the partial encapsulant 240' covers the surface 232 of the protective film 230 to increase the bonding area, and the external gas is prevented from penetrating into the interior of the joint between the encapsulant 240 and the protective film 230.

The method of manufacturing the aforementioned electronic paper display device 200 will be described in detail below.

4A to 4C are cross-sectional views showing processes of an electronic paper display device according to an embodiment of the present invention. First, referring to FIG. 4A, a substrate 210 is provided. Next, an electronic paper display panel 220 is disposed on the substrate 210. The electronic paper display panel 220 has a display area 222a and a non-display area 222b surrounding the display area 222a. At this time, if the substrate 210 has a line (not shown), the electronic paper display panel 220 can be selectively electrically connected to the substrate 210.

Then, referring to FIG. 4B, a protective film 230 is attached to the electronic paper display panel 220. The protective film 230 is smaller than the electronic paper display panel 220 such that a first sidewall 224 of the electronic paper display panel 220 and the protective film 230 are The second side wall 234 is spaced apart by a distance D to expose at least a portion of the non-display area 222b.

Thereafter, referring to FIG. 4C, an encapsulant 240 is formed on the substrate 210, which surrounds the electronic paper display panel 220 and the protective film 230. In detail, the encapsulant 240 is in close contact with the first sidewall 224 and the second sidewall 234 and covers at least a portion of the non-display area 222b exposed by the protective film 230.

In this embodiment, the method of forming the encapsulant 240 may be to apply a flowable colloidal material (not shown) to the substrate 210 in a herringo-type package. Then, the colloidal material is selectively cured by thermal curing, photocuring or other suitable curing methods according to the kind of the colloidal material to form the encapsulant 240, wherein the encapsulant 240 is on the electronic paper display panel 220. The upper orthographic projection may be outside the display area 222a. Since the protective film 230 is smaller than the electronic paper display panel 220, the colloidal material may abut against the first side wall 224 of the electronic paper display panel 220 and the second side wall 234 of the protective film 230. At the same time, the colloidal material also covers a portion of the substrate 210 and a portion of the non-display area 222b that is not covered by the protective film 230. Therefore, the encapsulant 240 of the present embodiment can completely seal the sidewall of the electronic paper display panel 220 to achieve the function of reliably blocking moisture from entering the electronic paper display panel 230.

Moreover, in other embodiments, the method of forming the encapsulant 240 further includes extending the colloidal material to the surface 232 of the protective film 230 remote from the electronic paper display panel 220 to cover a portion of the surface 232 of the protective film 230. As such, after the colloidal material is cured, the encapsulant 240' of Figures 3A and 3B can be formed.

It is to be noted that the electronic paper display panel 220 of the present embodiment is a cut electronic paper display panel, and is disposed on the substrate 210 after no abnormality in Automated Optical Inspection (AOI). The protective film 230 on the electronic paper display panel 220 is not scrapped due to a defective or foreign matter on the electronic paper display panel 220. In this way, the present embodiment can avoid the problem that the manufacturing cost is high due to the scrapped protective film.

In summary, since the protective film of the present invention is smaller than the electronic paper display panel, the encapsulant can directly cover the first sidewall of the electronic paper display panel, the second sidewall of the protective film, and the portion exposed by the protective film. On the display area. In the process of manufacturing the electronic paper display device, the generation of bubbles in the encapsulant can be avoided, thereby improving the water vapor resistance of the encapsulant. Furthermore, since the encapsulant covers both the substrate and the surface of the electronic paper display panel away from the substrate, it helps to fix the electronic paper display panel on the substrate. In addition, with respect to the electronic paper display panel and the protective film, the encapsulating colloid has a large bonding area, so that the bonding strength can be increased, and the external colloid can be prevented from causing the encapsulant to be cracked.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100, 200, 200’. . . Electronic paper display device

110. . . circuit board

120, 220. . . Electronic paper display panel

122, 132, 224a, 224b, 224c, 224d, 234a, 234b, 234c, 234d. . . Side wall

130, 230. . . Protective film

140, 240, 240’. . . Encapsulant

210. . . Substrate

222, 232, 236. . . surface

222a. . . Display area

222b. . . Non-display area

224. . . First side wall

234. . . Second side wall

242. . . First stepped structure

244. . . Second stepped structure

B. . . bubble

D. . . distance

G. . . gap

W1, W2, W3, W4. . . width

1 is a cross-sectional view showing a conventional electronic paper display device.

2A is a top plan view of an electronic paper display device in accordance with an embodiment of the present invention.

Figure 2B is a cross-sectional view of the electronic paper display device of Figure 2A taken along line I-I'.

3A is a top plan view of an electronic paper display device according to another embodiment of the present invention.

Figure 3B is a cross-sectional view of the electronic paper display device of Figure 3A taken along line II-II'.

4A to 4C are cross-sectional views showing processes of an electronic paper display device according to an embodiment of the present invention.

200. . . Electronic paper display device

210. . . Substrate

220. . . Electronic paper display panel

222, 232, 236. . . surface

222a. . . Display area

222b. . . Non-display area

224. . . First side wall

230. . . Protective film

234. . . Second side wall

240. . . Encapsulant

242. . . First stepped structure

244. . . Second stepped structure

D. . . distance

W1, W2, W3. . . width

Claims (8)

An electronic paper display device comprising: a substrate; an electronic paper display panel disposed on the substrate, the electronic paper display panel having a display area and a non-display area surrounding the display area; a protective film disposed on the The electronic paper display panel is smaller than the electronic paper display panel such that a first sidewall of the electronic paper display panel is spaced apart from a second sidewall of the protective film to expose at least a portion of the non-display area; An encapsulant disposed on the substrate to surround the electronic paper display panel and the protective film, wherein the encapsulant adheres to the first sidewall and the second sidewall and covers at least a portion exposed by the protective film The non-display area. The electronic paper display device of claim 1, wherein a portion of the encapsulant further covers a portion of the surface of the protective film away from the electronic paper display panel. The electronic paper display device of claim 1, wherein the material of the encapsulant comprises a thermosetting material or a photocurable material. The electronic paper display device of claim 1, wherein the protective film comprises polyethylene-terephthalate (PET). A method for manufacturing an electronic paper display device, comprising: providing a substrate; and arranging an electronic paper display panel on the substrate, the electronic paper display panel having a display area and a non-display area surrounding the display area; The film is attached to the electronic paper display panel, the protective film is smaller than the electronic paper display panel such that a first sidewall of the electronic paper display panel and a second sidewall of the protective film are separated by a distance to expose at least a portion Forming a non-display area; and forming an encapsulant on the substrate, surrounding the electronic paper display panel and the protective film, wherein the encapsulant adheres to the first sidewall and the second sidewall and covers the exposed surface of the protective film At least part of the non-display area. The method for fabricating an electronic paper display device according to claim 5, wherein the method for forming the encapsulant comprises: forming a flowable gel material on the substrate, and the gel material is closely attached to the electronic paper. The first side wall of the panel and the second side wall of the protective film and the colloid material cover a portion of the substrate and a portion of the non-display area not covered by the protective film; and curing the colloidal material. The method for fabricating an electronic paper display device according to claim 6, wherein the method for forming the encapsulant further comprises covering the surface of the protective film away from the electronic paper display panel. The method for fabricating an electronic paper display device according to claim 6, wherein the method of curing the colloidal material comprises a thermal curing method or a photo curing method.