1. Large-size display screen laminating process, its characterized in that includes:

laminating an optical adhesive film between the first panel and the second panel to form a body to be cured;

carrying out vacuum hot pressing on the body to be solidified;

removing the pressure, and carrying out heat treatment on the body to be solidified;

and curing the body to be cured.

2. The process of claim 1, wherein the body to be solidified is defoamed after vacuum hot pressing and before heat treatment.

3. The large-size display screen attaching process according to claim 1, wherein the combination method of the body to be cured is as follows:

tearing off the release film on the first side of the optical adhesive film, and attaching the optical adhesive film to the first panel;

and tearing off the release film on the second side of the optical adhesive film, and attaching the first panel to the second panel.

4. The large-size display screen attaching process according to claim 2, wherein before the release film on the second side of the optical adhesive film is torn off, the optical adhesive film is subjected to ultraviolet irradiation.

5. The large-size display screen attaching process according to claim 1, wherein in the vacuum hot-pressing step, the first panel is closely attached to the second panel.

6. The large-size display screen attaching process according to claim 1, wherein the vacuum hot-pressing step and the continuous heating step are performed in a vacuum hot-pressing apparatus.

7. The large-size display screen attaching process according to claim 1, wherein after the vacuum hot-pressing step, the body to be cured is continuously heated and conveyed.

8. The large-size display screen bonding process according to claim 6 or 7, wherein the continuous heating step is performed in an atmospheric environment.

9. The large-size display screen attaching process according to claim 1, wherein the body to be cured is inspected after the pressure defoaming step is completed.

10. The large-size display screen attaching process according to claim 1, wherein the curing step adopts ultraviolet curing and/or thermal curing.

Background

The full-lamination display screen is small in thickness and high in light transmittance, reflection and dust feeding phenomena can be reduced, the full-lamination process is widely applied to lamination of display screens with different sizes and different application scenes, in the related technology, in the full-lamination process of a large-size or ultra-large-size display screen, stress exists inside a laminated panel after hot pressing, warping and deformation easily occur after the display screen is laminated, and the lamination yield of the display screen is influenced.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a large-size display screen laminating process which can improve the laminating yield of the display screen.

According to the large-size display screen laminating process provided by the embodiment of the invention, an optical adhesive film is laminated between a first panel and a second panel to form a body to be solidified; carrying out vacuum hot pressing on the body to be solidified; removing the pressure, and continuously heating the body to be solidified; and carrying out pressure defoaming and curing on the body to be cured.

The large-size display screen laminating process provided by the embodiment of the invention at least has the following beneficial effects:

in the large-size display screen attaching process in the embodiment of the invention, only the attaching tightness between the first panel and the second panel is properly improved during vacuum hot pressing, so that a primary bonding force is formed between the first panel and the second panel, after pressure is removed, in the process of continuously heating the first panel and/or the second panel, the first panel and the second panel release stress and recover freely, simultaneously, the optical adhesive film is gradually converted into a molten state, the optical adhesive flows freely between the first panel and the second panel and gradually fills a gap between the first panel and the second panel, so that the optical adhesive is filled between the two panels, therefore, in the continuous heating process, on one hand, the stress release of the first panel and the second panel is realized, the panels are prevented from warping and deforming in subsequent steps, on the other hand, the optical adhesive can be fully filled between the two panels, and the attaching smoothness of the first panel and the second panel is improved, thereby improving the bonding quality of the large-size display screen.

According to some embodiments of the present invention, the body to be cured is deaerated after the vacuum hot pressing and before the heat treatment.

According to some embodiments of the invention, the method of assembling the body to be cured is:

tearing off the release film on the first side of the optical adhesive film, and attaching the optical adhesive film to the first panel;

and tearing off the release film on the second side of the optical adhesive film, and attaching the first panel to the second panel.

According to some embodiments of the present invention, before the release film on the second side of the optical adhesive film is peeled off, the optical adhesive film is subjected to ultraviolet irradiation.

According to some embodiments of the invention, the first panel is in close proximity to the second panel during the vacuum hot pressing step.

According to some embodiments of the invention, the vacuum hot-pressing step and the continuous heating step are performed in a vacuum hot-pressing apparatus.

According to some embodiments of the invention, after the vacuum hot-pressing step, the body to be cured is continuously heated and conveyed.

According to some embodiments of the invention, the continuous heating step is performed in an atmospheric environment.

According to some embodiments of the present invention, the body to be cured is inspected after the pressure defoaming step is completed.

According to some embodiments of the invention, the curing step employs uv curing and/or thermal curing.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The invention is further described with reference to the following figures and examples, in which:

FIG. 1 is a schematic flow chart of an embodiment of a large-sized display screen bonding process according to the present invention;

fig. 2 is a schematic flow chart of another embodiment of the large-size display screen attaching process according to the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, the meaning of a plurality is one or more, the meaning of a plurality is two or more, and the above, below, exceeding, etc. are understood as excluding the present numbers, and the above, below, within, etc. are understood as including the present numbers. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

In the description of the present invention, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Referring to fig. 1, in an embodiment of the present invention, a large-sized display screen attaching process is provided, including the following steps: laminating an optical adhesive film between the first panel and the second panel to form a body to be cured; then, carrying out vacuum hot pressing on the body to be solidified so as to consolidate the relative position relationship between the body to be solidified and the body to be solidified when the body to be solidified and the body to be solidified are mutually attached, so that a certain adhesive force is formed between the first panel and the second panel, and the attaching tightness of the first panel and the second panel is improved; then, removing the pressure, continuously heating the first panel and/or the second panel, heating the optical adhesive film to reach a molten state, flowing between the first panel and the second panel, gradually filling a gap between the first panel and the second panel, and extruding bubbles between the first panel and the second panel to enable the first panel and the second panel to be attached more smoothly; and finally, curing the body to be cured to ensure that the first panel is firmly bonded with the second panel, thereby completing the bonding of the display screen.

In the traditional full-lamination process, the panel is subjected to a pressing effect in a hot pressing process and can generate micro deformation, so that stress is generated in the panel, and after the hot pressing is completed, the panel is warped and deformed due to stress release of the panel, so that the process is particularly obvious in lamination of a large-size display screen. In the large-size display screen attaching process in the embodiment of the invention, only the attaching tightness between the first panel and the second panel is properly improved during vacuum hot pressing, so that a primary bonding force is formed between the first panel and the second panel, after pressure is removed, in the process of continuously heating the first panel and/or the second panel, the first panel and the second panel release stress and recover freely, simultaneously, the optical adhesive film is gradually converted into a molten state, the optical adhesive flows freely between the first panel and the second panel and gradually fills a gap between the first panel and the second panel, so that the optical adhesive is filled between the two panels, therefore, in the continuous heating process, on one hand, the stress release of the first panel and the second panel is realized, the panels are prevented from warping and deforming in subsequent steps, on the other hand, the optical adhesive can be fully filled between the two panels, and the attaching smoothness of the first panel and the second panel is improved, thereby improving the bonding quality of the large-size display screen.

In addition, because the size of the display screen is large, the deformation and warping degree generated in the hot pressing process cannot be estimated, the stress of the panel can be fully released in a mode of enabling the panel to be freely recovered, enabling the adhesive film to freely flow and fill through continuous heating, enabling the adhesive film to be freely combined with the panel, and avoiding the existence of interaction force, thereby overcoming the defect that the display screen has Newton rings, yellowing or black mirror lines due to the fact that the panel is deformed and the filling is not in place.

The first panel can be a protective panel, and the protective panel can be a glass panel, a plastic panel or a functional panel with a touch function; the second panel may be a display panel, and the display panel may be a display module with a touch function or a display module without touch or other functions.

The Optical Adhesive film can be a UV-curable optically Clear Adhesive (TOCA) film, has high light transmittance and good ductility, can prevent the film from rebounding and warping and deforming, has strong self-adhesion, can be firmly adhered to the display panel and the protective panel, and improves the adhesion stability of the display panel and the protective panel.

In the vacuum hot-pressing step, the first panel and the second panel are subjected to only slight pressing force, so that the first panel and the second panel are tightly attached to each other, and the main purpose is to better close the two panels and discharge air between the first panel and the second panel through certain extrusion force; in addition, the optical adhesive film is not completely melted in the vacuum hot-pressing process, and the obtained effect is that the first panel and the second panel have certain adhesive force on the basis of mutual attachment. Therefore, compared with the step of completely melting the optical adhesive film in the traditional full-lamination vacuum hot pressing, the vacuum hot pressing step in the embodiment of the invention can save 5-10 times of time and greatly improve the lamination efficiency of the display screen.

The vacuum hot pressing and continuous heating process can be executed in a vacuum hot press, specifically, a body to be solidified is placed into the vacuum hot press to be quickly pressed through vacuum, so that a first panel and a second panel are mutually attached, the first panel and the second panel can generate micro deformation due to the pressing effect in the process, and the optical adhesive film has certain adhesive force; and then removing the pressing force on the first panel and the second panel, continuously heating the first panel and/or the second panel, converting the optical adhesive film into a molten state, wherein the molten adhesive film can freely flow and gradually fill air between the two panels due to the fact that the panels are not pressed, the molten adhesive film is combined with the surfaces of the panels, and meanwhile stress release of the panels and full contact with the adhesive film are achieved.

It should be noted that the continuous heating step is arranged in the vacuum hot press, so that bubbles between the first panel and the second panel can be sufficiently discharged, and the bonding quality between the panels can be further optimized. The continuous heating process can also be arranged in the atmosphere environment, so that the adhesive film extrudes air between the panels in the free flowing process.

In addition, after the vacuum hot pressing step is completed, the body to be solidified can be taken out and placed on a conveying line capable of continuously heating, or other processing equipment and processing platforms capable of continuously heating are convenient for the vacuum hot press to carry out vacuum fast pressing on other bodies to be solidified; and the continuous heating platform can heat a plurality of bodies to be cured simultaneously, the mass production of large-size display screens is supported, and the bodies to be cured can be transferred in the heating process through the conveying function of the continuous heating conveying line, so that the interval time between the vacuum hot pressing and the next working procedure is shortened.

It is contemplated that the continuous heating platform, continuous heating conveyor line, or vacuum hot press may heat the first panel, the second panel individually or simultaneously.

It should be noted that, a release film is usually attached to both sides of the optical adhesive film to protect the adhesive film on the inner layer of the optical adhesive film, and the release film has a certain elasticity and can be stretched, so as to prevent the optical adhesive film from rebounding during the process of attaching to the panel to cause the surface of the optical adhesive film to form wrinkles, the release film needs to be removed first, and then the adhesive film is attached. Therefore, before the adhesive film attaching step is performed, the release film on the first side of the optical adhesive film is removed to expose the adhesive film, the adhesive film is attached to the first panel, the release film on the second side is removed, and the side of the first panel to which the adhesive film is attached is aligned with the second panel, so that the first panel and the second panel are attached to each other.

In addition, can roll press optical adhesive film when optical adhesive film is attached, promptly, along with the glued membrane to first panel or the continuous attached of second panel, set up rolling press device (like rolling head, cylinder roller etc.) in glued membrane non-attached side and carry out synchronous roll extrusion to the glued membrane to make the glued membrane can level and smoothly get attached in the surface of first panel or second panel, thereby improve the compactness of laminating between glued membrane and the first panel, avoid appearing fold, bubble between glued membrane and the first panel, guarantee the laminating quality of laminating glue.

Referring to fig. 2, in an embodiment of the present invention, before the release film on the second side of the optical adhesive film is peeled off, the optical adhesive film is subjected to ultraviolet irradiation. Specifically, after the optical adhesive film is attached to the first panel, ultraviolet irradiation is performed on the side, to which the optical adhesive film is attached, of the first panel, so that pre-curing of the adhesive film is realized. The method that the adhesive film is irradiated firstly is adopted, the UV-cured optical adhesive film is contracted under the influence of the energy of internal functional groups and the molecular structure of the optical adhesive film, the optical adhesive film is aged, the stress after the adhesive film is attached can be reduced, the adhesive force and the bonding degree between the adhesive film and the first panel are improved, the release film on the other side of the adhesive film is torn off, and the adhesive film is prevented from being taken away from the first panel in the tearing process of the release film to influence the attachment flatness of the adhesive film; in addition, the glue film is in the hot pressing process, after the hot pressing plate is lifted, the edge of the glue film is easy to rebound, glue overflow at the edge of the panel is caused, and ultraviolet irradiation is carried out on the glue film in advance, so that certain bonding force is formed between the glue film and the panel, the glue film rebound is avoided, the flatness of the bonding glue is influenced, the glue film overflow can be avoided, and the bonding quality of the display screen is improved.

Therefore, in the embodiment of the invention, the optical adhesive film stress removing step and the panel stress removing step are arranged, and the combination of the optical adhesive film stress removing step and the panel stress removing step can greatly avoid the phenomena of panel warping, glue opening, Newton's rings and the like caused by the internal stress of the panel, the internal stress of the adhesive film and the acting force at the joint of the panel and the adhesive film, thereby effectively improving the joint quality of the large-size display screen.

After the vacuum hot-pressing step, the body to be cured is subjected to pressure defoaming so as to further remove bubbles between the first panel and the second panel, optimize the joint degree of the first panel and the second panel, and then a heat treatment step is performed. The pressurizing and defoaming step can improve the smoothness and the tightness of the joint between the first panel and the second panel, and improve the phenomenon that the joint glue is not converted or leveled. The defoaming process can be performed in a defoaming device, and the process can also be performed in a vacuum environment, and bubbles generated in the bonding glue during the bonding process are removed by using pressure and temperature. It should be noted that, because the flowing of the adhesive film in the continuous heating step has substantially eliminated the bubbles, the pressure deaeration here can adopt a rapid-pressure method, which can shorten the deaeration time and improve the lamination efficiency compared with the deaeration step of the conventional lamination process.

It should be noted that, after the heat treatment step is performed after the pressure deaeration, the stress concentration caused by the pressure of the belt curing body in the vacuum hot pressing and pressure deaeration processes can be simultaneously processed, so that the stress of the first panel and the second panel is released, and the panel is prevented from being rebounded in the pressure deaeration step after the heat treatment is performed on the panel, and warping and deformation are generated; and the vacuum hot pressing and the pressure defoaming are mutually connected, and the pressure defoaming step can further expel bubbles which are not discharged in the vacuum hot pressing, so that the effect of discharging the bubbles in the body to be cured is enhanced.

During and after the bonding process, the body to be cured can be detected. For example, after the hot pressing or the defoaming is completed, the appearance detection and the electrical property detection are performed on the first panel and the second panel, the appearance detection mainly detects whether the joint of the first panel and the second panel has an obvious non-joint part, a crack part and an overflow phenomenon, and the electrical property detection mainly detects whether the first panel and the second panel can normally display contents and whether the joint has a poor electrical connection part after the joint. If there is the laminating bad region, can tear the glued membrane between first panel and the second panel and remove, make glued membrane and first panel, second panel break away from, can carry out the adhesion to the glued membrane once more, and the aforesaid tears the process, does not damage the panel, and the simple operation, carries out prosthetic prerequisite to the laminating quality under, has reduced the rejection rate.

If no poor bonding area exists in the detection, the body to be cured can be cured, the curing step can adopt an ultraviolet curing mode, and the stress of the panel and the optical adhesive film is released, so that the adhesive film and the panel do not deform any more when subsequent curing is performed, the phenomena of Newton's rings, yellowing and the like of the display screen cannot occur, and the bonding force between the optical adhesive film and the first panel and between the optical adhesive film and the second panel can be increased through multiple times of curing, so that the bonding quality is improved.

In addition, if the first panel or the second panel has a wider ink shielding area, the ultraviolet rays cannot irradiate all areas of the first panel and the second panel, and an area which is not completely cured exists in the display screen, so that in order to further improve the curing effect, heating curing can be assisted after UV curing, the area which is not completely cured between the two panels is supplemented to be cured, the bonding strength between the first panel and the second panel is improved, and the curing quality of the display screen is optimized. In the heating and curing process, a frame body which is suitable for the ink area of the first panel and the frame size of the second panel can be adopted, and the frame body is heated and then directly hot-pressed to form the two panels, so that the heating and curing process is completed.

After the full solidification, the display screen can be subjected to final inspection, whether the joint of the first panel and the second panel meets the joint standard or not is observed, unqualified products can be separated from the first panel and the second panel by freezing and adopting a solvent method, and rework is carried out.

The large-size display screen attaching process provided by the embodiment of the invention is suitable for attaching large-size or ultra-large-size TV screens and display screens for education, supports the mass production of large-size display screens, and improves the attaching quality and the attaching efficiency of the display screens.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.