KR102043333B1 - Full-cover protection film for display device - Google Patents

Abstract

A full-cover protective film for a display device, comprising: a first film comprising a hard coating layer and a first base layer laminated thereunder; And a second film including a first transparent adhesive layer and a second substrate layer sequentially stacked below the first film, wherein the hard coating layer is an outermost layer of the protective film exposed to the outside, and the first film Disclosed is a full-cover protective film for a display device, wherein the base layer and the second base layer include a flexible resin.

Description

Full-cover protection film for display device {FULL-COVER PROTECTION FILM FOR DISPLAY DEVICE}

The present disclosure relates to a full-cover protective film for a display device. More specifically, the present disclosure relates to a protective film capable of full-covering the entire display device including the liquid crystal unit.

In order to protect the display device from various external shocks and contamination, a protective film or a protective case may be attached to the display device.

However, conventional protective films are not flexible enough and can easily be lifted up when attached to the edges and / or bends of the display device.

Therefore, in order to protect the display device, as shown in FIG. 1, only a plurality of protective films may be individually attached to the flat portions except for the edge portion and the curved portion, and thus, the entire display apparatus may not be completely protected.

In addition, in the case of the conventional protective case, as shown in Figure 2, the front case and the rear case may be applied in such a manner that the close contact with each other, the display device, it may have a higher hardness than the conventional protective film and This has the advantage of reducing the area that is not protected and exposed. However, since the material must be made of a hard and thick plastic material, the thickness of the display device may be increased, which may damage the grip of the display device. In addition, as shown in FIG. 2, voids may exist at the edge portion, and thus it may be difficult to completely protect the entire display device.

In particular, edge display devices or curved display devices have edges and / or bends of various shapes, and the liquid crystal part includes 2.5D glass or 3D glass. Therefore, when the conventional protective film is applied, the lifting phenomenon may be partially or totally deepened, and there is a fear of damage, and thus it is difficult to expect a sufficient protective effect.

Similarly, since the plastic protective case has a fixed shape due to the hard material, it is difficult to fully cover the various edge display devices or curved display devices.

Korean Unexamined Patent No. 2016-0004510 Korean Unexamined Patent No. 2009-0117466

One object of the present invention is an edge display device or a curved display device, which includes an edge portion and / or a curved portion having various shapes, in particular, a 2.5D glass or a 3D glass in the liquid crystal portion. display devices) to provide a protective film that can protect the entire device without lifting or damage.

Full-cover protective film according to an exemplary embodiment for achieving the object of the present invention, as a protective film capable of full-covering the entire display device including the liquid crystal portion, a hard coating layer and a lower portion thereof A first film comprising a first substrate layer laminated on the film; And a second film including a first transparent adhesive layer and a second substrate layer sequentially stacked below the first film. It includes. In this case, the hard coating layer is the outermost layer of the protective film exposed to the outside.

In exemplary embodiments, the thickness of the base layer including the flexible resin under the hard coating layer is adjusted to a thin thickness to ensure flexibility. To this end, the first base material layer and the second base material layer may include a flexible resin and have a thickness of 10 μm to 50 μm, respectively. In addition, the hard coating layer may have a thickness of 30㎛ 50㎛. Accordingly, the protective film may have a hardness of more than 2H 9H or less, preferably 4H or more and 9H or less under a 750g load.

In example embodiments, the protective film may further include a transparent adhesive film laminated under the second film and for attaching the protective film to the display device.

In exemplary embodiments, the flexible resin may be polyethylene terephthalate (PET), urethane, polymethyl methacrylate (PMMA), polycarbonate, or polyimide. It may be one or more selected from the group consisting of.

In example embodiments, the protective film may include: a third film including a second transparent adhesive layer and a third substrate layer sequentially stacked below the second film; And a transparent adhesive film laminated on the lower portion of the third film and for attaching the protective film to the display device. In this case, the third substrate layer may include a flexible resin.

In example embodiments, the third base layer may have a thickness of 10 μm to 50 μm, similarly to the first base layer or the second base layer.

In exemplary embodiments, the flexible resin may be polyethylene terephthalate (PET), urethane, urethane, polymethyl methacrylate (PMMA), polycarbonate, or polyimide. It may include one or more selected from the group consisting of.

In exemplary embodiments, the total thickness of the protective film may be 20 μm to 500 μm.

In example embodiments, the display device may be an edge display device or a curved display device including 3D glass or 2.5D glass in the liquid crystal unit.

The full-cover protective film according to exemplary embodiments of the present invention not only has excellent hardness and impact resistance, but also has excellent flexibility and moldability, so that the entire display device such as a smartphone or a tablet PC can be substantially applied. Can be completely wrapped and protected.

In particular, all of the edge display devices or curved display devices having edges and / or bends of various shapes and including 2.5D glass or 3D glass in the liquid crystal part using the protective film. It is useful because it can be wrapped tightly without lifting or damage.

That is, as shown in Figure 4, since one of the protective film can be applied in a manner that wraps around the entire display device, for example, except for the rear interface (side where both sides of the full cover protective film meet) Dust may not enter the display device. In addition, since the exposed area of the display device is minimized than using a conventional protective film or protective case, the display device can be protected more strongly.

1 illustrates how a conventional protective film is applied to a display device.
2 illustrates how a conventional protective case is applied to a display device.
3 illustrates a cross-sectional view of a full-cover protective film for a display device, in accordance with exemplary embodiments of the present invention.
4 is a schematic diagram illustrating a cross-sectional view of a full-cover protective film for a display device, in accordance with exemplary embodiments of the present invention.
FIG. 5 is a schematic diagram illustrating how a full-cover protective film is applied to a display device according to exemplary embodiments of the present invention. FIG.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Full-cover protective film for display devices

3 illustrates a cross-sectional view of a full-cover protective film in accordance with exemplary embodiments of the present invention.

Referring to FIG. 3, the protective film 100 may include a first film 10, a second film 20, and a transparent adhesive film 40.

The first film 10 is to provide the protective film 100 with appropriate hardness, scratch resistance, flexibility, and moldability. The first film 10 is laminated on the hard coating layer 11 and the lower part thereof and includes a flexible resin. (13) may be included.

The second film 20 is to provide adequate flexibility, moldability and impact resistance to the protective film 100, and the first transparent adhesive layer 22 and the flexible resin sequentially stacked below the first film 10. It may include a second substrate layer 23 including.

The transparent adhesive film 40 is for attaching the protective film 100 to the entire display device, and is stacked below the second film 20.

The hard coating layer 11 is an outermost layer of the protective film 100 exposed to the outside, and may substantially protect the entire display device including the liquid crystal part from an external physical shock such as a direct touch or a scratch of a user. To this end, the hard coating layer 11 preferably has a hardness of more than 2H under a 750g load, and thus may have a thickness of about 30 μm or more.

More specifically, the hard coating layer 11 may have a thickness of about 30 μm or more to about 50 μm or less. When the hard coating layer 11 has a thickness of less than about 30 μm, the hard coating layer 11 may be too thin and have a hardness of 2H or less, more specifically 1H to 2H under a 750g load. As a result, in the protective film 100 in proportion to the low hardness, there may be pressed marks, stamp marks, etc. due to external impact. Since the impact resistance of the protective film 100 is reduced, the liquid crystal unit and the display device including the same may be easily damaged. In addition, when the hard coating layer 11 has a thickness greater than about 50 μm, the hardness of the protective film 100 may be improved, but the hard coating layer 11 may be too thick, thereby decreasing the flexibility and formability of the protective film 100. Can be. As a result, the protective film 100 includes the entire display device, in particular the various edge portions and / or bends, and includes all of the edge display devices or curved display devices including 2.5D glass or 3D glass in the liquid crystal portion. Curved display devices) It may be difficult to effectively protect the display device at least partially lifted when wrapping the whole.

Accordingly, the hard coating layer 11 preferably has a thickness of about 30 μm to about 50 μm, and thus may have a hardness of more than 2H and less than 9H, preferably 4H and less than 9H under a 750g load.

The hard coating layer 11 is not particularly limited as long as it is transparent and can realize the hardness as described above, but may be, for example, a photocurable hard coating layer. In one embodiment, the hard coating layer 11 may be a cationic type photocurable hard coating layer based on an epoxy resin. Accordingly, the hard coating layer 11 may include a cationic curing type initiator, and further include a leveling agent, an antifoaming agent, a silicon type inorganic material, and the like as an additive in consideration of physical properties and processing characteristics of the hard coating layer 11. Can be.

Each of the first base layer 13 and the second base layer 23 may include a flexible resin to impart flexibility and moldability to the protective film 100, and the first transparent adhesive layer 22 may be provided therebetween. It is laminated through the hard coating layer 11 can absorb the external impact. In particular, the protective film 100 includes two or more substrate layers having a relatively thin thickness through the first substrate layer 13 and the second substrate layer 23, thereby, for example, beneath the hard coating layer 11. Much more flexible than when a single layer of substrate layer having a thickness substantially the same as or similar to the sum of the total thicknesses of the first substrate layer 13 and the second substrate layer 23 is more advantageous for the entire display device full-cover. have.

The flexible resin is not particularly limited as long as it is transparent and can have an appropriate level of flexibility, moldability, and impact resistance. methacrylate, PMMA), polycarbonate, polyimide, and the like.

Meanwhile, the first base layer 13 and the second base layer 23 may each have a thickness of about 10 μm or more and about 50 μm or less, for example. When the first base material layer 13 or the second base material layer 23 has a thickness of less than about 10 μm or a thickness of more than about 50 μm, the thickness of the base material layer, and the base layer relative to the hard coating layer 11 Their total thickness may be so thin or thick that it is difficult for the protective film 100 to have adequate levels of flexibility, formability, hardness (greater than 2H), impact resistance and transparency (transmittance). As a result, the protective film 100 may be difficult to sufficiently cover the edge portion and / or curved portion of the display device without lifting.

In an exemplary embodiment, the first base layer 13 and the second base layer 23 have substantially the same thickness and may include the same flexible resin such as polyethylene terephthalate (PET).

The first transparent adhesive layer 22 may be, for example, an optically clear adhesive layer (OCA layer). The thickness of the first transparent adhesive layer 22 is not particularly limited, and an appropriate adhesive force between the first substrate layer 13 and the second substrate layer 23, and an appropriate elastic force and optical properties required for the first transparent adhesive layer 22. It may have a variety of thickness depending on the.

The transparent adhesive film 40 may be, for example, a pressure sensitive adhesive film (PSA film) that is transparent and capable of double-sided adhesion and adhesion separation. The transparent adhesive film 40 may have an appropriate elastic force and adhesive force, and may further have excellent properties such as heat resistance and cold resistance. The thickness of the transparent adhesive film 40 is not particularly limited, and may have various thicknesses according to the thickness, application area, etc. of the protective film 100 so that the protective film 100 may cover the entire display device.

In one exemplary embodiment, as shown in FIG. 1, the protective film 100 having a two-layer structure including the first film 10 and the second film 20 is preferably about 70 to 250 μm. Can have a total thickness. Such a protective film may have a hardness of more than 2H to 9H, preferably 4H or more and 9H or less under 750 g load, and may have improved moldability.

4 illustrates a cross-sectional view of a protective film in accordance with exemplary embodiments of the present invention. The protective film may have a structure substantially the same as or similar to that of the protective film described with reference to FIG. 3 except for the third film 30. Therefore, like reference numerals refer to like elements, and detailed description thereof will be omitted.

Referring to FIG. 4, the protective film 110 may include a first film 10, a second film 20, a third film 30, and a transparent adhesive film 40.

The first film 10 and the second film 20 may be substantially the same as those of the protective film 100 described with reference to FIG. 3. The third film 30 is to provide adequate flexibility, moldability and impact resistance to the protective film 110, the second transparent adhesive layer 32 is sequentially laminated to the lower portion of the second film (20); And a third base layer 33 including a flexible resin. The transparent adhesive film 40 is for attaching the protective film 110 to the entire display device. The transparent adhesive film 40 is substantially the same as that of the protective film 100 described with reference to FIG. 3, and is stacked below the third film 30. .

The second transparent adhesive layer 32 may be, for example, an optically clear adhesive layer (OCA layer). The thickness of the second transparent adhesive layer 32 is not particularly limited, and may provide a suitable adhesive force between the second substrate layer 23 and the third substrate layer 33 and may be appropriately required for the first transparent adhesive layer 22. Various modifications are possible within the range in which the elastic force and the optical property can be realized. In one embodiment, the second transparent adhesive layer 32 may be substantially the same as the first transparent adhesive layer 22.

The third base layer 33 is not particularly limited as long as it is transparent and can implement an appropriate level of flexibility, moldability, and impact resistance, and may include various kinds of flexible resins. The third base layer 33 is, for example, polyethylene terephthalate (PET), urethane, polymethyl methacrylate (PMMA), polycarbonate, polyimide, or the like. It may include a flexible resin. For example, the third base layer 33 may have a thickness of about 10 μm or more to about 50 μm or less. In one embodiment, the third substrate layer 33 may be substantially the same as the first substrate layer 13 and / or the second substrate layer 23.

In one exemplary embodiment, the protective 110 film having a three-layer structure, including the first film 10, the second film 20, and the third film 30 as shown in FIG. 4, is preferably May have a total thickness of about 90 to 350 μm. In addition, such a protective film may have a hardness of more than 2H to 9H, preferably 4H or more and 9H or less under 750 g load, and may have improved moldability.

As described above, the protective film according to the exemplary embodiments of the present invention not only has excellent hardness and impact resistance, but also has excellent flexibility and moldability, so that the entire display device such as a smartphone or tablet PC is substantially completely replaced. I can wrap it and protect it. In particular, all of the edge display devices or curved display devices having edges and / or bends of various shapes and including 2.5D glass or 3D glass in the liquid crystal part using the protective film. It is useful because it can be wrapped tightly without lifting or damage.

That is, as shown in Figure 4, since one of the protective film can be applied in a manner that wraps around the entire display device, for example, except for the rear interface (the side where both sides of the protective film meet) the corresponding display Dust may not enter the device. In addition, since the exposed area of the display device is minimized than using a conventional protective film or protective case, the display device can be protected more strongly.

In the above description, a structure in which the second film 20 is stacked below the first film 10 or the second film 20 and the third film 30 are stacked, that is, under one hard coating layer that can realize an appropriate hardness Only a protective film having a structure in which two to three substrate layers are laminated to realize appropriate flexibility has been described.

However, as long as the characteristics of the present invention, the number of laminated films (the number of substrate layers stacked below the hard coating layer to realize flexibility) may be added. For example, a protective film having a structure substantially the same as or similar to that of the present invention, that is, a protective film having a structure in which four or more base layers including a flexible resin are laminated under the hard coating layer (eg, a hard coating layer, a first base layer, and a first layer). A four-layered protective film (not shown), including a second substrate layer, a third substrate layer, and a fourth substrate layer, preferably having a total thickness of about 110 to 450 μm, and a display device including the same. It will be apparent to those skilled in the art that it is included in the scope of the invention.

As described above, the protective film according to the exemplary embodiments of the present invention is a protective film capable of full-covering the entire display device including the liquid crystal part, the hard coating layer; It is flexible and excellent in moldability by having a multilayer structure including a; and a plurality of thin substrate layer laminated on the lower portion and including a flexible resin. Accordingly, the protective film has not only flat display devices but also various curved and / or edge portions and includes 3D glass or 2.5D glass in the liquid crystal portion, edge display devices or curved displays. The entire curved display devices can be rolled up tightly without lifting.

In addition, unlike most conventional protective films except glass having a low hardness of 1H to 2H, the protective film includes a hard coating layer having an appropriate thickness, thereby exceeding the hardness range of conventional protective films under a load of 750 g. In detail, the display device including the liquid crystal part may be effectively protected by having a hardness of more than 2H to 9H, preferably 4H or more and 9H or less.

Manufacturing method of full-cover protective film for display device

The full-cover protective film according to exemplary embodiments of the present invention may be prepared by performing the following processes.

To prepare a protective film having a cross-sectional structure as shown in FIG. 3, a hard coating layer is formed on one surface of the first base layer including a flexible resin and having a thickness of about 10 μm or more and 50 μm or less. In exemplary embodiments, the hard coating layer is light-cured by applying a photocurable hard coating composition on one side of the first substrate layer, and finally, about 30 μm or more, specifically, It may be formed to have a thickness of about 30㎛ or more to 50㎛ or less.

Applying an optical transparent adhesive (OCA) on the other surface of the first base layer without the hard coating layer to form a first transparent adhesive layer, using the first transparent adhesive layer of about 10㎛ or more and 50㎛ or less A second base layer having a thickness of and containing a flexible resin is laminated to the first base layer.

Thereafter, a transparent pressure-sensitive adhesive (PSA) is applied on a surface of the second base layer that is not in direct contact with the first transparent adhesive layer, thereby forming a transparent adhesive film that may be in direct contact with glass and a display device including the same. .

Alternatively, a protective film having a cross-sectional structure as shown in FIG. 4 may be manufactured using a method substantially the same as or similar to that described above.

That is, by using a method substantially the same as or similar to that described above, a hard coating layer is formed on one surface of the first substrate layer, and the first sequentially on the other surface of the first substrate layer on which the hard coating layer is not formed. The transparent adhesive layer and the second substrate layer are formed.

Forming a second transparent adhesive layer using a method substantially the same as or similar to that of forming the first transparent adhesive layer, and using the same to form a third substrate layer having a thickness of about 10 μm or more and 50 μm or less and including a flexible resin. It is laminated to the said 2nd base material layer.

Thereafter, using a method substantially the same as or similar to that described above, a transparent adhesive film capable of directly contacting the glass and the display device including the same is formed.

Exemplary embodiments of the present invention are described in more detail through the following examples. The embodiments disclosed herein are for illustrative purposes only, and embodiments of the present invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein.

EXAMPLE

A 75 μm-thick first film was formed by forming a 35 μm-thick hard coating layer on the one surface of the 40 μm-thick first base layer including PET by a photocuring method using a cation curing type resin.

After forming the first transparent adhesive layer by applying OCA on the other side of the first base layer, the hard coating layer is not formed, a second substrate layer having a thickness of 40㎛ including the first substrate using the first substrate It was laminated to the layer to form a second film laminated below the first film.

By using the same method as in forming the second film, a second transparent adhesive layer (OCA layer) is sequentially formed on the lower part of the second film, and a third substrate layer having a thickness of 40 μm including PET is formed. A film was formed.

Thereafter, PSA was applied on the surface of the third base layer not in contact with the second transparent adhesive layer to form a transparent adhesive film laminated under the third film.

Thus, a protective film including a first film, a second film, a third film, and a transparent adhesive film and having a thickness of about 155 μm in total was prepared.

The protective film was attached to the full cover of the cell phone without cutting it separately.

Comparative Example 1

It was made and manufactured in the same manner as in Example, the prepared protective film was cut into 4 pices and attached to each side so as to be attached to both the upper and lower surfaces of the mobile phone.

Comparative Example 2

Polycarbonate (or polypropylene may be used) was used as a hard plastic material. In other words, the above materials were melted in a mold, injected, and cured to manufacture a pair of protective cases that can be fitted to the front and rear of the mobile phone, respectively. The sides or ends were cut and trimmed to fit the shape of the mobile phone. .

evaluation

In order to evaluate the physical properties and the like of the full-cover protective film for display devices, the total thickness and hardness of the protective films of Example 1 and Comparative Example 1 and the protective case of Comparative Example 2 were measured and compared. The full-cover characteristics were compared and evaluated. At this time, the hardness was measured by tilting Mitsubishi's pencil at a 45 ° angle under a 750g load. The measurement results are as shown in the following [Table 1].

Example Comparative Example 1 Comparative Example 2 Total thickness About 155㎛ About 155㎛ 500㎛ or less Hardness 3H ~ 9H 3H ~ 9H 3H ~ 9H flexibility ◎ ◎ X Protection method One film is rolled and attached to the entire display device body using the adhesive layer. Using adhesive layer, the films are individually attached to each side of the display device. Fits individual cases into the front and back of the display unit Full Coverage Assessment ◎ X
(No edge cover) △
(Edge void)

Among the results of the full cover possibility evaluation,? Denotes wrapping without edge lift or edge voids, and? Means edge lift or edge voids. Edge lifting is a phenomenon in which the protective film is lifted up at the edge part as a whole, and the edge void means that the protective film is stuck at the edge part, but voids (or bubbles) are formed therebetween. X means no edge cover.

While non-limiting and exemplary embodiments of the present invention have been described above, the technical idea of the present invention is not limited to the accompanying drawings and the description. It will be apparent to those skilled in the art that various forms of modifications can be made without departing from the spirit of the present invention, and furthermore, such modifications will be within the scope of the claims of the present invention.

10, 20, 30: first to third film
11: hard coating layer
13, 23, 33: 1st to 3rd base material layer
22, 32: first and second transparent adhesive layer
40: transparent adhesive film
100, 110: full-cover protective film
200: display device main body

Claims (8)

A display device full-covered with a full-cover protective film for a display device,
The protective film,
A first film comprising a hard coating layer and a first base layer laminated thereunder; And
And a second film including a first transparent adhesive layer and a second substrate layer sequentially stacked below the first film.
The hard coat layer is the outermost layer of the protective film exposed to the outside,
The first base material layer and the second base material layer includes a flexible resin and each has a thickness of 10 μm or more and 50 μm or less,
The protective film is to cover the entire display device including the liquid crystal portion,
The display device may be an edge display device or a curved display device including 3D glass or 2.5D glass in a liquid crystal part.
And the full-cover protective film full-covers edge display devices or curved display devices without edge lift or edge voids.
The method of claim 1,
The protective film is a display device, characterized in that having a hardness of more than 2H 9H or less under 750g load.
The method of claim 1,
The protective film is laminated on the lower portion of the second display device, characterized in that further comprising a transparent adhesive film for attaching the protective film to the display device.
The method of claim 1,
The protective film
A third film including a second transparent adhesive layer and a third substrate layer sequentially stacked below the second film; And
A transparent adhesive film laminated on the lower part of the third film and for attaching the protective film to the display device; More,
The third substrate layer includes a flexible resin, and has a thickness of 10 μm or more and 50 μm or less.
The method according to any one of claims 1 to 4,
The flexible resin is at least one selected from the group consisting of polyethyleneterephthalate (PET), urethane, urethane, polymethyl methacrylate (PMMA), polycarbonate, and polyimide. Display device comprising a.
The method of claim 1,
The hard coating layer is a display device, characterized in that having a thickness of 30㎛ 50㎛.
The method of claim 1,
The total thickness of the protective film is a display device, characterized in that 20㎛ to 500㎛.
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