KR101526353B1 - Touch screen panel protection sheet - Google Patents

Abstract

The present invention relates to a liquid crystal protective sheet for protecting a touch screen panel of a display display terminal, the liquid crystal protective sheet comprising: a sapphire sheet processed to fit a display panel size; An ultra thin film anti-fouling coating layer formed on the upper surface of the sapphire sheet; A low adhesive layer formed on the lower surface of the anti-scattering film by a low adhesive silicone coating; And a high adhesion layer formed on the top surface of the shrinkage preventing film by a high adhesion acrylic or a high adhesion silicone coating, wherein the high adhesion layer is formed on the lower surface of the sapphire sheet having the anti-fouling coating layer.
The liquid crystal protective sheet of the present invention can provide a liquid crystal protective sheet superior in surface hardness, compressive strength and rigidity to tempered glass because sapphire monocrystals having hardness higher than diamond are used instead of tempered glass. Since the liquid crystal protective sheet is superior to the tempered glass, it is possible to provide a liquid crystal protective sheet with a thinner thickness, and it is possible to guarantee a fine touch sensing ability and to provide a liquid crystal protecting sheet with a remarkably low possibility of being damaged during production or distribution and use There is an effect that can be.

Description

{TOUCH SCREEN PANEL PROTECTION SHEET}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a touch screen panel protection sheet, and more particularly, to a liquid crystal protection sheet for protecting a touch screen panel of a display display terminal.

As the spread of display display terminals (mobile phones, smart phones, notebooks, tablet PCs, digital cameras, navigation devices, game devices, robots, electronic notebooks, etc.) using touch screen panels such as LCDs, PDPs and OLEDs has dramatically expanded, A touch screen panel with a convenient touch function is rapidly enlarged and used.

For the purpose of protecting the screen panel which should be frequently touched and preventing scratches, it is preferable to use a film such as PET (Poly-Ethylene Terephthalate) film, PMA (Poly Methyl Acrylate) or PC (Poly Carbonate) -PMMA laminate sheet, Liquid crystal protection sheets are spread.

The PET film is inexpensive, has a transmittance of 90% or more, and has an advantage of being easy to mass-produce, but has a disadvantage that the scratch resistance is poor and the impact protection function is poor. On the contrary, PMMA or PC-PMMA laminate sheet has a transmittance of 90% or more, higher price than PET, low price compared to glass, and mass production at an intermediate level, but also has a weak scratch resistance.

On the other hand, the tempered glass laminated sheet has an advantage that its surface hardness is as high as about 9H as compared with the above-mentioned sheets. However, since the thickness of the used tempered glass laminated sheet is made as thin as about 0.1 mm to 0.5 mm, And there are many disadvantages such as cracking during distribution and consumer use, and scratches even though hardness is about 9H.

Therefore, the development of a new type of liquid crystal protection sheet capable of overcoming the problems in the above-mentioned various sheets by using a material having a high surface hardness, a high compressive strength and a high rigidity while maintaining a thin thickness to guarantee a fine touch sensing capability It is desperately required.

Furthermore, since the liquid crystal protective sheet is attached to the front of the display and the touch screen, it is preferable that the material is harmless to the human body. In particular, in order to reduce eye fatigue and protect the eyesight, a UV light and a blue light It is necessary to develop a liquid crystal protection sheet using a material having a high transmittance in the visible light region.

Accordingly, the present invention has been made in view of the above-described needs, and it is an object of the present invention to provide a method of manufacturing a semiconductor device having a surface hardness, a compressive strength and a hardness higher than that of a glass while maintaining a thin thickness, A first object of the present invention is to provide a liquid crystal protective sheet having remarkably low transparency,

It is still another object of the present invention to provide a light source that can maximize the transmittance of the visible light region while blocking the light of the ultraviolet (UV) and high energy blue light region so as to reduce eye fatigue and protect the eyesight And a liquid crystal protection sheet.

According to an aspect of the present invention, there is provided a liquid crystal protective sheet comprising:

A sapphire sheet processed to fit the display panel size;

An ultra thin film anti-fouling coating layer formed on the upper surface of the sapphire sheet;

A low adhesive layer formed on the lower surface of the anti-scattering film by a low adhesive silicone coating;

And a high adhesion layer formed on the upper surface of the shrinkage preventing film by a high adhesion acrylic or a high adhesion silicone coating, wherein the high adhesion layer is formed on the lower surface of the sapphire sheet with the anti-fouling coating layer formed thereon.

Further, according to another embodiment of the present invention,

A sapphire sheet processed to fit the display panel size;

A functional thin film layer formed on a lower surface of the sapphire sheet;

An ultra thin film anti-fouling coating layer formed on an upper surface of the sapphire sheet;

And a high adhesion layer formed on each of the upper and lower surfaces of the anti-scattering film, wherein the high adhesion layer is formed by removing the release film on the lower surface of the sapphire sheet having the functional thin film layer formed on the lower surface thereof. ,

The sapphire sheet is characterized by having a thickness of 0.05 mm to 0.5 mm as a sapphire single crystal having a light transmittance of 83% or more.

According to the above-mentioned problem solving means, since the liquid crystal protective sheet of the present invention uses a sapphire single crystal having a hardness higher than that of diamond instead of tempered glass, the surface hardness, the compressive strength and the rigidity are superior to the tempered glass Sheet can be provided,

Since the strength of the liquid crystal protective sheet is superior to that of tempered glass, it is possible to provide a liquid crystal protective sheet with a thinner thickness, and it is possible to guarantee a fine touch detection force and to provide a liquid crystal protection sheet having a remarkably low possibility of being damaged during production, Can be provided.

Furthermore, since the liquid crystal protective sheet of the present invention has high transmittance in the visible light region while blocking light in the ultraviolet (UV) and high energy blue light region, it is possible to reduce the eye fatigue and protect the eyesight The effect can be expected.

1 is a cross-sectional exemplary view of a liquid crystal protection sheet according to an embodiment of the present invention;
2 is a cross-sectional exemplary view of a liquid crystal protection sheet according to another embodiment of the present invention.
Fig. 3 is a graph showing a comparison graph of transmittance of tempered glass and tempered glass for protecting liquid crystal. Fig.
Fig. 4 is a graph showing a comparative graph of transmittance of tempered glass and sapphire. Fig.
FIGS. 5, 6A and 6B are diagrams illustrating a comparison graph of transmittance of sapphire sheet and sapphire using sapphire according to an embodiment of the present invention. FIG.
7 is a cross-sectional exemplary view of a liquid crystal protection sheet according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

의 단결정체로서, 물리적으로도 견고하고 무엇보다 경도(hardness)가 다이아몬드 다음으로 강해 스크래치가 없으며, 물리적 특성 때문에 유리 보다 얇게 만들어도 안정하다. 동일 두께에서 견고성을 분석해 보면 강화유리가 674Kgf/㎠ 인데 반해 사파이어는 1850∼2200Kgf/㎠로 월등한 견고성을 가진다. 아울러 사파이어 단결정체의 투과율은 거의 모든 파장대에서 약 85% 대 이상을 유지하며, 블루 라이트(Blue light) 차단율은 유리(차단율 약 10%)에 비해 약 5% 더 차단하는 특성을 보인다.1 is a cross-sectional view of a liquid crystal protection sheet according to an embodiment of the present invention. In the liquid crystal protection sheet according to an embodiment of the present invention, sapphire monocrystals are used instead of tempered glass. Sapphire is structurally

Which is physically strong, above all hardness harder than diamonds and has no scratches, and is stable even if made thinner than glass due to its physical properties. Analysis of the hardness at the same thickness shows that the tempered glass is 674 Kgf / ㎠, while the sapphire has a superior hardness at 1850 ~ 2200 Kgf / ㎠. In addition, the transmittance of the sapphire monocrystals is maintained at about 85% or more in almost all wavelength ranges, and the blue light blocking rate is about 5% more than the glass (blocking rate is about 10%).

According to the physical properties of the sapphire single crystal, sapphire single crystals are used instead of tempered glass in the liquid crystal protective sheet according to the embodiment of the present invention.

Referring to FIG. 1, a process of preparing sapphire before manufacturing a liquid crystal protective sheet according to an embodiment of the present invention will be described.

Sapphire monocrystalline ingots are grown by the Bernoulli method, the Bridgman method, the edge-defined film-feed growth (EFG) method, the Czochralski method, the Kiroplus method and the heat exchange method (HEM) .

Thereafter, the cylindrical sapphire ingot is sliced into a sheet, and the cut sapphire is subjected to double-side polishing using a polishing slurry including a hard plate such as diamond abrasive grains and tin and colloidal silica And a final mechanical finish by a chemical mechanical polishing process in which the surface is planarized by chemical action and mechanical action.

In this way, the double-sided lapping sapphire is fabricated in a cell size suitable for the front panel of a smartphone and a tablet PC using a laser cutting or a chemical etching method.

If the corners and edges of the cell-processed sapphire are not sharp and there are no microcracks, they can be used in cell-processed form to make liquid crystal protective sheets. However, if there are sharp edges and fine cracks, cell processed sapphire is used by grinding and polishing.

When the sapphire sheet (the thickness of the sapphire is preferably 0.05 mm to 0.5 mm or less) prepared according to the display panel size of the smartphone or the tablet PC through the above process is prepared, as shown in Fig. 1 (a) An ultra thin film antifouling coating layer 102 is formed on the upper surface of the sheet 100 by using a wet coating method using a metal deposition or coating liquid.

In order to form the anti-scattering layer 106, a low adhesive layer 108 is formed on the lower surface of a shatterproof film (using PET or TPU (Thermoplastic Polyurethane): 20 to 200 mu m) to form a low adhesive layer 108, A high adhesion acrylic or a high adhesion silicone coating is applied to the upper surface of the anti-fake film to form a high adhesion layer 104. [

The high adhesion layer 104 from which the release film of the high adhesion layer 104 is removed is joined to the lower surface (i.e., the back surface) of the sapphire sheet 100 on which the antifouling coating layer 102 is formed to complete the liquid crystal protection sheet using sapphire.

The liquid crystal protection sheet having the sectional structure shown in Fig. 1 (b) can be produced differently from the sectional structure shown in Fig. 1 (a).

When the sapphire sheet 100 processed according to the display panel size of the smartphone or the tablet PC is prepared through the process described with reference to FIG. 1 (a), the sapphire sheet 100 having the functional layer A thin film layer 110 is formed. For example, an anti-reflection coating for improving the transmittance using a process of depositing a metal component under vacuum, an electromagnetic shielding coating for electromagnetic shielding, a mirror coating for giving a mirror effect, a blue light shielding A transparent or translucent color printing layer, a letter or a logo is locally applied to the backside of the sapphire sheet 100 using a coating, a silk screen, a pad, a digital printing, and a transferring process to form a functional thin film layer 110 .

When the functional thin film layer 110 is formed on the back surface of the sapphire sheet 100, an ultra thin film anti-fouling coating layer 102 is formed on the upper surface of the sapphire sheet 100 using a wet coating method using a metal deposition or coating solution.

Adhesion layer 104 and a low adhesive layer 108 are formed on the upper and lower surfaces of the anti-scattering layer 106 and the lower surface (i.e., the back surface) of the sapphire sheet 100 on which the antifouling coating layer 102 is formed, The process of completing the liquid crystal protection sheet by laminating the high adhesive layer 104 from which the release film of the adhesive layer 104 is removed is the same as that described with reference to FIG. 1 (a), and a duplicated description thereof will be omitted.

2 is a cross-sectional view illustrating a process for fabricating a liquid crystal protective sheet according to another embodiment of the present invention.

Referring to FIG. 2A, when the sapphire sheet 100 processed according to the display panel size of a smartphone or a tablet PC is prepared through the process described in FIG. 1A, The ultra thin film anti-fouling coating layer 102 is formed on the upper surface of the sapphire sheet 100 by using a wet coating method using a metal deposition or coating liquid as shown in (a) of FIG.

The functional thin film layer 110 as shown in FIG. 1 (b) is formed on the upper surface of the anti-scattering film 106 (PET / TPU) corresponding to the anti-scattering layer 106, Sensitive adhesive layer 108 is formed on the lower surface of the functional thin film layer 106 by coating the lower surface of the functional adhesive layer 106 with a high adhesive layer 104 ). Then, the high adhesive layer 104, from which the release film of the high adhesion layer 104 is removed, is joined to the lower surface of the sapphire sheet 100 to complete the liquid crystal protection sheet.

The liquid crystal protection sheet having the cross-sectional structure shown in Fig. 2 (b) can be produced differently from the cross-sectional structure shown in Fig. 2 (a). That is, the functional thin film layer 110 may be formed on the sapphire sheet 100 and the anti-scattering layer 106 to produce a liquid crystal protection sheet having a plurality of effects and performance.

1 (b), a functional thin film layer 110 is formed on the lower surface of the sapphire sheet 100, an antifouling coating layer 102 is formed on the upper surface of the sapphire sheet 100, Another low-adhesion layer 108 is formed on the lower surface of the anti-scattering layer 106 and a high adhesion layer 104 is formed on the upper surface of the functional thin layer 110. In addition, The liquid crystal protection sheet may be completed by joining the high adhesive layer 104 obtained by removing the release film of the high adhesive layer 104 to the lower portion of the sapphire sheet 100 on which the functional thin film layer 110 is formed.

In the process of manufacturing such a liquid crystal protective sheet, the order of the adhesive of the anti-scattering layer 106, that is, the high adhesion and low adhesion coating may be changed, and the release film may be laminated on both sides for protection and processing It is possible. In addition, the ultra-thin antifouling coating may be a post-lamination process.

For reference, FIG. 3 illustrates a comparative graph of transmittance of tempered glass and tempered glass liquid crystal protective sheet. The transmittance of a reinforced glass liquid crystal protective sheet composed of a double-sided adhesive tape, a PET shatterproof film and a silicone adhesive at the bottom of the glass using tempered glass is as shown in Fig. 3 and Table 1. [

wavelength Liquid crystal protection tempered glass (%) tempered glass(%) 250 nm 0.4 0.6 300 nm 0.3 23.2 350 nm 79.1 88.7 380 nm 88.0 90.4 450 nm 91.1 91.3 550 nm 91.2 91.6

 Specifically, the UV cut-off rate is 99.7% at 300 nm and 20.9% at 350 nm, and the other transmittances are the same. This means that the liquid crystal protective glass has a somewhat higher UV cut-off than glass.

Therefore, the transmittance is preferably lower (i.e., the UV cut rate is higher) in the UV region of 380 nm or less than that of the liquid crystal protective sheet using the tempered glass, the transmittance is low in the blue light region of 380 to 495 nm That is, it is preferable that the transmittance is high in the visible light region (that is, the cutoff rate is low).

4 is a graph showing a comparative transmittance of tempered glass and sapphire.

wavelength tempered glass(%) Sapphire(%) 250 nm 0.6 83.8 300 nm 23.2 84.7 350 nm 88.7 85.6 380 nm 90.4 85.6 450 nm 91.3 85.9 550 nm 91.6 86.0

Referring to Table 2 and FIG. 4, the sapphire has a transmittance of about 85% in all the UV, visible, and infrared regions. Although the tempered glass shows higher transmittance than the sapphire in the visible light region, it has a lower transmittance characteristic than the tempered glass in the blue light region of 350 nm or more.

FIG. 5 is a graph showing a comparative transmittance of a sapphire liquid crystal protective sheet and sapphire according to an embodiment of the present invention. More specifically, as shown in FIGS. 1 and 2, In which a sapphire liquid crystal protective sheet is produced, and the transmittance is measured.

wavelength
Sapphire(%) Sapphire liquid crystal protection
Sheet (PET) (%) Sapphire liquid crystal protection
Sheet (TPU) (%) 250 nm 83.8 0.4 0.3 300 nm 84.7 0.3 0.6 350 nm 85.6 77.5 0.3 380 nm 85.6 85.2 37.5 450 nm 85.9 88.1 87.6 550 nm 86.0 89.2 90.1

As shown in Table 3 and FIG. 5, it can be seen that the sapphire liquid crystal protective sheet according to the embodiment of the present invention has a blue light blocking rate improved by about 3% as compared with the liquid crystal protective sheet using the tempered glass of FIG. The visible light transmittance (550 nm) is about 89.2%, which is about 3% lower than that of the tempered glass liquid crystal protective sheet, but it can be used as a liquid crystal protective sheet having a blue light blocking performance. Rather, the transmittance of sapphire itself was 86% at 550 nm, but the transmittance of the sapphire liquid crystal protective sheet was improved to 3.2% at 550 nm to 89.2%. This improvement in transmittance can be interpreted as a result of using sapphire instead of glass.

Generally, in order to obtain a transmittance of about 93 to 95% when the transmittance of glass (or PET or PMMA) as a transparent material is 91.6%, a plurality of high refractive index layers and low refractive layers are coated However, the transmittance of sapphire itself was 86%, which was 89.2% higher than the transmittance of sapphire itself. Blue light cuts were obtained at 380 nm and 450 nm The effect of having a blocking rate improved by about 3% was obtained.

When a sapphire liquid crystal protective sheet is manufactured using a transparent TPU, the UV cut rate is 99.7% at 350 nm and 62% at BLL at 380 nm, which is about 50% higher than 12% of the tempered glass liquid crystal protective sheet. At 450nm, the blue light cut rate is 12.4%, which is about 4% higher than the glass cut rate 8.9%. As a result, although the visible light transmittance of sapphire is 86% at 550 nm as a result, when the liquid crystal protective sheet is manufactured using TPU as a shatterproof film, the transmittance of 550 nm of the sapphire liquid crystal protective sheet, A liquid crystal protective sheet having a high transmittance of 90.1%, which is higher than the transmittance of the liquid crystal protective sheet.

The light transmittances of the conventional tempered glass liquid crystal protective sheet and the liquid crystal protective sheet using sapphire as listed above are summarized in Table 4 and Figs. 6A and 6B.

wavelength
Sapphire(%) Tempered glass liquid crystal
Protective (PET) Sapphire liquid crystal
Protection (PET) (%) Sapphire liquid crystal
Protection (TPU) (%) 250 nm 83.8 0.4 0.4 0.3 300 nm 84.7 0.3 0.3 0.6 350 nm 85.6 79.1 77.5 0.3 380 nm 85.6 88.0 85.2 37.5 450 nm 85.9 91.1 88.1 87.6 550 nm 86.0 91.2 89.2 90.1

As described above, the liquid crystal protection sheet using sapphire according to the embodiment of the present invention is characterized in that instead of the conventional tempered glass, sapphire monocrystals whose hardness is stronger than that of diamond are used, There is no life scratch, it has better heat dissipation than glass, and its chemical resistance is much stronger than glass, so it has high heat durability.

In addition, since the hardness is higher than that of glass, it is possible to manufacture a thin liquid crystal protective sheet, and the touch sensitivity is also high because the thickness is thin.

Furthermore, since the transmittance of sapphire itself has a transmittance of about 86% in the entire region of light (UV, visible light, and infrared rays), the UV cut rate is low and the visible light transmittance is low. On the other hand, As shown in Table 4, the sheet (TPU) had a UV cut rate of about 99.7% at 350 nm, a blue light interruption rate of 62.5% at a wavelength of 380 nm and a blue light interruption rate of 12.4% at 450 nm, It can reduce the harmful wavelength that can affect the human body.

In addition, the transmittance of sapphire itself is only 86% in the visible light region of 550nm. However, when the liquid crystal protective sheet is manufactured using PET and TPU as the anti-scattering film, the transmittance can be increased up to 89.2% and 90.1% , It is possible to obtain an effect of compensating a relatively low transmittance characteristic in the visible light region as compared with the tempered glass.

FIG. 7 illustrates a cross-sectional view of a liquid crystal protection sheet according to another embodiment of the present invention, illustrating a structure for increasing the transmittance by a refractive index. That is, the structure in which the adhesion layers 104 and 1042 corresponding to the low refractive index layer and the scattering layer 106 and 1062 corresponding to the high refractive index layer are stacked as shown in FIGS. 7A and 7B, A higher transmittance can be obtained. For reference, the functional thin film layer 110 may be additionally formed as shown in (b) in the structure of FIG. 7 (a). Basically, the process of manufacturing the liquid crystal protective sheet of the structure shown in Figs. 7A and 7B is the same as that of Figs. 2A and 2B except that the high adhesive layer and the anti-scattering layer are laminated in layers, .

 While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Substitutions, changes, and alterations without departing from the spirit and scope of the invention. Accordingly, the true scope of the present invention should be determined only by the appended claims.

Claims (8)

A sapphire sheet processed to fit the display panel size;
An ultra thin film anti-fouling coating layer formed on the upper surface of the sapphire sheet;
An anti-scattering film made of transparent thermoplastic polyurethane (TPU);
A low adhesive layer formed on the lower surface of the shrinkage preventing film by a low adhesive silicone coating;
And a high adhesion layer formed on the upper surface of the shrinkage preventing film by a high adhesion acrylic or a high adhesion silicone coating, wherein the high adhesion layer is formed by bonding the high adhesion layer to the lower surface of the sapphire sheet having the anti- Protective sheet. A sapphire sheet processed to fit the display panel size;
A functional thin film layer formed on a lower surface of the sapphire sheet;
An ultra thin film anti-fouling coating layer formed on an upper surface of the sapphire sheet;
An anti-scattering film made of transparent thermoplastic polyurethane (TPU);
And a high adhesion layer formed on each of the upper and lower surfaces of the anti-scattering film, and the high adhesion layer removed from the lower surface of the sapphire sheet including the functional thin film layer formed on the lower surface thereof And the liquid crystal protective sheet. A sapphire sheet processed to fit the display panel size;
An ultra thin film anti-fouling coating layer formed on the upper surface of the sapphire sheet by a wet coating method using a metal deposition or coating solution;
An anti-scattering film made of transparent thermoplastic polyurethane (TPU);
A functional thin film layer formed on an upper surface of the shrinkage preventing film;
A low adhesive layer formed by coating low adhesion silicone on a lower surface of the anti-scattering film on which the functional thin film layer is formed;
And a high adhesive layer formed by coating a high adhesive acrylic or a high adhesive silicone on the upper surface of the functional thin film layer,
Wherein the sapphire sheet is formed by laminating the high adhesive layer removed from the lower surface of the sapphire sheet. A sapphire sheet processed to fit the display panel size;
A first functional thin film layer formed on a lower surface of the sapphire sheet;
An ultra thin film anti-fouling coating layer formed on an upper surface of the sapphire sheet;
A second functional thin film layer formed on an upper surface of the anti-scattering film;
A low adhesive layer formed by coating low adhesion silicone on the lower surface of the anti-scattering film on which the second functional thin film layer is formed;
And a high adhesive layer formed by coating a high adhesive acrylic or a high adhesive silicone on the upper surface of the second functional thin film layer,
And the high adhesion layer removed from the lower surface of the sapphire sheet on which the first functional thin film layer is formed is removed. A sapphire sheet processed to fit the display panel size;
An ultra thin film anti-fouling coating layer formed on the upper surface of the sapphire sheet;
A low adhesion layer formed on the lower surface of the first anti-scattering film by a low adhesion silicone coating;
A first adhesive layer formed on the upper surface of the first anti-scattering film by a high adhesive acryl or a high adhesive silicone coating;
And a second adhesive layer formed on the upper surface of the second anti-scattering film by a high-adhesion acrylic or a high-adhesive silicone coating, wherein the lower surface of the sapphire sheet with the anti- Wherein the liquid crystal protective sheet is produced by laminating a second high adhesive layer and a first high adhesive layer. The liquid crystal protective sheet according to claim 5, further comprising a functional thin layer formed on a lower surface of the sapphire sheet. The liquid crystal protective sheet according to any one of claims 1 to 6, wherein the sapphire sheet is a sapphire single crystal having a light transmittance of 83% or more and a thickness of 0.05 mm to 0.5 mm. The liquid crystal protective sheet according to any one of claims 4 to 6, wherein the scattering-preventive film, the first anti-scattering film or the second anti-scattering film is PET or TPU.

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