KR20180030316A - Glass fiber fabric/polymer transparent complex sheet and manufacturing method thereof - Google Patents

Abstract

Disclosed by the present invention is a transparent complex sheet including: a glass fiber woven body in which a plurality of glass fibers are woven; and a transparent polymer layer which is combined with the glass fiber woven body by being laminated on the upper part or the lower part of the glass fiber woven body. The disclosure of the present invention also relates to a transparent complex sheet manufacturing method which includes: a step of primarily heating and compressing the glass fiber woven body in which a plurality of glass fibers are woven; a step of chemically reinforcing the primarily heated and compressed glass fiber woven body; and a step of forming the transparent complex sheet by laminating the chemically reinforced glass fiber woven body with the transparent polymer layer manufactured by a common thick film process such as tape casting. By the above, the transparent complex sheet by the present invention can achieve low price with formability, impact resistance, design flexibility, and processing flexibility which are advantages of existing plastic substrates as well as can greatly improve abrasion resistance and strength. The present invention also has less concern about having the torsion of a substrate caused by the temperature added to the following processing of the substrate unlike existing technology.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a glass fiber woven fabric / polymer transparent composite sheet,

More particularly, the present invention relates to a transparent composite sheet, and more particularly, to a transparent composite sheet, which is formed by stacking a glass fiber woven fabric and a polymer in a laminated structure, thereby achieving not only a remarkable improvement in abrasion resistance and strength but also a flexibilty, Glass fiber woven fabric / polymer transparent composite sheet.

The present invention also relates to a method for producing the transparent composite sheet.

Generally, a glass substrate is used as a cover or an exterior material of a display device, a mobile phone, or the like.

Especially, recently, a tempered glass substrate called so-called gorilla glass has recently been used, but it is excellent in abrasion resistance, but instead has a drawback in that it is weak to impact, heavy, and non-flexible. For example, when such a glass substrate drops a cell phone used as a window and impacts even a part of the glass substrate, cracks propagate as a whole, and the entire glass substrate must eventually be replaced.

On the other hand, a method of replacing such a glass substrate with a monocrystalline sapphire substrate and using it as a window of a mobile phone, for example, is under investigation. However, since such a sapphire window is also a weak ceramic for shock, It is fragile throughout.

Accordingly, polymer-based covers or sheathing materials are considered as an alternative. Replacing the glass substrate with such a plastic substrate can provide a light weight, flexibility, design flexibility, excellent impact resistance, excellent moldability, and low cost. As an example, Japanese Unexamined Patent Publication No. 6-337408 entitled "Transparent Resin Substrate for Liquid Crystal Display Device" (published on December 6, 1994) cures an epoxy resin composition comprising an epoxy resin, an acid anhydride- To produce a substrate.

However, the plastic substrate has a problem that scratches are liable to occur due to lack of abrasion resistance, among other things.

As a solution to this problem, there has been studied a technique for producing a composite plastic substrate by adding an inorganic filler such as glass fiber to the polymer. As an example, Japanese Patent Application Laid-Open No. 2004-151291 entitled " Plastic Substrate for Display Device "(published on May 27, 2004) or Japanese Patent Laid-open Publication No. 2013-28776 And then the resin is impregnated and cured to produce a composite sheet substrate. As another example, in Korean Patent Laid-Open No. 10-2008-0105834 entitled " Method of producing transparent plastic film "(published on December 4, 2008), glass flake particles are mixed in a polymer solution, . ≪ / RTI >

However, it is difficult to uniformly disperse the inorganic filler such as glass fiber into the polymer material once the above-mentioned composite is formed. In addition, in order to prevent twisting of the substrate due to a temperature applied in a subsequent process (for example, electrode layer deposition on a substrate) of a composite plastic substrate, the coefficient of linear expansion must be low. In order to lower the coefficient of linear expansion, The filler must be contained in a large amount. However, this leads to a problem that it is difficult to reduce the weight of the plastic substrate and the plastic substrate must be thick.

In order to solve the above-mentioned problems, the present invention is to provide a transparent composite sheet which has the advantages of the above-described conventional plastic substrate, but which has greatly improved abrasion resistance and strength.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a transparent composite sheet comprising a glass fiber woven fabric in which a plurality of glass fibers are woven, and a transparent polymer layer laminated and bonded to the glass fiber woven fabric.

The diameter of the glass fibers may range from 5 to 100 mu m. The composition of the glass fiber may be sodalime glass.

The composition of the transparent polymer layer may be selected from the group consisting of Bisphenol Z epoxy, Trifunctional Acrylate, Hydroxy-cyclohexyl-phenyl-ketone and Iodonium Iodonium hexafluorophosphate, and preferably a mixture of bisphenol Z epoxy mixed with an equivalent ratio of 2: 1 and trifunctional acrylate.

Further, the refractive index difference between the glass fiber woven fabric and the transparent polymer layer may be 0.005 or less, and the transparent composite sheet may have a light transmittance of 60% or more at a wavelength of 550 nm.

According to another aspect of the present invention, there is provided a method for producing a transparent composite sheet, the method comprising: a first heat-press bonding of a glass fiber weave having a plurality of glass fibers woven thereon; And laminating the chemically reinforced glass fiber woven body with a transparent polymer layer to form a transparent composite sheet.

The first heating and pressing may apply the first pressure at a first temperature higher than the softening point of the glass fiber. Preferably, the first temperature is in a range of 650 ° C or higher and the first pressure is 2 To 20 MPa.

Further, the first temperature and the first pressure may be adjusted to change at least one of the surface roughness and the pore size of the glass fiber weave.

Also, the step of chemically strengthening may comprise dipping the glass fiber weave into a KNO ₃ melt. Also, the chemical strengthening may be performed at a temperature in the range of 400 to 450 ° C. for 3 to 11 hours, and preferably the chemical strengthening may be performed at a temperature in the range of 400 to 450 ° C. for less than 7 hours have.

In addition, the step of forming a transparent composite sheet by laminating the transparent polymer layer with the transparent polymer layer may be performed by second heat-pressing a transparent polymer film on the glass fiber weave body. Preferably, the second hot pressing may be performed by applying a pressure ranging from 10 to 50 MPa at a temperature in the range of 150 to 200 ° C.

The step of forming a transparent composite sheet by laminating with the transparent polymer layer may include coating a transparent polymer on the surface of the glass fiber weave.

In addition, the transmittance of the transparent composite sheet can be controlled by changing the size of the glass fiber.

In addition, each of the plurality of glass fibers may be formed of glass fibers of a strand unit, and may be woven to constitute the glass fiber weave body.

The transparent composite sheet according to the present invention is characterized in that a glass fiber woven fabric and a polymer are laminated and bonded to each other so that abrasion resistance and strength are greatly improved and a low price is achieved by having flexibility, design flexibility, impact resistance, Can be achieved. In addition, unlike the prior art, it is advantageous that there is less possibility of twisting of the substrate due to the temperature applied in the processing process of the substrate in the future.

1 is a schematic structural view of a glass fiber woven fabric / polymer transparent composite sheet according to the present invention.
Fig. 2 is a flow chart for explaining a method of producing a glass fiber woven fabric / polymer transparent composite sheet according to the present invention.
3A to 3C are schematic views for explaining a heating and pressing step of a glass fiber weave body in the present invention. Fig. 3A shows a glass fiber weave body woven in the warp yarns 12 and weft yarns 14 in one- FIGS. 3B and 3C show a glass fiber weave body in which such a woven fabric is heated and pressed to adjust the surface roughness and pore size of the woven fabric.
4 is a graph showing the compressive stress ("Compressive Stress") according to the chemical strengthening time ("hrs") and the temperature ("Tempering Temperature") of the glass fiber woven / polymer transparent composite sheet 100 prepared in one embodiment of the present invention. ). ≪ / RTI >
5 is a graph showing changes in flexural strength ("Flexural Strength") according to chemical strengthening time ("hrs") and temperature ("Tempering Temperature") of the glass fiber weave / polymer transparent composite sheet 100 of FIG. to be.
FIG. 6 is a graph showing the change in transmittance ("Transmission") according to a change in the size ("Size of Fiber") (5 to 70 μm) of the glass fiber weave 10 And the transmittance change of the glass fiber weave / polymer transparent composite sheet (100: " Glass fabric coated polymer ") of Fig.

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic structural view of a glass fiber woven fabric / polymer transparent composite sheet according to the present invention, and FIG. 2 is a flowchart for explaining a manufacturing method of a glass fiber woven fabric / polymer transparent composite sheet according to the present invention.

1, in the present invention, instead of impregnating an inorganic filler made of glass fiber into a polymer resin to fabricate a plastic substrate, a glass fiber woven fabric 10 in which glass fibers are woven is made into a transparent polymer layer 20 And a laminated glass fiber woven fabric / polymer transparent composite sheet 100 are prepared. Thus, the polymer layer 20 is laminated and laminated on the glass fiber layer 10.

In particular, according to the present invention, the glass fiber fabric 10 is woven in a strand unit (S201), which is heated and pressed to adjust the surface roughness and pore of the woven fabric (S202), and the strength of the glass is increased by chemical strengthening (S203).

The glass fiber woven fabric / polymer transparent composite sheet 100 according to the present invention in which the polymer layer 20 is laminated on the surface of the glass fiber weave body 10 is formed by the polymer layer 20, The destruction due to the impact caused by the external impact is generated only by a single unit of glass fibers inside the glass fiber weave body 10, so that the front surface destruction due to the crack propagation does not occur, Destruction is only localized.

3A to 3C are schematic views for explaining a heating and pressing step of a glass fiber weave body in the present invention. Fig. 3A shows a glass fiber weave body woven in the warp yarns 12 and weft yarns 14 in one- FIGS. 3B and 3C show a glass fiber weave body in which such a woven fabric is heated and pressed to adjust the surface roughness and pore size of the woven fabric.

In the present invention, the diameter of the glass fibers constituting the glass fiber woven fabric 10 is 5 to 200 占 퐉, preferably 5 to 100 占 퐉, and more preferably 5 to 10 占 퐉. As the glass fiber, a known glass composition such as E glass, C glass, A glass, S glass, D glass, NE glass, T glass and the like can be used, and preferably, soda lime glass can be used.

Also, in the present invention, the surface roughness and the pore size of the woven fabric can be controlled by controlling the applied temperature and pressure according to the degree of permeability and texture level required as the window or the sheathing material during the hot pressing . The glass fiber woven fabric / polymer transparent composite sheet 100 of the present invention has a preferable transmittance range of about 80% or more for a window wavelength of 550 nm, or about 60% or more for a casing. Also, in the present invention, the allowable refractive index range between the glass fiber weave body 10 and the polymer layer 20 is about 0.005 or less. In one embodiment, the refractive index of the glass fiber weave body 10 is about 1.58. In one embodiment of the present invention, the hot pressing process may be performed at a temperature in the range of about 650 DEG C or more, which is higher than the softening point of the glass at a pressure ranging from 2 to 20 MPa, for several minutes, preferably one minute. By adjusting the applied pressure and temperature, the illuminance and pore size can be adjusted differently as shown in FIGS. 3B and 3C, respectively.

Then, the glass fiber woven fabric 10 heated and pressed as described above is chemically reinforced to increase the strength (S203). By such chemical strengthening, a part of sodium ion (Na ⁺ ) on the glass surface is replaced with potassium ion (K ⁺ ) having a larger ion radius at a temperature higher than the glass transition temperature to form a compressive stress layer on the surface to increase the strength. In one embodiment of the present invention, KNO ₃ is added in the temperature range of 400 ° C or higher, preferably 400 to 450 ° C for 3 to 11 hours, preferably 3 to 7 hours. Dipping the hot-pressing a glass fiber woven material (10) as above, the melt can be carried out by the chemical strengthening and a portion of the Na ⁺ ions of the glass fiber surface ionic radius lead to a relatively larger ion exchange with K ⁺ ions.

The composition of the transparent polymer layer 20 according to the present invention may be selected from the group consisting of Bisphenol Z epoxy, Trifunctional Acrylate, Hydroxy-cyclohexyl-phenyl- ketone, and iodonium hexafluorophosphate. In order to increase the transmittance of the transparent composite sheet 100, the refractive index of the glass fiber woven fabric 10 may be equal to or higher than that of the glass fiber woven fabric 10 It is preferable to select a composition having a refractive index. A preferred polymer layer 20 composition in the present invention is a mixture of bisphenol Z epoxy and trifunctional acrylate with an equivalent ratio of 2: 1.

The transparent polymer layer 20 may be formed into a film by a conventional method such as tape casting and heat-pressed to the glass fiber woven fabric 10 (in one embodiment, at a temperature of about 150 to 200 DEG C and at a pressure of about 10 to 50 MPa The glass fiber woven fabric / polymer transparent composite sheet 100 having the structure shown in Fig. 1 can be formed by directly coating the glass fiber woven fabric 10 without heating or pressing.

In the glass fiber woven fabric / polymer transparent composite sheet (100), the thickness of the glass fiber weave body (10) may range from 7 to 200 μm, and the thickness of the polymer layer (20) 1 mm, and in the case of exterior materials, it may be in the range of 0.1 mm or more. Generally, the glass fiber weave body 10 can be joined to the polymer layer 20 as a single layer.

4 is a graph showing the compressive stress ("Compressive Stress") according to the chemical strengthening time ("hrs") and the temperature ("Tempering Temperature") of the glass fiber woven / polymer transparent composite sheet 100 prepared in one embodiment of the present invention. ). ≪ / RTI >

The glass fiber composition used in this embodiment is soda lime glass and the polymer composition used is a mixture of bisphenol Z epoxy and trifunctional acrylate with an equivalent ratio of 2: 1. The mixture can be made into a glass fiber woven fabric / polymer transparent composite sheet 100 by tape casting to form a polymer film, and then heating and pressing to a surface of the glass fiber weave body 10 at 170 ° C. . And, the compressive stress can be measured according to the ISO-178 test standard, and a measuring instrument such as a universal testing machine (4202, Instron, USA) can be used.

4, the highest compressive stress was measured at 420 ° C, and the highest compressive stress was found to be about 720 MPa when chemical strengthening was performed for 5 hours as a whole. Compressive stress in chemical strengthening over 7 hours tends to decrease.

5 is a graph showing changes in flexural strength ("Flexural Strength") according to chemical strengthening time ("hrs") and temperature ("Tempering Temperature") of the glass fiber weave / polymer transparent composite sheet 100 of FIG. to be. The bending strength can be measured according to the ISO-4049 test standard and the equipment described above with reference to Fig. 4 can be used as an example of the measuring equipment.

5, the overall tendency of the bending strength is similar to the compressive stress of FIG. 4, and it is the highest at 375 MPa when chemical strengthening is performed at 420 DEG C for 5 hours. Also, when chemical strengthening exceeds 7 hours, the bending strength tends to decrease as in the compressive stress of FIG.

FIG. 6 is a graph showing a change in transmittance ("Transmission") according to a change in the size ("Size of Fiber") of glass fiber (5 to 70 μm) ) And the transmittance change of the glass fiber weave / polymer transparent composite sheet (100: " Glass fabric coated polymer ") of Fig. The transmittance can be measured using a UV-cis-NIR spectrometer (JASCO, V570) as a measuring device under the condition of 550 nm of visible light wavelength.

6, in the case of a glass fiber weave, the glass fiber exhibits the lowest transmittance at about 84% when the glass fiber diameter is about 5 μm, and the highest transmittance at about 50 μm to 90% . This is because the diameter of the glass fiber at the time of hot pressing shows the boundary scattering effect. On the other hand, in the case of a glass fabric coated polymer sheet, the transmittance is reduced compared to a glass fiber fabric ("Glass fabric"), but the difference is small It can be seen that the refractive index control between the glass fiber and the polymer is good.

As described above, according to the present invention, the glass fiber weave structure 10 is laminated with the polymer layer 20, and the glass fiber fabric 10 is made of glass fibers in a strand unit, And the strength of the glass is increased.

In the glass fiber weave / polymer transparent composite sheet 100 according to the present invention, the abrasion resistance of the surface is improved due to the polymer layer 20, and in particular, Since the crack is generated only by the unit glass fibers, the fracture is limited only to the impact point without occurrence of the front fracture by the crack propagation.

In addition, unlike the prior art, the glass fiber woven fabric / polymer transparent composite sheet 100 according to the present invention can be produced by laminating a glass fiber weave material on a polymer layer without surface dispersion of the glass fiber into a polymer material The linear expansion due to its temperature follows the linear expansion of the polymer layer 20. [ Thus, unlike the prior art, it is also advantageous that there is less risk of twisting of the substrate due to the temperature applied in later processing steps (e.g., electrode layer deposition onto the substrate).

Therefore, the transparent composite sheet 100 according to the present invention can achieve not only the abrasion resistance and the strength are greatly improved, but also the flexibility, the design flexibility, the impact resistance and the moldability, which are advantages of the conventional plastic substrate, .

The various characteristics of the preferred embodiments of the present invention described above may vary somewhat within a conventional error range depending on the powder characteristics such as the average particle size, distribution and specific surface area of the composition powder, and the purity of the raw material, Is quite natural for those of ordinary skill in the art.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. , Additions and the like are to be regarded as belonging to the claims.

Claims (19)

A glass fiber weave body in which a plurality of glass fibers are woven;
And a transparent polymer layer laminated and bonded to the glass fiber weave body. The method according to claim 1,
Wherein the glass fiber has a diameter ranging from 5 to 100 mu m. The method according to claim 1,
Wherein the glass fiber has a composition of soda lime glass. The method according to claim 1,
The composition of the transparent polymer layer is selected from the group consisting of Bisphenol Z epoxy, Trifunctional Acrylate, Hydroxy-cyclohexyl-phenyl-ketone and Iodonium hexafluoro Wherein the transparent composite sheet is at least one selected from the group consisting of iodonium hexafluorophosphate. The method according to claim 1,
Wherein the composition of the transparent polymer layer is a mixture of a bisphenol Z epoxy having an equivalent ratio of 2: 1 and a trifunctional acrylate. The method according to claim 1,
Wherein the refractive index difference between the glass fiber woven fabric and the transparent polymer layer is 0.005 or less. The method according to claim 1,
Wherein the transparent composite sheet has a light transmittance of at least 60% at a wavelength of 550 nm. A method for producing a glass fiber weave body, comprising the steps of: heating a glass fiber weave body having a plurality of glass fibers woven thereon;
Chemically reinforcing the first heat-pressed glass fiber weave body;
And laminating the chemically reinforced glass fiber woven fabric with a transparent polymer layer to form a transparent composite sheet. 9. The method of claim 8,
Wherein the first pressure bonding step applies a first pressure at a first temperature higher than the softening point of the glass fiber. 10. The method of claim 9,
Wherein the first temperature is in the range of 650 ° C or more and the first pressure is in the range of 2 to 20 MPa. 10. The method of claim 9,
Wherein the first temperature and the first pressure are adjusted to change at least one of a surface roughness and a pore size of the glass fiber weave body. 9. The method of claim 8,
Wherein the chemical strengthening step comprises dipping the glass fiber weave into a KNO ₃ melt. 13. The method of claim 12,
Wherein the chemical strengthening step is performed at a temperature ranging from 400 to 450 DEG C for 3 to 11 hours. 13. The method of claim 12,
Wherein the chemical strengthening step is performed for less than 7 hours at a temperature ranging from 400 to 450 < 0 > C. 9. The method of claim 8,
Wherein the step of forming a transparent composite sheet by laminating the transparent polymer layer with the transparent polymer layer is carried out by subjecting the transparent polymer film to a second heat press bonding to the glass fiber weave body. 16. The method of claim 15,
Wherein the second hot pressing is performed by applying a pressure in a range of 10 to 50 MPa at a temperature in the range of 150 to 200 ° C. 9. The method of claim 8,
Wherein the step of forming a transparent composite sheet by laminating with the transparent polymer layer comprises coating a transparent polymer on the surface of the glass fiber woven fabric. 9. The method of claim 8,
Wherein a transmittance of the transparent composite sheet is controlled by changing a diameter of the glass fiber. 9. The method of claim 8,
Wherein the plurality of glass fibers are respectively made of glass fibers in a strand unit and are woven.

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