Patent Application
20130321996
The present invention relates to a method for manufacturing a bezel which is attached to a rim of a display panel and supports the display panel, and a bezel for display panels manufactured by the same, and more particularly, to a method for manufacturing a bezel for display panels using mold casting, which facilitates formation of a three-dimensional pattern while reducing unnecessary material costs.
“Bezels” refer to frames, chassis, and the like, which are used to support and/or receive various panels such as liquid crystal display panels, plasma display panels, and the like.
Generally, a liquid crystal display device, used as a display device for televisions, monitors for personal computers, mobile phones, and the like, includes a display panel and a bezel supporting and receiving the display panel.
Typically, such a bezel for liquid crystal display panels is manufactured by extruding an acrylic resin and removing a central portion of the resultant to form a planar frame.
However, in a typical method for manufacturing a bezel for display panels in the related art, a planar frame is prepared by removing a central portion of an acrylic plate, so that large amounts of the acrylic plate are cut and discarded, thereby causing increase in manufacturing costs.
In addition, since conventional bezels for display panels are manufactured by extruding acrylic resins, it is difficult to realize a three-dimensional pattern providing a sense of depth.
In the case of forming a three dimensional surface pattern through extrusion molding, there is a problem in that extrusion molding can only provide a relatively thin three-dimensional pattern due to bezel strength.
Moreover, in the case of forming a three dimensional surface pattern through injection molding, although a relatively thick three-dimensional pattern can be formed, it is difficult to provide large screen size due to mold deformation or mold separation.
It is an aspect of the present invention to provide a method for manufacturing a bezel for display panels, which can reduce material costs, prevent deformation of a three dimensional surface pattern, and facilitate mold separation.
It is another aspect of the present invention to provide a bezel for display panels in which a three dimensional surface pattern is formed using the method.
In accordance with one aspect of the present invention, a method for manufacturing a bezel for display panels includes: (a) preparing a lower mold, the lower mold being formed on a molding surface thereof with a three-dimensional pattern for imparting a surface shape to a bezel; (b) fastening a gasket to a rim of the molding surface of the lower mold; (c) fastening an upper mold to the gasket, the upper mold being formed with a raw-material injection port; (d) injecting a polymeric raw-material for the bezel through the raw-material injection port of the upper mold; and (e) curing the polymeric raw-material while transferring the three-dimensional pattern from the molding surface of the lower mold to the polymeric raw-material.
In accordance with another aspect of the present invention, a method for manufacturing a bezel for display panels includes: (a) preparing a lower mold, the lower mold being formed on a molding surface thereof with a three-dimensional pattern for imparting a surface shape to a bezel; (b) fastening a gasket to a rim of the molding surface of the lower mold; (c) injecting a polymeric raw-material for the bezel onto the molding surface of the lower mold; (d) fastening an upper mold to the gasket on the lower mold; and (e) curing the polymeric raw-material while transferring the three-dimensional pattern from the molding surface of the lower mold to the polymeric raw-material.
In accordance with a further aspect of the present invention, a method for manufacturing a bezel for display panels includes: (a) preparing a mold, the mold being formed on a molding surface thereof with a three-dimensional pattern for imparting a surface shape to a bezel; (b) fastening a gasket to a rim of the molding surface of the mold; (c) injecting a polymeric raw-material for the bezel onto the molding surface of the mold; and (d) curing the polymeric raw-material while transferring the three-dimensional pattern from the molding surface of the lower mold to the polymeric raw-material.
In accordance with yet another aspect of the present invention, a bezel for display panels includes: a substrate formed of a cured product of a resin composition, the substrate having a three-dimensional pattern on at least one surface thereof; and a glass film coated on the at least one surface of the substrate.
In a method for manufacturing a bezel for display panels according to embodiments, a bezel is manufactured by mold casting instead of extrusion, thereby reducing material costs.
In addition, in the method according to the embodiments, a three-dimensional pattern formed on a molding surface of a mold can be transferred to a cured product during curing inside a mold, thereby making it easy to impart the three-dimensional pattern to the surface of the bezel.
Further, in the method according to the embodiments, deformation of a mold can be prevented by attaching a frame formed of a material such as glass and the like, to an outer surface of a mold.
The above and other aspects, features, and advantages of the present invention will become apparent from the detailed description of the following embodiments in conjunction with the accompanying drawings. It should be understood that the present invention is not limited to the following embodiments and may be embodied in different ways, and that the embodiments are provided for complete disclosure and thorough understanding of the invention by those skilled in the art. The scope of the present invention is defined only by the claims. Like components will be denoted by like reference numerals throughout the specification.
Now, exemplary embodiments of the invention will be described in detail with reference to the accompanying drawings.
Referring to
In operation (S110) of preparing a lower mold, a lower mold formed on a molding surface thereof with a three-dimensional pattern for imparting a surface shape to a bezel is prepared.
Preferably, the lower mold 210 is formed of a material such as a metal, Teflon, rubber, and the like, which allow easy formation of the three-dimensional pattern thereon. More preferably, the lower mold 20 is formed of stainless steel exhibiting excellent corrosion resistance and strength.
As shown in
However, these materials are vulnerable to bending and can cause deformation of the mold when used alone.
To prevent such a problem, a frame 310 formed of a material such as a glass plate, a metal honeycomb plate and the like may be attached to an outer surface of the mold, as shown in
The three-dimensional pattern formed on the molding surface 215 of the lower mold 210 may be formed by various methods, such as NC (numerical control) machining, chemical etching, stamping, and the like.
The thickness of the three-dimensional pattern to be formed on the surface of the bezel is determined depending on the three-dimensional pattern on the molding surface 215 of the lower mold 210. Therefore, when the three-dimensional pattern is formed to a thickness of 1 mm or more on the molding surface 215 of the lower mold 210, the three-dimensional pattern may also be formed to a thickness of 1 mm or more on the surface of the bezel.
The molding surface 215 of the lower mold 210 may be coated with a release agent to a thickness of about 2 μm to facilitate mold separation.
Next, in operation S210 of fastening a gasket, the gasket is fastened to a rim of the molding surface of the lower mold.
The gasket 220 forms a seal between the upper mold and lower mold, and the thickness of a molded article is determined depending on the thickness of the gasket 220. In addition, the gasket 220 may be prepared from a material, such as silicones rubbers, and the like.
Next, in operation (S130) of fastening an upper mold, the upper mold having a raw-material injection port is fastened to the gasket on the lower mold.
The upper mold may have a planar shape or a three-dimensional pattern on a molding surface thereof.
As shown in
As shown in
As shown in
Advantageously, each of the upper mold 410 and the lower mold 210 has a thickness of 3 mm to 20 mm If the thickness of each of the upper mold 410 and the lower mold 210 is below 3 mm, the upper and lower molds can be bent. On the contrary, if the thicknesses of the upper mold 410 and the lower mold 210 exceeds 20 mm, it is difficult to handle the upper and lower molds.
Next, in operation (S140) of injecting a raw material, the raw material for the bezel is injected onto the molding surface of the lower mold via the raw-material injection port of the upper mold. The raw-material injection port may have a hole or slit shape penetrating the upper mold.
Injection of the raw material may be performed at room, namely, about 18° C. to about 25° C.
The raw material may be a thermosetting resin composition.
Examples of the resin composition may include acrylic resins, polycarbonate resins, ABS resin, polyurethane resins, olefin resins, epoxy resins, melamine resins, unsaturated polyester resins, and the like.
These resins may be used alone or in combination thereof. In addition, the resin composition may further include alumina trihydrate (ATH) and the like as fillers.
Depending on colors and physical properties of the bezel for display panels, the resin composition may be prepared from these resins.
For example, when manufacturing a transparent bezel for display panels, a resin composition including methyl methacrylate (MMA) and alumina trihydrate (ATH) as main components may be used as the raw material. In this case, the resin composition may have a viscosity of 300 cPs to 500 cPs. Within this range, injection molding of the resin composition can be easily performed. If the viscosity of the resin composition is less than 300 cPs, curing time can increase and a molded article can have insufficient density. On the contrary, if the viscosity of the resin composition exceeds 500 cPs, injection molding of the resin composition becomes difficult.
In addition, the raw material may further include pearls, pigments, chips, and the like to impart design effects to the bezel.
Next, in operation (S150) of curing/transferring a three-dimensional pattern, the raw material injected onto the molding surface of the lower mold is cured using a heat curing method. Methods for heat curing are not specifically limited. As shown in
Next, in operation (S160) of heat treatment, some of the raw material, unreacted in operation of curing/transferring a three-dimensional pattern, may be further cured through heat treatment.
That is, in operation of heat treatment, monomers and other components unreacted during curing are further cured, thereby completing curing the bezel for display panels.
Since this operation is performed to further cure the monomers and other components unreacted during curing, this process is performed using steam at 100° C. or more, more preferably at about 100° C. to 200° C.
Duration for operation (S150) of curing/transferring a three-dimensional pattern and for operation (S160) of heat treatment may vary depending on the raw material. For example, when a resin composition including methyl methacrylate (MMA) as a main component is used as the raw material to prepare a transparent bezel for display panels, curing and heat treatment may be performed for about 3 hours and for about 2 hours, respectively. On the contrary, when a resin composition including methyl methacrylate (MMA) and alumina trihydrate (ATH) as main components is used as the raw material to prepare a white bezel for display panels, curing and heat treatment may be carried out for about 1 hour to about 2 hours and for about 30 minutes to 1 hour, respectively.
Then, the upper mold and the lower mold are separated from the bezel for display panels.
Next, in operation (S170) of coating a glass film, at least one surface of the bezel formed of a cured polymeric raw material is coated with the glass film, wherein the at least one surface has a transferred three-dimensional pattern.
The glass film performs a function of protecting the surface of the bezel and a function of retaining an outer appearance of the bezel.
The glass film may be formed of glass paints, inorganic coating solutions, or coating solutions including polysilazanes.
In the method for manufacturing a bezel for display panels according to the embodiment, the glass film may be prepared using a coating solution containing a polysilazane.
The polysilazane is a polymer having repeated Si-N (silicon-nitrogen) bonds, and any polymer allowing easy conversion into silica can be used without limitation. Generally, a Si—N (silicon-nitrogen) bond includes a silicon atom bonded with two hydrogen atoms, and is readily converted into silica.
Polysilazanes may have molecular structures such as a straight chain structure, a branched straight chain structure, a branch structure, a ring structure, a cross-linking structure, or a combination thereof. These polysilazanes may be used alone or in combination thereof. As representative examples of these polysilazanes, there are polymers including repeated silazane units represented by Formula 1. It should be noted that the polymers include an oligomer.
wherein R1, R2, and R3 are a hydrogen atom or a C1-C8 alkyl group, such as a methyl group, an ethyl group, a propyl group, and a butyl group.
To facilitate conversion into silica, the polysilazane preferably includes repeated units in which both R1 and R2 are hydrogen atoms, and more preferably, repeated units in which all of R1, R2 and R3 are hydrogen atoms.
When all of R1, R2 and R3 are hydrogen atoms, the polysilazane has repeated units represented by Formula 2, and is called perhydropolysilazane.
Perhydropolysilazane includes chemical structure moieties represented by Formula 3:
Some hydrogen atoms bonded to silicon atoms in the perhydropolysilazane may be substituted by hydroxyl groups.
After obtaining adducts through reaction between dihydrogendichlorosilane and an organic base (for example, pyridine or picoline), the perhydropolysilazane may be easily obtained by reacting the adducts with ammonia.
The polysilazane, particularly, perhydropolysilazane generally has a number-average molecular weight of 100 to 50,000, preferably 200 to 2,500 in consideration of volatility and solubility.
The polysilazane, particularly, perhydropolysilazane, which is included in the glass film of the bezel according to the embodiment, may include a small amount of silica conversion accelerating catalyst.
Examples of the silica conversion accelerating catalyst may include organic amine compounds, organic acids, inorganic acids, carboxylic acid metallic salts, and organo-metallic complex salts.
Particularly, organic amine compounds are preferred, and examples of organic amine compounds may include nitrogen-containing cyclic organic amines, such as 1-methylpiperazine, 1-methylpiperizine, 4,4′-trimethylenedipiperizine, 4,4′-trimethylenebis(1 -methylpiperizine), diazabicyclo-[2,2,2]octane, cis-2,6-dimethylpiperazine, 4-(4-methylperizine)pyridine, pyrizine, dipyridine, α-picoline, β-picoline, γ-picoline, piperizine, lutidine, pyrimidine, pyridazine, 4,4′-trimethylenedipyridine, 2-(methylamino)pyrizine, pyrazine, quinoline, quinoxaline, triazine, pyrrole, 3-pyrroline, imidazole, triazole, tetrazole, 1-methylpyrrolidine, and the like; aliphatic or aromatic amines, such as methylamine, dimethylamine, trimethylamine, ethyamine, diethyamine, triethylamine, propylamine, dipropylamine, tripropylamine, butylamine, dibutylamine, tributylamine, pentylamine, dipentylamine, tripentylamine, hexylamine, dihexylamine, trihexylamine, heptylamine, diheptylamine, octylamine, dioctylamine, trioctylamine, phenylamine, diphenylamine, triphenylamine, and the like; DBU(1,8-diazabicyclo[5,4,0]7-undecene), DBN(1,5-diazabicyclo[4,3,0]5-nonene), 1,5,9-triazacyclododecane, and 1,4,7-triazacyclononane.
The silica conversion accelerating catalyst may be present in an amount of 0.1% by weight (wt %) to 10 wt % in a total weight of the polysilazine, particularly, perhydropolysilazane.
By coating the surface of the bezel for display panels according to the invention with a polysilazane solution, a highly dense film may be formed on the surface of the bezel. In addition, the bezel according to the invention has outstanding properties in terms of corrosion resistance, abrasion resistance, antifouling, ease of cleaning, wettability, sealing effects, chemical resistance, oxidation resistance, physical barrier effects, heat resistance, fire resistance, low shrinkage, smoothing effects, durability, antistatic properties, scratch resistance, and the like.
Any coating method may be used without limitation to coat the surface of the bezel with the glass film. Advantageously, spray coating, dip coating, spin coating, and the like may be used.
Referring to
In operation (S510) of preparing a lower mold, the lower mold formed on a molding surface thereof with a three-dimensional pattern for imparting a surface shape to the bezel is prepared. In operation (S520) of fastening a gasket, the gasket is fastened to a rim of the molding surface of the lower mold.
In operation (S530) of injecting a raw material, the raw material for the bezel is injected onto the molding surface of the lower mold. In operation (S540) of fastening an upper mold, the upper mold is fastened to the gasket on the lower mold.
In operation (S550) of curing/transferring a three-dimensional pattern, the injected raw material is thermally cured, while transferring the three-dimensional pattern from the molding surface of the lower mold to a cured product of the raw material. In operation (S560) of heat treatment, monomers and other components unreacted during curing are further cured.
In operation (S570) of coating a glass film, at least one surface of the bezel formed of a cured polymeric raw material is coated with the glass film, wherein the at least one surface has a transferred three-dimensional pattern.
As shown in
As shown in
In the embodiments shown in
However, it should be understood that the present invention is not limited to the embodiments shown in
Referring to
The method may further include coating a glass film (S640). In operation (S610) of preparing a mold, a mold formed on a molding surface thereof with a three-dimensional pattern for imparting a surface shape to the bezel is prepared.
In operation (S620) of fastening a gasket, the gasket is fastened to a rim of the molding surface of the mold.
In operation (S630) of injecting a raw material, the raw material for the bezel is injected onto the molding surface of the mold. The raw material may be a resin composition curable by heat, light or electron beam.
In operation (S640) of curing/transferring a three-dimensional pattern, the injected raw material is cured while transferring the three-dimensional pattern from the molding surface of the mold to a cured product of the raw material. In this case, various curing processes may be applied depending on which raw materials employed.
For example, when using a thermosetting resin composition as the raw material, heat curing may be used. On the other hand, when using an ultraviolet curable resin composition as the raw material, ultraviolet curing may be carried out.
In operation (S650) of coating a glass film, at least one surface of the bezel formed of a cured polymeric raw material is coated with the glass film, in which the at least one surface has a transferred three-dimensional pattern.
A bezel for display panels manufactured by the method according to embodiments of the invention facilitates formation of a three-dimensional pattern on a surface thereof while reducing unnecessary material costs.
The bezel for display panels includes: a substrate formed of a cured product of a resin composition, the substrate having a three-dimensional pattern on at least one surface thereof; and a glass film coated on the at least one surface of the substrate.
The bezel may be formed to have a transparent color or a white color depending on which raw materials are employed.
Particularly, the three-dimensional pattern may be formed to have a thickness of 1 mm or more on a surface of the bezel. As described above, this can be achieved using metals, and the like having properties for easy formation of patterns as a material for a mold, and applying NC machining, and the like to a molding surface of the mold, and as a result, by forming a three-dimensional pattern having a thickness of 1 mm or more on the mold.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2011-0056663 | Jun 2011 | KR | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/KR12/04520 | 6/8/2012 | WO | 00 | 8/23/2013 |
