KR100367960B1 - A method of manufacturing mold for barrier ribs replication of PDP rear panel by a new forming technology and fabrication - Google Patents

Abstract

The mold manufacturing method for forming a PDP (Plasma Display Panel) lower plate partition wall using a new processing technology and an assembly method proposed by the present invention first manufactures a core mold frame having a barrier ribs shape of a PDP lower plate. Then, by using a plastic injection molding a large volume of high-strength plastic molds of the unit volume size and precise assembly of them to produce a large-area precision mold for forming PDP lower plate bulkhead. PDP bottom plate is much simpler and cheaper than conventional methods such as screen printing and sand blasting by squeezing ceramic green sheet for PDP lower plate that is not completely dried with this mold. Can make bulkheads.

Description

A method of manufacturing mold for barrier ribs replication of PDP rear panel by a new forming technology and fabrication}

The present invention relates to a method for manufacturing a mold for forming a lower partition of a plasma display panel (hereinafter referred to as "PDP") using a new processing method and an assembling technique. Particularly, a fine partition can be manufactured to improve luminous efficiency of the PDP. The present invention relates to a mold manufacturing method for forming PDP lower plate bulkhead by using a new processing method and assembly technology that lowers production cost and strengthens product competitiveness in mass production.

PDP, a display that utilizes the characteristics of emitting fluorescent materials by ultraviolet rays, has been spotlighted as a wall-mounted TV that will lead the large-area display market in the future of flat panel displays (FPDs) that are rapidly developing. Based on the current level of technology and efficiency, the PDP is considered to be the most powerful as a 40 ″ to 60 ″ display. However, there are still some problems to be solved, such as excessively high price, improved luminance, and higher image quality.

In the PDP structure, barrier ribs are required to maintain the discharge distance and to prevent electrical and optical mutual interference between adjacent cells. In recent years, the width of the barrier ribs is becoming more and more fine (100 μm or less). The expansion of the discharge space according to the reduction of the partition width can improve the brightness and increase the discharge efficiency. Therefore, the formation of bulkheads accounted for the largest portion of the PDP process and emerged as the biggest obstacle to bottom plate production. Initially, thick film multi-layer printing method using screen printing method was used to form partition wall of PDP lower plate, but now, bulkhead structure is manufactured by spraying fine powder particles on PDP lower plate where protective film is patterned. Various methods are used, such as a sand blasting method, a squeezing method using a lift off method, and a FODEL method using a photosensitive glass that reacts with UV.

However, these methods have many technical problems that need to be improved in consideration of precision, manufacturing cost, and efficiency, and are evaluated in a way that is difficult to continuously apply to lower the price of PDP through mass production in the future. The most recent press molding method using a mold is to squeeze the bulkhead by pressing a ceramic green sheet, which is not completely dried, into a precision mold, thereby simplifying the bulkhead fabrication process of the PDP lower plate. It is attracting attention as the next generation technology that makes line width bulkhead easy to manufacture.

1A and 1B illustrate a method for manufacturing a PDP lower plate partition wall forming mold using a machining method in a conventionally attempted manner.

FIG. 1A illustrates a step of forming a mold 120 having a partition structure arranged at regular intervals by processing a metal plate with a die cutting machine 110, which is one of machining methods.

FIG. 1B illustrates a step of forming a PDP lower plate bulkhead structure 130 by pressing a mold 120 having the partition structure manufactured by the machining method onto a ceramic green sheet for PDP lower plate not completely dried. Shows.

However, this mold manufacturing method using the traditional machining method is difficult to manufacture precise molds due to difficulties such as machining limitations and cumulative errors, and the mold partition shape that can be manufactured under the machining method is limited to the vertical structure. It is difficult to release after pressing, and there are problems such as crack generation due to unevenness of molding pressure.

The present invention solves the technical problems of the existing PDP lower plate bulkhead manufacturing method using a new processing technology and precision assembly method and provides a new PDP lower plate manufacturing method that can be mass-produced at a low price.

The present invention proposes a method for manufacturing a precision mold for forming PDP lower plate partition walls using a novel processing technique and a precision assembly method capable of overcoming the processing limitations of the conventional machining method.

This new concept of machining, LIGA (abbreviation of German LIthographie, Galvanoformung, Abformung), is a technology that can collectively process molds and three-dimensional structures with submicron precision (less than 1 µm) using X-rays. It is a micro-processing technology that consists of three steps: photolithography process using electroplating, electroplating process and plastic molding process.

X-ray photolithography process is a process for producing a microstructure in the polymer photosensitive member by selectively irradiating and developing the X-ray to the polymer photosensitive member using an X-ray mask.

The electroplating process is a process of manufacturing a super-precision metal structure by selectively growing and filling a blank portion of the fine photoconductor structure, which is developed and produced by electroplating, by removing the polymer photoconductor.

Plastic molding process is a process to replicate a large number of plastic injection moldings having the same shape using the above-prepared ultra-precision metal structure as a core (mold).

1A and 1B illustrate a method for manufacturing a PDP lower plate bulkhead molding die using a machining method that has been conventionally tried.

2A to 2E are diagrams sequentially illustrating a method for manufacturing a mold for forming a PDP lower plate partition wall according to a first embodiment of the present invention.

3A to 3C are views sequentially illustrating a method of manufacturing a ceramic core mold for forming a PDP lower plate partition wall according to a second embodiment of the present invention.

The present invention is to produce a precision mold using a polymer photosensitive member structure that is selectively irradiated and then developed by X-ray, and a high-volume high-molecular plastic mold of a unit volume is produced using the precision mold as a core mold. And precisely assembling these to form a precision mold for PDP molding, and then pressing the ceramic green sheet which is not completely dried using the mold to form a partition structure of the PDP lower plate.

Such a method for manufacturing a PDP lower plate partition wall forming mold according to the present invention includes the steps of exposing the polymer photoconductor, developing the polymer photoconductor structure, forming a core mold using electroplating, plastic injection, assembly Comprising the step of pressing, the ceramic green sheet (ceramic green sheet) for the PDP lower plate.

In the step of exposing the polymer photoconductor, a polymer photoconductor is formed on the conductive substrate, and X-rays or ultraviolet rays of the radiation accelerator are selectively passed through a mask to be exposed to the polymer photoconductor.

The photoconductor selectively exposed to light (X-rays or ultraviolet rays) in the developing step of the polymer photoconductor structure is developed until the upper surface of the conductive substrate is exposed to produce a polymer photoconductor structure having a partition wall shape.

In the core mold forming step using electroplating, a core mold is formed by plating a metal from a conductive substrate which is a bottom surface of the manufactured polymer photoconductor structure.

In the plastic injection step, the high-mould plastic mold having a unit volume is injected in a large quantity using the manufactured core mold.

In the assembling step, the high-strength plastic molds of the unit volume manufactured are assembled and enlarged by using a self-assembly mechanism and a precision alignment rod.

The PDP lower plate bulkhead is formed by pressing the assembled PDP lower plate partition wall forming mold on the ceramic green sheet that is not completely dried in the pressing step of pressing the ceramic green sheet for PDP lower plate.

At this time, when the light source used in the step of exposing the photoreceptor is X-rays, the photoreceptor is characterized by using a PMMA sheet (sheet).

Next, a method for fabricating a PDP lower plate partition wall forming mold according to another feature of the present invention includes exposing a polymer photoconductor, forming a polymer photoconductor structure, forming a ceramic core mold, and plastic injection. , Assembling, pressing the ceramic green sheet for the PDP lower plate.

In the step of exposing the photoconductor, a polymer photoconductor is bonded onto the conductive substrate, and X-rays or ultraviolet rays are selectively passed through a mask to be exposed to the polymer photoconductor.

In the step of forming the polymer photoconductor structure, the photoconductor selectively exposed to X-rays is developed until the top surface of the bonded conductive substrate is exposed to produce a polymer photoconductor structure having a partition wall shape.

In the step of forming a ceramic core mold, a ceramic slurry or paste is filled in the fabricated photoconductor structure and dried and sintered to form a ceramic core mold for plastic injection.

In the step of plastic injection, a high-strength plastic mold having a unit volume is injected in a large quantity using the manufactured ceramic core mold.

In the assembling step, the prepared high-strength plastic injection molds of the unit volume are assembled by using a self-assembly mechanism and a precision rod to enlarge the size.

The PDP lower plate bulkhead is formed by pressing the assembled PDP lower plate partition wall forming mold on the ceramic green sheet that is not completely dried in the pressing step of pressing the ceramic green sheet for PDP lower plate.

Next, a method for manufacturing a PDP lower plate partition wall forming mold according to another feature of the present invention is to produce a core mold, plastic injection step, assembly step, ceramic green sheet for PDP lower plate (ceramic green sheet) Comprising the step of pressing.

In the step of manufacturing a core mold, a metal mold or a ceramic is machined to produce a core mold for plastic injection.

In the plastic injection step, a high-strength plastic mold having a unit volume is injected in a large quantity using the manufactured core mold.

In the assembling step, the prepared high-strength plastic injection molds of the unit volume are assembled by using a self-assembly mechanism and a precision rod to enlarge the size.

The PDP lower plate bulkhead is formed by pressing the assembled PDP lower plate partition wall forming mold on the ceramic green sheet that is not completely dried in the pressing step of pressing the ceramic green sheet for PDP lower plate.

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

2A to 2F are diagrams sequentially illustrating a method for manufacturing a mold for forming a PDP lower plate partition wall according to a first embodiment of the present invention.

As shown in Figures 2a to 2f, the mold manufacturing method for forming the PDP lower plate partition wall according to the first embodiment of the present invention is X-ray exposure step, photosensitive member development step, core metal mold forming step, plastic injection And a step of assembling, pressing the ceramic green sheet for the PDP lower plate to form a high-strength plastic mold using a core metal mold, and manufacturing the PDP lower plate bulkhead using the mold.

As shown in FIG. 2A, in the X-ray exposure step, a polymer photoconductor 220 reacting with X-rays is formed on the conductive substrate 210 to a predetermined thickness. Thereafter, X-rays selectively passing through the X-ray mask 230 reach the bottom of the polymer photoconductor 220 and are exposed so that a certain amount of energy is accumulated.

As shown in FIG. 2B, in the polymer photoconductor development step, the polymer photoconductor specimen selectively exposed to X-rays is immersed in a developer to develop a polymer photoconductor structure having a partition structure. When the development is completed, the portion selectively exposed by X-rays is etched by the developer until the top surface of the conductive substrate 210 is exposed to form a polymer photosensitive member structure having a partition structure.

As illustrated in FIG. 2C, in the core metal mold forming step, the bottom surface of the conductive substrate 210 exposed after etching in the previous step is activated using O ₂ plasma and a 10% sulfuric acid solution. The metal mold 250 is formed by plating a metal on the photoconductor structure by electroplating, polishing the upper portion of the grown plating layer 240, removing the polymer photoconductor, and separating the plated metal from the conductive substrate. At this time, the metal used for electroplating is nickel or a nickel alloy.

As shown in FIG. 2D, in the plastic injection step, the injection mold 270 is completed by combining the fabricated core metal mold 250 and the metal mold 260 by a machining method, and use the same to calculate a unit volume. The high-strength plastic molds 280 having a large quantity are injected. In this case, the high-strength plastic injection material used may be both a thermosetting resin and a thermoplastic resin having excellent strength, and the injection method may be both injection molding and transfer molding. As the thermosetting resin, an epoxy molding compound (EMC) containing a large amount of silica (85% to 95%) in epoxy or a phenol resin, an epoxy resin, or a melanin resin is used, and as a thermoplastic resin, a liquid crystal polymer (Liquid Crystal) is used. Polymer; LCP), polyphenylene sulfide (PPS), polycarbonate (PC), PEEK (product name), ULTEM (product name) and the like are used. The injected unit plastic mold includes a protrusion 290 and a receiving part 300 for assembling in the horizontal direction and includes a groove 310 into which the precision rod 320 can be fitted for assembling in the vertical direction. .

As shown in FIG. 2E, in the assembling step, the high-strength plastic injection molds 280 having the unit volume manufactured in the previous step are assembled using the protrusion 290 and the receiving part 300 of the mold in the horizontal direction and vertically. In the direction, the precision rod 320 is inserted into the groove 310 of the mold to be assembled to complete the large-area PDP lower plate partition wall forming mold 330.

As shown in FIG. 2F, the mold for forming the PDP lower plate partition wall formed in the previous step is pressed onto a ceramic green sheet 340 for lowering the PDP plate not completely dried to form the PDP lower plate partition wall. At this time, the crimping method to be used may be a cold press method or a crimping method using a laminator. Through this process, PDP lower plate bulkheads can be manufactured more simply and at a lower cost.

3A to 3C are diagrams for describing a second embodiment of the present invention, in which a core mold is manufactured by electroplating a polymer photosensitive member structure manufactured by X-ray exposure and development in the first embodiment. It is a process of forming a ceramic core mold by different methods.

A ceramic core mold is prepared by filling a ceramic slurry or paste 350 in the photosensitive member structure 340 manufactured by the process of FIGS. 2A and 2B, drying and sintering, and then applying a surface treatment. 360 is formed. At this time, the method of filling the ceramic slurry (ceramic slurry) may be simply poured into the general method or may be filled while the vacuum is extracted or pressure in the chamber. Hereinafter, a process of making a high-strength plastic mold by injection molding using a manufactured ceramic core mold and fabricating a PDP lower plate partition wall using the mold is the same as in the first embodiment.

The embodiments of the present invention described above are only one embodiment, and the present invention is not limited to the above examples, and of course, many modifications and variations are possible besides the above embodiments. For example, X-ray exposure and development process, electroplating process and core mold manufacturing using ceramic slurry and paste during core mold manufacturing, but not by core machining method A core mold can be manufactured. In addition, in order to increase the strength of the electroplating mold, alloy plating such as Ni-Fe and Ni-W may be applied, or TiN and Cr may be coated on the surface to reinforce the surface of the core mold and the high-strength plastic mold. By changing the partition shape of the core mold, it is possible to freely change the shape of the partition wall to facilitate separation of the mold and ceramic material during the partition forming process of the PDP lower plate or to increase the luminous efficiency of the PDP. . In order to convert the plastic mold into a metal mold, a large-area PDP mold of a metal is produced by coating a metal layer on a plastic mold enlarged by an assembly process and then performing an electroplating process.

As described above, the mold manufacturing method for forming PDP lower plate bulkhead according to the present invention is manufactured by assembling a high-strength plastic mold injected in a large quantity, so that mass production is possible at a low price, and the PDP lower plate bulkhead manufacturing method is also a crimping method using this mold. The overall PDP price can be significantly lowered by reducing the time and process involved in fabricating bottom plate bulkheads. In addition, the bulkhead shape of the precision mold for forming PDP lower plate bulkhead made of LIGA technology can be manufactured in various shapes and sizes according to its use and characteristics.The PDP made of this mold can improve luminous efficiency and brightness, and It is easy and can prevent the nonuniformity of molding pressure.

Claims (7)

Forming a polymer photoconductor on the conductive substrate and selectively exposing X-rays on the photoconductor through an X-ray mask; Developing the polymer photoconductor selectively exposed to X-rays until the top surface of the conductive substrate is exposed to form a photoconductor structure having a partition structure; Forming a core metal mold by filling a metal with electroplating on the polymer photoconductor structure; Injecting a high volume plastic mold of a unit volume in bulk using the core metal mold; Assembling the high-strength plastic molds to a large area; And Forming the PDP lower partition bulkhead by pressing the assembled large-area plastic mold onto the ceramic green plate for the lower panel not completely dried, thereby forming a PDP lower partition bulkhead structure. Mold making method for The method of claim 1, wherein the plastic injection material in the step of injecting a high volume plastic mold of the unit volume in a large amount is EMC, phenol resin, epoxy resin or melanin resin containing a large amount (85% to 95%) of silica components in epoxy PDP lower plate bulkhead using new processing technology and assembly method characterized by using thermosetting resin and thermoplastic resin such as Liquid Crystal Polymer, Polyphenylene Sulfide and Poly Carbonate Molding method for molding. The method of claim 1, wherein in the step of forming the PDP lower plate bulkhead structure by pressing the ceramic green plate for PDP lower plate, the pressing method uses a cold press method or a pressing method using a laminator. PDP lower plate bulkhead molding method using. The method of claim 1, wherein a ceramic slurry or paste is filled into the polymer photoconductor structure produced by the X-ray exposure and development process, dried, and sintered to form a ceramic core mold, which can be used as a core mold. Molding method for forming PDP lower plate bulkhead using new processing technology and assembly method. According to claim 1, instead of forming the core mold by X-ray photolithography process and electroplating process PDP lower plate bulkhead using a new processing technology and assembly method can be used to manufacture the core mold by a machining method Molding method for molding. According to claim 1, wherein the plastic mold of the unit volume produced by the injection process includes a protrusion and a receiving portion for horizontal assembly for assembly between the mold and having a groove into which a precision rod can be fitted for assembly in the vertical direction Method for producing a mold for forming PDP lower plate bulkhead using a new processing technology and assembly method. The method of claim 1, wherein a large PDP mold made of a metal is manufactured by coating a metal layer on the plastic mold enlarged by the assembly process and then performing an electroplating process. Manufacturing method for forming PDP lower plate bulkhead.