JP2006198713A - Powder for shot blast - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide metal powder for shot blast used for polishing a plasma display panel or the like. <P>SOLUTION: The powder for shot blast is prepared by mixing 1 to 30 mass% of ceramic powder with the metal powder having Hv 200 to 400 and used for machining the plasma display panel. In the powder for shot blast, the maximum grain diameter of the metal powder and ceramic powder is 0.2 to 0.9 times of the groove width to be machined. Furthermore, the powder for shot blast contains 5 to 20 mass% of the ceramic powder. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a metal powder for shot blasting used for polishing a plasma display panel or the like.

  Conventionally, shot blasting using metal powder has been used for processing rib grooves in plasma display panels. As the powder for shot blasting, metal powders having high processing capability, such as stainless steel (hereinafter referred to as SUS), heat-resistant steel (hereinafter referred to as SUH), etc. are generally used. However, there are cases where static electricity is charged on the substrate due to friction between the metal powder and the glass substrate during processing, and the dielectric is damaged by sparks or the like. That is, the rib material and the electrode may be damaged.

  As a means for removing the generated static electricity, for example, as disclosed in Japanese Patent Application Laid-Open No. 2001-345043 (Patent Document 1), a partition forming process of a plasma display panel using a high-pressure mixed fluid ejected from a nozzle of a sandblasting device Has proposed a static electricity removing method in which a plurality of address electrode terminal portions of a plasma display panel are grounded through a conductive magnetic powder adhered to a magnetic generator.

JP 2001-345043 A

  However, as disclosed in the above-mentioned Patent Document 1, many cases have been proposed in which a static electricity removing device such as a ground is connected to the base, but this method achieves a certain purpose, but it is not necessarily done. I can't say enough.

In order to solve the above-described problems, the inventors have intensively developed, and as a result, the metal powder is charged to the cathode by friction with glass, whereas CaCO ₃ , Al ₂ O ₃ , ZrO, SiO _Since ceramics such as ₂ are charged on the anode, it has been found that the charge amount is canceled and sufficiently reduced by mixing both powders at an appropriate blending ratio. The gist of the invention is that
(1) A metal powder for processing a plasma display panel, wherein 1-30 mass% of ceramic powder is mixed with metal powder of Hv 200-400.

(2) A powder for shot blasting, wherein the maximum particle size of the metal powder and ceramic powder according to (1) is 0.2 to 0.9 times the width of the groove to be processed.
(3) A powder for shot blasting comprising 5 to 20 mass% of the ceramic powder according to (1).

  As described above, according to the present invention, the charge amount is sufficiently lower than that of the prior art, and an excellent effect is obtained that enables extremely good processing.

Hereinafter, the present invention will be described in detail.
The metal powder according to the present invention is charged to the cathode by friction with the dielectric, whereas the ceramic powder is charged to the anode. Therefore, mixing the two powders at an appropriate ratio cancels the charge amount sufficiently. Has been found to be lower. However, when the mixing amount of the ceramic powder is less than 1%, the charge amount is not sufficiently reduced. Further, if it exceeds 30%, the amount of metal inevitably decreases, so that it cannot be productively processed. Therefore, the range is made 1-30%. Furthermore, it is preferably 5 to 20%.

  The composition of the metal powder is not particularly limited, but if the hardness is too low at Hv of less than 200, good processing cannot be performed. Further, if Hv exceeds 400, the dielectric may be damaged, which is not preferable. Therefore, a material having an Hv of 200 to 400 is optimal. As such a material, SUS type and SUH type are preferable in terms of both cost and quality. The maximum particle size of the metal powder powder and ceramic powder is preferably set to be 0.2 to 0.9 times the groove width to be processed. However, if it is less than 0.2, the impact energy at the time of a shot is small, and processing cannot be performed. On the other hand, if it exceeds 0.9, it will cause cracking. Therefore, the range is 0.2 to 0.9 times. Preferably it is 0.5 to 0.8 times.

The type of ceramic powder is not particularly limited, but considering cost, CaCO ₃ , Al ₂ O ₃ , ZrO, and SiO ₂ are optimal. Further, two or more kinds of these ceramic powders may be mixed and used.

Hereinafter, the present invention will be specifically described with reference to examples.
Each powder shown in Table 1 was prepared by gas atomization under conditions of a gas pressure of 5 MPa and a nozzle diameter of φ2 mm, and classified to −45 μm. The ceramic powder listed in Table 1 was mixed with a V-type mixer for 30 minutes. Each mixture at that time, metal powder hardness Hv, and a mixture with the maximum particle size were shot on a low-melting glass, and groove processing with a width of 50 μm was performed. Table 1 shows the results of the charge amount and cracking frequency in the case of the maximum particle size / working width at that time.

  The method for measuring the charge amount of the charged body is shown in FIG. 1 and FIG. FIG. 1 is a cross-sectional view of a static electricity measuring device, and FIG. 2 is a top view of the static electricity measuring device. As shown in this figure, rubber sheets 2 are attached to both surfaces of a steel plate 1, a base aluminum tape 3 is attached to one surface of the steel plate 1, and an alumina plate 5 is fixed to the base aluminum tape 3 thereon. To do. On this aluminum tape 3 for base, the electric wire 4 from which the coating on one side is peeled off is fixed with the aluminum tape 3 for base. The other side is taken out of the shot blasting machine and the amount of static electricity is measured. Reference numeral 6 denotes a glass plate, and 7 denotes a shot nozzle.

  As the shot conditions, the nozzle used at the time of processing is boron φ5, supply air: 0.23 MPa, pumping air: 0.20 MPa, internal pressure inside the nozzle at processing: 0.19 MPa, nozzle distance: 50 mm, abrasive supply amount : Groove machining with a width of 50 μm was performed at 69 rpm (MAX). As evaluation items at that time, the charge amount and the cracking frequency were measured. For the charge amount, use the static electricity measuring device shown in FIG. 1 and FIG. 2 described above, and for the cracking frequency, visually check the presence or absence of cracks as a dielectric shape after processing, and perform 10 blast treatments. On the other hand, the occurrence frequency of cracks and chips was measured. Moreover, about metal powder hardness, it carried out with 50 g of load loads with the Vickers hardness meter.

  As shown in Table 1, no. Nos. 1 to 12 are examples of the present invention. 13 to 20 are comparative examples. Comparative Example No. In No. 13, since the metal powder hardness was low, groove processing was impossible. Comparative Example No. No. 14 has a high cracking frequency due to its high metal powder hardness. Comparative Example No. No. 15 has a high charge amount and a high cracking frequency because the ceramic powder mixing amount is small. Comparative Example No. 16 is No.16. Since the ceramic powder mixing amount is small as in the case of 15, the charge amount is high and the cracking frequency is high. Comparative Example No. No. 17 could not be grooved because of the large amount of ceramic powder mixed.

  Comparative Example No. No. 18 As in the case of No. 17, the amount of ceramic powder mixed was so large that groove processing was impossible. Comparative Example No. In No. 19, since the ceramic powder mixed charge amount was high and the maximum particle size / working width was small, the charge amount was positive and groove processing was impossible. Comparative Example No. No. 20 had a high ceramic powder mixed charge amount and a large maximum particle size / working width, so the charge amount was positive and groove processing was impossible. On the other hand, No. which is an example of the present invention. It can be seen that Nos. 1 to 12 have a low charge amount and a low cracking frequency.

  As described above, by using the metal powder for shot blasting used for polishing of the plasma display panel or the like according to the present invention, the charge amount is sufficiently lower than that of the prior art, and the processing can be performed extremely well. This is an excellent effect.

It is sectional drawing of an electrostatic measurement apparatus. It is a top view of an electrostatic measurement device.

Explanation of symbols

1 Steel plate 2 Rubber sheet 3 Aluminum tape for base 4 Electric wire 5 Alumina plate 6 Glass plate 7 Shot nozzle


Patent Applicant Sanyo Special Steel Co., Ltd.
Attorney: Attorney Shiina

Claims (3)

In a metal powder for processing a plasma display panel, 1-30 mass% of ceramic powder is mixed with metal powder of Hv 200-400. A powder for shot blasting, wherein the maximum particle size of the metal powder and ceramic powder according to claim 1 is 0.2 to 0.9 times the groove width to be processed. A powder for shot blasting, wherein the ceramic powder according to claim 1 is mixed in an amount of 5 to 20 mass%.

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