KR20050065413A - Glass panel for cathode-ray tube - Google Patents

Abstract

By optimizing the surface state of the chamfer formed at the intersection of the inner and outer surfaces of the skirt section of the panel and the sealing end surface, it is possible to prevent the occurrence of the so-called triangular divergence during the sealing heat treatment of the panel and the perimeter, and Unnecessary sag is prevented, and damage caused by electric field concentration due to adhesion residue such as dirt is avoided.

The outer chamfered part 8 is formed in the intersection of the outer side 10 and the sealing end surface 6 of the skirt part 5 of the panel 1, and the unevenness | corrugation on the surface of this outer chamfered part 8 is carried out. When the average depth of Rz is set to Sm and the average period is Sm, the first rough surface 11 having 5 탆 ≤ Rz ≤ 30 탆 and 100 탆 ≤ Sm ≤ 400 탆 is formed. This 1st rough surface 11 is a predetermined area | region including the diagonal axis DA in the area | region over the whole periphery of the sealing end surface 6, or the outer chamfer 8, or in the outer chamfer 8 It is formed in the longitudinal center part of the edge part 4.

Description

Glass panel for cathode ray tube {GLASS PANEL FOR CATHODE-RAY TUBE}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a glass panel for a cathode ray tube, and more particularly, to an improvement technique of a chamfer formed at an intersection of an inner and an outer surface of a skirt portion of the panel and a sealing end surface, and a surface state around the chamfer.

As is well known, the cathode ray tube used for display apparatuses, such as a color television receiver, is a main glass component, the glass panel for cathode ray tubes (henceforth a panel) in which an image is reflected, and the glass funnel for cathode ray tube of the substantially funnel shape. (Hereinafter also referred to simply as perm). As shown in Fig. 4, the panel 1 comprises four substantially rectangular face portions 2 having an effective screen for displaying an image, and four connected to the face portions 2 through a blend R portion 3; The skirt portion 5 is formed from the edge portion 4, and the sealing end surface 6 sealed with the perimeter is formed at the open end of the skirt portion 5.

In the press forming process, the panel 1 is a molten glass mass (hereinafter referred to as a gob) in a receiving mold (female mold) composed of a low mold (bottom mold) and a side mold (shell mold). It is shape | molded by supplying it, and pressing this by a pressing (plunger metal mold). After the end of the press molding step, a polishing step of polishing a predetermined portion of the panel is performed as necessary.

In the press-molding step, it is preferable that the easy release (release) from the bottom mold or the shell mold of the panel at the time of removing the panel from the bottom mold is preferable, and it is preferable that wrinkles of glass do not occur. From this point of view, Patent Documents 1 to 4 described below include the curved portion extending from the outer surface of the panel 1 to the skirt portion 5 or the outer surface of the skirt portion 5 (outer surface and inner surface in Patent Document 4). It is disclosed that a rough surface made of predetermined minute unevenness is formed on the surface thereof, and the request thereof is made.

In addition, it is preferable that the sealing end surface 6 of the skirt part 5 of this panel 1 is easy to remove dirt, and it is preferable that it is formed so that the sealing strength with a perimeter may become high, and it is a penetrating image. (I) It is preferable that it is formed so that hardly the (wounds which penetrate a sealing end surface in the width direction) generate | occur | produce. In view of this, Patent Documents 5 and 6 below disclose that roughening surfaces formed of predetermined minute unevennesses are formed on the sealing end surface 6 of the panel 1 and comply with these requests.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2000-302464

[Patent Document 2] Japanese Patent Publication No. 38-4383

[Patent Document 3] Japanese Utility Model Publication No. 55-137450

[Patent Document 4] Japanese Utility Model Publication No. 54-26354

[Patent Document 5] Japanese Patent Application Laid-Open No. 2002-324497

[Patent Document 6] Japanese Patent Application Laid-Open No. 11-40081

Patent Documents 1 to 4 describe only the inner and outer side surfaces of the skirt portion 5 of the panel 1, and Patent Documents 5 and 6 describe only the sealing end surface 6 of the panel 1. It is. However, in this kind of panel 1, a chamfer may be formed in the intersection of the outer side surface of the skirt part 5 and the sealing end surface 6 in some cases. Nevertheless, not only the patent documents 1 to 6 but also other patent documents and non-patent documents describe nothing about the surface state of the chamfer.

In the present situation, for example, the sand blasting method is widely adopted as a method of forming irregularities on the molding surface of the mold, and after forming the panel 1, the chamfer portion is formed by polishing and the finishing processing thereof is performed. It is customary that a chamfered part is mirror surface or substantially mirror surface, for example, as a cause. In addition, the ease of removal of dirt is considered as a factor, and the chamfer is generally mirror surface or substantially mirror surface.

However, if such a chamfer is mirror surface or substantially mirror surface, the scratches (penetration) such as abrasion are particularly likely to occur in the diagonal portion thereof, and in particular during the temperature raising process at the time of sealing the panel 1 and the perimeter, the outer chamfer portion Thermal stress concentrations occur in the diagonals. As a result, cracks originating from the scratches are generated, and the cracks advance in the temperature raising process, so that damage occurs in a triangular pyramid shape from the periphery of the diagonal portion of the chamfer to the edges 4 and so-called triangular divergence. A fatal defect called "development" occurs. This problem is remarkable as the face outer surface of the panel 1 is flattened.

In addition, if the chamfered part is mirror surface or substantially mirror surface as mentioned above, the problem as shown below will be caused. That is, as shown in Fig. 5, at the time of sealing the panel 1 and the perimeter 20, the frit glass 30 is interposed on the sealing end face 26 of the perimeter 20 at the initial stage. In the state, the panel 1 in which the sealing end face 6 faces downwards is placed, and the frit glass 30 is crimped | bonded by the sealing end face 6 of this panel 1. Thereby, the frit glass 30 protrudes to both inside and outside, and ascends upward along the chamfers 7 and 8 inside and outside of the panel 1, one end of which is indicated by the dashed line in the same diagram. The chamfer 7.8 of (1) and the chamfer 27,28 of the perforator 20 are substantially equally covered, or the state comes close to this. However, if the chamfers 7 and 8 of the panel 1 are mirrored or approximately mirror surfaces, the frit glass 30 once raised along the chamfers 7 and 8 causes the chamfers 7 and 8 to be removed over time. Therefore, it flows easily, and until this frit glass 30 becomes low temperature and it solidifies, as shown by the solid line in the same figure, the frit glass 30 becomes unnecessarily collapsed. When the chamfers 7 and 8 of the panel 1 are exposed or close to the chamfers 7, the glass valves obtained by sealing the panel 1 and the perforator 20 tend to be cracked and withstand use. This results in a problem that, for example, the waste can only be disposed of as a defective product in the inspection process.

In order to avoid such a problem, the chamfers 7 and 8 may be roughened. However, simply by roughing the dirts attached to the chamfers 7 and 8 in the manufacturing process of the panel, it is difficult to fall off. As a result, the glass valve is more likely to be manufactured with dirt remaining. In addition, when such a glass valve is used for a cathode ray tube, there is a possibility that electric field concentration occurs in residual portions such as dirt, causing new problems such as breakage of the cathode ray tube.

This invention is made | formed in view of the said situation, and the so-called triangular divergence generate | occur | produces at the time of sealing heat processing of a panel and a perm by optimizing the surface state of the chamfer part formed in the intersection part of the inner and outer side of a skirt part of a panel, and the sealing end surface. It is a technical problem to prevent this from happening, to prevent the drooping of the frit glass, and to avoid the abnormality of the electrical operation due to the adhesion remaining such as dirt.

SUMMARY OF THE INVENTION The present invention has been made to solve the above technical problem, and includes a substantially rectangular face portion and a skirt portion connected at approximately a right angle through a blend R portion at a circumferential edge of the face portion, wherein each of the skirt portions borders a diagonal axis. In a glass panel for cathode ray tubes having a side portion and having a sealing end face at an opening end thereof, an outer chamfer portion is formed at an intersection of the outer side face of the skirt portion and the sealing end face, and the surface of the outer chamfer portion has a When the average depth of the unevenness is set to Rz and the average period is set to Sm, it has a first roughness of 5 µm ≤ Rz ≤ 30 µm and 100 µm ≤ Sm ≤ 400 µm. The outer chamfer is preferably an inclined surface (C surface) or an approximately inclined surface formed in an area of 1/50 to 1/5 of the surface width of the sealing cross section, but may be an arc surface (R surface) or an approximately arc surface formed in the same area. good. In addition, the measurement of said Rz and Sm is based on JIS BO601: 1982.

According to this configuration, the surface of the outer chamfer formed at the intersection of the outer surface of the skirt portion and the sealing end surface of the panel has a first rough surface which is not a mirror surface or a substantially mirror surface, and the first rough surface is within the above numerical range. As a result, through images (scratches penetrating the chamfers in the width direction) are less likely to occur in the outer chamfer, and the occurrence probability of the so-called triangular splitting during sealing heat treatment with the funnel is reduced, and unnecessary deflection of the frit glass is prevented. This is suppressed, and dirt and the like remain adhered to, thereby preventing abnormality in electrical operation.

That is, if Rz <5 占 퐉, the depth of the unevenness is too small, and when the panel and the perimeter are sealed through the frit glass, the frit glass once raised along the outer chamfer can be sufficiently suppressed. After the solidification, the frit glass is unnecessarily struck, and it becomes difficult to obtain a good sealing shape. On the other hand, if Rz> 30 micrometer, since the depth of unevenness | corrugation is too big | large, a deviation arises in the temperature distribution between a recessed part and a convex part at the time of temperature rising in the sealing process of a panel and a perimeter, and an outer chamfered part Since the softening flow rates of the frit glass in contact with each other are greatly different in the concave and convex portions, it becomes difficult to penetrate and react the frit glass under uniform conditions on the outer chamfered portion, even in this case. Is difficult to obtain. Therefore, in avoiding these problems, it is advantageous for Rz to be in the above numerical range.

In addition, when Sm <100 micrometers, for example, since a recessed part is too narrow, frit glass becomes a viscous slurry state, and it becomes difficult to fill frit glass in a recessed part, and therefore air remains in a recessed part, In addition, the adhesion strength between the outer chamfered portion and the frit glass and the weld strength are lowered. In addition, if the recess is too narrow in this way, since the dirt and the like attached to the outer chamfered portion are hard to fall off during the manufacturing process of the panel, it causes a situation that the glass valve is manufactured with the dirt remaining in the recess. . And when such a glass valve is used for a cathode ray tube, electric charge concentration may generate | occur | produce in the residual part, such as dirt, and the like, and there exists a possibility of attracting the abnormality of electrical operation (for example, insulation breakdown). On the other hand, if Sm> 400 µm, for example, the concave portion is too wide, it becomes a smooth surface as a whole, and it is impossible to reliably suppress the formation of a penetrating image, and at the time of sealing the panel and the perimeter, the outer chamfered portion is once Therefore, it becomes impossible to fully suppress the flow of the raised frit glass, and it is difficult to obtain a good sealing shape. In addition, if the surface is smooth as a whole, the contact area between the outer chamfered portion and the frit glass becomes small, and there is a fear of causing a decrease in the sealing strength. Therefore, in avoiding these problems, it is advantageous for Sm to be in the above numerical range.

When the first roughness of the outer chamfered portion is 5 µm ≤ Rz ≤ 30 µm and 100 µm ≤ Sm ≤ 400 µm, the above-mentioned advantages can be accurately enjoyed, and only Rz is within the above numerical range. Or if only Sm is within the above numerical range, it is impossible to enjoy such an advantage. In other words, if the values of Rz and Sm do not exist within the appropriate numerical range, there may not be any surface characteristics excellent in contact conditions and dirt removal of the frit glass. In view of the above, it is more preferable from the viewpoint of performance safety that the first roughness of the outer chamfered portion is 10 μm ≦ Rz ≦ 20 μm and 160 μm ≦ Sm ≦ 350 μm.

In this case, if the main purpose is to prevent the occurrence of so-called triangular divergence and the like, it is preferable to form the first rough surface in a predetermined region including the diagonal axis in the outer chamfered portion. Specifically, it is preferable that the region where the first rough surface is formed is an area of 5 mm or more and 100 mm or less from the diagonal axis toward the longitudinal center portion side of each edge portion.

This makes it difficult to generate a penetrating image around the diagonal portion of the outer chamfer, so that the probability of occurrence of cracks originating from such scratches and so-called triangular divergence due to the expansion of the cracks decreases.

On the other hand, if the main purpose is to improve the welding strength with the frit glass, etc., it is preferable to form the first rough surface in the longitudinal center portion of the edge portion of the outer chamfered portion. Specifically, the region where the first rough surface is formed is preferably 5 mm or more from the diagonal axis toward the longitudinal center portion side of the edge portion, and is an area in the longitudinal center portion of the edge portion except for an area of 100 mm or less. Moreover, it is preferable that especially a 1st rough surface is formed in a long side part, or it is preferable that a longer side part is formed in a long area | region in a longitudinal direction rather than a short side part.

In this way, the frit glass is satisfactorily filled in the concave portion at the surface of the central portion of the edge length of the outer chamfer and the contact area between the uneven surface and the frit glass becomes large, so that the frit glass at the central portion in the longitudinal direction of the edge portion The welding strength is sufficiently high, and the sealing strength with the perimeter is efficiently improved.

In the above structure, the average depth Rz and the average period Sm of the unevenness are at least in the continuous portion of the skirt outer side surface continuous to the surface of the outer chamfer portion as the first rough surface. It is preferable to form a second rough surface within the same numerical range as.

In this case, since the frit glass which once climbed up to the continuous part of the outer side continuous to the outer chamfered part of the skirt part at the time of sealing of the panel and the perimeter is prevented from flowing down even in the continuous part, unnecessary fritting of the frit glass is caused. And cracking of the glass valve resulting from this becomes less likely to occur. The continuous portion from the outer chamfer on the outer side of the skirt may be a narrow area up to about 3 to 10 mm away from the outer chamfer, but, for example, if it is a large area to the brake line or the mold match line, Good release property is obtained.

In addition, it is preferable that the average depth Rz and the average period Sm of the unevenness are also rough surfaces in the same numerical range as that of the first rough surface in the sealing end surface continuous to the surface of the outer chamfered portion made of the first rough surface. .

This makes it easy to remove dirts on the sealing end face, and it is difficult to form a penetrating image, and it is possible to obtain a desired sealing strength by frit glass.

In addition, the present invention, which is made to solve the above technical problem, has a generally rectangular face portion and a skirt portion connected at approximately a right angle through a blend R portion at a circumferential edge of the face portion, wherein the skirt portion borders a diagonal axis. In the glass panel for cathode ray tubes having each edge portion and having a sealing end surface at the opening end thereof, an inner chamfer portion is formed at the intersection of the inner side of the skirt portion and the sealing end surface, and the inner chamfering portion is provided. The surface has a third roughening surface of 5 µm ≤ Rz ≤ 30 µm and 100 µm ≤ Sm ≤ 400 µm when the average depth of irregularities is Rz and the average period is Sm. In addition, the inner chamfer of this form may be formed in place of the outer chamfer described above, or may be formed together with the outer chamfer. The inner chamfer portion is preferably an inclined surface (C surface) formed in an area of 1/50 to 1/5 of the surface width of the sealing cross section or an approximately mirror surface, but an arc surface (R surface) or approximately circular formed in the same area. It may be a surface.

According to such a structure, since the surface of an inner chamfer part has a 3rd rough surface, the effect similar to the case where the surface of an outer chamfer part has a 1st rough surface as described above is acquired.

In this case, the said 3rd rough surface may be formed in the predetermined area | region including the diagonal axis in an inner chamfer part, and may be provided in the longitudinal center part of the edge part in an inner chamfer part separately from this.

In this way, as described above, the first rough surface is substantially formed in a predetermined region including a diagonal axis in the outer chamfer, or in the longitudinal center portion of the side of the outer chamfer. The same effect is obtained.

In the above structure, the average depth Rz and the average period Sm of the unevenness are the same as those of the third roughness on at least the continuous portion of the inner side of the skirt portion continuous to the surface of the inner chamfered portion of the third roughness. It is preferable to form the fourth roughening surface within the numerical range.

In this way, as described above, an effect substantially the same as in the case where the second rough surface is formed on at least the continuous portion of the outer side of the skirt portion continuous to the surface of the outer chamfered portion formed of the first rough surface is obtained.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to an accompanying drawing. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing a glass panel for a cathode ray tube according to an embodiment of the present invention. Fig. 2 is an enlarged perspective view showing a main part of the panel, and is a longitudinal sectional front view of the main part of a glass valve sealing the panel and a permeate through frit glass. . In addition, since the basic component shown in FIG. 4 is the same as the conventional panel shown in FIG. 4, the panel shown in FIG. 1 attaches | subjects the same code | symbol to the common component in both, and abbreviate | omits the detailed description.

As shown in FIG. 1, the panel 1 which concerns on embodiment of this invention is the outer chamfer (bevel surface) 8 in the intersection of the outer surface 10 of the skirt part 5, and the sealing end surface 6. As shown in FIG. In this embodiment, the outer chamfer 8 is formed over the whole circumference of the sealing end surface 6. The outer surface of the chamfered portion 8 has a first roughness in which the average depth Rz of the irregularities is 5 µm ≤ Rz ≤ 30 µm, and the average period Sm of the irregularities is 100 µm ≤ Sm ≤ 400 µm. (11). Moreover, it is more preferable that the said average depth Rz of this 1st rough surface 11 is 10 micrometer <= Rz <= 20micrometer, and the said average period Sm is 160 <= Sm <= 350micrometer.

As shown in Fig. 2, the outer chamfered portion 8 is an inclined surface extending from one side edge 6a of the sealing end face 6 to one side edge 10a of the outer surface 10 of the skirt portion 5 in this embodiment. It is formed as (C surface) and is formed in the area | region of 1/50-1/5 of the surface width S of the sealing end surface 6. As shown in FIG.

In addition, on the outer side surface 10 of the skirt portion 5 continuous to the outer chamfer 8, the average depth Rz and the average period Sm of the unevenness on the surface of the continuous portion are at least described above. The second rough surface 12 which is in the same numerical range as the first rough surface 11 of is formed. The second rough surface 12 may be formed to a position about 3 to 10 mm away from the outer chamfer 8 (one edge 10a) on the outer surface 10 of the skirt portion 5, but the brake It is preferable that it is formed to the line B, or to the mold match line M, or to the intermediate position between each of the lines B and M.

Moreover, the 1st rough surface 11 is 5 mm from the predetermined area | region including the diagonal axis DA of the outer chamfering part 8, for example, from the diagonal axis DA toward the longitudinal center part side of each edge part 4. As shown in FIG. The above is formed in the area | region below 100 mm, Preferably the 2nd rough surface 12 is also formed in this area | region. Moreover, the 1st rough surface 11 is 5 mm or more toward the longitudinal center part of each edge part 4 from the longitudinal center part of the edge part 4 in the outer chamfer 8, for example, diagonal axis DA. And may be formed in the longitudinal central portion region of the edge portion 4 except the region of 100 mm or less. In this case, however, the first rough surface 11 is formed only on the long side portion 4 of each side portion 4, or the first rough surface 11 is formed so that the long side portion 4 is longer than the short side portion 4. It is preferable to form. The surface of the sealing end face 6 may also be a rough surface in which the average depth Rz and the average period Sm of the unevenness are within the same numerical range as those of the first rough surface 11.

On the other hand, the panel 1 has an inner chamfer (lip) 7 also formed at the intersection of the inner surface 9 of the skirt portion 5 and the sealing end surface 6, and the inner chamfer 7 ) Is also formed over the entire circumference of the sealing end face 6. The surface of the inner chamfer 7 is a third rough surface 13 in which the average depth Rz and the average period Sm of the unevenness are within the same numerical range as the first rough surface 11. In addition, on the inner surface 9 of the skirt portion 5 continuous to the inner chamfer 7, the average depth Rz of the unevenness on the surface of the continuous portion and the average period Sm thereof are at least. A fourth rough surface 14 is formed within the same numerical range as the first rough surface 11.

According to the panel 1 having the above configuration, as shown in FIG. 3, the outer chamfer 8 and the inner chamfer 7 on both sides of the sealing end face 6 of the panel 1 are provided. Since the surfaces are respectively the first rough surface 11 and the third rough surface 13, both the chamfered portions (1) at the time of sealing the panel 1 and the perforation 20 via the frit glass 30 are interposed. The frit glass 30 which climbed along 7,8 can fully be suppressed, and it does not become the state which the frit glass 30 unnecessarily struck after solidification, and the favorable sealing shape is obtained. This advantage is that the surfaces of the outer surface 10 and the inner surface 9 of the skirt portion 5 that are continuous to both chamfers 7, 8 are respectively the second rough surface 12 and the fourth rough surface 14. It becomes possible to obtain remarkably further by becoming.

Moreover, in particular, since the surface of the outer chamfered portion 8 is the first rough surface 11, it is difficult to generate a penetrating image (wounds that penetrate the chamfered portion in the width direction) on the outer chamfered portion 8, thereby. It is possible to reduce the occurrence probability of the so-called triangular splitting at the time of heat treatment in the sealing step with the funnel 20 or the like. This advantage is obtained under the condition that the first rough surface 11 is formed in a predetermined region including the diagonal axis DA of the outer chamfered portion 8.

In addition, since the first rough surface 11 and the second rough surface 12 formed in the both chamfers 7 and 8 are in the numerical range described, the both chamfers 7 in the manufacturing process of the panel 1 are carried out. Since dirt attached to 8 can be easily dropped, the situation that the glass valve 40 is manufactured in the state where dirt etc. remain in the recessed part of both roughening surfaces 11 and 12 is avoided. As a result, when the glass valve 40 is used for the cathode ray tube, the attraction such as breakage of the cathode ray tube due to generation of electric field due to dirt or the like is prevented.

(Example)

As shown in Table 1 below, as a first embodiment of the present invention, the first rough surface 11 and the third rough surface 13 in the outer chamfer 8 and the inner chamfer 7 of the panel 1 ), The surface depth Rz of the unevenness was set to 5 µm, and the surface period Sm was set to 100 µm, and Rz was set to 10 µm in the same manner as in Example 2. To produce a panel 1 having a thickness of 160 μm, and as Example 3, a panel 1 having a Rz of 15 μm and a Sm of 250 μm was similarly produced. In addition, the panel 1 which made Sm 350 micrometers was produced, and as Example 5, the panel 1 which made Rz 30 micrometers and Sm 400 micrometers was similarly produced.

On the other hand, as shown in Table 2 below, as Comparative Example 1, as in the case described above, Rz was set to 3 µm and Sm was set to 90 µm, and as Comparative Example 2, Rz was similarly prepared. A panel 1 having a thickness of 3 μm and an Sm of 160 μm was produced. As Comparative Example 3, a panel 1 of Rz of 15 μm and Sm of 90 μm was similarly produced. Similarly, the panel 1 in which Rz was 40 micrometers and Sm was 250 micrometers was produced, and as Comparative Example 5, the panel 1 which similarly Rz was 40 micrometers and Sm was 450 micrometers was produced.

In Examples 1 to 5 and Comparative Examples 1 to 5, both of the outer chamfered portion 8 and the inner chamfered portion 7 were formed by 1/8 of the surface width S of the sealing end face 6. The area was formed over its entire circumference. In addition, these panels 1 have an aspect ratio of 4: 3, an outer diameter in the diagonal axis X direction of 724.8 mm, a radius of curvature of the outer surface of the face portion 2 on the diagonal axis X of 100000 mm, and an overall panel height (face). The dimension in the parallel axis direction from the outer outer surface to the sealing end face) was 100.0 mm, and the surface width S of the sealing end face 6 was 11.4 mm.

Next, while manufacturing the perimeter 20 corresponding to these panels 1, these perimeters 20 are installed in a predetermined jig, and on the sealing end surface 26 of the perimeter 20, frit glass (30) (Asahi Glass Co., Ltd. product; ASF-1307B) The slurry formed by disperse | distributing to the organic plating agent is apply | coated, dried, and the panel of Examples 1-5 and Comparative Examples 1-5 on the sealing cross section. (1) was mounted, respectively. Thereafter, they are passed through a heat treatment furnace having a predetermined temperature gradient maintained at a maximum temperature of 450 ° C. for 20 minutes, and the frit glass 30 is sealed with the end faces 6 and 26 of the panel 1 and the perm 20. By reacting, the glass valve 40 formed by sealing each panel 1 and each permeer 20 was obtained.

 In this case, each of the glass valves 40 mounted on each of the perforations 20 through the frit glass 30 of the panels 1 of Examples 1 to 5 and Comparative Examples 1 to 5 was subjected to a heat treatment furnace. The process of sealing the frit glass by passing it was performed, and the size of the degree of triangular splitting or breakage that was caused by the observation was visually observed. The results are shown in the fourth row of each of Tables 1 and 2 below as three stages of evaluation. In this three-step evaluation, the ○ mark indicates that not only triangular divergence but also small defects have never occurred, and the △ symbol does not cause triangular splitting, but a small flaw occurs even once, and the X mark indicates a triangular splitting or this. It means that a nice break occurred once.

In addition, the sealing shape after heat processing with respect to each glass valve which sealed the panel 1 of Examples 1-5 and Comparative Examples 1-5 with the frit glass 30 via the frit glass 30 was carried out. Good or bad of the surrounding shape) was observed visually. The results are shown in the fifth row of each of Tables 1 and 2 below as three-stage evaluations. In this three-stage evaluation, the o mark indicates that the sealing shape is close to the ideal shape, and the o mark indicates that the sealing shape is slightly different from the abnormal shape, but there is no fear of cracking, etc., and the x mark indicates that the sealing shape is different from the abnormal shape. Significantly different means that there is a risk of cracking.

Moreover, when each glass valve which has the panel 1 of Examples 1-5 and Comparative Examples 1-5 obtained as mentioned above is used as a cathode ray tube, whether electrical insulation is stably obtained, ie, the panel 1 It was examined whether dirt around the sealed end surface 6 of the was removed. The results are shown in the sixth row of each of Table 1 and Table 2 below as a three-step evaluation. In this three-step evaluation, the symbol ○ indicates that no electric field concentration occurred in the dirt section and no insulation breakdown occurred. The symbol △ indicates that no crack occurred due to the electric field concentration in the dirt section. Occurrence and x mark means that the crack caused by the electric field concentration in the dirt part occurred at least once to the extent that insulation breakdown occurred.

TABLE 1

Example 1 Example 2 Example 3 Example 4 Example 5 Rz (μm) 5 10 15 20 30 Sm (㎛) 100 160 250 350 400 Triangular divergence ○ ○ ○ ○ ○ Seal shape △ ○ ○ ○ △ Electrical insulation ○ ○ ○ ○ ○

TABLE 2

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Rz (μm) 3 3 15 40 40 Sm (㎛) 90 160 90 250 450 Triangular divergence × × ○ ○ △ Seal shape △ × ○ ○ △ Electrical insulation △ ○ × × ×

According to the above Table 1, the first rough surface 11 and the third rough surface 13 which form the surface of the panel 1 of the Examples 1-5, ie, the outer chamfer 8 and the inner chamfer 7, are The glass valve 40 manufactured by using the panel 1 in the numerical range of 5 µm ≤ Rz ≤ 30 µm and 100 µm ≤ Sm ≤ 400 µm is excellent in triangular divergence and electrical insulation and has a sealed shape. Although there existed a thing which fell slightly, about the grade which does not produce a trouble such as a crack, it confirmed that all were the high quality glass valve 40.

In addition, the first rough surface 11 and the third rough surface 13 which form the surface of the panel 1 of the Examples 2 to 4, that is, the outer chamfer 8 and the inner chamfer 7 are 10 μm ≦ Rz ≦. Since the glass valve 40 manufactured using the panel 1 which is 20 µm and which is within the numerical range of 160 µm ≤ Sm ≤ 350 µm, all three elements of triangular divergence, electrical insulation, and sealing shape are excellent. Confirmed that the glass valve 40 is extremely high quality.

On the other hand, according to the above Table 2, the first rough surface 11 and the third rough surface 13 which form the surface of the panel 1 of the comparative examples 1-5, ie, the outer chamfer 8 and the inner chamfer 7, The glass valve 40 manufactured by using the panel 1 having a diameter of 5 µm ≤ Rz ≤ 30 µm and deviating from the numerical range of 100 µm ≤ Sm ≤ 400 µm is triangulated and sealed for all the comparative examples. Since any one of the shape and the electrical insulation is deteriorated to an unusable degree, it was confirmed that all of them are the glass valves 40 to be disposed of.

As mentioned above, according to the glass panel for cathode ray tubes which concerns on this invention, the surface of the outer chamfer formed in the intersection part of the outer side of a skirt part, and the sealing end surface is 5 micrometer << average depth (Rz) <30 micrometers, and also 100 micrometers. Since the first rough surface has an average period Sm of 400 µm, a penetrating image is less likely to occur in the outer chamfering portion, and the probability of occurrence of so-called triangular divergence at the time of sealing with the perforator (such as during heat treatment) can be reduced. In addition, it is possible to suppress unnecessary sagging of the frit glass and to obtain a good sealing form. Further, it is possible to infiltrate and react the frit glass on the surface of the outer chamfering part under uniform conditions, to increase the welding strength with the frit glass, and to obtain a good sealing state by this. In addition, since the dirt etc. which adhered to the outer chamfered part can be easily removed in the manufacturing process of the panel, when using the glass valve manufactured in the state which the dirt etc. remain in the recessed part for a cathode ray tube, It is possible to avoid dielectric breakdown and the like. In addition, even when the surface of the inner chamfered portion formed at the intersection of the inner surface of the skirt portion and the sealing end surface has a rough surface within the same numerical range as the above first rough surface, the above advantages can be obtained.

1 is a perspective view showing a glass panel for a cathode ray tube according to an embodiment of the present invention.

2 is a perspective view showing a main part of a glass panel for a cathode ray tube according to an embodiment of the present invention.

Fig. 3 is an enlarged vertical sectional front view of a main portion showing a glass valve for cathode ray tube manufactured using a glass panel for cathode ray tube according to an embodiment of the present invention.

4 is a perspective view showing a glass panel for a conventional cathode ray tube.

5 is an enlarged longitudinal sectional front view of a main portion showing a problem of a glass valve for cathode ray tube manufactured using a glass panel for conventional cathode ray tube.

[Brief Description of Drawings]

1: Panel (glass panel for cathode ray tube) 2: Face part

3: Blend R part 4: Edge part

5: Skirt part 6: Sealing cross section (sealing cross section of panel)

7: Inner Chamfer 8: Outer Chamfer

9: inner side (inner side of skirt) 10: outer side (outer side of skirt)

11: Article One 12: Article Two

13: Article 3 surface DA: diagonal axis

Claims (8)

A substantially rectangular face portion and a skirt portion connected at about a right angle to the peripheral edge of the face portion through a blend R portion, the skirt portion having respective edge portions bordering the diagonal axis, and a sealing end face at the opening end thereof. In the glass panel for a cathode ray tube which has a structure which has The outer chamfered portion is formed at the intersection of the outer side of the skirt portion and the sealing end face, and the surface of the outer chamfered portion has a mean depth of irregularities of Rz and an average period of Sm, which is 5 μm ≦ Rz ≦ 30 μm. And a first rough surface having a thickness of 100 µm ≤ Sm ≤ 400 µm. The glass panel for a cathode ray tube according to claim 1, wherein a first rough surface is formed in a predetermined region including a diagonal axis in the outer chamfer. The glass panel for cathode ray tube according to claim 1, wherein a first rough surface is formed in a longitudinal center portion of the edge portion of the outer chamfer portion. The average depth Rz and the average period of unevenness in any one of Claims 1-3 in the continuous part of the skirt outer side surface continuous to the surface of the outer chamfer which became the said 1st rough surface. A glass panel for cathode ray tubes, characterized in that Sm) has formed a second rough surface within the same numerical range as that of the first rough surface. A substantially rectangular face portion, and a skirt portion connected at about a right angle to the peripheral edge of the face portion through a blend R portion, the skirt portion having each edge portion bordering the diagonal axis, and having a sealed end surface at the opening end thereof. In the glass panel for a cathode ray tube composed of, The inner chamfered portion is formed at the intersection of the inner side of the skirt portion and the sealing end face, and the surface of the inner chamfered portion has a mean depth of irregularities of Rz and an average period of Sm. And a third roughened surface having a thickness of 100 µm ≤ Sm ≤ 400 µm. The glass panel for a cathode ray tube according to claim 5, wherein a third roughening surface is formed in a predetermined region including a diagonal axis in the inner chamfer portion. The glass panel for a cathode ray tube according to claim 5, wherein a third roughened surface is formed in a longitudinal center portion of the edge portion of the inner chamfered portion. 8. The average depth Rz and the average period of unevenness in any one of Claims 5-7 in at least the continuous part of the inner surface of the skirt part continuous with the surface of the inner chamfer part which became the said 3rd rough surface. A glass panel for a cathode ray tube, wherein Sm) forms a fourth roughness surface within the same numerical range as the third roughness surface.