JPS60251253A - Color picture tube - Google Patents

Abstract

PURPOSE:To obtain a color picture tube realizable easily a high definition television image by forming a member such as shadow mask, frame, inner shield with a material contg. Fe and Ni as the main components and suitable quantities of P, S, As, Sb, etc. CONSTITUTION:At least one member of shadow mask, frame and inner shield is formed with the material contg. Fe and Ni as the main components, 0.002- 0.1wt% preferably, 0.005-0.03% of either element in P, S, As, Sb. Since said material has low endurance and tensile strength properties and superior in formability, highly precise forming becomes possible by applying said material to said member of color picture tube, and the high definition television image is realized easily. Said adding elements such as P, S, As, Sb deposit at crystal grain boundary by annealing to the higher concn. than average grain boundary concn., grain boundary is made brittle easily and the preferable efficiency is exhibited.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to improvements in color picture tubes.

[Technical background of the invention and its problems]

Generally, a color picture tube has a configuration shown in FIG. That is, 1 in the figure is a glass envelope. This envelope 1
The neck portion 2 at one end is provided with, for example, an in-line electron gun 3, and the face portion 4 at the other end facing the electron gun 3 is provided with a large number of fluorescent lights divided into red, blue, and green. A surface 5 is provided. A shadow mask 6 having a large number of beam apertures is disposed adjacent to the fluorescent surface 5 of the light source. This shadow mask 6 is attached to a frame 7 via a locking tool 8, and the frame 7 has an inner shield 9 on the electron gun 3 side for blocking earth's magnetic field.
is installed. In a color picture tube with such a configuration, the electron beam 11 emitted from the electron gun 3 is focused,
It is accelerated, deflected by a deflection device 10, and impinges on the fluorescent surface 5 through the aperture of the shadow mask 6, thereby reproducing a color image.

By the way, the members of the shadow mask, frame and inner shield used in the color picture tube are conventional).
It was made of iron material Fe, which has good etching properties and formability, and is easy to form an oxide film that contributes to reducing electron beam reflection. However, recently, with the practical use of computer displays, teletext broadcasting, satellite broadcasting, captain systems, etc., the ``easiness of viewing'' of TV screens has improved.
As more emphasis has been placed on "fineness," it has become difficult to use members such as shadow masks made of rimmed steel or At-killed steel for the following reasons.

That is, in general, when a color picture tube is operated, the temperature of each member increases to 30 to 100 DEG C., and for example, in the case of a shadow mask, the molded shape is distorted due to thermal expansion, ie, so-called doming occurs. As a result, the relative positional relationship between the aperture of the shadow mask, which should be located on the trajectory of the electron beam, and the phosphor layer on the phosphor surface is shifted, and a color shift phenomenon called purity drift (PD) occurs. In the detailed and easy-to-see color picture tube described above, the pitch and diameter of the apertures in the shadow mask are very small, so the degree of color shift is dependent on the amount of relative positional shift between the apertures in the shadow mask and the phosphor layer on the phosphor surface due to doming. is significantly larger than that for consumer use, and conventional shadow masks made of iron (Fe) are not practical.

For this reason, Fe-Ni, which has a small coefficient of thermal expansion,
It has been proposed to form components for color picture tubes, such as shadow masks, made of alloys such as amber (36Ni-Fe). However, the formability of amber is poorer than that of conventional iron materials, and dents usually occur from the spherical surface of the shadow mask toward the electron gun. This is called springback of the shadow mask, and when an amber mask is used, the dents especially around the mask are large and the relative position from the face surface shifts, making it difficult to use as a color picture tube.

[Purpose of the invention]

An object of the present invention is to provide a color picture tube that can easily realize high-quality television images.

[Summary of the invention]

In the present invention, at least one member of the shadow mask, the frame, and the inner shield is mainly composed of Fe and N1, and contains any one of the elements phosphorus, sulfur, arsenic, and antimony in an amount of 0.002 to O', 1 iff i The main idea is to form the material preferably from a material containing 0.005 to 0.03% by weight.

Such materials have low proof stress and tensile strength and are excellent in moldability, so if they are applied to color picture tubes, highly accurate molding becomes possible.

In particular, when used to form a shadow mask, a shadow mask with a normal spherical surface with little springback can be realized.

5- The above-mentioned elements of phosphorus, sulfur, arsenic, and antimony tend to segregate at grain boundaries during annealing, and because they tend to cause grain boundary embrittlement, they have the effect of reducing yield strength and tensile strength. The reason for limiting the content ratio of these elements to the above range is that if the content ratio of the element is less than 0.002% by weight, the grain boundary embrittlement phenomenon will be noticeable no matter what conditions the material to which this element is added is heat-treated. This makes it difficult to significantly reduce the tensile strength. On the other hand, if the content of the element exceeds 0.1% by weight, cracks are likely to occur during forging, and even if no cracks occur during forging, cracks may occur during molding of shadow masks, etc. .As a result of the increase in 2-chip force, the springback phenomenon becomes even more pronounced.

Therefore, it is unsuitable for members such as shadow masks.

FIG. 2 shows the relationship between the amounts of phosphorus, sulfur, arsenic, and antimony added and 0.2% proof stress, taking phosphorus as an example. When the annealing temperature of the material is 800℃ (curve A) and when the annealing temperature is 1100℃, 6-1 (curve B) is shown, but although there is a change in the value of 02-chi yield strength, 0 and 2 depending on the amount of phosphorus added The tendency of multi-proof strength values is the same. In particular, when the amount of phosphorus added is 0.1% by weight or more, the coefficient of thermal expansion is 25-50 when measured after annealing the material at 950°C. 2 compared to the material's 15X10'
This causes an increase in color shift as a shadow mask that is ~3 times larger. When using sulfur as the element, it is desirable to set the upper limit to 0.05% O. As a heat treatment method for a material containing an element such as phosphorus as described above, (a) the material is heated to the austenite region. (b) After heating to the austenite region, aging treatment is performed at a lower temperature than that temperature and the temperature is returned to room temperature. Through such heat treatment, the average elements (p, S, As, Sb
) A material with a higher concentration than the average elemental purity within the grain can be obtained. In addition, in the above method, the temperature increase rate is 1. Differences occur in the crystal grain size of various materials and the concentration of elements concentrated at grain boundaries depending on the holding temperature, time, and velocity, so it is necessary to select conditions corresponding to the content of the elements.

However, the yield strength and tensile strength of the material tend to be lowered more effectively when strong processing is not added in the middle.

[Embodiments of the invention]

Examples of the present invention will be described in detail below.

Example 1 First, the main component was 36-coefficient Ni-Fe, and P was 0.00.
An ingot of an alloy (Invar) containing 5% by weight and incidental components was prepared, and annealing, hot working, and cold working were repeated to produce a plate material with a thickness of 0.15 runs. Subsequently, this plate material was coated with a photosensitizer, exposed to four images, and etched by burning to produce a flat mask material having a large number of holes. Subsequently, the flat mask material was subjected to Makabe annealing at 950°C, cooled in a furnace, held at 700°C for 1 hour, and then sealed in an inert gas and cooled to room temperature. Next, the material was pressed, degreased, pickled, washed with water, and then blackened in air at 600° C. for 30 minutes to produce a shadow mask.

Example 2 A shadow mask was manufactured in the same manner as in Example 1 except that an alloy consisting of 36% Nl-Fe containing 0.05% by weight of P was used.

Example 3 A shadow mask was manufactured in the same manner as in Example 1, except that an alloy consisting of 36% Ni-Fe containing 0.07% by weight of P was used.

Comparative Example I A shadow mask was manufactured by the force method in the same manner as in Example 1, except that a 36% Nl-Fe carbon alloy containing 0.0005% by weight of P was used.

Therefore, the conditions of the shadow masks of Examples 1 to 3 and Comparative Example 1 were investigated. As a result, it was observed that the shadow mask of Comparative Example 1 had a pulling pack, and the periphery of the mask was depressed. On the other hand, the shadow masks of Examples 1 to 3 had good characteristics, with almost no springback phenomenon or less than that of the comparative example.

In addition, in Examples 1 to 3 and Comparative Example 1, test pieces were prepared by punching out the flat mask material before pressing,
The tensile strength and breaking strength of these test pieces were measured. As a result, the test pieces of Examples 1 to 3 had tensile strength and breaking strength of 2 kg/lIrm2, respectively, compared to the test piece of Comparative Example 1.
．． 15 kg/mpA2.1, 0 kg/kilometer decrease.

Furthermore, Nl-Fe containing 0.05% by weight of P in Example 2
When the state of the grain interior and grain boundaries of a sample of a flat mask material made from the alloy was investigated using an Auger electron spectrometer, the results shown in FIG. 3(a) #(b) were obtained. As shown in Figure 3, P is detected at the grain boundaries. Since P is below the detection limit within the grains, it is concluded that P is concentrated at the grain boundaries and causes grain boundary embrittlement. Recognize. In addition, almost the same results as in FIG. 3 were obtained in both Examples 1 and 3.

10- Example 4 A shadow mask was manufactured in the same manner as in Example 1 except that a Ni--Fe alloy containing 0.005% by weight of S was used.

Example 5 A shadow mask was manufactured in the same manner as in Example 1 except that an alloy consisting of 36% Nl-Fe containing 0.02% by weight of S was used.

Example 6 A shadow mask was manufactured in the same manner as in Example 1 except that an alloy consisting of 36% Ni-Fe containing 0.05% by weight of S was used.

Comparative Example 2 A shadow mask was manufactured in the same manner as in Example 1, except that an alloy consisting of 36% Ni-Fe containing 0.0005% by weight of S was used.

Therefore, the conditions of the shadow masks of Examples 4 to 6 and Comparative Example 2 were investigated. As a result, the shadow mask of Comparative Example 2 suffered from springback, and a phenomenon in which the periphery of the mask was depressed was observed. On the other hand, the shadow masks of Examples 4 to 6 had good characteristics with almost no springback phenomenon or less springback phenomenon than the comparative example.

Further, in Examples 4 to 6 and Comparative Example 2, test pieces were prepared by punching out the flat mask material before pressing, and the tensile strength and breaking strength of these test pieces were measured. As a result, the test pieces of Examples 4 to 6 had a tensile strength and a breaking strength of 2.0 kg/ph2.0, respectively, compared to the test piece of Comparative Example 2.
It had decreased by about 1.5 kg/■2.1, 0 kg/+m+1.

Example 7 36% Nl-F containing 0.005% by weight of Ag k
A le shadow mask was manufactured in the same manner as in Example 1 except that e-alloy was used.

Example 8 A shadow mask was manufactured in the same manner as in Example 1 except that a 36 q6Ni-Fe alloy containing 0.02% by weight of As was used.

Example 9 A shadow mask was manufactured in the same manner as in Example 1 except that a 36% Ni-Fe alloy containing 0.05% by weight of As was used.

Comparative Example 3 36% Ni-Fe containing 0.0005% by weight of Am
A shadow mask was manufactured in the same manner as in Example 1 except that an alloy was used.

Therefore, the conditions of the shadow masks of Examples 7 to 9 and Comparative Example 3 were investigated. As a result, the shadow mask of Comparative Example 3 suffered from springback, and a phenomenon in which the periphery of the mask was depressed was observed. On the other hand, the shadow masks of Examples 7 to 9 had good characteristics with almost no springback phenomenon or less than that of the comparative example.

In Examples 7 to 9 and Comparative Example 3, test pieces were prepared by punching out the flat mask material before pressing, and the tensile strength and breaking strength of these test pieces were measured. As a result, the test pieces of Examples 7 to 913- had tensile strength and breaking strength of 2.0 kg/m12 and 1.5 kg/III, respectively, compared to the test piece of Comparative Example 3.
I+2.1, 0kg had fallen by about 7m.

In addition, when shadow masks were manufactured using sb as the AsO material in Examples 7 to 9, the same results were obtained in Examples 7 to 9.
It was confirmed that it has similar excellent properties.

On the other hand, when an image was projected onto the color picture tube shown in FIG. 1 incorporating the shadow masks of Examples 1 to 9,
In both cases, stable images were obtained. In particular, since there is no depression around the shadow mask surface, the adhesion between the shadow mask 6 and the phosphor surface 5 is maintained, and the electron beam 11 passes through a desired mask hole and collides with the phosphor surface 5 accurately.

Such an effect is effective in a high-quality color picture tube with a mask hole diameter of about 0.2 tts, and a detailed image can be obtained.

Furthermore, the color picture tubes incorporating the shadow masks of Examples 1 to 9 all exhibited very low PD values of 90 μm or less. Furthermore, the color picture tube incorporating the shadow masks of Examples 1 to 9 is effective in preventing howling. What's more, color shifts do not occur even when subjected to momentary shocks, and the shadow mask has little vibration even when a large amount of sound waves in the audible low frequency range is applied, which prevents color shifts and image shaking. can.

〔Effect of the invention〕

As described in detail above, according to the present invention, the molding process which contains Ni-Fe as the main component and predetermined amounts of P, S, As, and Sb reduces springback by forming a shadow mask etc. with a good material. A color that can easily realize high-definition TV images where 'ease of viewing' is important, with a high-precision shadow mask without color shift and image blurring, and with a level of detail comparable to that of satellite broadcasting. A picture tube can be realized.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a color picture tube, Figure 2 is a 36
Figures 3(a) and 3(b) show the relationship between the amount of P added in the Ni-Fe alloy and the 0.2 inch proof stress after annealing. FIG. 2 is a diagram obtained by analyzing the state of the grains and grain boundaries in the sample using an Auger electron spectrometer. 1... Envelope, 3... Electron gun, 5... Fluorescent surface,
6... Shadow mask, 7... Frame, 9...
Inner shield, 11...Electronic heat. Applicant's agent Patent attorney Takehiko Suzue 16- Figure 1 0 0.1 0.2 Mu (Ka, 11) (Cao 31°mu)

Claims (4)

[Claims] (1) At least one member of the shadow mask, frame, and inner shield mainly contains F and N1, and contains 0.002 to 0.1% by weight of any of the elements phosphorus, sulfur, arsenic, and antimony. A color picture tube characterized in that it is made of a multi-layered material. (2) The collar according to claim 1, wherein at least one of the members is annealed so that the average element concentration at the polycrystalline grain boundary is higher than the average element concentration within the grain. Picture tube. (3) A color picture tube according to claim 1, characterized in that at least one of the members is formed of a material obtained by increasing the temperature to the austenite region in the Fe-Ni phase diagram. 0 (4) At least one of the members f, Fe-N
2. The color picture tube according to claim 1, wherein the color picture tube is made of a material that has been heated to an austenite region in the i-phase diagram and then aged in a region lower than that temperature.