TW404984B - Fe-Ni alloy materials for shadow masks - Google Patents

Abstract

Provision of Fe-Ni alloy materials for shadow masks capable of controlling the development of banded nonuniformity defects on etching. In an Fe-Ni alloy consisting of 30 to 55 wt% Ni and the balance Mn, Fe, and unavoidable impurities, the Mn contents restricted to 1.0 wt% of less and the contents of Si and P as unavoidable impurities to 0.05 wt% or less and 0.01 wt% or less, respectively, and the component concentration difference of Ni in the micro-segregated portions in the cross section of the alloy material for etching is 3 % or less, the component concentration differences of Si, Mn, and P in the point where the component concentration difference of Ni is measured are 0.02 % or less, 0.1 % or less, and 0.002 % or less, respectively. The component concentration difference between Si, Mn, or P or their combination and Ni in the same point is preferably within the designated range. The Ni concentration difference in the Ni segregated portions and the component concentration differences of Si, Mn, and P that coexist in those portions are thus controlled to inhibit the development of parallel bands.

Description

Central Bureau of Standards, Ministry of Economic Affairs, Shellfish Consumer Cooperation, Du printed 404984 V. Description of Invention () [Field of the Invention] The present invention relates to a shadow mask material processed by precision etching, and in particular a shadow mask Iron-nickel alloy material, which contains 30 to 55% by weight of nickel, and is adjusted to control the development of band unevenness on the surrounding wall of the hole, which is precisely etched in a shadow mask To pass through the electron beam. [Background of the Invention] In recent years, shadow masks for color video tubes have been manufactured using an iron-nickel alloy with a low thermal expansion coefficient called "36 alloy" because of its color purity. Generally, the shadow mask is punctured by etching to form holes for electron beams to pass through. In particular, the hole is usually formed by forming a plurality of circular openings on one side of the shadow mask blank, such as a photoresist mask with a circular hole of 80 m in diameter, and a circular opening is formed at a corresponding point on the other side. For example, a photoresist mask with a circular hole with a diameter of 1 80 Pm, and then spraying water on the sides with ferric chloride. Moreover, it has recently been discovered that, compared with the traditional shadow masks of steels that have been treated to reduce oxygen (kild steel), iron-nickel alloy etching will produce defects called "band unevenness" in the holes. Surrounding walls. In the case of an iron-nickel alloy, it is known from Japanese Patent Application Publication No. 60 to 5 6 ◦ 5 3 that the band-like nonuniformity reflects the segregation phenomenon of nickel and is caused by the part of the nickel that is segregated and the base metal. Differences in stability between the two have produced arbitrary irregularities in the shape of the holes. The segregated portion of nickel, as shown in Figure 2, has a linear band shape

1123.DOC This paper size is in accordance with Chinese National Standard (CNS) A4 (210X297 mm) (Please read the notes on the back before filling out this page) 4 ° Ding — Work and Consumer Cooperation of Central Standards Bureau of the Ministry of Economic Affairs, printed 404984 A7 B7 V. Description of the invention () 1 (referred to as "band structure"), etched on the cross section of the alloy material with ferric chloride solution or 5% nitric acid alcohol solution known as "Nital". The extension of the separated part of the medium is the result of rolling. The boundary between the separated part and the base metal 闾 can be sharply increased in the X-ray intensity map and grasped clearly. The non-uniformity of the bands in the hole array can be confirmed by guiding the beam through the holes inclined from the back to the front along the rolling direction, and the entire inspection of the band-shaped beams parallel to each other in the rolling direction is reflected on the wall of the hole And shoot out from the hole to see if there is a difference in intensity between the strip-shaped rays in the rolling direction. In particular, the band unevenness reflects the lack of uniformity of the hole walls in the hole rows and columns in the width of the hole shadow mask blank (that is, perpendicular to the rolling direction). This can be confirmed when the rolling direction has different band-shaped beam intensities and are parallel to each other. The beam is reflected on the hole wall and exits from the hole when the beam is inclined and guided from the back to the front. Its reflection on the hole wall is along the rolling direction. . When there is no non-uniformity on the walls in the hole array of the hole shadow mask blank width direction, because the beam has the same intensity after reflecting from each wall of the hole in the width direction, the band pattern will not be seen . When the wall characteristics of a row of holes in the width direction of the hole shadow mask blank are different from those of other rows, the intensity of the light reflected from the wall of this special hole in the width direction is different from the rest, so the emitted light is a band Shape pattern.

1123.DOC This paper size applies to China National Standard (CNS) A4 specification (21 × X 297 mm) I --------- ^ ------- rfr --_---- ^ (Please read the precautions on the back before filling out this page.) Consumer Co-operation of the Central Standards Bureau of the Ministry of Economic Affairs, printed 404984. V. Description of the Invention () Discussion on the prevention of the formation of band unevenness has been mentioned by the aforementioned patent application announcement number 6 0 — 5 6 0 5 3 Yes. This discussion is based on the fact that the formation of band-like unevenness can be slowed down by reducing the segregation percentage of the nickel segregation part (the benchmark for the nickel content in the base metal), that is, reducing {(the component concentration in the average composition concentration of the segregation part) / (Average component concentration) 丨 number of X 1 0 0. From this point of view, it is recommended to limit the percentage of segregation to 10% or less, the percentage of segregation of the entire unit volume to 5% by volume or less, and the length of each segregation part is directly etched to 3 Omm or less. In addition, Patent Application Publication No. 4-7 4 850 proposes to prevent the occurrence of non-uniformity during etching perforation. The percentage of silicon element segregation in the surface of the alloy plate during etching should be limited to 10% at most. [Objective of the Invention] The recent trend in shadow masks is toward higher hole densities or smaller hole distances between electron beams, and the problem arises that finer band-like unevenness develops more than before. However, none of the known perforation techniques can satisfactorily control the fine band unevenness and there is still a demand for improvement in this respect. According to previous observations, the object of the present invention is to provide an iron-nickel alloy material of a shadow mask, which can suppress the development of band unevenness during etching, and includes the above-mentioned fine band shape. [Summary of the Invention] In order to understand this object, the present inventors have made extensive research and obtained the following new findings. The band unevenness is actually caused by the concentration of 1123.DOC 6 This paper's paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) (Please read the precautions on the back before filling this page) -Pack_ 1T Printed by the Central Bureau of Standards, Ministry of Economic Affairs, Consumer Cooperatives 404984 V. Description of the invention () The steps of forming an etching change in the surrounding wall of the electron beam hole. The formation of the concentration step is related to the difference in the element concentration of nickel in the nickel fractionation part; the smaller the difference in the concentration of nickel elements, the smaller the frequency of step formation. In addition, some examples show that band-like unevenness may occur even when the difference in nickel element concentration is small. This phenomenon also occurs when there are differences in elemental concentrations of silicon, manganese, and phosphorus in the nickel fractionation part. In particular, it is obvious that the factor that affects the development of the band-like non-uniformity on the wall of the tiny electron beam hole is the difference in element concentration in the segregation part instead of the generally considered percentage of segregation; in order to prevent the The development of the non-uniformity of the shape not only needs to limit the difference in the nickel concentration in the nickel segregation part, but also the difference in the concentration of one of the three elements silicon, manganese, and phosphorus at least within a certain range; The degree of uniformity varies with the elemental concentration of silicon, manganese, and phosphorus and the difference in nickel concentration. Β Although silicon, manganese, and phosphorus appear in what form, and whether nickel or a solid solution is formed in the alloy substrate The mixture is not terrible, but it can be known that the difference in element concentration of these elements, regardless of the form, emphasizes the difference in etching caused by the difference in nickel concentration. The description of the "nickel concentration difference" here means that, as shown in Fig. 1, the peak of the nickel concentration change curve (according to the X-ray analysis (EMPA) X-ray intensity change curve) 値 (where the nickel concentration is very high) High) and the adjacent valleys (where the nickel concentration is very low) are measured in the thickness direction of a linear strip (called a "ribbed structure"), with water-like ferric chloride or 5% nitrogen Alcoholic solution called acid Nital is hungry in the cross-sectional area of the alloy material. 1123.DOC 7 IIIIIU _ ~~ Order (please read the precautions on the back before filling this page) The standard of this paper applies the Chinese National Standard (CNS) A4 specification (2丨 0X297mm) A7 404984 V. Description of the invention () becomes visible after the moment. The difference in elemental concentration from silicon, manganese, and phosphorus means that the difference in concentration is measured at the same point where the difference in the concentration of nickel element is measured. Based on the above findings, the present invention provides: (1) an iron-nickel alloy material of a shadow mask, which contains 30 to 55 wt% of nickel and its balanced manganese, iron, and unavoidable impurities , Its characteristic is that the content of manganese is limited to 1 ♦ 0 wt% or less and unavoidable impurities such as silicon and phosphorus are controlled to 0. 05 wt% or less and 0. 0 1 wt% or less, respectively, and The difference in elemental concentration of nickel is 3% or less in the cross section of the alloy material used for etching in the differential solidification portion, and the difference in elemental concentration of silicon is 0 · 0 or less at the point where the difference in elemental concentration of nickel is measured. A preferable range of the element concentration difference at the same point as that of nickel is expressed by the following formula (1). Silicon concentration difference S 1.5 X 1 (^ / nickel concentration difference) (1) The present invention also provides: (2) an iron-nickel alloy material of a shadow mask, which contains 30 to 55% by weight of nickel and its Balanced manganese, iron, and unavoidable impurities. Its characteristics are that the content of manganese is limited to 1.0 wt% or less, and unavoidable impurities such as silicon and phosphorus are controlled to 0. 05 wt% or less. 〇 · 〇1 wt% or less, and the difference in elemental concentration of nickel is 3% or less in the cross section of the alloy material used for etching in the micro-coagulation part, and the difference in elemental concentration of manganese is measured in the difference in elemental concentration of nickel The point is 0 · 1% or 1123.DOC 8 I -i —-l ·-I ------1 I 1-. I ^ ”. -1---. (Please read the first Note: Please fill in this page again.) Printed by the Central Consumers ’Bureau of the Ministry of Economic Affairs, the Consumer Cooperatives. The paper size is applicable to the Chinese National Standard (CNS) A4 (210X 297 mm)-Λ r 404984 Λ7 B7 Employees’ consumption of the Central Standards Bureau Printed by the cooperative V. Description of the invention (Small, the preferred range of element concentration differences between manganese and nickel at the same point is given by the following formula (2 ) Indicates ° Manganese concentration difference S7_5: < 10 Nickel concentration difference (2) (3) Shadow-masked iron-nickel alloy material 'contains 30 to 5 5 wt% nickel and its balanced manganese' Iron 'and unavoidable impurities have the characteristic that the content of the bell is limited to 1.0 wt% or less, and unavoidable impurities such as Miao and Ne are controlled to ◦ 5 wt% or less and 〇. 〇 respectively. lwt% or less, and the difference in elemental concentration of nickel is 3% or less in the cross section of the alloy material used for etching in the microcoagulation portion, and the difference in elemental concentration of phosphorus is measured at the point where the difference in elemental concentration of nickel is measured. · 〇2 ° / b or less, the preferred range of elemental concentration difference between phosphorus and nickel at the same point is expressed by the following formula (3). Phosphorus concentration difference S1.5XHT3 / nickel concentration difference (3) where silicon Any two elements such as manganese, manganese, and phosphorus will appear, and each element is under the above restrictions of those two elements. Considering nickel on the one hand, and silicon, manganese, and phosphorus as a whole, the present invention further provides : (4) The iron-nickel alloy material of the shadow mask contains 30 to 55 wt% Fractional nickel and its balanced manganese, iron, and unavoidable impurities

18030.DOC This paper size applies Chinese National Standard (CNS) Λ4 specification (210X297 mm) 1 ^ 1 II--mi ^ n I 4 ^ * ^^^ 1 — nm I — ^ ϋ pounds,-· * l 』 (Please read the notes on the back before filling out this page) 4049 printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs Inevitable impurities such as silicon and phosphorus are controlled to 0.05 wt% or less and 0.01 wt% or less, respectively, and the difference in elemental concentration of nickel is in the cross section of the alloy material used for etching in the differentially solidified portion. 3% or less, and the difference in elemental concentrations of silicon, manganese, and phosphorus at the point where the elemental concentration difference of nickel was measured were 0.22% or less, 0 · 1% or less, and 0 · 0 0 2% or less, and the range of the elemental concentration difference between the entire combination of silicon, manganese, and phosphorus and nickel at the same point is expressed by the following formula (4). (10 X silicon concentration difference + manganese concentration difference + 100 X phosphorus concentration difference) S 0.3 / nickel concentration difference (4) [Brief description of the drawing] FIG. 1 is a diagram illustrating the definition of the element concentration difference. Figure 2 is an example of the nickel segregation on the etched surface. [Detailed explanation of the present invention] As described above, the present invention is mainly aimed at controlling the development of band-shaped non-uniformity during etching. Differences in element concentrations and the coexistence of elemental silicon, manganese, and phosphorus in the nickel segregation portion of iron 30 to 55 wt% nickel alloy materials. This material has low thermal expansion characteristics and is made into a shadow mask. The reasons for the limitation of the composite elements under this invention will be explained here. (A) Manganese content in the material

1123.DOC ______ 10 This paper music scale is appropriate (CNS) A4 specifications (21 ^ 297 ^ 7 --------- ^ --- J ---'- order ·-: ---- β (Please read the notes on the back before filling in this 1) A7 B7 404984 V. Description of the invention () The content of manganese is greater than 1.0 Wt% will reduce the thermal expansion characteristics of the material. Therefore, the upper limit of the content of fierce is 1. 0 wt%, preferably 0.35 wt%. (B) The silicon content in the material is greater than ◦ · 0.5 wt% silicon content will greatly reduce the material's etchability β. Therefore, the upper limit is 0.5 wt. %, Preferably 0.03 wt%. (C) Phosphorus content in the material exceeding 0. 0 1 wt% will also damage the material's etchability. Therefore, the upper limit is 0.01 wt%, Preferably, it is 0.05 wt%. (D) Difference in element concentration in the differential condensing part The difference in element concentration in the differential condensing part results in the formation of a concentrated step on the wall around the hole, in which the electron beam is Development through the hole. In order to avoid this phenomenon, the difference in nickel concentration in the microcoagulation part must be less than 3% or less, preferably 2% or less. Any difference in the concentration of elemental, fierce, or phosphorus If accompanied by nickel at the same time, the development of band-like non-uniformity will be stimulated in the nickel fractionation part. The upper limit of the element concentration difference varies with individual elements and also varies with the nickel concentration. Extensive experiments were conducted It is shown that the upper limit is set by the following method. If any two elements of silicon, manganese, and phosphorus appear, each element is restricted to the lower limit. If three elements coexist, there are different restrictions, respectively. Because they accelerate the development of band-like non-uniformities. As used herein, "nickel concentration difference" means that, as shown in Figure 1, the nickel concentration change curve (according to X-ray analysis (E PMA) X-ray intensity) Change curve) at peaks (where concentrations are high) and adjacent valleys

1123.DOC This paper size is in accordance with Chinese National Standard (CNS) A4 specification (210X297 mm) (Please read the precautions on the back before filling this page) Binding '· Printed by the Central Consumer Samples Bureau, Ministry of Economic Affairs, Consumer Cooperative 404984 V. DESCRIPTION OF THE INVENTION The largest difference between () (where the concentration is very low) is also measured in the thickness direction of a linear strip (known as < 'strip structure "), when aqueous ferric chloride is used Or 5% nitric acid called Nital alcohol solution becomes visible after etching in the cross-section direction of the alloy material. The description of "difference in elemental concentration of silicon, manganese, and phosphorus" means that this concentration difference is in the elemental concentration of nickel The difference is measured at the same point measured. Silicon concentration difference: 0 · 0 2 Wt% or less Manganese concentration difference: 0 · 1 wt% or less Phosphorus concentration difference: 0 · 0 0 2 wt% or less ( (Please read the notes on the back before filling this page) t% Silicon concentration difference S 1.5 X 10_2 / Nickel concentration difference (1) Manganese concentration difference S 7.5 X 104 / Nickel concentration difference (2) Phosphorus concentration difference S 1.5 X 10 · 3 / nickel splash difference (3) X 1 n,, -r ^ ^, ground ^ _ 1 〇0 / Concentration difference (10X silicon concentration difference + manganese concentration difference + printed by Shelley Consumer Cooperative, Central Standards Bureau of the Ministry of Economic Affairs) $ 0 · 3 / nickel concentration difference (4 The composite control of this specification can be described Lai Zhi {When the material is dissolved, the industry's manufacturing tools are used in the same way-carbon-low-pure iron and bribes. The lion content is combined by Pu Qingqing's flaps.赖 赖 赖 ## To solve the problem. To reduce 1123.DOC 12 This paper size applies to the national standard (CNS) A4 size (210 X 297 mm) of 117 countries. The Central Consumers Bureau of the Ministry of Economic Affairs and Consumer Cooperation Du printed 404984 A7 B7 V. Description of the invention () Low impurity concentration, dissolving treatment removes carbon, sulfur, phosphorus, and other impurities. As guided by the patent application Kokai No. 60-56053, the uneven development of the band is reduced by reducing the nickel content. The percentage of the basic content of nickel in the solidification part in the base metal is delayed, or it can be achieved by reducing the following number: ((element concentration in the fractionation part-average element concentration) / (average element concentration)) X 1 0 0. From this perspective, it is necessary to limit segregation The fraction ratio is 10% or less, the percentage of segregation of the entire unit volume is 5% by volume or less, and the length of each segregation part is 30 mm or less before etching. The manufacturing method is to achieve these The requirements include avoiding the phenomenon of segregation when the metal block is made, especially the method of using electromagnetic agitation during casting and micro-ventilation casting. [Example] Next, the example of the present invention will be compared and explained with a comparable example. First, the chemically synthesized iron-36% nickel alloy block in Table 1 was obtained by hollow dissolution. When the metal is dissolved, the industrial manufacturing method uses ordinary low-carbon, low-phosphorus pure iron and pure nickel. The manganese content was adjusted by the addition of mirror iron. Dissolution methods can be atmospheric dissolution and externally refined | and # instead of empty dissolution. It is appropriate to reduce the impurity concentration by such a treatment procedure to remove carbon, sulfur, and phosphorus. The metal block is then forged and hot-pressed. After repeated pressing and sintering, an alloy block of thickness 0.13 mm was obtained. To change the difference in element concentration, the heating of the metal block before forging is adjusted to 1 15 0 — 1 3 5 〇1123.DOC 13 IIIIIIIIII | Order 'II line (Please read the precautions on the back before filling this page) This paper The scale applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs 404984-V. Description of the invention () The temperature range of ° C and lasts 5 to 30 hours. The alloy bar samples 1 to 8 obtained in this way are examples satisfying the requirements of the present invention, and samples 9 to 15 are comparative examples. The extent to which band-like unevenness is formed in these alloy bars will be compared. For this purpose, a well-known photoengraving technology is used to form an impedance mask with multiple circular openings on one side of each shadow mask blank. The diameter of the opening is 80 # m and the mask on the other side has the same Number of circular openings, the opening diameter of which is 180 ° m. Spray the aqueous solution of ferric chloride on both sides of the photoresist to create a penetrating hole in the blank. The shadow mask formed in this way is supported by the small-diameter side facing the front guide and the light beam passes obliquely from the back to the front, so it can be observed that the parallel light beams are parallel to each other in the rolling direction. Each alloy bar is then etched with water-soluble ferric chloride in the transverse direction across the rolling direction, at three ends, respectively at the ends and in the middle. Ten portions were selected from the important linear separation bands observed in each region, and the difference in the concentration of a single element was found from the concentration change curve of the portion in the thickness direction of the sheet. (How to find the concentration change can be found in Figure 1.) The results of these examples and comparative examples are summarized in Table 1. The results in Table 1 show that none of the samples 1 to 8 can meet every requirement of the present invention and recognize the development of band unevenness. Compared with the above sample, sample 9 shows band unevenness. The reason is that the difference in nickel concentration exceeds 3%, which does not meet the specific relationship between the difference in nickel concentration and the elemental concentration of silicon and manganese. The latter 1123.DOC 14 This paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X 297 mm) ^ .------ IT -—; ---- ^ (Please read the precautions on the back before filling (This page) A 7 404984 B7 5. The difference in the description of the invention () can be very small. Samples 10 to 14 had a very small difference in nickel concentration, but were unable to meet the requirements of any of the silicon, manganese, and phosphorus element concentration differences in the present invention. They can therefore develop band-like unevenness. Sample 15 meets the requirements for differences in elemental concentration of silicon, manganese, and phosphorus and nickel concentration. However, it still forms a slight band unevenness because it does not establish the difference in nickel concentration and the entire silicon, manganese, and phosphorus. The required relationship between the combination of element concentration differences. This typical result allows us to determine that the development of band inhomogeneity can be completely ruled out by differences in elemental concentrations of silicon, manganese, and phosphorus that occur with nickel among the characteristics of the specified alloy material. --------- Equipment --- factory—Γ t— 一 ---- line (please read the precautions on the back before filling out this page) The Central Department of Standards, Ministry of Economic Affairs, Consumer Consumption Du printed U23. DOC ”This paper size is applicable to Chinese countries (210χ 297_ ^ τ \ 404984 Μ B7 V. Description of the invention (

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X 〇〇〇〇〇〇f6 6 This paper size is applicable to the Chinese national standard (0, 5) and 6 specifications (2 丨 0 '/; 297 mm) 404984 A7 B7 V. Description of the invention ([Advantages of the invention] Positive As described above, the present invention often has a brain county, and its assistant at the Jingzhong Carving Iron Industry Intersection also blows 7 swollen Td_alloy blanks to create shadows on the road. =====! Compared with bribes, the high-precision shadows and mouth-brushing materials can be penetrated to a greater density and have a greater distance between holes and holes. --------- 装 — (Please read first Note on the back of the item, fill in this page) ir. ~ ^ ---- Printed by the Shellfish Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 17

1123.DOC This paper uses the Chinese National Standard (CNS) Α4 size (210X297 mm)

Claims (1)

fl Μ Printed Bulletin by the Central Labor Bureau of the Ministry of Economic Affairs and Consumer Cooperatives 404984 g __, D8 VI. Patent Application Range 1 · An iron-nickel alloy material for shadow masks, containing 30 to 40 wt% nickel and more The amount is manganese, iron, and unavoidable impurities, which is characterized by the content of manganese limited to 0.5wt% or less and the content of silicon and phosphorus of unavoidable impurities is controlled to 0.05wt% or less and 0.005wt%, respectively. Or less, and the difference in elemental concentration of nickel is 2% or less in the differential solidification portion of the cross section of the alloy material used for etching, and the difference in elemental concentration of silicon, manganese, and phosphorus is measured at the point of difference in elemental concentration of nickel, respectively 0.02% or less, 0.1% or less, and 0.002% or less; and the point where the difference in elemental concentration of silicon in the measurement of the difference in elemental concentration of nickel falls within the range of formula (1) S1.5X10 · 2 / Nickel concentration difference (1); where the difference in elemental concentration of manganese falls within the range of formula (2) at the point where the difference in elemental concentration of nickel is measured falls within the range of formula (2) S7.5X10々 difference in nickel concentration (2); Elemental concentration difference in nickel The difference in phosphorus concentration S1.5XUT3 / nickel concentration difference (3) that falls within the range of formula (3); where the elemental concentration difference of silicon, manganese, and phosphorus is measured at the point where the elemental concentration difference of nickel falls in formula (4) Within the range (10 X silicon concentration difference + manganese concentration difference + 100 X phosphorus concentration difference) $ 0.3 / nickel concentration difference (4). --------------- ^ ------------ 0 (Please read the notes on the back before writing this page)-. This paper size applies to China National Standard (CNS) A4 now available (210X297 mm)