JPH07116558B2 - Fe-Ni alloy thin plate for shadow mask and method for manufacturing the same - Google Patents

Description

The present invention relates to a Fe—Ni alloy thin plate for a shadow mask and a method for manufacturing the same, and Fe-for manufacturing a shadow mask for a color television cathode ray tube. It relates to a technology for obtaining an appropriate product by excellent etching piercing property in a Ni-based alloy thin plate, particularly preventing unevenness during piercing, and preventing adhesion baking when annealing a flat mask after piercing ( (Prior Art) Fe-Ni is used as a shadow mask material with low thermal expansion that can cope with the problem of color misregistration as color televisions become higher in quality in recent years.
Inverter alloys of the series have been attracting attention, but this alloy is more likely to produce unevenness in the flat mask during etching perforation and adhesion bakeability when the flat mask after perforation is annealed, as compared with conventional shadow mask materials made of low carbon steel. Is remarkable.

Among these, in order to solve the former problem, JP-A-61-
39344, JP-A-62-243780, and 243781.
No. 243782 and No. 243782 are proposed.

That is, the surface roughness (center line average roughness Ra) of the shadow mask material is set to 0.1 to 0.4 μm to obtain the regularity of the aperture shape and the uniformity of the aperture in the entire shadow mask. Or the surface roughness (R
a) 0.2 to 0.7 μm, Sm (average value of the unevenness of the cross-sectional curve showing the surface roughness within the standard length) is 100 μmn or less, and the grain size is 8.0 or more in terms of grain size number. We offer high-quality masks. Further, in addition to the above-mentioned regulation, Re (transmission hole diameter α ₁ / etching hole diameter α ₂ ) is set to 0.9 or more to provide a mask having high unevenness after etching perforation. Note that the texture of the etching material is integrated by strong cold rolling-recrystallization annealing, and the crystal grain size is 8.0 or more in the grain size number, and then the surface roughness described above is adjusted to the cold workability by the dull roll. It is intended to manufacture a mask with high unevenness after etching perforation with 3 to 15%.

On the other hand, no preferable proposal has been made to solve the latter problem described above.

That is, contact adhesion during annealing of a conventional low carbon steel flat mask as disclosed in JP-A-62-238003 is optimized for surface roughness, that is, Ra is 0.2 to 2.0 μm and Rsk (in the height direction of the roughness curve is The strength of Fe-Ni Invar alloy is higher than that of low carbon steel, and the annealing temperature before curved surface pressing is higher than that of low carbon steel, even if there is a proposal to make the index of deviation) 0 or more. Inevitably, it is necessary to use a high temperature, and since several tens to several hundreds of sheets are stacked and annealed at a considerably high temperature of 800 to 1100 ° C, this low carbon steel flat mask technology uses Fe-Ni. Since it is impossible to prevent adhesion and seizure during annealing in a flat mask of a system-based Invar alloy, there is no preferable technique for preventing such seizure.

Further, in JP-A-64-52022, alloy components such as Si, cold rolling rate, and grain size are specified.
In No. 252725, heat treatment for homogenizing the slab was performed and
It is disclosed that the uneven streaks are suppressed by reducing the segregation.

(Problems to be Solved by the Invention) None of the above-mentioned techniques for improving the uneven quality of the flat mask at the time of etching perforation achieves the prevention of adhesion seizure in the annealing before the curved surface pressing. In addition, as mentioned above, only the conventional adhesion prevention during low carbon steel flat mask annealing is prevented, the actual Invar alloy strength is higher than that of low carbon steel, and the annealing temperature before the curved surface press is low. It is inevitable to use it higher than in the case of carbon steel, and cathode ray tube manufacturers have to stack dozens to several hundreds of flat mask annealing of Fe-Ni Invar alloys.
The present condition is that the temperature is 0 to 1100 ° C, which is considerably higher than the annealing temperature of the low carbon steel flat mask. At such an annealing temperature, the above-mentioned technique cannot prevent seizure during the Invar alloy flat mask annealing.

Since the above-mentioned things are not considered in terms of surface texture and adhesion seizure prevention, occurrence of unevenness and seizure is unavoidable,
However, it is the extent to reduce the segregation of Ni at most,
It is not possible to properly obtain the prevention of sticking seizure and the prevention of seizure in relation to surface properties.

Therefore, in the conventional Fe—Ni-based Invar alloy shadow mask material, no technique has been established for preventing unevenness during etching perforation and for appropriately preventing adhesion baking during annealing after perforation.

“Structure of the Invention” (Means for Solving the Problems) In view of the above-mentioned circumstances, the present invention has excellent etching perforation properties, particularly prevents unevenness during perforation, and anneals a flat mask after perforation. Fe that prevents sticking and burning
-To obtain a Ni-based Invar alloy shadow mask material,
It was created through repeated studies and is as follows.

(1) Contains Si: 0.01 to 0.15 wt% and Ni: 34 to 38 wt%,
The balance consists of Fe and unavoidable impurities, and the plate thickness of the alloy steel strip is substantially the same as the flat mask used in the production of a shadow mask including a step of stacking and annealing a number of flat masks, Surface roughness (Ra)
Is 0.3 to 0.7 μm, and the skewness (Rsk), which is a deviation index in the height direction of the roughness curve, is 0.3 to 1.0,
and, Of the composition of Si on the surface of the alloy plate just before etching Fe for shadow masks characterized by less than 10%
-Ni alloy thin plate; (2) It has the component and surface roughness of (1) above, and the anisotropy of the surface roughness is expressed by the following formula: | Ra (L) -Ra (c) | ≦ 0.1 μm. | Rsk (L) −Rsk (c) | ≦ 0.2 where Ra (L) and Rsk (L) are measured values in the rolling direction, and Ra (c) and Rsk (c) are measured in the direction perpendicular to the rolling direction. It is a value.

Fe for shadow masks characterized by satisfying the relationship
-Ni alloy thin plate; (3) In producing a thin plate having the component of (1), a dull roll is used at the time of final cold rolling or temper rolling, and the surface roughness of (1) is applied to the surface of the thin plate. A method for producing an Fe-Ni alloy thin plate for a shadow mask, which is characterized by applying: (4) In producing a thin plate having the component (1), a dull roll is used at the final cold rolling or temper rolling, A method for producing an Fe-Ni alloy thin plate for a shadow mask, which comprises imparting the surface roughness of (2) to the surface of the thin plate.

(Operation) To explain the present invention as described above, the present invention is directed to an Invar alloy for a shadow mask, but the average thermal expansion coefficient (30 to 30
The upper limit of (100 ℃) is 2.0 × 10 ^-6 / ℃, and the thermal expansion property is N
It depends on the amount of i, and the component range that satisfies the above-mentioned average thermal expansion coefficient is wt (hereinafter simply referred to as%), and the amount of Ni is
Since it is 34 to 38%, the Ni content of the alloy of the present invention is 34 to 38%. The Ni content is appropriately selected within the above range according to the required thermal expansion coefficient.

Next, the target of the present invention is the etching property and the prevention of adhesion and seizure during flat mask annealing, by optimizing the surface roughness and
It is achieved only when the Si content and its distribution optimization are satisfied at the same time. That is, Si is an element effective in preventing adhesion seizure during annealing in Fe-Ni-based Invar alloy.
When it is more than 0.1%, an oxide film effective for preventing the seizure is formed. On the other hand, if this Si exceeds 0.15%, unevenness during etching perforation becomes significant, so this is set as the upper limit, and from these, seizure can be prevented, and the amount of Si without unevenness during etching perforation is set to 0.01 to 0.15%. It was Even if the amount of Si is in this range, if the variation in the composition of Si on the surface of the alloy plate is large, there will be differences in the properties of the oxide film formed during annealing or local unevenness caused by the difference in the etching perforation state. ,
As a result, a problem such as local image sticking occurs, and such component fluctuations must be controlled. Therefore, in the present invention, in addition to the regulation of the above Si amount, the component segregation ratio of Si on the alloy plate surface immediately before etching, By setting the ratio to 10% or less, it is possible to solve the local deterioration of the etching piercing property and the local baking during annealing due to the above component fluctuation. It should be noted that, even if the composition ratio of Si is 10% or less, it is less than 0.01% in the minimum concentration part, or 0.15 in the maximum concentration part.
If it exceeds%, baking during annealing and unevenness during etching perforation respectively occur, so control is performed to prevent this.

In order to prevent the seizure during annealing and suppress the occurrence of unevenness during etching perforation, which is the intended purpose of the present invention, it is necessary to optimize the surface roughness in addition to the above-mentioned component regulation. That is, Fig. 1 shows that S ≥ 0.0025%, Si: 0.01 to 0.15% (Si 0.01 to 0.15% at any place in the plate surface), and the component segregation ratio of si ≤ 10%
The alloy plate of No. 1 was investigated for etching perforation property and adhesion seizure during annealing, and the regions satisfying both of them were shown by surface roughness parameters Ra and Rsk. R
Regardless of the value of sk, if Ra exceeds 0.7 μm, unevenness during etching and perforation becomes remarkable, while Ra is 0.
If it is less than 3 μm, adhesion baking during flat mask annealing occurs on the entire surface, and uniform adhesion failure of the flat mask occurs, so the Ra range in the present invention is 0.3 to 0.7 μm.
And

In addition to such optimization of Ra, optimization of Rsk is also necessary to prevent seizure during annealing. That is, Ra is 0.3 to 0.7
Even in the μm range, if Rsk is less than +0.3, adhesion occurs during flat mask annealing over the entire surface, while Rsk is +1.0.
If it exceeds, local seizure occurs during flat mask annealing. Also, under the condition of Ra <-1 / 3Rsk + 0.5, adhesion occurs during flat mask annealing over the entire surface.

From the above, as the conditions of the surface roughness for obtaining the effect intended by the present invention, Ra: 0.3 to 0.7 μm, Rsk: 0.3 to 1.0 and (R
a) -1/3 (Rsk) + 0.5.

As described above, by optimizing the Si amount and its distribution and optimizing the surface roughness, it is possible to prevent the adhesion perforation during etching perforation and annealing when the Fe-Ni Invar alloy is applied to a thin plate for a shadow mask. However, in order to reduce the cost during annealing by increasing the number of laminated flat masks in one annealing more than before, in addition to the above surface roughness regulation, the surface roughness The anisotropy within should be below a specific value. That is, by setting the surface roughness anisotropy to | Ra (L) −Ra (c) | ≦ 0.1 μm | Rsk (L) −Rsk (c) | ≦ 0.2, the number of stacked flat masks is increased compared to the conventional case. Even when doing, partial seizure can be avoided.

In addition, in order to increase the critical temperature at which adhesion baking does not occur during annealing of the flat mask, it is effective to reduce S in addition to the above-described components and surface roughness regulation. Figure 2 shows Ra, Rs
The state of adhesion baking was investigated by changing the annealing temperature using a material having k, Si and Si segregation ratios within the range of the present invention and varying the S content. By reducing the amount of S, the critical annealing temperature at which seizure does not occur can be increased.

Although a clear mechanism of the effect of the reduction of S is not clear, the formation of an oxide film of Si which is effective in preventing adhesion formed on the surface of the Invar alloy having a Si content within the scope of the present invention during press annealing, It is speculated that the surface segregation of S may occur due to competition with the surface.

As means for reducing the segregation of Si, for example, a steel ingot or a continuous cast (CC) slab is heated at 1200 ° C for 20 hours, and 1
Slab rolling is performed at a cross section reduction rate of 20 to 60% in the secondary slab, the light slab is heated at 1200 ° C for 20 hours, and slab rolling is performed at a cross section reduction rate of 30 to 50% in the secondary slab. Then, the process of slow cooling can be mentioned. In this process, reduction of Si ingot segregation by primary heating and soaking, processing in primary slab and subsequent reduction of steel ingot segregation and micro segregation by heating and soaking, and secondary slumping The homogenization of Si is achieved for the first time by the synergistic effect of homogenization in three major steps, namely further promotion of reduction of steel ingot segregation and microsegregation of Si in the processing and subsequent slow cooling process. In addition,
The heating before lumping suppressed the S content in the atmosphere to 80 ppm or less as much as possible to suppress the grain boundary embrittlement during heating, and considered the generation of surface defects in the lumped slab.

Further, the thin plate for a shadow mask, which is a feature of the present invention, is not limited to the one having the above-mentioned manufacturing history, and strip casting for casting a cold rolled material directly from molten steel or a steel strip cast by strip casting is subjected to hot rolling and light rolling. By doing so, the effect of the present invention can be sufficiently exhibited even in the case where the cold-rolled material is manufactured. The production of the Invar alloy material for a shadow mask having such a surface can be achieved by rolling with a dull roll during final cold rolling or temper rolling.

In order to improve the etching perforation property of the amber alloy, especially the quality of the hole interface after the etching perforation, and to reduce the contamination of the etching solution in the etching process and to improve the workability of etching, the non-metal in the alloy is used. The composition of the inclusions should be the composition outside the region enclosed by the pentagon connecting points 1, 2, 3, 4, and 5 in the Al ₂ O ₃ —CuO—MgO system three-dimensional phase diagram shown in FIG. It is necessary to control. That is, by controlling the composition of such inclusions, non-metallic inclusions immediately before etching are mainly spherical inclusions having a size of 3 μm or less, and there are very few linear inclusions that have extensibility and extend in the rolling direction. As a result, the formation of pits due to the inclusions at the interface of the etching holes is suppressed, and the linear inclusions are hardly mixed with the etching liquid and are contaminated with the etching liquid.

To obtain the above-mentioned dull roll, electric discharge machining, laser machining or the like may be adopted, but it is preferable to make dull weight by the shot blasting method, and in this case, SKH (hardness Hs85 to 95) is adopted as the roll material, Also diameter 1
It is appropriate to use one with a diameter of 00 to 125 mm. # 120 ~ # 2 as roll processing conditions by shot blasting method
40 steel grit (Hv400 ~ 950) is used, and the projection energy is low at # 120 and high at # 240.

To obtain the proper roll surface roughness, Ra0.1
Ra: when processed to a value of less than μm (Rsk <0)
0.4 to 1.0 μm, Rsk: <−0.2, more preferably <−0.5, and the surface roughness within the range of the present invention can be appropriately obtained as such roll roughness.

Regarding rolling, the final cold rolling or temper rolling uses 10% or more for each pass with a dull roll as described above, and a total of 2 or more passes is adopted, and the roll roughness is reduced by 10% or more for each pass. Is sufficiently transferred, and the predetermined Rsk can be effectively obtained by using two or more passes.

Further, as a rolling oil used at the time of concrete rolling, one having a temperature of 10 to 50 ° C. and a viscosity of 7 to 8 cst is discharged at a rate of 0.1 to 0.5 kg / cm ² and used, a rolling speed is 30 to 200 mpm, and a tension during rolling is front 15～45Kg / mm ^2, preferably in the 0.15 to 0.25 t / mm is a rear 10～40Kg / mm ² degree and without, as rolling force per unit width. The rolling oil discharge pressure described above is less than 0.1 kg / cm ² , or more than 0.5 kg / cm ² the surface roughness of the alloy thin plate targeted by the present invention tends to be difficult to obtain even if other conditions are appropriate, or If it exceeds 0.5 kg / cm ² , uneven surface roughness will occur. Further, by adjusting the tension conditions during rolling as described above, the flatness of the alloy thin plate as a rolled material can be made to be a good level.

Ironing rolls, anti-clean pink rolls, etc. are used for rolling thin sheets, and continuous annealing furnaces for mild steel (H ₂ concentration 5 to 15%, DP-10 to -30 ° C atmosphere gas) for intermediate annealing and SR annealing. Or bright annealing furnace (H ₂ concentration 15-100%, DP
-20 to -50 ° C) and the like are used.

(Examples) The specific examples of the present invention as described above will be shown, and the details of the operation and effects thereof will be described below.

Example 1 Alloys Nos. 1 to 5 of the present invention and comparative examples having the composition as shown in Table 1 below are tapped in an electric furnace and then ladle refining is performed to produce a 7 ton steel. Obtained as a lump.

For ladle refining after tapping, a ladle made of MgO-CaO refractory with CaO: 40% or less is used, and the slag is composed of wt% (Ca
O) / [(CaO) + (Al ₂ O ₃ )] 0.45% or more, MgO 25%
Hereinafter, SiO 15% or less, the weak metal oxides oxidizing power than Si is one of the CaO-Al ₂ O ₃ -MgO based 30% or less,
By processing with this, the chemical composition in Table 1 and the alloy as shown in Table 2 described later were obtained.

After caring for each steel ingot obtained as described above, 1200
Heat at 20 ° C for 20 hours, lump-roll at the primary agglomeration at a cross-section reduction rate of 60%, then heat at 1200 ° C for 20 hours, then slab-roll at a secondary lump at a cross-section reduction rate of 45%. Then, by slowly cooling, the test materials a, c to f were obtained from alloy No. 1 and alloy No. 2
Is a sample material g, alloy No. 3 is a sample material h, alloy No. 4 is a sample material i, and alloy No. 5 is a sample material P. The material of co-test material b is 1200 ° C after caring for a 7-ton ingot of alloy No.1.
A slab was prepared by heating for 15 hours, slab rolling with a primary slab at a cross-sectional reduction rate of 78%, and slow cooling.

These slabs were cared for, coated with an antioxidant, heated at a heating temperature of 1100 ° C., and then hot rolled. At this time, the total rolling reduction at 1000 ° C or higher is 82%, the total rolling reduction at 850 ° C or higher is 98%, and the winding temperature of the hot rolled hot rolled coil is 550 to 750 ° C. Met.

Of the hot rolled coils obtained as described above, alloy No. 1
~ No. 4 corresponds to the plate thickness having the surface roughness shown in Table 3 described later by repeating cold rolling and annealing after descaling and rolling with a dull roll during final cold rolling or temper rolling. 0.25 mm alloy plates were obtained respectively. The morphology and size of the inclusions in the etching test material were measured by measuring the plate thickness section in the rolling direction of the original plate. The measuring method is 800 times 6
0mm ² Specimen, measure the thickness and length of all the inclusions in the field of view, (length / thickness) ≤ 3 are spherical inclusions, (length / thickness)
> 3 was classified as linear inclusions and indicated by the number of these inclusions (per 1 mm ² ).

The material used for the rolls used is a shot blasting method
SKH (Hs90) roll with a diameter of 120 mm is processed with # 120 steel grit (Hv400 to 950), and the surface roughness after processing is
Ra: 0.3 to 0.85, Rsk: -0.2 to -1.1 rolls were used. In this example, the first pass was 18.6% due to the dull roll at the time of final temper rolling, and the second pass was 12.3% (total reduction ratio was 28.6%. The rolling oil used for this rolling had a viscosity of 7.5 cst, a rolling speed of 100 mpm, and a rolling tension of 20 kg / mm ² forward and 15 kg / mm ² backward.

The rolling force per unit width used in this rolling was 0.20 ton / mm, the discharge pressure of the rolling oil was 0.4 kg / cm ² , and the rolling process could be carried out smoothly. The flatness and the like could be obtained at a good level.

The segregation ratio of Si on the plate surface of each alloy plate as described above is EPMA.
It was investigated by a mapping analyzer by. Further, these alloy thin plate coils were perforated by etching to prepare flat masks, and the occurrence of unevenness was investigated. Further, the interface of the etching hole was observed by a scanning electron microscope to check for the presence of pits, and the contamination of the etching solution was checked by checking the amount of residue after the etching perforation. Further, regarding the adhesion baking at the time of annealing, 30 pieces of the above flat masks were laminated and an adhesion state was investigated after annealing at a temperature of 900 ° C. Each of the alloy Nos. 1 to 5 has a composition of inclusions as shown in Table 2 below, and the inclusions have a liquidus temperature of 16
It has a melting point of 00 ° C or more, and the inclusions in the alloy thin plate just before etching are spherical in shape and 3μm or less in terms of size and thickness. The pits at the pore interfaces are not seen, and the contamination of the etching solution is extremely small, and the etching property is excellent.
That is, as the alloy material intended in the present invention, a material having such excellent etching piercing property is basically used.

The results of each of the above-mentioned investigations are shown in Table 3 below, and the alloy Nos. 1 to 5 are shown in FIG.
In the ternary phase diagram of the Al ₂ O ₃ -CaO-MgO system, it is shown as ~.

That is, the materials of the test materials a and g are Si amount, Si segregation ratio, Ra
(L), Ra (c), Rsk (L), Rsk (c), (Ra) +1/3
All the values of (Rsk) are within the range of the present invention, and neither unevenness during etching perforation nor adhesion baking during annealing is observed.

On the other hand, for the test materials h, i, b, although the parameters of the surface roughness are all within the range of the present invention, the amount of Si falls below the lower limit of the present invention, and its upper limit is set. Or the segregation rate exceeds the upper limit,
Problems are recognized in one or two of unevenness occurring during etching perforation and adhesion baking during annealing.

In each of the test materials c, d, e, and f, the amount of Si and the segregation ratio of Si are within the specified range of the present invention, but the upper limit of Ra in the present invention, (Ra) +1/3 ( Rsk) -0.5, the lower limit of Rsk, and the upper limit of Rsk, which are unfavorable for one or more of unevenness during etching perforation and adhesion bakeability during annealing.

That is, it is understood that the effect aimed at by the present invention can be achieved only by optimizing the surface roughness in addition to the component consideration such as the amount of Si and the segregation ratio of Si.

Example 2 The hot-rolled coil used for producing the test material a, the hot-rolled coil used for production of the test material p, and the hot-rolled coil used for production of the test material g of Example 1 were described above. After descaling, cold rolling and annealing are repeated, and final rolling or temper rolling is performed using a dull roll, and an alloy sheet having a surface roughness of 0.25 mm as shown in Table 4 below (test material j, k, l, m, n, p and o)
Got

The Si segregation rate on the plate surface of each of these test materials was examined by the same method as in Example 1, but all were in the range of 2 to 7%. In addition, these alloy thin plate coils were punched by etching to produce flat masks, and the occurrence of unevenness was investigated. Further, the adhesion baking during annealing is performed by stacking 50 of the above flat masks
After annealing at the temperature shown in the table, the adhesion state after that was examined. All of these results are shown in Table 4 below.

The dull roll and rolling conditions used in this example are the same as those described in Example 1 above, but the surface roughness of the roll is Ra:
0.45 to 0.70 μm, Rsk: −0.4 to −0.9.

That is, in the sample material j, the Si content, the Si segregation ratio, and the surface roughness are all within the ranges specified by the present invention, and the S content is 0.0005%.
No unevenness was generated during etching perforation, and no adhesion baking occurred even under the annealing conditions of this example.

On the other hand, the test material o has Si content, Si segregation rate, and surface roughness within the stipulated range of the present invention, and S content of 0.0025%. In some cases, adhesion baking during annealing occurs. As described above, even when the constituent requirements of the present invention are satisfied, the annealing temperature is set to the value of Example 1
It is understood that when the temperature becomes higher, the amount of S can be lowered to prevent the occurrence of adhesion baking.

Furthermore, the test material p has a Si content, a Si segregation rate, and a surface roughness within the specified ranges of the present invention, and an S content of 0.0002%,
There is no unevenness during etching perforation, and the annealing temperature is higher than that of the test material j, but no adhesion baking occurs. By reducing the amount of S in this way, 1100
It is clear that even at a high temperature of 0 ° C, the prevention of adhesion sticking is achieved.

In addition, the test material n is within the specified range of the present invention except for the in-plane anisotropy of Ra and the in-plane anisotropy of Rsk. Adhesion seizure did not occur in annealing. On the other hand, the test material m is a case where the flood mask of the test material n is annealed at 950 ° C. In this case, the adhesion baking during the annealing occurs over the entire surface.

Note that each of the test materials k and l also falls within the specified range of the present invention except for the in-plane anisotropy of Ra and the in-plane anisotropy of Rsk, and these materials can be annealed at 950 ° C. Adhesion sticking is partially generated. With respect to these test materials k, l, and m, all of the test material j, including the in-plane anisotropy of Ra and the in-plane anisotropy of Rsk, are within the scope of the present invention. In this case, even if the annealing temperature was 950 ° C, no adhesion baking occurred.

Even with a material that does not cause annealing adhesion at 850 ° C., it is necessary to optimize the in-plane anisotropy of Ra and Rsk when increasing the annealing temperature.

"Effects of the Invention" According to the present invention as described above, excellent etching piercing property, also accurately prevent occurrence of unevenness at the time of piercing, and adhesion baking in annealing the flat mask after piercing. Providing a thin plate for a shadow mask of Fe-Ni-based Invar alloy that is also appropriately prevented, and obtaining a preferable manufacturing method to manufacture a high-quality flat mask with a high yield, thereby enabling cost reduction. It is an invention that has a large effect industrially.

[Brief description of drawings]

The drawings show the technical contents of the present invention. FIG. 1 is a table showing the relation between Ra, Rsk and the occurrence of unevenness during etching perforation in a flat mask and the adhesion bakeability during annealing. charts the relationship between the annealing adhesion and S of the flat mask shows the case of 30 sheets annealed at a flat mask lamination, FIG. 3 is a ternary phase diagram of CaO-Al ₂ O ₃ -MgO based nonmetallic inclusions FIG. 4 is a ternary phase diagram showing the general relationship, which is a part, and shows alloy Nos. 1 to 5 used in the embodiment of the present invention as FIG. is there.

Continuation of the front page (56) References JP 62-238003 (JP, A) JP 61-39344 (JP, A) JP 62-243782 (JP, A)

Claims (4)

[Claims] 1. Si: 0.01 to 0.15 wt%, Ni: 34 to 38 wt% and
Mn: containing 0.40 wt% or less, the balance consisting of Fe and unavoidable impurities, and the plate thickness of the alloy steel strip is used for the production of a shadow mask including a step of stacking and annealing a number of flat masks. It is substantially equivalent to a flat mask, its surface roughness (Ra) is 0.3 to 0.7 μm, and its skewness (Rsk), which is an offset index in the height direction of the roughness curve, is 0.3 to 1.0, and Segregation rate of Si on the surface of the alloy plate just before etching Fe for shadow masks characterized by less than 10%
-Ni alloy thin plate. 2. The composition according to claim 1 and the surface roughness, and the anisotropy of the surface roughness is expressed by the following formula: | Ra (L) −Ra (c) | ≦ 0.1 μm | Rsk (L ) −Rsk (c) | ≦ 0.2 where Ra (L) and Rsk (L) are measured values in the rolling direction, and Ra (c) and Rsk (c) are measured values in the direction perpendicular to the rolling direction. Fe for shadow masks characterized by satisfying the relationship
-Ni alloy thin plate. 3. In producing a thin plate having the components of claim 1, a dull roll is used during the final cold rolling or temper rolling to impart the surface roughness of claim 1 to the surface of the thin plate. And a method for manufacturing an Fe-Ni alloy thin plate for a shadow mask. 4. When producing a thin plate having the components of claim 1, a dull roll is used during the final cold rolling or temper rolling to impart the surface roughness of claim 2 to the surface of the thin plate. And a method for manufacturing an Fe-Ni alloy thin plate for a shadow mask.