CN109642289B

CN109642289B - Material for metal mask and method for producing the same

Info

Publication number: CN109642289B
Application number: CN201780052358.0A
Authority: CN
Inventors: 大森章博; 冈本拓也; 饭田恭之
Original assignee: Hitachi Metals Ltd
Current assignee: Proterial Ltd
Priority date: 2016-08-31
Filing date: 2017-08-31
Publication date: 2021-06-01
Anticipated expiration: 2037-08-31
Also published as: EP3508604A4; CN109642289A; WO2018043641A1; EP3508604A1; KR102200854B1; KR20190034263A; JP6807038B2; EP3508604B1; JPWO2018043641A1; KR102200854B9

Abstract

The invention provides a metal mask material which can inhibit the shape change after etching and has better etching property and a manufacturing method thereof. A material for a metal mask, wherein the surface roughness in the rolling direction and the surface roughness in the direction orthogonal to the rolling direction are both 0.05 [ mu ] m or more and Ra or less and 0.25 [ mu ] m or less, Rz or less and 1.5 [ mu ] m or less, and the skewness Rsk or less is 0 or less, wherein a sample having a length of 150mm and a width of 30mm is cut out from the material for a metal mask, and the sample is etched from one side, whereby the amount of warpage is 15mm or less and the plate thickness is 0.01mm or more and less than 0.10mm when 60% of the plate thickness of the sample is removed.

Description

Material for metal mask and method for producing the same

Technical Field

The present invention relates to a metal mask material and a method for manufacturing the same.

Background

For example, in the production of an organic-Electroluminescent (EL) display, a metal mask is used to generate a color pattern by vapor deposition on a substrate. In such a metal mask, as one of methods for forming the opening portion, a method of etching a thin plate of an Fe — Ni alloy is known. Various proposals have been made to improve the etching characteristics. For example, patent document 1 describes a material for etching, in order to form a high-definition etching pattern, the material being characterized by having a surface roughness Ra measured in a direction perpendicular to the rolling direction: 0.08 to 0.20 μm, and a surface roughness measured in the rolling direction of Ra: 0.01 to 0.10 μm, and has a surface roughness measured in a direction perpendicular to the rolling direction exceeding 0.02 μm in terms of Ra as compared with the surface roughness measured in the rolling direction, and has a rough surface roughness. Patent document 2 describes a metal mask material in which the etching properties are improved by adjusting the X-ray diffraction intensities of the crystal orientation (111), crystal orientation (200), crystal orientation (220), and crystal orientation (311) of the rolled surface.

Documents of the prior art

Patent document

Patent document 1: japanese patent application laid-open No. 2010-214447

Patent document 2: japanese patent laid-open No. 2014-101543

Disclosure of Invention

Problems to be solved by the invention

Patent document 1 is an invention in which etching characteristics are improved by adjusting the surface roughness Ra measured in the direction perpendicular to the rolling direction and the surface roughness Ra measured in the rolling direction, respectively, and patent document 2 is an invention in which etching characteristics are improved by adjusting the crystal orientation of the rolled surface. However, in order to produce a higher-definition organic EL display, it is necessary to form a high-precision pattern on a mask to be used, and accordingly, a material for a metal mask is required to have further improved etching properties. On the other hand, it is also desirable to adjust the residual stress in the material so that deformation such as warpage does not occur even in half etching (half etching) at various depths. The invention aims to provide a metal mask material which can inhibit the shape change after etching and has better etching property and a manufacturing method thereof.

Means for solving the problems

In order to achieve the above object, the present inventors have conducted active studies on various factors affecting an etching tool, such as a chemical composition, surface roughness, and residual stress. As a result, the present inventors have found that etching can be performed with higher accuracy and that a change in shape after etching can be greatly suppressed.

That is, one embodiment of the present invention is a material for a metal mask, which contains, in mass%, C: 0.01% or less, Si: 0.5% or less, Mn: 1.0% or less, Ni: 30 to 50 percent, the balance being Fe and inevitable impurities, wherein,

in the raw material for the metal mask, the surface roughness in the rolling direction and the surface roughness in the direction orthogonal to the rolling direction are respectively 0.05 mu m and Ra are less than or equal to 0.25 mu m, Rz is less than or equal to 1.5 mu m, skewness (skewness) Rsk is less than 0,

a sample having a length of 150mm and a width of 30mm is cut from the metal mask material, and the sample is etched from one side, and the amount of warpage is 15mm or less and the thickness is 0.01mm or more and less than 0.10mm when 60% of the thickness of the sample is removed.

Preferably: the skewness Rsk is more than-3.0.

Preferably: the difference between the skewness Rsk in the rolling direction of the metal mask material and the skewness Rsk in the direction orthogonal to the rolling direction is 0.7 or less.

Preferably: the difference between the surface roughness Ra of the metal mask raw material in the rolling direction and the surface roughness Ra of the metal mask raw material in the direction perpendicular to the rolling direction is less than 0.02 mu m.

Preferably: a sample having a length of 150mm and a width of 30mm is cut out from the metal mask material, and the sample is etched from one side, so that the amount of warpage is 15mm or less when any of 20%, 30%, and 50% of the thickness of the sample is removed.

Another embodiment of the present invention is a method for producing a material for a metal mask, including mixing, in mass%, a mixture of C: 0.01% or less, Si: 0.5% or less, Mn: 1.0% or less, Ni: a method for producing a metal mask blank, comprising cold-rolling a cold-rolling material containing 30 to 50% of Fe and the balance of unavoidable impurities to obtain a metal mask blank,

the conditions of the final pass (pass) of the finish cold rolling step for the cold rolling material are as follows: the reduction rate is as follows: 35% or less, roll bite angle: less than 1.0 degree,

in the raw material for metal mask, the surface roughness in the rolling direction and the surface roughness in the direction orthogonal to the rolling direction are respectively 0.05 μm or more and Ra or less and 0.25 μm or less, Rz or less and 1.5 μm or less, the skewness Rsk is less than 0, and

a sample having a length of 150mm and a width of 30mm is cut out from the metal mask material, the sample is etched from one side, the amount of warpage is 15mm or less when 60% of the thickness of the sample is removed,

the thickness of the material after finish cold rolling is 0.01mm or more and less than 0.10 mm.

Preferably: the nip angle of the rolls is less than 0.4 °.

Preferably: the reduction ratio of the final pass in the finish cold rolling step is 15% or less.

Preferably: the surface roughness Ra of the roller used in the final pass of the finish cold rolling step in the direction perpendicular to the circumferential direction (the rotation direction of the roller) is 0.05-0.25 [ mu ] m.

Preferably: the rolling speed in the finishing cold rolling step is more than 60 m/min.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention having the above features, a material for a metal mask which shows little change in shape after etching, little variation in etching, and excellent etching processability can be obtained.

Drawings

Is free of

[ description of symbols ]

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Detailed Description

The present invention will be described in detail below. However, the present invention is not limited to the embodiments described herein, and appropriate combinations and modifications may be made without departing from the scope of the technical idea of the present invention. The metal mask material of the present invention also includes a steel strip wound in a coil shape or a rectangular thin plate produced by cutting the steel strip.

The metal mask material of the present invention is a metal mask material containing, by mass%, C: 0.01% or less, Si: 0.5% or less, Mn: 1.0% or less, Ni: the reason for the chemical composition of Fe-Ni alloy, which is 30% to 50% and the balance Fe and unavoidable impurities, is as follows.

[ C: 0.01% by mass or less ]

C is an element having an influence on etching properties. Since the etching property is impaired if C is contained excessively, the upper limit of C is set to 0.01%. The lower limit is not particularly limited, since C may be 0% or more in the production steps.

[ Si: 0.5 mass% or less, Mn: 1.0% by mass or less ]

Si and Mn are generally used for deoxidation, and are contained in a trace amount in an Fe — Ni alloy, and if they are contained excessively, segregation is likely to occur, so Si: 0.5% or less, Mn: 1.0% or less. The preferred amounts of Si and Mn are Si: 0.1% or less, Mn: less than 0.5 percent. The lower limits of Si and Mn can be set to 0.05% for example, and 0.05% for Mn.

[ Ni: 30 to 50 mass% ]

Ni has an effect of adjusting a thermal expansion coefficient, and is an element having a large influence on low thermal expansion characteristics. If the content is less than 30% or exceeds 50%, the effect of lowering the thermal expansion coefficient is not exhibited any more, so that the range of Ni is 30% to 50%. The preferred Ni content is 32% to 45%.

The balance being Fe and unavoidable impurities.

First, the metal mask material of the present invention will be described.

(surface roughness)

The surface roughness of the metal mask material of the present embodiment is characterized in that the arithmetic average roughness Ra (in accordance with JIS-B-0601-2001) is 0.05 μm to 0.25 μm, and the maximum height Rz (in accordance with JIS-B-0601-2001) is 1.5 μm or less. By having Ra and Rz within the above ranges, the material of the present invention can be etched with high precision. When Ra exceeds 0.25 μm, the surface of the material becomes too rough, and therefore, variations occur in the progress of etching, and it becomes difficult to perform highly accurate etching. When Ra is less than 0.05 μm, the adhesiveness of the resist tends to be lowered. Even if the range of Ra is satisfied, it is not preferable that Rz exceeds 1.5 μm because a large peak portion in the roughness curve is formed in a part of the surface of the material, and etching from the peak portion causes etching unevenness. A more preferable upper limit of Ra is 0.13. mu.m, and a more preferable upper limit of Rz is 1.0. mu.m. The lower limit of Rz is not particularly limited, but if Rz is too low, the adhesiveness of the sheet-like resist may be lowered, and therefore, the lower limit of Rz is preferably set to 0.3 μm. In order to suppress local etching unevenness, it is preferable that the surface roughness satisfies both the surface roughness in the direction perpendicular to the rolling direction (hereinafter, also referred to as "width direction" or "rolling orthogonal direction") and the surface roughness in the rolling direction (hereinafter, also referred to as "longitudinal direction") of the metal mask material. Further, it is preferable to adjust the difference in Ra between the direction perpendicular to the rolling direction of the material and the rolling direction to less than 0.02. mu.m. This can suppress the progress unevenness of etching. In addition, a contact or non-contact roughness meter generally used can be used for measuring the surface roughness.

The material for a metal mask of the present embodiment is characterized in that the skewness Rsk (in accordance with JIS-B-0601-2001) is less than 0 in addition to the surface roughness. By satisfying the above numerical range, the roughness curve of the surface of the material has a wider peak portion than a valley portion, and thus etching can be performed more uniformly. Assuming that Rsk >0, the difference in etching progress between the peak portion and the bottom portion of the roughness curve tends to be large, but by making Rsk less than 0, etching unevenness can be further suppressed. This is more remarkable in a thin plate material in which etching is performed in a short time and the progress of etching is likely to become uneven. More preferably Rsk < -1.0. The lower limit of Rsk is not particularly limited, but a material having an excessively low Rsk is difficult to produce, and therefore, it is preferable to set the lower limit to about-3.0. The difference between Rsk in the rolling direction and width direction of the material is preferably 0.7 or less, more preferably 0.5 or less, and further preferably 0.2 or less. Here, Rsk in the present embodiment has a negative value in both the rolling direction and the rolling orthogonal direction. In addition, in order to sufficiently obtain the effect of Rsk and form a higher fine pattern, the material for a metal mask of the present embodiment is applied to a material having a thickness of less than 0.10 mm. The thickness is preferably less than 0.06mm, more preferably less than 0.03 mm. The lower limit is not particularly limited, but is set to 0.01mm because it is difficult to etch if it is too thin.

(amount of warping)

The material for a metal mask of the present embodiment is characterized in that a sample having a length of 150mm and a width of 30mm is cut out, and the sample is etched from one side, and the amount of warpage is 15mm or less when 60% of the thickness of the sample is removed. As described above, by reducing the residual stress, even if etching is performed in the vicinity of the center of the plate thickness where the stress is more unbalanced, deformation can be suppressed, and etching can be performed satisfactorily. Therefore, it is possible to cope with half etching at various depths, and thus it is possible to improve the degree of freedom of the etching pattern. The amount of warpage is preferably 15mm or less when any of 20%, 30%, and 50% of the thickness of the sample is removed. More preferably, the warpage is 15mm or less except for 20%, 30% or 50% of the thickness of the sample. The amount of warpage is preferably 13mm or less, more preferably 11mm or less, and further preferably 9mm or less. Most preferably: the stress is likely to be unbalanced and large warpage is likely to occur, and the amount of warpage when 50% of the thickness of the sample is removed is preferably 9mm or less, and the amount of warpage when 20% or 30% of the thickness of the sample is removed is preferably 6mm or less. In the present embodiment, the sample was cut so that the longitudinal direction of the cut sample became the rolling direction, and the warpage was measured. The warpage measurement method in the present embodiment is as follows: after the sample was removed by etching from one side, the cut sample (cut sample) was hung with the upper end thereof in contact with the vertical flat plate stage, and the horizontal distance between the lower end of the cut sample separated from the vertical flat plate stage by warping and the vertical flat plate stage was measured as the amount of warping.

Next, a method for manufacturing the metal mask material of the present embodiment will be described.

The manufacturing method of the present embodiment can be applied to, for example, the steps of vacuum melting, hot forging, hot rolling, and cold rolling. If necessary, homogenization heat treatment may be performed at about 1200 ℃ in the stage before cold rolling, and annealing at 800 to 950 ℃ may be performed at least once in the cold rolling step in order to reduce the hardness of the cold rolled material. In the cold rolling step, a grinding step for removing dirt (scale) on the surface or an edge wave (edge cut) step for removing an edge wave (edge wave) portion generated by removing an off-gage portion (portion of sheet thickness) at the end of the material and rolling may be performed. Although a known furnace such as a vertical furnace or a horizontal furnace (horizontal furnace) may be used as the furnace used in the heat treatment step, a vertical furnace in which deflection due to its own weight is less likely to occur is preferably used in order to prevent breakage during the plate transfer and to further improve the steepness (steepness) of the raw material.

In the manufacturing method of the present embodiment, the reduction ratio in the final pass of the finish cold rolling step is adjusted to 35% or less. When the reduction ratio exceeds 35%, the residual strain of the material becomes large, and the deformation tends to increase during the etching process. The upper limit of the reduction ratio is preferably 15%, more preferably 10%, and still more preferably 6%. If the reduction is too small, it becomes difficult to adjust the surface roughness, and slip (slip) between the rolling mill and the material becomes easy to occur, so the lower limit of the reduction can be set to 2%. The number of passes in finish cold rolling is not particularly limited, and the number of passes may be increased (for example, three or more, preferably four or more, and more preferably five or more) in order to prevent breakage or the like which is likely to occur when a thin material having a plate thickness of less than 0.1mm or the like is processed. The reduction ratio is preferably specified for all passes of finish cold rolling.

In the manufacturing method of the present embodiment, the surface roughness Ra of the roll used in the final pass of the finish cold rolling in the direction orthogonal to the circumferential direction of the roll (the rotation direction of the roll) is: a roller of 0.05 μm to 0.25 μm. The preferable upper limit of Ra is 0.15. mu.m. This can impart a desired roughness to the metal mask material. The material of the roll is not particularly limited, and for example, an alloy tool steel roll defined in JIS-G4404 can be used.

The system of the present embodimentIn finish cold rolling, the entry angle, which is the angle at which the material to be rolled and the work roll (work roll) start to contact each other, is set to less than 1.0 °. By adjusting the bite angle within the above numerical range, rolling oil is intentionally introduced between the material to be rolled and the work rolls, and the uneven portions on the surfaces of the work rolls are prevented from being excessively transferred to the material to be rolled. This reduces the difference between the surface roughness in the direction perpendicular to the rolling direction and the surface roughness in the rolling direction of the metal mask material, and tends to more reliably adjust Rsk to a negative value. Further, by introducing rolling oil between the work rolls and the rolled surface of the material, a material for a metal mask having a surface Rsk of the material adjusted to less than 0 and having more excellent etching workability can be obtained. When the Rsk is to be reliably adjusted to a negative value, the biting angle is preferably adjusted to less than 0.4 °. Here, if the biting angle is too small, there is a possibility that slippage, a shape adjustment failure, or the like may occur, and therefore, the lower limit may be set to 0.05 °. The above-described setting of the bite angle is preferably applied to all passes of finish cold rolling. When the biting angle of the present embodiment is θ, θ can be changed to 180/pi arccos ((R- (h))₀-h₁) The formula of/2)/R) is derived. Here, R: radius of the roller, h₀: thickness of raw material before rolling, h₁: the thickness of the rolled stock.

In the production method of the present embodiment, the rolling speed is preferably set to 60m/min or more. By setting the rolling speed to 60m/min or more, the rolling oil can be reliably introduced between the work rolls and the metal mask material, and oil pits (oil pits) for adjusting Rsk to a negative value can be more reliably formed. The lower limit of the rolling speed is more preferably 80 m/min. The upper limit of the rolling speed is not particularly set, but if it is too high, a large amount of rolling oil is introduced between the work rolls and the material, and a slip failure may occur, and therefore, for example, the upper limit may be set to 300 m/min.

In the manufacturing method of the present embodiment, strain relief annealing may be performed in order to remove strain remaining in the metal mask material after finish rolling and suppress a shape defect occurring in the material. The strain relief annealing is preferably performed at a temperature of about 400 to 700 ℃. The annealing time is not particularly limited, but is preferably about 0.5min to 2.0min because properties such as tensile strength are greatly deteriorated if the annealing time is too long, and the effect of removing strain cannot be obtained if the annealing time is too short.

Examples

The present invention will be described in more detail in the following examples.

The chemical composition of the metal mask material of this example is shown in table 1. The Fe — Ni alloy of the present example was subjected to cold rolling after the step of finishing to a thickness of 2mm to 3mm by vacuum melting, hot forging, homogenization heat treatment, and hot rolling. And (3) carrying out cold rolling including twice annealing on the Fe-Ni alloy after the hot rolling to manufacture the Fe-Ni alloy cold rolled material. The thicknesses of the Fe-Ni alloy cold rolled materials before the final pass of the finish cold rolling were 0.0208mm (sample No.1) and 0.054mm (sample No.2), and the rolling conditions were adjusted so that the thickness of sample No.1 after the finish cold rolling was 0.020mm (reduction ratio of 4%) and the thickness of sample No.2 after the finish cold rolling was 0.050mm (reduction ratio of 7%). The roll bite angle of sample No.1 at this time was 0.26 °, and the number of passes during finish rolling was seven. The roll bite angle of sample No.2 was 0.51 °, and the number of passes during finish rolling was four. In sample Nos. 1 and 2, the rolling speed in finish cold rolling was 80m/min on average. The roughness Ra of the roll used for finish cold rolling in the direction perpendicular to the circumferential direction (the rotational direction of the roll) is in the range of 0.05 to 0.2. mu.m. After finish cold rolling, strain relief annealing was performed at a temperature of 500 ℃ for 1 minute.

[ Table 1]

(mass%)

Sample No.	C	Si	Mn	Ni	The remaining part
						1	0.003	0.023	0.27	35.7	Fe and inevitable impurities
2	0.002	0.023	0.29	36.0	Fe and inevitable impurities

The surface roughness and warpage of the obtained sample were then measured. The surface roughness Ra, the surface roughness Rz, and the surface roughness Rsk were measured by selecting three portions at random according to the measurement methods shown in JISB0601 and JISB0651, and measuring the surface roughness in the longitudinal direction and the width direction. The measurement was carried out using a stylus type roughness meter under the conditions of an evaluation length of 4mm, a measurement speed of 0.3mm/s and a cut-off value of 0.8 mm. The average of the three sites is shown in table 2. The warpage was measured by preparing a sliced sample having a length of 150mm and a width of 30mm, etching the sliced sample from one side so as to have a thickness of 2/5 mm, measuring the warpage amount when the sliced sample was hung on a vertical plate platform, and evaluating the warpage amount. The sliced sample was extracted from the center in the width direction of the prepared sample so that the longitudinal direction thereof was the rolling direction. The etching solution was an aqueous solution of ferric chloride, and the test piece was etched by spraying the etching solution at a liquid temperature of 50 ℃. The results are shown in Table 2.

[ Table 2]

From the results of table 2, it can be confirmed that: the metal mask material of the present invention has a surface state optimal for exhibiting good etching workability, and can suppress a shape change after deep etching exceeding half of the plate thickness.

(example 2)

Next, a plurality of cut specimens of specimen No.1 having a length of 150mm and a width of 30mm were prepared, and the amounts of etching removed were changed as shown in Table 3 to specimen Nos. 3 to 5 of the present invention examples, and the amount of warpage was measured. The method for measuring the amount of warpage and the etching solution used were the same as those used in example 1. The results are shown in Table 3.

[ Table 3]

From the results of table 3, it was confirmed that: the material for a metal mask of the present invention can suppress the amount of warpage even if the etching depth is changed. In particular, when the amount of material removed by etching is 50% of the plate thickness, the compressive residual stress and the tensile residual stress are unbalanced, and excessive warpage tends to occur, but excessive warpage is not observed in the material of the present invention.

Claims

1. A material for a metal mask, comprising, by mass%, C: 0.01% or less, Si: 0.5% or less, Mn: 1.0% or less, Ni: 30 to 50 percent, the balance being Fe and inevitable impurities, wherein,

in the raw material for the metal mask, Ra is more than or equal to 0.05 mu m and less than or equal to 0.25 mu m in the surface roughness in the rolling direction and the surface roughness in the direction orthogonal to the rolling direction, Rz is more than or equal to 1.5 mu m in the maximum height, Rsk is less than 0,

2. The material for a metal mask as set forth in claim 1, wherein the skewness Rsk is-3.0 or more.

3. The material for a metal mask according to claim 1 or 2, wherein a difference between a skewness Rsk in a rolling direction of the material for a metal mask and a skewness Rsk in a direction orthogonal to the rolling direction is 0.7 or less.

4. The material for a metal mask according to claim 1 or 2, wherein a difference between a surface roughness Ra in a rolling direction of the material for a metal mask and a surface roughness Ra in a direction orthogonal to the rolling direction is less than 0.02 μm.

5. The material for metal masks according to claim 1 or 2, wherein a sample having a length of 150mm and a width of 30mm is cut out from the material for metal masks, and the sample is etched from one side, and the amount of warpage is 15mm or less when any of 20%, 30%, and 50% of the thickness of the sample is removed.

6. A method for producing a material for a metal mask, comprising the steps of mixing, in mass%, a mixture of C: 0.01% or less, Si: 0.5% or less, Mn: 1.0% or less, Ni: a method for producing a metal mask blank, comprising cold-rolling a cold-rolling material containing 30 to 50% of Fe and the balance of unavoidable impurities to obtain a metal mask blank,

in the finish cold rolling step for the cold rolling material, the conditions of the final pass are as follows: the reduction rate is as follows: 35% or less, roll bite angle: less than 1.0 degree,

in the raw material for the metal mask, Ra is 0.05 μm or more and Ra is 0.25 μm or less in the rolling direction and Ra is 0.05 μm or less in the direction orthogonal to the rolling direction, Rz is 1.5 μm or less in the maximum height, Rsk is less than 0, and

7. The method for manufacturing a raw material for a metal mask as set forth in claim 6, wherein a bite angle of said roll is less than 0.4 °.

8. The method of manufacturing a raw material for a metal mask as set forth in claim 6 or 7, wherein a reduction ratio of a final pass in the finish cold rolling step is 15% or less.

9. The method of manufacturing a material for a metal mask as set forth in claim 6 or 7, wherein a surface roughness Ra of a roller used in a final pass of the finish cold rolling step in a direction orthogonal to a circumferential direction is 0.05 μm to 0.25 μm.

10. The method of manufacturing a material for a metal mask as set forth in claim 6 or 7, wherein a rolling speed in the finish cold rolling step is 60m/min or more.