JP2002206105A - Method for manufacturing tantalum powder, tantalum powder, and tantalum electrolytic capacitor - Google Patents
Method for manufacturing tantalum powder, tantalum powder, and tantalum electrolytic capacitorInfo
- Publication number
- JP2002206105A JP2002206105A JP2000241612A JP2000241612A JP2002206105A JP 2002206105 A JP2002206105 A JP 2002206105A JP 2000241612 A JP2000241612 A JP 2000241612A JP 2000241612 A JP2000241612 A JP 2000241612A JP 2002206105 A JP2002206105 A JP 2002206105A
- Authority
- JP
- Japan
- Prior art keywords
- heat treatment
- tantalum powder
- temperature heat
- tantalum
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 title claims abstract description 128
- 229910052715 tantalum Inorganic materials 0.000 title claims abstract description 39
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- 238000000034 method Methods 0.000 title claims abstract description 8
- 239000003990 capacitor Substances 0.000 title claims description 19
- 238000010438 heat treatment Methods 0.000 claims abstract description 67
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims abstract description 26
- 239000011734 sodium Substances 0.000 claims abstract description 26
- 229910052708 sodium Inorganic materials 0.000 claims abstract description 26
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000011777 magnesium Substances 0.000 claims abstract description 20
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 20
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims abstract description 18
- 239000011591 potassium Substances 0.000 claims abstract description 16
- 229910052700 potassium Inorganic materials 0.000 claims abstract description 16
- 238000005554 pickling Methods 0.000 claims abstract 2
- NROKBHXJSPEDAR-UHFFFAOYSA-M potassium fluoride Chemical compound [F-].[K+] NROKBHXJSPEDAR-UHFFFAOYSA-M 0.000 claims description 50
- 239000011698 potassium fluoride Substances 0.000 claims description 26
- 235000003270 potassium fluoride Nutrition 0.000 claims description 26
- 150000003839 salts Chemical class 0.000 claims description 25
- 238000005245 sintering Methods 0.000 claims description 15
- 238000005406 washing Methods 0.000 claims description 3
- 239000003929 acidic solution Substances 0.000 claims description 2
- 239000000843 powder Substances 0.000 abstract description 16
- 239000002253 acid Substances 0.000 abstract description 3
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 12
- 239000002245 particle Substances 0.000 description 10
- 230000002776 aggregation Effects 0.000 description 9
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 8
- 238000004220 aggregation Methods 0.000 description 8
- 230000015572 biosynthetic process Effects 0.000 description 8
- 230000006835 compression Effects 0.000 description 7
- 238000007906 compression Methods 0.000 description 7
- 238000006722 reduction reaction Methods 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 6
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 6
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 6
- 239000000395 magnesium oxide Substances 0.000 description 6
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 6
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 6
- NUJOXMJBOLGQSY-UHFFFAOYSA-N manganese dioxide Chemical compound O=[Mn]=O NUJOXMJBOLGQSY-UHFFFAOYSA-N 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- 239000001301 oxygen Substances 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 6
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 6
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 5
- 239000007864 aqueous solution Substances 0.000 description 5
- 239000008188 pellet Substances 0.000 description 5
- 229910052698 phosphorus Inorganic materials 0.000 description 5
- 239000011574 phosphorus Substances 0.000 description 5
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 4
- 238000002484 cyclic voltammetry Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 238000000921 elemental analysis Methods 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 238000000465 moulding Methods 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 239000011148 porous material Substances 0.000 description 4
- 238000004438 BET method Methods 0.000 description 3
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 3
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 3
- COERJHDMQUPDCV-UHFFFAOYSA-N [K].FB(F)F Chemical compound [K].FB(F)F COERJHDMQUPDCV-UHFFFAOYSA-N 0.000 description 3
- 230000002378 acidificating effect Effects 0.000 description 3
- 229910052796 boron Inorganic materials 0.000 description 3
- 150000001639 boron compounds Chemical class 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 238000005345 coagulation Methods 0.000 description 3
- 230000015271 coagulation Effects 0.000 description 3
- JKWMSGQKBLHBQQ-UHFFFAOYSA-N diboron trioxide Chemical compound O=BOB=O JKWMSGQKBLHBQQ-UHFFFAOYSA-N 0.000 description 3
- 238000007865 diluting Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910017604 nitric acid Inorganic materials 0.000 description 3
- 239000011775 sodium fluoride Substances 0.000 description 3
- 235000013024 sodium fluoride Nutrition 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 230000018044 dehydration Effects 0.000 description 2
- 238000006297 dehydration reaction Methods 0.000 description 2
- 239000008151 electrolyte solution Substances 0.000 description 2
- AMWRITDGCCNYAT-UHFFFAOYSA-L hydroxy(oxo)manganese;manganese Chemical compound [Mn].O[Mn]=O.O[Mn]=O AMWRITDGCCNYAT-UHFFFAOYSA-L 0.000 description 2
- 238000005470 impregnation Methods 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 2
- 239000000155 melt Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 239000001103 potassium chloride Substances 0.000 description 2
- 235000011164 potassium chloride Nutrition 0.000 description 2
- 239000011164 primary particle Substances 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 239000011163 secondary particle Substances 0.000 description 2
- 230000006641 stabilisation Effects 0.000 description 2
- 238000011105 stabilization Methods 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 239000011882 ultra-fine particle Substances 0.000 description 2
- DSSYKIVIOFKYAU-XCBNKYQSSA-N (R)-camphor Chemical compound C1C[C@@]2(C)C(=O)C[C@@H]1C2(C)C DSSYKIVIOFKYAU-XCBNKYQSSA-N 0.000 description 1
- 241000723346 Cinnamomum camphora Species 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 229910020312 KCl—KF Inorganic materials 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- BNZSIHASOJXAMG-UHFFFAOYSA-N [NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[F-].[F-].[F-].[F-].[F-].[F-].[O-]P([O-])([O-])=O Chemical compound [NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[NH4+].[F-].[F-].[F-].[F-].[F-].[F-].[O-]P([O-])([O-])=O BNZSIHASOJXAMG-UHFFFAOYSA-N 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 229910052810 boron oxide Inorganic materials 0.000 description 1
- 229960000846 camphor Drugs 0.000 description 1
- 229930008380 camphor Natural products 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 229920001940 conductive polymer Polymers 0.000 description 1
- 238000007739 conversion coating Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- HTUMBQDCCIXGCV-UHFFFAOYSA-N lead oxide Chemical compound [O-2].[Pb+2] HTUMBQDCCIXGCV-UHFFFAOYSA-N 0.000 description 1
- 229910000464 lead oxide Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007784 solid electrolyte Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
- H01G9/00—Electrolytic capacitors, rectifiers, detectors, switching devices, light-sensitive or temperature-sensitive devices; Processes of their manufacture
- H01G9/004—Details
- H01G9/04—Electrodes or formation of dielectric layers thereon
- H01G9/048—Electrodes or formation of dielectric layers thereon characterised by their structure
- H01G9/052—Sintered electrodes
- H01G9/0525—Powder therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B34/00—Obtaining refractory metals
- C22B34/20—Obtaining niobium, tantalum or vanadium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/04—Making non-ferrous alloys by powder metallurgy
- C22C1/045—Alloys based on refractory metals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
- B22F2998/10—Processes characterised by the sequence of their steps
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、タンタル粉末の製
法、タンタル粉末およびタンタル電解コンデンサに関
し、特に比静電容量が８万〜２５万μＦＶ／ｇの高容量
のタンタル粉末が得られるようにしたものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing tantalum powder, a tantalum powder and a tantalum electrolytic capacitor, and more particularly to a method for obtaining a high-capacity tantalum powder having a specific capacitance of 80,000 to 250,000 .mu.FV / g. Things.
【０００２】[0002]
【従来の技術】電解コンデンサ用タンタル粉末を製造す
る方法については、特公平２−４６４１号公報に開示さ
れたものがある。この製法は、フッ化タンタル酸カリウ
ムをナトリウムで還元し、得られた還元タンタル粉末を
洗浄、乾燥したのち、減圧下に１２５０℃〜１５５０℃
で高温熱処理し、ついでマグネシウムを添加し、減圧下
に８００〜１０００℃で低温熱処理し、酸洗いするもの
である。2. Description of the Related Art A method for producing tantalum powder for electrolytic capacitors is disclosed in Japanese Patent Publication No. 2-4641. In this production method, potassium fluoride tantalate is reduced with sodium, and the obtained reduced tantalum powder is washed and dried, and then, under reduced pressure, at 1250 ° C. to 1550 ° C.
, Heat-treated at 800 to 1000 ° C. under reduced pressure, and then pickled.
【０００３】この製法にあっては、比静電容量（ＣＶ）
が１５０００μＦＶ／ｇ程度までのタンタル粉末を製造
するには好適な方法であるが、ＣＶが８万μＦＶ／ｇ以
上のタンタルを製造するには不適切であることが判明し
た。In this manufacturing method, the specific capacitance (CV)
Is a suitable method for producing tantalum powder up to about 15000 μFV / g, but it has been found that it is inappropriate for producing tantalum having a CV of 80,000 μFV / g or more.
【０００４】すなわち、ＣＶが８万μＦＶ／ｇ以上のタ
ンタル粉末を製造するには、基本的には還元タンタル粉
末が、微細で、表面積が大きくなければならない。この
ような微細な還元タンタル粉末に１２５０〜１５５０℃
の高温熱処理を施すと、温度が高すぎて粉末粒子の凝集
が適度に進行し、その表面積が減少してしまう。また、
高温熱処理後のタンタル凝集体が固くなり、その粉砕が
困難となる。また、低温熱処理時の温度も、微細な還元
タンタル粉末にはやはり高すぎ、これによっても同様の
理由によりその表面積が減少することがある。That is, in order to produce a tantalum powder having a CV of 80,000 μFV / g or more, basically, the reduced tantalum powder must be fine and have a large surface area. 1250-1550 ° C. for such fine reduced tantalum powder
When the high-temperature heat treatment is performed, the temperature is too high, the agglomeration of the powder particles proceeds appropriately, and the surface area decreases. Also,
The tantalum aggregate after the high-temperature heat treatment becomes hard, and its pulverization becomes difficult. Also, the temperature during the low-temperature heat treatment is still too high for the fine reduced tantalum powder, which may also decrease the surface area for the same reason.
【０００５】また、実際のタンタル電解コンデンサは、
得られたタンタル粉末を加圧成形して成形体とし、これ
を焼結して焼結体とし、ついでこの焼結体に化成酸化処
理を施して陽極体とし、これに二酸化マンガンを含浸
し、表面にカーボンを被覆することによって製造され
る。８万μＦＶ／ｇ以上の高ＣＶのタンタル電解コンデ
ンサを得るには、単にタンタル粉末の性状のみならず、
焼結体の焼結条件等にも影響を受けることが明らかにな
ったが、上記先行発明にはかかる知見についての開示は
ない。Further, an actual tantalum electrolytic capacitor is:
The obtained tantalum powder was pressed and formed into a compact, which was sintered to form a sintered body.Then, the sintered body was subjected to chemical oxidation treatment to form an anode body, which was impregnated with manganese dioxide, It is produced by coating the surface with carbon. In order to obtain a tantalum electrolytic capacitor having a high CV of 80,000 μFV / g or more, not only the properties of tantalum powder but also
It has been clarified that the sintering conditions are affected by the sintering conditions of the sintered body, but the above-mentioned prior invention does not disclose such knowledge.
【０００６】[0006]
【発明が解決しようとする課題】よって、本発明におけ
る課題は、ＣＶが８万〜２５万μＦＶ／ｇのタンタル粉
末を得るための還元タンタル粉末から焼結体に至るまで
の製造上の必要条件を明確にし、最終的にＣＶが８万〜
２５万μＦＶ／ｇ以上の高ＣＶを達成可能なタンタル粉
末が得られるようにすることにある。SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a manufacturing condition from a reduced tantalum powder to a sintered body for obtaining a tantalum powder having a CV of 80,000 to 250,000 μFV / g. And finally CV is 80,000 ~
An object is to obtain a tantalum powder capable of achieving a high CV of 250,000 μFV / g or more.
【０００７】[0007]
【課題を解決するための手段】本発明のタンタル粉末の
製法は、フッ化タンタル酸カリウムをナトリウム還元
し、得られた還元タンタル粉末を不活性雰囲気下で高温
熱処理する高温熱処理工程と、高温熱処理工程後のタン
タル凝集体を粉砕し、これにマグネシウムを添加し、減
圧下で低温熱処理を行う低温熱処理工程と、酸性溶液で
これを洗浄する酸洗工程を有するタンタル粉末の製法に
おいて、高温熱処理工程を１０００℃以上、１２５０℃
未満の温度で行い、低温熱処理工程を７００℃〜１００
０℃の温度で行うことを特徴とする。上記製法において
は、フッ化タンタル酸カリウムをナトリウムで還元する
際、フッ化タンタル酸カリウムとナトリウムとをそれぞ
れ溶融希釈塩中に少量ずつ分割して投入して互いに反応
させ、ナトリウム添加直前における希釈塩量を、希釈塩
内に投入されたフッ化タンタル酸カリウムの常に４０〜
１０００倍とすることが好ましい。Means for Solving the Problems The tantalum powder production method of the present invention comprises a high-temperature heat treatment step in which potassium fluoride tantalate is reduced by sodium and the resulting reduced tantalum powder is subjected to a high-temperature heat treatment in an inert atmosphere. The tantalum aggregate after the process is pulverized, magnesium is added thereto, and a low-temperature heat treatment step of performing low-temperature heat treatment under reduced pressure, and a high-temperature heat treatment Over 1000 ° C and 1250 ° C
At a temperature of less than 700 ° C. to 100 ° C.
It is carried out at a temperature of 0 ° C. In the above-mentioned production method, when potassium fluoride tantalate is reduced with sodium, potassium fluoride tantalate and sodium are each divided into small portions in a molten dilute salt and allowed to react with each other. The amount is always between 40 and 40 of the potassium fluorotantalate charged in the dilute salt.
Preferably it is 1000 times.
【０００８】本発明のタンタル粉末は、フッ化タンタル
酸カリウムをナトリウムで還元して得られた比表面積２
〜５ｍ2 ／ｇの還元タンタル粉末を不活性雰囲気下で高
温熱処理し、ついで金属マグネシウムを添加し、減圧下
で低温熱処理を行って得られたタンタル粉末であって、
このタンタル粉末を加圧成形して密度４．５〜５．０ｇ
／ｃｍ3 の成形体とし、この成形体を高温熱処理温度以
上の温度で真空焼結して、前記成形体の密度の１０３〜
１１５％の密度の焼結体とし、この焼結体をＥＩＡＪ
ＲＣ−２３６１に準拠して６０℃、１０Ｖで化成したも
のの比静電容量が８万〜２５万μＦＶ／ｇであることを
特徴とする。また、上記タンタル粉末は、真空焼結後の
焼結体の圧縮強度が真空焼結前の成形体の圧縮強度の３
〜２０倍となることが好ましい。また、本発明のタンタ
ル粉末は、フッ化タンタル酸カリウムをナトリウムで還
元して得られた比表面積２〜５ｍ2 ／ｇの還元タンタル
粉末を不活性雰囲気下で高温熱処理し、ついで金属マグ
ネシウムを添加し、減圧下で低温熱処理を行って得られ
たタンタル粉末であって、このタンタル粉末を加圧成形
して密度４．５〜５．０ｇ／ｃｍ3 の成形体とし、この
成形体を高温熱処理温度以上の温度で真空焼結して、前
記成形体の密度の１０３〜１１５％の密度の焼結体と
し、この焼結体をＥＩＡＪ ＲＣ−２３６１に準拠して
６０℃、１０Ｖで化成したものの比静電容量が６０℃、
１０Ｖで化成したものの比静電容量が８万〜２５万μＦ
Ｖ／ｇであり、かつ６０℃、２０Ｖで化成したものの比
静電容量が６０℃、１０Ｖで化成したものの比静電容量
の７０％以上であることを特徴とする。本発明のタンタ
ル電解コンデンサは、上記いずれかのタンタル粉末から
得られたことを特徴とする。[0008] The tantalum powder of the present invention has a specific surface area of 2 obtained by reducing potassium fluorotantalate with sodium.
５5 m 2 / g reduced tantalum powder is subjected to high-temperature heat treatment under an inert atmosphere, and then metal magnesium is added thereto, and the resulting tantalum powder is subjected to low-temperature heat treatment under reduced pressure,
This tantalum powder is molded under pressure to a density of 4.5 to 5.0 g.
/ Cm 3, and the formed body is vacuum-sintered at a temperature equal to or higher than the high-temperature heat treatment temperature, and has a density of 103 to
A sintered body having a density of 115% was obtained.
It is characterized by having a specific capacitance of 80,000 to 250,000 μFV / g, which is formed at 60 ° C. and 10 V according to RC-2361. In addition, the above-mentioned tantalum powder has a compression strength of the sintered body after vacuum sintering that is 3 times lower than that of the compact before vacuum sintering.
Preferably, it is up to 20 times. Further, the tantalum powder of the present invention is obtained by reducing potassium tantalate fluoride with sodium, and then subjecting the reduced tantalum powder having a specific surface area of 2 to 5 m 2 / g to a high-temperature heat treatment in an inert atmosphere, and then adding metallic magnesium. A tantalum powder obtained by performing a low-temperature heat treatment under reduced pressure to obtain a compact having a density of 4.5 to 5.0 g / cm 3 by press-molding the tantalum powder; Vacuum sintering at a temperature equal to or higher than the temperature to obtain a sintered body having a density of 103 to 115% of the density of the molded body, and the sintered body is formed at 60 ° C. and 10 V according to EIAJ RC-2361. The specific capacitance is 60 ° C,
The specific capacitance of those formed at 10V is 80,000 ~ 250,000μF
V / g, and the specific capacitance at 60 ° C. and 20 V is 70% or more of the specific capacitance at 60 ° C. and 10 V. The tantalum electrolytic capacitor of the present invention is characterized by being obtained from any of the above tantalum powders.
【０００９】[0009]
【発明の実施の形態】以下、本発明を詳細に説明する。
本発明のタンタル粉末の製法においては、まず、フッ化
タンタル酸カリウム（Ｋ2ＴａＦ7）を、溶融希釈塩中で
ナトリウムと反応させて還元し、還元タンタル粉末を得
る。溶融希釈塩としては、ＫＣｌ−ＫＦ系、ＫＣｌ−Ｎ
ａＣｌ系等の共晶塩が挙げられ、これらの塩を８００〜
９００℃に加熱して融液とし、この融液中に、フッ化タ
ンタル酸カリウムと還元剤であるナトリウムとを投入し
て、これらを反応させる。BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
In the method for producing a tantalum powder of the present invention, first, potassium fluorotantalate (K 2 TaF 7 ) is reduced by reacting with sodium in a molten dilute salt to obtain a reduced tantalum powder. KCl-KF, KCl-N
eutectic salts such as aCl-based salts;
The mixture is heated to 900 ° C. to form a melt, and potassium fluoride tantalate and sodium as a reducing agent are charged into the melt to react them.
【００１０】このようにナトリウムでフッ化タンタル酸
カリウムを還元する場合には、これらをそれぞれ連続的
に添加してもよいが、特に、フッ化タンタル酸カリウム
とナトリウムとをそれぞれ溶融希釈塩中に少量ずつ交互
に分割して投入し、互いに反応させることが好ましい。
さらには、ナトリウム添加直前における希釈塩量が、常
に希釈塩中のフッ化タンタル酸カリウムの４０〜１００
０倍であることが好ましい。In the case where potassium fluoride tantalate is reduced with sodium as described above, these may be added continuously, but particularly, potassium fluoride and sodium are separately added to the molten dilute salt. It is preferable that the components are alternately divided into small portions and then charged to react with each other.
Further, the amount of the diluted salt immediately before the addition of sodium is always 40 to 100% of the potassium fluoride tantalate in the diluted salt.
It is preferably 0 times.
【００１１】すなわち、まず、溶融希釈塩中にフッ化タ
ンタル酸カリウムを添加するが、この場合、希釈塩量
が、フッ化タンタル酸カリウムの４０〜１０００倍とな
るようにそれぞれの量を調節する。ついで、ナトリウム
を添加して、フッ化タンタル酸カリウムを還元する。そ
して、さらにフッ化タンタル酸カリウムを添加する。ま
た、この場合にも、希釈塩量が、フッ化タンタル酸カリ
ウムの４０〜１０００倍となるような量のフッ化タンタ
ル酸カリウムを添加する。このように、ナトリウム添加
直前における希釈塩量が、常にフッ化タンタル酸カリウ
ムの４０〜１０００倍であることが好ましい。That is, first, potassium fluoride tantalate is added to the molten dilute salt. In this case, the respective amounts are adjusted so that the amount of the dilute salt is 40 to 1000 times the potassium fluoride tantalate. . Then, sodium is added to reduce potassium fluorotantalate. Then, potassium fluoride tantalate is further added. Also in this case, potassium fluoride tantalate is added in such an amount that the amount of dilute salt is 40 to 1000 times the amount of potassium fluoride tantalate. As described above, it is preferable that the amount of the diluted salt immediately before the addition of sodium is always 40 to 1000 times the amount of potassium fluorotantalate.
【００１２】フッ化タンタル酸カリウムとナトリウムと
の反応終了後、希釈塩を冷却し、得られた集塊を水、弱
酸性水溶液等で繰り返し洗浄して、希釈塩を除去し、還
元タンタル粉末を得る。この場合、必要に応じて、遠心
分離、濾過等の分離操作を組み合わせたり、フッ酸と過
酸化水素が溶解している溶液等で粒子を洗浄、精製した
りしてもよい。After completion of the reaction between potassium fluoride and sodium tantalate, the diluted salt is cooled, and the obtained agglomerate is repeatedly washed with water, a weakly acidic aqueous solution or the like to remove the diluted salt, and to reduce the reduced tantalum powder. obtain. In this case, if necessary, separation operations such as centrifugation and filtration may be combined, or the particles may be washed and purified with a solution in which hydrofluoric acid and hydrogen peroxide are dissolved.
【００１３】このようにフッ化タンタル酸カリウムの量
と希釈塩の量とを調節しながらフッ化タンタル酸カリウ
ムを還元し、還元タンタル粉末を生成させると、得られ
る粉末が細かくなり、高ＣＶを達成できるタンタル粉末
となる。希釈塩量が、フッ化タンタル酸カリウムの４０
倍未満では、原料であるフッ化タンタル酸カリウムの希
釈塩中での濃度が高すぎて還元反応速度が速くなり、生
成するタンタル粒子の粒径が大きくなりすぎる場合があ
る。一方、希釈塩の量が１０００倍を超えると還元反応
速度が低下し、生産性が低下する。こうして得られた還
元タンタル粉末のＢＥＴ法による比表面積は、通常、２
〜５ｍ2 ／ｇである。As described above, when potassium fluoride tantalate is reduced while adjusting the amount of potassium fluoride tantalate and the amount of diluting salt to produce reduced tantalum powder, the obtained powder becomes finer and high CV is obtained. Achievable tantalum powder. The amount of the diluted salt is 40% of potassium fluorotantalate.
If the ratio is less than twice, the concentration of the starting material potassium fluoride tantalate in the dilute salt is too high, so that the reduction reaction speed is increased, and the particle size of the generated tantalum particles may be too large. On the other hand, when the amount of the dilute salt exceeds 1000 times, the reduction reaction rate decreases, and the productivity decreases. The specific surface area of the reduced tantalum powder thus obtained by the BET method is usually 2
５5 m 2 / g.
【００１４】なお、還元反応時には、溶融希釈塩中に酸
化ホウ素（Ｂ2Ｏ3）やフッ化ホウ素カリウム（ＫＢ
Ｆ4）などのホウ素化合物を添加してもよい。ホウ素化
合物を添加することによって、還元タンタル粉末の過度
な微細化を抑制することができる。ここでのホウ素の添
加量は、タンタル粉末に対して５〜１００ｐｐｍが好ま
しい。５ｐｐｍ未満では、微細化抑制効果が不十分であ
り、一方１００ｐｐｍを超えると、焼結時にホウ素酸化
物の気相を介しての移動が増加し、コンデンサとした時
にリード線上に析出する場合があり好ましくない。During the reduction reaction, boron oxide (B 2 O 3 ) or potassium boron fluoride (KB)
A boron compound such as F 4 ) may be added. By adding the boron compound, excessive reduction in the size of the reduced tantalum powder can be suppressed. Here, the addition amount of boron is preferably 5 to 100 ppm based on the tantalum powder. If it is less than 5 ppm, the effect of suppressing fineness is insufficient, while if it exceeds 100 ppm, the movement of the boron oxide through the gas phase during sintering increases, and it may precipitate on the lead wire when it is used as a capacitor. Not preferred.
【００１５】得られた還元タンタル粉末を、ついで、不
活性雰囲気下で高温熱処理して熱凝集させ、タンタル凝
集体とする高温熱処理工程を行う。ここで不活性雰囲気
とは、ヘリウム、アルゴンなどの不活性ガス雰囲気の
他、減圧雰囲気（１０-3〜１０ -4ｔｏｒｒ）を含む。こ
の高温熱処理工程では、還元タンタル粉末を、１０００
℃以上、１２５０℃未満の温度で熱処理することが重要
である。このような温度で熱処理することによって、タ
ンタル粉末中に存在する極微細な粒子を比較的粒径の大
きな２次粒子とすることができる。１０００℃未満で
は、十分に還元タンタル粉末を熱凝集させることができ
ない。一方１２５０℃を超えると、熱凝集後の粉末が固
くなりすぎて解砕できなくなるとともに、得られるタン
タル粉末の表面積が小さくなり、高ＣＶを達成できない
粉末となる。比較的大きな２次粒子を成形、焼結して得
られた焼結体は、極微細な粒子から得られた焼結体より
も大きな空孔を有するため、これを陽極電極として使用
する場合に、電解質溶液が焼結体の内部まで浸透し、高
容量化をはかることができる。そして、詳しくは後述す
るが、ここでの高温熱処理温度を１０００℃以上、１２
５０℃未満とし、さらに、タンタル焼結体製造時の焼結
温度を１０００℃〜１４５０℃、好ましくは１１５０〜
１４００℃とすることによって、十分な強度を有し、か
つ、適度な空孔も備えたタンタル焼結体を製造できる。
高温熱処理工程における加熱時間は、通常１５分〜２時
間程度である。The obtained reduced tantalum powder is then
High temperature heat treatment in an active atmosphere to cause thermal aggregation and tantalum coagulation
A high-temperature heat treatment step of forming a mass is performed. Where the inert atmosphere
Is an atmosphere of an inert gas such as helium or argon.
Other, reduced pressure atmosphere (10-3-10 -Fourtorr). This
In the high temperature heat treatment step, the reduced tantalum powder is
It is important to heat-treat at a temperature of 1250C or higher and lower than 1250C
It is. Heat treatment at such a temperature allows the
Ultra-fine particles present in iron powder
Secondary particles. Below 1000 ° C
Can sufficiently coagulate the reduced tantalum powder
Absent. On the other hand, when the temperature exceeds 1250 ° C., the powder after thermal aggregation is hardened.
It becomes too crushed to become too crushed and the resulting tan
The surface area of the tall powder is small and high CV cannot be achieved
It becomes a powder. Forming and sintering relatively large secondary particles
The sintered body obtained from the sintered body obtained from ultra-fine particles
Also have large pores, which are used as anode electrodes
The electrolyte solution penetrates into the sintered body,
The capacity can be increased. The details will be described later.
However, the high-temperature heat treatment temperature here is 1000 ° C. or more and 12
Sintering at the time of manufacturing a tantalum sintered body at less than 50 ° C
The temperature is from 1000 ° C. to 1450 ° C., preferably 1150 ° C.
By setting the temperature to 1400 ° C., sufficient strength is obtained.
In addition, a tantalum sintered body having appropriate holes can be manufactured.
The heating time in the high-temperature heat treatment step is usually 15 minutes to 2:00
It is about between.
【００１６】なお、この高温熱処理工程の前には、遠心
機などを使用して、タンタル粉末に振動を与えながら、
粉体全体が均一に濡れる量の水を添加する予備凝集工程
を行ってもよい。この予備凝集工程を行うことによっ
て、より強固な凝集体を得ることができる。また予備凝
集工程で添加する水に、金属に対して２０〜４００ｐｐ
ｍのリン、または、５〜１００ｐｐｍホウ素等をあらか
じめ添加しておくことによって、一次粒子の融合成長を
抑え、高表面積を維持しながら熱凝集させることができ
る。ここで加えるリンの形態としては、リン酸、六フッ
化リンアンモニウム等が挙げられる。ホウ素の形態とし
ては、酸化ホウ素（Ｂ2Ｏ3）やフッ化ホウ素カリウム
（ＫＢＦ4）などのホウ素化合物が挙げられる。なお、
リンについては、後述する加圧成形の前であれば、いつ
添加してもかまわない。加圧成形前に添加することによ
って、ついで行われる焼結が過度に進行することを抑制
できる。Prior to this high-temperature heat treatment step, the tantalum powder is vibrated using a centrifuge or the like.
A preliminary coagulation step of adding water in such an amount that the entire powder is uniformly wetted may be performed. By performing this preliminary aggregation step, a stronger aggregate can be obtained. In addition, the water added in the pre-coagulation step has a metal content of 20 to 400 pp.
By adding phosphorus of m or 5 to 100 ppm of boron in advance, fusion growth of primary particles can be suppressed and thermal aggregation can be performed while maintaining a high surface area. Examples of the form of phosphorus to be added here include phosphoric acid and ammonium phosphate hexafluoride. Examples of the form of boron include boron compounds such as boron oxide (B 2 O 3 ) and potassium boron fluoride (KBF 4 ). In addition,
Phosphorus may be added at any time before pressure molding described below. By adding before pressure molding, excessive progress of sintering to be performed subsequently can be suppressed.
【００１７】高温熱処理工程で得られたケーキ状のタン
タル粉末を、大気中または不活性ガス中で解砕した後、
これにマグネシウムを添加し、減圧下で加熱して、タン
タル粒子中の酸素とマグネシウムを反応させ脱酸素する
低温熱処理工程を行う。この低温熱処理工程では、マグ
ネシウムが添加されたタンタル粉末を、７００〜１００
０℃未満の温度で、通常２〜１０時間程度熱処理する。
このような条件で熱処理することによって、タンタル粉
末内部の酸素は拡散して表面まで移動し、マグネシウム
と反応して酸化マグネシウムを生成し、酸素の大部分が
酸化マグネシウムとして除去される。特に温度は、マグ
ネシウムチップが溶融し、タンタルの酸化被膜が拡散し
始める７００℃以上とし、高温熱処理の領域に至り、表
面拡散による表面積の減少が激しくなる１０００℃以下
とする。After the cake-like tantalum powder obtained in the high-temperature heat treatment step is crushed in the air or in an inert gas,
Magnesium is added thereto, and the mixture is heated under reduced pressure to perform a low-temperature heat treatment step of reacting oxygen and magnesium in the tantalum particles to remove oxygen. In this low temperature heat treatment step, the tantalum powder to which magnesium is added is
Heat treatment is usually performed at a temperature lower than 0 ° C. for about 2 to 10 hours.
By performing the heat treatment under such conditions, oxygen in the tantalum powder diffuses and moves to the surface, reacts with magnesium to generate magnesium oxide, and most of the oxygen is removed as magnesium oxide. In particular, the temperature is set to 700 ° C. or higher, at which the magnesium chip is melted and the oxide film of tantalum begins to diffuse, and reaches 1000 ° C. or lower, which reaches a high-temperature heat treatment region and in which the surface area is greatly reduced by surface diffusion.
【００１８】ついで、低温熱処理工程で脱酸素されたタ
ンタル粉末に対して、徐々に空気を導入して、タンタル
粒子の表面に安定な被膜を形成する徐酸化処理を行う。
その後、これを酸性溶液で洗浄する酸洗工程を行って、
残留しているマグネシムやマグネシウム由来の酸化マグ
ネシウム等の物質を除去し、乾燥する。Next, air is gradually introduced into the tantalum powder deoxygenated in the low-temperature heat treatment step to perform a gradual oxidation treatment for forming a stable film on the surface of the tantalum particles.
After that, perform an acid washing step of washing this with an acidic solution,
The remaining substances such as magnesium oxide and magnesium oxide derived from magnesium are removed and dried.
【００１９】このようにして得られたタンタル粉末を用
いて、タンタル電解コンデンサを製造する場合には、ま
ず、バインダーとして１〜５重量％程度のショウノウ
（Ｃ10Ｈ16Ｏ）等を加えて加圧成形し、密度４．５〜
５．０ｇ／ｃｍ3 の成形体を製造する。ついで、このタ
ンタル成形体を１０-4〜１０-6ｔｏｒｒ程度の真空条件
下において、高温熱処理工程での加熱温度以上の温度、
好ましくは、高温熱処理工程の加熱温度よりも０〜２０
０℃高い温度、すなわち１０００〜１４５０℃程度で、
０．３〜１時間程度加熱して焼結し、焼結体を製造す
る。より好ましくは、１１５０〜１４００℃である。こ
のように、高温熱処理工程の加熱温度よりも０〜２００
℃高い温度で焼結すると、十分な強度を有し、かつ、適
度な空孔も備えたタンタル焼結体を製造できる。When a tantalum electrolytic capacitor is manufactured using the tantalum powder thus obtained, first, about 1 to 5% by weight of camphor (C 10 H 16 O) or the like is added as a binder. Pressed, density 4.5-
A molded body of 5.0 g / cm 3 is produced. Next, the tantalum compact is heated under a vacuum condition of about 10 −4 to 10 −6 torr at a temperature equal to or higher than the heating temperature in the high-temperature heat treatment step.
Preferably, the heating temperature is higher than the heating temperature of the high temperature heat treatment step by 0 to 20.
At 0 ° C. higher temperature, that is, about 1000 to 1450 ° C.,
It is sintered for about 0.3 to 1 hour to produce a sintered body. More preferably, it is 1150-1400 degreeC. As described above, the heating temperature of the high temperature heat treatment step is 0 to 200
By sintering at a high temperature, it is possible to produce a tantalum sintered body having sufficient strength and also having appropriate holes.
【００２０】また、ここでは、焼結体の密度が成形体の
密度の１０３〜１１５％となることが好ましい。１０３
％未満では、強度が不十分であり、実用的ではない。一
方、１１５％を超えると、焼結による体積収縮が大きす
ぎて、焼結体の寸法を制御しにくい。焼結体の密度を成
形体の密度の１０３〜１１５％とすることによって、タ
ンタル電解コンデンサへの使用に適した焼結体となる。Here, the density of the sintered body is preferably 103 to 115% of the density of the molded body. 103
%, The strength is insufficient and is not practical. On the other hand, if it exceeds 115%, the volume shrinkage due to sintering is too large, and it is difficult to control the dimensions of the sintered body. By setting the density of the sintered body to 103 to 115% of the density of the molded body, the sintered body suitable for use in a tantalum electrolytic capacitor can be obtained.
【００２１】さらに、焼結体の圧縮強度が成形体の圧縮
強度の３〜２０倍となることが好ましい。３倍未満で
は、強度が不十分であり、実用的ではなく、タンタル電
解コンデンサとした場合に異常が起こる場合がある。一
方、２０倍を超えると、強度が大きすぎるとともに固す
ぎて、空孔も少ない。そのため、酸化マンガンの含浸が
不十分となり、陰極体の製造が困難となる場合がある。Further, the compression strength of the sintered body is preferably 3 to 20 times the compression strength of the molded body. If it is less than three times, the strength is insufficient and it is not practical, and when a tantalum electrolytic capacitor is used, an abnormality may occur. On the other hand, when it exceeds 20 times, the strength is too high and too hard, and the number of pores is small. Therefore, impregnation with manganese oxide becomes insufficient, and it may be difficult to produce a cathode body.
【００２２】このようにして得られた焼結体を、ＥＩＡ
Ｊ ＲＣ−２３６１に準拠して、６０℃、１０Ｖで化成
することによって、この焼結体を陽極電極として使用し
たタンタル電解コンデンサは、比静伝容量が８万〜２５
万μＦＶ／ｇの高容量となる。なお、ＥＩＡＪ ＲＣ−
２３６１は、日本電子機械工業会規格において電解コン
デンサ用タンタル焼結素子の試験方法として定められて
いるものである。また、この焼結体を６０℃、２０Ｖで
化成した場合の比静電容量は、６０℃、１０Ｖで化成し
たものの比静電容量の７０％以上であることが好まし
い。この値が７０％未満であると、陽極電極への使用に
適した適度な大きさの空孔が少なすぎて、陰極形成用の
二酸化マンガンを形成しにくく、また、電解質の含浸も
不十分となる場合がある。また、焼結体を構成している
一次粒子サイズにばらつきがあって、２０Ｖで化成した
場合に化成被膜の厚さが不十分となる微粒子が多いと、
ＣＶ低下のみならず不完全な化成被膜形成により漏れ電
流が増加してしまう場合もある。The sintered body obtained in this way is
According to JRC-2361, a tantalum electrolytic capacitor using this sintered body as an anode electrode by forming at 60 ° C. and 10 V has a specific static transfer capacity of 80,000 to 25.
The capacity is as high as 10,000 μFV / g. In addition, EIAJ RC-
2361 is defined as a test method for a tantalum sintered element for an electrolytic capacitor in the standards of the Japan Electronic Machinery Manufacturers Association. The specific capacitance when this sintered body is formed at 60 ° C. and 20 V is preferably 70% or more of the specific capacitance of the product formed at 60 ° C. and 10 V. If this value is less than 70%, there are too few pores of a suitable size suitable for use in the anode electrode, it is difficult to form manganese dioxide for forming the cathode, and impregnation of the electrolyte is insufficient. May be. In addition, there is a variation in the primary particle size constituting the sintered body, and when there are many fine particles whose chemical conversion coating thickness is insufficient when converted at 20 V,
Leakage current may increase due to incomplete conversion film formation as well as CV reduction.
【００２３】なお、この焼結体を陽極電極として使用す
る場合には、還元タンタル粉末をプレス成形する前に、
この粉末中にリード線を埋め込んでプレス成形し、焼結
して、リード線を一体化させる。そして、これを化成し
て陽極電極とする。化成条件としては、例えば温度３０
〜９０℃、濃度０．１重量％程度のリン酸、硝酸等の電
解溶液中で、３０〜１２０ｍＡ／ｇの電流密度で２０〜
６０Ｖまで昇圧して１〜３時間処理する条件を例示でき
る。具体的には、さらに、公知の方法で二酸化マンガ
ン、酸化鉛や導電性高分子等の固体電解質層、グラファ
イト層、銀ペースト層を焼結体上に順次形成し、ついで
その上に陰極端子をハンダ付けなどで接続した後、樹脂
外被を形成して、固体電解コンデンサー用の陽極電極と
して使用する。When this sintered body is used as an anode, before the reduced tantalum powder is pressed,
The lead wire is embedded in the powder, pressed, sintered, and integrated. This is formed into an anode electrode. As the formation conditions, for example, a temperature of 30
At a current density of 30 to 120 mA / g in an electrolytic solution of phosphoric acid, nitric acid,
Conditions for boosting to 60V and treating for 1 to 3 hours can be exemplified. Specifically, manganese dioxide, a solid electrolyte layer such as lead oxide or a conductive polymer, a graphite layer, and a silver paste layer are sequentially formed on the sintered body by a known method, and then a cathode terminal is formed thereon. After connection by soldering or the like, a resin jacket is formed and used as an anode electrode for a solid electrolytic capacitor.
【００２４】このようなタンタル粉末にあっては、還元
タンタル粉末に対して高温熱処理工程を１０００℃以
上、１２５０℃未満の温度で行い、低温熱処理工程を７
００℃〜１０００℃の温度で行うことによって得られる
ので、表面積が大きく微細な還元タンタル粉末であり、
かつ、過度に凝集しておらず、表面積も２〜５ｍ2 ／ｇ
程度と高表面積である。よって、タンタル電解コンデン
サの陽極電極への使用に適している。また、還元タンタ
ル粉末を製造する場合に、フッ化タンタル酸カリウムと
ナトリウムとをそれぞれ溶融希釈塩中に少量ずつ分割し
て投入して互いに反応させ、ナトリウム添加直前におけ
る希釈塩量を常にフッ化タンタル酸カリウムの４０〜１
０００倍とすることによって、タンタル電解コンデンサ
の陽極電極への使用に適した、より細かい還元タンタル
粉末が得られる。In such a tantalum powder, the reduced tantalum powder is subjected to a high-temperature heat treatment at a temperature of 1000 ° C. or more and less than 1250 ° C.
Since it is obtained by performing at a temperature of 00C to 1000C, it is a fine reduced tantalum powder having a large surface area,
And it is not excessively aggregated and has a surface area of 2 to 5 m 2 / g.
Degree and high surface area. Therefore, it is suitable for use as an anode electrode of a tantalum electrolytic capacitor. In the case of producing reduced tantalum powder, potassium and sodium fluoride tantalate are each divided into small portions in a molten dilute salt, and are charged and allowed to react with each other. 40-1 of potassium acid
By setting the ratio to 000, a finer reduced tantalum powder suitable for use as the anode electrode of a tantalum electrolytic capacitor can be obtained.
【００２５】また、このようなタンタル粉末を加圧成形
し、さらに真空焼結して焼結体とする際には、成形体の
密度を４．５〜５．１ｇ／ｃｍ3 とし、かつ、焼結体の
密度を成形体の密度の１０３〜１１５％とすることによ
って、強度が優れていて、寸法制御もしやすい焼結体と
なり、タンタル電解コンデンサへの使用に適した焼結体
となる。さらに、焼結体の圧縮強度を、真空焼結前の成
形体の強度の３〜２０倍とすることにより、より実用的
なものとなる。このような焼結体を使用することによっ
て、これをＥＩＡＪ ＲＣ−２３６１に準拠して、６０
℃、１０Ｖで化成した場合の比静伝容量が８万〜２５万
μＦＶ／ｇの高容量となり、さらには、この焼結体を６
０℃、２０Ｖで化成した場合の比静電容量は、６０℃、
１０Ｖで化成したものの比静電容量の７０％以上とな
り、陽極電極への使用に適した適度な大きさの空孔を適
度に有するものとなる。When such a tantalum powder is subjected to pressure molding and further vacuum sintering to form a sintered body, the density of the compact is 4.5 to 5.1 g / cm 3 , and By setting the density of the sintered body to 103 to 115% of the density of the molded body, the sintered body has excellent strength and is easy to control the size, and is a sintered body suitable for use in a tantalum electrolytic capacitor. Further, by setting the compressive strength of the sintered body to 3 to 20 times the strength of the molded body before vacuum sintering, it becomes more practical. By using such a sintered body, it can be converted to 60 according to EIAJ RC-2361.
The specific static transfer capacity when formed at 10 ° C. and 10 V is as high as 80,000 to 250,000 μFV / g.
The specific capacitance when formed at 0 ° C. and 20 V is 60 ° C.
It becomes 70% or more of the specific capacitance of the material formed at 10 V, and has an appropriate size of pores suitable for use as an anode electrode.
【００２６】[0026]
【実施例】以下、本発明を実施例を挙げて具体的に説明
する。 ［実施例１］蓋、かきまぜ棒、ナトリウム投入口、原料
投入口、アルゴンガス投入口および排気口を備えたニッ
ケル製の反応器に、希釈塩として、フッ化カリウムと塩
化カリウムの混合物を２００ｋｇ入れ、８３０℃まで昇
温して溶融した。ついで、フッ化タンタル酸カリウムと
ナトリウムを交互に、小分けしてこの反応器に投入し
た。この際、ナトリウムの添加直前においては、希釈塩
量がフッ化タンタル酸カリウムの８０〜１２０倍となる
ようにした。なお、フッ化タンタル酸カリウムの全投入
量は４０ｋｇで、ナトリウムの全投入量は１２ｋｇであ
った。還元反応終了後冷却し、得られた集塊を砕き、弱
酸性水溶液で洗浄し、還元タンタル粒末を得た。さら
に、フッ酸と過酸化水素を含む洗浄液で精製処理した。
このようにして得られたタンタル粒子のＢＥＴ法による
表面積および元素分析結果を表１に示す。EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples. [Example 1] 200 kg of a mixture of potassium fluoride and potassium chloride as a diluting salt was placed in a nickel reactor equipped with a lid, a stirring rod, a sodium inlet, a raw material inlet, an argon gas inlet, and an outlet. The temperature was raised to 830 ° C. to melt. Next, potassium and sodium fluoride tantalate were alternately and subdivided and charged into the reactor. At this time, immediately before the addition of sodium, the amount of the diluted salt was adjusted to be 80 to 120 times the amount of potassium fluorotantalate. The total amount of potassium fluoride tantalate was 40 kg, and the total amount of sodium was 12 kg. After the completion of the reduction reaction, the mixture was cooled, and the obtained agglomerates were crushed and washed with a weakly acidic aqueous solution to obtain reduced tantalum particles. Further, purification was performed using a cleaning solution containing hydrofluoric acid and hydrogen peroxide.
Table 1 shows the surface area and the elemental analysis results of the tantalum particles thus obtained by the BET method.
【００２７】次に、還元タンタル粉末に対してリンが１
５０ｐｐｍになるようにリン酸を添加した後、これをボ
ールに入れて水を満たした。そして、これを遠心脱水器
のポット中に濾紙を装着して投入した。所定時間脱水
後、水分を測定したところ５ｗｔ％であった。脱水後の
タンタル粉をトレイに広げて放置して、これを自然乾燥
した（予備凝集）。そして、これを加熱炉に入れて減圧
下（１０-4ｔｏｒｒ）、１２００℃で０．５時間加熱し
て、高温熱処理工程を行い、熱凝集させた。そして、熱
凝集させた団塊を解砕して、目開き２５０μｍのふるい
を通過させた。粉砕物（タンタル）に対して５重量％の
マグネシウムチップを添加して、減圧下、８００℃で４
時間保持し、低温熱処理工程を行ってタンタル中の酸素
とマグネシウムを反応させる脱酸素を行った。そして、
その後の冷却過程でアルゴンガス中に空気を導入しタン
タル粉末の徐酸化安定処理を行い、炉から取り出した。
ついで、取り出した粉末を硝酸水で洗浄し、マグネシウ
ムと酸化マグネシウムを洗浄し、除去した。得られたタ
ンタル粉末の物性分析および元素分析をしたところ、表
２のとおりであった。Next, phosphorus is added to the reduced tantalum powder in an amount of 1%.
After adding phosphoric acid to 50 ppm, this was put in a bowl and filled with water. Then, this was put into the pot of the centrifugal dehydrator with the filter paper attached. After dehydration for a predetermined time, the water content was measured and found to be 5 wt%. The dehydrated tantalum powder was spread on a tray and allowed to stand, and was naturally dried (preliminary aggregation). Then, this was placed in a heating furnace and heated at 1200 ° C. for 0.5 hour under reduced pressure (10 −4 torr) to perform a high-temperature heat treatment step to cause thermal aggregation. Then, the aggregate that had been thermally agglomerated was crushed and passed through a sieve having openings of 250 μm. 5% by weight of magnesium chips is added to the pulverized material (tantalum).
After holding for a long time, a low-temperature heat treatment step was performed to perform deoxidation in which oxygen in the tantalum reacted with magnesium. And
In the subsequent cooling process, air was introduced into the argon gas to perform a slow oxidation stabilization treatment on the tantalum powder, and the powder was taken out of the furnace.
Next, the powder thus taken out was washed with a nitric acid solution, and magnesium and magnesium oxide were washed and removed. Physical properties and elemental analysis of the obtained tantalum powder were as shown in Table 2.
【００２８】この粉末を加圧成形して密度を４．５ｇ／
ｃｍ3 の成形体とし、これを１３００℃、２０分間真空
焼結（１０-5ｔｏｒｒ）して焼結体を製造した。成形体
および焼結体について、成形体密度、成形体強度（圧縮
強度）、焼結体密度、焼結体強度（圧縮強度）を測定し
た。結果を表３に示す。This powder was molded under pressure to a density of 4.5 g /
A molded body having a size of 3 cm 3 was vacuum-sintered (10 −5 torr) at 1300 ° C. for 20 minutes to produce a sintered body. With respect to the molded body and the sintered body, the molded body density, the molded body strength (compression strength), the sintered body density, and the sintered body strength (compression strength) were measured. Table 3 shows the results.
【００２９】さらに得られた焼結体を６０℃の１％リン
酸水溶液中にて化成電圧１０Ｖで化成した後、２５℃、
３０％の硫酸水溶液中でＣＶ測定を行った。また、同様
にして、化成電圧２０Ｖで化成した後、ＣＶ測定を行っ
た。なお、化成電流密度は９０ｍＡ／ｇとした。これら
の結果も表４に示す。Further, the obtained sintered body was formed in a 1% phosphoric acid aqueous solution at 60 ° C. at a formation voltage of 10 V, and then formed at 25 ° C.
CV measurement was performed in a 30% aqueous sulfuric acid solution. Similarly, after forming at a formation voltage of 20 V, CV measurement was performed. The formation current density was 90 mA / g. Table 4 also shows these results.
【００３０】［実施例２］実施例１と同様の反応器を用
いて、希釈塩としてフッ化カリウムと塩化カリウムの混
合物を４００ｋｇ入れ、微細化剤としてＫＢＦ4 を２０
ｇ添加し、８３０℃まで昇温して溶融した。ついで、フ
ッ化タンタル酸カリウムとナトリウムを交互に、小分け
にしてこの反応容器に投入した。この際、ナトリウムの
添加直前においては、希釈塩量が常にフッ化タンタル酸
カリウムの２００〜４００倍となるようにした。なお、
フッ化タンタル酸カリウムの全投入量は４０ｋｇで、ナ
トリウムの全投入量は１２ｋｇであった。還元反応終了
後冷却し、得られた集塊を砕き、弱酸性水溶液で洗浄
し、還元タンタル粒末を得た。さらに、フッ酸と過酸化
水素を含む洗浄液で精製処理した。このようにして得ら
れたタンタル粒子のＢＥＴ法による表面積および元素分
析結果を表１に示す。Example 2 Using the same reactor as in Example 1, 400 kg of a mixture of potassium fluoride and potassium chloride was added as a diluting salt, and KBF 4 was added as a refining agent in an amount of 20 kg.
g was added and the temperature was raised to 830 ° C. to melt. Then, potassium fluoride and sodium fluoride tantalate were alternately divided into small portions and charged into the reaction vessel. At this time, immediately before the addition of sodium, the amount of the diluted salt was always 200 to 400 times the amount of potassium fluorotantalate. In addition,
The total charge of potassium fluorotantalate was 40 kg and the total charge of sodium was 12 kg. After the completion of the reduction reaction, the mixture was cooled, and the obtained agglomerates were crushed and washed with a weakly acidic aqueous solution to obtain reduced tantalum particles. Further, purification was performed using a cleaning solution containing hydrofluoric acid and hydrogen peroxide. Table 1 shows the surface area and the elemental analysis results of the tantalum particles thus obtained by the BET method.
【００３１】次に、還元タンタル粉末に対してリンが３
００ｐｐｍになるようにリン酸を添加した後、これをボ
ールに入れて水を満たした。そして、これを遠心脱水器
のポット中に濾紙を装着して投入した。所定時間脱水
後、水分を測定したところ５ｗｔ％であった。脱水後の
タンタル粉をトレイに広げて放置して、これを自然乾燥
した（予備凝集）。そして、これを加熱炉に入れて減圧
下（１０-4ｔｏｒｒ）、１２００℃で０．５時間加熱し
て、高温熱処理工程を行い、熱凝集させた。そして、熱
凝集させた団塊を解砕して、目開き２５０μｍのふるい
を通過させた。粉砕物（タンタル）に対して５重量％の
マグネシウムチップを添加して、減圧下、８００℃で４
時間保持し、低温熱処理工程を行ってタンタル中の酸素
とマグネシウムを反応させる脱酸素を行った。そして、
その後の冷却過程でアルゴンガス中に空気を導入しタン
タル粉末の徐酸化安定処理を行い、炉から取り出した。
ついで、取り出した粉末を硝酸水で洗浄し、マグネシウ
ムと酸化マグネシウムを洗浄し、除去した。得られたタ
ンタル粉末の物性分析および元素分析をしたところ、表
２のとおりであった。Next, phosphorus is added to the reduced tantalum powder by 3%.
After adding phosphoric acid so as to be 00 ppm, this was put in a ball and filled with water. Then, this was put into the pot of the centrifugal dehydrator with the filter paper attached. After dehydration for a predetermined time, the water content was measured and found to be 5 wt%. The dehydrated tantalum powder was spread on a tray and allowed to stand, and was naturally dried (preliminary aggregation). Then, this was placed in a heating furnace and heated at 1200 ° C. for 0.5 hour under reduced pressure (10 −4 torr) to perform a high-temperature heat treatment step to cause thermal aggregation. Then, the aggregate that had been thermally agglomerated was crushed and passed through a sieve having openings of 250 μm. 5% by weight of magnesium chips is added to the pulverized material (tantalum).
After holding for a long time, a low-temperature heat treatment step was performed to perform deoxidation in which oxygen in the tantalum reacted with magnesium. And
In the subsequent cooling process, air was introduced into the argon gas to perform a slow oxidation stabilization treatment on the tantalum powder, and the powder was taken out of the furnace.
Next, the powder thus taken out was washed with a nitric acid solution, and magnesium and magnesium oxide were washed and removed. Physical properties and elemental analysis of the obtained tantalum powder were as shown in Table 2.
【００３２】この粉末を加圧成形して密度を４．５ｇ／
ｃｍ3 の成形体とし、これを１３００℃、２０分間真空
焼結（１０-5ｔｏｒｒ）して焼結体を製造した。成形体
および焼結体について、成形体密度、成形体強度（圧縮
強度）、焼結体密度、焼結体強度（圧縮強度）を測定し
た。結果を表３に示す。This powder was molded under pressure to a density of 4.5 g /
A molded body having a size of 3 cm 3 was vacuum-sintered (10 −5 torr) at 1300 ° C. for 20 minutes to produce a sintered body. With respect to the molded body and the sintered body, the molded body density, the molded body strength (compression strength), the sintered body density, and the sintered body strength (compression strength) were measured. Table 3 shows the results.
【００３３】さらに得られた焼結体を６０℃の１％リン
酸水溶液中にて化成電圧１０Ｖで化成した後、２５℃、
３０％の硫酸水溶液中でＣＶ測定を行った。また、同様
にして、化成電圧２０Ｖで化成した後、ＣＶ測定を行っ
た。なお、化成電流密度は９０ｍＡ／ｇとした。これら
の結果も表４に示す。Further, the obtained sintered body was formed in a 1% phosphoric acid aqueous solution at 60 ° C. at a formation voltage of 10 V.
CV measurement was performed in a 30% aqueous sulfuric acid solution. Similarly, after forming at a formation voltage of 20 V, CV measurement was performed. The formation current density was 90 mA / g. Table 4 also shows these results.
【００３４】なお、実施例１〜２において成形体および
焼結体の強度は、１５０ｍｇのタンタル粉末を直径３ｍ
ｍのペレットに成形したものを用い、その直径方向に荷
重を加えていき、ペレットに亀裂が生じた際の荷重を、
強度として表した。In Examples 1 and 2, the strength of the compact and sintered compact was 150 mg of tantalum powder having a diameter of 3 m.
m using a pellet formed into a pellet, and applying a load in the diameter direction of the pellet, the load when a crack occurs in the pellet,
Expressed as strength.
【００３５】[0035]
【表１】 [Table 1]
【００３６】[0036]
【表２】 [Table 2]
【００３７】[0037]
【表３】 [Table 3]
【００３８】[0038]
【表４】 [Table 4]
【００３９】以上、表１〜４に示したように、本実施例
で得られたタンタル粉末により、タンタル電解コンデン
サに使用するのに最適な強度を有し、高ＣＶ（８万〜２
５万μＦＶ／ｇ）を達成するペレットを作成することが
できた。また、本実施例のタンタル粉末を使用すると、
成形体密度に対する焼結体密度は１０３〜１１５％の範
囲内であり、また、成形体強度に対する焼結体密度は３
〜２０倍であり、さらに、１０ＶでのＣＶ値に対する２
０ＶのＣＶ値は７０％以上であった。As described above, as shown in Tables 1 to 4, the tantalum powder obtained in the present embodiment has the optimum strength for use in a tantalum electrolytic capacitor and has a high CV (80,000 to 2
It was possible to produce a pellet achieving 50,000 μFV / g). Further, when the tantalum powder of the present embodiment is used,
The density of the sintered body with respect to the density of the compact is in the range of 103 to 115%, and the density of the sintered body with respect to the strength of the compact is 3%.
２０20 times, and 2 times the CV value at 10V.
The CV value at 0 V was 70% or more.
【００４０】[0040]
【発明の効果】以上説明したように本発明のタンタル粉
末は、還元タンタル粉末に対して高温熱処理工程を１０
００℃以上、１２５０℃未満の温度で行い、低温熱処理
工程を７００℃〜１０００℃の温度で行うことによって
得られるので、表面積が大きく微細な還元タンタル粉末
であり、かつ、過度に凝集しておらず、表面積も２〜５
ｍ2 ／ｇ程度と高表面積である。よって、ＣＶが８万〜
２５万μＦＶ／ｇのタンタル電解コンデンサを製造でき
る。また、本発明の製法によれば、ＣＶが８万〜２５万
μＦＶ／ｇ以上の高ＣＶを達成可能なタンタル粉末が得
られる。As described above, the tantalum powder of the present invention is obtained by subjecting reduced tantalum powder to a high temperature heat treatment step.
Since it is obtained by performing the low-temperature heat treatment step at a temperature of 700 ° C. to 1000 ° C. at a temperature of at least 00 ° C. and less than 1250 ° C., it is a fine reduced tantalum powder having a large surface area and excessively agglomerated. And surface area 2-5
The surface area is as high as about m 2 / g. Therefore, CV is 80,000 ~
A 250,000 μFV / g tantalum electrolytic capacitor can be manufactured. Further, according to the production method of the present invention, a tantalum powder capable of achieving a high CV of 80 to 250,000 μFV / g or more can be obtained.
───────────────────────────────────────────────────── フロントページの続き Ｆターム(参考） 4K017 AA01 BA07 DA08 EH01 4K018 BC01 DA32 KA39 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4K017 AA01 BA07 DA08 EH01 4K018 BC01 DA32 KA39
Claims (7)
還元し、得られた還元タンタル粉末を不活性雰囲気下で
高温熱処理する高温熱処理工程と、高温熱処理工程後の
タンタル凝集体を粉砕し、これにマグネシウムを添加
し、減圧下で低温熱処理を行う低温熱処理工程と、酸性
溶液でこれを洗浄する酸洗工程を有するタンタル粉末の
製法において、 高温熱処理工程を１０００℃以上、１２５０℃未満の温
度で行い、低温熱処理工程を７００℃〜１０００℃の温
度で行うことを特徴とするタンタル粉末の製法。1. A high-temperature heat treatment step in which potassium fluoride tantalate is sodium-reduced, and the obtained reduced tantalum powder is subjected to high-temperature heat treatment in an inert atmosphere, and a tantalum aggregate after the high-temperature heat treatment step is pulverized, and magnesium is added thereto. In a method of producing a tantalum powder having a low-temperature heat treatment step of performing low-temperature heat treatment under reduced pressure and a pickling step of washing the same with an acidic solution, the high-temperature heat treatment step is performed at a temperature of 1000 ° C. or more and less than 1250 ° C. A method for producing a tantalum powder, wherein the low-temperature heat treatment step is performed at a temperature of 700C to 1000C.
で還元する際、フッ化タンタル酸カリウムとナトリウム
とをそれぞれ溶融希釈塩中に少量ずつ分割して投入して
互いに反応させ、 ナトリウム添加直前における希釈塩量を、希釈塩内に投
入されたフッ化タンタル酸カリウムの常に４０〜１００
０倍とすることを特徴とする請求項１記載のタンタル粉
末の製法。2. When reducing potassium fluoride tantalate with sodium, potassium fluoride tantalate and sodium are each divided into small portions in a molten dilute salt and allowed to react with each other. The amount is always between 40 and 100 of the potassium fluorotantalate charged in the dilute salt.
2. The method for producing tantalum powder according to claim 1, wherein the ratio is 0 times.
2 ／ｇであることを特徴とする請求項１または２に記載
のタンタル粉末の製法。3. The reduced tantalum powder has a specific surface area of 2 to 5 m.
The method for producing tantalum powder according to claim 1 or 2, which is 2 / g.
で還元して得られた比表面積２〜５ｍ2 ／ｇの還元タン
タル粉末を不活性雰囲気下で高温熱処理し、ついで金属
マグネシウムを添加し、減圧下で低温熱処理を行って得
られたタンタル粉末であって、 このタンタル粉末を加圧成形して密度４．５〜５．０ｇ
／ｃｍ3 の成形体とし、この成形体を高温熱処理温度以
上の温度で真空焼結して、前記成形体の密度の１０３〜
１１５％の密度の焼結体とし、この焼結体をＥＩＡＪ
ＲＣ−２３６１に準拠して６０℃、１０Ｖで化成したも
のの比静電容量が８万〜２５万μＦＶ／ｇであることを
特徴とするタンタル粉末。4. A reduced tantalum powder having a specific surface area of 2 to 5 m 2 / g, obtained by reducing potassium fluorotantalate with sodium, is subjected to high-temperature heat treatment in an inert atmosphere, followed by addition of metallic magnesium and reduced pressure. Is a tantalum powder obtained by performing a low-temperature heat treatment at a pressure of 4.5 to 5.0 g.
/ Cm 3, and the formed body is vacuum-sintered at a temperature equal to or higher than the high-temperature heat treatment temperature, and has a density of 103 to
A sintered body having a density of 115% was obtained.
A tantalum powder characterized by having a specific capacitance of 80,000 to 250,000 [mu] FV / g, which is formed at 60 [deg.] C. and 10 V in accordance with RC-2361.
で還元して得られた比表面積２〜５ｍ2 ／ｇの還元タン
タル粉末を不活性雰囲気下で高温熱処理し、ついで金属
マグネシウムを添加し、減圧下で低温熱処理を行って得
られたタンタル粉末であって、 このタンタル粉末を加圧成形して密度４．５〜５．０ｇ
／ｃｍ3 の成形体とし、この成形体を高温熱処理温度以
上の温度で真空焼結して、前記成形体の密度の１０３〜
１１５％の密度の焼結体としたとき、真空焼結後の焼結
体の圧縮強度が真空焼結前の成形体の圧縮強度の３〜２
０倍となることを特徴とする請求項４に記載のタンタル
粉末。5. A reduced tantalum powder having a specific surface area of 2 to 5 m 2 / g, obtained by reducing potassium fluorotantalate with sodium, is subjected to a high-temperature heat treatment in an inert atmosphere, and then metallic magnesium is added thereto. Is a tantalum powder obtained by performing a low-temperature heat treatment at a pressure of 4.5 to 5.0 g.
/ Cm 3, and the formed body is vacuum-sintered at a temperature equal to or higher than the high-temperature heat treatment temperature, and has a density of 103 to
When the sintered body has a density of 115%, the compressive strength of the sintered body after vacuum sintering is 3 to 2 times the compressive strength of the compact before vacuum sintering.
The tantalum powder according to claim 4, wherein the tantalum powder becomes 0 times.
で還元して得られた比表面積２〜５ｍ2 ／ｇの還元タン
タル粉末を不活性雰囲気下で高温熱処理し、ついで金属
マグネシウムを添加し、減圧下で低温熱処理を行って得
られたタンタル粉末であって、 このタンタル粉末を加圧成形して密度４．５〜５．０ｇ
／ｃｍ3 の成形体とし、この成形体を高温熱処理温度以
上の温度で真空焼結して、前記成形体の密度の１０３〜
１１５％の密度の焼結体とし、この焼結体をＥＩＡＪ
ＲＣ−２３６１に準拠して６０℃、１０Ｖで化成したも
のの比静電容量が８万〜２５万μＦＶ／ｇであり、か
つ、６０℃、２０Ｖで化成したものの比静電容量が６０
℃、１０Ｖで化成したものの比静電容量の７０％以上で
あることを特徴とするタンタル粉末。6. A reduced tantalum powder having a specific surface area of 2 to 5 m 2 / g, obtained by reducing potassium fluorotantalate with sodium, is subjected to a high-temperature heat treatment in an inert atmosphere, followed by addition of metallic magnesium and reduced pressure. Is a tantalum powder obtained by performing a low-temperature heat treatment at a pressure of 4.5 to 5.0 g.
/ Cm 3, and the formed body is vacuum-sintered at a temperature equal to or higher than the high-temperature heat treatment temperature, and has a density of 103 to
A sintered body having a density of 115% was obtained.
According to RC-2361, the specific capacitance of the product formed at 60 ° C. and 10 V is 80,000 to 250,000 μFV / g, and the specific capacitance of the product formed at 60 ° C. and 20 V is 60.
A tantalum powder characterized by having a specific capacitance of 70% or more of that formed at 10 ° C.
のタンタル粉末から得られたことを特徴とするタンタル
電解コンデンサ。7. A tantalum electrolytic capacitor obtained from the tantalum powder according to claim 4. Description:
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000241612A JP4828016B2 (en) | 2000-08-09 | 2000-08-09 | Tantalum powder manufacturing method, tantalum powder and tantalum electrolytic capacitor |
| AU2001276746A AU2001276746A1 (en) | 2000-08-09 | 2001-08-07 | Method for producing tantalum powder, tantalum powder and tantalum electrolytic capacitor |
| PCT/JP2001/006768 WO2002011932A1 (en) | 2000-08-09 | 2001-08-07 | Method for producing tantalum powder, tantalum powder and tantalum electrolytic capacitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000241612A JP4828016B2 (en) | 2000-08-09 | 2000-08-09 | Tantalum powder manufacturing method, tantalum powder and tantalum electrolytic capacitor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2002206105A true JP2002206105A (en) | 2002-07-26 |
| JP4828016B2 JP4828016B2 (en) | 2011-11-30 |
Family
ID=18732777
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2000241612A Expired - Lifetime JP4828016B2 (en) | 2000-08-09 | 2000-08-09 | Tantalum powder manufacturing method, tantalum powder and tantalum electrolytic capacitor |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP4828016B2 (en) |
| AU (1) | AU2001276746A1 (en) |
| WO (1) | WO2002011932A1 (en) |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2007533854A (en) * | 2004-04-23 | 2007-11-22 | ハー ツェー シュタルク ゲゼルシャフト ミット ベシュレンクテル ハフツング ウント コンパニー コマンデイトゲゼルシヤフト | Method for producing niobium powder and tantalum powder |
| JP2008523241A (en) * | 2004-12-09 | 2008-07-03 | バイエル・ベタイリグングスフェアヴァルトゥング・ゴスラー・ゲゼルシャフト・ミット・ベシュレンクテル・ハフツング | Manufacture of valve metal powder |
| JP2008545887A (en) * | 2005-05-31 | 2008-12-18 | キャボット コーポレイション | Method for heat treatment of metal powder and product produced thereby |
| JP2009508006A (en) * | 2005-09-16 | 2009-02-26 | ハー．ツェー．スタルク ゲゼルシャフト ミット ベシュレンクテル ハフツング | Reduction method |
| JP2010150650A (en) * | 2008-11-27 | 2010-07-08 | Cabot Supermetal Kk | Method for producing agglomerated tantalum particles, tantalum pellet and capacitor |
| JP2010265520A (en) * | 2009-05-15 | 2010-11-25 | Cabot Supermetal Kk | Tantalum powdery mixture, method for producing the same, tantalum pellet, and method for producing the same |
| KR101115820B1 (en) | 2003-07-22 | 2012-03-09 | 하.체. 스타르크 게엠베하 | Process for Producing Capacitors |
| JP2012087371A (en) * | 2010-10-20 | 2012-05-10 | Cabot Supermetal Kk | Tantalum powder, method for producing the same, and deoxidation method |
| JP2014111840A (en) * | 2004-10-08 | 2014-06-19 | H.C. Starck Gmbh | Valve metal powder |
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| US7436652B2 (en) * | 2003-11-13 | 2008-10-14 | Showa Denko K.K. | Solid electrolyte capacitor |
| CN102554215B (en) * | 2011-12-29 | 2014-01-29 | 中国兵器工业第五二研究所 | Thermal treatment method for nanometer tantalum powder |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52107211A (en) * | 1976-03-05 | 1977-09-08 | Mitsui Mining & Smelting Co | Production of tantalum metal powder |
| JPS61284501A (en) * | 1985-06-10 | 1986-12-15 | Showa Kiyabotsuto Suupaa Metal Kk | Production of tantalum powder |
| JPS62278210A (en) * | 1986-03-04 | 1987-12-03 | キヤボツト コ−ポレ−シヨン | Production of condenser grade tantalum powder |
| JPH0897096A (en) * | 1994-09-28 | 1996-04-12 | Sutaruku Buitetsuku Kk | Tantalum powder and electrolytic capacitor employing it |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4684399A (en) * | 1986-03-04 | 1987-08-04 | Cabot Corporation | Tantalum powder process |
-
2000
- 2000-08-09 JP JP2000241612A patent/JP4828016B2/en not_active Expired - Lifetime
-
2001
- 2001-08-07 WO PCT/JP2001/006768 patent/WO2002011932A1/en active Application Filing
- 2001-08-07 AU AU2001276746A patent/AU2001276746A1/en not_active Abandoned
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52107211A (en) * | 1976-03-05 | 1977-09-08 | Mitsui Mining & Smelting Co | Production of tantalum metal powder |
| JPS61284501A (en) * | 1985-06-10 | 1986-12-15 | Showa Kiyabotsuto Suupaa Metal Kk | Production of tantalum powder |
| JPS62278210A (en) * | 1986-03-04 | 1987-12-03 | キヤボツト コ−ポレ−シヨン | Production of condenser grade tantalum powder |
| JPH0897096A (en) * | 1994-09-28 | 1996-04-12 | Sutaruku Buitetsuku Kk | Tantalum powder and electrolytic capacitor employing it |
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Also Published As
| Publication number | Publication date |
|---|---|
| JP4828016B2 (en) | 2011-11-30 |
| AU2001276746A1 (en) | 2002-02-18 |
| WO2002011932A1 (en) | 2002-02-14 |
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