NO126868B - - Google Patents
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- Publication number
- NO126868B NO126868B NO3056/70A NO305670A NO126868B NO 126868 B NO126868 B NO 126868B NO 3056/70 A NO3056/70 A NO 3056/70A NO 305670 A NO305670 A NO 305670A NO 126868 B NO126868 B NO 126868B
- Authority
- NO
- Norway
- Prior art keywords
- acid
- electrolyte
- container
- sulfuric
- maleic acid
- Prior art date
Links
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 claims description 20
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 20
- 239000003792 electrolyte Substances 0.000 claims description 19
- OFOBLEOULBTSOW-UHFFFAOYSA-N Propanedioic acid Natural products OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 claims description 12
- VZCYOOQTPOCHFL-UPHRSURJSA-N maleic acid Chemical compound OC(=O)\C=C/C(O)=O VZCYOOQTPOCHFL-UPHRSURJSA-N 0.000 claims description 12
- 239000011976 maleic acid Substances 0.000 claims description 12
- VZCYOOQTPOCHFL-UHFFFAOYSA-N trans-butenedioic acid Natural products OC(=O)C=CC(O)=O VZCYOOQTPOCHFL-UHFFFAOYSA-N 0.000 claims description 12
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 10
- 229910052782 aluminium Inorganic materials 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- 239000000203 mixture Substances 0.000 claims description 7
- 235000006408 oxalic acid Nutrition 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 4
- 150000007524 organic acids Chemical class 0.000 claims description 4
- 238000007743 anodising Methods 0.000 claims description 3
- 239000004927 clay Substances 0.000 claims description 2
- 235000005985 organic acids Nutrition 0.000 claims description 2
- 239000011148 porous material Substances 0.000 claims description 2
- 150000004760 silicates Chemical class 0.000 claims description 2
- 239000002689 soil Substances 0.000 claims description 2
- KDYFGRWQOYBRFD-UHFFFAOYSA-N succinic acid Chemical compound OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 description 10
- 238000002048 anodisation reaction Methods 0.000 description 6
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 6
- 239000001384 succinic acid Substances 0.000 description 4
- 238000007792 addition Methods 0.000 description 3
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- KDYFGRWQOYBRFD-NUQCWPJISA-N butanedioic acid Chemical compound O[14C](=O)CC[14C](O)=O KDYFGRWQOYBRFD-NUQCWPJISA-N 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- WXHLLJAMBQLULT-UHFFFAOYSA-N 2-[[6-[4-(2-hydroxyethyl)piperazin-1-yl]-2-methylpyrimidin-4-yl]amino]-n-(2-methyl-6-sulfanylphenyl)-1,3-thiazole-5-carboxamide;hydrate Chemical compound O.C=1C(N2CCN(CCO)CC2)=NC(C)=NC=1NC(S1)=NC=C1C(=O)NC1=C(C)C=CC=C1S WXHLLJAMBQLULT-UHFFFAOYSA-N 0.000 description 1
- SDGNNLQZAPXALR-UHFFFAOYSA-N 3-sulfophthalic acid Chemical compound OC(=O)C1=CC=CC(S(O)(=O)=O)=C1C(O)=O SDGNNLQZAPXALR-UHFFFAOYSA-N 0.000 description 1
- YCPXWRQRBFJBPZ-UHFFFAOYSA-N 5-sulfosalicylic acid Chemical compound OC(=O)C1=CC(S(O)(=O)=O)=CC=C1O YCPXWRQRBFJBPZ-UHFFFAOYSA-N 0.000 description 1
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 150000001991 dicarboxylic acids Chemical class 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000002386 leaching Methods 0.000 description 1
- 150000002689 maleic acids Chemical class 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
- C25D11/02—Anodisation
- C25D11/04—Anodisation of aluminium or alloys based thereon
- C25D11/14—Producing integrally coloured layers
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D11/00—Electrolytic coating by surface reaction, i.e. forming conversion layers
- C25D11/005—Apparatus specially adapted for electrolytic conversion coating
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D17/00—Constructional parts, or assemblies thereof, of cells for electrolytic coating
- C25D17/002—Cell separation, e.g. membranes, diaphragms
Description
Fremgangsmåte ved fargeanodisering av aluminiumgjenstander. Procedure for color anodizing of aluminum objects.
OppfinnelsBn vedrorer en fremgangsmåte ved fargeanodisering av aluminiumgjenstander i en elektrolytt på basis av maleinsyre, som dessuten inneholder mindre mengder av svovel- og eventuelt oksalsyre. The invention relates to a method for color anodizing of aluminum objects in an electrolyte based on maleic acid, which also contains smaller amounts of sulfuric and possibly oxalic acid.
Fargede oksydsjikt kan man frembringe i kjente elektrolytter som består av vandige opplosninger av sulfonsyrer (f.eks. sulfosalicylsyre, sulfoftalsyre) eller også av dikarboksylsyrer med eventuelt mindre tilsetninger av svovelsyre. Av sistnevnte gruppe er av spesiell ■ interesse en elektrolytt på basis av maleinsyre med tilsetninger av oksal- og svovelsyre på grunn av de små omkostninger ved badansetningen samt jevnheten av de ved forholds- Colored oxide layers can be produced in known electrolytes which consist of aqueous solutions of sulphonic acids (e.g. sulphosalicylic acid, sulphophthalic acid) or also of dicarboxylic acids with possibly minor additions of sulfuric acid. Of the latter group, an electrolyte based on maleic acid with additions of oxalic and sulfuric acid is of special ■ interest because of the small costs of the bath composition as well as the uniformity of the
vis lave spenninger oppnåelige fargetoner som rekker fra lyse- show low voltages attainable hues ranging from light-
brunt til mSrkegrått og sort. brown to dark gray and black.
En viss ulempe ved en .overveiende umettet maleinsyre-holdig elektrolytt består imidlertid i at ved hjelp av det ved katoden utskilte hydrogen omdannes en betraktelig del av malein- However, a certain disadvantage of a predominantly unsaturated maleic acid-containing electrolyte consists in the fact that with the help of the hydrogen released at the cathode, a considerable part of the maleic acid is converted
syren til ravsyre. På grunn av ravsyrens relativt lille opploselig-het krystalliserer denne ut ved åpningene av de for badsirkulering hodvendige pressluftledninger samt på de til badkjoling nodvendige kjoleslanger. Folgelig er det nodvendig å regenerere badet etter passering av 5 - 10 dm p aluminiumoverflate pr. 1 badinnhold ved at enten avkjoles hele badet, eller i det minste en betraktelig del herav rundt 10 - 20°C i forhold til arbeidstemperaturen (20 - 30°C) the acid to succinic acid. Due to the relatively low solubility of succinic acid, it crystallizes out at the openings of the compressed air lines required for bath circulation and on the gown hoses required for bath robes. Consequently, it is necessary to regenerate the bath after passing 5 - 10 dm on the aluminum surface per 1 bath content by either cooling the entire bath, or at least a considerable part of it around 10 - 20°C in relation to the working temperature (20 - 30°C)
og den utfelte ravsyre fjernes. Dessuten må elektrolyttens opp-rinnelige konsentrasjon gjeninnstilles ved tilsetning av an tilsvarende maleinsyremengde. and the precipitated succinic acid is removed. Moreover, the original concentration of the electrolyte must be reset by adding a corresponding amount of maleic acid.
Ved fremgangsmåten ifolge oppfinnelsen lar dannelsen av ravsyre seg omtrent fullstendig unngå ved at katodene anbringes atskilt fra anoderommet i en kasse eller rorformet beholder hvis vegg består av et finporet ionegjennomtrengelig material f diafragma) In the method according to the invention, the formation of succinic acid can be almost completely avoided by placing the cathodes separately from the anode space in a box or tube-shaped container whose wall consists of a finely pored ion-permeable material (diaphragm)
og som inneholder en elektrolytt med en elektrisk godt ledende organisk syre eller en blanding av organiske syrer med små mengder av svovelsyre. and which contains an electrolyte with an electrically conductive organic acid or a mixture of organic acids with small amounts of sulfuric acid.
Som material for en slik beholder er det f.eks. egnet en ved h5ye temperaturer brent blanding av leirjordsilikater hvis porevidde utgjor ca. 1 ^um. Ved veggtykkelser mellom fortrinnsvis 3 og 10 mm har en slik beholder en tilstrekkelig mekanisk fasthet og har samtidig en lav elektrisk motstand. Overflaten av beholder- As material for such a container, there is e.g. suitable is a mixture of clay soil silicates fired at high temperatures whose pore width is approx. 1 µm. With wall thicknesses of preferably between 3 and 10 mm, such a container has sufficient mechanical strength and at the same time has a low electrical resistance. The surface of container-
en resp. den samlede overflate av et batteri av paralleltkoplede beholdere skal derved dimensjoneres således at strømtettheten ikke overskrider 3 ampere/dm . a resp. the overall surface of a battery of parallel-connected containers must thereby be dimensioned so that the current density does not exceed 3 amperes/dm.
Konsentrasjonen av den elektrolytt som befinner seg i beholderen skal hensiktsmessig vjere så hoy at minst mulig maleinsyre inndiffunderer. Egnede elektrolyttblandinger er eksempelvis 3 til 8 vektprosent oksalsyre og 0,2 til 1 vektprosent svovelsyre eller også 5-30 vektprosent sitronsyre resp. sulfosalicylsyre med tilsetninger av svovelsyre i samme mengder. Slike elektrolyttblandinger har ved siden'av tallrike andre, som i og for seg også er mulige, den fordel at i tilfelle en beskadigelse av beholderen, inntrer ingen vesentlig endring av egenskapen av den eksempelvis av 20 vektprosent maleinsyre, 1 vektprosent oksalsyre, 0,4 vektprosent svovelsyre, resten vann, bestående elektrolytt i anoderommet. The concentration of the electrolyte in the container should suitably be so high that as little as possible of maleic acid diffuses in. Suitable electrolyte mixtures are, for example, 3 to 8 weight percent oxalic acid and 0.2 to 1 weight percent sulfuric acid or also 5-30 weight percent citric acid or sulfosalicylic acid with additions of sulfuric acid in the same quantities. Such electrolyte mixtures, in addition to numerous others, which in and of themselves are also possible, have the advantage that in the event of damage to the container, no significant change occurs in its properties, for example of 20 weight percent maleic acid, 1 weight percent oxalic acid, 0.4 weight percent sulfuric acid, the rest water, consisting of electrolyte in the anode compartment.
Som ytterligere overraskende fordel ved en anordning av As a further surprising advantage of a device of
den oppfinnelsesmessige type har det vist seg, at en vesentlig del av det under den anodiske oksydasjon i badet opploste aluminium, in the inventive type, it has been shown that a significant part of the aluminum dissolved during the anodic oxidation in the bath,
som i samsvar med teknikkens stand fjernes ved ioneutveksler, sam- which, in accordance with the state of the art, is removed by ion exchangers, together
ler seg i katodebeholderne uten å hindre anodisasjonsprosessen. Levetid av et slikt bad okes derfor. settles in the cathode containers without hindering the anodization process. The lifespan of such a bath is therefore increased.
Ved den omtalte anordning oppnås at deler av renaluminium såvel som av de kjente for fargeanodisering egnede aluminiumlegeringer kan anodiseres i elektrolytter på basis av maleinsyre vesentlig mere okonomisk. Den uten regnerering av badet mulige gjennomfør- With the mentioned device, it is achieved that parts of pure aluminum as well as of the known aluminum alloys suitable for color anodization can be anodized in electrolytes based on maleic acid significantly more economically. The possible implementation without calculation of the bathroom
ing okes alt etter arbeidsbetingelsene med 10 til 50 ganger. Nød-vendigheten av å tilsette ny maleinsyre bortfaller inntil komplet-tering av utslepningstap. ing is increased depending on the working conditions by 10 to 50 times. The need to add new maleic acid ceases to exist until leaching losses are completed.
Folgende eksempel skal tjene til å forklare det oppnådde tekniske fremskritt. I en elektrolytt bestående av 20 vektprosent maleinsyre, 1 vektprosent oksalsyre og 0,4 vektprosent svovelsyre hvori det ble eloksert pressprofiler av en AlMgSi 0,5-legering i en morkebrun fargetone, var det ved anvendelse av katodeblikk av aluminium som stod i direkte berSring med elektrolytten nodvendig å gjennomfore regenereringen etter en produksjon på hver gang 6 dm /l badinnhold. Ble derimot katoder av samme type anbragt i en at- The following example will serve to explain the technical progress achieved. In an electrolyte consisting of 20% by weight maleic acid, 1% by weight oxalic acid and 0.4% by weight sulfuric acid in which press profiles of an AlMgSi 0.5 alloy were anodized in a dark brown hue, using cathode tin of aluminum in direct contact with the electrolyte necessary to carry out the regeneration after a production of 6 dm/l bath content each time. If, on the other hand, cathodes of the same type were placed in an at-
skilt beholder som inneholder en elektrolytt med 20 vektprosent sitronsyre og 0,4 vektprosent svovelsyre', så dannet det seg i anoderommet også etter en gjennomføring på 100 dm /l badinnhold bare en mindre for fargeanodisasjonen uskadelig mengde av ravsyre. I katoderommet ble det etter denne tid riktignok fastslått et innhold av 8% opplSst og 5$ utkrystallisert ravsyre (omdannelse av indifundert maleinsyre), imidlertid hindrer dette ikke den videre fargeanodisa-sjon. Dessuten oker aliminiuminnholdet betraktelig i katoderommet. Det ble fjernet ca. 40 % av det under fargeanodisasjonen i anoderommet opplost aluminium herifra. I forhold til den tidligere fremgangsmåte behovde tilsvarende mindre aluminium å fjernes ved ione-utveksling. Etter fornyelse av den i forhold til badinnholdet mindre elektrolyttmengde i katoderommet kunne det fargeanodiseres som tidligere. Ved overholdelse av en strSmtetthet på ca. 2 ampere/dm separated container containing an electrolyte with 20% by weight of citric acid and 0.4% by weight of sulfuric acid', then even after a passage of 100 dm/l bath content, only a small amount of succinic acid, harmless for the color anodization, formed in the anode compartment. After this time, a content of 8% dissolved and 5% crystallized succinic acid (conversion of undiluted maleic acid) was determined in the cathode compartment, however, this does not prevent further color anodisation. In addition, the aluminum content increases considerably in the cathode space. It was removed approx. 40% of the aluminum dissolved during the color anodization in the anode compartment from here. Compared to the previous method, correspondingly less aluminum needed to be removed by ion exchange. After renewing the smaller amount of electrolyte in the cathode compartment in relation to the bath content, color anodization could be carried out as before. In compliance with a strSm density of approx. 2 amps/dm
overflate av diafragmabeholderen var spenningen bare ca. 4 volt hoyere enn ved ellers lik arbeidsmåte uten.anvendelse av beholderen. surface of the diaphragm container, the voltage was only approx. 4 volts higher than with an otherwise identical working method without using the container.
En innretning til utforelse av fremgangsmåten ifolge oppfinnelsen er eksempelvis skjematisk vist på tegningen. Her befinner det seg i en beholder anoden 1, dvs. en gjenstand som skal utstyres med et farget overtrekk, videre katoden 2, som er omgitt av diafragma 4» Med 3 er det betegnet den vandige elektrolytt, som eksempelvis består av 20 vektprosent maleinsyre, 1 vektprosent oksalsyre, 0,4 vektprosent svovelsyre, resten vann. Diafragmaelektrolytten har referansetallet 5» Katoden 2 har åpning-er 6 hvorigjennom hydrogenet trer inn i katodens indre og kan unn-vike oppad. A device for carrying out the method according to the invention is, for example, schematically shown in the drawing. Here, the anode 1, i.e. an object to be equipped with a colored covering, is located in a container, and the cathode 2, which is surrounded by a diaphragm 4" 3 denotes the aqueous electrolyte, which for example consists of 20% maleic acid by weight, 1% by weight oxalic acid, 0.4% by weight sulfuric acid, the rest water. The diaphragm electrolyte has the reference number 5". The cathode 2 has openings 6 through which the hydrogen enters the interior of the cathode and can escape upwards.
Claims (2)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1950716A DE1950716C3 (en) | 1969-10-08 | 1969-10-08 | Process and device for color anodizing of aluminum materials |
Publications (1)
Publication Number | Publication Date |
---|---|
NO126868B true NO126868B (en) | 1973-04-02 |
Family
ID=5747642
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NO3056/70A NO126868B (en) | 1969-10-08 | 1970-08-10 |
Country Status (14)
Country | Link |
---|---|
US (1) | US3770600A (en) |
JP (1) | JPS5010696B1 (en) |
AT (1) | AT292409B (en) |
BE (1) | BE754994A (en) |
CA (1) | CA947230A (en) |
CH (1) | CH541628A (en) |
DE (1) | DE1950716C3 (en) |
FR (1) | FR2064187B1 (en) |
GB (2) | GB1319659A (en) |
LU (1) | LU61309A1 (en) |
NL (1) | NL7014669A (en) |
NO (1) | NO126868B (en) |
SE (1) | SE367441B (en) |
ZA (1) | ZA706579B (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5367196A (en) * | 1992-09-17 | 1994-11-22 | Olin Corporation | Molded plastic semiconductor package including an aluminum alloy heat spreader |
US5608267A (en) * | 1992-09-17 | 1997-03-04 | Olin Corporation | Molded plastic semiconductor package including heat spreader |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1430561A (en) * | 1965-03-03 | 1966-03-04 | Vaw Ver Aluminium Werke Ag | Process for obtaining colored oxide layers on aluminum or aluminum alloy parts |
GB1233582A (en) * | 1967-07-20 | 1971-05-26 | ||
NL6912194A (en) * | 1968-08-14 | 1970-02-17 |
-
0
- BE BE754994D patent/BE754994A/en not_active IP Right Cessation
-
1969
- 1969-10-08 DE DE1950716A patent/DE1950716C3/en not_active Expired
-
1970
- 1970-06-12 GB GB2865972A patent/GB1319659A/en not_active Expired
- 1970-07-10 LU LU61309D patent/LU61309A1/xx unknown
- 1970-07-13 AT AT635070A patent/AT292409B/en not_active IP Right Cessation
- 1970-07-16 CH CH1082970A patent/CH541628A/en not_active IP Right Cessation
- 1970-08-10 NO NO3056/70A patent/NO126868B/no unknown
- 1970-09-01 FR FR7031808A patent/FR2064187B1/fr not_active Expired
- 1970-09-28 ZA ZA706579A patent/ZA706579B/en unknown
- 1970-09-30 GB GB4656470A patent/GB1319658A/en not_active Expired
- 1970-10-06 NL NL7014669A patent/NL7014669A/xx unknown
- 1970-10-07 JP JP45087584A patent/JPS5010696B1/ja active Pending
- 1970-10-07 SE SE13601/70A patent/SE367441B/xx unknown
- 1970-10-08 CA CA95122A patent/CA947230A/en not_active Expired
- 1970-10-08 US US00079242A patent/US3770600A/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
GB1319658A (en) | 1973-06-06 |
CH541628A (en) | 1973-09-15 |
FR2064187A1 (en) | 1971-07-16 |
DE1950716A1 (en) | 1971-04-22 |
NL7014669A (en) | 1971-04-14 |
GB1319659A (en) | 1973-06-06 |
US3770600A (en) | 1973-11-06 |
DE1950716C3 (en) | 1979-05-23 |
AT292409B (en) | 1971-08-25 |
JPS5010696B1 (en) | 1975-04-23 |
LU61309A1 (en) | 1970-09-10 |
SE367441B (en) | 1974-05-27 |
CA947230A (en) | 1974-05-14 |
DE1950716B2 (en) | 1978-09-28 |
FR2064187B1 (en) | 1975-01-10 |
ZA706579B (en) | 1971-05-27 |
BE754994A (en) | 1971-02-01 |
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