|Publication number||US2851385 A|
|Publication date||Sep 9, 1958|
|Filing date||Apr 3, 1952|
|Priority date||Apr 3, 1952|
|Also published as||DE977586C|
|Publication number||US 2851385 A, US 2851385A, US-A-2851385, US2851385 A, US2851385A|
|Inventors||Newhard Jr Nelson James, Spruance Jr Frank Palin|
|Original Assignee||Amchem Prod|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (7), Referenced by (55), Classifications (8)|
|External Links: USPTO, USPTO Assignment, Espacenet|
nited States PatentO "lce PROCESS AND COMPOSITION FOR COATING ALUMINUM SURFACES Frank Palin Spruance, Jr., Ambler, and Nelson James Newhard, Jr., Oreland, Pa., assignors to Amchem Products, Inc., a corporation of Delaware No Drawing. Application April 3, 1952 Serial No. 280,364
2 Claims. (Cl. 1486.2)
This invention relates to the art of producing a chemically bonded chromate conversion coating on surfaces of aluminum or alloys thereof in which aluminum is the principal or predominant ingredient.
The principal object of the invention is to render aluminum surfaces highly resistant to corrosion regardless of whether or not the coated surface is subsequently given a finish of paint, lacquer, enamel, japan or the like.
Herefore, it has been known that the durability and corrosion resistance of aluminum surfaces even under abnormally severe corrosive conditions can be improved by forming thereon a chemically bonded chi-ornate conversion coating by subjecting them to the action of an aqueous acid solution of hexavalent chromium and fluorine-bearing compounds, such as hydrofluoric acid, hydrofiuosilicic acid, fluoboric acid and their soluble salts. Specific examples of such processes are described in United States Patents Nos. 2,276,353 and 2,507,956, and such processes are now very generally known to those skilled in this art as chromate conversion coverings.
The present invention is based upon the discovery that the corrosion resistance which can be imparted to surfaces of aluminum by treatments of the character just described can be still further enhanced if there be added to the baths which are employed in producing the coat-# ing ions of metal from the class consisting of zirconium, titanium and tin. Moreover, the use of such metal additions to coating baths of the character described makes it possible to operate the baths at considerably lower temperatures than has heretofore been customary. Indeed, with our invention, it is even possible to produce coatings at room temperature or lower. By room temperature is meant average living temperature, which is in the neighborhood of 72 F.
The form in which the dissolved zirconium, titanium or tin is introduced into the coating bath appears to make little or no difference so long as the composition of the solution is not otherwise adversely disturbed. For example, these metals should not be introduced along with reducing agents which would cause a loss of hexavalent chromium by the reduction thereof to trivalent chromium. We have found it very desirable to introduce the metals as fluozirconic acid, fluotitanic acid, fluostannic acid or soluble salts of such acids, etc. Indeed, as an actual matter of fact, their introduction as fluorine acids is highly desirable because when so introduced they serve as a source of fluorine.
There is no minimum limit for concentration of the metals in the operating bath because an improvement is achieved even when using only very small amounts. Furthermore, as far as we can ascertain, excess amounts appear to do no harm but, generally speaking, in the interest of economy, we prefer to use from 0.1 to 7.0 grams of the metal per liter of operating bath.
By way of specific example we cite the following:
2,851,385. Patented Sept. 9, 1958 2 Formula No. 1
G. Chromic d 1 6 Potassium zirconium fluoride 2.5 Ammonium borofluoridenr 7.6
Water to make 1 liter.
Other representative bath formulae which can be employed with our invention are as follows:
Formula N 0. 2
Chromic acid- 1 I a a.. v 8.4 Potassium zirconium fluoride 3.5 Boric acid 6.3 Ammonium bifluoride 4.0 Water to make 1 liter.
F orm ula No. 3
G. Chromic acid 8 Hydrofluoric acid 2.5 23% titanium trichloride 3.2 Water to make 1 liter.
4.5 ml. of 48% acid.
Formula N0. 4
Ammonium bifluoride 2.7 Chromic acid 6 Stannic chloride (SnC1 4.4 Water to make 1 liter.
Formula No. 5
G. Diammoniumsilicofluoride (NHqJgslFs 14 Chromic acid--- 10 Zirconium nitrate Zr(NO .5H O 12 Water to make 1 liter.
If desired, mixtures of the metals may be used. For instance, in Formula No. 4 as given above the amount of stannic chloride used may be reduced by means of additions of titanium trichloride or of zirconium nitrate or both.
In carrying out our improved process the surface to be coated should first be cleaned. The cleaning, which forms no part of the present invention, may be carried out by conventional methods. For instance, grease and dirt may be removed by dipping into a mild silicate alkali bath or by the use of an emulsion of a grease solvent. The clean work, either wet or dry, may be treated with a solution of the character described, such for example as the solutions of the formulae given above.
The treatment may be given by immersing the surface to be coated in the solution, by flowing or spraying the solution on the work or by any other convenient technique in which the solution is allowed to act upon the work. For example, if the solution of Formula No. 1 is used in a dip installation, it may be heated to approxi mately F. and the clean work immersed in it for approximately 30 seconds to 2 minutes. Upon rem-oval from the solution the article may be rinsed with clean water and dried and afterwards painted, if desired. Sometimes the rinsing may be done with a dilute solution of Formula No. 1, after which the article may be dried and then painted. Or, if the piece is not to be painted, it may simply be removed from the solution and dried.
As mentioned above, our invention makes it possible to operate with baths at considerably lower temperatures than has been possible heretofore. For instance, in prior practice coating baths of silico-fluoride and chromic acid have been used hot,fi. e., at or near the boiling point. With our solutions thisis not necessary, although some slight increase in temperature may be employed if desired because of the greater rapidity of the resulting actioiif Nevertheless, and by way 'of-specific example, Form'ulfNo. 5 as given above will produce excellent corrosion resistant coatings if the cleaned article is immersed in the bath for a period of 1 to 2 minutes at a temperature not exceeding 80 F. Subject to minor variations the formulas of the other examples will yield comparable results as to temperature and time of treatment needed to produce good coatings. This is a marked and very valuable advantage of our invention.
1. In the art of producing a chromate conversion coating on surfaces of aluminum and alloys thereof in which aluminum is the predominant ingredient by treating the surface with an aqueous acid bath of the type which consists essentially of hexavalent chromium and fluorine in proportions capable of producing such a coating; the method which comprises including in the bath, as an addition agent, metal ions from the group consisting of zirconium, titanium and stannic tin in a quantity sufficient References Cited in the file of this patent UNITED STATES PATENTS 1,939,421 Tosterud Dec. 12, 1933 1,957,354 Prier May 1, 1934 2,276,353 Thompson Mar. 7, 1942 2,312,855 Thompson Mar. 2, 1943 2,348,698 Thompson May 9, 1944 2,357,219 Mott Aug. 29, 1944 FOREIGN PATENTS 546,466 Germany Mar. 12, 1932
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1939421 *||May 26, 1932||Dec 12, 1933||Aluminum Co Of America||Coating|
|US1957354 *||Apr 26, 1932||May 1, 1934||Pierre Prier||Process of protecting light metals against corrosion|
|US2276353 *||Sep 28, 1935||Mar 17, 1942||Parker Rust Proof Co||Process of coating|
|US2312855 *||Sep 7, 1940||Mar 2, 1943||Parker Rust Proof Co||Method of coating aluminum|
|US2348698 *||Aug 3, 1940||May 9, 1944||Parker Rust Proof Co||Method of roller coating|
|US2357219 *||Jan 10, 1942||Aug 29, 1944||Joseph P Moran||Corrosion-resistant ferrous alloys|
|DE546466C *||Feb 26, 1929||Mar 12, 1932||Otto Sprenger Patentverwertung||Verfahren zur Herstellung von Manganoxyde enthaltenden UEberzuegen auf Aluminium, Magnesium und ihren Legierungen|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US2957784 *||Sep 18, 1958||Oct 25, 1960||Wolverine Fabricating & Mfg Co||Gasket material and method of producing the same|
|US3018211 *||Jan 26, 1959||Jan 23, 1962||Purex Corp Ltd||Composition and process for brightening aluminum and its alloys|
|US3066055 *||Nov 10, 1958||Nov 27, 1962||Purex Corp Ltd||Process and composition for producing aluminum surface conversion coatings|
|US3113051 *||Sep 29, 1961||Dec 3, 1963||Purex Corp Ltd||Process and composition for producing aluminum surface conversion coatings|
|US3159509 *||Nov 27, 1961||Dec 1, 1964||Okuno Chemical Industry Compan||Chromate process|
|US3380858 *||Nov 10, 1964||Apr 30, 1968||Hooker Chemical Corp||Chromate coating composition for aluminum and process|
|US3494839 *||Jan 23, 1967||Feb 10, 1970||Amchem Prod||Method of sealing chromic acid anodized aluminum surfaces|
|US4063969 *||Feb 9, 1976||Dec 20, 1977||Oxy Metal Industries Corporation||Treating aluminum with tannin and lithium|
|US4111722 *||Feb 9, 1976||Sep 5, 1978||Oxy Metal Industries Corporation||Tannin treatment of aluminum with a fluoride cleaner|
|US4971636 *||Jun 21, 1989||Nov 20, 1990||Nkk Corporation||Method of producing highly corrosion-resistant surface-treated steel plates|
|US5123978 *||Mar 19, 1991||Jun 23, 1992||The United States Of America As Represented By The Secretary Of The Navy||Corrosion resistant chromate conversion coatings for heat-treated aluminum alloys|
|US5401334 *||May 4, 1993||Mar 28, 1995||Titeflex Corporation||Fluoropolymer aluminum laminate|
|US5531841 *||Nov 4, 1994||Jul 2, 1996||Titeflex Corporation||Fluoropolymer aluminum laminate|
|US5547906 *||Jul 13, 1994||Aug 20, 1996||Badehi; Pierre||Methods for producing integrated circuit devices|
|US5702759 *||Jun 7, 1995||Dec 30, 1997||Henkel Corporation||Applicator for flowable materials|
|US5716759 *||Sep 1, 1994||Feb 10, 1998||Shellcase Ltd.||Method and apparatus for producing integrated circuit devices|
|US6010263 *||Sep 22, 1997||Jan 4, 2000||Henkel Corporation||Applicator for flowable materials|
|US6040235 *||Jan 10, 1995||Mar 21, 2000||Shellcase Ltd.||Methods and apparatus for producing integrated circuit devices|
|US6048921 *||Aug 12, 1997||Apr 11, 2000||Henkel Corporation||Method for applying conversion coating with wick applicator|
|US6117707 *||Jul 29, 1996||Sep 12, 2000||Shellcase Ltd.||Methods of producing integrated circuit devices|
|US6646289||Feb 3, 1999||Nov 11, 2003||Shellcase Ltd.||Integrated circuit device|
|US6777767||Nov 29, 2000||Aug 17, 2004||Shellcase Ltd.||Methods for producing packaged integrated circuit devices & packaged integrated circuit devices produced thereby|
|US6972480||Jun 16, 2003||Dec 6, 2005||Shellcase Ltd.||Methods and apparatus for packaging integrated circuit devices|
|US7033664||Oct 22, 2002||Apr 25, 2006||Tessera Technologies Hungary Kft||Methods for producing packaged integrated circuit devices and packaged integrated circuit devices produced thereby|
|US7144745||Aug 7, 2001||Dec 5, 2006||Tessera Technologies Hungary Kft.||Methods for producing packaged integrated circuit devices and packaged integrated circuit devices produced|
|US7157742||Mar 11, 2003||Jan 2, 2007||Tessera Technologies Hungary Kft.||Integrated circuit device|
|US7192796||Jul 2, 2004||Mar 20, 2007||Tessera Technologies Hungary Kft.||Methods and apparatus for packaging integrated circuit devices|
|US7224056||Sep 24, 2004||May 29, 2007||Tessera, Inc.||Back-face and edge interconnects for lidded package|
|US7265440||May 10, 2005||Sep 4, 2007||Tessera Technologies Hungary Kft.||Methods and apparatus for packaging integrated circuit devices|
|US7408249||Dec 19, 2001||Aug 5, 2008||Tessera Technologies Hungary Kft.||Packaged integrated circuits and methods of producing thereof|
|US7479398||Aug 21, 2007||Jan 20, 2009||Tessera Technologies Hungary Kft.||Methods and apparatus for packaging integrated circuit devices|
|US7495341||Jan 30, 2007||Feb 24, 2009||Tessera Technologies Hungary Kft.||Methods and apparatus for packaging integrated circuit devices|
|US7566853||Dec 23, 2005||Jul 28, 2009||Tessera, Inc.||Image sensor employing a plurality of photodetector arrays and/or rear-illuminated architecture|
|US7566955||Aug 28, 2002||Jul 28, 2009||Tessera, Inc.||High-frequency chip packages|
|US7642629||Aug 13, 2007||Jan 5, 2010||Tessera Technologies Hungary Kft.||Methods and apparatus for packaging integrated circuit devices|
|US7781240||Aug 24, 2010||Tessera Technologies Hungary Kft.||Integrated circuit device|
|US7936062||Jan 19, 2007||May 3, 2011||Tessera Technologies Ireland Limited||Wafer level chip packaging|
|US7939918||May 10, 2011||Tessera Technologies Ireland Limited||Chip packages with covers|
|US8143095||Mar 27, 2012||Tessera, Inc.||Sequential fabrication of vertical conductive interconnects in capped chips|
|US8592831||Oct 26, 2006||Nov 26, 2013||Invensas Corp.||Integrated circuit device|
|US8604605||Jan 5, 2007||Dec 10, 2013||Invensas Corp.||Microelectronic assembly with multi-layer support structure|
|US20010018236 *||Nov 29, 2000||Aug 30, 2001||Shellcase Ltd.||Methods for producing packaged integrated circuit devices & packaged integrated circuit devices produced thereby|
|US20020027296 *||Aug 7, 2001||Mar 7, 2002||Badehi Avner Pierre||Methods for producing packaged integrated circuit devices & packaged integrated circuit devices produced thereby|
|US20030151124 *||Mar 11, 2003||Aug 14, 2003||Shellcase, Ltd.||Integrated circuit device|
|US20040183185 *||Dec 19, 2001||Sep 23, 2004||Avner Badihi||Packaged integrated circuits and methods of producing thereof|
|US20040251525 *||Jun 16, 2003||Dec 16, 2004||Shellcase Ltd.||Methods and apparatus for packaging integrated circuit devices|
|US20050104179 *||Jul 2, 2004||May 19, 2005||Shellcase Ltd.||Methods and apparatus for packaging integrated circuit devices|
|US20050205977 *||May 10, 2005||Sep 22, 2005||Shellcase Ltd.||Methods and apparatus for packaging integrated circuit devices|
|US20070013044 *||Dec 19, 2001||Jan 18, 2007||Avner Badihi||Packaged integrated circuits and methods of producing thereof|
|US20070034777 *||Dec 23, 2005||Feb 15, 2007||Tessera, Inc.||Image sensor employing a plurality of photodetector arrays and/or rear-illuminated architecture|
|US20070040180 *||Oct 26, 2006||Feb 22, 2007||Tessera Technologies Hungary Kft.||Integrated circuit device|
|US20070040257 *||Oct 26, 2006||Feb 22, 2007||Tessera Technologies Hungary Kft.||Chip packages with covers|
|US20070042562 *||Oct 26, 2006||Feb 22, 2007||Tessera Technologies Hungary Kft.||Integrated circuit device|
|US20100323475 *||Aug 20, 2010||Dec 23, 2010||Tessera Technologies Hungary Kft..||Integrated circuit device|
|EP2381478A2||Feb 3, 1999||Oct 26, 2011||Tessera Technologies Hungary Kft.||Integrated circuit device|
|International Classification||C23C22/05, C23C22/38, C23C22/37|
|Cooperative Classification||C23C22/38, C23C22/37|
|European Classification||C23C22/38, C23C22/37|