US3243321A - Method of teflon coating of metals - Google Patents

Method of teflon coating of metals Download PDF

Info

Publication number
US3243321A
US3243321A US23512662A US3243321A US 3243321 A US3243321 A US 3243321A US 23512662 A US23512662 A US 23512662A US 3243321 A US3243321 A US 3243321A
Authority
US
United States
Prior art keywords
grit
surfaces
coating
aluminum
blanks
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.)
Expired - Lifetime
Application number
Inventor
Ronald P Rowand
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Atlas Corp
Atlas Copco AB
Original Assignee
Atlas Copco AB
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Atlas Copco AB filed Critical Atlas Copco AB
Priority to US23512662 priority Critical patent/US3243321A/en
Application granted granted Critical
Publication of US3243321A publication Critical patent/US3243321A/en
Anticipated expiration legal-status Critical
Application status is Expired - Lifetime legal-status Critical

Links

Classifications

    • AHUMAN NECESSITIES
    • A21BAKING; EDIBLE DOUGHS
    • A21DTREATMENT, e.g. PRESERVATION, OF FLOUR OR DOUGH, e.g. BY ADDITION OF MATERIALS; BAKING; BAKERY PRODUCTS; PRESERVATION THEREOF
    • A21D8/00Methods for preparing or baking dough
    • A21D8/08Prevention of sticking, e.g. to baking plates
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05DPROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D3/00Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
    • B05D3/10Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by other chemical means
    • B05D3/102Pretreatment of metallic substrates
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05DPROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D5/00Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
    • B05D5/08Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures to obtain an anti-friction or anti-adhesive surface
    • B05D5/083Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures to obtain an anti-friction or anti-adhesive surface involving the use of fluoropolymers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05DPROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D2202/00Metallic substrate
    • B05D2202/20Metallic substrate based on light metals
    • B05D2202/25Metallic substrate based on light metals based on Al
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B05SPRAYING OR ATOMISING IN GENERAL; APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05DPROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D2350/00Pretreatment of the substrate
    • B05D2350/30Change of the surface
    • B05D2350/33Roughening
    • B05D2350/38Roughening by mechanical means

Description

United States Patent 3,243,321 METHOD OF TEFLON COATING 0F METALS Ronald P. Rowand, Longmeadow, Mass., assignor to Atlas Corporation, New York, N.Y., a corporation of Delaware No Drawing. Filed Nov. 2, 1962, Ser. No. 235,126 2 Claims. (Cl. 148-627) This invention relates to the coating of metal surfaces 'with polytetrafluoroethylene, commonly known by the Du Pont Company trademark Teflon by which name it will be hereinafter referred to.

More particularly the invention is related to the Tefloncoating of aluminum blanks to be formed into cooking utensils such as fry pans, griddles, roasters, sauce pans,

cookie sheets, and the like, and a primary object is to provide an improved method of preparing the metal for the application of transparent Teflon coatings not only to insure good adhesion of the coating but also to impart an improved appearance to the finished utensil, the appearance being characterized by a bright and unusually light coloration.

Particular features of the method are the use of an iron grit for blasting the surface of the metal and increasing the surface area per square inch of the blank, a deoxidization cleaning step prior to coating, and the use of a nearly transparent, colorless Teflon.

The steps of the improved process and the objects and advantages thereof will appear from the following detailed description.

In this process the preparatory and coating operations are preferably, though not necessarily, accomplished on flat aluminum blanks after which the coated blanks are formed into the desired shape for the finished article. The steps are in the following sequence.

Two-stage power-spray wash and rinse The first wash is in a tWo stage spray washer, which removes all dirt and oils which might otherwise contaminate the grit supply of the blasting operation which is to follow. It has been found that a power-spray twostage wash coupled with a second step of clean rinsing by a fresh hot water hosing insures good adhesion of the Teflon coating and will prevent resistance to blistering during use of the articles for cooking purposes.

The first power spray is preferably with a standard mild alkaline cleaner solution, the spray nozzles being directed at the blanks at high velocity. A specific example of a commercially available mild alkaline spray concentrate is Wyandotte Companys Spray Altrex used in 160180 F. hot water. For the second stage, recirculated hot water is sprayed at high velocity in similar fashion at the face of the blanks, a constant make up and overflow being provided to reduce excessive contamination by cleaner.

Clean rinse and dry Immediately following the second power spray a fresh hot water supply is directed by hose nozzles to complete a final rinsing and the blanks are then air dried.

Other types of conventional washing and rinsing methods such as liquid solvent degreasing, vapor degreasing, or alkaline cleaner soaks have not been found to be dependable in imparting complete resistance to blistering when the other steps of the process are followed and accordingly the mild alkaline cleaner power spray wash as above described is preferred.

Grit blast The aluminum blanks after drying to eliminate uneven marking are next subjected to a grit blasting treatment. A standard commercial centrifugal thrower type of blasting machine is preferably used such as the Rotoblast Patented Mar. 29, 1966 Machine with rotating table as sold by the Pangborn Company. An angular grit of iron having hard, sharp edges is used. As is well known in the trade, this type of grit is made by crushing pieces of iron shot to impart hard, sharp angled surfaces. Conventionally it is used for preparing surfaces for galvanizing and like processes. As is also well known, angular grit comes in different standard size classifications and it has been found that a grit on the order of SAE size classification gives a roughened surface for excellent adhesion of the Teflon coating and without creating problems in obtaining a smooth outer surface of the Teflon coating. A larger size grit such as SAE #50 marks the surface to a greater degree and control of the coating to insure a smooth Teflon surface is diflicult, while a smaller grit such as SAE results in substantially less tenacious adhesion of the coating.

During grit blasting the supply of fresh grit must be regulated to maintain a level of 70-80% hard, sharp particles. To accomplish this, a standard air separator device may be used to remove smaller pieces of worn particles. Fresh grit is fed automatically into the machine supply to maintain the above percentage more or less constant.

As the blanks pass from the machine an air blast is then directed against them so as to remove most of the loose grit adhering to the blanks.

Second wash and clean rinse After the air blast the blanks are next passed through a second mild alkaline cleaner power spray treatment and rinse which is identical with the initial treatment outlined by the steps prior to grit blast. The blanks are thus cleaned and loose grit adhering to the blanks is further loosened.

Deoxidation cleaning As the blanks come from the second clean rinse some residual grit is still adhering to the surfaces. Such residual grit on the blanks at this stage causes them to be characterized by a greyish appearance. The deoxidation cleaning step next undertaken materially lightens and brightens the coloration of the aluminum surfaces.

The blanks are preferably soaked for a period of approximately eight minutes or more in a suitable aluminum deoxidizer solution such as the commercially available Wyandotte Company Cleaner #2487, the solution being made up by 14l8 ozs. deoxidation cleaner per gallon of water at room temperature. The deoxidizer contains acid sulfates, chromic acid, and other additive agents. After soaking the blanks may then be sponged to speed the de-oxidizing action and rinsed with a high velocity spray of hot water.

In this step all residual grit and dark scale of old oxide deposits are chemically attacked and removed. Re-oxidizing of the aluminum surfaces takes place almost instantaneously during the rinsing and thus a colorless oxide surface is re-formed on the metal. Longer soaking periods and harder sprays are equivalent to the preferred sponging and rinse but are more time consuming.

Drying and coating Following the deoxidation step, the blanks are preferably dried by any suitable method such as room drying so as to avoid dilution of the Teflon coating dispersion when it is applied.

The method of applying a coating to the aluminum metal surfaces may be any of the conventional methods such as flowing, spraying or brushing. However it is to be noted that in practising the present invention a transparent nearly colorless Teflon is used, Teflon #30 or #308 being the Du Pont Company designation of a clear pure Teflon. An aqueous dispersion is flow coated brightly finished article for cooking purposes.

with the blanks placed at an angle of about 25 from the vertical to allow suitable drainage. The coatingis then air dried and thus takes on a white appearance of the normal unsintered Teflon. A standard sintering operation is then performed in a suitable oven at a temperature of 700-725 F. By coating as described a smooth surfaced Teflon layer of transparent nature will adhere tenaciously to the aluminum blanks and result in a clear If increased thickness is desired, a second coating may be applied.

The result of the above described process is an unusually light color of the coated metal, the Teflon being colorless and almost entirely transparent. Insofar as is known the use of hard and sharp jagged grit of cast iron and a deoxidation cleaning step has not been heretofore suggested in the Teflon coating of aluminum blanks, the most conventional prior methods being the coating of blanks with a pigmented primer before the application of the Teflon. In the present method the deoxidizer chemically attacks and removes any residual iron grit and other dark metallic scale Without harming or etching the aluminum surfaces. The result is a clean colorless new oxide re-formation on the blank to preserve and maintain a bright aluminum finish beneath the transparent Teflon.

What is claimed as novel and desired to be obtained by Letters Patent of the United States is:

1. The method of coating aluminum metal surfaces with polytetrafluoroethylene which comprises the steps of washing the surfaces with a mild alkaline cleaner by means of a high velocity spray and completely rinsing and drying; grit blasting the surfaces with an angular grit of cast iron having hard, sharp, jagged edges, the grit size being on the order of SAE classification #80 while constantly replenishing the g it to maintain a seventy to eighty perwashing and rinsing steps; then soaking the surfaces in an aluminum deoxidation solution and spraying to remove residual grit and scale and thereby re-oxidize the surfaces with a clean, colorless oxide coating; then applying a coating of an aqueous dispersion of pure colorless polytetrafluoroethylene and drying and sintering the same.

2. In the method of preparing aluminum surfaces for coating with polytetrafluoroethylene which includes grit blasting said surfaces preceded and followed by mild alkaline solution spray cleaning and rinsing treatments, the improvement 'which consists in blasting the surfaces with an angular iron grit having hard, sharp edges and of a size on the order of SAE classification #80, and after said second cleaning and rinsing treatment, soaking the surfaces in an aluminum deoxidizing bath and thereafter thoroughly rinsing the same and re-oxidizing the metal surfaces to impact an appearance characterized by the bright and light aluminum coloration.

References Cited by the Examiner UNITED STATES PATENTS 2,404,816 7/ 1946 Snyder 117--49 2,562,117 7/1951 Osdal 117-132 2,647,079 7/1953 Burnham 117-49 2,817,562 12/1957 Fleming et a1 117132 X 2,883,331 4/1959 Halpert 1486.27 X 3,008,601 11/1961 Cahne 117132 X OTHER REFERENCES The Iron Age, June 4, 1959, p. 136, T5200 18.

RICHARD D. NEVIUS, Primary Examiner.

JOSEPH B. SPENCER, Examiner.

R. S. KENDALL, Assistant Examiner.

Claims (1)

1. THE METHOD OF COATING ALUMINUM METAL SURFACES WITH POLYTGETRAFLUOROETHYLENE WHICH COMPRISES THE STEPS OF WASHING THE SURFACES WITH A MILD ALKALINE CLEANER BY MEANS OF A HIGH VELOCITY SPRAY AND COMPLETELY RINSING AND DRYING GRIT BLASTING THE SURFACES WITH AN ANGULAR GRIT OF CAST IRON HAVING HARD, SHARP, JAGGED EDGES, THE GRIT SIZE BEING ON THE ORDER OF SAE CLASSIFICATION #80 WHILE CONSTANTLY REPLENISHING THE GRIT TO MAINTAIN A SEVENTY TO EIGHTY PERCENT SHARP GRIT CONTENT; AIR BLASTING AND REPEATING THE FIRST WASHING AND RINSING STEPS; THEN SOAKING THE SURFACES IN AN ALUMINUM DEOXIDATION SOLUTION AND SPRAYING TO REMOVE RESIDUAL GRITAND SCALE AND THERBY RE-OXIDIZE THE SURFACES WITH A CLEAN, COLORLESS OXIDE COATING; THEN APPLYING A COATING OF AN AQUEOUS DISPERSION OF PURE COLORLESS POLYTETRAFLUOROETHYLENE AND DRYING AND SINTERING THE SAME.
US23512662 1962-11-02 1962-11-02 Method of teflon coating of metals Expired - Lifetime US3243321A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US23512662 US3243321A (en) 1962-11-02 1962-11-02 Method of teflon coating of metals

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US23512662 US3243321A (en) 1962-11-02 1962-11-02 Method of teflon coating of metals

Publications (1)

Publication Number Publication Date
US3243321A true US3243321A (en) 1966-03-29

Family

ID=22884201

Family Applications (1)

Application Number Title Priority Date Filing Date
US23512662 Expired - Lifetime US3243321A (en) 1962-11-02 1962-11-02 Method of teflon coating of metals

Country Status (1)

Country Link
US (1) US3243321A (en)

Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3489589A (en) * 1966-10-14 1970-01-13 Gillette Co Razor blade coating method and apparatus
US3511690A (en) * 1967-06-05 1970-05-12 Nat Presto Ind Production of polytetrafluoroethylene-containing coatings on metallic bases
US3900658A (en) * 1970-02-21 1975-08-19 Daikin Ind Ltd Polyfluorocarbon article and method for making the same
US5067912A (en) * 1987-11-03 1991-11-26 M/A-Com Adams-Russell, Inc. Subassembly for a microwave connector and method for making it
US5097109A (en) * 1990-02-20 1992-03-17 General Motors Corporation Insulated aluminum weld fixture and a method of making same
US5213739A (en) * 1991-06-26 1993-05-25 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Process for bonding elastomers to metals
US5338572A (en) * 1991-07-04 1994-08-16 Alluflon- S.P.A. Industrial procedure for the application of a P.T.F.E. film on aluminum surfaces
US6511479B2 (en) * 2000-02-28 2003-01-28 Conmed Corporation Electrosurgical blade having directly adhered uniform coating of silicone release material and method of manufacturing same
US20050254031A1 (en) * 2003-06-27 2005-11-17 Asml Holding N.V. Immersion photolithography system and method using inverted wafer-projection optics interface
US20070064209A1 (en) * 2003-04-07 2007-03-22 Nikon Corporation Exposure apparatus and method for manufacturing device
DE102007040096A1 (en) * 2007-08-24 2009-04-16 Elringklinger Ag component
US20090207397A1 (en) * 2003-11-14 2009-08-20 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
DE102009054532A1 (en) 2008-12-22 2010-07-01 Basf Se Continuous preparation of polymer particles of water-soluble polymers in tube rector comprises producing a dispersion of liquid dispersed phase of monomers in e.g. liquid continuous phase and polymerizing monomers using radical initiators
US7761970B1 (en) 2007-01-23 2010-07-27 Marchese Sr Justin W Method of manufacturing of electrosurgical implements
WO2011026876A1 (en) 2009-09-04 2011-03-10 Basf Se Water-absorbent polymer particles
WO2011113728A1 (en) 2010-03-15 2011-09-22 Basf Se A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution
USRE42741E1 (en) 2003-06-27 2011-09-27 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
WO2011117263A1 (en) 2010-03-24 2011-09-29 Basf Se A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution
WO2011117215A1 (en) 2010-03-24 2011-09-29 Basf Se Method for removing residual monomers from water-absorbent polymer particles
WO2011117187A1 (en) 2010-03-24 2011-09-29 Basf Se Ultrathin fluid-absorbent cores
WO2013045163A1 (en) 2011-08-12 2013-04-04 Basf Se A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution
WO2014079694A1 (en) 2012-11-21 2014-05-30 Basf Se A process for producing surface-postcrosslinked water-absorbent polymer particles
WO2014118025A1 (en) 2013-01-30 2014-08-07 Basf Se Method for removal of residual monomers from water-absorbing polymer particles
WO2015028158A1 (en) 2013-08-26 2015-03-05 Basf Se Fluid-absorbent article
DE102017205365A1 (en) 2016-03-30 2017-10-05 Basf Se liquid-absorbing article
DE102017205367A1 (en) 2016-03-30 2017-10-05 Basf Se Flüssigkeitabsorbierender Article
DE102017205368A1 (en) 2016-03-30 2017-10-05 Basf Se Ultrathin flüssigkeitabsorbierender Article
WO2018141677A1 (en) 2017-02-06 2018-08-09 Basf Se Fluid-absorbent article
WO2018149783A1 (en) 2017-02-17 2018-08-23 Basf Se Fluid-absorbent article

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2404816A (en) * 1945-01-08 1946-07-30 Thompson Prod Inc Seal surface
US2562117A (en) * 1949-07-08 1951-07-24 Du Pont Polytetrafluoroethylene coating compositions
US2647079A (en) * 1948-06-03 1953-07-28 Sprague Electric Co Production of insulated condenser electrodes
US2817562A (en) * 1953-07-01 1957-12-24 Gen Motors Corp Coated piston
US2883331A (en) * 1956-07-23 1959-04-21 Robert O Bolt Inhibited reactor coolants and use thereof
US3008601A (en) * 1954-12-13 1961-11-14 Collette Gregoire Polytetrafluoroethylene coated cooking utensils

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2404816A (en) * 1945-01-08 1946-07-30 Thompson Prod Inc Seal surface
US2647079A (en) * 1948-06-03 1953-07-28 Sprague Electric Co Production of insulated condenser electrodes
US2562117A (en) * 1949-07-08 1951-07-24 Du Pont Polytetrafluoroethylene coating compositions
US2817562A (en) * 1953-07-01 1957-12-24 Gen Motors Corp Coated piston
US3008601A (en) * 1954-12-13 1961-11-14 Collette Gregoire Polytetrafluoroethylene coated cooking utensils
US2883331A (en) * 1956-07-23 1959-04-21 Robert O Bolt Inhibited reactor coolants and use thereof

Cited By (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3489589A (en) * 1966-10-14 1970-01-13 Gillette Co Razor blade coating method and apparatus
US3511690A (en) * 1967-06-05 1970-05-12 Nat Presto Ind Production of polytetrafluoroethylene-containing coatings on metallic bases
US3900658A (en) * 1970-02-21 1975-08-19 Daikin Ind Ltd Polyfluorocarbon article and method for making the same
US5067912A (en) * 1987-11-03 1991-11-26 M/A-Com Adams-Russell, Inc. Subassembly for a microwave connector and method for making it
US5097109A (en) * 1990-02-20 1992-03-17 General Motors Corporation Insulated aluminum weld fixture and a method of making same
US5213739A (en) * 1991-06-26 1993-05-25 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Process for bonding elastomers to metals
US5338572A (en) * 1991-07-04 1994-08-16 Alluflon- S.P.A. Industrial procedure for the application of a P.T.F.E. film on aluminum surfaces
US6511479B2 (en) * 2000-02-28 2003-01-28 Conmed Corporation Electrosurgical blade having directly adhered uniform coating of silicone release material and method of manufacturing same
US8537331B2 (en) 2003-04-07 2013-09-17 Nikon Corporation Exposure apparatus and method for manufacturing device
US20070064209A1 (en) * 2003-04-07 2007-03-22 Nikon Corporation Exposure apparatus and method for manufacturing device
US20080291410A1 (en) * 2003-04-07 2008-11-27 Nikon Corporation Exposure apparatus and method for manufacturing device
US8111375B2 (en) 2003-04-07 2012-02-07 Nikon Corporation Exposure apparatus and method for manufacturing device
USRE42741E1 (en) 2003-06-27 2011-09-27 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US20050254031A1 (en) * 2003-06-27 2005-11-17 Asml Holding N.V. Immersion photolithography system and method using inverted wafer-projection optics interface
US7898643B2 (en) * 2003-06-27 2011-03-01 Asml Holding N.V. Immersion photolithography system and method using inverted wafer-projection optics interface
US20110122380A1 (en) * 2003-06-27 2011-05-26 Asml Holding N.V. Immersion photolithography system and method using inverted wafer-projection optics interface
US20090207397A1 (en) * 2003-11-14 2009-08-20 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US8547519B2 (en) 2003-11-14 2013-10-01 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US8634056B2 (en) 2003-11-14 2014-01-21 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US10345712B2 (en) 2003-11-14 2019-07-09 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US9134622B2 (en) 2003-11-14 2015-09-15 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US9952515B2 (en) 2003-11-14 2018-04-24 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US9134623B2 (en) 2003-11-14 2015-09-15 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
US7761970B1 (en) 2007-01-23 2010-07-27 Marchese Sr Justin W Method of manufacturing of electrosurgical implements
DE102007040096A1 (en) * 2007-08-24 2009-04-16 Elringklinger Ag component
DE102007040096B4 (en) * 2007-08-24 2016-05-12 Elringklinger Ag Component and methods for making
DE102009054532A1 (en) 2008-12-22 2010-07-01 Basf Se Continuous preparation of polymer particles of water-soluble polymers in tube rector comprises producing a dispersion of liquid dispersed phase of monomers in e.g. liquid continuous phase and polymerizing monomers using radical initiators
WO2011026876A1 (en) 2009-09-04 2011-03-10 Basf Se Water-absorbent polymer particles
WO2011113728A1 (en) 2010-03-15 2011-09-22 Basf Se A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution
WO2011117187A1 (en) 2010-03-24 2011-09-29 Basf Se Ultrathin fluid-absorbent cores
WO2011117263A1 (en) 2010-03-24 2011-09-29 Basf Se A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution
WO2011117215A1 (en) 2010-03-24 2011-09-29 Basf Se Method for removing residual monomers from water-absorbent polymer particles
WO2013045163A1 (en) 2011-08-12 2013-04-04 Basf Se A process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution
EP3381956A1 (en) 2012-11-21 2018-10-03 Basf Se Surface-postcrosslinked water-absorbent polymer particles
WO2014079694A1 (en) 2012-11-21 2014-05-30 Basf Se A process for producing surface-postcrosslinked water-absorbent polymer particles
WO2014118025A1 (en) 2013-01-30 2014-08-07 Basf Se Method for removal of residual monomers from water-absorbing polymer particles
WO2015028158A1 (en) 2013-08-26 2015-03-05 Basf Se Fluid-absorbent article
DE102017205365A1 (en) 2016-03-30 2017-10-05 Basf Se liquid-absorbing article
DE102017205368A1 (en) 2016-03-30 2017-10-05 Basf Se Ultrathin flüssigkeitabsorbierender Article
DE102017205367A1 (en) 2016-03-30 2017-10-05 Basf Se Flüssigkeitabsorbierender Article
WO2018141677A1 (en) 2017-02-06 2018-08-09 Basf Se Fluid-absorbent article
WO2018149783A1 (en) 2017-02-17 2018-08-23 Basf Se Fluid-absorbent article

Similar Documents

Publication Publication Date Title
US5705082A (en) Roughening of metal surfaces
US4552784A (en) Method of coating a substrate with a rapidly solidified metal
CA1120251A (en) Corrosion inhibiting hafnium compositions
US2403426A (en) Metal coating process
US2279686A (en) Method and apparatus for cleaning and painting
US4707191A (en) Pickling process for heat-resistant alloy articles
KR930006494B1 (en) Method for descaling hot-rolled stainless steel strip
US2032174A (en) Process for cleaning metal surfaces
FR2508481A1 (en) Fluoride-free concentrates and solutions and processes for low-temperature cleaning of aluminum
US2970065A (en) Forming an aluminum-containing alloy protective layer on metals
CN1222585A (en) Metal surface treating method
US3524245A (en) Continuous tube forming and metallizing process
US3125471A (en) Commercially available sheet finishes
US2390007A (en) Apparatus for continuously hot dip coating of tin on coiled strip
FR2743742A1 (en) Process for treating a metal surface and manufacturing a culinary article
US3188776A (en) Surface treatment of steel
GB2157608A (en) Weld spatter protective coating
US5766684A (en) Stainless steel acid treatment
US3480461A (en) Metal articles having polytetrafluoroethylene-coated pressing surfaces and methods of their manufacture
US4496404A (en) Composition and process for treatment of ferrous substrates
US2301983A (en) Coated ferrous article and method of making
US2438013A (en) Treated steel sheet and process
US3210843A (en) Method of influencing the surface profile of solid elements, more especially of surface-improved or plated metal strips or sheets
US2544139A (en) Process for enameling aluminumrich alloys
US2516986A (en) Stainless steel finish