Classifications

• • C—CHEMISTRY; METALLURGY
  • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
  • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
  • C23C26/00—Coating not provided for in groups C23C2/00 - C23C24/00
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41N—PRINTING PLATES OR FOILS; MATERIALS FOR SURFACES USED IN PRINTING MACHINES FOR PRINTING, INKING, DAMPING, OR THE LIKE; PREPARING SUCH SURFACES FOR USE AND CONSERVING THEM
  • B41N3/00—Preparing for use and conserving printing surfaces
  • B41N3/03—Chemical or electrical pretreatment

Definitions

• this surface layer consists of an oxide layer and / or a mixed oxide layer and / or an oxide hydrate layer and / or an oxide hydroxide layer and / or an oxide hydroxide hydrate layer and / or an oxygen-containing metal complex compound layer.
• This protective layer is initially only a few angstroms thick; it increases to 45 to 90 angstroms over the course of a month and then remains almost unchanged.
• the surface of iron consists of mixed iron oxides, namely trivalent iron in equivalents of oxygen, hydrogen and iron that cannot be clearly defined.
• the surface of iron can - as - practical tests show - in contrast to the surface of aluminum, tin and chrome mechanically with a relatively soft friction partner, e.g. Paper, do not separate layers. Layer separation is to be understood as the oxidic layer that can be mechanically transferred to the friction partner.
• the surface of tinned iron sheet consists of the following layers: Mixture of tin (IV) oxide layer and tin (II) oxide layer, tin layer, tin-iron alloy layer and finally the lowest iron layer.
• tin-plated iron sheets are known as tinplate, which is normally found on passivated and greased on the surface.
• the passivation layer e.g. chrome layer
• the amount of tin is standardized eg according to Euronorm 77-65 with E1 to E4 or according to ASTM A624 from Desig nation No. 10 to No. 135/25. Information on the type of chemical surface treatments used and the amount of, for example, chromium in the passivation layer are also contained in ASTM A 624. According to this, the amount of chromium in chemical passivation (Chromc Acid-Treated Tin-Plate) is not more than 250 ⁇ g chromium / ft 2 surface, while in electro-chemical passivation (Cathodic-Sodium Dichromate-Treated Tin Plate) it is about 500 ⁇ g Chromium / ft 2 .
• the tinplate is usually greased.
• Common greasing agents are e.g. Dioctyl sebacate (DOS), cottonseed oil and butyl stearate (ATBC). Normally the circulation is approx. 0.10 g / base box to 0.40 g / base box according to ASTM A 624.
• the surface of electrolytically chrome-plated iron sheets (ultrafine sheet) consists of a chrome (III) oxide layer and a metallic chrome layer.
• the metallic chromium layer layer is between 3 and 13 mg chromium / ft 2 surface and the overlying chromium oxide layer contains 0.3 to 0.4 mg chromium / ft 2 surface.
• the surface of the electrolytically chrome-plated thin sheet is also greased, as is the case with the tinplate mentioned above the case is.
• this hydrophilization is achieved by producing a hydroxide of the metal in question or a hydroxide-containing compound of the metal on these metal surfaces and / or metal oxide surfaces. According to a preferred embodiment of the present invention, a hydroxide of the lowest valence level of the metal is produced on the surfaces.
• the metal surfaces thus hydrophilized in accordance with the invention have technologically highly interesting unexpected properties, in particular it is possible, besides the mechanical processes molding processes such as deep drawing or drawing without using the lubricants previously considered indispensable to achieve a much more effective and at the same time leaps and bounds more economical painting.
• the aluminum sheet which has been made hydrophilic as described above can be recognized as hydrophilic in that even when the sheet is positioned vertically in relation to our site, water poured on completely wets the mechanically treated aluminum surface as described above and shows a dwell time of 60 seconds, after which time one of Evaporation of the water progresses from top to bottom, or no offset color is accepted.
• This offset ink example is also used for this show that the surface reactions, which lead to the contrary properties such as hydrophilic hydrophobic, have not yet been sufficiently scientifically researched.
• the metal hydroxide level of the lowest valency disclosed according to the invention is somewhat clearer by the offset printing ink example: if a hydroxide of the known valence level were present, this could be rinsed off or, if not dissociated, it could be removed from the surface by rubbing with the moist printing ink.
• noble copper
• base metal Cr, Fe, Al, Su
• Copper always takes on color, as do the oxides of base metals, which have a hydrophobic effect; the hydroxides of the base metals are hydrophilic until they become hydrophobic again through gradual oxidation.
• Newly added water is again accepted from the surface, i.e. the surface remains hydrophilic - as tests have shown - for about 24 hours. After 24 hours, the metal surface gradually becomes hydrophobic again.
• Example 1 An aluminum sheet of the type mentioned in Example 1 is thereby hydrophilized chemically by immersing it in an sodium hydroxide solution for 30 minutes; the temperature of the caustic soda is 60 to 80 ° C. Then the aluminum sheet is pulled out of the caustic soda bath and rinsed with distilled water until no more alkalinity can be found in the rinsing water. Then, as described in Example 1, the hydrophilization test is carried out by observing the running speed in the vertical position of the sheet. The experiments show that the hydrophilization in the chemical manner described in this example has the same degree as the mechanical hydrophilization described in Example 1.
• An aluminum sheet of the type mentioned in Example 1 is immersed in an electrolyte which consists of a 0.5% sodium hydroxide solution at room temperature (25 ° C.).
• An anodic current of 70 Amp / m 2 is applied (based on the surface of the aluminum). After only 2 seconds, the entire aluminum sheet is of the same hydrophilic nature as the sheet treated according to Examples 1 and 2. The sheet is also cleaned here by rinsing with distilled water until the drained distilled water is alkali-free. The method of determining the hydrophilicity is also the same as in the aforementioned examples.
• Example 1 The aluminum sheet of the type mentioned in Example 1 is placed in a 200 0 0 heated electric furnace and left there for 6 minutes. The sheet is then removed from the electric furnace and allowed to cool to room temperature in a normal laboratory atmosphere. The test for the hydrophilicity achieved, which is shown in detail in Example 1, was then carried out; Here, too, the experiment showed that the sheet thermally treated in this way had the same degree of hydrophilicity as the sheets shown in Examples 1 to 3. In the present case, an even longer lasting hydrophilicity is achieved; it amounts to for at least 36 hours.
• a tinplate of the DIN A4 format is subjected to the hydrophilization process shown in Examples 1 to 4.
• a A4 tinplate is immersed in the NaOH electrolyte as above and then one. Second as anode, then one second as cathode, then another second as an anode, then another second as cathode. The current density was again 70 amp / m 2 tinplate.
• the tinplate was removed from the bath and rinsed with distilled water until the rinsed water was no longer alkaline.
• the hydrophilicity achieved was then measured by carrying out the hydrophilicity test already described in detail above in the vertical position of the sheet.
• a chrome-plated iron sheet of the DIN A 4 format was treated mechanically with a pressure of 5 kg / cm 2 by means of a fine polishing disc (based on plastic fabric) by moving the fine polishing disc up and down 5 times.
• the surface of the chromed iron sheet of the DIN A4 format is treated chemically by rubbing a mixture of 10% gelatin and 2% glycerine and 88% water on the surface by means of dilute sulfuric acid or the sheet immersed in the solution just described for 5 seconds. Instead of immersing, the surface of the chromed iron sheet can be subjected to 5 rubbing movements using a chemically inert fleece.
• a chromed iron sheet of the DIN A4 format is thermally treated for 6 minutes in an electric furnace with an internal temperature of 200 ° C. and then removed from this furnace. After cooling to room temperature, the chrome-plated iron sheet thus thermally treated had a hydrophilicity for a period of 100 hours.
• This preservation is achieved by applying a coating of a chemical compound on the surface as soon as possible after the hydrophilization process has ended is both water soluble and soluble in organic solvents; preferred coating formers are the glycols, amines, alkanolamines, as well as gelatin and gelatin-like substances.
• Gum arabic, iso-paraffins or polyparaffins in solution and / or in emulsion are suitable as further coating agents.
• These coating agents desirably effect the exclusion or prevention of the access of atmospheric oxygen and / or atmospheric moisture to the hydrophilic metal surface or metal oxide surface.
• the aluminum sheet made hydrophilic according to Example 1 is preserved immediately after the end of the hydrophilization treatment by applying tetraethylene glycol to the surface. for example by spraying; alternatively, the preservation can also be effected by passing the hydrophilized metal sheet through a bath of tetraethylene glycol immediately after the hydrophilization.
• esters of montanic acid with ethanediol and / or 1,3-butanediol include esters of montanic acid with ethanediol and / or 1,3-butanediol, glycerol monoacetate, polyethylene glycol, copolymer of esters of acrylic acid with monohydric aliphatic alcohols C 1 -C 4, mixture of alkylphenol polyglycol ether with 20 ethylene oxide groups, alkylphenol polyglycol ether-Formaldehydacetat and C 12 -C 18 Fatty alcohol-polyethylene glycol-polypropylene glycol ether, polyvinyl acetate from aliphatic saturated aldehydes C1-C6 with a molecular weight of more than 1,000, dibutyl sebacate, acetyltributyl citrate, acetyl-tri-2-ethylhexyl citrate, diphenyl-2-ethyl-
• the duration of the preservation depends on the intensity and time of the preservation treatment; at least the duration of the conservation is over sufficient to ensure the further processing stages of the hydrophilized surfaces while maintaining the hydrophilic character.
• the present invention is further based on the surprising finding that the hydrophilization of the metal surfaces or the metal oxide surfaces is achieved by creating hydroxyl-containing compounds on the surface.
• the formation energy of the oxide of divalent iron is substantially lower than the formation energy of the hydroxide of divalent iron; on the other hand, the energy of formation of the hydroxide of trivalent iron is in turn significantly greater than that of the hydroxide of divalent iron. After all, the formation energy of the ferro-ferric oxide is greatest.
• the distance between the formation energy of the hydroxide is trivalent Aluminum and oxides of trivalent aluminum are relatively low. It is 304 to 390 kcal / mol, but with 86 kcal / mol the residual energy is so great that the hydroxide stability is lower relative to that of tin, iron and chromium.
• the formation energy of the hydroxide of trivalent chromium is 245 kcal / mol, in contrast the formation energy of the oxide of trivalent chromium is 267 kcal / mol. It is therefore only about that of the hydroxide, which in turn can be used to derive the great stability and duration of the hydrophilic stage in chromed sheet metal.
• a chemical proof of the presence of hydroxyl-containing metal compounds on the surfaces of the hydrophilized metals is the fact that condensation with hydroxyl-containing organic substances such as e.g. Salicylic aldehyde takes place.
• the aluminum sheet which has been hydrophilized and preserved analogously to one of the processes mentioned in the examples, is immediately immersed in an inert solution consisting of isopropanol and 0.5% triethanolamine in order to renew the preservation effect.
• a person skilled in the art can measure that the working heat must be dissipated by means of deep-frozen external or internal media, if water is to be consumed, in order to ensure continuous production.
• the increase in the length of the can clearly indicates the cooling of the stamp, since the reduced distances between the ring and the stamp were caused by the thermal expansion of the stamp.
• Cans with a wall thickness of less than 0.06 mm are not standard in order to be able to be carried out easily through the next work steps.
• the water hydrophilicity test is positive, that is the hydrophillized surface has been kept upright or, based on the end surface, has reproduced by 50% analogously to the hydrophilicity examples by means of mechanical friction energy.
• the metal surface is homogeneous, hydrophilic in all can areas and, unlike the can produced as standard, no longer needs to be made hydrophilic in an alkaline cleaning bath.
• hydrophilization can be made simpler and more controllable in terms of process technology if it is carried out on a belt, that is to say before forming, instead of individual pieces which are contaminated with lubricants in the complex surface area of the can bottom contour.
• the usual lubricants include: aqueous 3-20% oil emulsions, effecting a pH correction of e.g.
• Rust inhibitors are also added; synthetic lubricants such as polyglycols are also used.
• roller coating is to be carried out for an external coating
• spray coating and the powder coating is preferably to be used for an internal coating.
• Dip painting is usually carried out with simultaneous interior and exterior painting.
• Another method is to use aqueous alkalis to remove the lubricants due to saponification.
• metal surfaces hydrophilized according to the invention can optionally be stabilized by substances which are soluble in water as well as in organic solvents, for example glycols.
• the stabilizing agents such. B. the glycose and the amines themselves components of the paint.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Shaping Metal By Deep-Drawing, Or The Like (AREA)
• Chemical Treatment Of Metals (AREA)
• Laminated Bodies (AREA)
• Other Surface Treatments For Metallic Materials (AREA)
• Oxygen, Ozone, And Oxides In General (AREA)

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• 1978
  • 1978-12-20 DE DE19782855170 patent/DE2855170A1/de not_active Ceased
• 1979
  • 1979-09-20 US US06/077,437 patent/US4292095A/en not_active Expired - Lifetime
  • 1979-11-22 CA CA000340413A patent/CA1137392A/fr not_active Expired
  • 1979-12-10 AT AT79105037T patent/ATE3066T1/de not_active IP Right Cessation
  • 1979-12-10 EP EP79105037A patent/EP0012905B1/fr not_active Expired
  • 1979-12-17 NL NL7909080A patent/NL7909080A/nl not_active Application Discontinuation
  • 1979-12-19 DK DK542479A patent/DK542479A/da not_active Application Discontinuation
  • 1979-12-19 BE BE1/9653A patent/BE880712A/nl not_active IP Right Cessation
  • 1979-12-20 ES ES487120A patent/ES487120A1/es not_active Expired

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