Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
  • B05D7/14—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to metal, e.g. car bodies

Definitions

• the invention relates to a method for decorating and corrosion-preventing painting of metallic can bodies, preferably made of tin-plated sheet metal, in particular sealed can bodies on the bottom side, in which a decorative print is first applied to the outer surface of the can body and hardened by drying and / or crosslinking before the application of the corrosion-preventing paint.
• the invention has for its object to develop a method of the type described in the introduction so that a reliable corrosion-preventing coating of the entire surface of the can body is achieved with a simultaneous reduction in the process steps and a reduction in equipment and personnel, while at the same time saving paint material.
• the method mentioned in the introduction is characterized in that the can body, which is provided with a decorative print, is subjected to an electro-dip coating with subsequent drying and / or crosslinking of the dip lacquer in order to apply the anti-corrosion lacquer.
• Electrocoating is known for coating metallic hollow bodies, in particular in the automotive industry, and has also been described in connection with the application of a coating to can bodies (DE-OS 20 24 106).
• the application of the corrosion-preventing lacquer is provided by immersing the can bodies of three-part cans after the completion of the can bodies before the bodies are provided with a bottom and filled.
• the question of a decorative print is not addressed in the previous publication. If such a decorative print were to be provided, it would have to be applied to the corrosion-preventing lacquer layer, which would cause considerable difficulties, which are in particular a risk of damage to the corrosion-preventing lacquer layer, which cannot be avoided by the mechanical stress on the can body during the printing process.
• the possibility of electrocoating can bodies in the process for decorating and corrosion-preventing painting of such can bodies without affecting the development of the The method described in the introduction has remained, although the electro-dip coating in the combination described with the decorative printing leads to very considerable advantages.
• the electrodeposition coating provides a safe coating of all surfaces not yet protected against corrosion in a single operation, and possible defects in the surfaces already provided with previously applied lacquer are also protected against corrosion by appropriate deposition of the lacquer in the immersion coating.
• the deposition of the paint in the electrocoating process takes place at all points on the surface of the can body only in an extremely small layer thickness, which is also reinforced at the edges and curves with a small radius of curvature, so that due to the increased risk of corrosion there is a correspondingly improved protection by Paint application is achieved.
• the application of the base coat on the outer surface which is otherwise necessary, can be dispensed with.
• This basic lacquer application has so far been necessary because surfaces of the decorative print which are set off from one another in color cannot be printed directly next to one another, but instead have to enclose a distance between them because of the risk of the printing inks developing.
• the basic lacquer application forms the surface coating of the can body between the color fields of the decor print and at the same time complements the overall decor with its coloring.
• the decorative print insofar as it consists of separate color fields, is applied to the bare metallic outer surface and hardened, and a corrosion-preventing lacquer is applied to the can body provided with this decorative print Apply electro-dip coating and at the same time thereby supplement or complete the decorative print.
• the optical addition is possible with both pigmented and non-pigmented lacquer.
• the pigmentation of the corrosion-preventing lacquer can be carried out with color pigments that were also included in the base coat application in the conventional process.
• the areas remaining between the separate color fields of the decor print are provided with a colored varnish coating which corresponds to the base coat and thus complements or completes the decor print. Since the electrodeposition coating determines the paint dependence on the electrical conductivity between the can body and the counterelectrode and the paint layer represents an insulation resistance, it is ensured despite the sharp delimitation of the paint job by the electrodeposition coating and the decorative print that no areas remain between these two paint applications that are not adequately covered with a layer of lacquer and form areas at risk of corrosion.
• the color areas mentioned, separated from one another by the decorative printing can be pictorial representations, letters, numbers and the like.
• the individual, separated color areas can also be applied in the context of a multicolor print.
• an electrically conductive lacquer is used for the decor printing of all the colored surfaces and that the entire surface of the can body is subsequently completely coated with a clear lacquer by means of the electrocoating.
• the aforementioned method is particularly useful for the production of decorated cans, the outer surfaces of which are exposed to severe stress during the subsequent treatment. This is because the varnish applied to the decorative print creates a protective layer for this decorative print and at the same time achieves a corrosion-preventing coating on the surfaces not coated by the decorative print in a single operation.
• the aforementioned method is particularly recommended in cases where the outer surface of the can body adjacent to the decorative print even bright surfaces having b z w. the separated color fields of the decor print are separated from each other by blank areas.
• the decorative print is applied to the bare can bodies in a manner similar to the method described above, and after this decorative print has hardened, the electrocoating is carried out with a clear varnish.
• the electrical conductivity of the varnish used for the decor printing can be adjusted so that the thickness of the varnish layer that arises on the color fields of the decor printing during electrodeposition coating is kept smaller than in the other areas.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Wood Science & Technology (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Details Of Rigid Or Semi-Rigid Containers (AREA)
• Preventing Corrosion Or Incrustation Of Metals (AREA)
• Electroplating Methods And Accessories (AREA)
• Physical Vapour Deposition (AREA)
• Printing Methods (AREA)
• Adornments (AREA)
• Table Devices Or Equipment (AREA)
• Manufacturing Of Printed Wiring (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (3)

Family

ID=6240305

Family Applications (1)

Country Status (9)

Cited By (1)

Families Citing this family (7)

Family Cites Families (17)

• 1984
  • 1984-07-11 DE DE19843425435 patent/DE3425435A1/de active Granted
• 1985
  • 1985-06-25 AT AT85107862T patent/ATE40802T1/de not_active IP Right Cessation
  • 1985-06-25 EP EP85107862A patent/EP0167923B1/fr not_active Expired
  • 1985-06-25 DE DE8585107862T patent/DE3568261D1/de not_active Expired
  • 1985-06-28 CA CA000485992A patent/CA1270792A/fr not_active Expired - Lifetime
  • 1985-07-09 GR GR851698A patent/GR851698B/el unknown
  • 1985-07-09 US US06/753,317 patent/US4693801A/en not_active Expired - Lifetime
  • 1985-07-09 DD DD85278413A patent/DD235426A5/de not_active IP Right Cessation
  • 1985-07-10 DK DK315185A patent/DK165393C/da not_active IP Right Cessation
  • 1985-07-11 ES ES545074A patent/ES8607064A1/es not_active Expired

Also Published As

Similar Documents

Legal Events