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
  • B05D5/00—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
  • B05D5/06—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures to obtain multicolour or other optical effects
  • B05D5/067—Metallic effect
  • B05D5/068—Metallic effect achieved by multilayers
• • 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
  • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
  • C23C18/16—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by reduction or substitution, e.g. electroless plating
  • C23C18/31—Coating with metals
  • C23C18/42—Coating with noble metals
  • C23C18/44—Coating with noble metals using reducing agents

Definitions

• the present invention concerns a process for metal painting or spraying of articles.
• stage components or furnishings of shows and exhibitions can advantageously be made of plastics or wood due their low cost, light weight and easiness of transport features - which features are quite relevant for use in stage settings - or due to their better workability in comparison to metals, which is quite convenient in making industrial patterns.
• foamed plastic or plastic foam
• a metal painting process comprises forming a thin film of metal silver similar to that used in mirror manufacturing, where an ammoniacal solution of silver nitrate is reduced with a solution of formic aldehyde or another organic reducer such as glucose, to obtain a thin reflecting film of metal silver imparting to the object a desired appearance.
• a process for metal coating metal, wood or plastics articles, even articles of large size and with complex shape, in order to impart them a metallic appearance comprises the following steps, in the specified order:
• the primer layer is applied to obtain a surface that is more suitable to allow a strong grip of the metalizing layer to the article.
• the resins used in the primer layer must be adapted to be firmly adhered to the materials forming the article and capable of covering the porous surface of the article to form a smooth and even surface over which a uniform metallic layer can be coated.
• step "a" The disclosed process is not completely satisfactory since the types of alkyd resins to be directly applied over the article in step "a" are limited by the compatibility of the solvents and diluents conveying the resins with the materials over which they are applied.
• a first object of the present invention is therefore to solve the problem of firmly anchoring the primer layer through a process that is devoid of the above mentioned drawbacks of the prior art.
• a second object of the present invention is to achieve a much improved adherence between the protection layer and the metalizing film by providing a transparent protection layer that is highly resistant to the action of chemical agents to scratches and to wear.
• the process of the invention allows to obtain a metalization of articles formed of metall, wood, plastics, foamed resins, plaster, concrete, glass, etc.
• the first step of the process provides for applying a layer of a preparative paint over the article surface, said paint being adapted to improve the grip of the primer resin that will be applied to the article in the next step.
• the step of deposing such preparative layer is followed by the application of a primer layer of a gripping alkyd resin of a type compatible with the paint employed in the previous step of preparing the article.
• Such step of applying a primer layer is followed by a step in which such primer layer is dried in a drying oven for 1 hour at a temperature of 50°C or alternatively in air for a time interval comprised between 12 and 24 hours.
• a silver mirror is formed over the article to impart a metal appearance to this latter, through a chemical reaction used in qualitative analytical chemistry for detecting aldehydes or aldoses and known as "Tollens test".
• the so obtained metalized article is then subjected to a washing step that in turn is followed by a step in which a layer of protecting resin formed by a water soluble polyurethane resin is applied to the article surface.
• the article is finished by being subjected to a drying step in an oven for 1 hour at a temperature of 50°C or alternatively in air for a time interval comprised between 12 and 24 hours.
• an article that has been metalized through the above disclosed process is subjected to a further step of forming a protection layer by applying a transparent acrylic resin that is soluble in an organic solvent.
• the metalized article will be more resistant to the action of chemical agents and will remain glossy for a long time without exhibiting yellowing phoenomena.
• this layer of transparent acrylic resin that is soluble in an organic solvent is applied over the existing layer formed by the polyurethane resin soluble in water, it does not cause problems of peeling and yellowing as it might happen in the articles obtained through a process in accordance with EP-A-0-346 954.
• the article After the step of applying the second protection layer the article is subjected to a drying step.
• An article obtained through the process of the invention has a uniformely metalized surface that is moreover resistant to the chemical agents and does not show yellowing phoenomena of the protection layer as time goes by.
• a layer of a transparent protective resin formed by a two-components acrylic-urethane resin is then applied over the metalized article.
• Such two-components acrylic-urethane resin imparts to the article a very high resistance against chemical agents.
• the article obtained in accordance with this embodiment of the process has very good properties of resistance to the chemical agents, to scratches and wear.

Landscapes

• Chemical & Material Sciences (AREA)
• General 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)
• Laminated Bodies (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=4222272

Family Applications (1)

Country Status (2)

Cited By (7)

Family Cites Families (10)

• 1997
  • 1997-08-20 CH CH194597A patent/CH692135A5/it not_active IP Right Cessation
• 1998
  • 1998-08-05 EP EP98114713A patent/EP0897759A3/fr not_active Withdrawn

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