JPS6328473A - Rust preventive method for edge part or the like - Google Patents

Abstract

PURPOSE:To improve the rust preventiveness of an edge part or the like where the formation of a coated film is difficult by coating a zinc-contg. high-viscosity rust preventive primer to said part after a chemical conversion treatment, then subjecting said part to electrodeposition painting. CONSTITUTION:The zinc-contg. high-viscosity paint 12 which is suppressed in the flowability at the time of paint baking is coated over the entire part of a vehicle body constituting member 10 including the edge part 11 and the like of an automobile subjected to the chemical conversion treatment in order to make provide rust prevention to the edge part, spot part, weld zone, etc. The member 10 of the automobile is then subjected to the electrodeposition painting over the entire part thereof. The electrodeposition coated film is then formed thick by the characteristic possessed by the edge rust preventive primer coated to the edge part 11, i.e., sacrificial corrosion inhibitive effect of zinc and the electrical conductivity thereof. The member is finally subjected to paint baking 13. The rust preventive power of the edge part, etc., is thus improved and the need for using a rust preventive steel sheet is eliminated.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a rust prevention method for edges, and more particularly, to a rust prevention method for areas where it is difficult to form a coating film such as edges, spots, welds, etc. of an automobile body groove member. .

[Conventional technology]

Automatic 1! Among the structural members of the car body, it is extremely difficult to form a coating film on the edges of those that have sharply shaped parts called edges. 1 is pulled toward the flat portion 2 and becomes thinner. Edges are easily affected by rainwater, wind and snow, so a thicker coating film should be formed than any other part, and in order to prevent rust from forming on these edges, structural members Even if the overall thickness of the coating film is reduced, it is merely a passive measure to thicken it and leave a coating film on the edges. Additionally, the entire component is constructed using rust-proof steel plate material. [Problems to be Solved by the Invention] However, as mentioned above, edges where it is difficult to form a coating film are susceptible to corrosion from rainwater, snow, etc. However, there are many things that go unnoticed, and there is a problem of allowing rust to occur without realizing it. When a rust-proof steel plate material is used, there is an undeniable increase in cost, and the steel plate material has problems such as poor adhesion of the coating film and poor durability. [Technical means for solving the problem] Therefore, the present invention protects the edges, etc., which are easily corroded, with a thick coating film, and furthermore, it is self-staining! The purpose is to ensure that a thick coating film is formed during the ill painting process for certain parts of the 71 car body, and after chemical conversion treatment, zinc-containing high viscosity coating is applied to car body components with edges etc. The rust-preventing primer coating is applied to at least the edge portions, etc., and then an N coating is applied to form an N-adhesive coating film on the rust-preventing primer coating. [Embodiment 1] Hereinafter, an embodiment of the present invention will be explained with reference to FIG. 1 attached. First, the oil film and dirt on the surface of the automobile component parts 10 are removed by chemical conversion treatment. Then, a zinc-containing high-viscosity paint 12 with suppressed fluidity during II smoldering is applied to the entire car body component 10 of the self-aS that has undergone chemical conversion treatment.
(hereinafter referred to as edge rust prevention primer) is applied to the entire surface including the edge portion 11 [II]. Thereafter, electrodeposition coating is applied to the entire body component 10 of the automobile [I[I]. At this time, the electrodeposited coating film is formed thickly due to the characteristics of the edge anti-corrosion primer applied to the edge portion 11, that is, the sacrificial anti-corrosion effect of zinc and the conductivity. Finally, paint baking 13 is applied [IV]. [Effects of the Invention] As is clear from the above description, the present invention has the following effects. (f) The rust prevention ability of edges, spots, welds, etc. is improved. (2) It is possible to reduce costs by eliminating the need for rust-proof steel plates used to prevent rust on the edges. (C) The rust-proof steel plate has a problem with the adhesion of the paint film, but the adhesion of the paint film is improved. (d), Product fil [i Ia ffi improvement t le.

[Brief explanation of the drawing]

FIG. 1 is a process explanatory diagram of the present invention, and FIG. 2 is an enlarged sectional view of a conventional edge portion. 10... Automobile body constituent member, 11... Edge portion.

Claims (1)

[Claims] (1) For automobile body components with edges etc.
After chemical conversion treatment, a zinc-containing high-viscosity rust-preventing primer coating is applied to at least the edge portions, etc., and then electrodeposition is applied to form an electrodeposited coating film on the rust-preventing primer coating. Rust prevention method.