The present invention relates to plated automotive parts and to methods of plating automotive parts.
As shown in
a details a conventional method of plating parts of the type shown in
The chrome plating gives the automotive part an attractive appearance and protects the part from scratches and rust because chromium metal has a high surface hardness and excellent wear and corrosion resistance. Additionally, when chromium metal is used to plate an automotive part such as a seatbelt tongue, use of chromium metal ensures easy fastening and releasing of the buckle and reliable latching due to the high surface hardness and excellent wear and corrosion resistance.
However, the chromium plating process requires the use of hexavalent chromium. Hexavalent chromium is a specified toxic substance, and its use requires treatment of wastewater and exhaust air to remove hexavalent chromium. Thus, manufacturers using hexavalent chromium must invest in, operate, and maintain a detoxification system and must pay additional costs to meet local regulatory requirements.
b details a conventional method of detoxifying wastewater and exhaust air generated during the process shown in
Even when the detoxification treatment is strictly managed, the use of hexavalent chromium presents environmental and safety risks. Such risks include leakage of hexavalent chromium from the manufacturing process potentially resulting in air, soil, and/or water contamination and adherence of hexavalent chromium to products potentially creating adverse health effects in persons exposed to the hexavalent chromium.
Additionally, manufacturers desiring to use hexavalent chromium must satisfy local regulatory requirements and obtain approval and licensing to use hexavalent chromium. Obtaining approval and licensing can be a lengthy process and, in some cases, approval may be impossible to obtain. Even if approval is obtained, risks to the manufacturer include production stoppages due to releases of hexavalent chromium, compensation paid to parties injured by hexavalent chromium contamination, and the cost of environmental cleanup due to hexavalent chromium pollution.
Thus, although chrome has proven to be an effective plating material, its use raises environmental concerns. What is needed, therefore, is an automotive plating and method of plating which, like chrome, provides effective plating properties but which is more environmentally friendly than chrome.
According to an embodiment of the invention, a plated automotive part and method of plating are provided. One or more semi-bright finish layers of nickel may be plated onto an automotive part. One or more bright finish layers of nickel may be plated onto the outermost, semi-bright finish layer of nickel. One or more layers of a hard coat may be plated onto the outermost, bright-finish layer of nickel. According to a preferred embodiment, the hard coat has a pencil hardness of 4H or greater.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and are not restrictive of the invention as claimed.
These and other features, aspects, and advantages of the present invention will become apparent from the following description, appended claims, and the accompanying exemplary embodiments shown in the drawings, which are briefly described below.
a is a block diagram of a conventional plating method;
b is a block diagram of a conventional wastewater and exhaust air treatment method;
a is a cross-sectional view of an automotive part covered with a plating material according to an embodiment of the present invention;
b is a cross-sectional view of an automotive part covered with a plating material according to an embodiment of the present invention;
a is a block diagram of a plating method according to an embodiment of the present invention;
b is a block diagram of a wastewater treatment method according to an embodiment of the present invention; and
Embodiments of the present invention will be described below with reference to
As shown in
The hard coat layer 18 may be clear so that the automotive part 110 has a metallic appearance of Ni. The hard coat layer 18 may have a pencil hardness of about 4H or greater and a thickness D1 of about 1 μm or greater. For example, the thickness D1 may be about 5 μm or greater. The hard coat layer 18 may comprise, for example, a material such as epoxy, acrylic, polyester, urethane, or melamine alkyl. The hard coat material according to the present invention is a more environmentally friendly material than conventional chromium plating material.
According to an embodiment of the invention, the thickness D1 of the outer layer 18 is about 6 μm or greater, and the outer layer 18 has a pencil hardness of about 4H or greater. In addition, although only one outer layer 18 is contemplated in this embodiment, more than one layer may be appropriate for some applications and are, therefore, fully within the scope of the invention.
According to another embodiment, the outer layer 18 is an inorganic hard coat layer such as, for example, an Si—R linked siloxane of a silicone containing compound as described in Japanese Patent Application No. JP2004-501233, incorporated by reference herein. In this embodiment, the outer layer 18 may have a pencil hardness of about 7H or greater and a thickness D1 of about 1 μm or greater.
According to another embodiment of the invention, the outer layer 18 of an automotive part 210 includes a first layer 18A of the hard coat and a second layer 18B of the hard coat, as shown in
According to an embodiment, after the hard coat layer 18 is applied, the layer 18 is cured using a curing process that may include application of one or more of the following: (a) ultraviolet light; (b) heat; (c) far infrared radiation; and/or (d) near infrared radiation to the automotive part.
a details a method of plating automotive parts of the type shown in
Each of the above-described steps is similar to corresponding steps of the conventional method shown in
It should be recognized, as indicated by dashed lines in
Similarly, as indicated by dashed lines in
Finally, as indicated by dashed lines in
b details a method of treating wastewater according to an embodiment of the present invention. Specifically, in step S101 (which preferably occurs during and/or after steps S1 to S5 in
Each of the above-described steps is similar to corresponding steps of the conventional method shown in
In an automotive part plated according to the method embodiments described above, the hard coat layer 18 may have a lower hardness and poorer wear resistance than conventional chromium plating. Thus, according to an embodiment of the present invention, the plated part may be protected from wear by minimizing the friction against the surface of the plated part. To protect the plated part (e.g., a seatbelt tongue), components in frictional contact with the plated part (e.g., a base and a latch of a seatbelt buckle) may include a coating containing molybdenum disulfide or fluorocarbon resin powder or may be treated with manganese phosphate plating or zinc plating having lower hardness than that of the alloy plating.
Thus, according to embodiments of the present invention, the use of a specified toxic substance in the plating of automotive parts is eliminated so that environmental protection and human safety is improved, wastewater and exhaust air treatment is improved, and manufacturing cost is reduced.
Given the disclosure of the present invention, one versed in the art would appreciate that there may be other embodiments and modifications within the scope and spirit of the invention. Accordingly, all modifications attainable by one versed in the art from the present disclosure within the scope and spirit of the present invention are to be included as further embodiments of the present invention. The scope of the present invention is to be defined as set forth in the following claims.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 60/561,531, filed Apr. 13, 2004, incorporated by reference herein.
Number | Date | Country | |
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60561531 | Apr 2004 | US |