JPS6118471A - Coating method of automobile body with different colors by part - Google Patents

Abstract

PURPOSE:To improve productivity of the main top coating stage by coating in an intermediate coating stage the whole surface of an automobile body coated previously with an under coating film with a colored sealer in place of a conventional intermediate coating paint. CONSTITUTION:An automobile body W which has been coated with an electrodeposition coating film is conveyed to an intermediate coating booth 1 where the whole surface of the automobile body W is coated with a colored sealer adjusted to a same or similar color tone as a top coating paint having a low hiding power which has been coated in a main top coating booth 9 to form thus a coating film Pa. The coating is then subjected to drying and wet sanding, and coated with the first top coating film Pb on the bottom part of the automobile body in a first top coating booth 4. The car body is then conveyed through a drying oven 5, wet sanding section 14, and a masking section 15 to the first top coating booth 4 again. In this stage, color sealer film Pd is formed on the dust zone Pc while masking the coating film Pb, and the automobile body is conveyed after drying to the main top coating booth 9.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for separately painting an automobile body by separately painting the surface of an automobile body with a regular top coat and a low-hidden top coat. be.

C. Prior Art Conventionally, when the surface of an automobile body is painted separately using a normal top coat and a low-hidden top coat, the painting process is as shown in FIG. 1.

In Fig. 1, an intermediate coat colored gray in an intermediate coating process is applied to the entire surface of an automobile body (not shown) on which an electrodeposition coating film, which is an undercoat coating film, has been formed. After sanding, a regular top coat is applied to the lower side of the car body in a first top coat process. After the top coat is dried, the top coat is masked.

・Next, the masked car body is transported to the main top coating process, where a chromatic color sealer is applied to the upper sides and top of the car body. After the color sealer is dried, the masking provided at the lower side is removed and the color sealer portion is water polished.

Next, the top coat of the water-polished car body is masked again and it is returned to the main top coat painting process.
A low-hidden top coat and clear paint are sequentially formed on the upper side and top portion of an automobile body. After that, it is transported to a drying process, where the low-hidden top coat part and the clear paint part are dried, and the masking is removed.

As a result, a two-tone car body is obtained, in which a normal top coat is formed on the lower sides, and a low-hidden top coat is formed on the upper sides and the top.

However, in this method of separately painting automobile bodies, the area to be painted with the regular top coat is masked, a chromatic paint called color sealer is applied and dried in the main top coat process, and then the same coating is applied again. Since the product is returned to the main topcoat process and a low-hidden topcoat and clear paint are applied, the production capacity of the main topcoat process is halved, and the energy cost per car body doubles. There is a problem.

[Purpose of the Invention] The present invention has been made to solve the above-mentioned problems, and its purpose is to apply a paint to the entire surface of an automobile body on which an undercoat film has been formed, instead of using a normal intermediate paint in the intermediate coating process. To provide a method for separately painting an automobile body, which can improve the production capacity of a main top coating process and reduce the energy cost per automobile body by applying a chromatic color sealer.

[Structure of the invention]

In order to achieve the above object, the method of separately painting an automobile body according to the present invention is configured to separately paint an automobile body with a normal top coat and a low-hidden top coat. A color sealer is applied to the entire surface of the automobile body on which the undercoat film has been formed,
After drying and water polishing - Apply a regular top coat to a part of the car body in the first top coat process, and after drying, mask the top coat and apply a color sealer to the dusty area caused by the top coat. After drying, removing the masking, and sanding, the top coat is masked again, and a low-hidden top coat is applied to the parts of the car body other than the masked parts in the main top coat process.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the method for separately painting an automobile body according to the present invention will be described in detail with reference to the drawings.

FIG. 2 is a schematic cross-sectional view illustrating the painting equipment of the method for separately painting an automobile body according to the present invention, and FIG. 3 is a process diagram of the method for separately painting an automobile body according to the present invention.

In Fig. 2, reference numeral 1 denotes an intermediate coating booth, and on the downstream side of this intermediate coating booth 1, an intermediate coating film is baked and
A drying oven 2 for curing is provided continuously, and a water testing area 3 is provided on the downstream side thereof. Further, on the downstream side of the water testing area 3, a first top coat coating booth 4 and a drying oven 5 for baking and curing the first top coat film are successively installed, and on the downstream side thereof, a masking removal area 6 is provided. , a water testing area 7 and a masking area 8 are provided in this order. Furthermore, on the downstream side of the masking area 8, a main top coating booth 9 and a drying oven 1O for baking and curing the second top coating film are successively provided, and on the downstream side thereof, a masking removal area 11 is provided. It is being

A conveyor 12 is continuously installed from the intermediate coating booth 1 to the water testing area 11, and a bypass conveyor 13 is installed in parallel to the first top coating booth 4 and the drying oven 5. It is connected to the conveyor 12 on the upstream side of the top coating booth 4, and the other end is connected to the conveyor 12 on the downstream side of the drying oven 5. In the middle of this bypass conveyor 13, a wet polishing area 14 and a masking area 14, which are the first top coating area, are provided in sequence.

A method of separately painting an automobile body using the painting equipment configured as described above will be explained with reference to FIGS. 2 and 3.

In FIGS. 2 and 3, W is an automobile body. Oil, fat, fingerprints, dust, etc. adhering to the surface of the automobile body W are cleaned and removed using a degreasing agent, and then this is washed with water. Since many water droplets adhere to the surface of the automobile body W after being washed with water, these are removed by blowing clean air or hot air. After that, the undercoat film (electrodeposition paint film)
5. To improve the adhesion between the car body and the car body W. A chemical conversion coating (not shown) of zinc phosphate, iron phosphate, etc. is formed.

The automobile body W on which the chemical conversion coating has been formed is transferred to the next process, which is an electrodeposition coating process. In this electrodeposition coating process, an electrodeposition coating film (not shown) is formed on the entire surface of the automobile body W in a range of 20 to 40μ. As the electrodeposition coating method, either the conventionally commonly used method of painting using an anionic electrodeposition paint or the method of painting using a cationic electrodeposition paint is adopted. be able to. Moreover, there is no need to set special conditions for electrodeposition coating, and conditions that are generally employed can be applied as they are.

The automobile body W on which the electrodeposition coating film has been formed is subjected to the following process -
It is transferred to the intermediate coating booth 1.

In this intermediate coating booth 1, 20 to 40μ of a chromatic color sealer that is toned to be the same color or similar color to the low-hidden topcoat paint that will be applied later in the main topcoat coating booth 9 is applied to the entire automobile body W. A first color sealer coating film Pa is formed on the surface. The color sealer used here is not particularly limited, and for example, any of organic solvent-based paints, water-based paints, and powder paints can be used. In addition, these painting methods are suitable for each paint, such as air spray painting method,
Airless painting methods, electrostatic painting methods, etc. can be employed as appropriate.

The automobile body W on which the first color sealer coating film Pa has been formed is transferred to a drying oven 2, which is the next step.

In this drying oven 2, the first color sealer coating film Pa is baked and cured using drying means and drying conditions suitable for the first color sealer coating film Pa, and the means and conditions are not particularly limited.

Further, the automobile body W on which the first color sealer coating film Pa has been baked and hardened is transferred to the hydroponic area 3, where the first color sealer coating film Pa is water polished. In the hydroponic work at that time, either automatic or manual operation can be adopted.

The water-polished automobile body W is transferred to the first top coating booth 4, which is the next step. In this top coating booth 4, a first color top coat is applied to the lower side of the automobile body W in a range of 20 to 40μ to form a first top coat p.
b is formed. At this time, dust Pc from the top coat of the first color adheres over a certain width of the upper side.

As the first color topcoat used here, a commonly used topcoat can be used as is, and as with the color sealer coating, a coating method suitable for each paint can be adopted as appropriate. can.

The automobile body W on which the first top coat pb has been formed is transferred to the drying oven 5, which is the next step. In this drying oven 5, baking and drying are performed using drying means and drying conditions suitable for the first top coat pb.
The dust of the first top coat Pb is cured and transferred to the hydroponic area 14 of the bypass conveyor 13 for the next step.
The part is water-polished. - In the masking area 15, which is the next step, the wet-sanded automobile body W is masked with a masking material (not shown) such as paper or resin film at the formation area of the first top coat Pb, and then the first top coat Pb is masked again. It is transferred to the top coating booth 4. In this first top coating booth 4, the first top coat of the automobile body W is
A second color sealer coating Pd is formed by applying a second color sealer coating Pd to the dust Pc area caused by the colored top coat paint in a range of 5 to 10 μm. The color sealer used here is the same as the color sealer applied in the intermediate coating booth 1, and the color sealer and coating conditions are appropriately adjusted in the same manner as when forming the first color sealer coating Pa. Can be adopted.

The automobile body W on which the second color sealer coating film Pd is formed is transferred to the drying oven 5 which is the next step, and the second color sealer coating film Pd is is baked and hardened.

Thereafter, it is transferred to a masking removal area 6 where the masking is removed, and also transferred to a hydroponic area 7 where the second color sealer coating Pd is water polished.

The wet-polished automobile body W is masked again in the masking area 18 at the formation site of the first topcoat film Pb with a masking material such as paper or resin film, and then transferred to the main topcoat booth 9 for the next process. . In this main top coating booth 9, coating parts other than masking, such as the upper side and top part of the automobile body W, are coated with 20 to 40 coats of paint.
A second color topcoat with low hiding power is applied in the μ range to form a second topcoat film Pe, and a clear paint is applied on the surface to form a clear paint film Pf in a range of 5 to 10μ. It is formed.

The automobile body W on which the second top coating film Pa and the clear coating film Pf have been formed is transferred to the drying oven 10, which is the next step,
The second top coat P-e and the clear coat pr are simultaneously baked and cured using drying means and drying conditions suitable for the second top coat P-e and the clear coat pr. Then, the automobile body W on which both the coating films Pe and Pf have been baked and hardened is transferred to the next step, a masking removal area 11, where the masking provided at the lower side of the automobile body W is removed.゛Thus, the first top coat film p made of normal top coat paint
A two-tone car body W is obtained in which the color b is formed on the lower side and the second top coat Pe made of a low-hidden top coat is formed on the upper side and the top.

[Effects of the Invention] As explained above, in the method for separately painting an automobile body according to the present invention, in place of a normal intermediate coating paint in the intermediate coating process, the entire surface of an automobile body on which an undercoat film has been formed is coated. Since the paint is painted with color sealer, it is no longer necessary to move the car body twice during the main top coating process, which directly affects the production capacity of the painting line.
This has the effect of improving production capacity compared to the conventional separate painting method.

Further, in the present invention, there is no need to move the car body twice in the main topcoating process, thereby reducing the energy cost per car body.

Furthermore, the method for separately painting an automobile body according to the present invention has the effect of reducing additional capital investment that would otherwise be required using conventional equipment.

[Brief explanation of drawings]

FIG. 1 is a process diagram of a conventional method for separately painting an automobile body. FIG. 2 is a schematic cross-sectional view illustrating the painting equipment of the method for separately painting an automobile body according to the present invention. FIG. 3 is a process diagram of a method for separately painting an automobile body according to the present invention. 1・-・-・Intermediate coating booth 2・----m-・Drying furnace 3-・・Hydroponic area 4・・・・First top coating booth 5・・・・・-Drying oven 6...--Masking removal area 7--Hydroponic area 8--Masking area 9--Main topcoating booth 10--Drying oven 11- ---- Masking removal area 12 --- Conveyor 13 --- Bypass conveyor 14 --- Hydroponic area 15 ---- One -- Masking area Pa --- First Color sealer coating pb - - - - - First top coat Pc - - Dust Pd - - Second color sealer coating Pe - - - Second top coat

Claims (1)

[Claims] This is a separate painting method for car bodies, in which the car body is painted separately with a regular top coat and a low-hidden top coat, in which a color sealer is applied over the entire surface of the car body on which the base coat has been formed, and then dried.・After water polishing, a regular top coat is applied to a part of the car body in the first top coat process, and after drying, the top coat is masked and a color sealer is applied to the dust part caused by the above-mentioned top coat. , drying
A method for separately painting an automobile body, which is characterized by removing the masking and water-polishing, then masking the top coat again, and applying a low-obscuring top coat to parts of the car body other than the masked parts in the main top coating process. .