JPS6130633B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to improvements in coating methods.

In order to save energy in the painting process and prevent pollution, it is considered that the paint drying process can be carried out at a lower temperature and in a shorter time, and the paint can be made to have a higher solidity. A two-component paint comprising a curing agent can easily satisfy the above requirements.

However, the pot life of the above two-component paint after mixing the base agent and curing agent is short, for example, about 6 hours, so the unused mixed paint must be disposed of. There was a problem that the yield was poor.

To solve this problem, a static mixer has been devised that mixes the two liquids just before the spray gun, but this mixer has many baffles installed in the narrow pipe to create turbulence in the flow of the two liquids. However, the structure is complicated and large, the paint tends to clog, and the cost is high.Also, if the static mixer and spray gun are not thoroughly cleaned at the end of the painting process, the hardening agent will harden the main agent. There was a problem that the workability was poor because it was stored away. The present invention solves the above-mentioned problems, and is aimed at, in a coating method using a paint consisting of at least a base ingredient and a curing agent or a curing accelerator, by allowing the base ingredient and the curing agent or curing accelerator to flow out independently into high-speed airflow. The atomized mixture is moved almost linearly toward a nozzle while being atomized and mixed, and the atomized mixture is jetted out at high speed from the nozzle toward a fluid collision disperser to reduce the pressure change and flow that occur when it collides with the fluid collision disperser. This invention relates to a coating method characterized by forming an ultra-fine mixture dispersed by turbulence and rapid changes in direction, and applying this ultra-fine mixture to an object to be coated.

Therefore, the base resin and the curing agent or curing accelerator are atomized and mixed at the same time, resulting in good workability.Also, since the base resin and the curing agent or curing accelerator are not mixed in advance, it is not possible to mix them as before. There is no need to dispose of unused paint,
It is possible to use a low-temperature, short-time curing type paint that is less expensive and has a shorter usable life, thereby making it possible to lower the baking drying temperature and shorten the time. Furthermore, simply by flowing the main agent and the curing agent or curing accelerator into a high-speed air stream, both agents can be reliably mixed and atomized, and the structure is simple.

Examples of the present invention will be specifically described below. In the first embodiment shown in FIG.
The inlet pipe 2 has its left end connected to a high-pressure gas (air) supply source (not shown), a cylindrical pipe 3 fixed to its right end, and a reduced diameter part 6 in the middle.
A small diameter part 7 and an enlarged diameter part 0 are provided, and the ends of the first and second supply pipes 8 and 9 are opened in the small diameter part 7.
The right end of the cylindrical tube 3 forms a nozzle 10, and the dispersion angle adjuster 4 is a cylindrical body provided on the right outer periphery of the cylindrical tube 3, and the right end thereof is formed into an acute angle shape 11. Further, the fluid collision disperser 5 is supported by two stays 12 installed on the inner wall of the cylindrical tube 3, is located on the central axis in the longitudinal direction of the cylindrical tube 3, and extends to the right of the dispersion angle adjuster 4. a shaft 13, and a disk 1 fixed to the right end of the shaft 13 and having an acute-angled outer periphery.
It consists of 4.

The first supply pipe 8 is connected to a color change device 16 through a flow control device 15 . This color changing device 16 includes a thinner supply port 17, two main agent supply ports 18,
19 is provided. The first base agent supply port 18 is connected to a first closed loop 20 which returns from the base agent reservoir 22 via the paint regulator 35 to the base agent reservoir 22 via the pump 21.
It is connected to the. The main agent reservoir 22 stores a red main agent of a two-component paint. Further, the second base agent supply port 19 is connected to a second closed loop 23 that returns from the base agent reservoir 25 to the base agent reservoir 25 via the pump 24 via the paint regulator 36, and the base agent reservoir 25 has a second base agent reservoir 25 different from the base agent reservoir 22. The main ingredient of color (yellow) is stored.

The second supply pipe 9 is connected to a three-way valve 26 through a flow rate control device 15, and the inlet of the three-way valve 26 is connected to a curing agent reservoir 28 via a pump 27. The return port is also connected to the curing agent reservoir 28, and a third closed loop 30 is formed by the curing agent reservoir 28, the three-way valve 26, and the pump 27. The curing agent reservoir 28 stores a curing agent for a two-component paint. 29 is an object to be painted.

With the above configuration, when painting the object 29, the pumps 21, 24, 27 are first driven, and the first and second closed loops 20, which are composed of the main agent reservoirs 22, 25, the pumps 21, 24, and the main agent reservoirs 22, 25, are driven. ,2
The main agent is circulated through the curing agent reservoir 28.
The curing agent circulates within a third closed loop 30 consisting of the pump 27, the three-way valve 26, and the curing agent reservoir 28. Furthermore, 2 to 6
Supply air with a pressure of Kl/cm ² .

Next, when painting the object red, the color change device 16 is operated to connect the first closed loop 20 and the flow rate control device 15, and the red base agent is transferred from the base agent reservoir 22 to the paint regulator 3 by the pump 21.
5. The main agent is sent to the first supply pipe 8 through the color change device 16 and the flow rate control device 15. In addition, the curing agent is 3
The third closed loop 30 is opened by operating the direction valve 26.
The paint regulator 36 and the flow rate control device 15 send an amount corresponding to the amount of the main agent to the second supply pipe 9.

Then, a fixed amount of the main agent and curing agent each flow out from the first and second supply pipes 8 and 9 into the high-speed air flowing through the small diameter portion 7. Then, the base agent and curing agent are atomized and mixed in high-speed air and moved almost linearly toward the nozzle 10 of the cylindrical tube 3, and this atomized mixture is jetted out at high speed from the nozzle 10 and is dispersed by fluid collision. The mixture collides with the vessel 5, and at the same time is compressed, expands and disperses in all directions, and further promotes atomization and mixing.

The subsequent atomized mixture ejected from the nozzle 10 collides with this expanded and dispersed atomized mixture, and is bound by the acute angle 11 of the dispersion angle adjuster 4 and the acute angle circumference of the fluid collision disperser 5. It is rapidly dispersed to the outside, which further advances the atomization and mixing of the base agent and curing agent, and this ultra-atomized mixture adheres to the object to be coated. Then, the main ingredient is cured by the action of the curing agent.

Also, when applying yellow, operate the color change device 16 to cut off communication to the first closed loop 20,
The thinner supply port 17 is opened, and the thinner flows from the supply port 17 into the atomization mixing device 1 through the flow rate control device 15 and the first supply pipe 8, and is ejected to the outside by a high-speed air flow. At this time, the color changing device 16,
The red base agent adhering to the flow rate control device 15, the first supply pipe 8, the pipe line connecting them, and the inside of the atomization mixing device 1 is washed away. Next, operate the color change device 16 to connect the second closed loop 23 to the color change device 16,
The yellow main agent is transferred from the main agent reservoir 25 to the color changing device 16, the flow rate control device 15, the first supply pipe 8, and the atomization mixing device 1.
The mixture is mixed with a curing agent into fine particles in the same mixing device 1, and then applied to the object to be coated.

Therefore, since a two-component paint consisting of a base agent and a curing agent is used, it is possible to lower the temperature and shorten the time during the baking drying process, resulting in energy savings, lower costs, and improved work efficiency. .

In addition, since the main agent and curing agent are mixed in the atomization mixing device 1, it is possible to use the remaining paint at the end of the painting work (when the device is finished operating), unlike the conventional method in which the two liquids are mixed in advance. There is no need to dispose of it, and the yield of paint is good.

Furthermore, the atomization mixing device 1 has a simpler structure and lower cost than conventional static mixers.
Furthermore, sufficient mixing and atomization can be achieved without causing clogging.

In addition, the mixing of the base agent and the curing agent is carried out in the atomization mixing device 1.
Since the process is carried out within a room, the usable life of the mixed paint can be extremely shortened, and as a result, a paint that cures at extremely low temperatures and in a short time can be used.

In addition, in the above embodiment, the first and second supply pipes 8,
9 is opened in the small diameter part 7, but it may be provided in the enlarged diameter part 0.

Further, in the above embodiment, the main agent and curing agent are supplied to the atomization mixing device 1 through the first and second supply pipes 8 and 9, but a third supply pipe is provided from which thinner is supplied and the paint is It can also be diluted.
In addition, a curing accelerator (S _N , etc.) is supplied from the third supply pipe.
can also be supplied to accelerate curing.

Furthermore, it goes without saying that four or more supply pipes can be opened in the atomization mixing device 1 of the above embodiment to supply four or more liquids of paint and additives. The two-component paint consisting of a main agent and a curing agent used in the above examples includes, for example, a urethane resin paint, a polyester resin paint, an epoxy resin paint, an acid-curable aminoalkyd resin paint, and the like.

It is also possible to use a two-component or more multi-component paint in which the acid catalyst, which is a curing accelerator, is supplied from the second supply pipe and the melamine-alkyd or acrylic-melamine resin paint is supplied from the first supply pipe. It's good.

Components in the second embodiment shown in FIG. 2 that are common to the first embodiment will be described with the same reference numerals. In FIG. 2, the first closed loop 20 consists of a main agent reservoir 22, a first pump section 32 of a gear pump 31, and a three-way valve 33, and the discharge side of the three-way valve 33 is connected to the first supply pipe 8 of the atomization mixing device 1. It is connected to the. The third closed loop 30 includes a curing agent reservoir 28 and a gear pump 31.
It is formed from a second pump section 34 and a three-way valve 26. The gear pump section 31 causes the first and second pump sections 32 and 34 to always discharge a constant amount of the main agent and curing agent.

Therefore, when painting, the gear pump 31 is first driven and the first and third closed loops 20,
The main agent and curing agent are circulated within the container 30. Next 3
The first and third closed loops 2 are operated by operating the direction valves 26 and 33.
Stop the circulation within the first and second supply pipes 8 and 9.
so that the base agent flows from the first supply pipe 8 into the high-speed airflow flowing through the atomization mixing device 1, and the curing agent also flows from the second supply pipe 9 into the high-speed airflow flowing through the atomization mixing device 1. Each of them is flowed out, atomized and mixed and dispersed, and this atomized mixed and dispersion is applied to an object to be coated.

Therefore, since one gear pump 31 discharges the main agent and the curing agent in fixed amounts, the number of pumps can be reduced, and there is no need to provide a flow rate control device, so the cost of the coating equipment can be reduced.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a first embodiment of the invention, and FIG. 2 is an explanatory diagram showing a second embodiment of the invention. 1: Atomization mixing device, 4: Dispersion angle adjuster, 5:
Fluid collision disperser, 8, 9: Supply pipe, 15: Flow rate control device, 16: Color change device, 21, 24, 27: Pump, 22, 25: Main agent reservoir, 28: Hardening agent reservoir, 2
0, 23, 30: closed loop, 31: gear pump.

Claims (1)

[Claims] 1. In a coating method using a paint consisting of at least a base agent and a curing agent or a curing accelerator, the base agent and the curing agent or curing accelerator are flowed out independently into a high-speed air stream, and mixed into atomized particles almost linearly through a nozzle. This atomized mixture was then ejected at high speed from a nozzle toward a fluid collision disperser, and was dispersed by the pressure change, flow turbulence, and sudden direction change that occurred when it collided with the fluid collision disperser. A coating method characterized by forming an ultra-fine particle mixture and applying this ultra-fine particle mixture to an object to be coated.