JP3247576B2 - Paint film durability evaluation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to "raining" and "etching" (the generation of fine linear rust like edging) on coatings of automobiles and various vehicles, and coatings of buildings. The present invention relates to a test apparatus which artificially promotes and reproduces a deterioration effect caused by acid rain, which causes corrosion such as bronze statues and marble statues, and accelerates the deterioration of concrete.

[0002]

2. Description of the Related Art Conventionally, as a corrosion acceleration tester widely used, 5% neutral salt water is continuously sprayed on a sample in a test tank controlled at a constant temperature and humidity of 35 ° C. and 98% RH. In a salt spray tester for performing a salt spray test method specified in JIS Z 2371, or in a test tank controlled in a constant temperature and humidity atmosphere of 50 ° C. and 98% RH, cupric chloride is converted to 5% neutral salt water. There is a CAS tester for performing a CAS test method specified in JIS H8502 in which a small amount of acid or acetic acid is added to continuously spray an acidic solution of pH 3 onto a sample. However, the deterioration phenomena caused by these test machines, that is, the form of rust generation often differed from the outdoor form.

[0003] Recently, a combined cycle corrosion test method has been carried out as a method that can approach and accelerate the outdoor deterioration phenomenon as much as possible. In the same test tank, for example, a salt spray test is performed for 2 hours, a dry test is performed for 4 hours, and a wet test is performed for 2 hours.
This is a test method in which a test performed in the order of time is defined as one cycle, and this cycle is repeated a predetermined number of times.

FIG . 4 shows an example of an apparatus for performing the above-mentioned combined cycle test. The test tank 30 has a double structure of an inner tank 31 and an outer tank 32 and is closed by an upper lid 33. I have. The space between the bottom of the inner tank 31 and the bottom of the outer tank 32 is a water tank 34 in which water is stored. Test temperature, ie inner tank 31
The internal temperature is controlled by heating water in a water tank 34 with a water heater 35. A spray tower 37 provided with a spray nozzle 36 for spraying a test solution is vertically arranged in the center of the bottom of the inner tank 31. The spraying of the salt solution is performed by injecting saturated air from an air saturator 38 disposed outside the test tank 30 at a constant pressure from the air nozzle 39 side of the spray nozzle 36, and generating a negative pressure to the solution nozzle 40 side of the spray nozzle 36. From the spray tower 37
The salt solution stored in the lower solution reservoir 41 is suction-sprayed, is concentrically and uniformly sprayed into the test tank 30 from above the spray tower 37, and is vertically dropped on the surface of the sample 17. The test solution is supplied to the solution reservoir 41 from a solution tank 42 arranged outside the test tank 30. In the drying test, a hot air blower 44 composed of the heater 10, the blower 43, and the like is arranged outside the test tank 30, and hot air is fed into the test tank 30 from an inlet 45 provided in the test tank 30. Has become. The humidity test is performed by providing a heater (not shown) for heating the water inside and a humidity generator 47 provided with a foaming tube 46 for feeding a certain amount of air at the bottom of the inner tank 31. ing. 48 is an air saturator 3
8 is an air compressor that sends compressed air to a foaming tube 46 of a humidity generator 47.

[0005]

In order to reproduce corrosion caused by acid rain using the conventional corrosion acceleration tester and the combined cycle tester described above, even if a test is performed using an artificial acid rain solution as a test liquid, the coating film cannot be obtained. For example, the form of corrosion is such that the coating film is turned up, peeled off, red rust from the substrate due to the occurrence of pinholes, cracks in the coating film, etc., especially on the exterior of automobiles placed outdoors. The common forms of corrosion, such as "raining" and "etching", caused by acid rain are not reproduced.

[0006] In the combined cycle corrosion tester, when spraying is performed, the solution becomes fine particles and adheres to the coating surface of the sample, and the fine particles are combined to form a uniform thin water film. This is dried by hot air, the water evaporates, and in the process the components are concentrated.

[0007] Compared to the case of an automobile placed outdoors, the rain falling on the coating film is relatively large particles (water droplets). Although it becomes a film, in many cases, the coating film surface is in a state where water droplets adhere. When the water droplets adhere to the sunlight after rainfall, the temperature of the body rises due to the radiant heat of the sunlight, and the components included in the water droplets, such as acid rain components, evaporate and concentrate. Is done. In addition, the water droplets adhere to the coating in the form of a lens, and the lens effect condenses sunlight. It may be different.

[0008] As described above, the conditions under which the exterior coating film of an automobile or the like placed outdoors is exposed cannot be reproduced by a conventional corrosion acceleration tester or a combined cycle corrosion tester. Is not reproduced. For this reason, there has been an urgent need to develop an accelerating device capable of reproducing the above-mentioned specific corrosion.

[0009]

To solve the above-mentioned problems, the following means are employed. That is, the infrared lamp installed in the ceiling portion above the test chamber for illuminating the sample, infrared
Attached directly to the sample surface to contact the ceiling of the test tank below the lamp , to separate the infrared lamp from the test tank, and to send a temperature signal to the controller that controls the radiant energy of the infrared lamp. A coating film durability evaluation device provided with a sample surface temperature detecting element and a temperature and humidity control means for circulating heated air and humidified air in the test tank to control the temperature and humidity in the test tank .

And a reflector disposed above the infrared lamp for uniformly and efficiently irradiating the sample with the irradiation light.
And a sample stage capable of controlling the temperature of the sample from the back side, and a test that is located above the sample stage, moves on the horizontal plane at regular intervals in the XY-axis direction, and drops the test liquid at a plurality of locations on the sample surface A coating film durability evaluation device provided with a dropping means .

[0011]

By providing an infrared lamp in a test tank whose temperature and humidity can be controlled, for example, a sample in which a test liquid (for example, an artificial acid rain solution) having the same size as a raindrop is dropped is placed in this test tank. By arranging it inside, the sample can be dried with the light of the infrared lamp and its radiant heat in the same way that the sample is dried outdoors with the radiant heat of the sun,
A process similar to the process of concentrating water drops (raindrops) outdoors can be reproduced. In addition, the surface temperature detection element is directly attached to the sample surface, and the radiant energy of the infrared lamp is controlled by the temperature signal. The process of concentrating raindrops due to differences in sample surface temperature can be reproduced.

In the above-mentioned test tank, XY on a horizontal plane
By providing a test liquid dropping means for moving the test liquid at regular intervals in the axial direction and dropping the test liquid, the solution is sprayed as fine particles on the sample surface as in the prior art, that is, the sample surface is covered with a water film. In addition, a chemical solution of the same size as raindrops can be dropped onto the sample surface, and the temperature and humidity in the test tank can be controlled. It can be reproduced under the same conditions as the temperature and humidity at the time.

[0013]

An embodiment of the present invention will be described below with reference to the drawings. Figure 1 is a fragmentary front view of the coating durability evaluation apparatus Kazumi施例of the present invention, FIG. 2 is a plan view of FIG. 1, FIG. 3 is a side view of FIG.

1, 2 and 3, the coating durability evaluation apparatus 1 of this embodiment has an opening on one side (front) of a closed box 3 composed of a heat insulating wall 2. A door 4 is provided to cover this. An opening is also provided in the ceiling of the box 3, and a heat-resistant transparent glass plate 5 (Pyrex glass in this embodiment) is fitted into the opening. Also,
An upper end is in contact with the periphery of the opening of the box 3 ceiling, and a lower end is in contact with the bottom to provide a flat U-shaped partition wall 6. The inner tank 7 is formed in the box 3 in contact with the side periphery of the opening. An air outlet 8 and an air inlet 9 for circulating air are opened on both side walls of the inner tank 7, and a heater 10 and a cooler 11 are arranged behind the space between the inner tank 7 and the heat insulating wall 2. is there. In the rear space, a blower 12 is provided on the suction port 9 side, and a humidifier 13 provided outside the box 3 feeds humidified air into the rear space. Therefore, the space between the inner tank 7 and the box 3 becomes an air passage, and the air blower 12
Is operated, the temperature-controlled and humidified air circulates back to this air path through the air outlet 8 and the air inlet 9 provided in the inner tank 7, and the temperature and humidity in the inner tank 7 are determined. You.

A box-shaped body 3 provided with one rod-shaped (fluorescent lamp-shaped) infrared lamp 14 above the heat-resistant transparent glass plate 5 and provided with an opening.
Are provided in parallel with and horizontal to the side surfaces of. In order to effectively irradiate the light of the lamp 14 through the heat-resistant transparent glass plate 5 to the inside of the inner tank 7, a reflector 15 having a semicircular cross section is provided. At the bottom of the inner tank 7, a position where the light of the infrared lamp 14 is effectively irradiated, in this embodiment, at the approximate center of the inner tank 7, the rectangular sample table 16 is spaced from the partition wall 6.
Is arranged. In addition, the test temperature and humidity of the present apparatus are set to the temperature and humidity set in an unshown inner tank temperature and humidity setting device provided outside the box 3 by the outputs of a not-shown temperature sensor and humidity sensor arranged in the inner tank 7. Then, the heater 10, the cooler 11 and the humidifier 13 are controlled.

The temperature of the sample 17 is basically determined by the temperature in the inner tank 7 and the radiant heat of the infrared lamp 14. The temperature of the sample 17 is determined by the heat storage effect. (Even at the temperature measured at the location). This heat storage action also differs depending on the material, color and the like of the sample 17. Therefore, in the present invention, the sample temperature is measured using the surface temperature detection sensor 18 attached to the surface,
From the output, the infrared lamp 1 is set so that the sample surface is at a temperature set in a sample temperature setting device 19 provided outside the box 3.
4 is controlled.

[0017] Now, test by the apparatus in advance controlled to within the inner tub 7 is a constant temperature and humidity, the test liquid on the surface of the specimen 17 in a state of being placed on the sample stage 16 (e.g. (Artificial acid rain solution) is added dropwise.

Therefore, the irradiation light of the infrared lamp 14 is applied to the sample surface through the heat-resistant transparent glass plate 5, and the sample surface rapidly rises by the radiant heat, and the test liquid dropped on the sample surface starts to be concentrated. This concentration process takes into account the lens effect as well as under outdoor sunlight. Further, a sample temperature setting device 19 for setting an upper limit in advance so that the sample surface temperature does not abnormally rise above the temperature in the natural world.
And the surface temperature detection sensor 18
Will be maintained at its upper temperature limit.

The apparatus of this embodiment further drops a test solution.
Means and the temperature of the sample 17 can be controlled from its back side.
A sample stage 16 is provided . That is, FIGS.
In (3) and (3) , in order to drop a test solution, for example, an artificial acid rain solution, onto the sample 17 placed on the sample stage 16, the tip 20 is bent downward and the nozzle 20 whose tip is located above the sample stage 16 is provided in the inner tank 7. It is provided horizontally above. The horizontal portion of the nozzle 20 is provided with a long hole 21 provided horizontally above the air outlet 8 of the inner tank 7 and the box 3 at the same position as the long hole 21.
The box 3 protrudes out of the box 3 through a slot 22 formed in the side wall of the box 3, and is fixed to an XY table 23 driven by a stepping motor or the like fixed to the side wall of the box 3. The driving of the XY table 23 is controlled by a control unit (not shown) so that the perpendicular passing through the tip of the nozzle 20 can move over the entire surface of the sample table 16 and does not block the irradiation light of the infrared lamp 14 irradiated on the sample 17 You can move. A flexible pipe 24 is attached to the rear end of the nozzle 20, and the other end of the pipe 24 is connected to a test liquid dropper 25 disposed above the box 3. In this embodiment, the test liquid dropped from the dropper 25 through the nozzle 20 is adjusted to about 0.2 cc. The test liquid dropping means configured as described above allows the test liquid to be dropped at predetermined intervals in a desired range on the sample surface on the sample table 16. Further, the sample 17 placed on the sample stage 16 is
An electronic cooling element 26 is incorporated to cool the device from the back.

Therefore, in the test using the apparatus according to the present embodiment , the sample 17 placed on the sample stage 16 is subjected to a test solution (artificial solution) at predetermined intervals within a desired range on the surface thereof under a condition controlled at a constant temperature and humidity. The acid rain solution) is dropped, and after the drop, the nozzle 20 moves from above the sample table 16. Next, the infrared lamp 14
Is irradiated on the sample surface through the heat-resistant transparent glass plate 5, the sample surface rapidly rises by the radiant heat, and the concentration of the test liquid dropped on the sample surface starts. This concentration process takes into account the lens effect as well as under outdoor sunlight. Further, the output of the infrared lamp 14 is adjusted by the sample temperature setting device 19 and the surface temperature detection sensor 18 which set the upper limit in advance so that the sample surface temperature does not abnormally rise from the temperature in the natural world. Will be maintained.

The electronic cooling element 26 incorporated in the sample stage 16 can effectively cool the sample 17 from the back. That is, the test liquid dropped on the surface of the sample 17 cooled below the freezing point freezes on the surface of the sample. By irradiating with the infrared lamp 14 in this state, for example, it is used to reproduce a condition in which ice droplets attached to the sample 17 placed in an environment below the freezing point are gradually melted and dried and concentrated by sunlight. Can be.

[0022]

According to the present invention, a conventional corrosion promotion tester or a combined cycle corrosion tester cannot reproduce even the use of an artificial acid rain solution as a test liquid, ie, "raining" or "raining". "Etching" can be reproduced. Therefore, the acid rain resistance performance of the exterior coating film of an automobile or the like placed outdoors can be easily and accurately accelerated and reproduced, which greatly contributes to the research required for improving the coating film performance.

[Brief description of the drawings]

FIG. 1 is a front view of a main part of a configuration of an embodiment .

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a side view of FIG. 1;

FIG. 4 is a configuration diagram of a conventional combined cycle corrosion tester .

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 coating film durability evaluation device 5 heat-resistant transparent glass plate 6 partition wall 7 inner tank 10 heater 11 cooler 13 humidifier 14 infrared lamp 15 reflector 16 sample table 17 sample 18 surface temperature detection sensor 19 sample temperature setting device 20 nozzle 23 XY table 25 Test drop dropper 26 Electronic cooling element

Continuation of the front page (56) References JP-A-5-322471 (JP, A) JP-A-4-12249 (JP, A) JP-A-4-19544 (JP, A) JP-A-62-290523 (JP) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01N 17/00 JICST file (JOIS)

Claims (1)

(57) [Claims] 1. An infrared lamp installed above a ceiling of a test tank for irradiating a sample, a reflector installed above the infrared lamp for irradiating the sample uniformly and efficiently to the sample, and an infrared ray Touch the ceiling of the test tank below the lamp,
A heat-resistant transparent glass plate for separating the infrared lamp and the test tank, a temperature-controllable sample stage that controls the temperature of the sample from the back, and a sample stage above the sample stage that moves at regular intervals in the XY axis direction on the horizontal plane A test liquid dropping means for dropping a test liquid onto a plurality of points on the sample surface, a sample surface temperature detecting element directly attached to the sample surface to send a temperature signal to a controller for controlling the radiation energy of the infrared lamp, A coating film durability evaluation device comprising: a temperature and humidity control means for circulating heated air and humidified air in a test tank to control temperature and humidity in the test tank.