JP2001208675A - Accelerated exposure test method and accelerated exposure test equipment - Google Patents

Abstract

(57) [Problem] To provide an accelerated exposure test method and an accelerated exposure test apparatus capable of shortening the period (time) required for the test as compared with the accelerated exposure test by conventional artificial means. As an issue. An accelerated exposure test apparatus according to the present invention includes a test piece.
Container 2 having an internal space 21 capable of receiving and closing air therein and having a sealable internal space, an oxygen plasma generating / supplying unit 4 for supplying oxygen plasma to the internal space 21, and a gas containing water vapor or a mixture of water vapor and oxygen in the internal space 21. Gas supply units 5 and 6 for supplying gas containing both, a light irradiation unit 7 for irradiating the surface of the test piece 9 with light, and a discharge unit 8 for discharging a used substance from the interior space 21. It is characterized by the following.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an accelerated exposure test method and an accelerated exposure test apparatus which can be used in place of an outdoor exposure test and can reproduce material deterioration artificially in a short time.

[0002]

2. Description of the Related Art In general, outdoor exposure tests are carried out on various materials,
It is used when evaluating weather resistance from the degree of deterioration of materials (various characteristics) over time in a natural environment in a substance, product, or the like (hereinafter, referred to as a test piece).

However, in the outdoor exposure test, the deterioration of the test piece under the influence of sunlight, oxygen and humidity (moisture) in the atmosphere, temperature, etc. is slow, and it takes a long time until the weather resistance can be evaluated. Requires a period (eg, one year or more).

For this reason, in general, for example, when developing various products, it is necessary to know the deterioration of the test piece with the lapse of time in a short period of time, or to cope with the case where development is urgent. By performing accelerated exposure tests on
The same results as in the case of long-term outdoor exposure tests on test specimens were obtained in a short period of time.

An example of the results of an accelerated exposure test belonging to the prior art is shown.

A test piece prepared in advance and prepared [3.5 cm in width]
× electrodeposition on the surface of steel plate of length 15cm × thickness 0.8mm,
Apply in order of middle coat, top coat (white solid)
Painted plate with a layer of coating (60 degree gloss of 9
4)], an accelerated exposure test apparatus (Sunshine Weather Meter (manufactured by Suga Test Instruments)) was used to perform an accelerated exposure test method (JISA1415) for plastic building materials.
The decrease in gloss as the progress of deterioration of the coating film with the passage of time was measured, and the results are shown in FIG.

As a result, it took 1200 hours to obtain a deterioration equivalent to reducing the 60-degree gloss 94 of the test piece before the test to 89.

[0008]

Here, in order to improve the efficiency of the test, the inventor of the present application devised the above-mentioned test period (hour) when the conventional accelerated exposure test device (sunshine weather meter) was used. However, they have found room for improvement so as to obtain the results of durability deterioration in a shorter period (time), and have created new test methods and test apparatuses.

[0009] When the components of the test piece consist of a resin matrix and titanium oxide particles (white pigment) dispersed in the resin matrix, the degradation reaction that occurs when exposed outdoors can be divided into oxidation and hydrolysis. Of these, oxidation is further divided into oxidation occurring in the entire region of the resin matrix and oxidation involving a photocatalytic reaction occurring in a peripheral region such as titanium oxide particles dispersed in the resin matrix. That is, there are three types of degradation reactions caused by outdoor exposure: oxidation occurring in the entire region of the resin matrix, oxidation occurring in the peripheral region such as titanium oxide particles, and hydrolysis.

Therefore, in order to promote and reproduce the deterioration outdoors, it is necessary to accelerate and cause all of the above three types of deterioration reactions from outside. Among them, the present inventors have found that oxidation occurring in the peripheral region such as titanium oxide particles is remarkably promoted by irradiating light in a hydrogen peroxide solution, and the hydrolysis reaction generally includes water as a load factor. Is known to be easily accelerated by accelerated exposure tests.

However, among the above three types of deterioration reactions, there is no means for generating oxidation at high speed in the entire area of the resin matrix, so that an accelerated exposure test for accelerating and reproducing outdoor deterioration at high speed has been realized. Not.

The present invention has been made in view of the above problems, and an accelerated exposure test method and an accelerated exposure test apparatus capable of shortening the period (time) required for the test as compared with the accelerated exposure test using conventional artificial means. The task is to provide

[0013]

According to the accelerated exposure test method of the present invention, a first deterioration accelerating step of accelerating oxidative deterioration of a surface of a test piece by applying oxygen plasma to the surface of the test piece; A second degradation promoting step of causing the surface to undergo hydrolysis degradation or both hydrolysis degradation and oxidative degradation by causing at least one of water, light and oxygen to contain water to act on the surface. The accelerating step and the second deterioration accelerating step are each repeated at least once.

In the first deterioration accelerating step, the oxygen plasma can act on the surface of the test piece to increase the oxidation, and for example, can be performed in a shorter time than when the conventional accelerated exposure test apparatus (sunshine weather meter) is used. This can accelerate the deterioration of the surface.

In the second deterioration accelerating step, the surface of the test piece can be accelerated by hydrolysis or both hydrolysis and oxidation.

For this reason, by repeating the first deterioration promotion step and the second deterioration promotion step, it is possible to obtain a deterioration state almost the same as that obtained when the outdoor exposure test is performed in a short period of time.

[0017] As a member to be tested for the accelerated exposure test method of the present invention, for example, a coating film can be used.

As the coating film, for example, a coating film composed of a resin matrix and titanium oxide particles (white pigment) dispersed in the resin matrix can be used.

An accelerated exposure test apparatus according to the present invention comprises a container having an internal space capable of accommodating and removably accommodating a test specimen, an oxygen plasma generating / supplying unit for supplying oxygen plasma to the internal space, A gas supply unit for supplying a gas containing water vapor or a gas containing both water vapor and oxygen to the space, a light irradiation unit for irradiating light to the surface of the test piece, and discharging a used substance from the inside space And a discharge unit.

According to the accelerated exposure test apparatus of the present invention, the test piece is stored in the inner space of one container,
The first degradation accelerating step and the second degradation accelerating step of the accelerated exposure test method can be alternately repeated one or more times.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The second embodiment of the accelerated exposure test method of the present invention
Light emitted from an artificial light source or sunlight can be used as light used in the deterioration accelerating step and the accelerated exposure test device.

Any artificial light source can be used as long as it can irradiate the test piece with ultraviolet rays. If sunlight is used, the test piece should be controlled toward the sun using an automatic follower, etc. so that the test piece can be continuously irradiated, or the sunlight can be controlled by an optical cable, reflector, etc. It is preferable to perform position control for guiding the test piece to the test piece.

As the water used in the second deterioration accelerating step and the accelerated exposure test apparatus, water vapor, liquid water and an aqueous solution in which an oxidizing agent is dissolved can be used. Hydrogen peroxide or sodium hypochlorite can be used as the oxidizing agent. As the liquid water, it is preferable to use high-purity water (hereinafter, ion-exchanged water or the like) such as ion-exchanged water or distilled water. The reason for this is that the test results are excellent in reproducibility due to no influence of impurities. Further, as the aqueous solution in which the oxidizing agent is dissolved, it is preferable to use a hydrogen peroxide solution. This is because
This is because the oxidation reaction is promoted by oxygen generated from hydrogen peroxide.

The condition in which water is applied to the test piece in the second deterioration accelerating step means that a test piece is contained in a gas such as air or oxygen containing a predetermined moisture and adjusted to a predetermined humidity. The term refers to a state in which a test piece is exposed or a so-called immersed state in which a test piece is submerged below the water level of ion-exchanged water or a hydrogen peroxide solution.

The reason why the atmosphere when irradiating light is set to a relative humidity of 20% or more is that if the relative humidity is 20% or less, the rate of hydrolysis becomes insufficient.

The light used in the second deterioration promoting step is:
Ultraviolet rays that irradiate the surface of the test piece in a state of being immersed in an aqueous solution of an oxidizing agent such as hydrogen peroxide solution or ion-exchanged water or in an atmosphere having a relative humidity of 20% or more can be used.

When ultraviolet rays are irradiated while immersed in an aqueous solution of hydrogen peroxide or the like, an oxidizing agent such as hydrogen peroxide or the action of water and ultraviolet rays can be obtained at the same time. Can be As a synergistic effect in this case, oxidation occurring in a peripheral region such as titanium oxide particles (white pigment) is remarkably promoted.

[0028] The second deterioration promoting step may include irradiating the surface of the test piece with light in an aqueous solution containing the oxidizing agent.

The second deterioration accelerating step includes irradiating the surface of the test piece with light in an aqueous solution containing 0.001% to 60% by weight of a hydrogen peroxide solution; The method may include irradiating the surface with light in water or an atmosphere having a relative humidity of 20% or more.

The hydrogen peroxide solution has a weight concentration of 0.001% to
The reason for setting the range to 60% is that if the content is less than 0.001%, the effect of the hydrogen peroxide solution becomes insufficient, and the effect of using the hydrogen peroxide solution cannot be expected. This is because there is a risk that a reaction will not occur.

The container of the accelerated exposure test apparatus of the present invention is a container that allows a test piece to be taken in and out of the internal space and that can be held in a sealed manner. The container is preferably robust. As the material of the container, for example, stainless steel can be used.

As the container, a container having a window which is transparent to the ultraviolet rays on a wall defining an internal space can be used. As a material of the window, for example, quartz glass or the like can be used.

The light irradiating section may be one provided outside the container or one provided in the internal space of the container.

The light irradiator may be of a type having the artificial light source capable of irradiating the test piece with light from the outside of the container through a transparent window, or may be provided with a test piece through the transparent window from the outside of the container. For example, a system that can radiate sunlight can be used.

The supply unit includes an open / close valve which can communicate with and shut off the internal space of the container, and is provided with a gas (air or oxygen) and a liquid (water or an aqueous solution of hydrogen peroxide).
One injection device having a function of supplying the type to the internal space, and an opening / closing valve formed separately from each other and capable of communicating with and shutting off from the internal space of the container, so that gas (air or oxygen) is supplied to the internal space. A gas injecting device having a function of supplying a liquid and an injecting device having a function of supplying a liquid (aqueous solution such as water or hydrogen peroxide) to an internal space can be used in combination.

The oxygen used in the second deterioration accelerating step and the accelerated exposure test device was obtained by various production methods, contained in the atmosphere (air), and released from various substances by a reduction reaction. What can be used.

It is preferable that the accelerated exposure test apparatus is used in combination with a temperature controller. The temperature controller holds the test piece and the gas or liquid contained in the internal space of the container at a predetermined temperature. As the temperature control unit, for example, a temperature control device that is installed outside or inside the container and has a built-in heater, and a hollow part that is installed on the outer periphery of the container and allows a heat medium such as hot water, hot air, and heated steam to flow Can be used.

[0038]

Example 1 Example 1 of the accelerated exposure test method of the present invention will be described below.

In the accelerated exposure test method of Example 1, a test piece prepared in advance before the test is used. That is, the test piece is 3.5 cm wide × 15 cm long × 0.8 mm thick.
Electrodeposition, intermediate coating, top coating (white solid)
This is a painted plate prepared by applying a coating to three layers.

In the accelerated exposure test method of Example 1, the test specimen was subjected to the first degradation promotion step, the first and second degradation promotion steps 1 and 2, and the measurement of 60-degree gloss in one cycle. , And the above cycle is repeated six times.

(First Degradation Acceleration Step) In the first degradation acceleration step, oxygen plasma treatment was performed using a high frequency generator RFG-500 manufactured by Yamato Scientific Co., Ltd. and a processing chamber PC-103.

The conditions for the oxygen plasma treatment are as follows:
ml / min, output 120 W, processing time 1 minute.

In this first deterioration promotion step, oxygen plasma was applied to the test piece to increase the oxidation of the coating film on the test piece and accelerate the deterioration of the coating film in a short time.

(1) Second Degradation Acceleration Step In the second degradation acceleration step 1, a test piece and a hydrogen peroxide solution were placed in a quartz glass container (diameter 43 mm, height 200 m) prepared in advance.
m, glass thickness 2 mm) and the test piece is immersed in a hydrogen peroxide solution. The hydrogen peroxide solution was prepared by diluting a hydrogen peroxide solution (30% by weight, a reagent manufactured by Wako Pure Chemical Industries) with ion-exchanged water to a concentration of 3% by weight. Held.

In this state, a test piece in a hydrogen peroxide solution was irradiated with light (ultraviolet light) from an ultraviolet fluorescent lamp through the wall surface of the quartz glass container at 50 W / m ² for 5 hours.

(Second Deterioration Acceleration Step 2) Subsequently, in the second deterioration acceleration step 2, the hydrogen peroxide solution in the quartz glass container was replaced with ion exchange water, and the test piece was immersed in ion exchange water. State. The ion-exchanged water was maintained at a temperature of 60 ° C. by a temperature controller.

In this state, the light from the ultraviolet fluorescent lamp was transmitted through the wall of the quartz glass container to the test piece in the ion-exchanged water in the same manner as described above, and then controlled to 50 W / m ² for 5 hours. Irradiated.

At the end of the second deterioration accelerating step in this way, the test piece in the quartz glass container was taken out and measured for its 60 degree gloss, which was used as an index of the degree of deterioration.

(Measurement of 60-degree gloss) The 60-degree gloss was measured with a gloss meter GM-3D (manufactured by Murakami Color Research Laboratory).

The change in 60-degree gloss with respect to the cumulative processing time of the test piece subjected to the accelerated exposure test method of Example 1 is shown in FIG.
And 94 immediately after preparation (indicating an unpromoted exposure state, at a cumulative treatment time of 0 h).
After the above cycle was repeated six times (accumulated processing time 60 h indicating the accelerated exposure state), it was 20.

Therefore, according to the accelerated exposure test method of Example 1, the change in the 60-degree gloss of the coating film when the above-mentioned conventional accelerated exposure test apparatus (Sunshine Weathermeter (manufactured by Suga Test Instruments)) was used ( The test period (time) can be greatly reduced as compared with FIG. 7).

Further, by following the accelerated exposure test method of Example 1, by performing the first deterioration accelerating step and the second deterioration accelerating steps 1 and 2, the decrease in gloss due to the deterioration of the coating film of the test piece can be reduced. It was confirmed that the effect of accelerating was obtained by performing the accelerated exposure test method of Comparative Example 1 and comparing the result.

(Comparative Example 1) In Comparative Example 1, the same test piece as in Example 1 was used, and the test piece was cycled under the same conditions as in Example 1 except that the first deterioration promotion step was omitted. Was repeated six times.

The change in the 60-degree gloss of the test piece subjected to the accelerated exposure test method of Comparative Example 1 with respect to the cumulative processing time is shown in FIG.
And 94 immediately after preparation (indicating an unpromoted exposure state, at a cumulative treatment time of 0 h).
After the above cycle was repeated six times (accumulated processing time 60 h indicating the accelerated exposure state), it was 71.

In the case of the first embodiment, the 60-degree gloss 71 of the comparative example 1 at the cumulative processing time of 60 h (see FIG. 2).
Estimating the cumulative processing time approximately equivalent to
Since the gloss 67 was obtained at the position of the accumulated processing time of 20 h (see FIG. 1), it was confirmed that the gloss could be reduced to about 1/3 as compared with Comparative Example 1.

[0056]

Example 2 The accelerated exposure test method of Example 2 uses a hydrogen peroxide solution used in the second deterioration accelerating step instead of using a 3% by weight solution prepared by diluting with ion-exchanged water in advance. The use of a solution prepared by diluting with ion-exchanged water at a concentration of 0.1% by weight, the irradiation of a test piece in a hydrogen peroxide solution with ultraviolet rays for 10 hours, and the treatment of light irradiation in the ion-exchanged water were omitted. The procedure was the same as the accelerated exposure test method of Example 1 except that the test was conducted.

FIG. 3 shows the change in gloss at 60 degrees with respect to the cumulative processing time of the test piece subjected to the accelerated exposure test method of Example 2.
And 94 immediately after preparation (indicating an unpromoted exposure state, at a cumulative treatment time of 0 h).
After the above cycle was repeated six times (accumulated processing time 60h indicating the accelerated exposure state), it was 43.

Therefore, according to the accelerated exposure test method of Example 2, the change in the 60-degree gloss of the coating film when the above-mentioned conventional accelerated exposure test apparatus (Sunshine Weather Meter (manufactured by Suga Test Machine)) was used ( The test period (time) can be greatly reduced as compared with FIG. 7).

In the following, according to the accelerated exposure test method of Example 2, by performing the first deterioration promotion step and the second deterioration promotion step, an effect of accelerating the reduction in gloss accompanying the deterioration of the coating film of the test piece can be obtained. This was confirmed by applying the accelerated exposure test method of Comparative Example 2 and comparing the results.

Comparative Example 2 In Comparative Example 2, the same test piece as in Example 2 was used, and the cycle was the same as in Example 2 except that the first deterioration accelerating step was omitted. It was repeated six times.

The change in the 60-degree gloss of the test piece subjected to the accelerated exposure test method of Comparative Example 2 with respect to the cumulative processing time is shown in FIG.
And 94 immediately after preparation (indicating an unpromoted exposure state, at a cumulative treatment time of 0 h).
After the cycle is repeated 6 times (indicating accelerated exposure,
It was 84 in the cumulative processing time 60h position).

In the case of the second embodiment, the accumulated processing time of 20 hours is equivalent to the position shown in FIG.
Since the h position was reached and the cycle was repeated twice, it was confirmed that the time could be significantly reduced as compared with Comparative Example 2.

[0063]

Example 3 In the accelerated exposure test method of Example 3, instead of applying a top coat consisting of a white solid in Example 1 as a test piece, a silver base and a clear paint were applied.

In the accelerated exposure test method of Example 3, the test piece was first subjected to the second degradation promoting step 1, followed by the first degradation promoting step, and further to the second degradation promoting step 2. After that, measuring the 60 degree gloss as one cycle,
The above cycle is repeated 10 times.

(Second Deterioration Acceleration Step 1) In the second deterioration acceleration step 1, the test piece was immersed in 60 ° C. hot water for 4 hours.

(First Degradation Acceleration Step) The first degradation acceleration step is the same as the first degradation acceleration step in Example 1 except that the low-temperature oxygen plasma treatment time is set to 2 minutes.

(Second Deterioration Acceleration Step 2) In the second degradation acceleration step 2, about 2 ml of ion-exchanged water was placed in a quartz glass container together with a test piece and sealed, kept at 60 ° C., and the inside of the quartz glass container was kept. High humidity (humidity 80% to 100%) was applied, and the ultraviolet rays were irradiated under the same conditions as in the second deterioration promoting step in Example 1.
Irradiated for hours.

The change in the 60 degree gloss of the coating film of the test piece is shown in FIG.
The number was 98 immediately after the preparation (indicating the unaccelerated exposure state, that is, at the treatment cycle number 0 position), but was 68 after repeating the cycle 10 times.

Therefore, according to the accelerated exposure test method of Example 3, the change in the 60-degree gloss of the coating film when the above-mentioned conventional accelerated exposure test apparatus (Sunshine Weathermeter (manufactured by Suga Test Instruments)) was used ( The test period (time) can be greatly reduced as compared with FIG. 7).

Further, in the following, according to the accelerated exposure test method of Example 3, performing the first deterioration promotion step and the second deterioration promotion step has the effect of promoting the reduction in gloss accompanying the deterioration of the coating film of the test piece. It was confirmed by performing the accelerated exposure test method of Comparative Example 3 and comparing the results.

Comparative Example 3 In Comparative Example 3, the same test piece as in Example 3 was used, and the cycle was the same as that in Example 3 except that the first deterioration accelerating step was omitted. Repeated 10 times.

As a result, the gloss of the coating film of the test piece subjected to the accelerated exposure test method of Comparative Example 3 did not show a significant decrease.

This is because, under the processing conditions of Comparative Example 3, the processing must be repeated a predetermined number of times in order to cause a significant decrease in the 60-degree gloss due to the durability deterioration of the test piece. means.

Accordingly, in the case of the third embodiment, by comparing with the case of the comparative example 3, it is possible to cause deterioration in a short time by combining the oxygen plasma treatment and the other durability deterioration treatment. It turns out to be.

[0075]

Embodiment 4 An accelerated exposure test apparatus according to the present invention will be described as Embodiment 4 with reference to FIG.

The accelerated exposure test apparatus 1 of the fourth embodiment will be described as applied to a case where the test piece 9 is applied.

The accelerated exposure test apparatus 1 includes a container 2, a temperature control unit 3, an oxygen plasma generation unit 4, a gas supply unit 5,
The apparatus includes a liquid supply unit 6, a light irradiation unit 7, and a discharge unit 8.

The container 2 is a stainless steel box fixed and held in a not-shown fixed position, and has a wall portion 2 having a predetermined strength.
0, an internal space 21 defined by the wall 20 and capable of being cut off and communicating with the outside and accommodating the test piece 9 so as to be able to be taken in and out, and formed in a part of the wall 20 and facing the light irradiation section 7. A light irradiation window 22 made of quartz glass is provided at the position.

The temperature control section 3 brings the gas (air, oxygen) or liquid (water, an aqueous solution of an oxidizing agent such as hydrogen peroxide, ion-exchanged water, etc.) contained in the internal space 21 of the container 2 to a predetermined temperature. A heater (not shown) installed on the outer periphery of the container 2 so as to be able to heat the internal space 21 so as to be held, and a hollow for flowing a heat medium such as hot water, hot air, or heated steam installed on the outer periphery of the container 2 For example, a temperature control device having a section can be used.

The oxygen plasma generator 4 can use a conventional oxygen plasma generator, has a function of supplying the generated oxygen plasma to the internal space 21 of the container 2, and has an opening / closing valve 4.
0 and can be shut off and communicate with the front interior space 21.

The gas supply section 5 has a function of supplying oxygen and the like to the internal space 21 of the container 2 and has an opening / closing valve 50, and can shut off and communicate with the front internal space 21. Note that, as the gas supply unit 5, a general oxygen cylinder filled with oxygen or the like can be used.

The liquid supply section 6 has a function of supplying water or hydrogen peroxide to the internal space 21 of the container 2 and has an opening / closing valve 60, and can shut off and communicate with the front internal space 21.

The liquid supply unit 6 manually injects a predetermined liquid into the container 2 from a sealable opening (not shown) provided in the wall of the container 2 above the position where the test piece 9 is installed. It may be of the type.

The light irradiating section 7 has a light source 70.
In order to degrade the test piece 9 in the internal space 21 of the container 2 with light from the container 2, light is irradiated through the light irradiation window 22 of the container 2. As the light source 70, an ultraviolet fluorescent lamp can be used.

The discharge portion 8 communicates with a not-shown pressure reducing pump or discharge pump, a discharge passage, and the like, and has an opening / closing valve 80 so as to be able to shut off and communicate with the front internal space 21.

The accelerated exposure test apparatus 1 of Embodiment 4 configured as described above can perform the first deterioration promotion step and the second deterioration promotion step in the accelerated exposure test methods of Embodiments 1 to 3. .

That is, when the accelerated exposure test apparatus 1 is used to perform the first degradation promotion step and the second degradation promotion step,
First, the test piece 9 is accommodated in the internal space 21 of the container 2 and fixedly held (set) at a predetermined position. Then, the internal space 21 of the container 2 is kept in a state where the parts other than the discharge part 8 and the oxygen plasma generation part 4 are shut off, and the pressure is reduced through the discharge part 8 to be maintained at a predetermined low pressure.

Next, oxygen plasma is supplied from the oxygen plasma generating section 4 to the internal space 21 in this state, and the test piece 9 is exposed to oxygen plasma. The conditions for exposing the test piece 9 to the oxygen plasma are the same as those in Example 1 (oxygen flow rate 40 ml / min, output 120 W, processing time 1 minute).

After that, the process proceeds to the second deterioration accelerating step, and preparations are made prior to this. That is, the internal space 21 of the container 2 is shut off from the discharge unit 8, the oxygen plasma generation unit 4, and the gas supply unit 5, and is kept in a state of communicating with the liquid supply unit 6.

The liquid supply unit 6 is provided in the internal space 21.
To hydrogen peroxide solution [(concentration 3% by weight prepared by diluting (30% by weight, Wako Pure Chemical Reagent)] with ion-exchanged water]
Is injected to the liquid level at which the test piece 9 in the internal space 21 is immersed. On the other hand, the temperature of the hydrogen peroxide solution is maintained at 40 ° C. by the temperature control unit 3.

In this state, the test piece 9 in the hydrogen peroxide solution is irradiated with ultraviolet light from the light irradiation section 7 through the light irradiation window 22 for 5 hours (the intensity of the ultraviolet light is transmitted through the light irradiation window 22, 5
0 W / m ² ).

Thereafter, the second deterioration promoting step is further advanced, and preparations are made prior to this. That is, as the preparation, first, the discharge unit 8 is operated to communicate the internal space 21 of the container 2 with the outside, and the hydrogen peroxide in the internal space 21 is discharged.

Then, the internal space 21 and the discharge section 8 are shut off, and the internal space 21 communicates with the liquid supply section 6 so that the ion exchange water immerses the test piece 9 in the internal space 21 from the liquid supply section 6. It is injected to the face position. On the other hand, the temperature of the ion-exchanged water is maintained at 60 ° C. by the temperature control unit 3.

In this state, the ultraviolet light from the light irradiation section 7 is irradiated to the ion-exchanged water and the test piece 9 through the light irradiation window 22 for 5 hours.
It is controlled to be 50 W / m ² ).

Next, when the second deterioration promoting step is completed, the test piece 9 in the internal space 21 of the container 2 is taken out, and its 60-degree gloss is measured, which is used as an index of the degree of progress of deterioration.

As described above, the accelerated exposure test apparatus 1 of the fourth embodiment
According to the method described above, a plurality of different steps (the first deterioration promotion step and the second deterioration deterioration step) in the accelerated exposure test methods of the first to third embodiments are applied to the test piece 9 housed and set in the internal space 21 of the container 2. (Acceleration step) can be performed by one apparatus.

Further, when a control system for automatically operating a plurality of steps in a plurality of steps as one cycle is incorporated, the accelerated exposure test method can be performed more efficiently.

[0098]

(1) According to the accelerated exposure test method of the present invention, the test piece is repeatedly subjected to the first degradation promotion step and the second degradation promotion step at least once, respectively, so that the specimen can be exposed to the natural environment. The same conditions as those used for a long time can be reproduced in a shorter time than the conventional accelerated exposure test method.

That is, the surface of the test piece subjected to the first deterioration accelerating step undergoes oxidative deterioration in a short period of time due to the action of oxygen plasma.

The surface of the test piece is subjected to the action of water and either one of oxygen and light, or the action of oxygen and light together with the action of water by the second deterioration promoting step performed separately from the first deterioration promoting step. Both effects can promote deterioration under almost the same conditions as in a natural environment. Either the first deterioration promotion step or the second deterioration promotion step may be performed first. (2) According to the accelerated exposure test apparatus of the present invention, the test piece is accommodated in the inner space of one container, and the first degradation promotion step and the second degradation promotion step of the accelerated exposure test method are performed. Can be repeated one or more times.

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between a cumulative processing time and a change in 60-degree gloss in a test piece subjected to the accelerated exposure test method of Example 1.

FIG. 2 is a graph showing the relationship between the cumulative processing time and the change in 60-degree gloss of a test piece subjected to the accelerated exposure test method of Comparative Example 1.

FIG. 3 is a diagram showing a relationship between a cumulative treatment time and a change in 60-degree gloss in a test piece subjected to the accelerated exposure test method of Example 2.

FIG. 4 is a diagram showing a relationship between a cumulative treatment time and a change in 60-degree gloss in a test piece subjected to the accelerated exposure test method of Comparative Example 2.

FIG. 5 is a diagram showing the relationship between the number of treatment cycles and the change in 60-degree gloss in a test piece subjected to the accelerated exposure test method of Example 3.

FIG. 6 is a side view showing a schematic cross section of a main part of an accelerated exposure test apparatus according to a fourth embodiment.

FIG. 7 is a diagram showing the relationship between the processing time and the change in 60-degree gloss of a test piece subjected to an accelerated exposure test method using a conventional accelerated exposure test apparatus [Sunshine Weathermeter (manufactured by Suga Test Instruments)].

[Explanation of symbols]

1. Accelerated exposure test equipment 2. Container
3: Temperature control unit 4: Oxygen plasma generation unit 5: Gas supply unit
6 liquid supply unit 7 light irradiation unit 8 discharge unit
9 ... Test piece

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Kazuyuki Tachi 41-Fa. EA05 EA06 EB07 EC01 EC06

Claims (5)

[Claims] 1. A first deterioration promoting step in which oxygen plasma is caused to act on a surface of a test piece to promote oxidative deterioration of the surface, and one of water, light and oxygen containing water among the surface of the test piece is included. A second degradation promoting step of promoting the hydrolysis degradation or both the hydrolysis degradation and the oxidative degradation of the surface by acting on the above, wherein the first degradation promotion step and the second degradation promotion step are at least respectively performed. An accelerated exposure test method characterized by being repeated one or more times. 2. The accelerated exposure test method according to claim 1, wherein the second deterioration accelerating step includes irradiating the surface of the test piece with light in water or in an atmosphere having a relative humidity of 20% or more. 3. The accelerated exposure test method according to claim 1, wherein said second deterioration accelerating step includes irradiating said surface of said test piece with light in an aqueous solution containing an oxidizing agent. 4. The second deterioration promoting step includes irradiating the surface of the test piece with light in an aqueous solution containing 0.001% to 60% by weight of hydrogen peroxide, 3. The accelerated exposure test method according to claim 2, comprising irradiating the surface with light in water or an atmosphere having a relative humidity of 20% or more. 5. A container provided with an internal space capable of accommodating and sealing a test piece, an oxygen plasma generating / supplying unit for supplying oxygen plasma to the internal space, and a gas or a gas containing water vapor in the internal space. A gas supply unit that supplies a gas containing both water vapor and oxygen, a light irradiation unit that irradiates light to the surface of the test piece, and a discharge unit that discharges a used substance from the internal space. An accelerated exposure test device characterized by the following.