Method for evaluating ultraviolet durability of building material

Abstract

To provide a new evaluation method capable of easily evaluating durability of a building material against ultraviolet rays in a short time without using a special device such as a weathering meter.SOLUTION: The ultraviolet durability of the building material is evaluated from the surface state of the building material irradiated with ultraviolet rays by irradiating the building material with the ultraviolet rays of an ultraviolet sterilization lamp for an irradiation time of 0.5 to 8 hours (steps 301, 302) (step 303).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a technique for evaluating the effects of ultraviolet light on building materials. [Background technology]

[0002] Building materials deteriorate when exposed to sunlight for long periods of time, so a certain level of durability is required. Outdoor exposure tests are known as the basic testing method for evaluating the weather resistance of building materials to sunlight, but they take as long as 5 to 6 years. Therefore, accelerated weathering tests are used, which can predict deterioration in a shorter period of time. Accelerated weathering tests use a xenon weathering meter or sunshine weathering meter to irradiate test specimens of building materials with light that has a spectral distribution similar to that of sunlight reaching the earth's surface, thereby accelerating deterioration and shortening the time required for deterioration evaluation.

[0003] Although the weathering meter described above uses a xenon arc lamp or a sunshine carbon arc lamp as a light source, the use of ultraviolet fluorescent lamps for accelerated exposure tests has also been proposed. For example, Patent Document 1 discloses an ultraviolet fluorescent lamp whose spectral radiation characteristics have a peak at wavelengths of 305 nm to 325 nm, thereby making the spectral radiation characteristics around a wavelength of 310 nm closer to those of sunlight reaching the earth's surface. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 63-216263 Summary of the Invention [Problem to be solved by the invention]

[0005] However, even in accelerated weathering tests, evaluation of interior materials requires continuous exposure for approximately 300 to 500 hours, and for exterior materials, it requires over 2,000 hours, and there is a need to further shorten the test period. Furthermore, the equipment used in accelerated weathering tests is complex, requiring auxiliary equipment for circulating pure water cooling water, and is generally expensive. In addition, the size of the test specimen in the weathering meter mentioned above is limited to 150 x 75 mm, and tests cannot be performed on other sizes.

[0006] The ultraviolet fluorescent lamp disclosed in Patent Document 1 has special spectral radiation characteristics that have a peak at wavelengths of 305 nm to 325 nm and attenuate radiation energy at wavelengths below 300 nm. For this reason, readily available commercial products such as health-ray lamps cannot be used. Using such ultraviolet fluorescent lamps in an accelerated exposure tester would not only increase the complexity of the equipment mentioned above, but would also increase costs.

[0007] The present invention has been devised in view of the above-mentioned circumstances, and an object of the present invention is to provide a novel evaluation method that can easily evaluate the durability of building materials against ultraviolet rays in a short period of time without using a special device such as a weathering meter.

[0008] In the course of intensive research to achieve the above object, the inventors discovered that it is possible to evaluate the quality of building materials in a much shorter time than conventional testing by irradiating the materials with ultraviolet light from a disinfecting ultraviolet device equipped with an ultraviolet germicidal lamp installed in beauty salons, barber shops, hospitals, etc. The present invention is based on this finding. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, one aspect of the present invention provides a method for evaluating ultraviolet durability, which comprises irradiating a building material with ultraviolet light from an ultraviolet germicidal lamp for an irradiation time of 0.5 hours to 8 hours, and evaluating the ultraviolet durability of the building material from the surface condition of the building material irradiated with the ultraviolet light. According to one aspect of the present invention, the building materials can be placed in a disinfecting ultraviolet device equipped with the ultraviolet germicidal lamp, and the ultraviolet irradiation time of the disinfecting ultraviolet device can be set to between 0.5 hours and 8 hours. According to one aspect of the present invention, the disinfection ultraviolet device has a luminous intensity of 85 μW / cm 2 An ultraviolet sterilizer capable of irradiating the above ultraviolet rays for 20 minutes or more can be used. According to one aspect of the present invention, the irradiation time of the ultraviolet light may be set to 6 hours or less. According to one aspect of the present invention, the building material may include any one of paint, mortar, wallpaper, sealant, plastering material, flooring material, and sheet material. According to one aspect of the present invention, it is desirable to irradiate the building material with ultraviolet light after drying the building material. According to one aspect of the present invention, the building material can be irradiated with ultraviolet light after being laminated on a base material. According to one aspect of the present invention, the surface condition of the building material irradiated with the ultraviolet light can be observed using a precision observation device. [Effects of the Invention]

[0010] According to one aspect of the present invention, by using an ultraviolet germicidal lamp, the time required for evaluating ultraviolet durability can be significantly reduced compared to xenon weathering meters or sunshine weathering meters, and the lamp is easy to obtain and can achieve low costs. According to one aspect of the present invention, by using an ultraviolet disinfection device equipped with an ultraviolet germicidal lamp, the time required for ultraviolet durability evaluation can be significantly reduced, and it is easy to obtain and low cost can be achieved. According to one aspect of the present invention, 85 μW / cm 2By using an ultraviolet sterilizer capable of irradiating the above ultraviolet light for 20 minutes or more, it is possible to achieve easy availability and low cost. In other words, such ultraviolet sterilizers are used in beauty salons and barber shops, and their performance conforms to the sterilization method stipulated in Article 25, Paragraph 2, Item (i) of the Enforcement Regulations of the Barbers Act / Cosmetologists Act, and are standardized nationwide. Therefore, they are available inexpensively at any medical equipment retailer. Furthermore, they offer the flexibility to evaluate any test specimen as long as it is the right size and shape to fit into the ultraviolet sterilizer, and have the advantage of not being restricted by the size or shape of conventional weathering meters. According to one aspect of the present invention, evaluation is possible even if the ultraviolet irradiation time is within 6 hours, and the time required for evaluation of ultraviolet durability can be significantly reduced. According to one aspect of the present invention, the ultraviolet durability of interior and exterior materials can be evaluated in a short period of time. According to one aspect of the present invention, ultraviolet durability evaluation can be carried out in a short time even for building materials that contain a large amount of moisture or organic solvents. According to one aspect of the present invention, ultraviolet resistance evaluation can be performed in the form in which a building material is actually used, that is, laminated on a base material, making it possible to perform evaluation that is in line with actual use. According to one aspect of the present invention, the surface condition of a building material is observed using a precision observation device, which makes it possible to observe minute changes that cannot be detected by visual observation and to determine ultraviolet degradation at an early stage. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic perspective view showing an example of a disinfection ultraviolet device for carrying out a durability evaluation method according to one embodiment of the present invention. [Figure 2] FIG. 2 is a side cross-sectional view schematically showing the internal configuration of the disinfecting ultraviolet device illustrated in FIG. 1. [Figure 3] 3 is a flowchart showing an example of an operation procedure of the durability evaluation method according to the present embodiment. [Figure 4] 1 is a diagram illustrating an example of a change in the surface state of paint 1 irradiated with ultraviolet light by an ultraviolet disinfection device according to the present embodiment. [Figure 5]1 is a diagram illustrating an example of a change in the surface state of paint 3 irradiated with ultraviolet light by the disinfection ultraviolet device of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the components of the ultraviolet disinfection device, their shapes, dimensions, dimensional ratios, and arrangements described in the following embodiments are merely examples for explaining the present embodiments, and are not intended to limit the technical scope of the present invention to those alone.

[0013] <Ultraviolet light equipment for disinfection> 1 and 2, housing 101 of ultraviolet disinfection device 100 has internal space 102, within which ultraviolet germicidal lamps 103 and shelves 104 are arranged at a predetermined distance. Note that multiple ultraviolet germicidal lamps 103 may be arranged. Building material 200, which serves as a test specimen, is placed on shelf 104. The test specimen may have any shape and size as long as it can be placed on shelf 104, and small test pieces as small as about 10 mm square can be tested. Therefore, it is much more flexible and easier to handle than a weathering meter, which has a fixed test specimen size.

[0014] The building material 200 is mortar, concrete, paint, wallpaper, sealant, plastering material, flooring material, wood, plywood, sheet material, etc. However, materials that contain a lot of water or organic solvents tend to become unstable in shape, so it is preferable to use materials that have had the water or solvent dried.

[0015] The housing 101 is provided with an acrylic door 105 that can be opened and closed, allowing the construction material 200 to be easily taken in and out. The ultraviolet germicidal lamp 103 can be turned on with the acrylic door 105 closed, and it is desirable that the lamp be automatically turned off when the acrylic door 105 is opened while the lamp is on. When the ultraviolet germicidal lamp 103 is turned on, ultraviolet light L having germicidal power is emitted. UVThe ultraviolet light is irradiated onto the building materials 200 on the shelf 104 at a predetermined intensity, which will be described later. The desired irradiation time can be set using the operation unit 106. The power source for the ultraviolet disinfection device 100 can be obtained from a commercial AC power source. The operation unit 106 is also provided with a power switch as well as a timer for setting the irradiation time, but details thereof will be omitted.

[0016] The ultraviolet disinfection device 100 used in this embodiment can be a stabiliser (ultraviolet steriliser) installed in a beauty salon, a barber shop, a hospital, etc. This stabiliser has performance conforming to the disinfection method stipulated in Article 25, Paragraph 2, Item (i) of the Enforcement Regulations of the Barbers Act / Cosmetologists Act, and has an ultraviolet ray output of 85 μW / cm 2 The ultraviolet light having the above sterilizing power can be irradiated onto the building material 200 for 20 minutes or more. In addition, since the performance is regulated by law, the disinfection ultraviolet device 100 that meets the national standard can be easily obtained at medical equipment stores, etc.

[0017] The ultraviolet germicidal lamp 103 emits ultraviolet light in a wavelength band that has a germicidal effect. It is known that the germicidal power of ultraviolet light is strongest around a wavelength of 260 nm. Here, as an example, an ultraviolet germicidal lamp 103 capable of emitting ultraviolet light in a wavelength band of 253±5 nm is used. Although this wavelength differs from the ultraviolet lamps used in conventional accelerated exposure tests, which are closer to the wavelength of sunlight, it is effective as a weather resistance test aimed at a simple evaluation that can confirm the effects of ultraviolet light in sunlight. Therefore, by preparing the disinfection ultraviolet device 100, the building material 200 can be exposed to ultraviolet light with a wavelength of 253±5 nm and an intensity of 85 μW / cm. 2 More than 10 ... UV The ultraviolet ray durability evaluation method according to this embodiment using the ultraviolet ray disinfection device 100 will be described below.

[0018] <Ultraviolet light irradiation procedure> 3, the acrylic door 105 of the ultraviolet disinfection device 100 is opened and the building material 200 as a test specimen is placed on the shelf 104 (step 301). Next, the ultraviolet irradiation time is set to between 30 minutes and 8 hours using the operation unit 106, and irradiation is started. As a result, the building material 200 on the shelf 105 is irradiated with ultraviolet light having a wavelength of 253±5 nm and an intensity of 85 μW / cm. 2 More than 10 ... UV The ultraviolet light is continuously irradiated for a preset time (step 302). The ultraviolet light irradiation time may be set to a time at which changes in the surface condition of the building material 200 can be observed visually or with precision observation equipment, as will be described later. By using the ultraviolet germicidal lamp 103, changes in the surface condition of the building material 200 can be observed with ultraviolet light irradiation for as short as about 0.5 hours or as long as about 8 hours.

[0019] In this way, UV-L UV The change in the surface condition of the building material 200 due to the ultraviolet light is observed, and the durability of the building material 200 is evaluated (step 303). UV Continuous irradiation of the building material 200 causes peeling or cracking on the surface, and the degree of peeling or cracking can be evaluated by visual inspection, or if not visual inspection, by observation using precision observation equipment such as a microscope. Examples of precision observation equipment that can be used include magnifying glasses known as loupes, optical microscopes, scanning electron microscopes (SEMs), transmission electron microscopes (TEMs), and electron spectroscopic analyzers (ESCAs). Post-irradiation observation can be performed by visual observation as well as various other measurements such as penetration, color difference, and weight measurement. Even if no changes in the surface condition are detected visually, microscopic observation can be performed using a scanning electron microscope, enabling early detection of UV degradation. Examples of the present invention are described below.

[0020] In addition, as a method for determining ultraviolet degradation of building materials, a plurality of different building materials 200 are subjected to ultraviolet L under the same conditions. UVBy comparing the surface conditions through continuous irradiation of UV light, a simple evaluation can be performed to determine relative superiority or inferiority. In addition, by evaluating UV degradation in combination with a reference material, it is also possible to easily determine superiority or inferiority based on differences in surface condition. Furthermore, by setting multiple evaluation stages based on the degree of surface degradation in advance, it is possible to perform a simple evaluation by assigning surface conditions due to UV degradation to similar stages.

[0021] <Example> As a disinfection ultraviolet device 100, the intensity is 85μW / cm 2 The stabiliser (FV-209V; manufactured by Fifty Visionary Co., Ltd.) was used, which can continuously irradiate the above ultraviolet light for 20 minutes or more. The dimensions of the internal space 102 (inside the cabinet) of the stabiliser were 310 mm in width, 160 mm in depth, and 190 mm in height, and ultraviolet light L with a wavelength of 253 ± 5 nm was irradiated. UV It is equipped with an ultraviolet germicidal lamp that irradiates

[0022] In the following examples, a synthetic resin emulsion paint was used as the measurement target (building material 200), and an aluminum plate 2 mm thick and 50 x 50 mm in size was used as the base material. Six types of paints 1 to 6 shown in Table 1 were used as the synthetic resin emulsion paints, and 10 parts by weight of decorative aggregate was added to each paint and applied to the base material to form test specimens. Paints 1 to 6 are each a different product name and are manufactured by a different company.

[0023] [Table 1]

[0024] Test specimens of paints 1 to 6 were placed on the shelf 105 of the disinfection ultraviolet device 100 (Stearizer FV-209V), and the condition of the paint surface was visually observed 3 hours and 6 hours after ultraviolet irradiation. The results are shown in Table 2.

[0025] [Table 2]

[0026] Similarly, the condition of each paint surface was observed 3 and 6 hours after UV irradiation using an electron microscope. Here, observations were made using a tabletop scanning electron microscope at 100x magnification. The results are shown in Table 3.

[0027] [Table 3]

[0028] As can be seen from Tables 2 and 3 above, cracks were observed under a microscope even in paints 1 and 2, where no changes were observed visually. Furthermore, it became clear that the cause of the peeling observed visually in paints 3 to 6 was cracks in the paint film. As shown in Figure 4, in the case of paint 1, after 6 hours of irradiation, a clear change was observed in the paint film on the aggregate using an electron microscope. Furthermore, as shown in Figure 5, in the case of paint 3, cracks were observed under an electron microscope after 3 hours of irradiation.

[0029] As mentioned above, in this example, observable changes in the coating surface occurred after about six hours of UV irradiation. If a similar test were to be carried out using a xenon weather meter, it would likely require more than 300 hours of exposure, so the present invention makes it possible to evaluate the quality of paints in a much shorter time.

[0030] The present invention has been specifically described above based on its embodiments, but it goes without saying that the present invention is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit of the present invention. [Explanation of symbols]

[0031] 100 Ultraviolet light equipment for disinfection 101 Case 102 Interior Space 103 Ultraviolet germicidal lamp 104 Shelf 105 Acrylic Door 106 Operation section

Claims

1. A method for evaluating ultraviolet durability, comprising irradiating a building material with ultraviolet light from an ultraviolet germicidal lamp for an irradiation time of 0.5 hours or more and 8 hours or less, and evaluating the ultraviolet durability of the building material from the surface condition of the building material irradiated with the ultraviolet light.

2. The ultraviolet durability evaluation method according to claim 1, characterized in that the building material is placed in a disinfecting ultraviolet device equipped with the ultraviolet germicidal lamp, and the ultraviolet irradiation time of the disinfecting ultraviolet device is set to be not less than 0.5 hours and not more than 8 hours.

3. The disinfection ultraviolet device has a wavelength of 85 μW / cm ２ The ultraviolet durability evaluation method according to claim 2, characterized in that an ultraviolet sterilizer capable of irradiating the ultraviolet rays for 20 minutes or more is used.

4. 4. The method for evaluating durability to ultraviolet rays according to claim 1, wherein the ultraviolet irradiation time is 6 hours or less.

5. 4. The ultraviolet durability evaluation method according to claim 1, wherein the building material includes any one of paint, mortar, wallpaper, sealant, plastering material, flooring material, and sheet material.

6. 4. The ultraviolet durability evaluation method according to claim 1, wherein the building material is irradiated with the ultraviolet rays after being dried.

7. 4. The ultraviolet resistance evaluation method according to claim 1, wherein the building material is laminated on a base material and then irradiated with the ultraviolet rays.

8. The ultraviolet durability evaluation method according to any one of claims 1 to 3, characterized in that the surface condition of the building material irradiated with the ultraviolet rays is observed using a precision observation device.

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