JP2002310953A - Method and apparatus for measuring the amount of adhesion of surface treatment film - Google Patents

Abstract

(57) [Summary] [Problem] To accurately measure the amount of coating of a product formed with a coating containing a light element, which is difficult to measure by X-ray fluorescence, even in air.
In addition, the measurement can be performed in a short time. SOLUTION: While transporting a product (metal plate) M on which a film is formed by a surface treatment, the adhesion amount of the film is measured based on fluorescent X-rays generated when the surface of the product is irradiated with X-rays. An X-ray source 12 for irradiating the X-ray, and a measuring head 16 having a space portion 14 surrounding a fluorescent X-ray generation site on the product surface. A moving device for moving at the same speed as the transfer speed, and a vacuum pump 20 for bringing the measuring head 16 into close contact with the surface of the product and moving the space 14 to a vacuum during the movement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment film such as a chemical conversion film or an organic-inorganic composite film formed on the surface of a product in a transporting state, and particularly, it is difficult to measure fluorescent X-rays in the air. The present invention relates to a method and an apparatus for measuring the amount of adhesion of a surface treatment film, which is preferably applied when measuring the adhesion amount of a surface treatment film containing a light element as a main constituent component by a fluorescent X-ray method.

[0002]

2. Description of the Related Art The amount of a surface-treated coating such as a chemical conversion coating or an organic-inorganic composite coating formed by surface-treating a product is as follows.
It is an important index that directly affects the properties of various products such as corrosion resistance, chemical conversion, conductivity, and weldability. Therefore, from the viewpoint of product quality control, it is important that the amount of coating film be strictly controlled within a predetermined range so as to exhibit the above characteristics. Therefore, it is conventionally possible to measure the adhesion amount of the surface treatment film using a measuring device using infrared absorption spectroscopy or X-ray fluorescence analysis, and to control the operating conditions of the surface treatment process based on the measurement result. Is being done.

[0003] The infrared absorption spectroscopy is often used when the surface treatment film is formed only of an organic substance such as a resin. In this method, a specific bond in a resin, for example, a vibration such as a C—H bond or an O—H bond is detected by infrared absorption spectroscopy, and the amount of adhesion is determined from its intensity. However, in this infrared absorption spectroscopy, when an oxide or hydroxide of a metal element is added to the surface-treated film for the purpose of improving the properties, the infrared absorption spectrum of these compounds is used for measuring the amount of resin adhered. There is a drawback that the measurement accuracy is remarkably reduced because the used infrared absorption spectrum and the absorption wavelength overlap.

On the other hand, the fluorescent X-ray analysis method is effective when a heavy metal element such as chromium is contained in a film such as a chromate surface-treated film. It is also practiced to measure the intensity of fluorescent X-rays emitted from chromium in the coated film and convert it to the amount of adhesion of a chromate surface-treated film to measure the amount of adhesion. However, even in this method, when the amount of the metal element added to the surface-treated film is very small, the fluorescent X-ray intensity is extremely weak, so that sufficient measurement accuracy cannot be obtained. Therefore, it is conceivable to use fluorescent X-rays from light elements such as silicon (Si) and phosphorus (P).

[0005]

However, since the fluorescent X-rays from the light element as described above are greatly attenuated in the atmosphere, the amount of coating of the product in the transport state is reduced by the fluorescent light from the light element. It is very difficult to measure based on X-ray intensity.

[0006] Therefore, conventionally, the adhesion amount of these surface-treated coatings can be determined by taking a sample from the product and using a fluorescent X-ray apparatus capable of measuring in a vacuum using the fluorescent X-rays of light elements in the surface-treated coating. It has been determined by measuring the strength or by chemically dissolving a coating sample collected from the product surface and chemically analyzing a specific element. Since all of these methods require sampling, in the case of continuously mass-produced products, only a very small number of representative values are obtained. In addition, these methods require a long time for the measurement, so that the measurement results cannot be fed back to the operating conditions, so that they cannot be applied to strict control of the adhesion amount of the entire mass-produced product. was there.

[0007] The present invention has been made to solve the above-mentioned conventional problems, and a product having a surface-treated coating containing a light element, which is difficult to measure in the atmosphere under fluorescent X-rays, as a main component, is formed. Even in this case, it is possible to measure the coating amount accurately and in a short time while transporting the product, so that the measurement result can be fed back to the operating conditions. It is an object to provide a method and an apparatus.

[0008]

The structure of the present invention is as follows.

(1) Surface treatment for measuring the adhesion amount of the coating based on the fluorescent X-rays generated when the surface of the product is irradiated with X-rays while transporting the product on which the coating is formed by the surface treatment. A method for measuring the amount of coating applied to a coating, comprising: moving a measuring head having a space surrounding a fluorescent X-ray generation site on a surface of a product together with an X-ray source for irradiating the X-ray at the same speed as a transport speed of the product. While measuring, the measuring head is brought into close contact with the surface of the product, the space is evacuated, and the fluorescent X
A method for measuring the amount of adhesion of a surface-treated film, comprising measuring a line.

(2) The method according to (1), wherein the measuring head is accelerated from an initial position to the same speed as the transport speed, and after returning to the initial position after measuring the fluorescent X-rays. A method for measuring the amount of adhesion of a surface-treated film.

(3) A surface treatment film adhesion amount measuring device for measuring the adhesion amount of the film based on the fluorescent X-rays generated when the surface of the product having the film formed by the surface treatment is irradiated with X-rays. Moving means for moving a measuring head having a space surrounding a fluorescent X-ray generation site on the surface of the product together with the X-ray source for irradiating the X-ray at the same speed as the transport speed of the product; A vacuum suction means for bringing the measuring head into close contact with the product surface and vacuuming the space portion.

(4) Control means for accelerating the measuring head from the initial position to the same speed as the transport speed, measuring the fluorescent X-rays, and returning to the initial position is provided. (3) An apparatus for measuring the adhesion amount of a surface-treated film according to (3).

(5) A seal member for improving airtightness is attached to an opening end located on the product side of the measuring head, wherein the surface treatment film according to (3) or (4) is provided. Adhesion amount measuring device.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an enlarged cross-sectional view schematically showing a main part of an apparatus for measuring the amount of adhesion of a surface treatment film according to an embodiment of the present invention, and FIG. 2 is a schematic view showing a moving state of the measuring apparatus. It is a schematic side view shown.

In this embodiment, as shown in FIG. 2, a band-shaped metal plate (product) M coated (surface treated) by a coating coater (not shown) on the upstream side and having a coating formed thereon is formed. While being transported in the direction of arrow A, the coating amount of the coating is measured from fluorescent X-rays generated when the surface of the metal plate M is irradiated with X-rays by the coating amount measuring device 10.

The measuring apparatus 10 includes a measuring head 16 having a space 14 surrounding a fluorescent X-ray generation site on the surface of the metal plate M together with the X-ray source 12 for irradiating the X-ray.
A moving device (moving means) 18 for moving the measuring head 16 integrally with the device 10 at the same speed as the transfer speed of the metal plate M, and bringing the measuring head 16 moving at the speed into close contact with the product surface. A vacuum pump 20 for evacuating the space 14, and a detector (measuring means) 22 for measuring fluorescent X-rays generated by irradiating X-rays from the X-ray source 12 under vacuum. Here, the vacuum pump 20 is integrally fixed to the main body of the measuring device 10 and the detector 22
Is connected to the space 14 of the measuring head 16 via a spectroscope 26 in which a spectral crystal 24 is disposed at a bent portion of the cylindrical space. Although not shown, a sealing member such as silicone rubber may be provided at the opening end of the measuring head 16 on the metal plate M side to improve the degree of adhesion and airtightness.

The spectroscope 26 and the space 14 are
The vacuum pump 20 is connected to the vacuum pump 20 via a pipe 28A and a pipe 28B, and between the space 14 and one of the pipes 28A and between the space 14 and the spectroscope 26.
Solenoid valves 30A and 30B are provided, respectively, so that gas can flow therethrough. In addition, the vacuum pump 20 is also provided inside the spectroscope 26 together with the space 14.
Is connected, so that a measurable degree of vacuum can be more quickly reached.

In the present embodiment, as described above, when the measuring head 16 is moved by the moving device 18 at the same speed as the transport speed of the metal plate M, as shown in FIG. The measuring device 10 is moved from the initial position by accelerating the measuring device 10 by the moving device 18 to match the conveying speed, and moving the measuring head 16 from the initial position at the same speed.
Is brought into close contact with the metal plate M to evacuate the space portion 14 and measure the fluorescent X-ray under the vacuum. When the measurement is completed, the measuring device 10 is moved in the opposite direction to return to the initial position. The operation control is executed by a control device (not shown). FIG. 3 is a time chart showing the flow of such a single measurement operation.

Therefore, in the present embodiment, the measuring head 16 is moved at the same speed as the transfer speed of the metal plate M by the moving device 18 which can move in the same direction as the transfer direction of the metal plate M. The open end of the measurement head 16 is brought into close contact with the surface, the space 14 inside the measurement head 16 is evacuated by the vacuum pump 20, and fluorescent X-rays can be measured under the vacuum. In addition, by moving the measuring head 16 at the same speed as the metal plate M, the state in which the inside of the apparatus including the space portion 14 is kept at a vacuum can be stably maintained.

Conventionally, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and the space 14 of the measuring head 16 is in the air atmosphere as shown in FIG. The fluorescent X-rays of the element are diffracted by the analyzing crystal 24, and the detector 2
Since it was absorbed by the atmosphere before it reached 2, light elements could not be measured.

On the other hand, in the present embodiment, while moving the measuring apparatus 10, that is, the measuring head 16, the space 14 and the inside of the spectroscope 26 located between the measuring head 16 and the metal plate M are moved. Since the vacuum can be created by the vacuum pump 20, it is possible to prevent the fluorescent X-rays from being absorbed by the atmosphere. As a result, it is possible to accurately measure the coating amount based on the fluorescent X-rays from light elements. It becomes possible.

In particular, the solenoid valve 30B is disposed at the connection between the measuring head 16 and the spectroscope 26, and the inside of the spectroscope 26 is evacuated and held in advance, so that the metal plate M Since the volume of vacuum suction after the head 16 is brought into close contact can be reduced, the inside of the apparatus can more quickly reach a measurable degree of vacuum.

After the measurement is completed, the solenoid valves 30A, 3A
0B is closed, and air is introduced into the space portion 14 of the measuring head 16 from a leak portion (not shown) to return to the atmospheric pressure, whereby the measuring head 16 can be easily separated from the metal plate M and returned to the initial position. By doing so, the next measurement becomes possible. That is, as shown in FIG.
In order to move the measuring head 16 at the same speed as the product M in the transport state, the measuring head 16 is accelerated from an initial position, and when the speed is reached, the state is maintained and measurement (analysis) is performed. By repeating this operation every time the measurement is started, the amount of coating film can be measured periodically at a short cycle of several tens of seconds, and the measurement result can be fed back to the operating conditions.

If the moving device 18 is not provided, the measuring head 16 may be transported to the product itself in order to move the measuring head 16 at the same speed as the metal plate (product) M. In this case, The following problems arise. That is, since the fluorescent X-ray measurement head 16 is transported together with the product, it is necessary to prepare another measurement head for the next measurement. In addition, there are problems such as an adverse effect on product quality due to a load on the product, and vibration of the product causing a failure of the measuring head or the X-ray fluorescence analyzer.

According to this embodiment described in detail above, the surface formed on the metal plate M mainly composed of light elements, which could not be measured by the absorption of fluorescent X-rays by the atmosphere in the past. It is possible to measure the adhesion amount of the treated film in the transported state, making it possible to measure the adhesion amount of chemical conversion coatings and organic-inorganic composite coatings with light elements as the main constituent components in the transported state. Therefore, it is possible to strictly control the amount of the surface treatment film that affects the product quality.

[0027]

FIG. 5 shows a specific result when the present embodiment is applied to the measurement of the adhesion amount of a surface-treated film formed on a long metal plate (coil) manufactured continuously. It is shown in the table in comparison with the method.

In this table, sample A is a metal plate coated with 0.8 g / m ^{2 of} a resin to which 2% by mass of silica (silicon dioxide) is added, and sample B is 0% of a resin to which 20% by mass of a zinc phosphate salt is added. 0.9 g / m ² , which are galvanized steel sheets. Both galvanized coating weights are 2
0 g / m ² .

Conventional Example 1 is an example of measurement using a commercially available X-ray fluorescence analyzer which cannot perform measurement in the transported state. Here, an example using a Rigaku X-ray fluorescence analyzer Simultix3540 is used. Note that Conventional Example 1 is a measurement example using a commercially available fluorescent X-ray apparatus that cannot perform measurement in the transport state,
The certainty of the measured value of the adhesion amount is reliable.
Conventional Example 1 is shown in FIG. 5 for comparison in order to show that the absolute values of the measured adhesion amounts of Examples 1 to 3 are correct. Conventional Example 2 is a measurement example using a plating adhesion meter manufactured by Shimadzu, which measures in a transport state.

Here, the measurement time represents the time during which the fluorescent X-ray intensity is counted. In Examples 1 to 3 and Conventional Example 2, the total measurement time indicates the time required from the start of acceleration to the end of return in FIG. In the first conventional example, it indicates the time from when the operation of setting the sample to the X-ray fluorescence analyzer is started to when the measurement is completed and the sample is completely removed from the X-ray fluorescence analyzer.

Examples 1 to 3 are the results of measurement using the apparatus for measuring the adhesion amount of the surface-treated film according to the present invention.
Here, the results are obtained when the measurement time is changed to 3, 5, and 10 seconds by changing the distance by which the measuring head is moved at the same speed as the product in the transport state.

In Conventional Example 2, the fluorescent X-ray intensities of Si and P were not detected at all, and it was impossible to measure the amount of the surface-treated coating.

On the other hand, in Examples 1 to 3 according to the present invention, the dispersion (σ) of the measured values was 0.05 g / m ^2.
It was confirmed that the adhesion amount of the surface-treated coating can be repeatedly measured in the transport state over the entire length in the length direction of the galvanized steel sheet with the following good measurement accuracy. Further, as can be seen from comparison with Conventional Example 1, Examples 1 to
The absolute value of the measured adhesion amount of No. 3 is sufficiently correct.

Although the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist thereof.

For example, the specific configuration of the apparatus for measuring the amount of coating film is not limited to the one shown in the above embodiment. For example, when the thickness of the metal plate to be measured is as thin as 1 mm or less or when the strength of the metal plate is low, when the inside of the measurement head (space) is evacuated, the metal plate is sucked toward the measurement head and warps. Therefore, there is a possibility of affecting the fluorescent X-ray intensity. Therefore, by providing a means for similarly suctioning the opposite surface of the metal plate to which the measuring head is in close contact with a vacuum,
The warpage of the metal plate may be prevented so that the measurement accuracy is not affected. Further, a similar measuring head may be arranged on the opposite side of the metal plate so that both sides can be measured simultaneously.

As the moving device for moving the measuring head at the same speed as the product being transported, in the above-described embodiment, the case where the measuring head is moved integrally with other device members has been described.
If necessary, a mechanism for transporting components other than the measurement head of the fluorescence analyzer, such as a spectroscope, may be additionally provided.

[0037]

As described above, according to the present invention,
Even for products with a surface-treated coating containing light elements whose main constituent is difficult to measure in the atmosphere, it is difficult to measure fluorescent X-rays. Can be measured. Therefore, the measurement result can be fed back to the operating conditions.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view schematically showing a coating amount measuring apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic side view schematically showing a moving state of the measuring device.

FIG. 3 is a time chart conceptually showing a flow of an adhesion amount measuring operation according to the present invention.

FIG. 4 is a schematic sectional view schematically showing a conventional measuring device.

FIG. 5 is a table showing measurement results according to an example of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Coating adhesion amount measuring device 12 ... X-ray source 14 ... Space part 16 ... Measurement head 18 ... Movement device 20 ... Vacuum pump 22 ... Detector 24 ... Spectral crystal 26 ... Spectroscope 28A, 28B ... Piping 30A, 30B ... Electromagnetic Valve M: Metal plate

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Kimi Yamamoto 1-term Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture F-term (reference) 2R001 AA01 BA04 CA01 EA01 JA01 JA05 JA06 JA09 JA14 JA20 KA11 MA05 NA07 NA16

Claims (5)

[Claims] 1. A surface-treated film for measuring the amount of adhesion of the film based on fluorescent X-rays generated when the surface of the product is irradiated with X-rays while conveying the product having the film formed by the surface treatment. A method for measuring the amount of adhesion, comprising: a measurement head having a space surrounding a fluorescent X-ray generation site on the product surface together with an X-ray source for irradiating the X-ray;
A method for measuring the amount of adhesion of a surface-treated film, wherein the measuring head is brought into close contact with the surface of the product while moving at the same speed as the transport speed of the product, and the space is evacuated to measure X-ray fluorescence. . 2. The surface according to claim 1, wherein the measuring head is accelerated from an initial position to the same speed as the transport speed, and returns to the initial position after measuring the fluorescent X-rays. Method for measuring the amount of adhesion of the treated film. 3. An apparatus for measuring the amount of coating of a surface-treated film based on fluorescent X-rays generated when X-rays are irradiated on the surface of a product having a film formed by surface treatment. A measurement head having a space surrounding a fluorescent X-ray generation site on the product surface together with the X-ray source for irradiating the X-ray,
A surface treatment comprising: moving means for moving at the same speed as the transport speed of the product; and vacuum suction means for bringing the measuring head into close contact with the surface of the product during the movement and vacuuming the space. A device for measuring the amount of coating applied. 4. A control means for accelerating the measuring head from an initial position to the same speed as the transport speed, measuring the fluorescent X-rays, and returning to the initial position. An apparatus for measuring the amount of adhesion of a surface treatment film according to claim 3. 5. The measuring method according to claim 3, wherein a seal member for improving airtightness is provided at an opening end located on a product side of the measuring head. apparatus.