JP2004085471A - Device for evaluating barrier performance of carbon barrier film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for evaluating the barrier property of a carbon barrier film, which can simply and quickly evaluate the barrier property in a plastic container, whose surface is coated with the carbon barrier film or a sheet whose surface is coated with the carbon barrier film. <P>SOLUTION: There are provided a light source for irradiating with light a member to be evaluated, consisting of the plastic container, whose surface is coated with the carbon barrier film or the plastic sheet, whose surface is coated with the carbon barrier film, a light receiving means for receiving the light transmitted through the member to be evaluated, a spectroscopic means, disposed in an optical path between the light source and the light-receiving means and for separating the light in the optical path into a first light, having a wavelength band starting from green to ultraviolet, and a second light having a wavelength band starting from red to infrared, and an information processing means for processing a first light-receiving signal outputted at the light-receiving means on the basis of the first light and for processing a second light-receiving signal outputted at the light-receiving means on the basis of the second light. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a carbon barrier film barrier property evaluation apparatus for evaluating the barrier property of a carbon barrier film in a plastic container or a plastic sheet having a carbon barrier film coated on the surface.
[0002]
[Prior art]
A plastic container, for example, a PET bottle, has a carbon film on the surface of the plastic container to prevent permeation of oxygen from outside, permeation of carbon dioxide and moisture from inside (for example, carbonated drinking water), and elution of pet resin components. Attempts have been made to coat a carbon film such as DLC (Diamond Like Carbon) on the inner surface or the outer surface using a coating apparatus.
[0003]
When a barrier film is coated on such a plastic container surface with a carbon barrier film coating apparatus, it is important to evaluate the barrier properties of the carbon barrier film. In particular, in the case of application to a PET bottle or the like, it is required to evaluate a large number of bottles that are mass-produced as quickly as possible.
[0004]
By the way, conventionally, in the evaluation of the barrier properties of a plastic container having a surface coated with a carbon barrier film or a sheet having a surface coated with a carbon barrier film, the following gas permeability measurement methods are employed. .
[0005]
1) After storing carbonated water or water in a plastic container coated with a carbon barrier film, for example, a plastic bottle coated with a carbon barrier film, and sealing it, retaining carbon dioxide or moisture for measuring a change over time in gas pressure or weight in the plastic bottle. Rate measurement method.
[0006]
2) A sheet of a desired size is cut out from a PET bottle coated with a carbon barrier film as a test piece, and the test piece is inserted into a closed container so as to separate the container up and down, and carbon dioxide and oxygen are supplied to the separated lower chamber. A differential pressure method according to JIS K7126, in which the container is sealed, and the upper chamber is left, for example, in a vacuum state, and the amount of carbon dioxide and oxygen permeating the test piece from the lower chamber and flowing into the upper chamber is measured.
[0007]
3) A sheet of a desired size is cut out from a PET bottle coated with a carbon barrier film as a test piece, and the test piece is inserted into a closed container so that the container is separated into right and left, and carbon dioxide and oxygen are separated into the separated left chamber. Continuously supply, continuously supply a carrier gas such as nitrogen to the right chamber, and introduce the exhaust gas from the right chamber to the sensor, where the test piece is transmitted from the left chamber to the right chamber. MOCON method that measures the amount of carbon dioxide and oxygen that have flowed in.
[0008]
[Problems to be solved by the invention]
However, in the gas permeation rate measuring methods 1) to 3) described above, gases such as carbon dioxide and oxygen used have low permeability to the PET film coated with the carbon barrier film or the sheet cut out from this PET bottle. However, there is a problem that the measured value does not reach a steady value unless a sufficiently long leaving time (at least 3 days) is set.
[0009]
Specifically, in the MOCON method of the above 3), the distribution of the oxygen concentration and the carbon dioxide concentration in the pet resin and the carbon barrier film does not reach a steady state in the initial stage of the measurement, so that the measured oxygen permeation amount and the carbon dioxide amount are reduced. Causes aging. FIG. 10 shows an example (theoretical value) of a change in the amount of oxygen permeation and the amount of carbon dioxide measured by such a method. It can be seen that it takes about two to three days for the oxygen permeation amount to be stable, and about one to two weeks for carbon dioxide. This is the time it takes for the concentration distribution to reach a steady state, which is a long time due to the low gas permeation rate.
[0010]
The present inventors have determined that the barrier properties of a plastic container or a sheet coated with a carbon barrier film on the surface thereof depend on the film quality (specifically, film thickness and crystallinity) of the carbon barrier film. And that the film thickness and crystallinity specifically appear in the transmittance of light having a specific wavelength band and the like, and that the barrier property caused by the film thickness and crystallinity can be easily and quickly evaluated. Heading, which has led to the present invention.
[0011]
[Means for Solving the Problems]
The apparatus for evaluating the barrier property of a carbon barrier film according to the present invention is a light source for irradiating light to a plastic container having a surface coated with a carbon barrier film or a member to be evaluated made of a plastic sheet having a surface coated with a carbon barrier film. When,
Light receiving means for receiving light transmitted through the evaluated member,
A spectroscope disposed in an optical path between the light source and the light receiving unit, for separating the light in the optical path into first light having a green to ultraviolet wavelength band and second light having a red to infrared wavelength band; Means,
Information processing means for processing a first light receiving signal based on the first light output by the light receiving means, and processing a second light receiving signal based on the second light output by the light receiving means;
It is characterized by having.
[0012]
Another apparatus for evaluating the barrier property of a carbon barrier film according to the present invention includes a plastic container having a carbon barrier film coated on its surface or a member to be evaluated made of a plastic sheet having a carbon barrier film coated on its surface. A first light source for irradiating a first light having a band,
A second light source for irradiating the evaluated member with second light having a red to infrared wavelength band,
Light irradiation switching means for irradiating the evaluated member with either the first light or the second light;
Light receiving means for receiving light transmitted through the evaluated member,
Information processing means for processing a first light receiving signal based on the first light output by the light receiving means, and processing a second light receiving signal based on the second light output by the light receiving means;
It is characterized by having.
[0013]
The information processing unit reads, for example, a transmittance resulting from a thickness of a carbon barrier film of the evaluated member from a first light receiving signal based on the first light output by the light receiving unit, and converts the transmittance into a previously stored film thickness. The light-absorbance reference value (set value) is compared to determine the quality of the thickness of the carbon barrier film, and for example, the evaluation target member is obtained from a second light-receiving signal based on the second light output by the light-receiving means. The transmittance of the carbon barrier film due to the crystallinity is read and compared with an absorbance reference value (set value) caused by the previously stored crystallinity to determine the crystallinity of the carbon barrier film. You.
[0014]
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the present invention will be described in detail.
[0015]
First, the principle of the apparatus for evaluating the barrier properties of a carbon barrier film according to the present invention will be described.
[0016]
A test piece cut from a plastic container coated with a carbon barrier film is prepared. This test piece is composed of a plastic substrate and a carbon barrier film coated on the substrate. Three kinds of test pieces were prepared as Sample A, Sample B, and Sample C. As a fourth sample, a “blank” as a plastic substrate before coating the barrier film was prepared.
[0017]
The sample A is prototyped under conditions where the thickness and crystallinity of the carbon barrier film are appropriate. This sample A is a sample whose film thickness and crystallinity are both standard. Sample B is prototyped under the condition that the thickness of the carbon barrier film is appropriate, but the crystallinity is twice as poor as that of Sample A. Sample C is prototyped under the condition that the thickness of the carbon barrier film is about 1/3 of an appropriate value.
[0018]
A light source that emits white light on a light path, light receiving means such as a lens, a slit, a diffraction type spectroscope and a photodiode as optical means are arranged in this order, and the light receiving means is an information processing apparatus such as a personal computer. Using a test apparatus having a configuration connected to the above, the four samples are respectively arranged in the optical path between the diffraction type spectroscope and the light receiving means, and the spectral resolution of the diffraction type spectrometer is 2 nm from the ultraviolet range to the visible range, Further, transmission spectra of the above four types of samples in the near infrared region were measured. The result is shown in FIG. FIG. 1 also shows ultraviolet, blue, green, and red spectral bands as general classifications.
[0019]
The following results can be clearly understood from FIG.
[0020]
Samples A, B, and C coated with the carbon barrier film have a lower light transmittance than the blank, but the manner of reduction in the transmittance varies depending on the sample. Has the smallest decrease in transmittance. Although the transmittance of Samples A and B, in which the film thickness of the carbon barrier film is appropriate, is remarkable in all of the ultraviolet, blue, and green bands, the transmittance of Sample B in the long wavelength region (that is, the red band) is high. Only shows a decrease in transmittance.
[0021]
In general, it is preferable to convert the transmittance into an absorbance in order to quantitatively handle the decrease in the transmittance. The conversion method from the transmittance to the absorbance is obtained by taking the logarithm (base 10) of the value obtained by dividing the transmittance of each of the samples A, B, and C at each wavelength by the transmittance of the blank, and multiplying the result by −1 to obtain the absorbance ( abs). The result converted to the absorbance is shown in FIG.
[0022]
The absorbance on the vertical axis in FIG. 2 is a physical quantity proportional to the concentration or amount of the substance causing the absorption according to Lambert-Beer's law. Therefore, it can be interpreted that the absorbance at each wavelength reflects information on the film quality of the carbon barrier film. Here, the film quality includes both the film thickness and the crystallinity constituting the carbon barrier film. The crystallinity mainly refers to the ratio of the composition of DLC (Diamond Like Carbon) and graphite.
[0023]
From FIG. 2, the difference between the sample A and the sample C, which were manufactured so that only the film thickness was different in the film quality information of the carbon barrier film, was directly reflected in the magnitude of the absorbance. I find good. From the viewpoint of obtaining a more significant signal, it is preferable to select light in the ultraviolet, blue, or green band and compare absorbance (or transmittance). Quantitatively, it is desirable to select light having a wavelength range of 300 to 550 nm, and more preferably light having a wavelength range of 325 to 500 nm, at which a large difference in transmittance is obtained.
[0024]
On the other hand, the sample B, which was produced under the condition that the thickness of the carbon barrier film is appropriate, but the crystallinity of the carbon barrier film is twice as poor as that of the sample A, shows that all wavelength bands are different from the absorbance curve of the sample A. Thus, an absorbance curve is obtained by adding an approximately constant amount of absorbance. This result indicates that Sample B contains a greater amount of the black composition substance than Sample A. Actually, as a result of Raman spectroscopy analysis of the carbon barrier film of Sample B, it is found that the carbon barrier film of Sample B has a higher proportion of graphite composition (correspondingly, a lower proportion of DLC) than that of Sample A. .
[0025]
The method of evaluating crystallinity using Raman spectroscopy is described in Masanobu Yoshikawa and Keiko Iwagami, "Structural Evaluation of Diamond-like Carbon Film by Raman Spectroscopy", Surface Technology, Vol. 49, no. 7, p750-756, (1998).
[0026]
Further, when the proportion of the graphite composition increases as an index of crystallinity, the barrier properties decrease. It is generally known that the graphite is black and has a uniform absorption in the ultraviolet and visible spectrums.
[0027]
For the above reasons, it is understood from the absorbance curves of the samples A and B in FIG. 2 that the carbon barrier film of the sample B contains more graphite than the sample A, which lowers the barrier property.
[0028]
Therefore, the difference between the sample A and the sample B, which were prototyped so that only the crystallinity was different in the film quality information of the carbon barrier film, was in a long wavelength region where a remarkable difference was observed in the magnitude of the absorbance, that is, in the red and near infrared regions. It can be seen that the absorbances at the wavelengths in the band need to be compared. From the viewpoint of obtaining a more significant signal, it is preferable to select light in the red and near-infrared bands and compare the absorbance (or transmittance). Quantitatively, it is desirable to select light having a band in the range of 600 nm to 750 nm, which gives a large difference in transmittance and is less affected by the difference in film thickness.
[0029]
(1st Embodiment)
FIG. 3 is a schematic view showing an apparatus for evaluating a barrier property of a carbon barrier film according to the first embodiment of the present invention.
[0030]
For example, white light is emitted from the light source 1 in the figure. An optical unit 4 including a lens 2 and a slit 3 is disposed in the optical path of white light in front of the light source 1. For example, a light receiving unit 5 such as a photodiode is disposed behind the optical unit 4 and has a function of receiving measurement light, which will be described later, and converting the light intensity into an electric signal. As the light receiving means 5, a photomultiplier tube or the like can be used in addition to the photodiode.
[0031]
For example, a first spectroscopic unit 6 such as an interference filter is disposed in an optical path between the optical unit 4 and the light receiving unit 5 (between the optical unit 4 and a test piece described later). It has a function of dispersing the first light having a wavelength band from green to ultraviolet, preferably a band having a wavelength in the range of 300 to 550 nm. Further, for example, a second spectral unit 7 such as an interference filter is disposed in the optical path so as to be switchable with respect to the first spectral unit 6 by an output signal from an information processing device described later, for example. And has a function of dispersing the second light having a wavelength band from about to infrared, preferably a wavelength in a range of 600 nm to 750 nm. As the first and second spectral units 6, 7, a color filter, a dispersion type spectroscope, a diffraction type spectroscope, or the like can be used in addition to the interference filter. A color filter is a filter utilizing the absorption characteristics of the material itself, and examples of the material include glass, plastic, crystals, and liquid. The first and second splitters 6, 7 which can be switched to each other are arranged on the incident side of a test piece described later, but may be arranged on the emission side of this test piece.
[0032]
The light receiving means 5 is connected through a cable 8 to an information processing device 10 such as a personal computer having a display 9 such as a CRT, and a light receiving signal of the light receiving means 5 is transmitted. The information processing apparatus 10 uses an absorbance reference value (set value) previously calculated from the transmittance due to the film thickness as described in the above-described principle and the transmittance due to crystallinity in advance as described in the above-described principle. The calculated absorbance reference value (set value) is stored, and the result of comparison with the received light signal is displayed on the display 9.
[0033]
Next, the barrier evaluation of the carbon barrier film by the carbon barrier film evaluation apparatus shown in FIG. 1 will be described.
[0034]
(First evaluation operation)
A test piece 11 cut out from a plastic container coated with a carbon barrier film is disposed in an optical path between the first spectral unit 6 and the light receiving unit 5 while being supported by a holder (not shown). The test piece 11 includes a plastic substrate 12 and a carbon barrier film 13 coated on the substrate 12. In this state, for example, white light is emitted from the light source 1. The emitted white light 14 is condensed and restricted in width while passing through the lens 2 and the slit 3, and the white light 14 is converted to green by the first spectral unit 6 for evaluating the thickness information of the carbon barrier film. The light is split into light having an ultraviolet wavelength band (first light), and is applied to the test piece 11 as measurement light 15. The measuring light 15 passes through the test piece 11 and is incident on the light receiving means 5. The light receiving unit 5 outputs a light receiving signal corresponding to the light intensity of the incident measurement light having a wavelength band from green to ultraviolet through the cable 8 to the information processing device 10. In the information processing apparatus 10, since the absorbance reference value calculated from the transmittance caused by the film thickness is stored in advance, the absorbance reference value is compared with the measured absorbance based on the light reception signal, and the comparison is performed. The judgment result is displayed on the display 9.
[0035]
(Second evaluation operation)
The first spectral unit 6 is switched to the second spectral unit 7 in response to an output signal from the information processing device 10, and the light source 1 emits, for example, white light. At this time, the white light is separated into light (second light) having a wavelength band from red to infrared for the evaluation of the crystallinity information of the carbon barrier film by the second spectroscopic means 7 and is applied to the test piece 11 as measurement light. The light is emitted, transmitted and incident on the light receiving means 5. The light receiving unit 5 outputs a light receiving signal corresponding to the light intensity of the incident measurement light having a wavelength band from red to infrared through the cable 8 to the information processing device 10. In this information processing device 10, since the absorbance reference value calculated from the transmittance due to the crystallinity is stored in advance, the absorbance reference value is compared with the measured absorbance based on the received light signal, and the determination based on the comparison is performed. The result is displayed on the display 9.
[0036]
FIG. 4 shows an evaluation chart of such a test piece.
[0037]
In the first evaluation operation, the magnitude relationship between the absorbance (measured absorbance) of the first light having the wavelength band from green to ultraviolet processed by the information processing device 10 and the absorbance reference value is determined. At this time, if the measured absorbance is lower than the absorbance reference value, it is determined that the carbon barrier film of the test piece has an insufficient thickness, that is, is defective. On the other hand, if the measured absorbance is higher than the absorbance reference value, it is determined that the carbon barrier film of the test piece has an appropriate thickness.
[0038]
The test piece for which the thickness of the carbon barrier film was determined to be appropriate was subjected to the second evaluation operation and processed by the information processing apparatus 10 to absorb light of the second light having a wavelength band from red to infrared (measured absorbance). And the magnitude relationship between the absorbance and the absorbance reference value are determined. At this time, when the measured absorbance is higher than the absorbance reference value, it is determined that the carbon barrier film of the test piece has insufficient crystallinity, that is, is defective. On the other hand, when the measured absorbance is lower than the absorbance reference value, the carbon barrier film of the test piece is determined to have proper crystallinity, and is finally determined to be a good product.
[0039]
As described above, according to the barrier property evaluation apparatus of the first embodiment, for example, the film quality of the carbon barrier film, that is, the film thickness of the test piece cut from the carbon barrier film-coated plastic container based on the chart shown in FIG. Whether or not the crystallinity is appropriate can be determined, and the barrier property can be evaluated.
[0040]
Therefore, according to the present invention, the quality (thickness and crystallinity) of the carbon barrier film coated on the PET bottle due to the barrier property, that is, the barrier property can be evaluated in a short time. In this way, the quick evaluation of the barrier properties of bottles can speed up the sampling inspection of product bottles to be shipped, perform 100% inspection, or incorporate this device into barrier film deposition equipment and barrier film coating mass production equipment, etc. As a result, the soundness evaluation of the production process can be speeded up.
[0041]
In the above-described first embodiment, as shown in FIG. 3, a test piece 11 cut out from a plastic container coated with a carbon barrier film as a member to be evaluated is used for the first spectroscopic unit 6 (or the second spectroscopic unit 7) and the light receiving unit 5. As shown in FIG. 5, a carbon container coated with a carbon barrier film (for example, a PET bottle coated with a carbon barrier film) 16 as a member to be evaluated is received by the first spectral unit 6 (or the second spectral unit 7) as shown in FIG. Even if it is disposed in the optical path between the means 5, the film quality (thickness and crystallinity) resulting from the barrier property of the carbon barrier film covering the PET bottle 16 non-destructively by the same operation as in the first embodiment. That is, the barrier property can be evaluated in a short time.
[0042]
(Example 1)
Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG.
[0043]
A test piece 11 cut out from a plastic container coated with a carbon barrier film or a test piece 11 that is a part of a sheet coated with a carbon barrier film is disposed in a light path between the first spectral unit 6 and the light receiving unit 5 by being supported by a holder (not shown). . The test piece 11 includes a plastic substrate 12 and a carbon barrier film 13 coated on the substrate 12. In this state, white light was emitted from the light source 1 composed of a tungsten bulb. The emitted white light 14 is condensed and restricted in width while passing through the lens 2 and the slit 3, and becomes a parallel light beam having a cross-sectional shape of 4 mm × 4 mm. The light was separated into light (first light) having a wavelength of 400 nm by a filter, irradiated to the test piece 11 as measurement light 15, transmitted, and incident on a photomultiplier tube as the light receiving means 5. The transmission bandwidth of the interference filter is 20 nm, and the above-mentioned wavelength value means the center wavelength of the transmission band. A light receiving signal corresponding to the light intensity of the measuring light having a wavelength of 400 nm is output from the light receiving means 5 to the information processing device 10 through the cable 8, and the light receiving signal is converted from the transmittance caused by the film thickness stored in advance. The display 9 was compared with the calculated absorbance reference value, and the result of the comparison (the appropriateness of the film thickness) was displayed on the display 9. When it was determined that the film thickness was proper by this operation, the light was switched from the first spectral unit 6 to the second spectral unit 7 according to the output signal from the information processing apparatus 10, and the light source 1 similarly emitted white light. At this time, the white light is separated into light (second light) having a wavelength of 700 nm by the interference filter serving as the second spectral unit 7, irradiates the test piece 11 as measurement light, transmits, and enters the light receiving unit 5. . The transmission bandwidth of the interference filter is 20 nm, and the above-mentioned wavelength value means the center wavelength of the transmission band. A light receiving signal corresponding to the light intensity of the measurement light having a wavelength of 700 nm is output from the light receiving means 5 to the information processing apparatus 10 through the cable 8, and the light receiving signal is calculated from a transmittance previously stored due to crystallinity. The results were compared with the absorbance reference values, and the results of the comparison (good or bad crystallinity) were displayed on the display 9 to evaluate the barrier properties of the carbon barrier film.
[0044]
The above evaluation operation could be completed within several minutes, and the oxygen barrier property, which normally takes 2 to 3 days, could be evaluated in a short time.
[0045]
An interference filter or a color filter for separating the wavelength into light having a wavelength of 400 nm (first light) as a first dispersing means, and a second separating means for separating wavelength into light having a wavelength of 700 nm (second light). If an interference filter or a color filter is prepared and inserted alternately on the optical path of the measurement light 9, the above process can be completed within a few seconds.
[0046]
The evaluation device of the present invention is mounted on a carbon barrier film coating device, and can be used to quickly check whether the coating operation of the device is normal during the initial start-up operation or after maintenance. For example, the coating is performed a plurality of times appropriately for each chamber of the coating apparatus, and the barrier property of each bottle is quantified by the above-described apparatus, and it can be confirmed whether or not a necessary barrier property is obtained.
[0047]
If such a measurement is performed by the conventional method, it takes 2 to 3 days per chamber with oxygen, and in the case of a coating apparatus having 30 chambers, it takes a period of one month in total, resulting in a large cost. It is difficult to apply in practical use. On the other hand, in the apparatus of the present invention, the measurement can be completed in a few hours and the production can be started in a few minutes to several tens of minutes per sample, and even in 30 chambers, if the preparation such as the adhesion and mounting of the bottle is performed in parallel. At the same time, if the coating device has a problem and the barrier property cannot be obtained as expected, it can be found and corrected immediately.
[0048]
Furthermore, if the apparatus of the present invention is mounted on a barrier film coating apparatus, it is usually used for a 100% inspection or a sampling inspection for screening for the presence or absence of coating, thereby detecting defective products, optimizing or controlling the conditions of the coating process, and controlling maintenance time. It can be used for detection, etc., and can be used to maintain the quality of coating bottles. In addition to the barrier film coating device, the present invention is applied to a device that performs some processing after coating the barrier film, such as a device for cleaning a plastic container, a device for filling a plastic container with a beverage, and a device for capping a plastic container. The same processing can be performed by incorporating the device. It is also possible to incorporate these devices into a beverage plant that is a combination.
[0049]
(2nd Embodiment)
FIG. 6 is a schematic diagram showing an apparatus for evaluating the barrier properties of a carbon barrier film according to the second embodiment of the present invention. In FIG. 6, the same members as those in FIG. 3 described above are denoted by the same reference numerals, and description thereof will be omitted.
[0050]
The barrier evaluation apparatus has a structure in which a convex lens 17, an optical fiber 18, and a convex lens 19 are arranged on the optical path in front of the first spectral unit 6 (or the second spectral unit 7). The optical fiber 18 is inserted from the mouth of a plastic container coated with a carbon barrier film (for example, a plastic bottle coated with a carbon barrier film) 16 into the inside thereof such that the tip faces the inner surface of the plastic bottle 16 at a desired distance, Further, the convex lens 19 is disposed between the tip of the optical fiber 18 and the inner surface of the plastic bottle 16. The optical fiber may be a single mode fiber, a multimode fiber, or a bundle fiber. The core diameter of the optical fiber is not limited, and may be a thick one such as a glass rod.
[0051]
According to the apparatus for evaluating the barrier property of the carbon barrier film having the configuration shown in FIG. 6, for example, the white light 14 emitted from the light source 1 is condensed and regulated while passing through the lens 2 and the slit 3. The white light 14 is split into light (first light) having a wavelength band from green to ultraviolet by the first splitting means 6 to evaluate the thickness information of the carbon barrier film, and is condensed by the convex lens 17 to be formed on the optical fiber 18. After the light is emitted, the measuring light 15 emitted from the optical fiber 18 is converted into a parallel light flux through the convex lens 19 and is irradiated on the inner surface of the PET bottle 16 coated with the carbon barrier film. The measurement light 15 passes through the side wall of the PET bottle 16 and enters the light receiving unit 5. The light receiving unit 5 outputs a light receiving signal corresponding to the light intensity of the incident measurement light having a wavelength band from green to ultraviolet through the cable 8 to the information processing device 10. In the information processing apparatus 10, since the absorbance reference value calculated from the transmittance caused by the film thickness is stored in advance, the absorbance reference value is compared with the measured absorbance based on the light receiving signal, and the determination based on the comparison is performed. The result is displayed on the display 9.
[0052]
The first spectral unit 6 is switched to the second spectral unit 7 in response to an output signal from the information processing device 10, and the light source 1 emits, for example, white light. At this time, the white light is separated into light (second light) having a wavelength band from red to infrared for evaluating the crystallinity information of the carbon barrier film by the second spectral means 7, and the carbon barrier film-coated pet is used as measurement light. Irradiation is performed on the inner surface of the bottle 16. The measurement light 15 passes through the side wall of the PET bottle 16 and enters the light receiving unit 5. The light receiving unit 5 outputs a light receiving signal corresponding to the light intensity of the incident measurement light having a wavelength band from red to infrared through the cable 8 to the information processing device 10. In this information processing device 10, since the absorbance reference value calculated from the transmittance due to the crystallinity is stored in advance, the absorbance reference value is compared with the measured absorbance based on the received light signal, and the determination based on the comparison is performed. The result is displayed on the display 9.
[0053]
When a predetermined operation is performed and the measurement is completed, the optical fiber or the like is extracted from the mouth of the plastic bottle 16 by a driving mechanism (not shown).
[0054]
Therefore, in the second embodiment, the film quality (thickness and crystallinity) of the carbon barrier film coated non-destructively on the PET bottle by the same operation as the first embodiment, that is, the barrier property is evaluated in a short time. Can be.
[0055]
In the non-destructive evaluation of the PET bottle 16 shown in FIG. 5 of the above-described first embodiment, the spectroscopic measurement light is transmitted through the two side walls of the PET bottle 16, whereas the second embodiment is different. Since the measurement light is transmitted through one side wall of the PET bottle 16 via the optical fiber 18, the PET bottle 16 shown in FIG. 5 of the first embodiment described above can be compared with the non-destructive evaluation of the barrier property. Highly accurate nondestructive evaluation of barrier properties can be performed.
[0056]
(Third embodiment)
FIG. 7 is a schematic diagram showing an apparatus for evaluating the barrier properties of a carbon barrier film according to a third embodiment of the present invention. In FIG. 7, the same members as those in FIG. 3 described above are denoted by the same reference numerals, and description thereof will be omitted.
[0057]
This barrier property evaluation apparatus has a light source 1 composed of a plurality of, for example, three tungsten spheres, and a diffusion plate 20 is arranged in front of these light sources 1. It is preferable that the diffuser plate 20 is disposed at a long distance from the light source 1 because the white light emitted from the light sources can be uniform illumination light.
[0058]
The first spectral unit 6 is disposed on an optical path in front of the diffusion plate 20 and transmits light on the optical path (in the third embodiment, light transmitted through a plastic container coated with a carbon barrier film, for example, a PET bottle 16 coated with a carbon barrier film). It has a function of dispersing the first light having a wavelength band from green to ultraviolet, preferably a wavelength band in a range of 300 to 550 nm. The second spectral unit (not shown) is arranged in the optical path so as to be switchable with respect to the first spectral unit 6 by an output signal from the information processing apparatus 10, for example. It has a function of dispersing the transmitted light of the PET bottle 16) into a second light having a wavelength range from red to infrared, preferably a wavelength range of 600 nm to 750 nm. The uniformed illumination light is applied to the test object as the measurement light 9, and the transmitted measurement light 9 is wavelength-resolved by the spectral unit 8. As the first and second spectral means, a color filter and an interference filter can be used, and a color filter is more preferable in terms of cost. Specifically, a color filter B390 manufactured by HOYA is suitable as the first spectral unit, and a color filter B60 manufactured by HOYA is suitable as the second spectral unit. However, these spectral means are not limited to the color filters of the specifications described herein.
[0059]
The measurement light wavelength-separated by the first spectral unit 6 (or the second spectral unit) is received by the CCD camera 21 as the light receiving unit, and is transmitted to the information processing apparatus 10 through the cable 8 as a light receiving signal of two-dimensional image information. Is output. The CCD camera 21 may be monochrome. The CCD camera 21 is provided with a lens, and it is preferable that the focal position of the imaging system be adjusted to the device under test or to the diffusion plate 20.
[0060]
According to the third embodiment, the PET bottle 16 coated with the carbon barrier film is disposed on the optical path between the diffusion plate 20 and the first dispersing unit 6 (or the second dispersing unit). By the same action as in the embodiment, the quality (thickness and crystallinity) of the carbon barrier film coated non-destructively on the PET bottle, that is, the barrier property can be evaluated in a short time.
[0061]
In the third embodiment, uniform illumination light is used as measurement light, and two-dimensional image information is added by the first spectral unit 6 (or the second spectral unit) including a color filter and the image capturing system of the CCD camera 21. In addition, the evaluation of the barrier property of the carbon barrier film in each part of the PET bottle 16 can be performed in a short time without destruction.
[0062]
(Fourth embodiment)
FIG. 8 is a schematic view showing an apparatus for evaluating the barrier property of a carbon barrier film according to a fourth embodiment of the present invention. In FIG. 8, the same members as those in FIG. 3 described above are denoted by the same reference numerals, and description thereof will be omitted.
[0063]
This barrier property evaluation apparatus has a configuration in which a color CCD camera with three color filters of RGB (red, green, and blue) is provided as the light receiving unit 22 and the first and second spectral units are omitted.
[0064]
According to the apparatus for evaluating the barrier property of the carbon barrier film having the configuration shown in FIG. 8, the test piece 11 cut out from the plastic container coated with the carbon barrier film is supported by the holder (not shown) on the optical path between the light source 1 and the light receiving means 22. And place it. When, for example, white light is emitted from the light source 1 in this state, the white light 14 is condensed and restricted in width while passing through the lens 2 and the slit 3. 11 is irradiated. The measurement light 15 passes through the test piece 11 and is incident on the color CCD camera through three color filters of RGB (red, green, and blue) in the light receiving means 22. The light receiving means 22 collectively outputs the received light signals corresponding to the light intensity of the measuring light having the wavelength band of green to ultraviolet and the wavelength band of red or near-infrared which are incident to the information processing device 10 through the cable 8. You. In the information processing device 10, since the absorbance reference value calculated in advance from the film thickness and the transmittance caused by the crystallinity is stored, the absorbance reference value related to the film thickness and the wavelength band from green to ultraviolet are stored. Compare the measured absorbance based on the received light signal of the measurement light with, and simultaneously compare the measured absorbance based on the received light signal of the measurement light having the red to infrared wavelength band and the absorbance reference value related to the crystallinity. , Are displayed on the display 9.
[0065]
Therefore, in the fourth embodiment, the film quality (thickness and crystallinity) of the carbon barrier film of the test piece, that is, the barrier property can be evaluated in a short time as in the first embodiment described above.
[0066]
Further, in the fourth embodiment, the first and second spectroscopy units can be omitted, so that it is possible to realize an apparatus for evaluating the barrier property of a carbon barrier film having a simplified structure as compared with the first embodiment.
[0067]
(Fifth embodiment)
FIG. 9 is a schematic view showing an apparatus for evaluating a barrier property of a carbon barrier film according to a fifth embodiment of the present invention. In FIG. 9, the same members as those in FIG. 3 described above are denoted by the same reference numerals, and description thereof will be omitted.
[0068]
This barrier property evaluation device includes a first light emitting diode 23 that emits light having a wavelength band from green to ultraviolet (first light) and a second light emitting diode 24 that emits light having a wavelength band from red to infrared (second light). As a light source, and the first and second light emitting diodes 23 and 24 are arranged such that their emitted light crosses each other at an angle of 90 °. The reflecting mirror 25 is disposed at the intersection of the radiated light of the first and second light emitting diodes 23 and 24 so as to be able to move back and forth so as to refract the radiated light of the first light emitting diode 23 by 90 °. In this barrier evaluation apparatus, the first and second spectral units are omitted.
[0069]
According to the barrier property evaluation apparatus shown in FIG. 9, the test piece 11 cut out from the plastic container coated with the carbon barrier film is supported and arranged on the optical path between the optical means 4 and the light receiving means 5 by a holder (not shown). . In this state, the first light emitting diode 23 is operated to emit light (first light) having a wavelength band from green to ultraviolet. The emitted first light is reflected by the reflecting mirror 25 at 90 °, and is condensed and restricted in its width while passing through the lens 2 and the slit 3. The first light is irradiated and transmitted as the measuring light 15 onto the test piece 11. The light is incident on the light receiving means 5. The light receiving unit 5 outputs a light receiving signal corresponding to the light intensity of the incident measurement light having a wavelength band from green to ultraviolet through the cable 8 to the information processing device 10. In the information processing apparatus 10, since the absorbance reference value calculated from the transmittance caused by the film thickness is stored in advance, the absorbance reference value is compared with the measured absorbance based on the light reception signal, and the comparison is performed. The judgment result is displayed on the display 9.
[0070]
The operation of the first light emitting diode 23 is stopped by an output signal from the information processing device 10, and the reflecting mirror 25 is moved to a position deviated from the optical path of the first light emitting diode 23. To emit light having a red to infrared wavelength band (second light). The emitted second light is condensed and restricted in its width while passing through the lens 2 and the slit 3, is irradiated as the measuring light 15 on the test piece 11, is transmitted, and is incident on the light receiving means 5. The light receiving unit 5 outputs a light receiving signal corresponding to the light intensity of the incident measurement light having a wavelength band from red to infrared through the cable 8 to the information processing device 10. In this information processing device 10, since the absorbance reference value calculated from the transmittance due to the crystallinity is stored in advance, the absorbance reference value is compared with the measured absorbance based on the received light signal, and the determination based on the comparison is performed. The result is displayed on the display 9.
[0071]
Therefore, in the fifth embodiment, the film quality (thickness and crystallinity) of the carbon barrier film of the test piece, that is, the barrier property can be evaluated in a short time as in the first embodiment.
[0072]
In the above-described fifth embodiment, if a mirror element that rotates at high speed and switches between transmission and reflection is used instead of the reflecting mirror, the barrier property of the carbon barrier film of the test piece is evaluated in milliseconds (msec). be able to.
[0073]
Further, in the fifth embodiment described above, instead of the movable reflecting mirror 25, a fixed half mirror is provided at the intersection of the radiated light of the first and second light emitting diodes 23 and 24. The first light and the second light are alternately transmitted through the test piece by arranging the light so as to be refracted by 90 ° and alternately performing the light emission of the first and second light emitting diodes 23 and 24. The barrier property of the carbon barrier film of the test piece can be evaluated at high speed.
[0074]
【The invention's effect】
As described above in detail, according to the barrier property evaluation apparatus for a carbon barrier film according to the present invention, the barrier property in a plastic container or a sheet in which a carbon barrier film is coated on the surface is simply and easily provided. It has a remarkable effect that it can be quickly evaluated, and as a result, can quickly determine the normality of the coating operation of the carbon barrier film coating apparatus for plastic containers or sheets, and can be used as an index for controlling the coating conditions.
[Brief description of the drawings]
FIG. 1 is a transmission spectrum diagram of four types of samples in an ultraviolet region, a visible region, and a near infrared region.
FIG. 2 is a characteristic diagram obtained by converting transmission spectra of samples A to C in FIG. 1 into absorbance.
FIG. 3 is a schematic view showing an apparatus for evaluating a barrier property of a carbon barrier film according to the first embodiment of the present invention.
FIG. 4 is an evaluation chart by the barrier evaluation apparatus according to the first embodiment of the present invention.
FIG. 5 is a schematic view showing a barrier property evaluation device in which a member to be evaluated is arranged in place of a carbon barrier film-coated PET bottle in the first embodiment of the present invention.
FIG. 6 is a schematic view showing an apparatus for evaluating a barrier property of a carbon barrier film according to a second embodiment of the present invention.
FIG. 7 is a schematic view showing an apparatus for evaluating a barrier property of a carbon barrier film according to a third embodiment of the present invention.
FIG. 8 is a schematic view showing an apparatus for evaluating a barrier property of a carbon barrier film according to a fourth embodiment of the present invention.
FIG. 9 is a schematic view showing an apparatus for evaluating a barrier property of a carbon barrier film according to a fifth embodiment of the present invention.
FIG. 10 is a characteristic diagram showing changes in oxygen permeation rate and carbon dioxide rate over time in a conventional PET bottle coated with a carbon barrier film.
[Explanation of symbols]
1. Light source,
4 optical means,
5, 21, 22 ... light receiving means,
6 first spectral means,
7 ... second spectroscopic means,
9 ... Display,
10 ... Information processing device,
11 Test piece,
14 ... white light,
15 ... Measurement light,
16: PET bottle coated with a carbon barrier film,
18 optical fiber,
20: Diffusing plate,
23 ... first light emitting diode,
24 ... second light emitting diode,
25 ... Reflection mirror.

Claims (8)

A light source for irradiating a light to a member to be evaluated made of a plastic container having a carbon barrier film coated on the surface or a plastic sheet having a carbon barrier film coated on the surface,
Light receiving means for receiving light transmitted through the evaluated member,
A spectroscope disposed in an optical path between the light source and the light receiving unit, for separating the light in the optical path into first light having a green to ultraviolet wavelength band and second light having a red to infrared wavelength band; Means,
And an information processing means for processing a first light receiving signal based on the first light output by the light receiving means and processing a second light receiving signal based on the second light output by the light receiving means. An apparatus for evaluating the barrier properties of a carbon barrier film, comprising: The said spectroscopy means is a 1st filter which selectively transmits in the wavelength band of green to ultraviolet light which is switchably arrange | positioned in the said optical path, and a 2nd filter which selectively transmits in the wavelength band of red to infrared light. 2. The apparatus for evaluating a barrier property of a carbon barrier film according to claim 1. The apparatus according to claim 1, wherein the light receiving unit is a color CCD that also serves as the spectral unit. The apparatus for evaluating the barrier property of a carbon barrier film according to claim 1, wherein an optical means having a lens for condensing light is further disposed in an optical path between the light source and the member to be evaluated. A first light source for irradiating a plastic container having a surface coated with a carbon barrier film or a member to be evaluated made of a plastic sheet having a surface coated with a carbon barrier film with first light having a wavelength band from green to ultraviolet;
A second light source for irradiating the evaluated member with second light having a red to infrared wavelength band,
Light irradiation switching means for irradiating the evaluated member with either the first light or the second light;
Light receiving means for receiving light transmitted through the evaluated member,
And an information processing means for processing a first light receiving signal based on the first light output by the light receiving means and processing a second light receiving signal based on the second light output by the light receiving means. An apparatus for evaluating the barrier properties of a carbon barrier film, comprising: The first light source is a light emitting diode emitting a first light having a wavelength band from green to ultraviolet, and the second light source is a light emitting diode emitting a second light having a red or infrared wavelength band. The apparatus for evaluating the barrier properties of a carbon barrier film according to claim 5, characterized in that: 6. The apparatus according to claim 5, wherein an optical unit having a lens for condensing light is further disposed in an optical path between the light irradiation switching unit and the member to be evaluated. . The carbon barrier film according to claim 1, wherein the green to ultraviolet wavelength band has a wavelength range of 300 nm to 550 nm, and the red to infrared wavelength band has a wavelength range of 600 nm to 750 nm. Barrier evaluation device.

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