JP2015227893A - Measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measuring method capable of evaluating surface wettability of an object, at high speed in a nondestructive manner.SOLUTION: A measuring method related to a certain situation includes: a step for irradiating an object OBJ with ultraviolet rays; a step for detecting fluorescence produced in the object OBJ; and a step for outputting a value showing the surface wettability of the object from intensity of the detected fluorescence. A separate measurement method related to another situation includes: a step for irradiating the object with the ultraviolet rays; a step for detecting the fluorescence produced in the object; and a step for outputting intensity of the fluorescence detected as a value showing the surface wettability of the object.

Description

  The present invention relates to a measurement method for evaluating the wettability of an object.

  For example, in a process in which an adhesive, a coating agent, a coating agent, or the like is applied to a polymer film or resin, a pretreatment is performed so as to enhance “wetting” on the surface (interface). In general, such treatment is referred to as “surface modification treatment” or the like. This surface modification treatment is realized by, for example, plasma treatment or corona treatment in a specific atmosphere.

  By the way, from the aspect of quality control, how much wettability is improved by such surface modification treatment is evaluated, and related process parameters (setting values) are appropriately reviewed based on the evaluation result. It is important to

  Conventionally, a measurement method called a droplet method has been adopted as a method for evaluating such wettability. In this droplet method, a predetermined amount of liquid (typically pure water) is dropped on the surface of an object, and an angle (“contact angle” or “ It is also a method of measuring (wet angle). The measured contact angle has a correlation with the magnitude of the surface tension generated in the dropped liquid, and the magnitude of the contact angle indicates the wettability of the object.

  For example, Patent Document 1 (Utility Model Registration No. 3150529) discloses a contact angle measuring device for measuring a contact angle using the principle of such a droplet method.

Utility Model Registration No. 3150529

  In the contact angle measuring device using the droplet method as disclosed in Patent Document 1 described above, the wettability cannot be evaluated in-line. That is, in the droplet method, since it is necessary to drop a liquid on an object, a destructive inspection is performed in principle. For this reason, the inspection of the objects flowing on the line is unavoidable, and it is impossible to inspect all the objects.

  Further, in the droplet method, the measurement result is greatly affected by the measurement environment (particularly vibration), and therefore it is necessary to prepare an environment satisfying predetermined conditions in order to install the measurement apparatus. Furthermore, the droplet method has a problem that it is difficult to reduce the size in principle, and a problem that the measurement accuracy cannot be increased in a range where the contact angle is relatively small (that is, a state with high wettability).

  Therefore, the present invention has been made to solve these problems, and an object of the present invention is to provide a measurement method capable of evaluating the wettability of the surface of an object at high speed and nondestructively.

A measuring method according to an aspect of the present invention includes a step of irradiating an object with ultraviolet light, a step of detecting fluorescence generated in the object, and a value indicating wettability on the surface of the object from the intensity of the detected fluorescence. Outputting.

  Preferably, the outputting step includes a step of calculating a contact angle corresponding to the detected fluorescence intensity and a step of outputting the calculated contact angle in accordance with the correspondence acquired in advance.

More preferably, the correspondence acquired in advance is acquired for each type of object.
Preferably, the measurement method further includes a step of performing a surface modification treatment on the object, and the outputting step includes the result of detecting the fluorescence generated in the object before the surface modification treatment, and the surface modification. A step of calculating a value indicating wettability on the surface of the object based on a difference from a result of detecting the fluorescence generated in the object after performing the quality treatment.

  More preferably, the surface modification treatment includes a treatment for generating at least one of a carboxyl group and a carbonyl group on the surface of the object.

  A measurement method according to another aspect of the present invention includes a step of irradiating an object with ultraviolet light, a step of detecting fluorescence generated in the object, and an intensity of fluorescence detected as a value indicating wettability on the surface of the object. Output.

  According to an aspect of the present invention, the wettability of the surface of an object can be evaluated at high speed and nondestructively.

It is a schematic diagram for demonstrating the measurement principle which concerns on embodiment of this invention. It is a schematic diagram of the apparatus used for a plasma processing. It is a figure which shows the graph which plotted the experimental result about a plasma processing. It is a figure for demonstrating the contact angle in a droplet method. It is a schematic diagram of the coating process containing a corona treatment apparatus. It is a typical external view of the measuring apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows the optical structure of the measuring apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows the electrical structure of the measuring apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows the electrical structure of the measuring apparatus which concerns on the 1st modification of embodiment of this invention. It is a schematic diagram which shows the electrical structure of the measuring apparatus which concerns on the 2nd modification of embodiment of this invention. It is a schematic diagram which shows the optical structure of the measuring apparatus which concerns on the 3rd modification of embodiment of this invention. It is a schematic diagram which shows the optical structure of the measuring apparatus which concerns on the 4th modification of embodiment of this invention. It is a figure which shows an example of the emission spectrum of the ultraviolet lamp (metal halide lamp) shown in FIG. It is a figure which shows an example of the characteristic of the wavelength filter shown in FIG. It is a schematic diagram which shows the control structure of the measuring device which concerns on embodiment of this invention. It is a figure which shows the graph which plotted the experimental result shown in FIG. 3 about the relationship between a contact angle and fluorescence intensity. It is a schematic diagram which shows the modification of the control structure of the measuring device which concerns on embodiment of this invention. It is a flowchart which shows the procedure of the wettability evaluation process (the 1) which concerns on embodiment of this invention. It is a flowchart which shows the procedure of the wettability evaluation process (the 2) which concerns on embodiment of this invention. It is a schematic diagram which shows an example of the surface modification process which concerns on embodiment of this invention. It is a flowchart which shows the procedure of the adjustment process of the surface modification process which concerns on embodiment of this invention.

  Embodiments of the present invention will be described in detail with reference to the drawings. Note that the same or corresponding parts in the drawings are denoted by the same reference numerals and description thereof will not be repeated.

[A. Measurement principle]
First, the measurement principle according to the embodiment of the present application will be described.

  The inventors of the present application have found that when a surface modification treatment is performed on an object, a fluorescent substance is generated with a high correlation with the degree of modification (degree of wettability). That is, the inventors of the present application have found that fluorescence having an intensity corresponding to the degree of surface modification can be generated by subjecting an object to surface modification treatment. The measurement method according to the embodiment of the present invention utilizes such a newly found physical / chemical phenomenon.

  FIG. 1 is a schematic diagram for explaining the measurement principle according to the embodiment of the present invention. With reference to FIG. 1, the measurement method according to the embodiment of the present application will be described in more detail.

  FIG. 1 illustrates a case where the surface modification process is performed on the object OBJ. As such surface modification treatment, typically, plasma treatment or corona treatment is known, and FIG. 1 illustrates the case of plasma irradiation. Moreover, as the object OBJ, a resin substrate, a film, or the like is typically assumed. FIG. 1 shows an object OBJ whose main material is polyimide as an example.

  Such a film contains C (carbon) atoms and H (hydrogen) atoms, and the surface modification treatment causes O (oxygen) in the atmosphere to bond with these atoms. Primarily, functional groups such as a carboxyl group (—COOH), a carbonyl group (> C═O), and a hydroxy group are generated. In addition, peroxides and epoxy groups can be generated. The presence of more such functional groups improves the wettability of the object OBJ. That is, the surface modification treatment includes treatment for generating at least one of a carboxyl group and a carbonyl group.

  The inventors of the present application thought that the fluorescence generated from the object OBJ by irradiating the ultraviolet ray for excitation when the functional group having such polarity increases.

For example, an increase in the carbonyl group reduces the gap between HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital), resulting in a new low energy transition. .

  Further, not only C (carbon) atoms but also P (orbital) electrons may have p orbital electrons as well as O (oxygen) atoms and N (nitrogen) atoms. Therefore, a π bond can occur between these P orbital atoms. Among them, the C═O double bond mainly decreases LUMO largely because the interatomic polarization is relatively large. As a result, it becomes easier to absorb light having a longer wavelength than a substance composed of only hydrocarbon (CH). That is, the amount of fluorescence generated by ultraviolet irradiation increases.

Therefore, the measurement apparatus 100 is used to irradiate the object OBJ with ultraviolet light for excitation (
(UV irradiation) and detecting the fluorescence generated in the object OBJ upon receiving the ultraviolet rays, the state (wetting property) after the surface modification treatment on the object OBJ can be evaluated.

[B. Experimental example]
Hereinafter, changes in the amount of fluorescence measured when the inventors of the present invention perform surface modification using plasma treatment and corona treatment will be described.
(1. Plasma treatment)
Below, the measurement example at the time of applying the surface modification process using a plasma process with respect to PET film (film thickness: 25 micrometers) as target object OBJ is shown.

  FIG. 2 is a schematic diagram of an apparatus used for plasma processing. Referring to FIG. 2, plasma processing apparatus 200 includes planar electrodes 204 and 208 arranged to face each other at a predetermined interval. The planar electrode 204 is electrically connected to the AC voltage source 202. On the other hand, the planar electrode 208 is electrically connected to the ground 212. Therefore, a predetermined alternating electric field is generated in the space 214 between the planar electrode 204 and the planar electrode 208. When this alternating electric field becomes larger than the dielectric strength in the space 214, plasma is generated. It is preferable that the voltage value generated by the AC voltage source 202 can be arbitrarily changed within a predetermined range.

  The object OBJ is placed in the space 214, and the surface is irradiated with plasma. Dielectric materials 206 and 210 are disposed on the surfaces of the planar electrodes 204 and 208, respectively.

  In addition, the space 214 that is substantially sealed in a vacuum state (low pressure state) is also referred to as “vacuum plasma processing”, and the space 214 that is filled with a predetermined gas atmosphere is “atmospheric pressure plasma processing”. Also called.

  In this experimental example, a vacuum plasma processing apparatus (type: YHS-360) manufactured by Sakai Semiconductor Co., Ltd. is used, and a fluorescence sensor (model) manufactured by Sentech Co., Ltd. is used for measuring the amount of fluorescence generated from the object OBJ. : OL221) was used.

The surface modification treatment and the fluorescence amount measurement were batch treatment tests.
In the following table, the processing time of the vacuum plasma processing and the value of the fluorescence amount measured from the object OBJ after each processing are shown in association with each other. The fluorescence wavelength to be measured was 280 nm. In addition, the results of measuring the contact angle of the same object using a conventional droplet type measuring device are also shown.

  FIG. 3 is a diagram showing a graph plotting experimental results for plasma processing. As shown in FIG. 3, it can be seen that there is a strong correlation between the length of the plasma treatment time (degree of surface modification) and the measured fluorescence intensity. It can be seen from the relationship between the plasma processing time and the contact angle that the surface modification of the object OBJ proceeds as the processing time increases.

Here, the contact angle will be described with reference to FIG.
As shown in FIG. 4A, when a liquid dropped on an object (solid) is considered, in the liquid, a force is generated in a direction in which molecules are attracted and condensed by intermolecular force. As a result, in the liquid, a force (surface tension) that tends to be spherical with the smallest surface area is generated. At the interface between the liquid and the solid, the following relational expression is established among the surface tension γ _{S of} the solid, the surface tension γ _{L of} the liquid, and the interface tension γ _SL of the solid and the liquid.

γ _S = γ _L · cos θ + γ _SL (1)
In the equation (1), if θ is the contact angle and γ _S and γ _L are unchanged, the solid-liquid interfacial tension γ _SL is small (that is, the wettability is high). As shown in (b), the contact angle θ is small (that is, the value of cos θ is large).

On the other hand, as shown in FIG. 4C, when the interfacial tension γ _SL between the solid and the liquid is large (that is, when the degree of wettability is low), the contact angle θ is large (that is, the value of cos θ is Small).

Thus, in the conventional droplet type measuring device, the wettability is evaluated by measuring the contact angle.
(2. Corona treatment)
Next, a measurement example in the case where a surface modification treatment using corona treatment is applied to a PET film (film thickness: 25 μm) as the object OBJ will be described. In addition, as the object OBJ, two types were prepared, one that was subjected to silicon treatment as a pretreatment and the other that was not.

  FIG. 5 is a schematic diagram of a coating process including a corona treatment apparatus. Referring to FIG. 5, a process 300 includes a supply roller 302 for sequentially supplying a target object OBJ to be processed, and a winding roller 308 for winding the target object OBJ after processing. In between, the coater machine 310 and the corona treatment device 320 are arranged.

  The coater machine 310 includes a main roller 312 and a sub-roller 314. The coater machine 310 passes the object OBJ between both rollers, and continuously applies the coating agent 316 to one or both surfaces of the object OBJ.

  In the corona treatment device 320, an electrode group 324 for generating a corona discharge is disposed opposite to the surface of the main roller 322, and this electrode group 324 is electrically connected to a DC power supply unit 326 for supplying a high voltage. It is connected to the. An outer housing 328 is provided so as to cover the main roller 322 and the electrode group 324. The object OBJ is continuously transported by the transport roller 304 disposed in the front stage of the corona treatment device 320 and the transport roller 306 disposed in the rear stage of the corona processing device 320.

  In this experimental example, a comma coater (registered trademark) manufactured by Hirano Entec Co., Ltd. was used, and a corona treatment apparatus manufactured by Sophtal Co. was used. Then, a fluorescence sensor (model: OL221) manufactured by Sentech Co., Ltd. was used to measure the amount of fluorescence generated from the object OBJ.

  In addition, the surface modification treatment and the fluorescence amount measurement were conducted by a roll-to-roll method. The width of the object OBJ was 300 mm, and the coating width in the coater machine 310 was 280 mm. Moreover, the conveyance speed of the object OBJ was 6 m / min.

  In the following table, the voltage value used for corona treatment (corona discharge) and the display value of the fluorescence sensor when the object OBJ after each treatment is measured are shown in association with each other.

  (A) PET film (film thickness: 25 μm / no silicon treatment)

  (B) PET film (film thickness: 25 μm / with silicon treatment)

According to the measurement result described above, it can be seen that as the discharge voltage of the corona discharge by the corona treatment device 320 increases, more fluorescence is measured. That is, it is considered that the degree of surface modification of the object OBJ increases as the discharge voltage of the corona discharge increases. Therefore, the degree of surface modification (wetting) of the object OBJ and the measured fluorescence intensity. Can be said to have a strong correlation.
(Other)
In the above example, as a typical example of the object OBJ, an experimental example using a PET film has been shown. However, other materials, for example, a resin material such as plastic, an inorganic material such as glass and silicon, a metal material, etc. In addition, the measuring apparatus according to the present embodiment is applicable.

[C1. Configuration of measuring device (1)]
FIG. 6 is a schematic external view of the measuring apparatus 100 according to the embodiment of the present invention. FIG. 7 is a schematic diagram showing an optical structure of measuring apparatus 100 according to the embodiment of the present invention. FIG. 8 is a schematic diagram showing an electrical structure of measuring apparatus 100 according to the embodiment of the present invention.

  Referring to FIG. 6, measurement apparatus 100 includes a measurement processing unit 102 and an irradiation measurement head unit 104. As will be described later, the irradiation measurement head unit 104 includes an optical system for irradiating the object OBJ with ultraviolet rays and an optical system for detecting fluorescence generated in the object OBJ.

The measurement processing unit 102 is connected to the irradiation measurement head unit 104, gives an irradiation command of ultraviolet rays to the irradiation measurement head unit 104, and processes a signal indicating the fluorescence intensity detected in the irradiation measurement head unit 104. Output various information.

  As will be described later, in a usage pattern in which fluorescence is detected before and after the surface modification process is performed on the object OBJ, a plurality of irradiation measurement head units are provided for one measurement processing unit 102. 104 may be connected. For example, in the coating process shown in FIG. 5, the measurement points may be before and after the corona treatment.

  Referring to FIG. 7, the irradiation measurement head unit 104 includes a UV light emitting element 22 for generating ultraviolet rays, a dichroic mirror 24, a condenser lens 38, and a photodiode for detecting fluorescence from the object OBJ. 28. In the irradiation measurement head unit 104, the UV light emitting element 22, the dichroic mirror 24, and the condenser lens 38 are aligned on the optical axis Ax1. The ultraviolet light for fluorescence excitation generated in the UV light emitting element 22 propagates along the optical axis Ax1 through the condensing lens 38, and then condenses on the object OBJ arranged on the optical axis Ax1. In addition, it is preferable to set suitably the irradiation diameter (spot diameter) of the ultraviolet light for fluorescence excitation according to the range which wants to evaluate wettability among the target objects OBJ.

  For example, the UV light emitting element 22 according to the present embodiment generates ultraviolet rays having a main light emission peak of 365 nm. An ultraviolet lamp or the like may be used instead of the UV light emitting element 22 that is an ultraviolet LED.

  When the object OBJ is irradiated with ultraviolet rays, as described above, fluorescence is generated from the functional group on the surface. Most of the fluorescence generated by the object OBJ propagates on the same path (optical axis Ax1) as the excitation ultraviolet light in the direction opposite to the propagation direction of the excitation ultraviolet light and enters the dichroic mirror 24. .

  The dichroic mirror 24 is a kind of optical filter that changes its propagation direction according to the wavelength component of incident light. Specifically, when ultraviolet rays are incident along the optical axis Ax1, the dichroic mirror 24 transmits the incident ultraviolet rays while maintaining its propagation direction. On the other hand, when fluorescence (visible light) is incident along the optical axis Ax1, the dichroic mirror 24 changes its propagation direction by 90 ° and then exits from a different port. Typically, the reflecting surface of the dichroic mirror 24 is formed by metal deposition. As the dichroic mirror 24 according to the present embodiment, for example, ultraviolet light and fluorescence (visible light) can be separated by using a wavelength shorter than 410 nm as a transmission region and a wavelength longer than 410 nm as a reflection region. it can.

  Therefore, most of the fluorescence generated in the object OBJ propagates along the optical axis Ax1 from the left side of the drawing to the right side of the drawing, and then the propagation direction is bent downward by the dichroic mirror 24. Then, the fluorescence generated in the object OBJ propagates along the optical axis Ax2 from the upper side of the drawing to the lower side of the drawing and enters the photodiode 28.

  It is preferable that the distance L from the exit surface of the UV light emitting element 22 to the condenser lens 38 and the distance from the condenser lens 38 to the object OBJ are substantially the same.

  As described above, in the irradiation measurement head unit 104 shown in FIG. 7, the dichroic mirror 24 changes the propagation direction of the fluorescence received from the object OBJ, so that the excitation ultraviolet ray propagating on the same optical axis Ax1 The fluorescence to be detected can be separated. Therefore, even weak fluorescence generated from the object OBJ can be reliably detected.

Next, with reference to FIG. 8, the measurement processing unit 102 includes a CPU (Central Processing Unit) 40 that is a process execution subject, a display unit 42, a setting button 44, an oscillator 52, and a storage unit 5.
4, a power supply device 56, and an interface unit 58.

  The CPU 40 controls the entire measurement apparatus 100 by sequentially executing commands according to a program stored in advance. Specifically, the CPU 40 responds to the timing designated by the user and / or the transport position of the object OBJ, etc., and instructs the irradiation measurement head unit 104 to start irradiation with excitation ultraviolet rays. Based on a signal indicating the magnitude of fluorescence from the object OBJ detected by the irradiation measurement head unit 104, a value indicating wettability on the surface of the object OBJ (or a raw value of the detected fluorescence intensity) is obtained. Calculate and / or output.

  The display unit 42 includes, for example, a display such as an LCD (Liquid Crystal Display) or a CRT (Cathode-Ray tube), a segment display, or a notification unit such as a display lamp. As an example of the display unit 42 of the measurement processing unit 102, in the schematic diagram shown in FIG. 6, the segment display for displaying the detected fluorescence intensity and the value indicating the calculated wettability, and the state of the measurement apparatus 100 The LED display for showing etc. is illustrated.

  The setting button 44 includes instruction receiving means such as various switches and buttons. The setting button 44 accepts an operation by the user and outputs a command corresponding to the operation to the CPU 40. In the schematic diagram shown in FIG. 6, buttons for instructing change / reflection of settings and the like are illustrated.

The oscillator 52 generates an operation clock when the CPU 40 executes processing.
The storage unit 54 includes, for example, an E ² PROM (Electrically Erasable and Programmable Read Only Memory), and stores a program executed by the CPU 40 or C
A value indicating wettability calculated by the PU 40 and / or a value detected by the irradiation measurement head unit 104 are stored.

  The power supply device 56 receives the drive power supply Vcc and the like, and generates and supplies power having various voltage values required inside the measurement apparatus 100.

  The interface unit 58 mediates exchange of data with various devices outside the measuring apparatus 100. As an example, the interface unit 58 maintains compatibility with the conventional droplet method, which is calculated based on the determination output 46 indicating the quality of surface modification processing on the object OBJ and the amount of fluorescence from the object OBJ. A contact angle analog output 48 indicating the contact angle and a measurement start input 50 for instructing a measurement start from a user or the like are input / output. The determination output 46 and the contact angle analog output 48 will be described later.

  In this specification, “output” means displaying target information (data) on various display devices and notifying the user, and transmitting target information (data) to an external device. Including. Furthermore, “output” in this specification includes connecting the measuring apparatus 100 to a printer or the like and outputting a paper medium on which information is printed from the printer.

  The irradiation measurement head unit 104 includes a UV light projecting unit 1042 for irradiating excitation ultraviolet rays and a fluorescence light receiving unit 1041 for detecting fluorescence generated in the object OBJ.

  The UV light projecting unit 1042 includes a light projecting drive circuit 20 for driving the UV light emitting element 22 in addition to the UV light emitting element 22 described above. In addition to the drive power, the light projection drive circuit 20 is given a control signal from the CPU 40. When this control signal is activated (ON), power is supplied from the light projecting drive circuit 20 to the UV light emitting element 22, and the UV light emitting element 22 starts irradiating ultraviolet light for excitation.

The fluorescent light receiving unit 1041 includes an amplifier circuit 32 and an A / D converter 36 in addition to the photodiode (PD) 28 described above. The amplification circuit 32 amplifies the voltage signal output from the photodiode 28 (proportional to the magnitude of the detected fluorescence intensity) with a predetermined amplification factor, and the amplified signal is an A / D (Analog to Digital) converter. To 36. The A / D converter 36 quantizes the analog signal input from the amplifier circuit 32 to generate a digital signal, and outputs the generated digital signal to the CPU 40. The A / D converter 36 performs quantization using the reference voltage VREF supplied from the power supply device 56 as a voltage reference.

[C2. Configuration of measuring device (Part 2)]
If there is a light source (illumination device) including the same wavelength region as the fluorescence generated by the object OBJ in the installation environment of the measurement apparatus 100, the light from the light source (illumination device) can be a disturbance. Therefore, in order to suppress such disturbance, it is preferable to periodically change the intensity of the ultraviolet light for excitation (a kind of modulation).

  FIG. 9 is a schematic diagram showing an electrical structure of a measuring apparatus 100A according to a first modification of the embodiment of the present invention. The measurement apparatus 100A illustrated in FIG. 9 includes a UV light projecting unit 1044 that is changed to input a pulse signal having a predetermined cycle as a drive signal to the light projecting drive circuit 20 as compared with the measurement apparatus 100 illustrated in FIG. In addition to the adoption, a fluorescent light receiving unit 1043 to which an HPF (High Pass Filter) 30 and a disturbance light removal filter 34 are further added is adopted.

  That is, the UV light projecting unit 1044 irradiates the object OBJ with ultraviolet rays generated in response to a pulse signal (driving signal) given to the light projecting drive circuit 20 and whose intensity periodically changes. Is done. As a result, the fluorescence intensity generated in the object OBJ also changes with time in synchronization with the change period of the ultraviolet intensity.

  On the other hand, in the fluorescence light receiving unit 1043, when the fluorescence whose intensity changes with time is received by the photodiode 28, the detection result is input to the HPF 30, and the AC component included in the detection result is extracted. The extracted alternating current component is extracted by the disturbance light removal filter 34 with a period component substantially the same as the period (frequency) of the pulse signal applied to the light projecting drive circuit 20. More specifically, the disturbance light removal filter 34 sequentially calculates a correlation value between the AC component amplified by the amplifier circuit 32 and the periodic component included in the ultraviolet rays. This correlation value is a value indicating the intensity of fluorescence generated from the object OBJ.

  Then, the output signal (analog signal) from the disturbance light removal filter 34 is quantized by the A / D converter 36, whereby a digital signal is output.

  If it is known in advance that the light source (typically a fluorescent lamp) of the illuminating device that becomes a disturbance fluctuates in a specific cycle (for example, the frequency of a commercial power supply), the intensity of the ultraviolet light for excitation is reduced. The period to be changed is preferably shorter than such a fluctuation period.

  Since other configurations are the same as those of measurement apparatus 100 described with reference to FIGS. 7 and 8, detailed description thereof will not be repeated.

  As described above, according to the measuring apparatus 100A according to the first modification of the present embodiment, the fluorescence intensity generated from the object OBJ (the surface wettability is not affected by the disturbance from the light source in the installation environment). Value) can be measured stably.

[C3. Configuration of measuring device (Part 3)]
Depending on the surrounding environment (temperature, etc.) of the measuring apparatus 100, the case where the intensity of the ultraviolet ray for excitation irradiated from the irradiation measuring head unit varies can be considered. In this case, since the detected fluorescence intensity may be disturbed, it is desirable that the intensity of the ultraviolet rays applied to the object OBJ is constant. Below, in order to suppress such disturbance, the structure which maintains the ultraviolet-ray irradiated to the target object OBJ by monitoring the ultraviolet-ray intensity irradiated from an irradiation measurement head part is illustrated.

  FIG. 10 is a schematic diagram showing an electrical structure of a measuring apparatus 100B according to a second modification of the embodiment of the present invention. A measurement apparatus 100B illustrated in FIG. 10 further includes a light projection amount control circuit 21, a monitor photodiode (PD) 25, an amplification circuit 26, and an A / D converter 27, as compared with the measurement apparatus 100A illustrated in FIG. The UV light projecting unit 1046 that has been modified so as to be included is adopted.

  In the UV light projecting unit 1046, the monitor photodiode 25 is disposed adjacent to the irradiation surface of the UV light emitting element 22, and continuously detects the intensity of the ultraviolet light irradiated from the UV light emitting element 22 to the object OBJ. A voltage signal (proportional to the magnitude of the detected ultraviolet intensity) output from the monitor photodiode 25 is input to the amplifier circuit 26 and amplified at a predetermined amplification factor. The amplified voltage signal is quantized by the A / D converter 27 and applied to the CPU 40 as a digital signal.

  The CPU 40 generates a control command for the light intensity control circuit 21 by comparing the digital signal from the A / D converter 27 with a preset reference value. The light projection amount control circuit 21 adjusts the power supplied to the light projection drive circuit 20 in accordance with a control command from the CPU 40. As a result, the power supplied from the light projecting drive circuit 20 to the UV light emitting element 22 is feedback controlled. As a result, the intensity of the ultraviolet light for excitation irradiated from the UV light emitting element 22 to the object OBJ is kept constant.

  Since other configurations are the same as those of measurement apparatus 100 described with reference to FIGS. 7 and 8, detailed description thereof will not be repeated.

  Thus, according to measuring apparatus 100B according to the second modification of the present embodiment, it is possible to stably measure the fluorescence intensity (value indicating the wettability of the surface) generated from object OBJ.

[C4. Configuration of measuring device (4)]
In the example of the measurement apparatus described above, an optical system in which the ultraviolet ray for excitation and the fluorescence generated from the object OBJ propagate on the same optical axis is illustrated. On the other hand, the propagation path of ultraviolet light for excitation and the propagation path of fluorescence generated from the object OBJ may be different.

  FIG. 11 is a schematic diagram showing an optical structure of a measuring apparatus 100C according to a third modification of the embodiment of the present invention. In the measurement apparatus 100C shown in FIG. 11, the irradiation measurement head unit 104A includes a UV light projecting unit 1047 for irradiating excitation ultraviolet rays and a fluorescence light receiving unit 1048 for detecting fluorescence generated in the object OBJ. Including.

  The UV light projecting unit 1047 includes a UV light emitting element 22 and a condenser lens 38A. The UV light emitting element 22 and the condensing lens 38A are aligned on an optical axis Ax3 that forms a predetermined incident angle with respect to the object OBJ. Therefore, the ultraviolet light for excitation generated by the UV light emitting element 22 passes through the condenser lens 38A, propagates along the optical axis Ax3, and enters the object OBJ at a predetermined incident angle.

In the object OBJ, fluorescence generated at a reflection angle corresponding to the incident angle of ultraviolet light propagates. That is, with respect to the vertical axis of the object OBJ, the fluorescence generated in the object OBJ propagates along the optical axis Ax4 that is symmetric with the optical axis Ax3.

  In the fluorescence light receiving unit 1048, the wavelength filter 39, the condensing lens 38B, and the photodiode 28 are aligned on the optical axis Ax4. The wavelength filter 39 is an optical filter for suppressing excitation ultraviolet rays emitted from the UV light projecting unit 1047 from directly entering the photodiode 28. In other words, the wavelength filter 39 has a characteristic of transmitting when the fluorescence to be measured is incident, and cutting it when ultraviolet rays that are not the measurement object are incident.

  Therefore, the fluorescence generated in the object OBJ due to the irradiation of excitation ultraviolet rays passes through the wavelength filter 39, and is then collected by the condenser lens 38B and imaged by the photodiode 28. The photodiode 28 detects the intensity of the fluorescence generated from the object OBJ.

  Depending on the type of the object OBJ, when the wavelength of generated fluorescence differs, a plurality of UV light projecting units 1047 and / or fluorescent light receiving units 1048 are provided for each wavelength to be measured. Depending on the case, an appropriate one may be selected.

  Since other configurations are the same as those of the measurement apparatus described with reference to FIGS. 7 to 10, detailed description will not be repeated.

[C5. Configuration of measuring device (part 5)]
In the example of the measurement apparatus described above, the configuration for generating the ultraviolet light for excitation using the UV light emitting element which is an ultraviolet LED is exemplified, but an ultraviolet lamp or the like may be used. Hereinafter, in the configuration of the measuring apparatus shown in FIG. 11, a configuration in which an ultraviolet lamp is used as an ultraviolet ray generation source will be exemplified.

  FIG. 12 is a schematic diagram showing an optical structure of a measuring apparatus 100D according to a fourth modification of the embodiment of the present invention. FIG. 13 is a diagram showing an example of an emission spectrum of the ultraviolet lamp (metal halide lamp) shown in FIG. FIG. 14 is a diagram illustrating an example of characteristics of the wavelength filter illustrated in FIG.

  In the measurement apparatus 100D shown in FIG. 12, the irradiation measurement head unit 104B includes a UV light projecting unit 1045 for irradiating excitation ultraviolet rays and a fluorescence light receiving unit 1049 for detecting fluorescence generated in the object OBJ. Including. The configuration of the fluorescence light receiving unit 1049 is the same as that of the fluorescence light receiving unit 1049 shown in FIG.

  The UV light projecting unit 1045 includes an ultraviolet lamp 23, a condenser lens 38A, and a wavelength filter 39A. As the ultraviolet lamp 23, a metal halide lamp is typically used. The ultraviolet lamp 23, the condensing lens 38A, and the wavelength filter 39A are arranged in alignment on the optical axis Ax3 that forms a predetermined incident angle with respect to the object OBJ.

  As shown in FIG. 13, the ultraviolet lamp 23 irradiates ultraviolet rays over a relatively wide band, unlike the above-described UV light emitting element. Note that the light emitted from the ultraviolet lamp 23 may include a wavelength component in the visible light region. Therefore, it is necessary to extract only the ultraviolet component from the light including visible light emitted from the ultraviolet lamp 23 and irradiate the object OBJ. This is because when light containing a visible light component is irradiated, it is mixed with the fluorescence generated from the object OBJ, and the fluorescence intensity cannot be measured accurately.

  Therefore, in the UV light projecting unit 1045 of the measuring apparatus 100D, the wavelength filter 39A is arranged in the irradiation direction of the ultraviolet lamp 23, and only the ultraviolet component necessary for detecting the fluorescence intensity from the object OBJ is extracted. On the other hand, in the fluorescence light receiving unit 1049 of the measuring apparatus 100D, a wavelength filter 39B for selectively extracting only the fluorescence generated from the object OBJ is disposed.

  An example of the wavelength transmission characteristics of these wavelength filters 39A and 39B is shown in FIG. FIG. 14 shows an example of the case where the peak of the absorption spectrum of the functional group generated in the surface modification treatment in the object OBJ exists in the vicinity of 310 nm.

  In the example shown in FIG. 14, the wavelength filter 39A is composed of a bandpass filter (BPF) or a lowpass filter (LPF), transmits light in a wavelength band centered around 310 nm, and blocks other wavelength components. . That is, the wavelength filter 39A of the UV light projecting unit 1045 is intended to extract only the wavelength component corresponding to the absorption spectrum of the target functional group among the wavelength components generated from the ultraviolet lamp 23.

  On the other hand, the wavelength filter 39B of the fluorescence light receiving unit 1049 is composed of a high-pass filter (HPF) or a band-pass filter (BPF), and blocks components that may be disturbances other than fluorescence generated from a target functional group generated on the surface of the object OBJ. . In particular, it is intended to suppress the excitation ultraviolet light emitted from the UV light projecting unit 1045 from directly or indirectly entering the photodiode 28. Therefore, as shown in FIG. 14, the cutoff wavelength of the wavelength filter 39B of the fluorescence light receiving unit 1049 is set to a longer wavelength side than the transmission wavelength band of the wavelength filter 39A of the UV light projecting unit 1045.

  In the measuring apparatus 100D according to the fourth modification, the main wavelength component of the irradiated ultraviolet light can be adjusted by changing the wavelength filter 39A according to the type of functional group generated on the surface of the object OBJ. . Therefore, versatility can be improved as compared with the case where a UV light emitting element is used.

  Further, a plurality of wavelength filters 39A and 39B having different wavelength transmission characteristics are prepared, and according to the material of the target object OBJ (that is, the absorption wavelength of the functional group generated on the surface and the wavelength of the generated fluorescence). Thus, an appropriate wavelength filter may be selected.

  Since other configurations are the same as those of the measurement apparatus described with reference to FIGS. 7 to 11, detailed description will not be repeated.

[D1. Control structure (1)]
Next, a control structure in measuring apparatus 100 according to the present embodiment will be described.

FIG. 15 is a schematic diagram showing a control structure of measuring apparatus 100 according to the embodiment of the present invention. The control structure shown in FIG. 15 is basically applied to a measurement method for detecting the fluorescence intensity only after the surface modification process is performed on the object OBJ. That is, among the above experimental examples, as shown in the example of the corona treatment, it is suitable for a material that does not emit fluorescence from the surface until the surface modification treatment reaches a certain level. In other words, the control structure shown in FIG. 15 is used when evaluating an object OBJ whose fluorescence intensity before the surface modification treatment is zero.
Referring to FIG. 15, measuring apparatus 100 includes a buffer 400, a display data generation unit 402, a determination unit 404, a conversion unit 406, and a database 408 as its control structure. As an example, the measurement apparatus 100 outputs a determination output, a fluorescence intensity, and a contact angle by using a detection value (fluorescence intensity) detected by the irradiation measurement head unit 104 as an input.

  Typically, the display data generation unit 402, the determination unit 404, and the conversion unit 406 are realized by the CPU 40 executing a program, and the buffer 400 and the database 408 are realized in a predetermined area of the storage unit 54. .

  Specifically, in response to the measurement start trigger, the buffer 400 acquires and stores the detection value from the irradiation measurement head unit 104. In synchronization with this measurement start trigger, an irradiation command of ultraviolet rays is given to the irradiation measurement head unit 104. The detection values stored in the buffer 400 can be accessed from the display data generation unit 402, the determination unit 404, and the conversion unit 406, respectively. The buffer 400 may store the result of averaging values detected at a plurality of sample times. Furthermore, various preprocessing (filtering processing) for removing noise and the like may be performed.

  The display data generation unit 402 generates data for displaying the fluorescence intensity (detection value) stored in the buffer 400, typically a signal for driving the segment display.

  The determination unit 404 determines the wettability of the object OBJ based on the fluorescence intensity (detection value) stored in the buffer 400. Specifically, the determination unit 404 compares the fluorescence intensity value stored in the buffer 400 with a threshold value, and if the fluorescence intensity value is greater than the threshold value, secures a target wettability. Judge that it is done. This threshold value is set to a value corresponding to the required degree of wettability according to the manufacturing process of the object OBJ.

  Based on the fluorescence intensity (detection value) stored in the buffer 400, the conversion unit 406 calculates a value substantially equivalent to the contact angle calculated by the contact angle measurement device using the conventional droplet method. That is, assuming that the contact angle measurement device using the conventional droplet method is replaced with the measurement device 100 according to the present embodiment, the data interfaced with the management device is compatible. Is preferred. Therefore, the measuring apparatus according to the present embodiment prepares a table 410 (or a relational expression or a function) that associates the fluorescence intensity detected from the object OBJ with the contact angle at that time in the database 408. The conversion unit 406 refers to the corresponding table 410 and calculates the contact angle using the fluorescence intensity stored in the buffer 400. As shown in the above experimental results, the intensity of the generated fluorescence depends on the material of the object OBJ. Therefore, a plurality of tables 410 are prepared according to the material (type) of the object OBJ. It is preferable to selectively use the table 410 according to the material (type) of the object OBJ.

  FIG. 16 is a diagram showing a graph in which the experimental results shown in FIG. 3 are plotted with respect to the relationship between the contact angle and the fluorescence intensity. As shown in FIG. 16, it can be seen that there is also a strong correlation between the size of the contact angle and the fluorescence intensity. Therefore, a correspondence relationship as shown in FIG. 16 is experimentally acquired in advance, and the fluorescence intensity associated with the fluorescence intensity detected from the object OBJ is calculated with reference to this correspondence relationship.

  Here, a correspondence relationship as shown in FIG. 16 and a method of creating the table 410 shown in FIG. 15 will be described.

Basically, the surface modification treatment is performed on the target object OBJ under various conditions as in the above-described experimental example. In addition, about the target object OBJ, it is preferable to prepare a some sample with a homogeneous material. And with respect to the object OBJ after each surface modification process, while detecting the fluorescence intensity using the measuring apparatus which concerns on this Embodiment, a contact angle is measured using the conventional contact angle measuring apparatus. . As described above, with respect to the object OBJ that has been surface-modified so as to have a plurality of different wettability, the fluorescence intensity detected by the measurement apparatus 100 according to the present embodiment and the corresponding measurement value of the contact angle are associated with each other. Thereby, the correspondence (table 410) between the fluorescence intensity and the contact angle for the object OBJ can be generated.

[D2. Control structure (2)]
The control structure shown in FIG. 15 is suitable for a case where fluorescence is not substantially generated from the object OBJ before the surface modification treatment. On the other hand, among the above experimental examples, as shown in the plasma processing example, depending on the material of the object OBJ or the like, some fluorescence is emitted from the object OBJ even in the state before the surface modification process. May occur. In such a case, it is preferable to evaluate the wettability of the object OBJ based on the magnitude of the fluorescence intensity changed before and after the treatment.

  FIG. 17 is a schematic diagram showing a modification of the control structure of the measuring apparatus 100 according to the embodiment of the present invention. Referring to FIG. 17, the measurement apparatus 100 has buffers 411 and 412, a difference calculator 414, a display data generation unit 402, a determination unit 404, a conversion unit 416, and a database 408 as a modified control structure. Including.

  Typically, the display data generation unit 402, the determination unit 404, the conversion unit 416, and the difference calculator 414 are realized by the CPU 40 executing a program, and the buffers 411 and 412 and the database 408 are stored in the storage unit 54 as predetermined. Realized in the area.

  As an example, the measuring apparatus 100 detects the object OBJ based on the difference between the fluorescence intensity detected from the object OBJ before the surface modification process and the fluorescence intensity detected from the object OBJ after the surface modification process. The result (evaluation output, fluorescence intensity, contact angle, etc.) for evaluating the wettability is output.

  Specifically, the fluorescence intensity detected from the object OBJ before the surface modification processing is stored in the buffer 411 using the irradiation measurement head unit 104, and the buffer 412 is stored using the irradiation measurement head unit 104. The fluorescence intensity detected from the object OBJ after the surface modification treatment is stored. Note that the fluorescence intensity before and after the treatment may be detected using a single irradiation measurement head unit 104. However, as shown in FIG. It is preferable that the irradiation measurement head units 104 are arranged so that the fluorescence intensities detected by the two irradiation measurement head units 104 are stored in the buffers 411 and 412 respectively. In this case, it is necessary to perform calibration between the two irradiation measurement head units 104.

  The difference calculator 414 subtracts the detection value (before processing) stored in the buffer 411 from the detection value (after processing) stored in the buffer 412 to calculate a difference in fluorescence intensity.

  The display data generation unit 402 generates data for displaying the fluorescence intensity difference (fluorescence intensity change amount) calculated by the difference calculator 414, typically a signal for driving the segment display. .

  The determination unit 404 determines the wettability of the object OBJ based on the difference in fluorescence intensity calculated by the difference calculator 414. Specifically, the determination unit 404 compares the fluorescence intensity difference calculated by the difference calculator 414 with a threshold value. If the fluorescence intensity difference is greater than the threshold value, the target surface modification process is performed. Is determined to have been performed. This threshold value is set to a value corresponding to the required degree of surface modification treatment according to the manufacturing process of the object OBJ.

Similarly to the conversion unit 406 shown in FIG. 15, the conversion unit 416 is calculated by a contact angle measurement device using a conventional droplet method based on the fluorescence intensities (detection values) stored in the buffers 411 and 412 respectively. The contact angle substantially equivalent to the contact angle is calculated. Further, the conversion unit 416 takes the difference between the contact angles calculated from the respective detection values and outputs the amount of change in the contact angle. At this time, the conversion unit 416 reads the table 410 (or relational expression or function) in which the fluorescence intensity detected from the object OBJ and the contact angle at that time are associated with each other from the database 408, and calculates the contact angle. . Note that the conversion unit 416 may output the contact angle itself calculated before and after the surface modification process.

[E. Processing procedure]
Hereinafter, the procedure of the measurement process according to the present embodiment will be described.
(1. Wettability evaluation process (1))
FIG. 18 is a flowchart showing a procedure of wettability evaluation processing (No. 1) according to the embodiment of the present invention. The wettability evaluation process shown in FIG. 18 is executed corresponding to the control structure shown in FIG. 15, and is basically based only on the fluorescence intensity measured from the object OBJ after the surface modification process. Then, the wettability of the object OBJ is evaluated.

  First, in step S100, it is determined whether it is the measurement timing of the fluorescence intensity from the object OBJ. More specifically, when the surface modification process for the object OBJ is executed in batches, it is determined that the measurement timing is reached when the batch process is completed. Alternatively, when the surface modification process for the object OBJ is continuously performed, the measurement timing is determined every predetermined period.

  If it is not the measurement timing of the fluorescence intensity (NO in step S100), the process of step S100 is repeated.

  On the other hand, if it is the fluorescence intensity measurement timing (YES in step S100), the process proceeds to step S102. In step S102, a measurement start command is issued. In step S104, in response to the measurement start command, the irradiation measuring head unit 104 irradiates the object OBJ with excitation ultraviolet rays. In step S106, the irradiation measurement head unit 104 detects fluorescence generated in the object OBJ. In step S108, a noise removal process (filtering process) is performed on the detected fluorescence, and a fluorescence intensity (representative value) is acquired.

  In step S110, the acquired fluorescence intensity is compared with a threshold value to determine whether or not the wettability of the object OBJ is good. In subsequent step S112, a relational expression (table) corresponding to the type of the object OBJ is selected, and a contact angle corresponding to the acquired fluorescence intensity is calculated using the selected relational expression. That is, in step S112, a contact angle corresponding to the detected fluorescence intensity is calculated according to the selected correspondence among a plurality of correspondences acquired in advance for each type of object.

  In step S114, an output process is performed. Specifically, at least one of the fluorescence intensity acquired in step S108, the wettability determination result determined in step S110, and the contact angle calculated in step S112 is displayed or output to an external device. That is, in step S114, a value indicating the wettability on the surface of the object OBJ is output from the detected fluorescence intensity. At this time, the fluorescence intensity detected as a value indicating the wettability on the surface of the object OBJ is output.

In step S116, it is determined whether an instruction to end the wettability evaluation process is given. If the end of the wettability evaluation process is not instructed (NO in step S116), the processes in and after step S100 are repeated. On the other hand, if the end of the wettability evaluation process is instructed (
YES in step S116), the wettability evaluation process ends.

In the flowchart shown in FIG. 18, the processing in the case of calculating three results (fluorescence intensity, wettability determination result, contact angle) as the evaluation output is illustrated, but all these three results are calculated. There is no need to do so, and a necessary result may be appropriately selected according to the applied process. This also applies to the flowchart shown in FIG.
(2. Wettability evaluation process (2))
FIG. 19 is a flowchart showing a procedure of wettability evaluation processing (part 2) according to the embodiment of the present invention. The wettability evaluation process shown in FIG. 19 is executed corresponding to the control structure shown in FIG. 17, and basically the fluorescence intensity detected from the object OBJ before the surface modification process and the surface modification. The wettability of the object OBJ is evaluated based on the fluorescence intensity detected from the object OBJ after the quality treatment.

  First, in step S200, it is determined whether or not the measurement of the fluorescence intensity from the object OBJ before the surface modification process is instructed. If the measurement of the fluorescence intensity from the object OBJ before the surface modification process is not instructed (NO in step S200), the process of step S200 is repeated.

  If the measurement of the fluorescence intensity from the object OBJ before the surface modification process is instructed (YES in step S200), the process proceeds to step S202. In step S202, a first measurement start command is issued. In subsequent step S204, in response to the measurement start command, the irradiation measuring head unit 104 irradiates the excitation ultraviolet ray toward the object OBJ before the surface modification treatment. In step S206, the irradiation measurement head unit 104 detects fluorescence generated in the object OBJ. In step S208, a noise removal process (filtering process) is performed on the detected fluorescence, and a fluorescence intensity (representative value) for the object OBJ before the surface modification process is acquired.

  In subsequent step S210, a surface modification process is performed on the object OBJ. In step S212, it is determined whether or not an instruction to measure fluorescence intensity from the object OBJ after the surface modification process has been issued. If the measurement of the fluorescence intensity from the object OBJ after the surface modification process is not instructed (NO in step S212), the process of step S212 is repeated.

  If measurement of the fluorescence intensity from the object OBJ after the surface modification process is instructed (YES in step S212), the process proceeds to step S214.

  In step S214, a second measurement start command is issued. In subsequent step S216, in response to the measurement start command, the irradiation measuring head unit 104 irradiates the excitation ultraviolet ray toward the object OBJ after the surface modification treatment. In step S218, the irradiation measurement head unit 104 detects fluorescence generated in the object OBJ. In step S220, a noise removal process (filtering process) is performed on the detected fluorescence, and a fluorescence intensity (representative value) for the object OBJ after the surface modification process is acquired.

  In the continuous process as shown in FIG. 5, it is preferable to arrange the irradiation measurement head unit 104 at the front stage and the rear stage of the surface modification treatment. In this case, the first measurement start command is given to the irradiation measurement head unit 104 arranged before the surface modification process, and the second measurement start command is arranged after the surface modification process. The irradiation measurement head unit 104 is provided.

  Thereafter, in step S222, the difference between the fluorescence intensity acquired from the object OBJ before the surface modification process and the fluorescence intensity acquired from the object OBJ after the surface modification process is calculated. In the subsequent step S224, the difference in the calculated fluorescence intensity is compared with a threshold value to determine whether or not the wettability of the object OBJ is good.

  In step S226, a relational expression (table) corresponding to the type of the object OBJ is selected, and using the selected relational expression, the fluorescence intensity acquired from the object OBJ before the surface modification process and after the surface modification process. Two contact angles respectively corresponding to the fluorescence intensities acquired from the object OBJ are calculated. In subsequent step S228, a difference between the calculated two contact angles is calculated. The calculated difference in contact angle indicates the degree of improvement in wettability by the surface modification process.

  In step S230, output processing is performed. Specifically, at least one of the fluorescence intensity difference acquired in step S220, the wettability determination result determined in step S224, and the contact angle difference (change amount) calculated in step S228 is calculated. Display or output to external device. That is, wetting on the surface of the object OBJ based on the difference between the result of detecting the fluorescence generated in the object OBJ before the surface modification process and the result of detecting the fluorescence generated in the object OBJ after the surface modification process. A value indicating the sex is calculated. At this time, the fluorescence intensity detected as a value indicating the wettability on the surface of the object OBJ is output.

  In step S232, it is determined whether an instruction to end the wettability evaluation process is given. If the end of the wettability evaluation process is not instructed (NO in step S232), the processes in and after step S200 are repeated. On the other hand, if the end of the wettability evaluation process is instructed (YES in step S232), the wettability evaluation process ends.

[F. Application example]
You may adjust so that the fluctuation | variation which arises in a surface modification process may be suppressed based on the result in the above wettability evaluation processes. That is, various conditions in the surface modification treatment (plasma treatment or corona treatment) may be dynamically adjusted by feeding back the wettability evaluation result.

  FIG. 20 is a schematic diagram showing an example of a surface modification process 500 according to an embodiment of the present invention. FIG. 20 shows an example of atmospheric pressure plasma treatment as a typical example.

Referring to FIG. 20, the object OBJ is arranged on a transfer conveyor 502 that is a typical example of the transfer means, and is sequentially transferred from the right side to the left side of the drawing. The conveying conveyor 502 is given a driving force by driving rollers 504 and 506 or the like. The rotational speeds of these drive rollers 504 and 506 are controlled by a conveyor controller 508 or the like. The conveyor controller 508 is typically configured by a PLC (Programmable Logic Controller). The conveyor controller 508 adjusts the number of rotations of the drive rollers 504 and 506, that is, the moving speed of the conveyor, in accordance with a command from the measuring apparatus 100.

  In addition, a reactor 530 and a measuring apparatus 100 for performing plasma processing on the object OBJ are sequentially arranged from the upstream side of the transport conveyor 502.

A gas for forming a gas atmosphere for plasma treatment is supplied to the reactor 530 through a mixer 516 and a valve 518. The mixer 516 is connected to a cylinder 512 that holds oxygen and a cylinder 522 that holds argon gas. A valve 514 is provided in a path connecting the cylinder 512 and the mixer 516, and a valve 524 is provided in a path connecting the cylinder 512 and the mixer 516. The valves 514 and 524 can adjust the supply amounts of oxygen and argon, respectively. Therefore, the mixing ratio of the gas supplied to the reactor 530 is changed by adjusting the opening degree of the valves 514 and 524.

  The reactor 530 is supplied with a high-frequency voltage from a high-frequency power source 532, and plasma is generated when discharge occurs in a gas atmosphere. By this generated plasma, the surface modification process is performed on the object OBJ.

  The object OBJ after the surface modification treatment is moved to the position where the irradiation measurement head unit 104 is disposed, and then the irradiation measurement head unit 104 is irradiated with excitation ultraviolet rays, and the fluorescence intensity is detected. The The arrival of the object OBJ at the irradiation / measurement position of the irradiation measurement head unit 104 is detected by a sensor (not shown) or the like, and a measurement start command is issued in response to this detection.

  Based on the fluorescence intensity from the object OBJ detected by the irradiation measurement head unit 104, the measurement processing unit 102 evaluates the wettability of the object OBJ. In the measurement processing unit 102, a speed adjustment request is given to the conveyor controller 508 based on the wettability evaluation result. For example, according to the state of the object OBJ after the plasma processing by the reactor 530, it is determined whether the plasma processing time for each object OBJ should be longer or shorter. Based on this, the conveyance speed of the conveyance conveyor 502 is adjusted. That is, in the surface modification process 500, the wettability evaluation result of the object OBJ measured by the measuring device 100 is fed back, and the plasma treatment is maintained in an optimum state. As will be described later, various operation parameters may be dynamically adjusted in addition to the transport speed of the transport conveyor 502.

  Next, a method for dynamically adjusting operation parameters in the surface modification process as described above will be described.

  FIG. 21 is a flowchart showing the procedure for adjusting the surface modification process according to the embodiment of the present invention.

  Referring to FIG. 21, first, in step S300, the wettability evaluation result for the object OBJ is acquired using the wettability evaluation process as shown in FIG. 18 or FIG. In a succeeding step S302, it is determined whether or not the number of the objects OBJ for which the wettability evaluation result has been obtained exceeds a specified number. If the number of objects OBJ for which the wettability evaluation result has been acquired does not exceed the specified number (NO in step S302), the process of step S300 is repeated.

  That is, in steps S300 and S302, a statistically significant number of samples (wetability evaluation results) are acquired in order to observe the overall behavior in the target surface modification process.

  If the number of objects OBJ for which the wettability evaluation result has been acquired exceeds the specified number (YES in step S302), the process proceeds to step S304. In step S304, statistical processing is performed on the acquired wettability evaluation result. In the subsequent step S306, the tendency of variation in the target surface modification process is acquired based on the result of the statistical processing. For example, there is an overall tendency that the degree of surface modification of the object OBJ is excessive or the degree of surface modification is insufficient.

In step S308, the type of parameter to be adjusted and / or the amount of parameter change is determined based on the acquired tendency of the surface modification process. For example, when plasma treatment is adopted as the surface modification treatment as shown in FIG. 20, (a) the object O
BJ transport speed (that is, processing time), (b) gas mixture ratio, (c) gas flow rate, (d) power supply voltage of high-frequency power supply, (e) frequency of high-frequency power supply, and the like are parameters to be adjusted. When corona treatment is employed as the surface modification treatment, (f) corona treatment time, (g) corona generation voltage value, (h) conveyance speed of the object, and the like are parameters to be adjusted.

  For example, if the average value of the wettability values for the past five times is smaller than a predetermined threshold value, that is, if the calculated contact angle value is larger than a predetermined value, it is determined that the wettability has deteriorated. Then, the conveying speed of the object OBJ is slowed down and the processing time is made longer.

  In step S310, the determined parameter is changed by the determined change amount. Thereafter, the process in step S300 is repeated.

[F. Effect]
According to the measurement method according to the present embodiment, the object is irradiated with excitation ultraviolet light, and the wettability of the object is evaluated based on the fluorescence intensity generated by the irradiated ultraviolet light. In other words, the wettability of the object can be evaluated only by detecting the fluorescence generated almost simultaneously with the irradiation of excitation ultraviolet rays. Further, since it is only necessary to irradiate the object with ultraviolet light for excitation, it is possible to perform a nondestructive inspection that does not damage the object.

  Therefore, according to the present embodiment, the wettability of the surface of the object can be evaluated at high speed and non-destructively, which makes it suitable for in-line inspection.

  Further, according to the measurement method according to the present embodiment, the parameters of the surface modification treatment are dynamically adjusted based on the quality of the surface modification treatment and / or the degree of the effect of the surface modification treatment. You can also. Therefore, even if the result of the surface modification process deviates from the target state due to changes in the surrounding environment, variations in the object, etc., the operation can be performed while correcting the result.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

20 Light Emitting Drive Circuit, 21 Light Emitting Light Control Circuit, 22 Light Emitting Element, 24 Dichroic Mirror, 25 Monitor Photodiode, 26 Amplifying Circuit, 27 Converter, 28 Photodiode, 32 Amplifying Circuit, 34 Disturbance Light Rejecting Filter, 36 Converter, 38 , 38A, 38B Condensing lens, 39 Wavelength filter, 40 CPU, 42 Display unit, 44 Setting button, 46 Judgment output, 48 Contact angle analog output, 50 Measurement start input, 52 Oscillator, 54 Storage unit, 56 Power supply unit, 58 Interface unit, 100, 100A, 100B, 100C Measuring device, 102 Measurement processing unit, 104, 104A Irradiation measurement head unit, 200 Plasma processing device, 202 AC voltage source, 204 Planar electrode, 206 Dielectric, 208 Planar electrode, 212 Grand, 214 spaces, 300 professionals Set, 302 Supply roller, 304 Conveying roller, 306 Conveying roller, 308 Winding roller, 310 Coater machine, 312 Main roller, 314 Sub roller, 316 Coating agent, 320 Corona treatment device, 322 Main roller, 324 Electrode group, 326 DC Power supply unit, 328 outer casing, 400, 411, 412 buffer, 402 display data generation unit, 404 determination unit, 406 conversion unit, 408 database, 410 table, 414 difference calculator, 416 conversion unit, 500 surface modification process, 502 Conveyor, 504, 506 Drive roller, 508 Conveyor controller, 512, 522 Cylinder, 51
4,518,524 Valve, 516 Mixer, 530 Reactor, 532 High frequency power supply, 1041, 1043, 1048, 1049 Fluorescent light receiving unit, 1042, 1044, 1045, 1046, 1047 Projecting unit.

Claims (6)

Irradiating the object with ultraviolet rays;
Detecting fluorescence generated in the object;
Outputting a value indicating wettability on the surface of the object from the intensity of the detected fluorescence. The outputting step includes:
Calculating a contact angle corresponding to the intensity of the detected fluorescence according to the correspondence acquired in advance;
The method according to claim 1, further comprising a step of outputting the calculated contact angle.   The measurement method according to claim 2, wherein the correspondence acquired in advance is acquired for each type of object. Further comprising performing a surface modification process on the object;
The outputting step includes:
Based on the difference between the result of detecting the fluorescence generated in the object before performing the surface modification treatment and the result of detecting the fluorescence generated in the object after performing the surface modification treatment, The measurement method according to claim 1, further comprising a step of calculating a value indicating wettability on the surface of the object.   The measurement method according to claim 4, wherein the surface modification treatment includes treatment for generating at least one of a carboxyl group and a carbonyl group on the surface of the object. Irradiating the object with ultraviolet rays;
Detecting fluorescence generated in the object;
Outputting a fluorescence intensity detected as a value indicating wettability on the surface of the object.

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