JPS6017304A - Method for measuring thickness of thin film of insoluble liquid - Google Patents

Abstract

PURPOSE:To enable application of the same calibration curve even if a base material changes by correcting mutually the respective measurement signals for the light reflected from the base material alone and the transmitted and absorbed light and reflected light from the base material and an insoluble liquid and offsetting the absorption characteristic of the base material. CONSTITUTION:The IR light radiated from an IR emitting body 1 is transmitted alternately through the water provided on a chopper wheel 2, filters 4, 5 having absorption wavelength bands for ink and a filter 6 having a reference wavelength band and is projected to a measuring object (ink, water) 9 and an object to be measured (base material) 8. The reflected light is detected with an IR detecting element 11 and the signal VSG thereof is fed to a signal calculator 17 which processes the signals W', I' of the absorption wavelength bands of the water and the ink as well as the signal S' of the reference wavelength band together with the signals W0, I0 and S0 of only the object 8 stored therein and converts the same to the value D' of the object 9 alone. The equation [phiij][D]=[phiii(D')] is calculated by using the mutual influence function phiij between the respective values I, W, S determined by calibration and the film thickness and the film thickness mu of the ink and water is calculated by mu=phiii(D) from the value D of the ink and water alone existing mixedly in the object 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for measuring the thickness of a thin film of an insoluble liquid, and more particularly to a method of measuring the thickness of a thin film of an insoluble liquid, which can be applied to a method of measuring the thickness of a thin film of a mixture of ink and water in a printing press, etc. .

Measuring instruments such as infrared moisture meters are generally constructed from components similar to those shown in FIG. 1, for example. This configuration has the following problems.

■ Since the measurement wavelength band of infrared detection is used in the range of 1.0 to 2.0 μm, it is susceptible to changes in the color chart of the base material.

■ Ratio including base material and moisture content (moisture is evaluated using No. M, so if the base material is different, it is necessary to create a different calibration curve.

■ Separates the total amount of the mixed liquid containing moisture and ink adhering to the base material without contacting it.

could not be extracted at the same time.

The present invention was developed in view of the above circumstances, and its purpose is to quantitatively measure the entire thin film thickness of an insoluble liquid, such as a mixture of water and ink, online, and to An object of the present invention is to provide a method for measuring a thin film thickness of an insoluble liquid, which can be used to separate and measure ink and the like.

In the method for measuring the thickness of an insoluble liquid coated on a base material according to the present invention, a measurement wavelength band is provided in the absorption wavelength band of the insoluble liquid.

A reference wavelength band is provided outside the absorption wavelength band, the source of each reflected light from the base material in each of these wavelength bands is determined, and each transmitted absorption light or reflected light from the base material and the insoluble liquid is measured. , is characterized in that the absorption characteristics of the base material are offset by mutually proportional correction of each of these measurement signals, and the color of the base material can be adjusted by setting the measurement wavelength band in the range of 3.0 to 4.5 μm, for example. In addition, by treating each measurement signal as a normalized signal, it is possible to cancel out the signal of the base material, so that the same calibration curve can be applied even if the base material changes. When it is known that the content of an insoluble liquid is composed of ink and water, such as in printing, it is possible to separate the normalized signal into individual signals of ink and water.

An embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing the configuration of an embodiment used to carry out the method of the present invention.

2 and 3 are signal waveform diagrams each illustrating the entire operation of the embodiment shown in FIG. 1.

FIG. 4 is a flowchart showing the operation of the embodiment shown in FIG. 1.

FIGS. 5 and 6 are diagrams each showing an example of actual measurement according to the embodiment shown in FIG. 1. FIG.

In FIGS. 1 to 4, I is an infrared emitter, 2°Zα is an infrared transmitting lens, and 3 is a chopper wheel.

d, 5.6 is an infrared interference filter, and 2 is an infrared light pipe.

8 is the object to be measured (base material), 9 is the object to be measured (ink,
water), ZZ is an infrared detection element, 12 is an amplifier, 13.14
is a pulse detector, I5 is a synchronizer, I6 is a converter, I
7 is a signal calculator, 18 is a display, Tr is a pulse, V2O is an analog signal, t is time, H is a sampling period, W is a signal in the absorption wavelength band of water, S is a signal in the reference wavelength band, φ is a mutual influence function, R is a measurement signal consisting of I, Q or water components, and D is a signal value of ink or water alone.

Value (8o8oW This is the moisture content of I4 main ink or mixture.

In FIG. 1, infrared light emitted from an infrared emitter 2 is focused into an infrared light conduit 2 by an infrared transmitting lens 2 . During this time, infrared interference filters 4, 5, and 6f are provided on the chopper wheel 3, including a filter 4 for the water absorption wavelength band and a filter 5 for the ink absorption wavelength band. The reference wavelength band filters 6 alternately transmit light in that wavelength band.

This infrared light is measured by the infrared leading tube 2 and the pair 12! p:49
The light is guided and projected onto the object to be measured 8. Infrared absorption and reflection occur in the measurement object 9 and the measurement object 8, and the reflected light is collected by the infrared transmission lens 10 and guided to the infrared detection element rr, and depending on the intensity of this infrared light, Infrared detection element II
The resistance changes and the voltage is amplified and converted by the amplifier 12.
This signal is the analog signal V8() shown in Figures 2 and 3.

On the other hand, a pulse detector 14 detects the rotational position of the infrared interference filter 4j5.6 provided on the chopper wheel 3.
and a pulse detection unit 1 that detects the measurement position of the object to be measured 8.
The output signal of the synchronizer I5 for synchronizing the pulse signals starting from 3 is the trigger pulse Tr shown in FIGS. 2 and 3. Each of this trigger pulse Tr and analog signal Vsa.

It is synchronously adjusted to the peak of the signal W in the water absorption wavelength band, the signal operator in the ink absorption wavelength band, and the signal S in the reference wavelength band.
The A/D converter Z6 receives the signal of the trigger pulse Tr, takes in each of W, I, and 8 of the analog signal V8G, is sent to the signal calculator Z2, calculates the ink film thickness and its moisture content, and displays it on the display I8. It is now displayed.

Next, the configuration in which signals are processed by the signal calculator 12 will be explained with reference to FIG. 4. In the analog signal VSG of only the object to be measured 8 in FIG. 3, a signal W in the absorption wavelength band of water has one period H. and outside the absorption wavelength band of the ink. and reference wavelength band signal S
o'1. Import and store it in memory, set it for measurement of the object to be measured 8 and the object to be measured 9 in Fig. 2, and record the signal W in the water absorption wavelength band of the analog signal VSG, the signal W in the ink absorption wavelength band, and the reference wavelength. The band signal s'6 was captured and stored W,,I. -8ok, both are processed and the value of only the measurement object 9 is converted to the public value.

Here, in advance, calculate the relationship between each value I, W, S of the analog signal VEIG due to the ink and water film thickness and the film thickness, and calculate the value of the ink and water alone mixed in the measurement object 9. Calculate Di.

From the individual value and mutual influence function φ, μ=φ1l (D)
The ink/water film thickness μ is calculated from , and the water content G is obtained. The processing configuration is such that the film thickness μ and water content G are displayed on the display I8, and the series of steps is completed.

The method according to one embodiment of the present invention will be explained.

■ Wo, I of the analog signal VSG of the object to be measured 8
. , So, W of the analog signal VSG including the object to be measured 8 and the object to be measured 9, 1. SL=signal value based on beans and composed of ink components. By converting the signal value consisting of T and the water component to ÷τ÷, the signal can be normalized and only the measurement object 9 can be extracted. For example, signal values consisting of ink components can be handled in the same way. This method of extracting the single signal value is displayed by the following effect, that is, 6 signals■. #I, Wo, w, So #S
By converting them into proportional signals, only the object 9 to be measured is extracted.

■ As a method of extracting the independent components of ink and water in the measurement object 9, that is, the insoluble substance, the measurement subscript I...Ink, 2...Water One balance relational expression in this equation is fully satisfied. When extracted and transformed, it is expressed as φ+t (-LLi>-φxscDx)=0 L φth (D2). In this relationship, if water soaks into the ink, the water has no effect on the ink, so when =1, the film thickness is φ and 2.

The ink-only signal value becomes D1. On the other hand, a place with only water -L→-
”-, φ1, (Di)=O and φ1. (8° completed)=φ,
2 (D2), and the water alone signal (i1\Dat converted film thickness means the apparent ink film thickness when water interferes with the ink, and in order to offset this, ,
The influence function φ
1, water interferes with the ink signal s01, which is balanced by the apparent ink film thickness.

If we calculate all of this equation, we can extract the ink and water separately.

Next, a specific example of actual measurement conducted using the above-described method of the present invention will be shown.

FIG. 5 shows an example of the mutual influence function φ, 1 when the object to be measured is plated with Cu and Cr. As shown in FIG. 5, it can be seen that the influence function φ2□ does not reverse even if the object to be measured is different, and is a stable test line.

Figure 6 shows an example in which the ink rollers on the printing press were measured using 1- rollers, and it can be seen that the ink and water were completely separated in the measurement.

As described above, the method of the present invention provides the following advantages.

■ Conventionally, calibration work was required each time the object to be measured changed, but with the uninvented method, only 6 signal work is required. ,I,Wo,W,Bo.

Since only the object to be measured is extracted by mutually converting S into a ratio signal, it can be used even if the value of the object to be measured is changed in the second calibration operation.

(2) In the insoluble liquid analogy, the measurement signal of the object to be measured is separated by the balance relationship and mutual influence function of ink and water, and its single signal value, D, is obtained.

That is, it is possible to separate the mixed state of ink and water and measure the individual film thickness of ink and water.

(2) High-quality printed matter can be obtained by applying the method of the present invention to, for example, an offset printing press and quantitatively measuring the amount of ink or water per drop online.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram illustrating an embodiment used to carry out the method of the present invention. 2 and wJ3 are signal waveform diagrams each explaining the operation of the embodiment shown in FIG. 1, and FIG. d54 is a flow chart diagram showing the operation of the embodiment shown in FIG. 1. FIGS. 5 and 6 are diagrams each showing an example of actual measurement according to the embodiment shown in FIG. 1. FIG. I... Infrared light emitter, 2.10... Infrared transmitting lens,
3... Chopper wheel %4.5.6... Infrared interference filter, ? ... Infrared leading tube, 8... Object to be measured (base material), 9... Object to be measured (ink, water). ZZ... Extra detection purple, 12... Amplifier, Z 3
, I4...Pulse detector, I5...Synchronizer, I6
...A/D converter, I2...Signal calculator, 1B...
·display. Applicant Sub-Agent Patent Attorney Takehiko Suzue Day 1 Day 20 Figure 3 4? oi caseQ

Claims (1)

[Claims] In a method for measuring the thickness of an insoluble liquid deposited on a base material, a measurement wavelength band is provided in the absorption wavelength band of the insoluble liquid, a reference wavelength band is provided outside the absorption wavelength band, and these wavelength bands are provided. Each reflected light from the base material in each wavelength band was measured, and each transmitted absorption light or reflected light from the base material and the insoluble liquid was measured. A method for measuring a thin film thickness of an insoluble liquid, characterized in that the absorption characteristics of the base material are offset by mutually proportional correction of each of these measurement signals.