Liquid matter assessment method and liquid matter assessment device

Abstract

A liquid matter assessment method according to the present invention is for assessing a liquid matter containing at least a solvent, a resin, and a non-reactive additive. The non-reactive additive is a fluorescent marker compound. The method comprises: a fluorescent spectrum observation step for acquiring a fluorescent spectrum in an arbitrarily defined excitation wavelength of the liquid matter; and a spectrum analysis step for acquiring data pertaining to a peak intensity shift degree from the acquired fluorescent spectrum on the basis of an interaction between the fluorescent marker compound and an object to be tested in the liquid matter.

Description

Liquid substance evaluation method and liquid substance evaluation device

[0001] The present invention relates to a method and an apparatus for evaluating a liquid material, and in particular to a method and an apparatus for evaluating a liquid material that can constantly detect minute fluctuations in the water content, impurities, etc. in the liquid material without using a reactive fluorescent marker agent.

[0002] In recent years, the range of applications for optical films has expanded, including polarizer protective films and retardation films for display devices such as liquid crystal displays and organic electroluminescent displays, substrate films for touch panels and gas barrier substrate films, as well as substrate films for nanoimprinting and flexible electronic circuits. This has created a demand for a stable supply of high-quality optical films, such as those with high transparency and functionality. Here, a known process for producing resin molded products involves dissolving a resin in a solvent and adding functional additives to obtain the desired product, due to its high processability. While intermediate products are composed of resin, additives, and solvent, their quality is affected by lot variations resulting from differences in suppliers. Furthermore, in factories, minute impurities can be introduced during storage or when the product is introduced into piping, affecting product quality.

[0003] As evaluation systems for monitoring variations such as variations in quality, Patent Documents 1 and 2 disclose methods for quantifying trace impurities in a sample by adding a fluorescent substance as a medium and causing the fluorescent substance to react. Patent Document 3 also discloses a moisture detection method using a fluorescent substance that indirectly emits fluorescence by reacting directly with water to generate hydrogen peroxide.

[0004] However, in the techniques disclosed in Patent Documents 1 to 3, a reactive fluorescent marker agent is used to detect the fluorescence information of impurities and detect fluctuations in the object being inspected. In other words, the added fluorescent marker compound itself becomes an impurity after reaction, which reduces the performance of resin molded products such as films, making it unsuitable for the quality of modern optical films.

[0005] JP 2001-56327 A JP 2011-95111 A International Publication No. 2029 / 039963

[0006] The present invention has been made in consideration of the above problems and circumstances, and its problem to be solved is to provide a method and device for evaluating liquid materials that can constantly detect minute fluctuations in the water content, impurities, etc. in liquid materials without using a reactive fluorescent marker agent.

[0007] In order to solve the above-mentioned problems, the present inventors investigated the causes of the above-mentioned problems and discovered that by adding a fluorescent marker compound to a liquid as a non-reactive additive and measuring the amount of change in the peak intensity of the fluorescence spectrum of the liquid, it is possible to constantly detect minute fluctuations in the water content, impurities, etc. in the liquid without using a reactive fluorescent marker agent, and thus arrived at the present invention. That is, the above-mentioned problems of the present invention are solved by the following means.

[0008] 1. A method for evaluating a liquid material containing at least a solvent, a resin, and a non-reactive additive, wherein the non-reactive additive is a fluorescent marker compound, the method comprising: a fluorescence spectrum observation step of acquiring a fluorescence spectrum of the liquid material at an arbitrary excitation wavelength; and a spectrum analysis step of acquiring data on a peak intensity shift degree from the acquired fluorescence spectrum based on an interaction between the fluorescent marker compound in the liquid material and an object to be tested.

[0009] 2. The method for evaluating a liquid substance according to Item 1, wherein the difference in solubility parameter ΔSP between the fluorescent marker compound and the test object in the liquid substance is within a range of 6 to 22.

[0010] 3. The method for evaluating a liquid material according to item 1 or 2, wherein the non-reactive additive is contained in the liquid material in an amount ranging from 1 to 5,000 ppm by mass.

[0011] 4. The method for evaluating a liquid substance according to any one of items 1 to 3, wherein the spectral analysis step is performed in-line.

[0012] 5. The method for evaluating a liquid substance according to any one of Items 1 to 4, further comprising a data processing step of calculating an amount of the substance to be inspected using a calibration curve based on peak intensities included in the data relating to the degree of peak intensity shift.

[0013] 6. An apparatus for evaluating a liquid material containing at least a solvent, a resin, and a non-reactive additive, wherein the non-reactive additive is a fluorescent marker compound, the apparatus comprising: a fluorescence spectrum observation unit that acquires a fluorescence spectrum of the liquid material at an arbitrary excitation wavelength; and a spectrum analysis unit that acquires data on a peak intensity shift degree from the acquired fluorescence spectrum based on an interaction between the fluorescent marker compound in the liquid material and an object to be inspected.

[0014] 7. The liquid material evaluation device according to claim 6, further comprising a data processing unit that calculates the content of the test object using a calibration curve based on the peak intensity included in the data relating to the peak intensity shift degree.

[0015] 8. The liquid material evaluation device according to item 6 or 7, further comprising an information display unit that displays data relating to the peak intensity shift degree.

[0016] The above-mentioned means of the present invention make it possible to provide a liquid evaluation method and a liquid evaluation device that can constantly detect minute fluctuations in the water content, impurities, etc. in liquid materials without using a reactive fluorescent marker agent.

[0017] Although the mechanism of action or manifestation of the effects of the present invention is unclear, we speculate as follows. For example, we believe that variations in film quality (haze) are due to the following variations: (i) differences in impurities and stabilizers present during the production of delivered raw materials; (ii) differences in the moisture content of resins and additives or the pH of solvents during film production due to seasonal variations during storage; and (iii) differences in the degree of deterioration of piping due to differences in piping equipment between factories and differences in aging since the factory was built, resulting in the leakage of metal ions. Therefore, to detect such variations without adding reactive fluorescent marker agents that cause performance degradation, we added a non-reactive additive (non-reactive fluorescent marker compound) to a liquid containing raw materials and solutes and measured its fluorescence spectrum. Furthermore, we prepared the liquids described in (i) to (iii) above, measured the fluorescence spectrum of each liquid, and compared it with the fluorescence spectrum of a reference sample. We found that the peak intensity of the non-reactive fluorescent marker compound shifted. Here, the reasons why this high-precision evaluation method, which does not involve chemical reactions between the resin, non-reactive fluorescent marker compound, and the test object, was possible are as follows. When a liquid contains only two components, the unreacted fluorescent marker compound and the test object, the density increases when the resin is added to the liquid, making intermolecular interactions more likely to occur. Furthermore, we believe that the interaction between the resin and the test object makes it possible to indirectly detect even the smallest signal from the unreacted fluorescent marker compound. Furthermore, the amount of information obtained from the signals of the unreacted fluorescent marker compound, the test object, and the resin at multiple wavelengths increases compared to when a single wavelength is used, making it easier to capture changes in fluorescence intensity.

[0018] As described above, by adding a fluorescent marker compound to a liquid as a non-reactive additive and measuring the amount of change in the peak intensity of the fluorescence spectrum of the liquid, minute fluctuations in the water content, impurities, etc. in the liquid can be constantly detected without using a reactive fluorescent marker agent. As a result, since the minute fluctuations can be detected in real time, the time required for feedback in the manufacturing process can be significantly reduced, and manufacturing efficiency can be improved.

[0019] FIG. 1 is a diagram schematically illustrating an example of the configuration of a liquid material evaluation device of the present invention. FIG. 2 is a flowchart illustrating a computer-controlled procedure executed by the liquid material evaluation device of the present invention. FIG. 3 is a diagram schematically illustrating an example of a dope preparation step, a casting step, a drying step, and a winding step in a solution casting film-forming method. FIG. 4 is a schematic diagram illustrating an example of a hard coat layer forming device.

[0020] The method for evaluating a liquid material according to the present invention is a method for evaluating a liquid material containing at least a solvent, a resin, and a non-reactive additive, wherein the non-reactive additive is a fluorescent marker compound, and the method comprises: a fluorescence spectrum observation step of acquiring a fluorescence spectrum of the liquid material at an arbitrary excitation wavelength; and a spectrum analysis step of acquiring data on a peak intensity shift degree from the acquired fluorescence spectrum based on an interaction between the fluorescent marker compound in the liquid material and an object to be tested. This feature is a technical feature common to or corresponding to each of the following embodiments.

[0021] In an embodiment of the present invention, it is preferable that the difference in solubility parameter ΔSP between the fluorescent marker compound and the test object in the liquid is within a range of 6 to 22, since this facilitates interaction between the fluorescent marker compound and the test object, making it easy to obtain the degree of peak intensity shift, and also makes it easy to obtain transparency in a product using the liquid.

[0022] In addition, it is preferable that the non-reactive additive is contained in the range of 1 to 5000 ppm by mass relative to the liquid material, in order to achieve both the haze of an optical film using the liquid material and the measurement sensitivity of the fluorescence spectrum.

[0023] Furthermore, performing the spectral analysis process inline is preferable in that it allows real-time detection of the moisture content in the liquid or the presence of impurities, significantly reducing the time required for feedback in the manufacturing process and improving manufacturing efficiency.

[0024] Furthermore, it is preferable to provide a data processing step in which the content of the test object is calculated using a calibration curve based on the peak intensity contained in the data relating to the peak intensity shift degree, as this allows for detecting fluctuations in the content of the test object and is therefore advantageous in terms of improving manufacturing efficiency.

[0025] The evaluation device of the present invention is an evaluation device for a liquid containing at least a solvent, a resin, and a non-reactive additive, wherein the non-reactive additive is a fluorescent marker compound, and the evaluation device includes a fluorescence spectrum observation unit that acquires a fluorescence spectrum of the liquid at an arbitrary excitation wavelength, and a spectrum analysis unit that acquires data on the degree of peak intensity shift from the acquired fluorescence spectrum based on the interaction between the fluorescent marker compound in the liquid and an object to be tested, thereby making it possible to constantly detect minute fluctuations in the water content, impurities, etc. in the liquid without using a reactive fluorescent marker agent.

[0026] Furthermore, it is preferable that the evaluation device of the present invention includes a data processing unit that calculates the content of the test object using a calibration curve based on the peak intensity included in the data regarding the peak intensity shift degree, and an information display unit that displays the data regarding the peak intensity shift degree.

[0027] The present invention, its components, and embodiments and modes for carrying out the present invention will be described below. In this application, the symbol "to" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0028] [Overview of the Liquid Material Evaluation Method of the Present Invention] The liquid material evaluation method of the present invention is a method for evaluating a liquid material containing at least a solvent, a resin, and a non-reactive additive, wherein the non-reactive additive is a fluorescent marker compound, and includes a fluorescence spectrum observation step of acquiring a fluorescence spectrum of the liquid material at an arbitrary excitation wavelength, and a spectrum analysis step of acquiring data on a peak intensity shift degree from the acquired fluorescence spectrum based on an interaction between the fluorescent marker compound in the liquid material and a test object. Furthermore, the liquid material evaluation method of the present invention preferably includes a data processing step of calculating the content of the test object using a calibration curve based on the peak intensities included in the data on the peak intensity shift degree, which makes it possible to detect fluctuations in the content of the test object and improves production efficiency.

[0029] In the present invention, the term "liquid" refers to a substance containing at least a solvent, a resin, and a non-reactive additive, and having a residual solvent content of 1,000 ppm by mass or more. Specific examples of such liquids include dopes for forming optical films, adhesives for bonding optical films to polarizers, coating solutions for forming hard coat layers to protect films, coating solutions for forming antistatic layers, aqueous coating solutions used to form near-infrared reflective films (e.g., coating solutions for forming high refractive index layers and low refractive index layers), and residual solvents after application of these coating solutions, coating materials for applying to products used in ink applications, electrolytes in batteries, coating solutions for protecting positive electrode active materials, coating solutions for coating automotive parts, engine oils, photosensitive materials before UV curing in the semiconductor field, and solutions containing polymers such as gelatin in the food field. Details of the dopes, coating solutions for forming hard coat layers, coating solutions for forming antistatic layers, and coating solutions for forming high refractive index layers and low refractive index layers will be described later.

[0030] In the present invention, the term "non-reactive additive" refers to a compound that does not form a covalent or ionic bond (does not undergo structural changes) with at least the test object. However, the non-reactive additive of the present invention is a compound that can change the degree of peak intensity shift through interactions with the test object, such as hydrogen bonds or van der Waals forces. Specifically, the non-reactive additive is preferably a compound that does not have a single wavelength absorption in the visible light region, as this prevents the liquid from becoming colored, making it suitable for use in the optical region. Examples of non-reactive additives include non-reactive fluorescent marker compounds. Furthermore, any non-reactive fluorescent marker compound that emits fluorescence may be used, including antioxidants, dyes, retardation adjusters, wavelength adjusters, size adjusters, and compounds with additive-derived functions.

[0031] As the antioxidant (AO agent), commonly known compounds can be used, and lactone-based, sulfur-based, phenol-based, double bond-based, hindered amine-based, and phosphorus-based compounds can be particularly preferably used. As the phenol-based compound, compounds having a 2,6-dialkylphenol structure are preferred, and examples thereof include "Irganox 1076" and "Irganox 1010" commercially available from BASF Japan Ltd., and "ADEKA STAB AO-50" commercially available from ADEKA Corporation.

[0032] Examples of the dye include compounds having an absorption wavelength in the near-infrared region and compounds having an absorption wavelength in the near-ultraviolet region. From the viewpoint of spectral characteristics, it is preferable to add at least one near-infrared absorption regulator having an absorption maximum wavelength in the wavelength range of 650 to 800 nm to the compound having an absorption wavelength in the near-infrared region (also referred to as a "near-infrared absorbing composition") as an additive for adjusting the absorption waveform. The near-infrared absorption regulator used in the present invention is preferably a near-infrared absorbing dye having an absorption maximum wavelength in the wavelength range of 650 to 800 nm. Examples of near-infrared absorbing dyes (NIR dyes) suitable for the present invention include cyanine dyes, squarylium dyes, croconium dyes, azo dyes, anthraquinone dyes, naphthoquinone dyes, phthalocyanine dyes, naphthalocyanine dyes, quaterrylene dyes, and dithiol metal complex dyes. Among these, cyanine dyes and squarylium dyes are preferred, with squarylium dyes being particularly preferred, from the viewpoint of detecting changes in fluorescence intensity in response to fluctuations in the test object.

[0033] From the viewpoint of spectral characteristics, it is preferable to add at least one near-ultraviolet absorption regulator having an absorption maximum wavelength in the wavelength range of 300 to 400 nm to the compound having an absorption wavelength in the near-ultraviolet region (also referred to as a "near-ultraviolet absorbing composition") as an additive for adjusting the absorption waveform. The near-ultraviolet absorption regulator used in the present invention is preferably a near-ultraviolet absorbing dye having an absorption maximum wavelength in the wavelength range of 300 to 400 nm. Examples of near-ultraviolet absorbing dyes (NUV dyes) suitable for the present invention include merocyanine dyes, benzotriazole UV absorbers, benzophenone UV absorbers, salicylate UV absorbers, cyanoacrylate UV absorbers, triazine UV absorbers, oxanilide UV absorbers, nickel complex UV absorbers, and inorganic UV absorbers. Among these, merocyanine dyes are particularly preferable from the viewpoint of detecting changes in fluorescence intensity in response to fluctuations in the test object.

[0034] The "resin" in the present invention can be appropriately changed depending on the application of the liquid material, and may be a thermoplastic resin or a thermosetting resin. Specific examples include cycloolefin resin (COP resin), triacetyl cellulose resin (TAC resin), acrylic resin, urethane resin, polyvinyl alcohol resin, and polyimide resin.

[0035] The "solvent" in the present invention can be appropriately changed depending on the application of the liquid, and examples thereof include organic solvents, water, etc. Examples of organic solvents include, as will be described later, chlorine-based solvents such as chloroform and dichloromethane; aromatic solvents such as toluene, xylene, benzene, and mixed solvents thereof; alcohol-based solvents such as methanol, ethanol, isopropanol, n-butanol, and 2-butanol; methyl cellosolve, ethyl cellosolve, butyl cellosolve, dimethylformamide, dimethyl sulfoxide, dioxane, cyclohexanone, tetrahydrofuran, acetone, methyl ethyl ketone (MEK), ethyl acetate, and diethyl ether. These solvents may be used alone or in combination of two or more.

[0036] In the present invention, the term "test object" refers to element ions and charged compounds (ionic compounds and polar compounds), and when these charged element ions or compounds are mixed into the liquid, they cause an interaction between the non-reacted additive and the test object, and they play a role in changing the degree of peak intensity shift of the non-reacted additive. In other words, the test object refers to a compound that causes a change in fluorescence intensity at the excitation wavelength and fluorescence wavelength at the maximum fluorescence intensity in the fluorescence spectrum obtained by exciting the non-reacted additive at an arbitrary excitation wavelength using a spectrofluorometer and measuring part or all of the fluorescence wavelengths from 250 to 950 nm.

[0037] Suitable test objects for the present invention include water, lithium, sodium, potassium, magnesium, calcium, strontium, or metal ions such as chromium, iron, and copper, halogen element ions such as fluorine, chlorine, and bromine, benzene, acetone, ethanol, methanol, and formamide.

[0038] In the present invention, the "degree of peak intensity shift" refers to the amount of change in the fluorescence wavelength and fluorescence intensity of the peak characteristic of a non-reacted additive (fluorescent marker compound) that varies depending on the amount of change in the test object in the liquid. From the degree of peak intensity shift, not only can the amount of change in the content of the test object be estimated, but also the test object can be identified.

[0039] Furthermore, in the liquid material of the present invention, the difference in solubility parameter ΔSP between the non-reactive additive (fluorescent marker compound) and the test object is preferably within the range of 6 to 22, more preferably within the range of 14 to 22. Having the solubility parameter difference ΔSP within this range facilitates interaction between the non-reactive additive and the test object, making it easy to obtain the peak intensity shift degree. Furthermore, transparency of products using the liquid material is easily achieved. The reason for setting ΔSP at 6 or greater is to prevent the fluorescent marker compound and the test object from associating without structural change, which would prevent the peak intensity shift degree corresponding to the amount of test object mixed in from being accurately obtained.

[0040] The solubility parameter is an index for evaluating the physical properties of a substance, particularly the dissolution behavior of a solvent, and Hildebrand's SP value (solubility parameter; δ) has conventionally been used. The "SP value" is a physical property value specific to a substance, which is expressed as the square root of the cohesive energy density of the substance. Furthermore, this SP value is expressed as follows using the Hansen solubility parameter (HSP value), which was proposed by Hansen as a parameter that takes into account the polarity of a substance by dividing it into three components: a dispersion force term (δD), a polar term (δP), and a hydrogen bond term (δH): SP value = (δD ２ +δP ２ +δH ２ ) ０．５

[0041] Hansen Solubility Parameters (HSP values) are based on the idea that "two substances with similar intermolecular interactions tend to dissolve easily in each other," and are composed of the following three parameters, which can be considered as coordinates in three-dimensional space (also called "Hansen space"). The closer the distance between the coordinates of two substances, the higher the affinity between them and the easier it is to dissolve them. δD: Energy due to intermolecular dispersion forces δP: Energy due to intermolecular dipole interactions δH: Energy due to intermolecular hydrogen bonds

[0042] The method for calculating δD, δP, and δH in the Hansen solubility parameters is not particularly limited, and the calculations may be performed by inputting the chemical structure into software, or may be performed experimentally. However, it is preferable to perform the calculations by inputting the chemical structure into software.

[0043] The HSP values ​​can be registered values ​​or estimated values ​​in commercially available software, HSPiP 5th Edition 5.0.10.1. This software can be obtained from sites such as https: / / www.hansen-solubility.com / . The method for estimating HSP using such software is based on, for example, the literature by C. M. Hansen et al., "Hansen Solubility Parameters: A User's Handbook, Second Edition" (CRC Press, 2007).

[0044] The SP value of the fluorescent marker compound contained in the liquid material of the present invention is preferably within a range of 5 to 10, the SP value of the resin is preferably within a range of 10 to 20, the SP value of the solvent is preferably within a range of 10 to 20, and the SP value of the test object is preferably within a range of 9 to 30. Furthermore, the difference in solubility parameters ΔSP between the solvent and the resin is preferably within a range of 6 to 22.

[0045] <Fluorescence Spectrum Observation Step> The fluorescence spectrum observation step is a step of acquiring a fluorescence spectrum of the liquid at an arbitrary excitation wavelength. The "arbitrary excitation wavelength" refers to acquiring a fluorescence fingerprint of the liquid or fluorescence spectra obtained by changing the excitation wavelength in increments of several nanometers, and selecting an excitation wavelength that exhibits a fluorescence spectrum effective for measurement from the acquired fluorescence spectra as the arbitrary excitation wavelength. It is particularly preferable to select an excitation wavelength with a high intensity from the acquired fluorescence spectra as the arbitrary excitation wavelength. However, the excitation wavelength is not limited to an excitation wavelength that exhibits a high-intensity fluorescence spectrum, and a wavelength absorbed by the test object may also be used as the excitation wavelength. Such an excitation wavelength is preferably within the range of 200 to 900 nm, and more preferably within the ranges of 200 to 400 nm and 680 to 900 nm.

[0046] The means for irradiating a liquid with light of an arbitrary excitation wavelength to acquire a fluorescence spectrum preferably includes an irradiation unit that irradiates the liquid with light of the excitation wavelength and a light receiving unit that receives fluorescence from the liquid excited by the light of the excitation wavelength. Details of the irradiation unit and the light receiving unit will be described later in the description of the liquid evaluation device.

[0047] Specifically, in the fluorescence spectrum observation step, the light irradiation unit irradiates the liquid with light of an arbitrary excitation wavelength, and the light receiving unit receives the fluorescence from the liquid excited by the irradiation. Note that in the fluorescence spectrum observation step, a plurality of excitation wavelengths may be used to obtain the respective fluorescence spectra.

[0048] <Spectral Analysis Step> The spectral analysis step is a step of acquiring data on the degree of peak intensity shift from the fluorescence spectrum acquired in the fluorescence spectrum observation step based on the interaction between the fluorescent marker compound in the liquid and the test object. Examples of "data on the degree of peak intensity shift" include data on the fluorescence intensity of the fluctuated peak and the amount of change in that fluorescence intensity, and data on the fluorescence wavelength of the fluctuated peak and the amount of change in that fluorescence wavelength. Furthermore, the spectral analysis step may simply acquire the data, or may include analyzing and processing the acquired data. Examples of means for acquiring the data on the degree of peak intensity shift include a general-purpose personal computer.

[0049] <Data Processing Step> The data processing step includes a step of calculating the content of the test object using a calibration curve prepared in advance, based on at least the peak intensities included in the data on the degree of peak intensity shift acquired in the spectrum analysis step. The calibration curve is prepared based on the acquired data by using a liquid material containing a known content of the test object and a fluorescent marker compound, irradiating the liquid material with light of an arbitrary excitation wavelength, and obtaining data on fluorescence intensity and fluorescence wavelength from the fluorescence spectrum of the liquid material excited by the irradiation. For example, the vertical axis of the calibration curve represents the fluorescence peak intensity, and the horizontal axis represents the content of the test object. An example of a means for calculating the content of the test object is a general personal computer.

[0050] After the data processing step, it is preferable to display data such as the calculated content of the test object, the excitation wavelength of the irradiated light, the fluorescence wavelength and fluorescence intensity of the liquid material, etc. on the information display unit.

[0051] [Configuration of the Liquid Material Evaluation Device] The liquid material evaluation device (hereinafter also referred to simply as the "evaluation device") of the present invention can be applied to manufacturing processes using various types of liquid materials depending on the purpose. It continuously measures the fluorescence spectrum of the liquid material in-line to determine the amount of fluctuation in the content of a test object in the liquid material and identify the test object to evaluate the liquid material. The evaluation device of the present invention is an evaluation device for a liquid material containing at least a solvent, a resin, and a non-reactive additive, where the non-reactive additive is a fluorescent marker compound. The evaluation device includes a fluorescence spectrum observation unit that acquires the fluorescence spectrum of the liquid material at an arbitrary excitation wavelength, and a spectrum analysis unit that acquires data on the degree of peak intensity shift from the acquired fluorescence spectrum based on the interaction between the fluorescent marker compound in the liquid material and the test object. The evaluation device also preferably includes a data processing unit that calculates the content of the test object using a calibration curve based on the peak intensity included in the data on the degree of peak intensity shift, and an information display unit that displays the data on the degree of peak intensity shift.

[0052] Fig. 1 is a diagram showing a schematic configuration example of a liquid material evaluation device of the present invention. As shown in Fig. 1, the evaluation device 100 is installed inline in a manufacturing process using a liquid material, and includes a fluorescence spectrum observation unit 110 and a computer 120 having a spectrum analysis unit, a data processing unit, and an information display unit.

[0053] <Fluorescence spectrum observation section> The fluorescence spectrum observation section 110 preferably has a configuration including an irradiation unit 111 that irradiates the liquid material with light of an arbitrary excitation wavelength, and a light receiving unit 112 that receives fluorescence from the liquid material excited by the light of the excitation wavelength and measures the fluorescence spectrum.

[0054] The irradiation unit 111 irradiates the liquid with light of a given excitation wavelength, causing the fluorescent marker compound to emit fluorescence. The irradiation unit 111 is preferably composed of, for example, an LED driver 111a, an LED light source 111b, and an irradiation fiber collimator 111c. The LED driver 111a supplies a current to turn on the LED light source 111b, causing the liquid to be irradiated with light of a given excitation wavelength from the LED light source 111b via the irradiation fiber collimator 111c. Commercially available irradiation units can be used, such as high-power LED light sources (Ocean Photonics, LSM series) and high-power UV-Vis fiber light source units (Hamamatsu Photonics, L10290).

[0055] The range of excitation light wavelengths is preferably within the visible light range. Here, the wavelength of the excitation light irradiated from the irradiation unit can be arbitrarily changed by the user using a keyboard, mouse, etc. to input multiple excitation wavelengths that show fluorescence spectra effective for measurement. It is preferable that the multiple excitation wavelengths that show fluorescence spectra effective for measurement be selected from the fluorescence fingerprint of the liquid or fluorescence spectra obtained by changing the excitation wavelength in increments of several nanometers, which are obtained in advance.

[0056] The light-receiving unit 112 receives fluorescence emitted from the fluorescent marker compound when irradiated with excitation light, measures the excitation light wavelength, fluorescence wavelength, and fluorescence intensity from the received fluorescence, and transmits the measured data to a spectrum analysis unit (computer 120). The light-receiving unit 112 is preferably composed of, for example, a spectroscope 112a and a light-receiving fiber collimator 112b. The fluorescence wavelength and fluorescence intensity of the fluorescence received by the spectroscope 112a are measured via the light-receiving fiber collimator 112b, and the data is transmitted to the spectrum analysis unit (computer 120). A commercially available product can be used as the spectroscope, and examples thereof include a compact fiber optic spectroscope (USB2000, manufactured by Ocean Photonics) and a multichannel spectroscope (PMA-12, manufactured by Hamamatsu Photonics KK).

[0057] The irradiation fiber collimator 111c connected to the LED light source 111b is arranged near the pipe (for example, symbol P1 in FIG. 1 ) through which the liquid flows or the liquid feed pump P2 so that light can be irradiated onto the liquid. The light-receiving fiber collimator 112b connected to the spectroscope 112a is also arranged near the pipe P1 through which the liquid flows or the liquid feed pump P2 so that fluorescence from the liquid can be received. The irradiation fiber collimator 111c and the light-receiving fiber collimator 112b are preferably covered with a light-shielding cover 113.

[0058] The spectrum analysis unit acquires data on the degree of peak intensity shift from the fluorescence spectrum acquired by the spectrum observation unit based on the interaction between the fluorescent marker compound in the liquid and the test object, and transmits the acquired data on the degree of peak intensity shift to the data processing unit.

[0059] The data processing unit calculates the content of the test object from the data on the peak intensity shift degree acquired by the spectrum analysis unit using a calibration curve created in advance. The calculated data on the content and peak intensity shift degree are sent to the information display unit.

[0060] <Information Display Unit> The information display unit performs display according to instructions of a display signal input from the data processing unit, and specifically displays data related to the peak intensity shift degree and the content of the test object. Specific examples of data related to the peak intensity shift degree include the excitation wavelength of the light irradiated onto the liquid material, the fluorescence spectrum at that excitation wavelength, and the peak intensity shift degree (the fluorescence wavelength of the characteristic peak and the amount of change in fluorescence intensity). The information display unit is configured, for example, with an LCD (Liquid Crystal Display) or the like, and displays information using, for example, a dot matrix method.

[0061] The spectrum analysis unit, data processing unit, and information display unit may be, for example, a general computer (personal computer) 120. When handling extremely large amounts of data or for applications requiring ultra-high speed processing, a dedicated integrated circuit (ASIC) may be provided. The computer 120 controls the overall operation of the evaluation device 100 and includes a memory, a control unit, a calculation processing unit, and the like. The user can input measurement processing conditions and the like into the computer 120 using a keyboard and mouse.

[0062] Next, an example of a process for acquiring data on the degree of peak intensity shift of a liquid material in the liquid material evaluation device 100 configured as described above will be described with reference to Fig. 2. Fig. 2 is a flowchart showing a control procedure executed by the computer 120 in the liquid material evaluation device. As shown in Fig. 2, a spectrophotometer is used to measure a fluorescent marker compound in the liquid material to be measured in advance, and from a group of fluorescence spectra measured by changing the fluorescence fingerprint or excitation wavelength in increments of several nanometers (for example, 5 nm), the LED light source is switched to irradiate an excitation wavelength effective for measurement selected by the user (step S1).

[0063] Next, the liquid is irradiated with excitation light from the switched LED light source (irradiation unit) (step S2). The irradiation time and irradiation intensity of the excitation light are appropriately set according to the fluorescent marker compound in the liquid. The liquid may be transported by a transport mechanism so that it is irradiated at a desired position. When the liquid is a dope or a coating liquid, it is preferably irradiated inline with a film-forming device.

[0064] Next, excitation light is irradiated onto the liquid, and the fluorescence from the fluorescent marker compound in the liquid excited by the light of the excitation wavelength is received as a spectrometer (light-receiving unit), i.e., the fluorescence spectrum is observed (step S3). Based on the fluorescence spectrum, the peak wavelength and intensity are measured, i.e., data on the degree of peak intensity shift is acquired (spectral analysis) (step S4), and the acquired data is transmitted to a computer. From the data on the degree of peak intensity shift transmitted to the computer, the content of the test object is calculated based on a previously prepared calibration curve, i.e., data processing is performed (step S5). It is determined whether the calculated content of the test object is within a specified value range (step S6). If it is within the range (step S6; YES), it is determined that there is no abnormality, and the process ends. If it is outside the range (step S6; NO), it is determined that there is an abnormality, and a warning is issued by display or voice (step S7). An abnormality record is kept (step S8), including the location, time, and type of abnormality, and the process ends.

[0065] <Application Examples of the Liquid Material Evaluation Device> (Application Example 1) A case where the liquid material evaluation device of the present invention is applied to the film formation process of an optical film will be described. The optical film can be formed by a solution casting film-forming method or a melt casting film-forming method. The following description will be given using the solution casting film-forming method as an example. FIG. 3 is a schematic diagram showing an example of the dope preparation process, casting process, drying process, and winding process of the solution casting film-forming method. A microparticle dispersion in which a solvent and a matting agent are dispersed by a disperser passes from a feed kettle 41 through a filter 44 and is stored in a stock kettle 42. Meanwhile, a cycloolefin resin, which is the main dope, is dissolved in a dissolving kettle 1 together with a solvent and a fluorescent marker compound according to the present invention. A matting agent stored in a stock kettle 42 is added and mixed to form a main dope. The obtained main dope is filtered by a filter 3, a stock kettle 4, and a filter 6. An additive is added through a confluence pipe 20. The mixture is mixed in a mixer 21 and sent to a pressure die 30.

[0066] On the other hand, additives (e.g., ultraviolet absorbers) are dissolved in a solvent, passed through a filter 12 from an additive supply tank 10, and stored in a stock tank 13. Then, the additives are passed through a filter 15, a conduit 16, a junction pipe 20, and a mixer 21 to be mixed with the main dope.

[0067] The main dope fed to the pressure die 30 is cast onto a metal belt-like support 31 to form a web 32, which is dried to a predetermined extent and then peeled off at a peeling position 33 to obtain a raw film. The peeled web 32 is dried while passing through multiple conveying rollers until a predetermined residual solvent content is reached, and then stretched in the longitudinal direction or width direction by a stretching device 34 to a predetermined stretch ratio and heated to a predetermined residual solvent content. After stretching, the web is dried while passing through a drying device 35 by conveying rollers 36 until a predetermined residual solvent content is reached, and then wound up into a roll by a winding device 37.

[0068] In the solution casting film-forming method as described above, the liquid material evaluation device of the present invention is preferably disposed as follows depending on the purpose of detecting the identity of the liquid material: (1) When the purpose is to detect the state of the dope before filtration, it is preferably disposed between the liquid feed pump 2 and the filter 3. (2) When the purpose is to detect the state of the dope before the junction pipe 20, it is preferably disposed between the filter 6 and the conduit 8 or between the filter 15 and the conduit 16. (3) When the purpose is to detect the state of the dope after junction, it is preferably disposed between the mixer 21 and the pressure die 30. By disposing the liquid material evaluation device of the present invention in this manner during the process of the solution casting film-forming method, for example, the fluorescence spectrum of the dope (liquid material) can be measured at any time, and any slight fluctuation in the water content or impurities in the dope can be easily and quickly detected.

[0069] The dope used in the solution casting film-forming method may contain at least a solvent, a resin, and a non-reactive additive (fluorescent marker compound). The resin used in the dope according to the present invention is preferably a cycloolefin resin, an acrylic resin, a triacetyl cellulose resin, or the like. The cycloolefin resin will be described below.

[0070] <Cycloolefin Resin> The cycloolefin resin contained in the dope according to the present invention is preferably formed from a resin composition containing at least one hydrogen bond accepting group. Generally, cycloolefin resins are hydrophobic resins, and therefore, when formed into a film, they tend to separate in the presence of moisture, which is undesirable from the viewpoint of transparency. However, when formed from a resin composition containing at least one hydrogen bond accepting group, they can form hydrogen bonds with the hydroxyl groups of alcohols or hindered phenol compounds, thereby maintaining transparency even in a state containing a certain amount of moisture, and conversely, the hydrogen bonds improve film strength. The "hydrogen bond accepting group" refers to a functional group that accepts a hydrogen atom when forming a hydrogen bond.

[0071] Examples of hydrogen bond accepting groups include alkoxy groups having 1 to 10 carbon atoms, acyloxy groups having 1 to 10 carbon atoms, alkoxycarbonyl groups having 2 to 10 carbon atoms, allyloxycarbonyl groups, cyano groups, amide groups, imide ring-containing groups, triorganosiloxy groups, triorganosilyl groups, acyl groups, alkoxysilyl groups having 1 to 10 carbon atoms, sulfonyl-containing groups, and carboxy groups. To explain these polar groups more specifically, the alkoxy groups include, for example, a methoxy group and an ethoxy group; the acyloxy groups include, for example, alkylcarbonyloxy groups such as an acetoxy group and a propionyloxy group, and arylcarbonyloxy groups such as a benzoyloxy group; the alkoxycarbonyl groups include, for example, a methoxycarbonyl group and an ethoxycarbonyl group; the allyloxycarbonyl groups include, for example, a phenoxycarbonyl group, a naphthyloxycarbonyl group, a fluorenyloxycarbonyl group, a biphenylyloxycarbonyl group; the triorganosiloxy groups include, for example, a trimethylsiloxy group and a triethylsiloxy group; the triorganosilyl groups include, for example, a trimethylsilyl group and a triethylsilyl group; and the alkoxysilyl groups include, for example, a trimethoxysilyl group and a triethoxysilyl group.

[0072] The amount of the cycloolefin resin containing the hydrogen bond-accepting group contained in the resin component is not particularly limited, but is preferably 10 to 100% by mass. A content of 10% by mass or more is preferred because the resulting ring-opened copolymer is more likely to exhibit solubility in solvents such as toluene and dichloromethane, and from the viewpoints of solubility, film strength, and transparency, a content of 30 to 100% by mass is even more preferred.

[0073] Examples of the cycloolefin resin according to the present invention include the following (co)polymers.

[0074]

[0075] [In the formula, p is 0 or 1, and m is an integer of 0 or 1 or more. １ ~R ４ each independently represents a hydrogen atom, a hydrocarbon group, a halogen atom, or a hydrogen bond accepting group. １ ~R ４ may be bonded to each other to form an unsaturated bond, a monocyclic ring, or a polycyclic ring, and the monocyclic ring or polycyclic ring may have a double bond or form an aromatic ring.] In the present invention, the preferred ratio of hydrogen bond accepting groups contained in the cycloolefin resin is １ ~R ４ It is preferred that one or two of these have a hydrogen bond accepting group.

[0076] The ratio of hydrogen bond accepting groups in a cycloolefin resin can be determined by, for example, carbon-13 nuclear magnetic resonance ( １３ The compound can be identified using 1C NMR spectroscopy.

[0077] In addition, in the general formula (I), R １ and R ３ is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 2 carbon atoms; R ２ and R ４ At least one of the groups represents a hydrogen bond accepting group having polarity other than a hydrogen atom or a hydrocarbon group, and p and m are preferably m=1 and p=0 from the viewpoint of a high glass transition temperature and excellent mechanical strength.

[0078] Examples of halogen atoms include fluorine atoms, chlorine atoms, and bromine atoms. Examples of hydrocarbon groups having 1 to 30 carbon atoms include alkyl groups such as methyl groups, ethyl groups, and propyl groups; cycloalkyl groups such as cyclopentyl groups and cyclohexyl groups; alkenyl groups such as vinyl groups, allyl groups, and propenyl groups; and aromatic groups such as phenyl groups, biphenyl groups, naphthyl groups, and anthracenyl groups. These hydrocarbon groups may be substituted, and examples of the substituent include halogen atoms such as fluorine atoms, chlorine atoms, and bromine atoms, and phenylsulfonyl groups.

[0079] The preferred molecular weight of the cycloolefin resin according to the present invention is 0.2 to 5 cm in terms of intrinsic viscosity [η]inh. ３ / g, more preferably 0.3 to 3 cm ３ / g, particularly preferably 0.4 to 1.5 cm ３ / g, and the number average molecular weight (Mn) in terms of polystyrene measured by gel permeation chromatography (GPC) is 8,000 to 100,000, more preferably 10,000 to 80,000, and particularly preferably 12,000 to 50,000, and the weight average molecular weight (Mw) is preferably in the range of 20,000 to 300,000, more preferably 30,000 to 250,000, and particularly preferably 40,000 to 200,000.

[0080] When the intrinsic viscosity [η]inh, number average molecular weight, and weight average molecular weight are within the above ranges, the cycloolefin resin has good heat resistance, water resistance, chemical resistance, and mechanical properties, and the moldability of the cycloolefin resin film according to the present invention is good.

[0081] The glass transition temperature (Tg) of the cycloolefin resin according to the present invention is usually 110°C or higher, preferably 110 to 350°C, more preferably 120 to 250°C, and particularly preferably 120 to 220°C. A Tg of 110°C or higher is preferred because deformation during use under high temperature conditions or secondary processing such as coating or printing is suppressed. A Tg of 350°C or lower is preferred because resin deterioration due to molding or heat during molding is suppressed.

[0082] As the cycloolefin resin described above, commercially available products can be preferably used. Examples of commercially available products include those sold by JSR Corporation under the trade names Arton G, Arton F, Arton R, and Arton RX, and these can be used.

[0083] <<Solvent>> Examples of the solvent contained in the dope according to the present invention include organic solvents. Examples of the organic solvent include chlorine-based solvents such as chloroform and dichloromethane; aromatic solvents such as toluene, xylene, benzene, and mixtures thereof; alcohol-based solvents such as methanol, ethanol, isopropanol, n-butanol, and 2-butanol; methyl cellosolve, ethyl cellosolve, butyl cellosolve, dimethylformamide, dimethyl sulfoxide, dioxane, cyclohexanone, tetrahydrofuran, acetone, methyl ethyl ketone (MEK), ethyl acetate, and diethyl ether. These solvents may be used alone or in combination.

[0084] The organic solvent is preferably a mixed solvent of a good solvent and a poor solvent, and examples of the good solvent include dichloromethane as a chlorine-based organic solvent and methyl acetate, ethyl acetate, amyl acetate, acetone, methyl ethyl ketone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-hexafluoro-1-propanol, 1, Examples of the good solvent include 3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2,3,3,3-pentafluoro-1-propanol, nitroethane, methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, and tert-butanol, with dichloromethane being preferred. The good solvent is preferably used in an amount of 55% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more, based on the total amount of the solvent.

[0085] The poor solvent is preferably an alcohol-based solvent, and the alcohol-based solvent is preferably selected from methanol, ethanol, and butanol, from the viewpoints of improving releasability and enabling high-speed casting. Among these, methanol or ethanol is preferably used. A high alcohol content in the dope causes the web to gel, facilitating peeling from the metal support. A low alcohol content also promotes dissolution of the cycloolefin resin and other compounds in a non-chlorine-based organic solvent. In the present invention, in order to improve the flatness of the resulting optical film, it is preferable to form the film using a dope having an alcohol concentration in the range of 0.5 to 15.0% by mass.

[0086] <Non-reactive additives> Examples of the non-reactive additives (fluorescent marker compounds) contained in the dope according to the present invention include the above-mentioned antioxidants (e.g., Irganox 1076 (manufactured by BASF Japan)) and dyes (NIR dyes, NUV dyes), etc.

[0087] Other Additives The dope according to the present invention may further contain a plasticizer, a retardation increasing agent, or a matting agent such as silica particles, as described in JP-A-2017-90872.

[0088] (Application Example 2) Next, a case where the liquid material evaluation device of the present invention is applied to a process of applying a coating liquid for a hard coat layer to a functional film will be described. FIG. 4 is a schematic diagram showing an example of a hard coat layer forming device used when manufacturing a functional film. The hard coat layer forming device is a so-called roll-to-roll type device. The hard coat layer forming device 130 includes a delivery roller 132a, transport rollers 133a, 133b, 133c, 133d, and 133e, a hard coat layer forming coating liquid applying device 134, a heat drying section 135, a transport roller 136, an ultraviolet irradiation device 137, and a take-up roller 132b.

[0089] In this hard coat layer forming apparatus 130, a film 131 having a substrate and a functional layer is fed from a feed roller 132a. Then, a coating liquid for forming a hard coat layer is applied onto the functional layer or substrate of the film 131 after being fed from the roller by a coating liquid applicator 134. It is preferable to neutralize the film before applying the coating liquid for forming a hard coat layer. Examples of the coating liquid applicator include a die coater, a gravure coater, and a comma coater.

[0090] The substrate coated with the hard coat layer-forming coating liquid is transported to the heat drying section 135 via transport rollers 133b and 133c. In the drying section, the solvent in the coating liquid is dried. The drying means is not particularly limited, and hot air drying, infrared drying, or microwave drying may be used. Note that, although four drying devices are shown in FIG. 4 in the heat drying section 135, the drying is not limited to a form in which multiple drying devices are used, and drying may be performed using only one drying device. The drying temperature in this case is appropriately set to a temperature at which the solvent used can be removed, and is usually 70 to 120°C.

[0091] The substrate coated with the hard coat layer-forming coating liquid is transported via transport rollers 133d for ultraviolet irradiation by an ultraviolet irradiation device 137. In the ultraviolet irradiation device 137, the ultraviolet curable resin is cured by the irradiated ultraviolet light. As the ultraviolet irradiation device, for example, an ultraviolet lamp such as a high-pressure UV lamp (high-pressure mercury lamp) or a metal halide lamp can be used. Although a ultraviolet irradiation device is illustrated in FIG. 4, other curing devices such as a heating device can be used depending on the curable resin used. In the case of a polysiloxane-based hard coat material, after application and drying of the solvent, it is preferable to perform heat treatment for 30 minutes to several days at a temperature range of 50 to 150°C to promote curing and crosslinking of the hard coat material.

[0092] When using an active energy ray curable resin, the reactivity changes depending on the irradiation wavelength, illuminance, and light amount of the active energy ray, so it is necessary to select the optimum conditions depending on the resin to be used. For example, when using an ultraviolet lamp as the active energy ray, the illuminance should be 50 to 1500 mW / cm.２ The irradiation energy amount is preferably 50 to 1500 mJ / cm ２ is preferred.

[0093] By the ultraviolet irradiation treatment, a hard coat layer is formed on the substrate or the functional layer. The thickness of the formed hard coat layer is preferably 0.1 to 20 μm, more preferably 1 to 15 μm, and even more preferably 3 to 10 μm. If the thickness is 0.1 μm or more, the hard coat properties tend to be improved, and if the thickness is 20 μm or less, the hard coat layer tends to curl less and maintain its flex resistance.

[0094] Although the above describes a form in which the hard coat layer is formed on the substrate or the functional layer, the present invention is not limited to this form, and the hard coat layer may be formed on other intermediate layers or the like.

[0095] In the hard coat layer forming apparatus as described above, the liquid material evaluation device of the present invention is preferably disposed, for example, in the coating liquid application device 134, near the transport roller 133b immediately after the hard coat layer forming coating liquid is applied, between the transport rollers 133c and 133d during drying in the drying section, or near the transport roller 133d immediately after drying. By disposing the liquid material evaluation device of the present invention in this manner during the hard coat layer forming process, for example, the fluorescence spectrum of the hard coat layer forming coating liquid or the applied hard coat layer coating film can be measured at any time, and any slight fluctuations in the water content or impurities in the hard coat layer forming coating liquid or the coating film can be easily and quickly detected.

[0096] The coating liquid for forming a hard coat layer used in the hard coat layer forming step may contain at least a solvent, a resin, and a non-reactive additive (a fluorescent marker compound).

[0097] Resin Examples of resins used in the coating liquid for forming a hard coat layer according to the present invention include thermosetting resins and active energy ray curable resins. Active energy ray curable resins are preferred because they are easy to mold. Such curable resins can be used alone or in combination of two or more. Furthermore, commercially available products or synthetic products can be used as the curable resin.

[0098] The active energy ray curable resin refers to a resin that cures through a crosslinking reaction or the like when irradiated with active energy rays such as ultraviolet rays or electron beams. A component containing a monomer having an ethylenically unsaturated double bond is preferably used as the active energy ray curable resin, and the active energy ray hard coat layer is formed by curing the resin when irradiated with active energy rays such as ultraviolet rays or electron beams. Representative examples of the active energy ray curable resin include ultraviolet curable resins and electron beam curable resins, with ultraviolet curable resins that cure when irradiated with ultraviolet rays being preferred. The active energy ray curable resin may be used alone or in combination of two or more.

[0099] Preferred examples of ultraviolet-curable resins include ultraviolet-curable urethane acrylate resins, ultraviolet-curable polyester acrylate resins, ultraviolet-curable epoxy acrylate resins, ultraviolet-curable polyol acrylate resins, and ultraviolet-curable epoxy resins. Of these, ultraviolet-curable urethane acrylate resins and ultraviolet-curable polyol acrylate resins are preferred.

[0100] UV-curable urethane acrylate resins can generally be easily obtained by reacting a polyester polyol with an isocyanate monomer or prepolymer, followed by further reaction with a hydroxyl-containing acrylate monomer such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate (hereinafter, "acrylate" refers to acrylate only, as methacrylate is included), or 2-hydroxypropyl acrylate. For example, a mixture of 100 parts of Unidic 17-806 (manufactured by Dai Nippon Ink Co., Ltd.) and 1 part of Coronate L (manufactured by Nippon Polyurethane Co., Ltd.), as described in JP-A-59-151110, is preferably used. Commercially available UV-curable urethane acrylate resins may also be used, including Beamset (registered trademark) 575 and 577 (manufactured by Arakawa Chemical Industries, Ltd.) and the Shiko (registered trademark) UV series.

[0101] Examples of ultraviolet-curable polyester acrylate resins include those generally formed by reacting polyester polyol with 2-hydroxyethyl acrylate or 2-hydroxyacrylate monomers, and those described in JP-A-59-151112 can be used.

[0102] Examples of ultraviolet-curable epoxy acrylate resins include those produced by oligomerizing epoxy acrylate, adding a reactive diluent and a photopolymerization initiator to the oligomer, and allowing the mixture to react. The resins described in JP-A-1-105738 can be used.

[0103] Examples of the ultraviolet-curable polyol acrylate resin include ethylene glycol (meth)acrylate, polyethylene glycol di(meth)acrylate, glycerin tri(meth)acrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaacrylate, etc. As the ultraviolet-curable polyol acrylate resin, commercially available products may be used, and examples of commercially available products include Sartomer SR295 and SR399 (manufactured by Sartomer Corporation).

[0104] Furthermore, a polymerizable silicone compound may be used in combination with (or alone than) an ultraviolet-curable resin, and it is preferable to use the polymerizable silicone compound in combination with the ultraviolet-curable resin.

[0105] The polymerizable silicone compound is a compound having a main skeleton (silicone skeleton) formed by siloxane bonds and a polymerizable group within the molecule.

[0106] The polymerizable group is a group polymerizable with the ultraviolet-curable resin, and examples thereof include groups having a polymerizable double bond, such as a (meth)acryloyl group or a (meth)acryloyloxy group. A (meth)acryloyl group is preferred. Therefore, a preferred polymerizable silicone compound is preferably a silicone (meth)acrylate or a silicone (meth)acrylate oligomer (hereinafter collectively referred to as silicone (meth)acrylate).

[0107] In addition, from the viewpoint of improving compatibility with the above-mentioned ultraviolet-curable resin, the polymerizable silicone compound is preferably an organically modified polymerizable silicone compound containing a moiety in the molecule that improves compatibility with the ultraviolet-curable resin. Examples of such organically modified polymerizable silicone compounds include urethane-modified, amino-modified, alkyl-modified, epoxy-modified, carboxyl-modified, alcohol-modified, fluorine-modified, alkylaralkyl polyether-modified, epoxy-polyether-modified, and polyether-modified polymerizable silicone compounds.

[0108] For example, when the ultraviolet-curable resin contains an ultraviolet-curable urethane acrylate resin, the polymerizable silicone compound is preferably a urethane-modified silicone (meth)acrylate. The urethane-modified silicone (meth)acrylate can be obtained, for example, by reacting a silicone compound having OH groups at both ends with a polyvalent isocyanate to obtain an isocyanate-terminated silicone compound, and then reacting the isocyanate-terminated silicone compound with the hydroxyl group-containing (meth)acrylate.

[0109] Commercially available polymerizable silicone compounds can be used, and examples of commercially available products include EBECRYL1360, EBECRYL350, and KRM8495 (manufactured by Daicel Allnex Co., Ltd.), CN9800, and CN990 (manufactured by Arkema).

[0110] The polymerizable silicone compound also forms a polymer, and therefore becomes a polymerizable component of the resin.

[0111] For the ultraviolet-curable resin, a photopolymerization initiator (radical polymerization initiator) is preferably used. Examples of photopolymerization initiators that can be used include benzoin and its alkyl ethers, such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzyl methyl ketal; acetophenones, such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 1-hydroxycyclohexyl phenyl ketone; anthraquinones, such as methylanthraquinone, 2-ethylanthraquinone, and 2-amylanthraquinone; thioxanthones, such as thioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone; ketals, such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones, such as 4,4-bismethylaminobenzophenone, and azo compounds. These can be used alone or in combination of two or more. In addition, it can be used in combination with a photoinitiator aid such as a tertiary amine such as triethanolamine or methyldiethanolamine; or a benzoic acid derivative such as 2-dimethylaminoethylbenzoic acid or ethyl 4-dimethylaminobenzoate. Commercially available photopolymerization initiators may be used, such as Irgacure (registered trademark) -184, 819, 907, 651, 1700, 1800, 819, 369, 261, DAROCUR-TPO (manufactured by BASF Japan Ltd.), Darocure (registered trademark) -1173 (manufactured by Merck Ltd.), Ezacure-KIP150, TZT (manufactured by DKSH Japan Ltd.), Kayacure (registered trademark) BMS, and DMBI (manufactured by Nippon Kayaku Co., Ltd.). The amount of these photopolymerization initiators used is preferably 0.5 to 30 parts by weight, more preferably 1 to 25 parts by weight, per 100 parts by weight of the polymerizable component of the resin.

[0112] The thermosetting resin may be a polysiloxane-based hard coat.

[0113] The starting material for polysiloxane hard coats is represented by the general formula RmSi(OR')n. R and R' represent alkyl groups having 1 to 10 carbon atoms, and m and n are integers that satisfy the relationship m + n = 4. A starting material in which hydrolyzable groups such as methoxy and ethoxy groups have been replaced with hydroxyl groups is generally referred to as a polyorganosiloxane hard coat. By applying this and curing it with heat, a dehydration condensation reaction is promoted, resulting in curing and crosslinking, forming a hard coat film.

[0114] As the polyorganosiloxane-based hard coat, commercially available products can be used, such as Surcoat series (manufactured by Doken), SR2441 (Toray Dow Corning Co., Ltd.), KF-86 (Shin-Etsu Silicone Co., Ltd.), Perma-New (registered trademark) 6000 (California Hardcoating Company).

[0115] In the case of a polysiloxane-based hard coat, after application and drying of the solvent, heat treatment is required for 30 minutes to several days at a temperature of 50°C or higher and 150°C or lower to promote curing and crosslinking of the hard coat. Taking into consideration the heat resistance of the coated substrate and the stability of the substrate when rolled, treatment at 40°C or higher and 80°C or lower for 2 days or longer is preferred.

[0116] The blending amount of the curable resin (including the polymerizable silicone compound) in the coating liquid for forming the hard coat layer is preferably 40 to 90 mass %, and more preferably 50 to 85 mass %, relative to 100 mass % (solid content) of the total hard coat layer.

[0117] <<Solvent>> The solvent contained in the coating liquid for forming a hard coat layer according to the present invention can be appropriately selected from hydrocarbons (toluene, xylene), alcohols (methanol, ethanol, isopropanol, butanol, cyclohexanol), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone), esters (methyl acetate, ethyl acetate, methyl lactate), glycol ethers, and other organic solvents, or these can be mixed and used. The amount of solvent in the coating liquid for forming a hard coat layer is appropriately set so as to be able to dissolve and disperse the curable resin, and is about 20 to 80% by mass relative to 100% by mass of the coating liquid.

[0118] <<Non-reactive additives>> Examples of the non-reactive additives (fluorescent marker compounds) contained in the coating liquid for forming a hard coat layer according to the present invention include the above-mentioned antioxidants (e.g., Irganox 1076 (manufactured by BASF Japan Ltd.)) and dyes (NIR dyes, NUV dyes), etc.

[0119] <<Other Additives>> The coating liquid for forming a hard coat layer preferably contains metal oxide particles described in JP 2018-196322 A for the purpose of imparting infrared shielding properties to the hard coat layer, improving mechanical strength, etc. Furthermore, a surfactant can be added to the coating liquid for forming a hard coat layer to impart leveling properties, water repellency, slip properties, etc. The type of surfactant is not particularly limited, and acrylic surfactants, silicone surfactants, fluorine-based surfactants, etc. can be used. In particular, from the viewpoint of leveling properties, water repellency, and slip properties, it is preferable to use a fluorine-based surfactant. Examples of fluorine-based surfactants that can be used include commercially available products such as the Megafac (registered trademark) F series (F-430, F-477, F-552 to F-559, F-561, F-562, etc.) manufactured by DIC Corporation, the Megafac (registered trademark) RS series (RS-76-E, etc.) manufactured by DIC Corporation, the Surflon (registered trademark) series manufactured by AGC Seimi Chemical Co., Ltd., the POLYFOX series manufactured by OMNOVA SOLUTIONS, the ZX series manufactured by T&K TOKA Corporation, the Optool series manufactured by Daikin Industries, Ltd., and the Futergent (registered trademark) series (602A, 650A, etc.) manufactured by Neos Corporation.

[0120] The method for producing the coating liquid for forming a hard coat layer is not particularly limited, and the coating liquid can be obtained by adding each component to a solvent and appropriately mixing them. The order and method of addition are not particularly limited, and each component may be added and mixed sequentially while stirring, or may be added and mixed all at once while stirring.

[0121] The substrate used in the hard coat layer forming step according to the present invention is not particularly limited, but is preferably a resin substrate from the viewpoint of flexibility, etc., and may be transparent or opaque. In applications such as automobile applications where transparency in visible light is required from the viewpoint of design, it is preferable that the substrate is transparent in the visible light region.

[0122] Examples of resin substrates that can be used include polyolefin films (polyethylene, polypropylene, etc.), polyester films (polyethylene terephthalate, polyethylene naphthalate, etc.), polyvinyl chloride, and cellulose triacetate, with polyester films being preferred. The polyester film (hereinafter referred to as "polyester") is not particularly limited, but is preferably a polyester having film-forming properties and consisting primarily of a dicarboxylic acid component and a diol component. Among polyesters, polyesters consisting primarily of terephthalic acid or 2,6-naphthalenedicarboxylic acid as the dicarboxylic acid component and ethylene glycol or 1,4-cyclohexanedimethanol as the diol component are preferred in terms of transparency, mechanical strength, dimensional stability, and the like. Among these, polyesters consisting primarily of polyethylene terephthalate or polyethylene naphthalate, copolymer polyesters consisting of terephthalic acid, 2,6-naphthalenedicarboxylic acid, and ethylene glycol, and polyesters consisting primarily of a mixture of two or more of these polyesters are preferred.

[0123] The thickness of the substrate is preferably 10 to 300 μm, more preferably 20 to 150 μm. The substrate may be a laminate of two or more layers, and in this case, the types of the layers may be the same or different.

[0124] The resin substrate can be produced by a conventionally known method. The resin substrate may be an unstretched film, a stretched film stretched in one direction, or a biaxially stretched film. A stretched film is preferred from the viewpoints of improving strength and suppressing thermal expansion.

[0125] The functional layer formed on the substrate may be any thin film that provides some function to the substrate, such as an optical film that transmits or reflects / absorbs specific light rays (e.g., an anti-reflection film, an infrared shielding film, an ultraviolet shielding film, etc.), a barrier film that suppresses the transmission of oxygen and / or water vapor, a polarizing film, a retardation film, or a photosensitive film.

[0126] Here, a film having a substrate and a functional layer is sufficient as long as it has a substrate and a functional layer, and includes not only a form in which the functional layer is provided directly on the substrate, but also a form in which another intermediate layer is provided on the substrate and the functional layer is provided on the intermediate layer, a form in which another intermediate layer is provided on the side of the substrate opposite the functional layer, and a form in which another intermediate layer is included on the functional layer.

[0127] The material constituting the functional layer is appropriately selected depending on the intended functional layer. Examples thereof include metal oxides such as aluminum, silica, zirconia, tantalum oxide, titanium oxide, tin oxide, and tin-doped indium oxide, metal oxynitrides such as silicon oxynitride, metals such as silver, gold, and copper, metal fluorides such as magnesium fluoride, polymers, and conductive polymers such as polythiophene. The functional layer preferably contains a polymer because it has low conductivity and the effects of the present invention can be more easily achieved.

[0128] The functional layer may contain various additives as needed, specifically, various known additives such as various anionic, cationic, or nonionic surfactants, dispersants such as polycarboxylic acid ammonium salts, allyl ether copolymers, benzenesulfonic acid sodium salts, graft compound-based dispersants, and polyethylene glycol-based nonionic dispersants, pH adjusters, and antifoaming agents.

[0129] The thickness of the functional layer is appropriately set so as to satisfy the required function, and is, for example, about 10 nm to 100 μm.

[0130] (Application Example 3) The liquid material evaluation device of the present invention can also be applied during the process of applying a coating liquid for forming an antistatic layer to be provided on a near-infrared reflective film. In this case, the coating liquid for the antistatic layer can be applied using a coating liquid application device (such as a gravure coater) in the same manner as in the above-mentioned Application Example 2. Specifically, in the device for forming the antistatic layer, the liquid material evaluation device of the present invention is preferably disposed, for example, in the coating liquid application device or near the transport roller immediately after the coating of the coating liquid for forming the antistatic layer, or near the transport roller during drying by a drying section after coating or immediately after drying.

[0131] By disposing the liquid material evaluation device of the present invention during the antistatic layer formation process in this manner, it is possible to measure, for example, the fluorescence spectrum of the coating liquid for forming an antistatic layer or the coating film of the applied antistatic layer at any time, and any slight fluctuations in the water content or impurities in the coating liquid for forming an antistatic layer or the coating film can be easily and quickly detected.

[0132] As the coating liquid for forming an antistatic layer, a coating liquid for forming an antistatic layer containing a known conductive composition can be used, and it is sufficient that it contains at least a solvent, a resin, and a non-reactive additive (a fluorescent marker compound).

[0133] Resin: Resins used in the coating liquid for forming an antistatic layer according to the present invention are preferably polyester resins, acrylic-modified polyester resins, polyurethane, acrylic resins, vinyl resins, vinylidene chloride resins, polyethyleneimine vinylidene resins, polyethyleneimine, polyvinyl alcohol, modified polyvinyl alcohol, cellulose ester resins, gelatin, etc. Details of these resins are as described in Japanese Patent No. 5,811,536.

[0134] <Solvent> The solvent contained in the coating liquid for forming the antistatic layer according to the present invention may be water or an organic solvent, and examples of the organic solvent include methyl ethyl ketone, acetone, and acetylacetone.

[0135] <<Non-reactive additives>> Examples of the non-reactive additives (fluorescent marker compounds) contained in the coating liquid for forming an antistatic layer according to the present invention include the above-mentioned antioxidants (e.g., Irganox 1076 (manufactured by BASF Japan)) and dyes (NIR dyes, NUV dyes), etc.

[0136] <Conductive Composition> Examples of the conductive composition contained in the coating liquid for forming an antistatic layer according to the present invention include polyaniline and derivatives thereof, preferably water-soluble sulfonated polyaniline, organic solvent-soluble polypyrrole, i.e., polypyrrole bonded with a long-chain alkyl group substituent, and polythiophene and derivatives thereof.

[0137] It is also preferable to use a metal oxide as the conductive composition. Examples of the metal oxide include ZnO and TiO. ２ , SnO ２ , Al ２ O ３ , In ２ O ３ , SiO ２ , MgO, BaO, MoO ２ , V ２ O ５ etc. or composite oxides thereof are preferred, and SnO ２ (tin oxide) is preferred. Examples of the oxide containing a different element include SnO ２ Sb, Nb, halogen elements, etc. can be added to the conductive composition. The amount of these foreign elements added is preferably in the range of 0.01 to 25 mol%, and more preferably in the range of 0.1 to 15 mol%. Specific examples of the conductive composition are as described in Japanese Patent No. 5811536.

[0138] (Application Example 4) Furthermore, the liquid material evaluation device of the present invention can also be applied during the process of forming a near-infrared reflective film. That is, it can be applied during the process of applying coating liquids for high refractive index layers and low refractive index layers formed on a transparent support. In this case, too, the coating liquid for the high refractive index layer or the low refractive index layer can be applied using a coating liquid application device (such as a gravure coater) in the same manner as in the above-mentioned Application Example 2. Specifically, in an apparatus for forming a high refractive index layer or a low refractive index layer, it is preferable to place the liquid material evaluation device of the present invention, for example, in the vicinity of the coating liquid application device or the transport roller immediately after applying the coating liquid for forming the high refractive index layer or the low refractive index layer, or in the vicinity of the transport roller during drying by a drying section after application or immediately after drying.

[0139] In this way, by placing the liquid material evaluation device of the present invention during the process of forming a high refractive index layer or a low refractive index layer, it is possible to measure, for example, the fluorescence spectrum of the coating liquid for forming a high refractive index layer or a low refractive index layer, or the applied coating film of the high refractive index layer or the low refractive index layer at any time, and any slight fluctuations in the water content or impurities in the coating liquid for forming a high refractive index layer or a low refractive index layer, or the coating film, can be easily and quickly detected.

[0140] As the coating liquid for forming a high refractive index layer and the coating liquid for forming a low refractive index layer, known coating liquids for forming a high refractive index layer and a low refractive index layer (see, for example, Japanese Patent No. 5593916) can be used, as long as they contain at least a solvent, a resin, and a non-reactive additive (a fluorescent marker compound).

[0141] Resin: Examples of the resin used in the coating solution for forming a high refractive index layer according to the present invention include hydrophilic resins. Examples of hydrophilic resins include water-soluble resins, water-dispersible resins, colloidal dispersion resins, and mixtures thereof. Specific examples of hydrophilic resins include acrylic, polyester, polyamide, polyurethane, and fluorine-based resins, such as polyvinyl alcohol, gelatin, polyethylene oxide, polyvinylpyrrolidone, casein, starch, agar, carrageenan, polyacrylic acid, polymethacrylic acid, polyacrylamide, polymethacrylamide, polystyrene sulfonic acid, cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, dextran, dextrin, pullulan, and water-soluble polyvinyl butyral. Among these, polyvinyl alcohol is preferred. The polymer used as the binder resin may be used alone, or two or more types may be mixed together as needed.

[0142] There is no particular restriction on the molecular weight of the polymer used as the binder resin of the high refractive index layer, but polyvinyl alcohol obtained by hydrolysis of vinyl acetate is preferably used with an average degree of polymerization of 1000 or more, particularly preferably 1500 to 5000. Furthermore, the saponification degree is preferably 70 to 100%, particularly preferably 80 to 99.5%.

[0143] <<Solvent>> When a water-soluble resin is used, a mixture containing water as the main component as the solvent, and optionally containing a hydrophilic organic solvent, can be used.

[0144] Examples of hydrophilic solvents include alcohols such as methanol, ethanol, 2-propanol, and 1-butanol, esters such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate, ethers such as diethyl ether, propylene glycol monomethyl ether, and ethylene glycol monoethyl ether, amides such as dimethylformamide and N-methylpyrrolidone, ketones such as acetone, methyl ethyl ketone, acetylacetone, and cyclohexanone, aromatic hydrocarbons such as benzene, toluene, and xylene, and aliphatic hydrocarbons such as heptane, hexane, pentane, decane, and cyclohexane, and one or more of these can be used. From an environmental perspective, the use of water or alcohols is particularly preferred as the solvent for the coating solution.

[0145] <<Non-reactive additives>> Examples of the non-reactive additives (fluorescent marker compounds) contained in the coating liquid for forming a high refractive index layer according to the present invention include the above-mentioned antioxidants (e.g., Irganox 1076 (manufactured by BASF Japan Ltd.)) and dyes (NIR dyes, NUV dyes), etc.

[0146] <<Metal Oxide>> The coating liquid for forming a high refractive index layer according to the present invention preferably contains a metal oxide. Examples of such metal oxides include TiO ２ (Titanium oxide), SiO ２ , ZrO ２ , Al ２ O ３ , ZnO, Sb２ O ３ , ZrSiO ４ , zeolite, etc.

[0147] As the coating liquid for forming a low refractive index layer, a known coating liquid for forming a low refractive index layer can be used, and it is sufficient that it contains at least a solvent, a resin, and a non-reactive additive (fluorescent marker compound).

[0148] <<Resin>> As the resin contained in the coating liquid for forming the low refractive index layer, a small amount of the hydrophilic binder resin contained in the coating liquid for forming the high refractive index layer described above can be used.

[0149] <<Solvent>> The solvent contained in the coating liquid for forming the low refractive index layer may also be the same as the solvent contained in the coating liquid for forming the high refractive index layer.

[0150] <<Non-reactive additives>> Examples of the non-reactive additives (fluorescent marker compounds) contained in the coating liquid for forming a low refractive index layer according to the present invention include the above-mentioned antioxidants (e.g., Irganox 1076 (manufactured by BASF Japan Ltd.)) and dyes (NIR dyes, NUV dyes), etc.

[0151] <<Metal Oxide>> The coating liquid for forming a low refractive index layer according to the present invention also preferably contains the metal oxide contained in the coating liquid for forming a high refractive index layer described above.

[0152] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these. In the following examples, unless otherwise specified, operations were carried out at room temperature (25°C). Furthermore, unless otherwise specified, "%" and "parts" mean "% by mass" and "parts by mass", respectively.

[0153] [Sample 1] (Resin 1) A hydrogenated norbornene resin ("Arton G7810" manufactured by JSR Corporation) was used as a resin containing a cycloolefin polymer. Hereinafter, this cycloolefin resin will be referred to as "COP."

[0154] (Preparation of Liquid 1) Liquid 1 (dope for optical film) having the following composition was prepared. First, dichloromethane was added to a pressure dissolution tank. Next, COP was added to the pressure dissolution tank with stirring. Next, an antioxidant ("Irganox 1076" manufactured by BASF Japan Ltd.) was added as a fluorescent marker compound and completely dissolved with stirring. COP: 100 parts by mass, dichloromethane: 280 parts by mass, Irganox 1076: 100 ppm by mass

[0155] [Sample 2] (Preparation of Liquid Material 2) Liquid material (dope for optical film) 2 was prepared in the same manner as in the preparation of Liquid Material 1, except that the solvent (dichloromethane) was not added.

[0156] [Sample 3] (Preparation of Liquid Material 3) Liquid material (dope for optical film) 3 was prepared in the same manner as in the preparation of Liquid Material 1, except that COP was not added.

[0157] [Sample 4] (Preparation of Liquid 4) Liquid 4 (dope for optical film) was prepared in the same manner as in the preparation of Liquid 1, except that the fluorescent marker compound was changed to Elecut S-418 (manufactured by Takemoto Yushi Co., Ltd.) (reaction additive: chelating agent).

[0158] [Sample 5] (Preparation of Liquid Material 5) Liquid material (dope for optical film) 5 having the following composition was prepared. First, dichloromethane and ethanol (92% by mass of dichloromethane, 8% by mass of ethanol) were added to a pressure dissolution tank. Next, COP was added to the pressure dissolution tank with stirring. Next, an antioxidant ("Irganox 1076" manufactured by BASF Japan Ltd.) was added as a fluorescent marker compound and completely dissolved with stirring. COP: 100 parts by mass, dichloromethane: 260 parts by mass, ethanol: 22 parts by mass, Irganox 1076: 100 ppm by mass

[0159] [Sample 6] (Preparation of Liquid Material 6) Liquid material (dope for optical film) 6 was prepared in the same manner as in preparation of Liquid Material 5, except that the resin was changed to cellulose acylate (acetyl group substitution degree: 2.80).

[0160] [Sample 7] (Preparation of Liquid Material 7) Liquid material (dope for optical film) 7 was prepared in the same manner as in preparation of Liquid Material 5, except that the resin was changed to Delpet 80N (manufactured by Asahi Kasei Chemicals Corporation, polymethyl methacrylate).

[0161] [Sample 8] (Preparation of Liquid 8) Liquid (dope for optical film) 8 was prepared in the same manner as in the preparation of Liquid 5, except that the fluorescent marker compound was changed to the following compound A (NIR dye) (100 mass ppm).

[0162]

[0163] [Sample 9] (Preparation of Liquid 9) Liquid (dope for optical film) 9 was prepared in the same manner as in the preparation of Liquid 5, except that the fluorescent marker compound was changed to the following compound B (NUV dye) (100 mass ppm).

[0164]

[0165] [Sample 10] (Preparation of Liquid Material 10) Liquid material (dope for optical film) 10 was prepared with the same composition as liquid material 5.

[0166] [Sample 11] (Preparation of Liquid Material 11) Liquid material (dope for optical film) 11 was prepared in the same manner as in the preparation of Liquid Material 5, except that the amount of the fluorescent marker compound added was 5000 ppm by mass.

[0167] [Sample 12] (Preparation of Liquid Material 12) Liquid material (dope for optical film) 12 was prepared in the same manner as in the preparation of Liquid Material 5, except that the amount of the fluorescent marker compound added was 10,000 ppm by mass.

[0168] [Samples 13 to 15 and 17] (Preparation of Liquids 13 to 15 and 17) Liquids (dopes for optical films) 13 to 15 and 17 were prepared with the same composition as Liquid 5.

[0169] [Sample 16] (Preparation of Liquid Material 16) Liquid material (dope for optical film) 16 was prepared with the same composition as liquid material 9.

[0170] [Samples 18 and 19] (Preparation of Liquids 18 and 19) Liquids (dopes for optical films) 18 and 19 were prepared with the same composition as that of Liquid 8.

[0171] [Sample 20] (Preparation of Liquid Material 20) Beamset 577 (manufactured by Arakawa Chemical Industries, Ltd.) (urethane resin) was used as the ultraviolet curable resin, and methyl ethyl ketone (MEK) was added as the solvent. Furthermore, 0.08 mass % of a fluorine-based surfactant (trade name: Futergent (registered trademark) 650A, manufactured by Neos Corporation) was added, and then 100 mass ppm of Irganox 1076 was added as a fluorescent marker compound, and the total solid content was adjusted to 40 mass parts, thereby producing a liquid material (coating liquid for forming a hard coat layer) 20.

[0172] [Sample 21] (Preparation of Liquid Material 21) While 10 parts by mass of a 3% by mass aqueous solution of boric acid was heated and stirred at 45°C, 80 parts by mass of a 5% by mass aqueous solution of polyvinyl alcohol (PVA-117H, degree of polymerization 1700, degree of saponification 99.5 mol%, manufactured by Kuraray Co., Ltd.) was added as a resin, and then 1 part by mass of a 1% by mass aqueous solution of a surfactant (Rapisol A30, manufactured by NOF Corporation) was added, and 9 parts by mass of pure water was added as a solvent, and then 100 ppm by mass of Irganox 1076 was added as a fluorescent marker agent, thereby preparing a liquid material (coating liquid for forming a low refractive index layer) 21.

[0173] [Evaluation] <Sensitivity of peak intensity shift> For each of the liquids prepared above, a group of fluorescence spectra was measured in advance using a spectrophotometer, with the excitation wavelength changed in 5 nm increments, and the excitation wavelength showing the most intense fluorescence spectrum was selected as the excitation wavelength effective for measurement. The spectrophotometer used was a spectrofluorometer F-7100 (manufactured by Hitachi High-Tech Science Corporation). For liquids 1 to 3, 5 to 7, 11, and 12, which used Irganox 1076 as the fluorescent marker compound, 280 nm was selected as the excitation wavelength effective for measurement. In addition, Irganox 1076 was used as the fluorescent marker compound, and for liquid material 10, in which the test object was magnesium ions, the effective excitation wavelength for measurement was 330 nm; for liquid material 13, in which the test object was benzene, the effective wavelength for measurement was 270 nm; for liquid material 14, in which the test object was acetone, the effective wavelength for measurement was 260 nm; for liquid material 15, in which the test object was strontium chloride, the effective wavelength for measurement was 250 nm; for liquid material 17, in which the test object was methanol, the effective wavelength for measurement was 290 nm; and for liquids 20 and 21, in which the test object was sodium ions, the effective excitation wavelength for measurement was 300 nm. Furthermore, using compound A, an effective excitation wavelength for measurement was selected as 680 nm for liquid 8, in which the test object was water, as an effective wavelength for measurement was 690 nm for liquid 18, in which the test object was formamide, and as an effective wavelength for measurement was 700 nm for liquid 19, in which the test object was magnesium chloride. Furthermore, using compound B, an effective excitation wavelength for measurement was selected as 330 nm for liquid 9, in which the test object was water, and as an effective wavelength for measurement was selected as 340 nm for liquid 16, in which the test object was ethanol.

[0174] Next, for each liquid, the test object shown in the table below was used. When the test object was water, water was added so that the water content was 0.1% by mass and 1.0% by mass. When the test object was magnesium ions or sodium ions, magnesium ions or sodium ions were added so that the magnesium ion or sodium ion content was 0.01% by mass and 0.1% by mass. Here, in the case of magnesium ions, MgCl ２In the case of sodium ions, NaCl was added. Furthermore, when the test object was benzene, acetone, or formamide, benzene, acetone, or formamide was added so that the benzene, acetone, or formamide content was 0.1% by mass and 1.0% by mass. When the test object was strontium chloride, strontium chloride was added so that the strontium chloride content was 0.01% by mass and 0.1% by mass. When the test object was ethanol or methanol, ethanol or methanol was added so that the ethanol or methanol content was 1% by mass and 10% by mass. Next, for each liquid containing the test object, light of the effective excitation wavelength was irradiated to measure the fluorescence spectrum, and the fluorescence wavelength and peak intensity at the peak top were measured. The change in fluorescence wavelength and the change in peak intensity (peak intensity shift) due to changes in the test object content were calculated, and the resulting peak intensity shift was evaluated according to the following criteria. A, AA, and AAA in the following criteria were considered to be acceptable levels for practical use. (Criteria) AAA: The change in fluorescence wavelength exceeds 3.0%, and the change in peak intensity exceeds 5.0%. AA: The change in fluorescence wavelength is more than 1.5% and not more than 3.0%, and the change in peak intensity is more than 1.0% and not more than 5.0%. A: The change in fluorescence wavelength is more than 0.3% and not more than 1.5%, and the change in peak intensity is more than 0.1% and not more than 1.0%. B: The change in fluorescence wavelength is not more than 0.3%, and the change in peak intensity is not more than 0.1%.

[0175] <Haze Value> The haze of the films obtained one hour after starting production of the films using liquid materials 1 to 14 was measured using a haze meter (NDH manufactured by Nippon Denshoku Industries Co., Ltd.). The measured haze was then evaluated according to the following criteria. The following criteria of A, AA, and AAA were determined to be levels that are acceptable for practical use. AAA: Haze is 0.1% or less. AA: Haze is greater than 0.1% and less than 0.5%. A: Haze is greater than 0.5% and less than 1%. B: Haze is greater than 1%.

[0176] The SP values ​​and ΔSP of the solvents, resins, marker compounds and test objects used in the preparation of each sample were calculated by the above-mentioned methods and are shown in the table below.

[0177]

[0178]

[0179] As shown by the above results, it is recognized that the use of the liquid material evaluation method of the present invention provides superior sensitivity to the peak intensity shift degree and reduces the variation in film quality compared to the comparative example.

[0180] The present invention can be used in a liquid evaluation method and liquid evaluation device that can constantly detect minute fluctuations in the water content, impurities, etc. in a liquid without using a reactive fluorescent marker agent.

[0181] REFERENCE SIGNS LIST 1 Dissolving vessel 3, 6, 12, 15 Filter 4, 13 Stock vessel 2, 5, 11, 14 Liquid transfer pump 8, 16 Conduit 10 Additive supply vessel 20 Confluence pipe 21 Mixer 30 Pressure die 31 Metal support 32 Web 33 Peeling position 34 Stretching device 35 Drying device 36 Conveying roller 37 Winding device 41 Supply vessel 42 Stock vessel 43 Pump

Claims

1. A method for evaluating a liquid material containing at least a solvent, a resin, and a non-reactive additive, comprising the steps of: the non-reactive additive is a fluorescent marker compound; a fluorescence spectrum observation step of acquiring a fluorescence spectrum of the liquid at an arbitrary excitation wavelength; and a spectral analysis step of acquiring data on a degree of peak intensity shift from the acquired fluorescence spectrum based on an interaction between the fluorescent marker compound in the liquid and a test object.

2. 2. The method for evaluating a liquid material according to claim 1, wherein a difference in solubility parameter ΔSP between the fluorescent marker compound and the test object in the liquid material is within a range of 6 to 22.

3. The method for evaluating a liquid material according to claim 1, wherein the non-reactive additive is contained in the liquid material in an amount within a range of 1 to 5,000 ppm by mass.

4. The method for evaluating a liquid substance according to claim 1 , wherein the spectral analysis step is performed in-line.

5. The method for evaluating a liquid material according to claim 1 , further comprising a data processing step of calculating a content of the test object using a calibration curve based on peak intensities included in the data relating to the degree of peak intensity shift.

6. An evaluation device for a liquid material containing at least a solvent, a resin, and a non-reactive additive, the non-reactive additive is a fluorescent marker compound; a fluorescence spectrum observation unit for acquiring a fluorescence spectrum of the liquid at an arbitrary excitation wavelength; and a spectrum analysis unit that acquires data on a peak intensity shift degree from the acquired fluorescence spectrum based on an interaction between the fluorescent marker compound in the liquid and an object to be tested.

7. The liquid material evaluation device according to claim 6 , further comprising a data processing unit that calculates a content of the test object using a calibration curve based on a peak intensity included in the data relating to the peak intensity shift degree.

8. The liquid material evaluation device according to claim 6 or 7, further comprising an information display unit that displays data relating to the peak intensity shift degree.