JP7213503B2 - Inspection method for surface-modified substrate - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing a surface-modified substrate, a surface-modified substrate manufactured by the method, and an inspection method for the same.

As a method of modifying a substrate, a method of forming a physically or chemically bonded polymer layer on the surface of a substrate by allowing a polymer having a group capable of adsorbing or reacting with the substrate at its end to act on the substrate. It has been known. Also known is a method of forming a polymer layer grafted from the substrate surface by polymerizing a monomer starting from a polymerizable group imparted to the substrate surface.

In recent years, so-called "dense polymer brushes", which are grafted onto a substrate at high density using the technique of living radical polymerization developed in the 1990s, have been studied. In this dense polymer brush, polymer chains are grafted onto the substrate at a high density with 1-4 nm spacing. Such dense polymer brushes can be used to modify the surface of the substrate and impart characteristics such as low friction, suppression of protein adsorption, size exclusion properties, hydrophilicity, and water repellency (for example, Patent Documents 1 and 2). , Non-Patent Documents 1-3).

JP 2008-133434 A Japanese Patent Application Laid-Open No. 2010-261001

Adv. Polym. Sci. , 2006, 197, 1-45 J. Am. Chem. Soc. , 2005, 127, 15843-15847 Polym. Chem. , 2012, 3, 148-153

However, the polymer layer formed on the substrate surface is often as thin as nano- to micron-sized and transparent. Therefore, in order to measure the thickness of the polymer layer, it is necessary to use an atomic force microscope, ellipsometry, or the like, so there is a problem that the analysis takes time and effort. There is also a method of measuring the thickness of the polymer layer by observing scratches on a portion of the polymer layer with an electron microscope or the like, but this method can only measure the thickness of a portion of the polymer layer. Moreover, since the surface-treated base material is an industrial part that is industrially mass-produced, it is necessary to inspect the entire amount in order to confirm that a certain quality is maintained. However, it is difficult for the above thickness measuring method and the like to correspond to the total inspection.

The present invention has been made in view of the problems of the prior art, and an object of the present invention is to provide a polymer layer that allows easy confirmation of the presence and degree of defects such as scratches and defects. To provide a method for producing a surface-modified substrate having on its surface. In addition, the object of the present invention is to provide a surface-modified surface having a polymer layer on its surface that can easily check the presence or absence and degree of defects such as scratches and defects, which is manufactured by the above-described manufacturing method. It is to provide a base material. A further object of the present invention is to provide a method for inspecting the above surface-modified substrate.

That is, according to the present invention, the following method for producing a surface-modified substrate is provided.
[1] Under pressure conditions of 100 to 1,000 MPa, in the presence of a base material to which a polymerization initiating group is bonded, a monomer containing a radically polymerizable fluorescent dye undergoes surface-initiated radical polymerization or surface-initiated living radical polymerization, and the base material is A method for producing a surface-modified substrate, comprising the step of forming a fluorescent polymer layer having a thickness of 100 nm or more comprising a fluorescent polymer bonded to the surface of
[2] Furthermore, surface-initiated radical polymerization or surface-initiated living radical polymerization is performed in the coexistence of an initiating group monomer having the same initiating group as the polymerization initiating group to form a free polymer that is not contained in the fluorescent polymer layer. The method for producing a surface-modified substrate according to [1] above, wherein the molecular weight of the fluorescent polymer is estimated from the molecular weight of the formed free polymer.
[3] The method for producing a surface-modified substrate according to [1] or [2], wherein the polymerization initiation group is represented by the following general formula (1) or (2).

（前記一般式（１）中、Ｘは、塩素原子、臭素原子、又はヨウ素原子を示し、Ｒ_１は、水素原子、アルキル基、アリール基、シアノ基、アシル基、カルボキシ基、エステル基、又はアミド基を示し、Ｒ_２は、アルキル基、アリール基、シアノ基、アシル基、カルボキシ基、エステル基、又はアミド基を示し、「＊」は結合位置を示す）

(In the general formula (1), X represents a chlorine atom, a bromine atom, or an iodine atom, and R ₁ represents a hydrogen atom, an alkyl group, an aryl group, a cyano group, an acyl group, a carboxy group, an ester group, or represents an amide group, R ₂ represents an alkyl group, an aryl group, a cyano group, an acyl group, a carboxy group, an ester group, or an amide group, and "*" represents a bonding position)

（前記一般式（２）中、Ｘは、塩素原子、臭素原子、又はヨウ素原子を示し、Ｙは、Ｏ又はＮＨを示し、Ｒ_３は、水素原子、アルキル基、アリール基、又はアシル基を示し、Ｒ_４は、アルキル基、アリール基、又はアシル基を示し、「＊」は結合位置を示す）

(In the general formula (2), X represents a chlorine atom, a bromine atom, or an iodine atom, Y represents O or NH, and R ₃ represents a hydrogen atom, an alkyl group, an aryl group, or an acyl group. shown, R ₄ represents an alkyl group, an aryl group, or an acyl group, and "*" represents the bonding position)

[4] Further, in the presence of at least one salt selected from the group consisting of quaternary ammonium halide salts, quaternary phosphonium halide salts, and alkali metal halide salts, surface-initiated radical polymerization or surface-initiated The method for producing a surface-modified substrate according to any one of [1] to [3], wherein living radical polymerization is performed.
[5] The method for producing a surface-modified substrate according to any one of [1] to [4], wherein the radically polymerizable fluorescent dye is a monomer having a (meth)acryloyloxy group.

Further, according to the present invention, the following surface-modified substrate is provided.
[6] A surface-modified substrate produced by the production method according to any one of [1] and [3] to [5].

Furthermore, according to the present invention, there is provided a method for inspecting a surface-modified substrate as described below.
[7] A surface-modifying group having a step of confirming the state of the fluorescent polymer layer by fluorescence generated by irradiating the fluorescent polymer layer of the surface-modified substrate according to [6] with ultraviolet rays. Material inspection method.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the surface modification base material provided with the polymer layer which can confirm easily the presence or absence and grade of defects, such as a crack and a defect, on the surface can be provided. Further, according to the present invention, there is provided a surface-modified substrate having a polymer layer on its surface, which is manufactured by the above-described manufacturing method and allows easy confirmation of the presence or absence and degree of defects such as scratches and defects. can provide. Furthermore, according to the present invention, it is possible to provide a method for inspecting the above surface-modified substrate.

<Surface modified substrate and method for producing the same>
Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments. The method for producing a surface-modified substrate of the present invention comprises surface-initiated radical polymerization of a monomer containing a radically polymerizable fluorescent dye in the presence of a substrate to which a polymerization initiation group is bonded under normal pressure to 1,000 MPa pressure conditions. Alternatively, it has a step of surface-initiated living radical polymerization to form a fluorescent polymer layer composed of a fluorescent polymer bonded to the surface of the substrate (polymerization step). Moreover, the surface-modified substrate of the present invention is manufactured by the above manufacturing method. Details of the surface-modified substrate and the method for producing the same of the present invention will be described below.

Conventionally, a method of modifying the surface of a base material by grafting a vinyl polymer onto the surface of the base material is known. As a method of grafting a polymer onto the substrate surface, for example, there is a so-called surface-initiated polymerization method in which a polymer is polymerized from the substrate surface. The surface-initiated polymerization method includes a method of initiating polymerization from radicals generated by irradiating the substrate surface with radiation or the like; a method of initiating polymerization from a compound having an azo group or a peroxide group introduced to the substrate surface. ;and so on. On the other hand, in the method for producing a surface-modified substrate of the present invention, a substrate having a polymerization initiating group, which is a radical-generating group, bonded to its surface is used, and radical polymerization or living radicals are produced from the polymerization initiating group. Polymerization grafts the polymer to form a polymer layer on the surface of the substrate.

(Base material)
The type of base material is not particularly limited, and any of natural materials, artificial materials, inorganic members, and organic members can be used. In addition, substrates of various shapes such as lumps, powders, sheets, films, pellets and plates can be used. Among them, it is preferable to use a substrate that can withstand the polymerization solution. Specific examples of the substrate include metals, metal oxides, metal nitrides, metal carbides, ceramics, wood, silicon compounds, thermoplastic resins, thermosetting resins, cellulose, films such as glass, fibers, and sheets. be able to.

The substrate may be surface-treated. Surface treatments include inorganic treatments such as silane coupling treatment, silica coating treatment and silica alumina treatment; plasma treatment, ultraviolet irradiation treatment, ozone oxidation treatment, radiation treatment, X-ray treatment, electron beam treatment and laser treatment. An activation process etc. can be mentioned.

(Polymerization initiating group)
As the polymerization initiation group, an initiation group used in ordinary (living) radical polymerization can be used. Living radical polymerization includes the NMP method in which radicals are generated by thermally dissociating a nitroxide compound as an initiating compound; atom transfer radical polymerization performed by redox using a compound having a halogen group as an initiating compound and a metal complex of copper or ruthenium as a catalyst. (ATRP method); reversible addition-fragmentation chain transfer polymerization (RAFT method) using a compound having a dithioester group; TERP method using an organic tellurium as an initiating compound; a compound having an iodine group as an initiating compound and iodine as a catalyst Reversible transfer catalyst polymerization (RTCP method) using an organic compound that can abstract as a radical as a catalyst; reactive catalyst-mediated polymerization (RCMP method); halogen exchange polymerization; Using a base material with the initiating group used in these polymerization methods introduced onto its surface, the fluorescent polymer was bonded (grafted) to the surface of the base material by (living) radical polymerization with the initiating group as the starting point. A fluorescent polymer layer can be formed.

In the case of the NMP method using a nitroxide compound, the TERP method using an organic tellurium compound, and the RAFT method using a compound having a dithioester group, the starting compounds are special and are not very cost effective. Absent. Therefore, it is preferable to use a polymerization initiation group represented by the following general formula (1) or (2). X in the general formula (1) or (2) is eliminated as a radical, and a monomer is inserted as a generated carbon radical for polymerization. This forms a polymer terminated with the initiating group.

（前記一般式（１）中、Ｘは、塩素原子、臭素原子、又はヨウ素原子を示し、Ｒ_１は、水素原子、アルキル基、アリール基、シアノ基、アシル基、カルボキシ基、エステル基、又はアミド基を示し、Ｒ_２は、アルキル基、アリール基、シアノ基、アシル基、カルボキシ基、エステル基、又はアミド基を示し、「＊」は結合位置を示す）

(In the general formula (1), X represents a chlorine atom, a bromine atom, or an iodine atom, and R ₁ represents a hydrogen atom, an alkyl group, an aryl group, a cyano group, an acyl group, a carboxy group, an ester group, or represents an amide group, R ₂ represents an alkyl group, an aryl group, a cyano group, an acyl group, a carboxy group, an ester group, or an amide group, and "*" represents a bonding position)

In general formula (1), the carbon atom to which X is bonded is a tertiary carbon atom or a quaternary carbon atom. At least one of R ₁ and R ₂ is preferably a group other than an alkyl group. That is, when at least one of R ₁ and R ₂ is an electron-donating group other than an alkyl group, X becomes easier to leave. Among them, it is more preferable for X to be bonded to a quaternary carbon atom to generate a radical.

（前記一般式（２）中、Ｘは、塩素原子、臭素原子、又はヨウ素原子を示し、Ｙは、Ｏ又はＮＨを示し、Ｒ_３は、水素原子、アルキル基、アリール基、又はアシル基を示し、Ｒ_４は、アルキル基、アリール基、又はアシル基を示し、「＊」は結合位置を示す）

(In the general formula (2), X represents a chlorine atom, a bromine atom, or an iodine atom, Y represents O or NH, and R ₃ represents a hydrogen atom, an alkyl group, an aryl group, or an acyl group. shown, R ₄ represents an alkyl group, an aryl group, or an acyl group, and "*" represents the bonding position)

In general formula (2), the carbon atom to which X is bonded is a tertiary carbon atom or a quaternary carbon atom. Both R ₃ and R ₄ may be alkyl groups, as ester or amide groups are electron donating groups. Also, it is more preferable for X to be attached to a quaternary carbon atom to generate a radical.

As a method for introducing (bonding) the polymerization initiation group to the surface of the substrate, for example, a compound having a polymerization initiation group is applied to the substrate by a method such as coating, vapor deposition, transfer, electrodeposition, lamination, or formation of a single layer film. A method of giving to can be mentioned. Among them, it is preferable to apply a compound having a polymerization initiating group and a group that reacts with the substrate, or a polymer having a polymerization initiating group to the substrate. As the polymer having a polymerization initiation group, a polymer having a three-dimensional crosslinked structure and a polymer further having a group that reacts with the substrate are preferable. By applying a compound or polymer having a group that reacts with the base material to the base material, the polymerization initiation group can be firmly introduced to the base material surface.

The reactive group may be appropriately selected according to the type of substrate. For example, when a silicon substrate, a metal, a metal oxide, an inorganic compound having a hydroxyl group, or the like is used as the base material, an alkoxysilyl group, an epoxy group, or the like is preferable as the reactive group. When an organic compound having a hydroxyl group such as cellulose is used as the base material, acid halides, acid anhydrides, isocyanate groups and the like are preferred as reactive groups.

As the polymer having a polymerizable group, a monomer represented by the following general formula (3) and a monomer having an alkoxysilyl group such as (meth)acryloyloxypropyltrimethylsilyl or (meth)acryloyloxypropyltriethoxysilyl It is preferable to use a polymer (polymer-type treatment agent) obtained by polymerizing a monomer component containing .

As the compound having a polymerization initiating group, it is preferable to use a compound having a polymerization initiating group and a group (alkoxysilyl group) that reacts with the substrate represented by the following formula (4).

(Radical polymerizable fluorescent dye)
A radically polymerizable fluorescent dye is a fluorescent dye having a radically polymerizable group containing an unsaturated bond or the like. By polymerizing a monomer containing such a radically polymerizable fluorescent dye, it is possible to form a fluorescent polymer layer composed of the fluorescent polymer bound to the surface of the substrate. Radically polymerizable fluorescent dyes include merocyanine-based fluorescent dyes, perylene-based fluorescent dyes, acridine-based fluorescent dyes, luciferin-based fluorescent dyes, pyranine-based fluorescent dyes, stilbene-based fluorescent dyes, rhodami-based fluorescent dyes, coumarin-based fluorescent dyes, and azo-based fluorescent dyes. Organic dyes such as fluorescent dyes, pyran-based fluorescent dyes, pyrromethene-based fluorescent dyes, fluorescein-based fluorescent dyes, and umbelliferone-based fluorescent dyes; and inorganic dyes such as europium-based dyes.

More specific examples of radically polymerizable fluorescent dyes include monomers having a (meth)acryloyloxy group represented by the following general formulas (5) to (11) (R represents a hydrogen atom or a methyl group): be able to. Moreover, R in the following general formulas (5) to (11) is preferably a methyl group.

Although all of the monomers to be polymerized may be radically polymerizable fluorescent dyes, it may become difficult to emit light due to concentration quenching or the like, or may remain without reaction due to bulky monomers. In addition, since the radically polymerizable dye has a high emission intensity, it emits strong light even when the amount used is small. Therefore, the amount of the radically polymerizable fluorescent dye in all monomers is preferably 0.01 to 10% by mass, more preferably 0.1 to 5% by mass.

(Monomers other than radically polymerizable fluorescent dyes)
As the monomer (other monomer) other than the radically polymerizable fluorescent dye, any conventionally known monomer capable of radical polymerization can be used, and the monomer is appropriately selected and used according to the characteristics of the fluorescent polymer layer to be formed. Just do it. Among them, it is preferable to use a monomer having a (meth)acryloyloxy group ((meth)acrylate-based monomer), and it is more preferable to use a monomer having a methacryloyloxy group (methacrylate-based monomer).

(Polymerization method)
In the polymerization step, the monomer containing the radically polymerizable fluorescent dye is subjected to radical polymerization or living radical polymerization. Further, when a group having a halogen atom such as the group represented by the general formula (1) or (2) is used as the polymerization initiation group, it is preferable to polymerize the monomer by atom transfer radical polymerization using a conventionally known metal complex. . Examples of metal complexes include complexes of copper chloride or copper bromide with polyamines such as dinonylbipyridine, tridimethylaminoethylamine and pentamethyldiethylenetriamine; dichlorotris(triphenylphosphine)ruthenium; and the like. Atom transfer radical polymerization may be bulk polymerization or solution polymerization using an organic solvent or the like. Examples of organic solvents that can be used include hydrocarbon-based solvents, ester-based solvents, glycol-based solvents, ether-based solvents, amide-based solvents, alcohol-based solvents, sulfoxide-based solvents, urea-based solvents, and ionic liquids.

Since heavy metals are used in atom transfer radical polymerization, it is necessary to consider their coloring and load on the environment, and also to remove them from the reaction system. Therefore, it is preferable to polymerize in the presence of a general-purpose organic compound that does not use heavy metals. Specifically, the radically polymerizable fluorescent dye and ( It is preferred to polymerize monomers including meth)acrylate monomers. As a result, it is possible to polymerize with commercially available inexpensive organic materials and inorganic salts. In addition, since there is no need to remove metal, the load on the environment can be reduced and the process can be simplified.

X (halogen) in the polymerization initiating group is eliminated as a radical, and the monomer is inserted into the carbon radical generated as X is eliminated to proceed with polymerization. At that time, the coexistence of the specific salt described above causes abstraction of halogen radicals or halogen exchange, and polymerization of monomers proceeds from the generated carbon radicals to form a fluorescent polymer.

Halogenated quaternary ammonium salts include benzyltrimethylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetraoctylammonium iodide, nonylpyridinium chloride, choline chloride and the like. Halogenated quaternary phosphonium salts include tetraphenylphosphonium chloride, methyltributylphosphonium bromide, and tetrabutylphosphonium iodide. Examples of alkali metal halide salts include lithium bromide and potassium iodide.

As the salt, it is preferable to use an iodide salt. By using an iodide salt, living radical polymerization proceeds and a polymer with a narrower molecular weight distribution can be obtained. In addition, it is preferable to use a salt soluble in the polymerization solution such as a quaternary ammonium iodide salt, a quaternary phosphonium iodide salt, and an alkali metal iodide salt, and a quaternary ammonium iodide salt is preferably used. More preferred. Examples of quaternary ammonium iodide salts include benzyltetrabutylammonium iodide, tetrabutylammonium iodide, tetraoctylammonium iodide, dodecyltrimethylammonium iodide, octadecyltrimethylammonium iodide, triocdacdecylmethylammonium iodide, and the like. can be mentioned.

From the viewpoint of increasing the activity and obtaining a polymer with a higher concentration and a higher molecular weight, the amount of the salt to the polymerization initiating group is preferably equal to or more than the molar amount, more preferably 10 times the molar amount or more, and more preferably 100 times the molar amount or more. may be

In the method using this quaternary salt or halide salt, the polymerization conditions are not particularly limited. It is carried out under conventionally known conditions. Preferably, the temperature is above 60° C. and an organic solvent is used as the solvent. Conventionally known solvents can be used as the solvent, and there is no particular limitation. As the solvent, conventionally known organic solvents can be used, but it is preferable to use a solvent that dissolves salts. Organic solvents with high . are preferred.

In the polymerization step, polymerization is carried out under normal pressure to 1,000 MPa, preferably 100 to 1,000 MPa, more preferably 200 to 800 MPa, particularly preferably 300 to 600 MPa. Specifically, the entire polymerization vessel containing the monomer and the base material is polymerized while uniformly applying pressure via a medium such as water. Radical polymerization under pressure can suppress the termination reaction and form a fluorescent polymer having a higher molecular weight.

Radical polymerization under a pressure condition, preferably at a pressure of 100 MPa or more, can suppress the termination reaction and form a fluorescent polymer with a higher molecular weight. It should be noted that it is difficult and impractical to prepare a container or apparatus that can withstand a pressure of over 1,000 MPa. As the molecular weight of the fluorescent polymer formed increases, the film thickness of the fluorescent polymer layer formed on the substrate surface increases. By increasing the thickness of the fluorescent polymer layer, the substrate surface can be modified to exhibit unprecedented properties. The film thickness of the fluorescent polymer layer can be, for example, several nm to several μm, preferably 10 nm or more, more preferably 100 nm or more.

As the polymerization vessel, it is preferable to use a vessel that can be sealed and that can withstand high pressure. In addition, since it is necessary to transmit pressure to the inside of the container, it is preferable to use a container having a portion that is deformed by pressure, such as a plastic soft portion or an elastic portion. Specifically, various containers such as polyethylene bottles, PET bottles, retort pouches, and blister containers can be used. Also, a container made of a heat-resistant material that is resistant to deformation at the temperature during polymerization is preferable. Furthermore, it is preferable to use a container made of a material having properties such as chemical resistance and solvent resistance, which is resistant to being attacked by a solvent for polymerization or the like. Examples of materials constituting the polymerization vessel include polyolefin resins, fluorine resins, polyester resins, polyamide resins, engineering plastics, and the like. During polymerization, it is preferable to prevent gas from entering the polymerization vessel as much as possible. For example, it is preferable to charge the polymerization solution to 90% or more of the volume of the polymerization vessel.

By appropriately selecting and using a monomer (other monomer) other than the radically polymerizable fluorescent dye, the properties of the fluorescent polymer layer to be formed can be arbitrarily set. For example, by using a fluorine-based monomer as another monomer, it is possible to form a fluorescent polymer layer that easily repels water and oil and has a low surface tension. In addition, by using a monomer having a polyethylene glycol group, a carboxy group, or the like as another monomer, it is possible to form a hydrophilic fluorescent polymer layer in which impinging water vapor immediately turns into water droplets and is less likely to cloud. Furthermore, it is also possible to produce a biocompatible substrate to which proteins and the like are less likely to adhere. Further, the formed fluorescent polymer layer may be swollen with lubricating oil or the like to form a lubricating film, thereby forming an extremely low-friction polymer layer.

As will be described later, the formed polymer layer is a fluorescent polymer layer that emits fluorescence when irradiated with ultraviolet rays. Therefore, the presence or absence and degree of defects such as scratches and defects in the polymer layer can be easily determined by irradiation with ultraviolet rays. can be confirmed. However, while it is possible to confirm the presence or absence and degree of defects in the polymer layer, it cannot be said that it is easy to verify the molecular weight of the fluorescent polymer that constitutes the formed fluorescent polymer layer. Therefore, in the production method of the present invention, it is preferable to carry out surface-initiated radical polymerization or surface-initiated living radical polymerization in the coexistence of an initiating group monomer having the same initiating group as the polymerization initiating group. That is, a free polymer that is not contained in the fluorescent polymer layer is formed by radically polymerizing an initiating group monomer that exists free without bonding to the substrate. By measuring the molecular weight of the formed free polymer according to a standard method, the molecular weight of the fluorescent polymer forming the fluorescent polymer layer formed on the substrate surface can be estimated.

As the initiating group monomer, a compound having the same group as the polymerization initiating group bonded to the substrate is used. Specifically, compounds represented by the following formulas (12) to (14) can be used as initiating group monomers.

The amount of the initiating group monomer in the polymerization system is preferably 0.01% by mass or less, more preferably 0.001% by mass or less. If the amount of the initiating group monomer is too large, the viscosity of the polymerization system increases, and it may become difficult to take out the obtained surface-modified base material. In addition, it may take time to wash and remove the free polymer formed from the initiating group monomer attached to the substrate surface. The polystyrene-equivalent number average molecular weight (Mn) of the formed free polymer measured by gel permeation chromatography (GPC) is usually 1,000 to 10,000,000, preferably 100, 000 or more.

According to the production method of the present invention, it is possible to easily produce a surface-modified substrate in which the surface properties of the substrate are significantly modified. Therefore, the production method of the present invention is useful as a method for producing various substrates used in various fields such as medical members, electronic materials, display materials, semiconductor materials, machine parts, sliding members, and battery materials. is. Furthermore, since it has a fluorescent polymer layer that emits fluorescence when irradiated with ultraviolet rays, it can be used for dummy prevention, security applications, design applications, latent image expression, and the like.

<Method for inspecting surface-modified substrate>
The method for inspecting a surface-modified substrate of the present invention uses the fluorescence generated by irradiating the fluorescent polymer layer of the surface-modified substrate manufactured by the above-described manufacturing method with ultraviolet rays to detect the state of the fluorescent polymer layer. It has a process to confirm. By observing the fluorescence emitted from the fluorescent polymer layer, whether the substrate surface was successfully modified; whether the entire substrate surface was modified; whether the surface of all substrates (all lots) was modified ; etc. can be confirmed. That is, the method for inspecting a surface-modified substrate of the present invention is a type of non-destructive inspection capable of inspecting products without damaging them.

As a device for irradiating ultraviolet rays, for example, a light source emitting ultraviolet rays of 254 nm, 350 to 400 nm, etc., a black light, a mercury lamp, a metal halide lamp, an LED light, and the like can be used. In addition, the surface-modified substrates may be individually inspected using a handy type device, or a plurality of surface-modified substrates placed on a conveying means such as a belt conveyor may be mechanically continuously inspected. may Furthermore, a fluorescence microscope can be used to confirm flaws, defects, and the like on the order of μm or less. Spectrophotometers such as spectrofluorophotometers and UV-visible spectrophotometers can also be used.

EXAMPLES The present invention will be specifically described below based on Examples, but the present invention is not limited to these Examples. "Parts" and "%" in Examples and Comparative Examples are based on mass unless otherwise specified.

<Production of surface-modified substrate (1)>
(Reference example 1)
After ultrasonically cleaning a silicon substrate of 1 cm × 1 cm size with isopropyl alcohol, it was irradiated with UV ozone using a chip cleaner (manufactured by Bioforce Nanoscience) to form hydroxyl groups on the surface of the silicon substrate for activation. The activated silicon substrate was immersed in a container containing 100 parts of ethanol, 10 parts of 28% aqueous ammonia solution, and 1 part of 2-bromo-2-methylpropionyloxypropyltrimethoxysilane (BPM) for 12 hours. The removed silicon substrate was dried at 80° C. for 10 minutes using a dryer.

Into a glass sample bottle, 0.0930 parts of copper(I) bromide, 0.6473 parts of dinonyl bipyridine, 20.0240 parts of methyl methacrylate (MMA), the compound represented by the general formula (5) (R = methyl group, 3″-methacryloxyspirobenzo[c]-furan[1,9″]xanthen-3-one, maximum absorption wavelength 341 nm, fluorescent dye-1) 0.1 parts, anisole 20.0 parts, and bromoisobutyric acid 0.01 part of a 1.95% anisole solution of ethyl (EBIB) was added and homogenized to obtain a dark brown polymerization solution.

10 parts of the obtained polymerization solution and the above silicon substrate were placed in a glass Schlenk tube equipped with a three-way cock. After blowing argon gas for 30 minutes, the three-way cock was closed and the tube was sealed to form an ampoule tube. This ampoule tube was placed in a hot water bath at 60° C. and polymerized for 6 hours. After cooling, a part of the polymerization solution in the ampoule tube was sampled, and the polystyrene-equivalent number average molecular weight (Mn) of the polymer measured by GPC using tetrahydrofuran (THF) as a developing solvent was 120,000, and the molecular weight distribution ( Weight average molecular weight (Mw)/number average molecular weight (Mn) = PDI) was 1.05. The silicon substrate taken out from the ampoule tube was immersed in THF for 12 hours to obtain a surface-modified substrate on which a polymer layer exhibiting iridescent interference was formed.

The obtained surface-modified base material was irradiated with ultraviolet rays having a wavelength of 365 nm, and it was confirmed that the polymer layer on the surface emitted light. Moreover, no scratches or defects were found in the polymer layer. From the above, it was confirmed that a polymer layer having no defects in the coating film and the like was formed on the obtained surface-modified base material. The film thickness of the polymer layer measured using ellipsometry (trade name “EC-400”, manufactured by JA Woollam) was 75 nm.

(Comparative example 1)
A surface-modified substrate on which a polymer layer was formed was obtained in the same manner as in Reference Example 1, except that the fluorescent dye-1 was not used. The resulting polymer had an Mn of 165,000 and a PDI of 1.06. Moreover, the film thickness of the formed polymer layer was 78.5 nm. The resulting surface-modified substrate was irradiated with ultraviolet rays having a wavelength of 365 nm, but the polymer layer on the surface did not emit light. Therefore, it was not possible to confirm whether or not the formed polymer layer had defects or the like.

(Example 2)
A silicon substrate and a polymerization solution similar to those used in Reference Example 1 were prepared. After the silicon substrate was placed in a polyethylene sample bottle, the sample bottle was filled with a polymerization solution and capped. It was wrapped with tape so that the polymerization solution would not leak, and was placed in an aluminum pouch and laminated to prevent air from entering. Put an aluminum pouch in a high-pressure device (trade name "PV-400 series", manufactured by Shin Corporation) containing water as a pressurizing medium, heat to 60 ° C., pressurize to 400 MPa and polymerize for 4 hours, A surface-modified substrate having a polymer layer formed on the surface of the silicon substrate was obtained. The resulting polymer had an Mn of 1,500,000 and a PDI of 1.04. Moreover, the film thickness of the formed polymer layer was 750 nm. The obtained surface-modified base material was irradiated with ultraviolet rays having a wavelength of 365 nm, and it was confirmed that the polymer layer on the surface emitted light. Moreover, no scratches or defects were found in the polymer layer.

(Example 3)
A substrate made of silicon carbide (a disk with a diameter of 1 cm and a thickness of 2 mm) was prepared and activated in the same manner as in Reference Example 1 described above. 100 parts of ethanol, 10 parts of a 28% aqueous ammonia solution, and 1 part of 2-iodo-2-methylpropionyloxyhexyltriethoxysilane (IHE) were placed in a container containing the above activated substrate and immersed for 12 hours. After drying, it was taken out and air-dried.

In a glass sample bottle, 0.406 parts of tetrabutylammonium iodide (TBAI), 55.07 parts of MMA, 55.07 parts of 3-methoxy-N,N-dimethylpropionamide (MDMPA), and 1.5 parts of ethyl iodobutyrate were added. 0.1 part of a 95% MDMPA solution, and the compound represented by the general formula (11) (R = methyl group, 9-(2-methacryloyloxyethoxycarbonylphenyl)-3,6-bis(diethylamino)xanthylium bis( Trifluoromethanesulfonyl)imide salt, maximum absorption wavelength 552 nm, fluorescent dye-2) 0.826 parts were added and homogenized to obtain a red transparent polymerization solution.

After the substrate was placed in a fluororesin sample bottle, the sample bottle was filled with a polymerization solution, sealed, placed in an aluminum pouch, and laminated so as to prevent air from entering. An aluminum pouch was placed in a high-pressure apparatus, heated to 85° C., pressurized to 400 MPa and polymerized for 6 hours to obtain a surface-modified substrate having a polymer layer formed on the surface of the silicon carbide substrate. . The resulting polymer had an Mn of 1,240,000 and a PDI of 1.52. Moreover, the film thickness of the formed polymer layer was 620 nm. The polymer had a Mn of 1,270,000 and a PDI of 1.43 as determined by GPC UV absorption detector. The resulting surface-modified substrate was washed with THF and then dried. It was confirmed that the polymer layer on the surface emitted light by irradiating ultraviolet rays of a black light. Moreover, no scratches or defects were found in the polymer layer. The surface-modified substrate was immersed in THF, ultrasonically cleaned, and then dried. It was confirmed that the polymer layer on the surface emitted light by irradiating ultraviolet rays again.

(Example 4)
A surface modified product in which a polymer layer was formed on the surface of a silicon carbide substrate in the same manner as in Example 3 above except that BPM was used instead of IHE and EBIB was used instead of ethyl iodobutyrate. A quality substrate was obtained. The resulting polymer had an Mn of 1,620,000 and a PDI of 2.88. Moreover, the film thickness of the formed polymer layer was 520 nm. The resulting surface-modified substrate was washed with THF and then dried. It was confirmed that the polymer layer on the surface emitted light by irradiating ultraviolet rays of a black light. Moreover, no scratches or defects were found in the polymer layer.

<Synthesis of starting compound>
(Synthesis example 1)
100 parts of propylene glycol monomethyl ether acetate (PGMAc) was placed in a reactor equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen inlet tube, heated to 80° C., and nitrogen gas was blown thereinto. In a separate container, 2-(2-bromoisobutyryloxy)ethyl methacrylate (BBEM) 50 parts, methacryloyloxypropyltriethoxysilyl (MOPS) 50 parts, and azobisisobutyronitrile (AIBN) 1.5 were added and stirred to prepare a uniform monomer mixture. After half the amount of the monomer mixture was added to the reactor, the remainder was added dropwise over 2 hours and then polymerized for 8 hours to obtain a polymer liquid. A portion of the polymer liquid was sampled and measured to have a solid content of 49.2%, confirming that most of the monomers were polymerized. The Mn of the polymer in the polymer liquid was 23,000 and the PDI was 2.51. PGMAc was added to the obtained polymer liquid to dilute it, and a starting group polymer 1 solution having a solid content of 15% was obtained. The initiating group polymer 1 in the initiating group polymer 1 solution is a polymer-type treatment agent having predetermined initiating groups and alkoxysilyl groups.

<Production of surface-modified substrate (2)>
(Example 5)
A glass substrate having a size of 3 cm×3 cm was prepared and activated in the same manner as in Reference Example 1 described above. The starting group polymer 1 solution prepared in Synthesis Example 1 was spin-coated on a glass substrate at 2,000 rpm for 30 seconds, and then cured by baking at 90° C. for 90 seconds and 150° C. for 10 minutes to form a coating film. The coating film thickness measured by ellipsometry was 1.69 μm. Then, a surface-modified base material having a polymer layer formed on the surface of the glass substrate was obtained in the same manner as in Example 4 described above, except that the glass substrate having the coating film formed thereon was used. The resulting polymer had an Mn of 1,420,000 and a PDI of 2.63. The film thickness of the polymer layer including the coating film formed from the starting group polymer 1 solution was 1.97 μm. That is, the film thickness of the polymer layer formed on the coating film was 280 nm. The resulting surface-modified substrate was washed with THF and then dried. It was confirmed that the polymer layer on the surface emitted red light by irradiating ultraviolet rays. Moreover, no scratches or defects were found in the polymer layer.

(Example 6)
Twelve SUS402 metal plates of 1.5 cm×1.5 cm and 2.5 mm thickness were prepared, activated in the same manner as in Reference Example 1, and then surface-treated with BPM. Four sets of fluororesin folders capable of accommodating three metal plates were prepared, and metal plates surface-treated with BPM were set in these folders. A fluororesin sample bottle was loaded with a folder, placed in a glove box, further filled with the polymerization solution prepared in Reference Example 1, sealed, placed in an aluminum pouch, and laminated to prevent air from entering. Put the aluminum pouch in the high-pressure apparatus used in Example 2, heat to 60 ° C., pressurize to 400 MPa and polymerize for 6 hours, 12 surface modifications in which a polymer layer was formed on the surface of the metal plate A substrate was obtained. The resulting polymer had an Mn of 1,080,000 and a PDI of 1.23. Moreover, the film thickness of the formed polymer layer was 630 nm in each case. The resulting surface-modified substrate was washed with THF and then dried. All of the surface-modified substrates looked the same in appearance, confirming that there were no problems. Then, when irradiated with ultraviolet rays, there was one surface-modified substrate on which a polymer layer having a portion (scratches) that did not emit light was formed. This made it possible to determine that one surface-modified substrate (lot) was rejected.

According to the method for producing a surface-modified substrate of the present invention, in addition to parts such as automobiles, aircraft, electronic equipment, home appliances, battery members, medical materials, and display materials, parts in the security field and parts such as display materials It is useful as a method for producing the substrate used.

Claims (4)

Under pressure conditions of 100 to 1,000 MPa, a monomer containing a radically polymerizable fluorescent dye is surface-initiated radical polymerization or surface-initiated living radical polymerization in the presence of a substrate to which a polymerization initiating group is bonded, and the surface of the substrate is coated. The fluorescent polymer layer of the surface-modified substrate produced by the method for producing a surface-modified substrate comprising the step of forming a fluorescent polymer layer having a thickness of 100 nm or more comprising a bonded fluorescent polymer is irradiated with ultraviolet rays. A method for inspecting a surface-modified substrate, comprising the step of confirming the presence or absence and degree of defects in the fluorescent polymer layer using fluorescence generated by the method. The method for inspecting a surface-modified substrate according to claim 1 , wherein the polymerization initiation group is represented by the following general formula (1) or (2).

(In the general formula (1), X represents a chlorine atom, a bromine atom, or an iodine atom, and R ₁ represents a hydrogen atom, an alkyl group, an aryl group, a cyano group, an acyl group, a carboxy group, an ester group, or represents an amide group, R ₂ represents an alkyl group, an aryl group, a cyano group, an acyl group, a carboxy group, an ester group, or an amide group, and "*" represents a bonding position)

(In the general formula (2), X represents a chlorine atom, a bromine atom, or an iodine atom, Y represents O or NH, and R ₃ represents a hydrogen atom, an alkyl group, an aryl group, or an acyl group. shown, R ₄ represents an alkyl group, an aryl group, or an acyl group, and "*" represents the bonding position) The production method further comprises surface-initiated radical polymerization or The method for inspecting a surface-modified substrate according to claim 1 or 2 , wherein the surface-initiated living radical polymerization is performed. The method for inspecting a surface-modified substrate according to any one of claims 1 to 3 , wherein the radically polymerizable fluorescent dye is a monomer having a (meth)acryloyloxy group.