Antimicrobial adhesion inhibitor and method for inhibiting bacterial adhesion

Abstract

To provide a bacteria adhesion inhibitor capable of obtaining good bacteria adhesion inhibiting effect against various bacterial strains and on surfaces of solid bodies made of various materials.SOLUTION: (1) A bacteria adhesion inhibitor contains a polymer that has a hydrophobic group having three or more carbon atoms at a side chain terminal, at least either of a main chain or a side chain has hydrophilicity, and in which the polymer satisfies the following conditions 1 and 2; and (2) a bacteria adhesion inhibiting method includes a treatment step in which the polymer is physically adsorbed onto a surface of a solid body with an aqueous solution containing the polymer that has a hydrophobic group having three or more carbon atoms at a side chain terminal, and at least either of a main chain or a side chain has hydrophilicity, and the polymer satisfies the conditions 1 and 2. The condition 1 is: in a crystal oscillator microbalance method, a frequency variation ΔF and an energy dissipation change ΔD of a 0.1 mass% solution of the polymer in water with a hardness of 4° dH to a polyester-coated crystal oscillator are measured, and a ratio (ΔD / ΔF) obtained by such measurement should be 0.15 or more; and the condition 2 is: in a captive bubble method, an underwater contact angle of a bubble to the polymer to be measured should be 120° or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a bacterial adhesion inhibitor and a method for inhibiting bacterial adhesion. [Background technology]

[0002] Antimicrobial materials are in high demand not only in the medical and hygiene fields, but also in everyday household goods. Antimicrobial materials include antibacterial agents and disinfectants that suppress the growth of bacteria on solid surfaces, as well as antimicrobial adhesion inhibitors that prevent bacteria from adhering to solid surfaces.

[0003] For example, Patent Document 1 describes an antimicrobial material made of a superhydrophilic material having a contact angle with water of 0 to 1 degree, with the aim of providing an antimicrobial material that prevents microorganisms from adhering to the surface of a material. The superhydrophilic material described is a copolymer of 2-methacryloyloxyethyl phosphorylcholine and butyl methacrylate. Patent Document 2 describes an oral microbial adhesion inhibitor that provides a sustained microbial adhesion inhibitory effect, and includes a phosphorylcholine group-containing polymer, a water-soluble polysaccharide, and a poly(meth)acrylic acid derivative. The phosphorylcholine group-containing polymer described is a copolymer of 2-methacryloyloxyethyl phosphorylcholine and butyl methacrylate. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2003-180801 [Patent Document 2] Japanese Patent Publication No. 2011-153101 [Overview of the project] [Problems that the invention aims to solve]

[0005] Once bacteria attach to a solid surface, they multiply and form a biofilm. Removing bacteria and biofilms attached to solid surfaces is time-consuming and costly, so there is a growing demand for bacterial adhesion inhibitors and methods that can prevent bacteria from attaching to solid surfaces. However, even with hydrophilic polymers, sufficient inhibitory effects on bacterial adhesion were not always obtained depending on the bacterial species. Therefore, it was necessary to verify and select the type of hydrophilic polymer that would provide a good inhibitory effect on bacterial adhesion depending on the target bacterial species to be inhibited. Furthermore, there is a need for antimicrobial adhesion inhibitors and methods that can achieve good antimicrobial adhesion inhibition effects on the surfaces of solids of various materials.

[0006] The present invention relates to a bacterial adhesion inhibitor and a bacterial adhesion inhibitor that can obtain a good bacterial adhesion inhibitory effect against various bacterial species and on the surface of various solid materials. [Means for solving the problem]

[0007] The inventors have determined the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] for a hydrophilic polymer using the quartz crystal microbalancing (hereinafter sometimes abbreviated as "QCM") method. -6 We found that the ratio of ΔD to ΔF (ΔD / ΔF) and the water contact angle, obtained by measuring [the temperature], correlate with the antimicrobial adhesion effect. Based on this, we focused on the fact that a good antimicrobial adhesion effect can be achieved against various bacterial species and on the surfaces of various solid materials, and found that the above problem can be solved.

[0008] In other words, the present invention relates to the following [1] and [2]. [1] A bacterial adhesion inhibitor comprising a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chain, and at least one of the main chain and side chain being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the quartz crystal microbalance method, the amount of frequency change ΔF [Hz] and the amount of change in energy dissipation ΔD [×10 -6 of a 0.1% by mass solution of the polymer in water with a hardness of 4° dH with respect to a quartz crystal coated with polyester are measured, and the ratio (ΔD / ΔF) of ΔD to ΔF is 0.15 or more Condition 2: The contact angle of the bubble with respect to the polymer measured by the captive bubble method in water is 120° or more [2] A method for suppressing bacterial adhesion, comprising a step of performing a treatment of physically adsorbing the polymer on the surface of a solid with an aqueous solution containing a polymer having a hydrophobic group having 3 or more carbon atoms at the side chain terminal and having hydrophilicity in at least one of the main chain and the side chain, and the polymer satisfies the following Conditions 1 and 2 Condition 1: By the quartz crystal microbalance method, the amount of frequency change ΔF [Hz] and the amount of change in energy dissipation ΔD [×10 -6 of a 0.1% by mass solution of the polymer in water with a hardness of 4° dH with respect to a quartz crystal coated with polyester are measured, and the ratio (ΔD / ΔF) of ΔD to ΔF is 0.15 or more Condition 2: The contact angle of the bubble with respect to the polymer measured by the captive bubble method in water is 120° or more [Advantages of the Invention

[0009] According to the present invention, it is possible to provide a bacterial adhesion inhibitor and a method for suppressing bacterial adhesion, which can obtain a good effect of suppressing bacterial adhesion against various bacterial species and on the surfaces of solids of various materials Further, according to the present invention, it is possible to provide a method for screening a bacterial adhesion inhibitor that can obtain a good effect of suppressing bacterial adhesion [Modes for Carrying Out the Invention

[0010] [Bacterial Adhesion Inhibitor The bacterial adhesion inhibitor of the present invention contains a polymer having a hydrophobic group having 3 or more carbon atoms at the side chain terminal and having hydrophilicity in at least one of the main chain and the side chain, and the polymer satisfies the following Conditions 1 and 2 Condition 1: By the quartz crystal microbalance method, the frequency change amount ΔF [Hz] and the energy dissipation change ΔD [×10 -6 of the 0.1 mass% solution of the polymer in water with a hardness of 4° dH with respect to the polyester-coated quartz crystal resonator are measured, and the ratio (ΔD / ΔF) of ΔD to ΔF is 0.15 or more Condition 2: The underwater contact angle of bubbles with respect to the polymer measured by the captive bubble method is 120° or more

[0011] The bacterial adhesion inhibitor of the present invention contains a predetermined polymer that satisfies the above Conditions 1 and 2, and thus exhibits a good bacterial adhesion inhibitory effect against various bacterial species and on the surfaces of solids of various materials.

[0012] From the viewpoints of the stability of the bacterial adhesion inhibitor and the ease of handling during application, etc., the bacterial adhesion inhibitor may contain components other than the polymer, and examples of the components include water, surfactants, organic solvents, fragrances, pH adjusters, etc.

[0013] <Condition 1> Condition 1 that the polymer in the bacterial adhesion inhibitor of the present invention should satisfy is that by the QCM method, the frequency change amount ΔF [Hz] and the energy dissipation change ΔD [×10 -6 of the 0.1 mass% solution of the polymer in water with a hardness of 4° dH with respect to the polyester-coated quartz crystal resonator are measured, and the ratio (ΔD / ΔF) of ΔD to ΔF is 0.15 or more.

[0014] In the QCM method, the resonance frequency of the sensor by the quartz crystal resonator is measured, and the frequency change amount ΔF [Hz] is obtained. In the present invention, furthermore, the energy dissipation when the resonance is stopped is also measured together, and the ratio (ΔD / ΔF) of the energy dissipation change ΔD [×10 -6 to the frequency change amount ΔF [Hz] is obtained. Thus, the method of measuring both the frequency change and the energy dissipation as the measurement of the intermolecular interaction by the QCM method is also called the QCM-D method or QCM-D measurement.

[0015] Under Condition 1, the energy dissipation change ΔD[×10] is determined by performing a QCM-D measurement of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz oscillator. -6 The ratio (ΔD / ΔF) of the value The ratio (ΔD / ΔF) calculated here can be considered an indicator that combines the amount of polymer adsorbed onto the polyester surface coated on the quartz crystal oscillator and the softness of the adsorbed polymer. A larger value of ΔF indicates a greater amount of polymer adsorbed onto the polyester surface, and a larger value of ΔD indicates a softer polymer adsorption surface. Therefore, a larger ratio (ΔD / ΔF) indicates a softer film formed by the polymer adsorbed onto the polyester surface, and it is presumed that this soft surface condition on the surfaces of various solid materials is one of the factors that suppresses bacterial adhesion.

[0016] A ratio (ΔD / ΔF) of 0.15 or higher, preferably 0.16 or higher, allows the polymer to exhibit a good antimicrobial adhesion effect. Furthermore, while there is no particular upper limit to the ratio (ΔD / ΔF), in practice, it is preferably 0.50 or lower, more preferably 0.45 or lower, and even more preferably 0.40 or lower.

[0017] ΔD[×10 -6 From the viewpoint of making the polymer adsorption surface appropriately soft and obtaining a good antimicrobial adhesion inhibitory effect, the value is preferably 2 or more, more preferably 3 or more, even more preferably 4 or more, even more preferably 6 or more, even more preferably 8 or more, even more preferably 10 or more, even more preferably 12 or more, even more preferably 14 or more, and preferably 60 or less, more preferably 55 or less, even more preferably 50 or less.

[0018] ΔF[Hz] is preferably 10 or more, more preferably 20 or more, even more preferably 30 or more, even more preferably 40 or more, even more preferably 50 or more, even more preferably 60 or more, even more preferably 70 or more, even more preferably 80 or more, and preferably 150 or less, more preferably 140 or less, and even more preferably 130 or less, from the viewpoint of ensuring an appropriate amount of polymer adsorption to the polyester surface in the QCM method and obtaining a good antimicrobial adhesion inhibitory effect.

[0019] In the QCM-D measurement under Condition 1, since polyester fibers are assumed to be the material of the solid to which the bacterial adhesion inhibitor is applied, a quartz crystal oscillator coated with polyester is used as the standard. For coating the quartz crystal oscillator, a polyester synthesized by polycondensation of, for example, 32 moles of bisphenol A propylene oxide (2.2) adduct, 21 moles of bisphenol A propylene oxide (3.0) adduct, 33 moles of fumaric acid, and 14 moles of trimellitic anhydride is used, from the viewpoint of achieving a smooth coating. Such polyesters are preferred because they readily form a smooth polyester coating surface suitable for QCM-D measurement when dissolved in chloroform and spin-coated. Specifically, it is preferable to coat with the polyester T described in the examples using the method described in the examples. Furthermore, for the QCM-D measurement under Condition 1, water with a hardness of 4°dH is used, assuming standard Japanese tap water.

[0020] <Condition 2> Condition 2 that the polymer in the bacterial adhesion inhibitor of the present invention must satisfy is that the underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or more.

[0021] The captive bubble method is a method for measuring the contact angle of air bubbles with respect to a solid surface in water, and is also called the underwater bubble method. The underwater contact angle measured by this method can be suitably used as an indicator of the hydrophilicity of a highly hydrophilic solid surface. Specifically, the underwater contact angle can be measured by the method described in the examples. A larger contact angle in water indicates higher hydrophilicity of the polymer.

[0022] The polymer can exhibit a good antimicrobial adhesion inhibitory effect if the water contact angle is 120° or higher, preferably 130° or higher, more preferably 140° or higher, and even more preferably 142° or higher. Furthermore, the upper limit of the water contact angle is not particularly limited, but in practice, it is preferably 160° or lower, more preferably 155° or lower, and even more preferably 150° or lower.

[0023] <polymer> The polymer used in the bacterial adhesion inhibitor of the present invention has a hydrophobic group with 3 or more carbon atoms at the end of its side chain, and at least one of the main chain and side chains is hydrophilic, from the viewpoint of adsorption to various solid surfaces to which the bacterial adhesion inhibitor is applied, and the hydrophilicity of the polymer in water in which bacteria are present. The polymer is preferably water-soluble from the viewpoint of good bacterial adhesion inhibitory effect and ease of handling. Herein, "water-soluble" in this specification means that the solubility in water at 25°C is 0.1 g / 100 g or more.

[0024] The hydrophobic group at the side chain end of the polymer is a group that does not readily mix with water and is also called a lipophilic group. The hydrophobic group is preferably one or more functional groups selected from the group consisting of hydrocarbyl groups, fluoroalkyl groups, and silicone groups, and is more preferably a hydrocarbyl group from the viewpoint of balancing adsorption to solid surfaces and hydrophilicity, as well as ease of synthesis. Examples of the hydrocarbyl group include alkyl groups; aryl groups such as phenyl, orthotril, metatril, paratril, naphthyl, anthryl, phenanthryl, and biphenyl groups; aralkyl groups such as benzyl and phenethyl groups; alkenyl groups; and alkynyl groups. Of these, the hydrocarbyl group is more preferably one or more selected from the group consisting of linear or branched alkyl groups, phenyl, orthotril, metatril, paratril, biphenyl, and benzyl groups, from the viewpoint of good bacterial adhesion inhibition effect. Furthermore, from the viewpoint of good bacterial adhesion inhibition effect, availability, and economic efficiency, the hydrocarbyl group is more preferably a linear or branched alkyl group, and even more preferably a branched alkyl group. The number of carbon atoms in the hydrocarbyl group is preferably 3 or more, more preferably 4 or more, more preferably 5 or more, and even more preferably 6 or more, from the viewpoint of a good antimicrobial adhesion inhibitory effect. Furthermore, from the viewpoint of balancing adsorption to solid surfaces and hydrophilicity, it is preferably 20 or less, more preferably 18 or less, and even more preferably 16 or less. Taking all of these viewpoints into account, the number of carbon atoms in the hydrocarbyl group is preferably 3 to 20, more preferably 4 to 18, even more preferably 5 to 16, and even more preferably 6 to 16, from the viewpoint of a good antimicrobial adhesion inhibitory effect. Therefore, the hydrophobic group is more preferably one or more selected from the group consisting of linear or branched alkyl groups having 3 to 20 carbon atoms, phenyl groups, orthotolyl groups, metatolyl groups, paratolyl groups, biphenyl groups, and benzyl groups. Furthermore, from the viewpoint of good bacterial adhesion inhibitory effect, as well as availability and economic efficiency, the hydrophobic group is more preferably a linear or branched alkyl group having 3 to 20 carbon atoms, more preferably a branched alkyl group having 3 to 20 carbon atoms, more preferably a branched alkyl group having 4 to 18 carbon atoms, and more preferably a branched alkyl group having 5 to 16 carbon atoms.

[0025] The polymer is hydrophilic because at least one of its main chain and side chains has a hydrophilic group, and preferably because it is composed of a polysaccharide or a polysaccharide derivative. The hydrophilic group is a group that readily mixes with water and can form weak hydrogen bonds, ionic bonds, etc., with water. The hydrophilic group may be a single type or two or more types. The hydrophilic group is preferably one or more functional groups selected from the group consisting of anionic groups, cationic groups, betaine groups, oxyalkylene groups, hydroxyl groups, amide groups, carboxyl groups, amino groups, and ester groups; more preferably, one or more functional groups selected from the group consisting of anionic groups, betaine groups, oxyalkylene groups, and hydroxyl groups; and even more preferably, one or more functional groups selected from the group consisting of phosphobetaine groups, sulfobetaine groups, oxyethylene groups, and hydroxyl groups.

[0026] From the viewpoint of a good antimicrobial adhesion inhibitory effect, the molar ratio of hydrophilic groups to hydrophobic groups in the polymer is preferably 20 / 80 or more, more preferably 30 / 70 or more, even more preferably 40 / 60 or more, and even more preferably 50 / 50 or more, and preferably 99.9 / 0.1 or less, more preferably 99.5 / 0.5 or less, even more preferably 99.3 / 0.7 or less, and even more preferably 99.0 / 1.0 or less. Taking all of these viewpoints into account, from the viewpoint of a good antimicrobial adhesion inhibitory effect, the molar ratio of hydrophilic groups to hydrophobic groups in the polymer is preferably 20 / 80 or more and 99.9 / 0.1 or less, more preferably 30 / 70 or more and 99.5 / 0.5 or less, even more preferably 40 / 60 or more and 99.3 / 0.7 or less, and even more preferably 50 / 50 or more and 99.0 / 1.0 or less.

[0027] As for the polymer, from the viewpoint of a good antimicrobial adhesion effect, it is preferable that the main chain is composed of a polysaccharide or a polysaccharide derivative, and it is preferable that the main chain is composed of a polysaccharide derivative. Examples of polysaccharides include cellulose, guar gum, and starch, with cellulose or guar gum being preferred, and cellulose being more preferred. Examples of polysaccharide derivatives include cellulose derivatives, guar gum derivatives, and starch derivatives, with cellulose derivatives or guar gum derivatives being preferred, and cellulose derivatives being more preferred. Examples of polysaccharide derivatives include hydroxyalkylated polysaccharides obtained by hydroxyalkylating the aforementioned polysaccharides. Specific examples of hydroxyalkylated polysaccharides include hydroxyethylcellulose, hydroxyethyl guar gum, hydroxyethyl starch, hydroxypropylcellulose, hydroxypropyl guar gum, hydroxypropyl starch, hydroxyethyl methylcellulose, hydroxyethyl methyl guar gum, hydroxyethyl methyl starch, hydroxypropyl methylcellulose, hydroxypropyl methyl guar gum, and hydroxypropyl methyl starch. Of these, the polysaccharide derivative is preferably one or more selected from the group consisting of hydroxyethylcellulose (hereinafter sometimes abbreviated as "HEC") and hydroxypropylcellulose (hereinafter sometimes abbreviated as "HPC"), and more preferably hydroxyethylcellulose (HEC).

[0028] Furthermore, from the viewpoint of a good antimicrobial adhesion inhibitory effect, the polymer is preferably one that has a betaine group in its side chain. The betaine group is preferably a sulfobetaine group, a carbobetaine group, or a phosphobetaine group, and more preferably a sulfobetaine group. From the viewpoint of having a good antimicrobial adhesion inhibitory effect, polymers having a sulfobetaine group and alkyl (meth)acrylate are preferred. In this specification, "(meth)acrylic acid" means acrylic acid or methacrylic acid.

[0029] Examples of monomers having a sulfobetaine group include N-(3-sulfopropyl)-N-(meth)acryloyloxyethyl-N,N-dimethylammonium betaine ([2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide) and N-(3-sulfopropyl)-N-(meth)acryloylamidopropyl-N,N-dimethylammonium betaine. The monomer having a sulfobetaine group may be a single type or two or more types.

[0030] Examples of (meth)acrylic acid esters include (meth)acrylic acid esters having linear or branched alkyl groups such as propyl (meth)acrylate, n-butyl (meth)acrylate, iso-butyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-decyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, palmityl (meth)acrylate, and stearyl (meth)acrylate; (meth)acrylic acid esters having alicyclic alkyl groups such as cyclohexyl (meth)acrylate; and (meth)acrylic acid esters having hydrocarbon groups with 3 to 20 carbon atoms such as benzyl (meth)acrylate. The (meth)acrylic acid ester may be a single type or two or more types.

[0031] Preferred specific examples of the polymer include, for example, alkyl glycidyl ether-modified hydroxyethyl cellulose, alkyl glycidyl ether-modified hydroxyethyl cellulose, and [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / alkyl methacrylate copolymer. Specific examples of the [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / alkyl methacrylate copolymer include [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate copolymer (for example, monomer composition ratio (molar ratio) 60 / 40).

[0032] The preferred weight-average molecular weight of the polymer varies depending on the type of polymer, but from the viewpoint of ease of handling of the bacterial adhesion inhibitor and exhibiting a good bacterial adhesion inhibitory effect, it is in an approximate range of preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, and still more preferably 50,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, and even more preferably 350,000 or less. When the main chain of the polymer is composed of a polysaccharide or a polysaccharide derivative, the weight-average molecular weight is, from the viewpoint of ease of handling of the bacterial adhesion inhibitor and exhibiting a good bacterial adhesion inhibitory effect, preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, even more preferably 50,000 or more, even more preferably 100,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, and even more preferably 350,000 or less. If the main chain of the polymer is composed of a polysaccharide or a polysaccharide derivative, the weight-average molecular weight can be measured by gel permeation chromatography (GPC) in the same manner as the measurement of the weight-average molecular weight of lauryl glycidyl ether-modified HEC described in the examples. Furthermore, if the polymer is one or more modified hydroxyalkylcelluloses selected from the group consisting of alkyl glycidyl ether-modified hydroxyethylcellulose and alkyl glycidyl ether-modified hydroxypropylcellulose, and the increase in molecular weight due to the modification of the polymer does not affect the overall molecular weight of the polymer, the weight-average molecular weight of the polymer can be considered to be the same as the weight-average molecular weight of the raw material hydroxyalkylcellulose. When the main chain of the polymer is composed of a copolymer of a monomer having a sulfobetaine group and an alkyl (meth)acrylate, the weight-average molecular weight is, from the viewpoint of ease of handling of the bacterial adhesion inhibitor and exhibiting a good bacterial adhesion inhibitory effect, preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, and even more preferably 50,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, even more preferably 300,000 or less, even more preferably 200,000 or less, even more preferably 150,000 or less, and even more preferably 100,000 or less. If the main chain of the polymer is composed of a copolymer of a monomer having a sulfobetaine group and an alkyl (meth)acrylate, the weight-average molecular weight can be measured by static light scattering (SLS) in the same manner as the measurement of the [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate (molar ratio 60 / 40) copolymer described in the examples.

[0033] <Target bacterial species> The bacterial adhesion inhibitor of the present invention exhibits a good bacterial adhesion inhibitory effect not only against a specific type of bacteria, but also against various other types of bacteria. In the present invention, the fungal species targeted for adhesion inhibition include, for example, fungi such as Rhodotorula mucilaginosa, Saccharomyces, and Pichia; molds such as Cladosporium, Aspergillus, Candida parapsilosis, Penicillium, Alternaria, Phoma, and Aureobasidium; and Pseudomonas aeruginosa and Pseudomonas putida. Pseudomonas (e.g., putida), Moraxella (e.g., Moraxella osloensis), Ralstonia, Burkholderia, Escherichia (e.g., Escherichia coli), Cupriavidus, Cyclobacter, Alcaligenes, Klebsiella, Proteus, Serratia, Roseomonas (e.g., Roseomonas mucosa), Methylobacterium variabile Gram-negative bacteria, such as those belonging to the genera Methylobacterium (including variabile), Acinetobacter, and Sphingomonas;Gram-positive bacteria represented by the genus Bacillus such as Bacillus cereus and Bacillus coagulans, the genus Lactobacillus, the genus Micrococcus, and the genus Staphylococcus such as Staphylococcus aureus can be mentioned. Against these bacterial species, the bacterial adhesion inhibitor of the present invention shows a good bacterial adhesion inhibitory effect. Among these, the bacterial species to be the target of adhesion inhibition are preferably at least one bacterium selected from the group consisting of Rhodotorula mucilaginosa, Candida parapsilosis, and Roseomonas mucosa from the viewpoint of a good bacterial adhesion inhibitory effect.;

[0034] [Biofilm formation inhibitor] The biofilm formation inhibitor of the present invention contains a polymer having a hydrophobic group with 3 or more carbon atoms at the side chain terminal and having hydrophilicity in at least either the main chain or the side chain, and the polymer satisfies the following conditions 1 and 2. Condition 1: By the quartz crystal microbalance method, the frequency change amount ΔF [Hz] and the energy dissipation change ΔD [×10 -6 of a 0.1 mass% solution of the polymer in water with a hardness of 4° dH with respect to a quartz crystal coated with polyester are measured, and the ratio (ΔD / ΔF) of ΔD to ΔF is 0.15 or more Condition 2: The contact angle of bubbles in water with respect to the polymer measured by the captive bubble method is 120° or more

[0035] A biofilm is a membrane structure formed by bacteria adhering to a solid surface and extracellular polysaccharides produced by the bacteria. Since the formation of a biofilm is premised on the adhesion of bacteria to a solid surface, if the adhesion of bacteria to the solid surface is suppressed, the initial number of bacteria present on the solid surface is reduced, and the formation of the biofilm is suppressed. The composition of the biofilm formation inhibitor of the present invention is the same as that of the bacterial adhesion inhibitor described above. Therefore, the explanation of conditions 1 and 2, the polymer, and the target bacterial species is the same as the explanation in the section on bacterial adhesion inhibitors described above and will be omitted.

[0036] [Antibacterial agent] In the present invention, the antibacterial agent may include a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chain, and at least one of the main chain and side chains being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the quartz crystal microbalancing method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.15 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

[0037] Antibacterial properties mean inhibiting bacterial growth. Since bacterial growth on solid surfaces depends on bacteria adhering to the surface, inhibiting bacterial adhesion reduces the initial number of bacteria present on the surface, thereby suppressing bacterial growth. The composition of the antibacterial agent is the same as that of the bacterial adhesion inhibitor. Therefore, the explanations of conditions 1 and 2, the polymer, and the target bacterial species are the same as those explained in the section on bacterial adhesion inhibitors above and are therefore omitted.

[0038] [Method for suppressing bacterial adhesion] The present invention provides a method for inhibiting bacterial adhesion, which includes the step of physically adsorbing a polymer onto a solid surface using an aqueous solution containing a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chains, and at least one of the main chain and side chains being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the QCM method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz oscillator. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.15 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

[0039] The present invention provides a method for inhibiting bacterial adhesion by physically adsorbing a predetermined polymer onto the surface of a solid using an aqueous solution containing the polymer that satisfies the above conditions 1 and 2. This method exhibits a good bacterial adhesion inhibitory effect against various bacterial species and on the surfaces of solids of various materials. A good bacterial adhesion inhibitory effect can be obtained whether the solid surface is in the air or in water, and preferably, a better effect can be obtained when the solid surface is in water.

[0040] The aqueous solution containing the polymer (hereinafter referred to as the "polymer aqueous solution") may contain components other than the polymer, from the viewpoint of ease of handling during processing, etc. Examples of such components include surfactants, organic solvents, fragrances, pH adjusters, etc. The organic solvent is preferably a water-soluble organic solvent that can be miscible with water in any proportion.

[0041] <Solid> The present invention provides a method for inhibiting bacterial adhesion, which is applied to the surface of a solid. The solid to be treated may be organic, inorganic, or a composite material, and examples include resins, metals, ceramics, glass, textiles, paper, and the like. The solid material is preferably one or more selected from the group consisting of polyester, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, polytetrafluoroethylene, polyethylene, polypropylene, stainless steel, and glass, as a material that provides a good antimicrobial adhesion effect. More preferably, it is one or more selected from the group consisting of polyethylene terephthalate, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, and stainless steel.

[0042] <polymer> The polymer used in the bacterial adhesion inhibition method of the present invention is the same as the polymer in the bacterial adhesion inhibitor. That is, the polymer has a hydrophobic group with 3 or more carbon atoms at the end of its side chain, and at least one of the main chain and side chains is hydrophilic, satisfying conditions 1 and 2.

[0043] <Polymer aqueous solution> In the bacterial adhesion suppression method of the present invention, the polymer is physically adsorbed onto the surface of the solid to be treated using the polymer aqueous solution. The term "physical adsorption" as used in the present invention is distinguished from chemiadsorption, which is adsorption onto the solid surface accompanied by a chemical reaction. The process of physically adsorbing a polymer onto a solid surface does not require the use of a binder or the polymer as an organic solvent solution. Instead, a good inhibitory effect on bacterial adhesion can be obtained simply and safely by using only an aqueous polymer solution.

[0044] The surface of a solid can be treated with an aqueous polymer solution by methods such as immersion, coating, spraying, or casting. Of these methods, the treatment is preferably carried out by immersing the surface of the solid in an aqueous polysaccharide solution, from the viewpoint of easily treating the solid surface uniformly. Afterwards, if necessary, the surface of the solid may be rinsed with water and dried. The concentration of the polymer in the polymer aqueous solution depends on the treatment method and the desired degree of inhibition of bacterial adhesion, but is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, even more preferably 0.05% by mass or more, and preferably 5% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less. For example, when treating the surface of a solid by immersing it in an aqueous polymer solution, it is preferable to clean the surface of the solid by washing or the like, immerse it in an aqueous solution with a polymer concentration of 0.01% by mass or more and 5% by mass or less for 0.1 hours or more and 24 hours or less, then rinse it with water and air dry or blow dry it.

[0045] [Methods for inhibiting biofilm formation] The present invention provides a method for inhibiting biofilm formation, which includes a step of physically adsorbing a polymer onto a solid surface using an aqueous solution containing a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chains, and at least one of the main chain and side chains being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the QCM method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz oscillator. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.15 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

[0046] Since biofilm formation presupposes the attachment of bacteria to a solid surface, suppressing bacterial attachment to the solid surface reduces the initial number of bacteria present on the solid surface, thereby suppressing biofilm formation. For this reason, the embodiments of the biofilm formation suppression method of the present invention are the same as the bacterial attachment suppression method described above, and therefore, a detailed explanation is omitted.

[0047] [Antibacterial method] The present invention may also be an antibacterial method that includes a step of physically adsorbing a polymer onto a solid surface with an aqueous solution containing a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chains and at least one of the main chain and side chains being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the QCM method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz oscillator. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.15 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

[0048] Since antibacterial action is based on the premise of bacterial adhesion to a solid surface, suppressing bacterial adhesion to the solid surface reduces the initial number of bacteria present on the solid surface, thereby inhibiting bacterial growth. For this reason, the embodiment of the antibacterial method is the same as the bacterial adhesion suppression method, and therefore, a detailed explanation is omitted.

[0049] [Screening method for bacterial adhesion inhibitors] The present invention also provides a screening method for bacterial adhesion inhibitors. The screening method for bacterial adhesion inhibitors of the present invention is a screening method for bacterial adhesion inhibitors containing polymers, and uses the following conditions 1' and 2 as indicators. Condition 1': By the QCM method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz oscillator. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.06 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

[0050] According to the screening method for bacterial adhesion inhibitors of the present invention, by using the above conditions 1' and 2 as indicators, it is possible to screen for bacterial adhesion inhibitors that exhibit good bacterial adhesion inhibitory effects against various bacterial species and on the surfaces of solids of various materials. In particular, it is possible to screen for bacterial adhesion inhibitors that exhibit even better bacterial adhesion inhibitory effects when the solid surface is submerged in water. The target bacterial species are the same as the target bacterial species for the bacterial adhesion inhibitors described above, and the target solid is the same as the solid in the bacterial adhesion inhibition method described above.

[0051] <Condition 1'> The condition 1' that the polymer must satisfy in the screening method for the bacterial adhesion inhibitor of the present invention is the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz oscillator, as determined by the QCM method. -6 The ratio of ΔD to ΔF (ΔD / ΔF), obtained by measuring [the value of ΔD], must be 0.06 or greater. The explanation of the QCM method is the same as the explanation in the section on bacterial adhesion inhibitors above, so it will be omitted here.

[0052] In the screening method for the bacterial adhesion inhibitor of the present invention, the polymer can exhibit a good bacterial adhesion inhibitory effect when the ratio (ΔD / ΔF) is 0.06 or higher, preferably 0.10 or higher, more preferably 0.15 or higher, and even more preferably 0.16 or higher. Furthermore, the upper limit of the ratio (ΔD / ΔF) is not particularly limited, but in practice, it is preferably 0.50 or lower, more preferably 0.45 or lower, and even more preferably 0.40 or lower.

[0053] In the screening method for bacterial adhesion inhibitors of the present invention, ΔD[×10 -6From the viewpoint of making the polymer adsorption surface appropriately soft and obtaining a good antimicrobial adhesion inhibitory effect, the value is preferably 2 or more, more preferably 3 or more, even more preferably 4 or more, even more preferably 6 or more, even more preferably 8 or more, even more preferably 10 or more, even more preferably 12 or more, even more preferably 14 or more, and preferably 60 or less, more preferably 55 or less, even more preferably 50 or less.

[0054] In the screening method for the bacterial adhesion inhibitor of the present invention, ΔF [Hz] is preferably 10 or more, more preferably 20 or more, even more preferably 30 or more, even more preferably 40 or more, even more preferably 50 or more, even more preferably 60 or more, even more preferably 70 or more, even more preferably 80 or more, and preferably 150 or less, more preferably 140 or less, and even more preferably 130 or less, from the viewpoint of ensuring an appropriate amount of polymer adsorption to the polyester surface in the QCM method and obtaining a good bacterial adhesion inhibitory effect.

[0055] <Condition 2> Condition 2, which is an indicator for the screening method of the bacterial adhesion inhibitor of the present invention, is the same as Condition 2 for the bacterial adhesion inhibitor described above.

[0056] [Screening method for biofilm formation inhibitors] The present invention also provides a screening method for biofilm formation inhibitors. The screening method for biofilm formation inhibitors of the present invention is a screening method for biofilm formation inhibitors containing polymers, and uses the following conditions 1' and 2 as indicators. Condition 1': By the QCM method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz oscillator. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.06 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

[0057] According to the biofilm formation inhibitor screening method of the present invention, by using the above conditions 1' and 2 as indicators, it is possible to screen for biofilm formation inhibitors that exhibit a good biofilm formation inhibitory effect against various bacterial species and on the surfaces of solids of various materials. In particular, it is possible to screen for biofilm formation inhibitors that exhibit a better biofilm formation inhibitory effect when the solid surface is submerged in water. The target bacterial species are the same as the target bacterial species for the bacterial adhesion inhibitor, and the target solid is the same as the solid in the bacterial adhesion inhibition method. Condition 1', which is an indicator for the screening method of the bacterial adhesion inhibitor of the present invention, is the same as Condition 1' for the screening method of the bacterial adhesion inhibitor. Furthermore, Condition 2, which is an indicator for the screening method of the biofilm formation inhibitor of the present invention, is the same as Condition 2 for the bacterial adhesion inhibitor.

[0058] [Screening methods for antibacterial agents] The present invention also provides a method for screening antimicrobial agents. The antimicrobial agent screening method is a method for screening antimicrobial agents containing polymers, and uses the following conditions 1' and 2 as indicators. Condition 1': By the QCM method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz oscillator. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.06 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

[0059] According to the above-described screening method for antimicrobial agents, by using conditions 1' and 2 as indicators, it is possible to screen for antimicrobial agents that exhibit good antimicrobial effects against various bacterial species and on the surfaces of solids of various materials. In particular, it is possible to screen for antimicrobial agents that exhibit better antimicrobial effects when the solid surface is submerged in water. The target bacterial species are the same as those for the bacterial adhesion inhibitor, and the target solid is the same as the solid in the bacterial adhesion inhibition method. Condition 1', which is an indicator for the screening method of the antibacterial agent of the present invention, is the same as Condition 1' for the screening method of the bacterial adhesion inhibitor. Furthermore, Condition 2, which is an indicator for the screening method of the antibacterial agent, is the same as Condition 2 for the bacterial adhesion inhibitor.

[0060] With regard to the embodiments described above, the present invention further discloses the following embodiments. <1> A bacterial adhesion inhibitor comprising a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chain, and at least one of the main chain and side chains being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the quartz crystal microbalancing method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.15 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater. <2> A biofilm formation inhibitor comprising a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chain, and at least one of the main chain and side chains being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the quartz crystal microbalancing method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal. -6The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.15 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater. <3> The hydrophobic group of the polymer is preferably one or more functional groups selected from the group consisting of hydrocarbyl groups, fluoroalkyl groups, and silicone groups, and more preferably a hydrocarbyl group. <1> or <2> The agent described above. <4> The hydrocarbyl group is preferably one or more selected from the group consisting of a linear or branched alkyl group, a phenyl group, an orthotril group, a metatril group, a paratril group, a biphenyl group, and a benzyl group. <3> The agent described above. <5> The number of carbon atoms in the hydrocarbyl group is preferably 3 to 20, more preferably 4 to 18, even more preferably 5 to 16, and even more preferably 6 to 16. <3> or <4> The agent described above. <6> The polymer has a hydrophilic group in at least one of its main chain and side chains, wherein the hydrophilic group is preferably one or more functional groups selected from the group consisting of anionic groups, cationic groups, betaine groups, oxyalkylene groups, hydroxyl groups, amide groups, carboxyl groups, amino groups, and ester groups; more preferably one or more functional groups selected from the group consisting of anionic groups, betaine groups, oxyalkylene groups, and hydroxyl groups; and even more preferably one or more functional groups selected from the group consisting of phosphobetaine groups, sulfobetaine groups, oxyethylene groups, and hydroxyl groups. <1> ~ <5> The agent described in any one of the items. <7> The polymer has hydrophilic groups in at least one of its main chain and side chains, and the ratio (molar ratio) of hydrophilic groups to hydrophobic groups in the polymer is preferably 20 / 80 or more and 99.9 / 0.1 or less, more preferably 30 / 70 or more and 99.5 / 0.5 or less, even more preferably 40 / 60 or more and 99.3 / 0.7 or less, and even more preferably 50 / 50 or more and 99.0 / 1.0 or less. <1> ~ <6> The agent described in any one of the items. <8> The main chain of the polymer is composed of a polysaccharide or a polysaccharide derivative. <1> ~ <7> The agent described in any one of the items. <9> The polysaccharide is preferably cellulose or guar gum, more preferably cellulose. <8> The agent described above. <10> The polysaccharide derivative is preferably one or more selected from the group consisting of cellulose derivatives or guar gum derivatives, more preferably cellulose derivatives, even more preferably hydroxyethylcellulose and hydroxypropylcellulose, and even more preferably hydroxyethylcellulose. <8> or <9> The agent described above. <11> The main chain of the polymer is composed of a cellulose derivative. <1> ~ <10> The agent described in any one of the items. <12> The polymer has a betaine group in its side chain. <1> ~ <11> The agent described in any one of the items. <13> The betaine group is preferably a sulfobetaine group, a carbobetaine group, or a phosphobetaine group, more preferably a sulfobetaine group. <12> The agent described above. <14> The polymer is preferably a copolymer of a monomer having a sulfobetaine group and an alkyl (meth)acrylate, more preferably a [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / alkyl methacrylate copolymer, and even more preferably a [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / alkyl methacrylate copolymer having a hydrocarbon group with 3 to 20 carbon atoms. <1> ~ <13> The agent described in any one of the items. <15> The weight-average molecular weight of the polymer is preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, and even more preferably 50,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, and even more preferably 350,000 or less. <1> ~ <14> The agent described in any one of the items. <16> The main chain of the polymer is composed of a polysaccharide or a polysaccharide derivative, and the weight-average molecular weight of the polymer is preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, even more preferably 50,000 or more, even more preferably 100,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, and even more preferably 350,000 or less. <1> ~ <15> The agent described in any one of the items. <17> The main chain of the polymer is composed of a copolymer of a monomer having a sulfobetaine group and an alkyl (meth)acrylate, and the weight-average molecular weight of the polymer is preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, even more preferably 50,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, even more preferably 300,000 or less, even more preferably 200,000 or less, even more preferably 150,000 or less, and even more preferably 100,000 or less. <1> ~ <15> The agent described in any one of the items. <18> The ratio (ΔD / ΔF) is preferably 0.16 or more, preferably 0.50 or less, more preferably 0.45 or less, and even more preferably 0.40 or less. <1> ~ <17> The agent described in any one of the items. <19> The underwater contact angle is preferably 130° or more, more preferably 140° or more, even more preferably 142° or more, and preferably 160° or less, more preferably 155° or less, and even more preferably 150° or less. <1> ~ <18> The agent described in any one of the items. <20> A method for inhibiting bacterial adhesion, comprising the step of physically adsorbing a polymer onto a solid surface with an aqueous solution containing a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chains and at least one of the main chain and side chains being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the quartz crystal microbalancing method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.15 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater. <21> A method for inhibiting biofilm formation, comprising the step of physically adsorbing a polymer onto a solid surface with an aqueous solution containing a polymer having a hydrophobic group with 3 or more carbon atoms at the end of its side chains and at least one of the main chain and side chains being hydrophilic, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: By the quartz crystal microbalancing method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.15 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater. <22> The hydrophobic group of the polymer is preferably one or more functional groups selected from the group consisting of hydrocarbyl groups, fluoroalkyl groups, and silicone groups, and more preferably a hydrocarbyl group. <20> or <21> Methods used. <23> The hydrocarbyl group is preferably one or more selected from the group consisting of a linear or branched alkyl group, a phenyl group, an orthotril group, a metatril group, a paratril group, a biphenyl group, and a benzyl group. <22> Methods used. <24> The number of carbon atoms in the hydrocarbyl group is preferably 3 to 20, more preferably 4 to 18, even more preferably 5 to 16, and even more preferably 6 to 16. <22> or <23> Methods used. <25> The polymer has a hydrophilic group in at least one of its main chain and side chains, wherein the hydrophilic group is preferably one or more functional groups selected from the group consisting of anionic groups, cationic groups, betaine groups, oxyalkylene groups, hydroxyl groups, amide groups, carboxyl groups, amino groups, and ester groups; more preferably one or more functional groups selected from the group consisting of anionic groups, betaine groups, oxyalkylene groups, and hydroxyl groups; and even more preferably one or more functional groups selected from the group consisting of phosphobetaine groups, sulfobetaine groups, oxyethylene groups, and hydroxyl groups. <20> ~ <24> The method described in any one of the items. <26> The polymer has hydrophilic groups in at least one of its main chain and side chains, and the ratio (molar ratio) of hydrophilic groups to hydrophobic groups in the polymer is preferably 20 / 80 or more and 99.9 / 0.1 or less, more preferably 30 / 70 or more and 99.5 / 0.5 or less, even more preferably 40 / 60 or more and 99.3 / 0.7 or less, and even more preferably 50 / 50 or more and 99.0 / 1.0 or less. <20> ~ <25> The method described in any one of the items. <27> The main chain of the polymer is composed of a polysaccharide or a polysaccharide derivative. <20> ~ <26> The method described in any one of the items. <28> The polysaccharide is preferably cellulose or guar gum, more preferably cellulose. <27> Methods used. <29> The polysaccharide derivative is preferably one or more selected from the group consisting of cellulose derivatives or guar gum derivatives, more preferably cellulose derivatives, even more preferably hydroxyethylcellulose and hydroxypropylcellulose, and even more preferably hydroxyethylcellulose. <27> or <28> Methods used. <30> The main chain of the polymer is composed of a cellulose derivative. <20> ~ <29> The method described in any one of the items. <31> The polymer has a betaine group in its side chain. <20> ~ <30> The method described in any one of the items. <32> The betaine group is preferably a sulfobetaine group, a carbobetaine group, or a phosphobetaine group, more preferably a sulfobetaine group. <31> Methods used. <33> The polymer is preferably a copolymer of a monomer having a sulfobetaine group and an alkyl (meth)acrylate, more preferably a [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / alkyl methacrylate copolymer, and even more preferably a [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / alkyl methacrylate copolymer having a hydrocarbon group with 3 to 20 carbon atoms. <20> ~ <32> The method described in any one of the items. <34> The weight-average molecular weight of the polymer is preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, and even more preferably 50,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, and even more preferably 350,000 or less. <20> ~ <33> The method described in any one of the items. <35> The main chain of the polymer is composed of a polysaccharide or a polysaccharide derivative, and the weight-average molecular weight of the polymer is preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, even more preferably 50,000 or more, even more preferably 100,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, and even more preferably 350,000 or less. <20> ~ <34> The method described in any one of the items. <36> The main chain of the polymer is composed of a copolymer of a monomer having a sulfobetaine group and an alkyl (meth)acrylate, and the weight-average molecular weight of the polymer is preferably 5,000 or more, more preferably 10,000 or more, even more preferably 30,000 or more, even more preferably 50,000 or more, and preferably 500,000 or less, more preferably 400,000 or less, even more preferably 300,000 or less, even more preferably 200,000 or less, even more preferably 150,000 or less, and even more preferably 100,000 or less. <20> ~ <34> The method described in any one of the items. <37> The ratio (ΔD / ΔF) is preferably 0.16 or more, preferably 0.50 or less, more preferably 0.45 or less, and even more preferably 0.40 or less. <20> ~ <36> The method described in any one of the items. <38> The underwater contact angle is preferably 130° or more, more preferably 140° or more, even more preferably 142° or more, and preferably 160° or less, more preferably 155° or less, and even more preferably 150° or less. <20> ~ <37> The method described in any one of the items. <39> The above treatment is carried out by immersing the surface of the solid in an aqueous solution containing the polysaccharide. <20> ~ <38> The method described in any one of the items. <40> The solid is preferably one or more selected from the group consisting of polyester, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, polytetrafluoroethylene, polyethylene, polypropylene, stainless steel, and glass, and more preferably one or more selected from the group consisting of polyethylene terephthalate, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, and stainless steel. <20> ~ <39> The method described in any one of the items. <41> A screening method for bacterial adhesion inhibitors containing polymers, wherein the following conditions 1' and 2 are used as indicators. Condition 1': By the quartz crystal microbalancing method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.06 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater. <42> This is a screening method for bacterial adhesion inhibitors that suppress the adhesion of bacteria to solid surfaces. <41> Methods used. <43> The solid is preferably one or more selected from the group consisting of polyester, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, polytetrafluoroethylene, polyethylene, polypropylene, stainless steel, and glass, and more preferably one or more selected from the group consisting of polyethylene terephthalate, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, and stainless steel. <42> Methods used. <44> A screening method for biofilm formation inhibitors containing polymers, wherein the following conditions 1' and 2 are used as indicators. Condition 1': By the quartz crystal microbalancing method, the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [ ] is 0.06 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater. <45> This is a screening method for biofilm formation inhibitors that suppress the formation of biofilms on solid surfaces. <44> Methods used. <46> The solid is preferably one or more selected from the group consisting of polyester, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, polytetrafluoroethylene, polyethylene, polypropylene, stainless steel, and glass, and more preferably one or more selected from the group consisting of polyethylene terephthalate, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, and stainless steel. <45> Methods used. <47> The ratio (ΔD / ΔF) is preferably 0.10 or more, more preferably 0.15 or more, even more preferably 0.16 or more, and preferably 0.50 or less, more preferably 0.45 or less, and even more preferably 0.40 or less. <41> ~ <46> The method described in any one of the items. <48> The underwater contact angle is preferably 130° or more, more preferably 140° or more, even more preferably 142° or more, and preferably 160° or less, more preferably 155° or less, and even more preferably 150° or less. <41> ~ <47> The method described in any one of the items. [Examples]

[0061] [Preparing the polymer] The following polymers for use as bacterial adhesion inhibitors were prepared, and the weight-average molecular weight of each polymer was measured. The measurement results are shown in Table 1.

[0062] Details of the raw materials and reagents used in the preparation of each polymer are as follows. • Hydroxyethylcellulose (HEC(1)): "Natrosol® 250 JR", manufactured by Ashland; weight-average molecular weight 150,000 • Hydroxyethylcellulose (HEC(2)): "Natrosol® 250 GR", manufactured by Ashland; weight-average molecular weight 300,000 Isopropyl alcohol: Manufactured by Marubeni Chemix Corporation • 48% by mass sodium hydroxide aqueous solution: Manufactured by Nankai Chemical Industry Co., Ltd. • Lauryl glycidyl ether: "Epogosei (registered trademark) LA(D)", manufactured by Yokkaichi Gosei Co., Ltd. • 2-Ethylhexylglycidyl ether: "EpoGose (registered trademark) 2EH", manufactured by Yokkaichi Gosei Co., Ltd. Phenylglycidyl ether: Manufactured by Tokyo Chemical Industry Co., Ltd. • Orthocresyl glycidyl ether: Manufactured by Yokkaichi Synthetic Co., Ltd. • Benzyl bromide: Manufactured by Tokyo Chemical Industry Co., Ltd. • n-butyl methacrylate: Manufactured by Fujifilm Wako Pure Chemical Corporation • 2-(dimethylamino)ethyl methacrylate: Manufactured by Fujifilm Wako Pure Chemical Corporation • 2,2'-Azobis(2-methylbutyronitrile): Manufactured by Fujifilm Wako Pure Chemical Corporation • Methyl ethyl ketone: Manufactured by Fujifilm Wako Pure Chemical Corporation • 2,2,2-trifluoroethanol: Manufactured by Tokyo Chemical Industry Co., Ltd. • 1,3-propanesultone: Manufactured by Tokyo Chemical Industry Co., Ltd. • Acrylic acid: "98% GAA", manufactured by Toagosei Co., Ltd. • Stearyl acrylate: "STA", manufactured by Osaka Organic Chemical Industry Co., Ltd. • V-601 (2,2'-Azobis(isobutyrate)dimethyl): Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.; Initiator Hexane: Manufactured by Fujifilm Wako Pure Chemical Corporation • Polyethylene glycol methacrylate (9): "Bremmer (registered trademark) PME-400", manufactured by NOF Corporation. • Lauryl methacrylate (dodecyl methacrylate): Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Acetone: Manufactured by Fujifilm Wako Pure Chemical Corporation • V-65B (2,2'-Azobis(2,4-dimethylvaleronitrile)): Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.; Initiator

[0063] <Polymer 1:C12-HEC(1)> In a 1L separable flask, 90g of HEC(1) was placed, and under a nitrogen gas atmosphere, 73.7g of deionized water and 406.0g of isopropyl alcohol were added. The mixture was stirred with a stirring blade at 200 rpm for 5 minutes, and then 10.6g of 48% by mass sodium hydroxide aqueous solution was added and the mixture was stirred at 40°C for 30 minutes. Next, 3.8 g of lauryl glycidyl ether was added and the mixture was stirred at 80°C for 13 hours to allow it to react. After cooling to below 50°C, 10.6 g of 90% by mass aqueous acetic acid solution was added and the mixture was stirred for 30 minutes to neutralize it. The obtained suspension was evenly distributed into two 500 mL centrifuge tubes and centrifuged using a high-speed refrigerated centrifuge ("CR21G III", Hitachi Koki Co., Ltd.; 1500 g, 40 seconds). The supernatant recovered by decantation was redispersed with an equal volume of 85% by mass aqueous solution of isopropyl alcohol and centrifuged again. The redispersion and centrifugation operations were repeated in the same manner, and after the third centrifugation, the precipitate was collected and dried under reduced pressure overnight at 80°C in a vacuum dryer ("VR-420", Advantec Toyo Co., Ltd.), and then pulverized using a grinder ("Extreme Mill MX-1200XTM", Waring Inc.) to obtain powdered lauryl glycidyl ether-modified HEC (C12-HEC(1)).

[0064] The weight-average molecular weight of C12-HEC(1) was determined by gel permeation chromatography (GPC) under the following measurement conditions. The results are shown in Table 1. (Measurement conditions) • Column: "TSKgel(registered trademark) α-M" (manufactured by Tosoh Corporation) Column temperature: 40°C • Eluent: Ethanol / water (volume ratio 3 / 7), 50 mmol / L lithium bromide, 1% by mass acetic acid ·Flow rate: 0.6mL / min • Sample concentration: 1 mg / L • Sample injection volume: 100 μL • Detector: Differential refractive index (RI) detector • Standard sample: polyethylene glycol

[0065] <Polymer 2: SBMA / BMA (60 / 40)> A stirrer tip, 7.88 g of n-butyl methacrylate, 13.13 g of 2-(dimethylamino)ethyl methacrylate, 0.14 g of 2,2'-azobis(2-methylbutyronitrile), and 21.90 g of methyl ethyl ketone were placed in a round-bottom flask and the mixture was purged with nitrogen gas for 30 minutes. The mixture was stirred and reacted under a nitrogen atmosphere at 67°C for 8 hours, after which it was cooled on ice under an atmospheric atmosphere and dried to obtain a solid. 6.00 g of the obtained solid was placed in a round-bottom flask, and 24.00 g of 2,2,2-trifluoroethanol and 3.52 g of 1,3-propanesultone were added to dissolve the mixture. The reaction was carried out with stirring at 50°C for 5 hours. The reaction product was dried under reduced pressure to obtain a solid of [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate (molar ratio 60 / 40) copolymer (SBMA / BMA(60 / 40)).

[0066] The weight-average molecular weight of SBMA / BMA(60 / 40) was determined by static light scattering (SLS) under the following measurement conditions, and a Zimm plot was created. The results are shown in Table 1. (Measurement conditions) • Equipment: Light scattering photometer "DLS-7000" (manufactured by Otsuka Electronics Co., Ltd.) Wavelength: 632.8nm (helium-neon laser) ·Scattering angle: 30°~150°, 10° intervals ·Measurement temperature: 25℃ • Solvent: 2,2,2-trifluoroethanol • Differential refractometer: "DRM-3000" (manufactured by Otsuka Electronics Co., Ltd.)

[0067] <Polymer 3: Phenyl-HEC(2)> In a 1L separable flask, 80g of HEC(2) was placed, and under a nitrogen gas atmosphere, 58.3g of deionized water and 343.0g of isopropyl alcohol were added. The mixture was stirred with a stirring blade at 200 rpm for 5 minutes, and then 9.0g of 48% by mass sodium hydroxide aqueous solution was added and the mixture was stirred at 40°C for 30 minutes. Next, 7.1 g of phenylglycidyl ether was added and the mixture was stirred at 80°C for 13 hours to allow it to react. After cooling to below 50°C, 9.0 g of 90% by mass aqueous acetic acid solution was added and the mixture was stirred for 30 minutes to neutralize it. The obtained suspension was evenly distributed into two 500 mL centrifuge tubes and centrifuged using a high-speed refrigerated centrifuge ("CR21G III", Hitachi Koki Co., Ltd.; 1500 g, 40 seconds). The supernatant recovered by decantation was redispersed with an equal volume of 87% by mass aqueous solution of isopropyl alcohol and centrifuged again. The redispersion and centrifugation operations were repeated in the same manner, and after the third centrifugation, the precipitate was collected and dried under reduced pressure overnight at 80°C in a vacuum dryer ("VR-420", Advantec Toyo Co., Ltd.), and then pulverized using a pulverizer ("Extreme Mill MX-1200XTM", Waring Inc.) to obtain powdered Phenyl-HEC(2). Furthermore, the weight-average molecular weight of Phenyl-HEC(2) can be considered to be the same as the weight-average molecular weight of the HEC used in the synthesis.

[0068] <Polymer 4:C12-HEC(2)> In a 1L separable flask, 500g of HEC(2) was placed, and under a nitrogen gas atmosphere, 390.2g of deionized water and 2207.6g of isopropyl alcohol were added. The mixture was stirred with a stirring blade at 200 rpm for 5 minutes, and then 57.8g of 48% by mass sodium hydroxide aqueous solution was added and the mixture was stirred at 40°C for 30 minutes. Next, 21.72 g of lauryl glycidyl ether was added and the mixture was stirred at 80°C for 13 hours to allow it to react. After cooling to below 50°C, 57.8 g of 90% by mass aqueous acetic acid solution was added and the mixture was stirred for 30 minutes to neutralize it. The obtained suspension was evenly distributed into two 500 mL centrifuge tubes and centrifuged using a high-speed refrigerated centrifuge ("CR21G III", Hitachi Koki Co., Ltd.; 1500 g, 40 seconds). The supernatant recovered by decantation was redispersed with an equal volume of 87% by mass aqueous solution of isopropyl alcohol and centrifuged again. The redispersion and centrifugation operations were repeated in the same manner, and after the third centrifugation, the precipitate was collected and dried under reduced pressure overnight at 80°C in a vacuum dryer ("VR-420", Advantec Toyo Co., Ltd.), and then pulverized using a pulverizer ("Extreme Mill MX-1200XTM", Waring Corporation) to obtain powdered C12-HEC(2). Furthermore, the weight-average molecular weight of C12-HEC(2) can be considered to be the same as the weight-average molecular weight of the HEC used in the synthesis.

[0069] <Polymer 5:OCR-HEC(1)> In a 1L separable flask, 70g of HEC(1) was placed, and under a nitrogen gas atmosphere, 53.7g of deionized water and 306.8g of isopropyl alcohol were added. The mixture was stirred with a stirring blade at 200 rpm for 5 minutes, and then 8.0g of 48% by mass sodium hydroxide aqueous solution was added and the mixture was stirred at 40°C for 30 minutes. Next, 7.6 g of orthocresyl glycidyl ether was added and the mixture was stirred at 80°C for 13 hours to allow it to react. After cooling to below 50°C, 8.0 g of 90% by mass aqueous acetic acid solution was added and the mixture was stirred for 30 minutes to neutralize it. The obtained suspension was evenly distributed into two 500 mL centrifuge tubes and centrifuged using a high-speed refrigerated centrifuge ("CR21G III", Hitachi Koki Co., Ltd.; 1500 g, 40 seconds). The supernatant recovered by decantation was redispersed with an equal volume of 87% by mass aqueous solution of isopropyl alcohol and centrifuged again. The redispersion and centrifugation operations were repeated in the same manner, and after the third centrifugation, the precipitate was collected and dried under reduced pressure overnight at 80°C in a vacuum dryer ("VR-420", Advantec Toyo Co., Ltd.), and then pulverized using a pulverizer ("Extreme Mill MX-1200XTM", Waring Corporation) to obtain powdered OCR-HEC(1). Furthermore, the weight-average molecular weight of OCR-HEC(1) can be considered to be the same as the weight-average molecular weight of the HEC used in the synthesis.

[0070] <Polymer 6:OCR-HEC(2)> In a 1L separable flask, 80g of HEC(2) was placed, and under a nitrogen gas atmosphere, 58.3g of deionized water and 343.0g of isopropyl alcohol were added. The mixture was stirred with a stirring blade at 200 rpm for 5 minutes, and then 9.0g of 48% by mass sodium hydroxide aqueous solution was added and the mixture was stirred at 40°C for 30 minutes. Next, 8.8 g of orthocresyl glycidyl ether was added and the mixture was stirred at 80°C for 13 hours to allow it to react. After cooling to below 50°C, 9.0 g of 90% by mass aqueous acetic acid solution was added and the mixture was stirred for 30 minutes to neutralize it. The obtained suspension was evenly distributed into two 500 mL centrifuge tubes and centrifuged using a high-speed refrigerated centrifuge ("CR21G III", manufactured by Hitachi Koki Co., Ltd.; 1500 g, 40 seconds). The supernatant recovered by decantation was redispersed with an equal volume of 87% by mass aqueous solution of isopropyl alcohol and centrifuged again. The redispersion and centrifugation operations were repeated in the same manner, and after the third centrifugation, the precipitate was collected and dried under reduced pressure overnight at 80°C in a vacuum dryer ("VR-420", manufactured by Advantec Toyo Co., Ltd.), and then pulverized using a pulverizer ("Extreme Mill MX-1200XTM", manufactured by Waring) to obtain powdered OCR-HEC(2). Furthermore, the weight-average molecular weight of OCR-HEC(2) can be considered to be the same as the weight-average molecular weight of the HEC used in the synthesis.

[0071] <Polymer 7:2EH-HEC(1)> In a 1L separable flask, 90g of HEC(1) was placed, and under a nitrogen gas atmosphere, 61.9g of deionized water and 414.4g of isopropyl alcohol were added. The mixture was stirred with a stirring blade at 200 rpm for 5 minutes, and then 10.6g of 48% by mass sodium hydroxide aqueous solution was added and the mixture was stirred at 40°C for 30 minutes. Next, 9.0g of 2-ethylhexylglycidyl ether was added and the mixture was stirred at 80°C for 13 hours to allow it to react. After cooling to below 50°C, 10.6g of 90% by mass aqueous acetic acid solution was added and the mixture was stirred for 30 minutes to neutralize it. The obtained suspension was evenly distributed into two 500 mL centrifuge tubes and centrifuged using a high-speed refrigerated centrifuge ("CR21G III", Hitachi Koki Co., Ltd.; 1500 g, 40 seconds). The supernatant recovered by decantation was redispersed with an equal volume of 87% by mass aqueous solution of isopropyl alcohol and centrifuged again. The redispersion and centrifugation operations were repeated in the same manner, and after the third centrifugation, the precipitate was collected and dried under reduced pressure overnight at 80°C in a vacuum dryer ("VR-420", Advantec Toyo Co., Ltd.), and then pulverized using a pulverizer ("Extreme Mill MX-1200XTM", Waring Corporation) to obtain powdered 2EH-HEC(1). Furthermore, the weight-average molecular weight of 2EH-HEC(1) can be considered to be the same as the weight-average molecular weight of the HEC used in the synthesis.

[0072] <Polymer 8:Bn-HEC(1)> In a 1L separable flask, 90g of HEC(1) was placed, and under a nitrogen gas atmosphere, 61.9g of deionized water and 414.4g of isopropyl alcohol were added. The mixture was stirred with a stirring blade at 200 rpm for 5 minutes, and then 10.6g of 48% by mass sodium hydroxide aqueous solution was added and the mixture was stirred at 40°C for 30 minutes. Next, 11.1 g of benzyl bromide was added and the mixture was stirred at 60°C for 5 hours to allow it to react. After cooling to below 50°C, 10.6 g of 90% by mass aqueous acetic acid solution was added and the mixture was stirred for 30 minutes to neutralize it. The obtained suspension was evenly distributed into two 500 mL centrifuge tubes and centrifuged using a high-speed refrigerated centrifuge ("CR21G III", Hitachi Koki Co., Ltd.; 1500 g, 40 seconds). The supernatant recovered by decantation was redispersed with an equal volume of 87% by mass aqueous solution of isopropyl alcohol and centrifuged again. The redispersion and centrifugation operations were repeated in the same manner, and after the third centrifugation, the precipitate was collected and dried under reduced pressure overnight at 80°C in a vacuum dryer ("VR-420", Advantec Toyo Co., Ltd.), and then pulverized using a pulverizer ("Extreme Mill MX-1200XTM", Waring Inc.) to obtain powdered Bn-HEC(1). Furthermore, the weight-average molecular weight of Bn-HEC(1) can be considered to be the same as the weight-average molecular weight of the HEC used in the synthesis.

[0073] <Polymer 9:AA / SA(90 / 10)> 74.68 g of isopropyl alcohol was placed in a 500 mL separable flask and stirred at 100 rpm with a stirring blade under a nitrogen gas atmosphere. The temperature was raised to 80°C, and a mixed solution of 180.90 g of acrylic acid, 89.10 g of stearyl acrylate, 102.91 g of isopropyl alcohol, and 1.44 g of V-601 was added dropwise over 4 hours. The reaction system was maintained at 80°C and stirred for another hour. Then, an initiator solution of 0.72 g of V-601 dissolved in 6.5 g of IPA was added dropwise over 30 minutes, and the reaction was carried out with stirring at 80°C for 6 hours. An excess amount of hexane was added to the solution of the reaction product, and the precipitated material was collected and dried under reduced pressure at 80°C to obtain a solid acrylic acid / stearyl acrylate (molar ratio 90 / 10) copolymer (AA / SA(90 / 10)).

[0074] The weight-average molecular weight of AA / SA(90 / 10) was determined by GPC under the following measurement conditions. The results are shown in Table 1. (Measurement conditions) • Columns: "TSKgel(registered trademark) α-M" (manufactured by Tosoh Corporation), 2 pieces Column temperature: 40°C • Eluent: Dimethylformamide, 50 mmol / L lithium bromide, 60 mmol / L phosphoric acid ·Flow rate: 0.6mL / min • Sample concentration: 5 mg / L • Sample injection volume: 100 μL • Detector: RI detector • Standard sample: Polystyrene

[0075] <Polymer 10:PEG(9)MA / LMA(56 / 44)> In a 300 mL separable flask, 56.0 g of polyethylene glycol methacrylate (9), 24.0 g of lauryl methacrylate, and 72.0 g of acetone were placed. The mixture was stirred at 180 rpm with a stirring blade under a nitrogen gas atmosphere, the temperature was raised to 65°C, and an initiator solution of 0.80 g of V-65 dissolved in 8 g of acetone was added. The mixture was stirred for 6 hours to allow the reaction to proceed. The reaction product was dried under reduced pressure at 80°C to obtain a viscous liquid of polyethylene glycol methacrylate (9) / lauryl methacrylate copolymer (molar ratio 56 / 44) (PEG(9)MA / LMA(56 / 44)).

[0076] The weight-average molecular weight of PEG(9)MA / LMA(56 / 44) was determined by GPC under the following measurement conditions. The results are shown in Table 1. (Measurement conditions) • Columns: "Shodex(registered trademark) GPC K-806L" (manufactured by Showa Denko Corporation), 2 pieces Column temperature: 40°C • Eluent: Chloroform, 1 mmol / LN,N-dimethyldodecylamine ("Farmin® DM20", manufactured by Kao Corporation) ·Flow rate: 1.0mL / min • Sample concentration: 5 mg / L • Sample injection volume: 100 μL • Detector: RI detector • Standard sample: Polystyrene

[0077] <Polymer 11: SBMA / BMA (95 / 5)> A stirrer tip, 1.00 g of n-butyl methacrylate, 21.00 g of 2-(dimethylamino)ethyl methacrylate, 0.14 g of 2,2'-azobis(2-methylbutyronitrile), and 21.90 g of methyl ethyl ketone were placed in a round-bottom flask and the flask was purged with nitrogen gas for 30 minutes. The mixture was stirred and reacted under a nitrogen gas atmosphere at 67°C for 8 hours, after which it was cooled on ice under an air atmosphere and dried to obtain a solid. 6.00 g of the obtained solid was placed in a round-bottom flask, and 24.00 g of 2,2,2-trifluoroethanol and 5.57 g of 1,3-propanesultone were added to dissolve the mixture. The reaction was carried out with stirring at 50°C for 5 hours. The reaction product was dried under reduced pressure to obtain a solid of [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate (molar ratio 95 / 5) copolymer (SBMA / BMA(95 / 5)).

[0078] The weight-average molecular weight of SBMA / BMA(95 / 5) was determined in the same manner as the weight-average molecular weight of polymer 2. The results are shown in Table 1.

[0079] [Preparation of polymer sample solution (bacterial adhesion inhibitor)] For polymers 1 and 3-10, 0.1 g of each polymer was mixed with deionized water to make a total of 100.0 g, and a 0.1% by mass polymer sample solution was prepared. For polymers 2 and 11, 0.1 g of each polymer was mixed with a 1% by mass aqueous solution of sodium chloride to make a total of 100.0 g, and a 0.1% by mass polymer sample solution was prepared.

[0080] [Energy dissipation change ΔD[×10 -6 [The ratio of ΔD to the frequency change ΔF[Hz] (ΔD / ΔF)] The sensor portion of a quartz crystal oscillator is coated with polyester T synthesized by the following method, and the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] are measured for various polymer sample solutions (bacterial adhesion inhibitors) in water with a hardness of 4°dH. -6The following values ​​were measured using the QCM-D measuring device, and ΔD / ΔF was determined. For various polymer sample solutions (bacterial adhesion inhibitors), the frequency change ΔF [Hz] and energy dissipation change ΔD [×10] were determined. -6 Table 1 shows the values ​​for ΔD / ΔF.

[0081] <Method for synthesizing polyester T> In a 10L four-necked flask, 3631g of bisphenol A propylene oxide (2.2) adduct, 2734g of bisphenol A propylene oxide (3.0) adduct, 1223g of fumaric acid, 4.2g of tert-butylcatechol, and 42g of tin(II) 2-ethylhexanoate were placed. Under a nitrogen atmosphere, the mixture was heated to 200°C and reacted for 6 hours while mixing and stirring. The temperature was then raised to 210°C, 882g of trimellitic anhydride was added, and the mixture was reacted at atmospheric pressure (101.3kPa) for 1 hour. After that, the pressure was reduced to 40kPa and the mixture was reacted for 4 hours to synthesize polyester T.

[0082] <Polyester coating> 0.30 g of the polyester T synthesized above and 29.7 g of chloroform were mixed and stirred for 12 hours, then filtered through a membrane filter ("DISMIC® 13JP020AN", manufactured by Toyo Roshi Co., Ltd.; pore size 0.2 μm) to prepare a 1% by mass chloroform solution of polyester. The prepared solution was applied to the surface of a quartz crystal oscillator ("QSensor QSX 303 SiO2", manufactured by Biolin Scientific) using a spin coater (manufactured by Kyowa Riken Co., Ltd.; 2000 rpm, 60 seconds) to create a polyester-coated quartz crystal oscillator (sensor part).

[0083] <Preparation of water with a hardness of 4°dH> 83.93 g of calcium chloride dihydrate (CaCl2·2H2O, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and 29.02 g of magnesium chloride hexahydrate (MgCl2·6H2O, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were mixed with deionized water to a volume of 1 L, and the mixture was stirred to prepare water with a hardness of 4000°dH. 1 g of this water was diluted with 999 g of deionized water to prepare water with a hardness of 4°dH.

[0084] <QCM-D measurement> Using a QCM-D measurement device, the ΔD / ΔF after stabilization was measured under the following measurement conditions. (Measurement conditions) · Device: "Q-sense E4" (manufactured by Biolin Scientific) · Sample: 0.1 mass% polymer sample solution (bacterial adhesion inhibitor) · Flow rate: 100 μL / min · Temperature: 25 °C · Flow operation: Polymers 1, 3 - 10: Water with a hardness of 4 °dH → Sample → Water with a hardness of 4 °dH Polymers 2, 11: Water with a hardness of 4 °dH → 1 mass% sodium chloride aqueous solution → Sample → 1 mass% sodium chloride aqueous solution → Water with a hardness of 4 °dH

[0085] [Contact angle in water] Sample substrates were prepared using various polymer sample solutions (bacterial adhesion inhibitors), and the contact angle in water was measured by the captive bubble method. The contact angles in water for various polymers are shown in Table 1. A polyethylene terephthalate (PET) substrate not treated with the polymer sample solution (bacterial adhesion inhibitor) was used as a blank and shown in Table 1.

[0086] <Preparation of sample substrate> A PET substrate (25 mm × 75 mm, thickness 1 mm) was immersed in ethanol for 30 minutes for cleaning, then rinsed with ion-exchanged water for 30 seconds on one side each, and dried by nitrogen gas blowing. This PET substrate was immersed in 100 g of the polymer sample solution (bacterial adhesion inhibitor) for 12 hours, then rinsed with ion-exchanged water for 30 seconds on one side each, and dried by nitrogen gas blowing to obtain a treated substrate. A sample substrate with dimensions of 12.5 mm × 25 mm and a thickness of 1 mm was cut out from the treated substrate.

[0087] <Measurement of contact angle in water by the captive bubble method> Using an automatic contact angle meter ("DropMaster DM-500", manufactured by Kyowa Interface Science Co., Ltd.), the contact angle of a 2 μL air bubble in contact with the sample substrate surface in water was measured at room temperature 6 seconds after contact, using the captive bubble method. This measured value was defined as the water contact angle.

[0088] [Table 1]

[0089] [Examples 1-15, Comparative Examples 1-4] The bacterial adhesion was evaluated by performing the bacterial adhesion test described below on sample substrates treated with a polymer sample solution (bacterial adhesion inhibitor) and determining the bacterial adhesion inhibition rate.

[0090] <Preparation of sample substrate> The following substrates, each 1 mm thick and made of various materials, were cleaned by immersion in ethanol for 30 minutes, then rinsed with deionized water for 30 seconds on each side, and dried by nitrogen gas blowing. This substrate was immersed in 100g of polymer sample solution (bacterial adhesion inhibitor) for 12 hours, then rinsed with deionized water for 30 seconds on each side, and dried by nitrogen gas blowing to obtain a treated substrate. A sample substrate measuring 12.5mm x 25mm and 1mm thick was cut from the treated substrate. (Material of the circuit board) • PET: Polyethylene terephthalate, 25mm x 75mm, 1mm thick, manufactured by Engineering Test Service Co., Ltd. • ABS: Acrylonitrile / butadiene / styrene copolymer, 25mm x 140mm, 1mm thick, manufactured by Engineering Test Service Co., Ltd. • PC: Polycarbonate, 26mm x 76mm, 1mm thick, manufactured by Engineering Test Service Co., Ltd. • PS: Polystyrene, 10mm x 140mm, 1mm thick, manufactured by Engineering Test Service Co., Ltd. • PVC: Polyvinyl chloride, 25mm x 140mm, 1mm thick, manufactured by Engineering Test Service Co., Ltd. • SUS304: Stainless steel SUS304, 25mm x 140mm, 1mm thick, manufactured by Engineering Test Service Co., Ltd.

[0091] <Preparation of test bacterial suspension> 100 μL of each of the following bacterial cells, frozen and stored with added glycerol, were cultured on potato dextrose agar (PDA medium; Difco Laboratories) at 30°C for 48 hours. A portion of the formed colonies was collected and diluted with Dulbecco's phosphate-buffered saline (DPBS; calcium and magnesium-free, pH 7.0-7.3) to an OD600 of 0.1 to prepare test bacterial suspensions. (Type of bacterial cell) Rhodotorula: Rhodotorula mucilaginosa; fungus • Roseomonas: Roseomonas mucosa; Gram-negative bacteria Candida: Candida parapsilosis; mold

[0092] <Bacterial adhesion test> A sample substrate and 3 mL of the test bacterial solution were placed in a sterile petri dish ("Azunol Petri Dish," manufactured by AS ONE Corporation; made of polystyrene, 40 mm in diameter, 13.5 mm in height), and the dish was shaken at 110 rpm for 1 hour at room temperature (25°C). Next, the sample substrate was removed, rinsed with 30 mL of DPBS in a beaker, and transferred to another petri dish. Then, 3 mL of a 1000-fold (volume) dilution of a bacterial fluorescent staining dye ("-Bacstain-CFDA solution," Dojin Chemical Laboratories Co., Ltd.; dimethyl sulfoxide (DMSO) solution of 5(6)-carboxyfluorescein diacetic acid) in DPBS was added dropwise, and the sample substrate was immersed. After standing at 37°C for 30 minutes, the sample substrate was rinsed with sterile water and dried by nitrogen gas blowing.

[0093] <Bacterial adhesion suppression rate> Images of stained bacteria on the sample substrate were observed using a confocal laser microscope (manufactured by Carl Zeiss Corporation), and the bacterial adhesion area was calculated using image processing software ("ImageJ"). Table 2 shows the bacterial adhesion inhibition rate [%], calculated as 100(1-S1 / S0), where S0 is the bacterial adhesion area of ​​the untreated (blank) polymer sample solution (bacterial adhesion inhibitor) substrate and S1 is the bacterial adhesion area of ​​the sample substrate. A higher bacterial adhesion inhibition rate, closer to 100%, indicates a superior bacterial adhesion inhibition effect. A bacterial adhesion inhibition rate of 50% or higher, preferably 60% or higher, more preferably 70% or higher, and even more preferably 75% or higher, indicates a good bacterial adhesion inhibition effect.

[0094] [Table 2]

[0095] As can be seen from Tables 1 and 2, when polymers 1 to 8 that satisfy conditions 1 and 2 were used as bacterial adhesion inhibitors (Examples 1 to 15), a high bacterial adhesion inhibition rate was observed. Furthermore, it was found that the bacterial adhesion inhibitor using polymer 1 showed a high rate of bacterial adhesion inhibition against various bacterial species and on substrates of various materials. Furthermore, Tables 1 and 2 show that by using conditions 1' and 2 as indicators, it is possible to screen for antimicrobial adhesion inhibitors that exhibit good antimicrobial adhesion inhibitory effects against various bacterial species and on the surfaces of various solid materials.

Claims

1. A bacterial adhesion inhibitor comprising (A) lauryl glycidyl ether-modified hydroxyethyl cellulose, phenyl glycidyl ether-modified hydroxyethyl cellulose, orthocresyl glycidyl ether-modified hydroxyethyl cellulose, 2-ethylhexyl glycidyl ether-modified hydroxyethyl cellulose, and benzyl-modified hydroxyethyl cellulose, wherein the content ratio (molar ratio) of hydrophilic groups to hydrophobic groups is 50 / 50 or more and 99.0 / 1.0 or less and the weight-average molecular weight is 100,000 or more and 350,000 or less, and (B) [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate copolymer, wherein the content ratio (molar ratio) of hydrophilic groups to hydrophobic groups is 60 / 40 and the weight-average molecular weight is 50,000 or more and 100,000 or less, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: The frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal, obtained by the quartz crystal microbalancing method. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [the value of ΔD] is 0.15 or greater. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

2. A biofilm formation inhibitor comprising (A) lauryl glycidyl ether-modified hydroxyethyl cellulose, phenyl glycidyl ether-modified hydroxyethyl cellulose, orthocresyl glycidyl ether-modified hydroxyethyl cellulose, 2-ethylhexyl glycidyl ether-modified hydroxyethyl cellulose, and benzyl-modified hydroxyethyl cellulose, wherein the content ratio (molar ratio) of hydrophilic groups to hydrophobic groups is 50 / 50 or more and 99.0 / 1.0 or less and the weight-average molecular weight is 100,000 or more and 350,000 or less, and (B) [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate copolymer, wherein the content ratio (molar ratio) of hydrophilic groups to hydrophobic groups is 60 / 40 and the weight-average molecular weight is 50,000 or more and 100,000 or less, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: The frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal, obtained by the quartz crystal microbalancing method. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [the value of ΔD] is 0.15 or greater. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

3. A method for inhibiting bacterial adhesion, comprising the step of physically adsorbing a polymer onto a solid surface with an aqueous solution containing one or more polymers selected from (A) lauryl glycidyl ether-modified hydroxyethyl cellulose, phenyl glycidyl ether-modified hydroxyethyl cellulose, orthocresyl glycidyl ether-modified hydroxyethyl cellulose, 2-ethylhexyl glycidyl ether-modified hydroxyethyl cellulose, and benzyl-modified hydroxyethyl cellulose, having a molar ratio of hydrophilic groups to hydrophobic groups of 50 / 50 or more and a weight-average molecular weight of 100,000 or more, and (B) [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate copolymer, having a molar ratio of hydrophilic groups to hydrophobic groups of 60 / 40 and a weight-average molecular weight of 50,000 or more, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: The frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal, obtained by the quartz crystal microbalancing method. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [the value of ΔD] is 0.15 or greater. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

4. A method for inhibiting biofilm formation, comprising the step of physically adsorbing a polymer onto a solid surface with an aqueous solution containing one or more polymers selected from (A) lauryl glycidyl ether-modified hydroxyethyl cellulose, phenyl glycidyl ether-modified hydroxyethyl cellulose, orthocresyl glycidyl ether-modified hydroxyethyl cellulose, 2-ethylhexyl glycidyl ether-modified hydroxyethyl cellulose, and benzyl-modified hydroxyethyl cellulose, having a molar ratio of hydrophilic groups to hydrophobic groups of 50 / 50 or more and a weight-average molecular weight of 100,000 or more, and (B) [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate copolymer, having a molar ratio of hydrophilic groups to hydrophobic groups of 60 / 40 and a weight-average molecular weight of 50,000 or more, wherein the polymer satisfies the following conditions 1 and 2. Condition 1: The frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal, obtained by the quartz crystal microbalancing method. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [the value of ΔD] is 0.15 or greater. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

5. The method according to claim 3 or 4, wherein the treatment is performed by immersing the surface of the solid in an aqueous solution containing the polymer.

6. The method according to any one of claims 3 to 5, wherein the solid is one or more selected from the group consisting of polyester, acrylonitrile butadiene styrene resin, polycarbonate, polystyrene, polyvinyl chloride, polytetrafluoroethylene, polyethylene, polypropylene, stainless steel, and glass.

7. A method for screening a bacterial adhesion inhibitor comprising one or more polymers selected from (A) lauryl glycidyl ether-modified hydroxyethyl cellulose, phenyl glycidyl ether-modified hydroxyethyl cellulose, orthocresyl glycidyl ether-modified hydroxyethyl cellulose, 2-ethylhexyl glycidyl ether-modified hydroxyethyl cellulose, and benzyl-modified hydroxyethyl cellulose, having a molar ratio of hydrophilic groups to hydrophobic groups of 50 / 50 or more and a weight-average molecular weight of 100,000 or more, and (B) [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate copolymer, having a molar ratio of hydrophilic groups to hydrophobic groups of 60 / 40 and a weight-average molecular weight of 50,000 or more, wherein the following conditions 1' and 2 are used as indicators. Condition 1': The frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal, obtained by the quartz crystal microbalancing method. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [the value of ΔD] is 0.06 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

8. A method for screening biofilm formation inhibitors comprising one or more polymers selected from (A) lauryl glycidyl ether-modified hydroxyethyl cellulose, phenyl glycidyl ether-modified hydroxyethyl cellulose, orthocresyl glycidyl ether-modified hydroxyethyl cellulose, 2-ethylhexyl glycidyl ether-modified hydroxyethyl cellulose, and benzyl-modified hydroxyethyl cellulose, having a molar ratio of hydrophilic groups to hydrophobic groups of 50 / 50 or more and a weight-average molecular weight of 100,000 or more, and (B) [2-(methacryloxy)ethyl]dimethyl(3-sulfopropyl)ammonium hydroxide / n-butyl methacrylate copolymer, having a molar ratio of hydrophilic groups to hydrophobic groups of 60 / 40 and a weight-average molecular weight of 50,000 or more, wherein the following conditions 1' and 2 are used as indicators. Condition 1': The frequency change ΔF [Hz] and energy dissipation change ΔD [×10] of a 0.1 mass% solution of the polymer in water with a hardness of 4°dH for a polyester-coated quartz crystal, obtained by the quartz crystal microbalancing method. -6 The ratio of ΔD to ΔF (ΔD / ΔF) obtained by measuring [the value of ΔD] is 0.06 or higher. Condition 2: The underwater contact angle of the bubbles with respect to the polymer, as measured by the captive bubble method, is 120° or greater.

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