JPH10152533A - Hydrophilic resin and medical material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a hydrophilic resin excellent in hydrophilicity, antifouling properties and biocompatibility and used for medical materiel, etc., by mixing a specific polymer of a (meth)acrylic ester with a specified polymerizable compound, and polymerizing the mixture. SOLUTION: This hydrophilic resin is obtained by polymerizing (A) 1-99wt.% polymer including a (meth)acrylic ester unit of the formula [R<1> and R<2> are each H or methyl ; (n) is 1-10] and (B) 99-1wt.% polymerizable compound liquid at a room temperature. The component A preferably includes <=95wt.% copolymerizable other monomer units based on the whole component A, and the component B preferably is a vinyl monomer such as an alkyl methacrylate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a hydrophilic resin and a medical material. More specifically, the present invention relates to a hydrophilic resin excellent in hydrophilicity, antifouling property, biocompatibility and mechanical strength, and a medical material containing the hydrophilic resin.

[0002]

2. Description of the Related Art Hitherto, a polymer material has been made hydrophilic in order to impart properties such as antifogging property, antistatic property, printability, coloring property and adhesiveness to the polymer material or to improve the performance. Technology is being developed. For example, a method of adding a hydrophilic material such as a surfactant to a material, a carboxylic acid group in a polymer,
There is known a method of copolymerizing and introducing a monomer having a functional group such as a hydroxyl group or an amino group.

However, in the method of adding a hydrophilic material such as a surfactant, there is a problem that the hydrophilic material migrates from the polymer material and the durability is impaired. Although the method of copolymerizing a monomer having a functional group is improved in durability, it is not suitable for imparting physiological properties such as contamination other than hydrophilicity and biocompatibility.

On the other hand, as a method of improving only the surface of a polymer material and imparting properties such as hydrophilicity, there are treatments such as plasma, corona, ultraviolet (UV), electron beam, radiation and the like. It is used for the appearance and surface hydrophilization by surface grafting. In particular, in the case of plasma treatment, many examples are used for improving biocompatibility.
5 (1980) and Industrial Materials Vol. 25, p. 68 (197
7). However, these processing methods
There are problems such as the need for expensive processing equipment and the limitation of the modification depth of the surface layer.

[0005] In order to improve these problems, there has been proposed a method of coating a base polymer with a hydrophilic polymer or a biocompatible polymer. For example, JP
Japanese Patent Publication No. 44590/44 discloses a method of coating a resin grafted with a hydrophilic monomer, and Japanese Patent Publication No. 7-502053 discloses a polymer comprising a specific zwitterionic group and a bonding group to the material surface. Although methods for surface coating are disclosed, these coating methods are suitable for improving the surface layer, but have problems in peeling from materials and durability.

As another method, Japanese Patent Application Laid-Open No.
Japanese Patent No. 4459 discloses an example of a blend of a polymer having a zwitterionic group and another polymer material. Dispersibility deteriorates, and hydrophilicity, biocompatibility, mechanical strength, heat resistance, etc. are not always sufficient.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydrophilic resin which is excellent in hydrophilicity, antifouling property and biocompatibility, and has heat resistance, mechanical strength and durability.

[0008] Another object of the present invention is to provide a medical material containing the hydrophilic resin.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies in view of the above problems, and as a result, when a polymer of a specific (meth) acrylate ester and a specific polymerizable compound are mixed and then polymerized, Found to improve said performance,
The present invention has been completed.

That is, according to the present invention, as the component A, the following general formula (1)

[0011]

Embedded image

(Wherein R ¹ and R ² represent a hydrogen atom or a methyl group, and n represents a number of 1 to 10).
The present invention provides a hydrophilic resin obtained by polymerizing 99% by weight of a polymerizable compound which is a liquid at room temperature as a B component at room temperature.

Further, according to the present invention, there is provided a medical material containing the hydrophilic resin.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The hydrophilic resin of the present invention is obtained by polymerizing a polymer containing a (meth) acrylate unit as the component A and a polymerizable compound which is liquid at room temperature as the component B. Become.

The (meth) acrylate unit contained in the component A is a unit represented by the general formula (1) (hereinafter abbreviated as unit (a)). By having such a unit containing a phosphorylcholine group (a), the hydrophilic resin of the present invention can have hydrophilicity, antifouling property, biocompatibility and the like. The general formula (1)
If n exceeds 10, the strength and processability of the polymer decrease.

As the unit (a), specifically, for example, 2
-(Meth) acryloyloxyethyl-2 '-(trimethylammonio) ethyl phosphate, 2- (meth) acryloyloxypropyl-2'-(trimethylammonio) ethyl phosphate, 2- (meth) acryloyloxyethoxyethyl-2 '-(Trimethylammonio) ethyl phosphate, 2- (meth) acryloyloxydiethoxyethyl-2'-(trimethylammonio) ethylphosphate, 2- (meth) acryloyloxytriethoxyethyl-2 '-(trimethylammonio ) Units provided when ethyl phosphate or the like is polymerized, or mixed units thereof. Among these, a unit provided by 2- (meth) acryloyloxyethyl-2 ′-(trimethylammonio) ethyl phosphate is particularly preferable in terms of economy and availability.

The component A contains the unit (a),
If necessary, it may further contain another copolymerizable monomer unit (hereinafter abbreviated as unit (b)).

The unit (b) can be contained at a blending ratio of 95% by weight or less based on the total amount of the component A. Unit (b)
When the content of is less than or equal to 95% by weight, desired effects of the present invention such as hydrophilicity, antifouling property, biocompatibility and the like expressed by the unit (a) can be obtained.

Specific examples of the unit (b) include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, (meth) (Meth) acrylic acid alkyl esters such as sec-butyl acrylate and 2-ethylhexyl (meth) acrylate; (meth) acrylic acids such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate Hydroxyalkyl monoester; (meth) acrylamide, N, N-
(Meth) acrylic amide monomers such as dimethyl (meth) acrylamide and N-hydroxy (meth) acrylamide; styrenes such as styrene, methylstyrene, α-methylstyrene, chlorostyrene and chloromethylstyrene Monomer; glycidyl (meth) acrylate; a unit provided when (meth) acrylic acid or the like is polymerized; or a mixed unit thereof.

The method for preparing the component A is not particularly limited. For example, a monomer (hereinafter, referred to as a unit) which gives the unit (a) may be used.
A monomer (a)) or a mixture of the monomer (a) and a monomer (hereinafter, simply referred to as a monomer (b)) to give the unit (b), by a known radical polymerization method. A method in which radical polymerization is carried out by a synthetic method, preferably a solution polymerization method, in the presence or absence of a chain transfer agent.

The molecular weight of the component A is not particularly limited, but is preferably in the range of 2,000 to 200,000 in number average molecular weight.

The component B is a liquid at room temperature, and is particularly limited as long as it is a compound that can be polymerized with the component A by a known polymerization method such as a radical polymerization method, a polyaddition polymerization method, or a polycondensation polymerization method. Although not specifically mentioned, for example, those which can be polymerized by a radical polymerization method include vinyl monomers such as alkyl methacrylate, unsaturated polyester-styrene, diallyl phthalate and the like. Examples of the polymer which can be polymerized by the polyaddition polymerization method include polyisocyanate-polyamine, polyisocyanate-polyol, and polyisocyanate-polythiol. Further, phthalic anhydride-glycerin, epoxy resin and the like can be mentioned as those which can be polymerized by the polycondensation polymerization method.

The hydrophilic resin of the present invention is obtained by polymerizing the above component A and component B. The compounding ratio when polymerizing the A component and the B component is 99 to 1% by weight of the B component to 1 to 99% by weight of the A component in the total of the A component and the B component. 5 to 70% by weight, more preferably 1%
It is in the range of 0 to 50% by weight. The ratio of the component A is 1
When the amount is less than the weight%, the effects of the present invention such as hydrophilicity and biocompatibility are not sufficiently exhibited. On the other hand, when the amount of the component A exceeds 99% by weight, the obtained hydrophilic resin cannot be imparted with the physical and chemical properties as the effect of the present invention.

The method of polymerizing the component A and the component B is not particularly limited, but prior to the polymerization reaction, a mixture of the component A dissolved or dispersed in the component B, or the mixture of the component A The reaction is preferably carried out after preparing a mixture impregnated in the component B. In addition, an appropriate solvent can be added to the mixture, if necessary, for the purpose of adjusting the solubility of the component A to the component B. As the solvent, water, methanol, ethanol, isopropyl alcohol, n-butyl alcohol, ethyl acetate, butyl acetate, methylene chloride, chloroform, acetonitrile, tetrahydrofuran, 1,4-dioxane, acetone, methyl ethyl ketone, benzene, toluene, xylene, Examples thereof include dimethyl sulfoxide, dimethylformamide, and mixtures thereof. The solvent can be used in an amount of 0 to 90 parts by weight based on 100 parts by weight of the total of the components A and B.

Examples of the polymerization method for polymerizing the component A and the component B include known polymerization methods such as a radical polymerization method, a polyaddition polymerization method and a polycondensation polymerization method.

When the reaction is carried out by a radical polymerization method, for example, benzoyl peroxide, diisopropylperoxycarbonate, t-butylperoxy-2-ethylhexanoate, t-butylperoxypivalate, t-butylperoxydiisobut Use may be made of tylates, lauroyl peroxide, azobisisobutyronitrile, azobis-2,4-dimethylvaleronitrile, benzoin methyl ether, benzoin ethyl ether and the like.
Further, if necessary, a polymerization accelerator such as an amine or an ammonium may be used in combination. The addition amount of the polymerization initiator,
1 to 100 parts by weight of the total amount of the components A and B
It can be 0 parts by weight or less. The polymerization conditions are as follows:
Depending on the type of polymerization initiator, the polymerization temperature is 20 to 1
It is preferable that the polymerization time is 50 ° C. and the polymerization time is 6 to 120 hours.

In the case of conducting the polyaddition polymerization method, as a polymerization accelerator, for example, tertiary amines such as triethylamine, 1,8-diazabicyclo (5,4,0) undecene-7 (hereinafter abbreviated as DBU), and salts of DBU. An amine; an organotin compound such as dimethyltin dichloride, dibutyltin dilaurate, or the like can be added to 5 parts by weight or less based on 100 parts by weight of the total amount of the components A and B to carry out the reaction.
The polymerization conditions are preferably such that the polymerization temperature is 20 to 150 ° C. and the polymerization time is 0.1 to 48 hours.

In the case of performing the polycondensation polymerization method, an aliphatic polyamine, a tertiary amine, a polycarboxylic acid, an acid anhydride or the like is used as a curing agent based on 100 parts by weight of the total amount of the components A and B. The reaction can be carried out by adding 150 parts by weight or less. Alternatively, the polymerization can be performed without a curing agent. The polymerization conditions are preferably such that the polymerization temperature is 20 to 250 ° C. and the polymerization time is 1 to 48 hours.

In any polymerization method, additives such as an oxidation stabilizer, an ultraviolet absorber, a coloring agent, a plasticizer, a filler, and a flame retardant can be further added during the polymerization.

The operation of the polymerization of the component A and the component B may be performed under an atmosphere of an inert gas such as nitrogen, helium, argon, or the like, in which the air is replaced, or in the atmosphere.
The polymerization can be carried out by heating or light irradiation in a general polymerization reaction vessel, in a desired mold made of metal, glass, plastic, or the like, or in a state of being applied to another material. When a polymerization reaction is performed in a state of being applied to the other material, the obtained cured polymer can be used as it is as the hydrophilic resin of the present invention. Or, for example, a solution,
The polymer obtained in the form of a suspension, powder, or the like may be used as it is as the hydrophilic resin of the present invention, or may be purified as a powder by precipitation or washing with an appropriate solvent, or the powder may be further used as an appropriate solvent. Can be used as the hydrophilic resin of the present invention in the form of a solution or the like by dissolving, dispersing, emulsifying, or the like.

The medical material of the present invention contains the hydrophilic resin of the present invention. Specifically, for example, the hydrophilic resin of the present invention obtained as the above-mentioned polymerized and cured product can be used as it is as the medical material of the present invention, or the hydrophilic resin of the present invention alone or the hydrophilic resin of the present invention can be used. A mixture of a resin and additives such as an oxidation stabilizer, an ultraviolet absorber, a coloring agent, and a plasticizer is formed into a desired shape such as a sheet, a film, or a tube by a melt molding method, a solvent casting method, or the like. The molded article obtained can also be used as the medical material of the present invention. Further, if necessary, the molded article may be further molded by pulverization, cutting, polishing, or the like. Further, a desired product form can be obtained by blending or coating another resin with the hydrophilic resin of the present invention, and can be used as the medical material of the present invention.

The hydrophilic resin of the present invention is not limited to its surface layer, but retains hydrophilicity, antifouling property and biocompatibility throughout the resin of 1 μm or more. They do not impair their properties.

[0033]

The hydrophilic resin of the present invention is a hydrophilic resin obtained by polymerizing a specific (meth) acrylate unit containing a phosphorylcholine group with a specific polymerizable compound. It has excellent soiling and biocompatibility, and also has heat resistance, mechanical strength and durability. For this reason,
The hydrophilic resin of the present invention can be used for general purposes such as antifogging / antistatic resin, paint, optical material, cosmetic material, and the like, specifically, for example, organic glass, chemical fiber for clothing, marine paint, fishing net positive. It can be widely used for antifouling paints, sunglasses, foundations, manicures, etc., and is particularly useful as a hydrophilic resin for medical materials.

Further, since the medical material of the present invention contains the hydrophilic resin, it has excellent hydrophilicity, antifouling property and biocompatibility, and further has heat resistance, mechanical strength and durability, and a catheter, It is useful as a material for dialysis membranes, artificial organs, blood circuits, spectacle lenses, contact lenses, and the like.

[0035]

The present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples.

(Synthesis Example 1) 20 g of 2-methacryloyloxyethyl-2 '-(trimethylammonio) ethyl phosphate (hereinafter abbreviated as MPC) (as monomer (a), monomer (a) and monomer (a) (B)), a mixed solution consisting of 0.2 g of azobisisobutyronitrile (1 part by weight based on 100 parts by weight of monomer (a) as a catalyst) and 80 g of ethanol. The mixture was charged into a 200 ml four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube, and was heated and polymerized at 50 ° C. for 10 hours in a thermostat. After the polymerization, the polymerization liquid was poured into a large amount of diisopropyl ether to precipitate a polymer, which was separated by filtration and dried in vacuum. The obtained polymer (hereinafter, referred to as polymer C)
Was a white powder with a yield of 92%, and its number average molecular weight measured by GPC was 55,800.

(Synthesis Example 2) 10 g of MPC (monomer (a)
As 50% by weight of the total of the monomers (a) and (b)) and 2-hydroxyethyl methacrylate (hereinafter referred to as 2-hydroxyethyl methacrylate).
The same operation as in Synthesis Example 1 was performed except that a mixture of 10 g (abbreviated as HEMA) of 10 g (50 wt% of the total of the monomers (a) and (b) as the monomer (b)) was used. Thus, 17 g of a polymer (hereinafter, referred to as polymer D) was obtained. Polymer D was a white powder with a yield of 85%, and its number average molecular weight by GPC measurement was 63,700.

(Synthesis Example 3) 3 g of MPC (as monomer (a), 30% by weight in the total of monomer (a) and monomer (b)) and 5 g of styrene (as monomer (b)) , 50% by weight of the total of the monomers (a) and (b)) and 2 g of glycidyl methacrylate (hereinafter abbreviated as GMA) (as the monomer (b), 17.8 g of a polymer (hereinafter, referred to as polymer E) was obtained in the same manner as in Synthesis Example 1 except that a mixture with the monomer (b) was used in an amount of 20% by weight. Polymer E was a white powder with a yield of 89%,
Its number average molecular weight by the measuring method was 45,600.

Example 1 Polymer C obtained in Synthesis Example 1
5 g (33% of the total of the A component and the B component as the A component)
3% by weight), methyl methacrylate (hereinafter abbreviated as MMA)
10 g (as component B, 6% of the total of component A and component B)
6.7% by weight), and 50 g of ethanol (as a solvent,
Azobisisobutyronitrile was added to a mixture of 3.33 parts by weight with respect to 1 part by weight of the total of the components A and B).
1 g was added and charged in a 200 ml four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube.
The polymerization was carried out by heating at 60 ° C. for 20 hours in a thermostat. After polymerization,
The polymerization liquid was poured into a large amount of diisopropyl ether to precipitate a polymer, which was separated by filtration and dried in vacuum. The obtained polymer was further dissolved in ethanol, a cast sheet was prepared on a hot plate at 50 to 100 ° C., and a test for evaluating the contact angle, antifouling property and antithrombotic property described below was performed. Table 2 shows the test results.

Example 2 Polymer D obtained in Synthesis Example 2
5 g (33% of the total of the A component and the B component as the A component)
3% by weight), unsaturated polyester (maleic anhydride, phthalic anhydride and propylene glycol, weight ratio 78:
178: 167 polymer) 6 g (40% by weight of the total of component A and component B as component B) and 4 g of styrene
(26.7% by weight of the total of the component A and the component B as the component B) was added to 0.15 ml of a 10% styrene solution of cobalt (II) naphthenate and a dibutyl phthalate solution of methyl ethyl ketone peroxide in 0.15 ml. 4 ml was added and mixed, and poured into a Teflon dish. After being left for 3 hours, it was subjected to a heat treatment in a dryer at 50 ° C. for 1 hour to obtain a sheet of a cured product. An evaluation test was performed on the obtained sheet in the same manner as in Example 1. Table 2 shows the test results.

Example 3 Polymer D obtained in Synthesis Example 2
5 g (25% by weight, based on the total of components A and B, as component A), 10 g of m-xylene diisocyanate (50% by weight, based on the total of components A and B, component B), and 5 g of butanediol (25% by weight of the total of the A component and the B component as the B component)
g was added and poured into a Teflon dish. After leaving at room temperature for 2 hours, it was kept at 60 ° C. for 15 hours to obtain a cured product sheet. An evaluation test was performed on the obtained sheet in the same manner as in Example 1. Table 2 shows the test results.

Example 4 5 g of the polymer D obtained in Synthesis Example 2
(As a component, 19.2% by weight in the total of the components A and B), 15 g of phthalic anhydride (as the component B, 57.7% by weight in the total of the components A and B) and 6 g of glycerin
(23.1% by weight of the total of the component A and the component B as the component B) was stirred for 200 hours in a glass tube under a nitrogen stream.
Heated at ° C for 2 hours. Thereafter, the mixture was transferred to a Teflon dish and further heated at 200 ° C. for 3 hours in a dryer to obtain a sheet of a cured product. An evaluation test was performed on the obtained sheet in the same manner as in Example 1. Table 2 shows the test results.

Example 5 Polymer E obtained in Synthesis Example 3
5 g (33% of the total of the A component and the B component as the A component)
3% by weight) and 10 g of epoxy resin (molecular weight: 1400, softening point: about 100 ° C., epoxy equivalent: 971) (66.7% by weight in the total of the components A and B as the component B)
It was dissolved in a mixed solvent of xylene and ethyl acetate (1: 1). On the other hand, 1 g of benzyldimethylamine was dissolved in 5 ml of the same mixed solvent. The two solutions were mixed and flowed on a Teflon dish, dried in the air to evaporate the solvent, and then heated at 100 ° C. for 30 minutes to obtain a cured sheet. An evaluation test was performed on the obtained sheet in the same manner as in Example 1. Table 2 shows the test results.

Comparative Examples 1 to 5 Polymer sheets were prepared in the same manner as in Examples 1 to 5 except that the polymers obtained in Synthesis Examples 1 to 3 were not added, and evaluation tests were performed. . Table 2 shows the test results.

(Comparative Examples 6 to 10) Discharge device (6c between electrodes)
m, voltage between electrodes 270 V, frequency 60 Hz)
After placing the polymer sheet obtained in Steps 1 to 5, 0.04 Torr
The glow discharge treatment was performed for 5 seconds in an argon atmosphere of r. After exposing the discharged sheet to the air, put it in a test tube,
A 10% by weight aqueous solution of acrylamide was added, and the atmosphere was replaced with argon gas, followed by sealing under reduced pressure. Put the sealed test tube in 8
After leaving still in a thermostat at 0 ° C. for 1 hour, the surface was washed with methanol and dried under vacuum to obtain a graft-treated polymer sheet. An evaluation test of the contact angle and the antifouling property was performed on these with the same operation as in Example 1. Table 2 shows test results
Shown in

(Comparative Examples 11 to 15) 10 ml of a 10% by weight ethanol solution of each of the polymers C to E obtained in Synthesis Examples 1 to 3 and powder 1 of each of the polymers of Comparative Examples 1 to 5
g was mixed at room temperature in the combinations shown in Table 1 to perform polymer blending, and an attempt was made to form a cast sheet on a hot plate at 50 to 100 ° C.
The miscibility of the polymer was poor, no homogeneous sheet was obtained, and no evaluation test could be performed.

[0047]

[Table 1]

The specific operation of the evaluation test will be described in detail below.

Preparation of a sample: A test piece of 10 mm × 10 mm and a thickness of 0.5 mm, and this test piece was rubbed 10 times with wrapping paper (particle diameter: 3 μm) to examine the durability of the surface, and the surface was polished. The following tests were performed.

Measurement of contact angle: Using a contact angle measuring device manufactured by Kyowa Chemical Co., Ltd., the contact angle was measured for both the test piece and the test piece whose surface was not polished by the water droplet method.

Antifouling test: Antifouling properties were examined for both test pieces, which were not subjected to surface polishing, using protein as a contaminant. That is, each prepared polymer test piece was placed in a phosphate buffer solution (pH 7.0) containing 6 mg / ml of albumin, immersed at 37 ° C. for 3 hours, and the polymer was taken out and lightly rinsed with physiological saline. The adsorbed protein was separated from the test piece with a 0.5% aqueous solution of sodium dodecylbenzenesulfonate. The separated protein was quantified by injecting a reagent for protein quantification and UV measurement.

Antithrombotic test: A test piece was placed in the bottom of a glass tube, and rabbit platelet-rich plasma was poured into the test piece. After standing at 37 ° C. for 1 hour, the test piece was taken out and the behavior of adherent platelets was measured by an electron microscope. Was evaluated and evaluated. The symbols in the table indicate: ×: a large amount of adherent platelets Δ: a small amount of adherent platelets 〇: a small amount of adherent platelets.

[0053]

[Table 2]

From the results shown in Table 2, the hydrophilic resin of the present invention was
Since the contact angle is equal to or smaller than that of the comparative example, it is understood that the hydrophilicity is equal to or greater than that of the comparative example. In addition, it can be seen that the antifouling property is excellent since the protein adsorption amount is equal to or smaller than that. Also, from the difference in the results of the contact angle and the antifouling test with and without the surface polishing in Examples 1 to 6 and Comparative Examples 6 to 10, the hydrophilic resin of the present invention was compared with the surface grafted resin. It turns out that the durability is excellent. Furthermore, since the hydrophilic resin of the present invention has a better antithrombotic test result than that of the comparative example, it can be seen that the hydrophilic resin is extremely excellent in biocompatibility. From the above, it can be seen that the hydrophilic resin of the present invention is excellent in all of hydrophilicity, antifouling property and biocompatibility and has good properties.

Continued on the front page (72) Inventor Yasumi Koinuma 32-16 Higashiarai, Tsukuba, Ibaraki Pref. (72) Inventor Kiyoshi 27-1-1, Kasuga, Tsukuba, Ibaraki Pref. 5-6-20 (72) Inventor Kazuhiko Ishihara 3-16-37 Josuihoncho, Kodaira-shi, Tokyo

Claims (3)

[Claims] 1. A component represented by the following general formula (1): (Wherein R ¹ and R ² each represent a hydrogen atom or a methyl group, and n represents a number of 1 to 10), and 1 to 99% by weight of a polymer containing a (meth) acrylate unit represented by the formula: A hydrophilic resin obtained by polymerizing 99 to 1% by weight of a liquid polymerizable compound at room temperature as a component B. 2. The hydrophilic resin according to claim 1, wherein the component A further contains 95% by weight or less of other copolymerizable monomer units in the total amount of the component A. 3. A medical material comprising the hydrophilic resin according to claim 1.