SURFACE TREATMENT LIQUID AND SURFACE TREATMENT METHOD

Abstract

The present invention provides: a surface treatment liquid which is capable of performing good hydrophilization or hydrophobization of the surface of an object to be treated even if the surface treatment liquid does not contain a coating film-forming resin; and a surface treatment method which uses this surface treatment liquid, A surface treatment liquid, comprising a resin (A) and a solvent (C), and wherein a resin having a functional group I that is a nitrogen-containing heterocyclic group and a functional group II that is a functional group other than the functional group I and having one or more groups selected from among hydrophilic groups and hydrophobic groups, and comprising a constituent unit (a1) having the functional group I, and one or more constituent units selected from the group consisting of a constituent unit (a2) having a cationic group in a side chain, and a constituent unit (a3) having an anionic group in a side chain, is used as the resin (A).

Claims

1. A surface treatment liquid, comprising a resin (A) and a solvent (C), wherein the resin (A) has a functional group I that is a nitrogen-containing heterocyclic group and a functional group II that is a functional group other than the functional group I and is one or more groups selected from hydrophilic groups and hydrophobic groups, and the resin (A) comprises a constituent unit (a1) having the functional group I, and one or more constituent units selected from the group consisting of a constituent unit (a2) having a cationic group in a side chain and a constituent unit (a3) having an anionic group in a side chain.

2. The surface treatment liquid according to claim 1, wherein the resin (A) may further comprise other constituent unit (a4) other than the constituent unit (a1), the constituent unit (a2), and the constituent unit (a3), an amount of the constituent unit (a1) in the total constituent units of the resin (A) is 2 mol % or more, a sum of an amount of the constituent unit (a1) and an amount of the constituent unit (a2) is 70 to 100 mol % or 2 to 30 mol % with respect to the total constituent units of the resin (A), when a sum of an amount of the constituent unit (a1) and an amount of the constituent unit (a2) is 70 to 100 mol % with respect to the total constituent units of the resin (A), the amount of the constituent unit (a3) is 0 to 30 mol %, when a sum of an amount of the constituent unit (a1) and an amount of the constituent unit (a2) is 2 to 30 mol % with respect to the total constituent units of the resin (A), an amount of the constituent unit (a3) is 70 to 98 mol %.

3. The surface treatment liquid according to claim 1, wherein the hydrophilic group is a group represented by the following formula (A5):
NHR.sup.1(A5) wherein R.sup.1 is an alkyl group having 1 to 4 carbon atoms, which is substituted with one or more groups selected from the group consisting of an amino group, a sulfonic group, and a hydroxyl group, or a hydrogen atom.

4. The surface treatment liquid according to claim 1, wherein the hydrophobic group is one or more groups selected from the group consisting of a fluorinated hydrocarbon group, a silyl group, and a siloxane group.

5. The surface treatment liquid according to claim 1, wherein the functional group II comprises a hydrophobic group, and the hydrophobic group is derived from a monomer represented by the following formula (A6):
CH.sub.2CR.sup.2(COO).sub.aR.sup.3(A6) wherein R.sup.2 is a hydrogen atom or a methyl group, a is 0 or 1, R.sup.3 is a fluorinated hydrocarbon group, or is a group represented by the following formula (A7):
SiR.sup.4R.sup.5(OSiR.sup.4R.sup.5).sub.nR.sup.6(A7), and R.sup.4, R.sup.5, and R.sup.6 are, each independently a hydrocarbon group having 1 to 6 carbon atoms, and n is an integer of 0 or more.

6. The surface treatment liquid according to claim 1, wherein the functional group II comprises a hydrophilic group, and the hydrophilic group is derived from a monomer represented by the following formula (A8):
CH.sub.2CR.sup.2CONHR.sup.1(A8) wherein R.sup.1 is an alkyl group having 1 to 4 carbon atoms, which is substituted with one or more groups selected from the group consisting of an amino group, a sulfonic group, and a hydroxyl group, and R.sup.2 is a hydrogen atom or a methyl group.

7. The surface treatment liquid according to claim 1, wherein the constituent unit (a2) is a constituent unit derived from a compound represented by the following formula (A2):
CH.sub.2CR.sup.2(CO).sub.aR.sup.10(A2) wherein R.sup.2 is a hydrogen atom or a methyl group, R.sup.10 is a group represented by YR.sup.1R.sup.12, or an amino group, Y is O, or NH, R.sup.11 is a divalent organic group optionally having a substituent, R.sup.12 is an amino group which is optionally substituted with a hydrocarbon group having 1 to 6 carbon atoms, or a quaternary ammonium salt group represented by N.sup.+R.sup.13R.sup.14R.sup.15.Z.sup., R.sup.13, R.sup.14, and R.sup.15 are, each independently a hydrogen atom, or a hydrocarbon group having 1 to 6 carbon atoms, Z.sup. is a counter anion, and a is 0 or 1.

8. The surface treatment liquid according to claim 1, wherein the constituent unit (a3) is a constituent unit derived from a compound represented by the following formula (A3):
CH.sub.2CR.sup.2(CO).sub.bR.sup.17(A3) wherein the formula (A3), R.sup.2 is a hydrogen atom or a methyl group, R.sup.17 is a hydroxyl group, or a group represented by -A-R.sup.8R.sup.19, A is O, or NH, R.sup.18 is a divalent organic group optionally having a substituent, R.sup.19 is a Brnsted acidic group, b is 0 or 1, wherein when b is 0, R.sup.17 is not a hydroxyl group.

9. The surface treatment liquid according to claim 1, further comprising a strong acid (B) having a pKa of 1 or less.

10. The surface treatment liquid according to claim 1, wherein the solvent (C) comprises water.

11. A surface treatment method, comprising bringing the surface treatment liquid according to claim 1 into contact with a treatment target.

12. A surface treatment method comprising bringing the surface treatment liquid according to claim 1 into contact with a surface of the treatment target; and further treating the surface of the treatment target wetted with the surface treatment with a second aqueous treatment liquid other than the surface treatment liquid.

Description

EXAMPLES

[0119] Hereinafter, the present invention will be explained more specifically by way of Examples. However, the present invention is not limited to the following Examples.

Examples 1 to 16 and Comparative Examples 1 to 3

[0120] In each Example and Comparative Example, resin containing the constituent units to be described below in the ratios listed in Table 1 was used as resin (A). The constituent units N1 to N3 are a constituent unit (a1) having a functional group I that is a nitrogen-containing heterocyclic group. Note here that the constituent units N2 and N3 include a nitrogen-containing heterocyclic group as a cationic group, and the constituent unit N2 includes a phenolic hydroxyl group as an anionic group. The constituent units C1 to C3 are a constituent unit (a2) that has a cationic group in a side chain. The constituent units D1D4 are a constituent unit (a3) that has an anionic group in a side chain. The constituent units E1E4 are the constituent unit (a4) other than the constituent unit (a1), constituent unit (a2), and constituent unit (a3).

##STR00039## ##STR00040## ##STR00041##

(Preparation of Surface Treatment Liquid)

[0121] Resins (A) including the constituent units of types and molar ratios described in Tables 1 and 2 were dissolved in pure water such that the concentration became 1 mass % to obtain surface treatment liquid of each Example and Comparative Example.

(Evaluation of Surface Treatment Effect)

[0122] Surface treatment of a PET film was carried out with the following method, by using the surface treatment liquids of Examples 1 to 16 and Comparative Examples 1 to 3, which were obtained with the above-described method. Specifically, a PET film (T100, manufactured by Mitsubishi Polyester Inc.) was immersed in a surface treatment liquid for one minute, the surface of the PET film was rinsed with pure water, and further the surface of the PET film was dried by blowing nitrogen to obtain a surface-treated PET film. The water contact angle on the surface of the PET film after surface treatment was measured using Dropmaster 700 (manufactured by Kyowa Interface Science Co., Ltd.) as follows: a pure water droplet (2.0 L) was dropped onto a surface-treated surface of a substrate, and the contact angle was measured after 10 seconds of dropping. Measurement results of the water contact angles are listed in Tables 1 and 2. Note here that the water contact angle with respect to an untreated PET film is 720.

TABLE-US-00001 TABLE 1 Constituent unit Example Types Property 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 a1 N1 10 5 10 90 50 30 10 90 5 10 30 50 30 N2 5 N3 10 5 50 a2 C1 Hydrophilic 50 70 90 C2 Hydrophilic 90 C3 Hydrophilic 10 a3 D1 Hydrophilic 85 D2 Hydrophilic 95 50 90 5 D3 Hydrophilic 90 45 85 D4 Hydrophilic 10 a4 E1 E2 Hydrophilic 5 E3 Hydrophobic 70 65 E4 Hydrophobic 50 50 Water contact angle 16 17 34 32 27 18 21 35 24 25 21 26 86 88 78 84 after treatment ()

TABLE-US-00002 TABLE 2 Comparative Constituent unit Example Types Property 1 2 3 a1 N1 5 N2 N3 a2 C1 Hydrophilic 15 C2 Hydrophilic C3 Hydrophilic a3 D1 Hydrophilic 100 D2 Hydrophilic 85 D3 Hydrophilic D4 Hydrophilic a4 E1 95 E2 Hydrophilic E3 Hydrophobic E4 Hydrophobic Water contact angle 72 72 70 after treatment ()

[0123] According to Examples, it is shown that use of a surface treatment liquid including a resin (A) having a functional group I that is a nitrogen-containing heterocyclic group and a functional group II that is a functional group other than the functional group I and is one or more groups selected from hydrophilic groups and hydrophobic groups, and including one or more constituent units selected from the group consisting of a constituent unit (a1) that has the functional group I, a constituent unit (a2) that has a cationic group in a side chain, and a constituent unit (a3) that has an anionic group in a side chain can successfully make the surface of the PET film hydrophilic or hydrophobic. On the other hand, according to Comparative Example, the resin (A) does not have a functional group I that is a nitrogen-containing heterocyclic group, or does not include a constituent unit (a2) that has a cationic group in a side chain, and a constituent unit (a3) that has an anionic group in a side chain, it is shown that a desired surface treatment effect is not easily obtained.