JP7072785B2 - Coating solution - Google Patents

Description

The present invention relates to a polycarbonate coating solution having good solvent solubility in a non-halogen solvent and excellent adhesion to a substrate.

Polycarbonate resin is used in mechanical products such as electric appliances and automobiles because of its excellent transparency and moldability, and its excellent mechanical properties such as impact resistance. Among them, a polycarbonate resin solution is known for obtaining a thin film having functionality and for coating an article. (Patent Document 1)
The coating film obtained from the polycarbonate resin solution has excellent durability such as impact resistance, but is inferior in adhesion, and is known to be applied to easily peelable nail polish by utilizing its properties. (Patent Document 2)
Therefore, there was room for improvement in the adhesion between these coating films and the substrate.
On the other hand, from the viewpoint of safety, halogen-based organic solvents such as dichloromethane have become more and more refrained from being used as solvents for polycarbonate resin solutions in recent years, and polycarbonate resin solutions using safer and easier-to-handle solvents have become more popular. I was asked.

Japanese Unexamined Patent Publication No. 4-268365 Japanese Unexamined Patent Publication No. 2014-024789

An object of the present invention is to provide a coating solution capable of forming a polycarbonate film having excellent adhesion to a substrate without using a halogen-based solvent as a main solvent. Further, it is an object of the present invention to provide a method for forming a film using the coating solution and a molded body coated by the method.

As a result of diligent studies to solve the conventional problems, the present inventors have a strong coating film in which the polycarbonate resin having a specific molecular terminal is well soluble in a non-halogen solvent and has strong adhesion to the substrate. It was found that the present invention was completed.
That is, the present invention

[1]
A coating solution containing 0.1 to 50% by mass of a polycarbonate resin having the following structural unit (2) in which the following structural formula (1) is bonded to the molecular end and a non-halogen solvent.

(In the formula (1), R ₁ represents an alkylene group having 1 to 20 carbon atoms or an alkenylene group having 2 to 20 carbon atoms, which may have a substituent. R ₂ to R ₃ are hydrogen and carbon atoms. It represents an alkyl group of 1 to 20, an alkoxy group having 1 to 10 carbon atoms, and an aryl group having 6 to 12 carbon atoms. Z represents an ether bond, a carbonyl group, an ester bond, or a is a single bond. It is an integer of 3. Y represents an ether bond or an ester group.)

(In the formula (2), R ₄ to R ₇ are hydrogen, fluorine, chlorine, bromine, iodine, each of which may have a substituent, an alkyl group having 1 to 20 carbon atoms and an aryl group having 6 to 12 carbon atoms. , An alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and an aralkyl group having 7 to 17 carbon atoms. X is represented by the formula (3).

Here, R ₈ and R ₉ have hydrogen, fluorine, chlorine, bromine, and iodine, respectively, which may have substituents, an alkyl group having 1 to 20 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms, respectively. , Represents an aryl group having 6 to 12 carbon atoms, or represents a group in which R ₈ and R ₉ are combined to form a carbon ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements. R ₁₀ and R ₁₁ may have hydrogen, fluorine, chlorine, bromine, iodine, and substituents, respectively, an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and 2 to 2 carbon atoms, respectively. It represents 12 alkenyl groups and 6 to 12 aryl groups. R ₁₂ is an alkylene group of 1 to 9 which may have a substituent. c represents an integer of 0 to 20, and d represents an integer of 1 to 500. )

[2]
The coating solution according to [1], wherein the structural unit (2) is at least one selected from the group consisting of the following formulas (4) to (11).

[3]
The coating solution according to [1] or [2], wherein Z in the formula (1) is a single bond, R ₁ is an alkylene having 1 to 2 carbon atoms, and R ₂ to R ₃ is hydrogen.

[4]
The coating solution according to any one of [1] to [3], wherein the main component of the non-halogen solvent is a solvent containing at least one of an ester solvent, an ether solvent, a carbonic acid ester solvent, and a ketone solvent. be.

[5]
The coating solution according to any one of [1] to [4], wherein the polycarbonate resin has an extreme viscosity of 0.3 to 2.0 dl / g.

[6]
This is a method for forming a film for removing a non-halogen solvent from the coating solution according to any one of [1] to [5].

[7]
It is a molded body coated by the method described in [6] above.

The polycarbonate resin film obtained from the coating solution of the present invention has the advantages of having stronger adhesion to the substrate and being less likely to be peeled off, as compared with the conventional polycarbonate resin film. Furthermore, this coating solution does not contain a halogen-based solvent, which has a safety problem, as a main solvent, and contributes to the improvement of the coating work environment.

The polycarbonate resin used in the coating solution of the present invention is produced by reacting a monovalent phenol that induces the structural formula (1) at the molecular terminal with a bisphenol that induces the structural unit (2) and a carbonic acid ester-forming compound. A known method used in the production of polycarbonate derived from bisphenol A, for example, a direct reaction between bisphenols and phosgen (phosgen method), or bisphenols and bisaryl carbonate. A method such as an ester exchange reaction (ester exchange method) can be adopted.

The bisphenols that induce the structural unit (2) that is the raw material monomer of the polycarbonate resin of the present invention are represented by the following structural formula (12).

(In the formula, R ₁₃ to R ₁₆ may have hydrogen, fluorine, chlorine, bromine, iodine, each of which may have a substituent, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms, and a carbon number of carbon atoms. It is an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and an aralkyl group having 7 to 17 carbon atoms. W is represented by the formula (13).

Here, R ₁₇ and R ₁₈ have hydrogen, fluorine, chlorine, bromine, and iodine, respectively, which may have substituents, an alkyl group having 1 to 20 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms, respectively. , Represents an aryl group having 6 to 12 carbon atoms, or represents a group in which R ₁₇ and R ₁₈ are combined to form a carbon ring having 5 to 20 carbon atoms or a heterocyclic ring having 5 to 12 elements. R ₁₉ and R ₂₀ may have hydrogen, fluorine, chlorine, bromine, iodine, and substituents, respectively, an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and 2 to 2 carbon atoms, respectively. It represents 12 alkenyl groups and 6 to 12 aryl groups. R ₂₁ is an alkylene group of 1 to 9 which may have a substituent. e represents an integer of 0 to 20, and f represents an integer of 1 to 500. )

Specifically, 4,4'-biphenyldiol, bis (4-hydroxyphenyl) methane, bis (2-hydroxyphenyl) methane, 2,4'-dihydroxydiphenylmethane, bis (4-hydroxyphenyl) ether, bis ( 4-Hydroxyphenyl) sulfone, 2,4'-dihydroxydiphenyl sulfone, bis (2-hydroxyphenyl) sulfone, bis (4-hydroxy-3-methylphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4) -Hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) ketone, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, bis (4-hydroxy) Phenyl) diphenylmethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-methylphenyl) ethane , Bis (4-hydroxy-3-methylphenyl) methane, 2,2-bis (4-hydroxy-3-t-butylphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 1,1- Bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxy-3-methylphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) cycloundecane, 1,1-bis (4-hydroxyphenyl) ) Cyclododecane, 2,2-bis (4-hydroxy-3-allylphenyl) propane, 3,3,5-trimethyl-1,1-bis (4-hydroxyphenyl) cyclohexane, 9,9-bis (4-) Hydroxy-3-ethylphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 9,9-bis (4-hydroxyphenyl) fluorene, α, ω-bis [3- (o-) Hydroxyphenyl) propyl] polydimethyldiphenyl random copolymerized siloxane, α, ω-bis [3- (o-hydroxyphenyl) propyl] polydimethylsiloxane, 4,4'-[1,4-phenylenebis (1-methylethylidene) )] Bisphenol, 4,4'-[1,3-phenylenebis (1-methylethylidene)] Bisphenol, 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl)- 2-Ethylhexane, 1,1-bis (4-hydroxyphenyl) -2 -Methylpropane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) decane, 1,3-bis (4-hydroxyphenyl) -5,7- Examples include dimethyladamantane. These can be used in combination of two or more. Among these, 4,4'-biphenyldiol, bis (4-hydroxyphenyl) methane, bis (2-hydroxyphenyl) methane, 2,4'-dihydroxydiphenylmethane, bis (4-hydroxyphenyl) ether, 2 , 2-Bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane are preferred. Further, it is preferable to use 2,2-bis (4-hydroxy-3-methylphenyl) propane as a main component. When 2,2-bis (4-hydroxyphenyl) propane is used alone, its solubility in a non-halogen organic solvent is low. Therefore, in the present invention, 2,2-bis (4-hydroxyphenyl) propane is used. Not used alone.

The monovalent phenol that induces the structural formula (1) at the end of the molecule is represented by the following structural formula (14).

In formula (14), R ₂₂ represents an alkylene group having 1 to 20 carbon atoms or an alkenylene group having 2 to 20 carbon atoms, which may have a substituent. R ₂₃ to R ₂₄ represent hydrogen, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and an aryl group having 6 to 12 carbon atoms. V represents an ether bond, a carbonyl group, an ester bond, or a single bond. g is an integer of 1 to 3. )

Specifically, p-hydroxyphenethyl alcohol (= tyrosol), m-hydroxyphenethyl alcohol, o-hydroxyphenethyl alcohol, o-hydroxybenzyl alcohol (= salicyl alcohol), p-hydroxybenzyl alcohol, m-hydroxybenzyl alcohol, Examples thereof include vanillyl alcohol, homovanillyl alcohol, 3- (4-hydroxy-3-methoxyphenyl) -1-propanol, cinapyl alcohol, coniferyl alcohol, p-kumalyl alcohol and the like. Of these, p-hydroxyphenethyl alcohol and p-hydroxybenzyl alcohol are preferable, and p-hydroxyphenethyl alcohol is more preferable from the viewpoint of reactivity.

In the phosgene method, the bisphenol of the structural formula (12) is usually reacted with the monovalent phenol of the early structural formula (14) in the presence of an acid binder and a solvent. As the acid binder, for example, pyridine, hydroxide of an alkali metal such as sodium hydroxide and potassium hydroxide, and the like are used, and as the solvent, for example, methylene chloride, chloroform and the like are used. Further, in order to promote the polycondensation reaction, it is preferable to use a catalyst such as a tertiary amine such as triethylamine or a quaternary ammonium salt such as benzyltriethylammonium chloride. The structural formula (14) functions as a degree of polymerization regulator, but in addition, 50 monovalent phenols such as phenol, pt-butylphenol, p-cumylphenol, and long-chain alkyl-substituted phenol are used with respect to the structural formula (14). It is also possible to use it in combination with less than mass%. Further, if desired, an antioxidant such as sodium sulfite or hydrosulfite, or a branching agent such as fluoroglucin or isatin bisphenol may be added in a small amount. The reaction is usually in the range of 0 to 150 ° C, preferably 5 to 40 ° C. The reaction time depends on the reaction temperature, but is usually 0.5 minutes to 10 hours, preferably 1 minute to 2 hours. Further, it is desirable to keep the pH of the reaction system at 10 or higher during the reaction.

On the other hand, in the transesterification method, the bisphenol of the structural formula (12), the monovalent phenol of the early structural formula (14) and the bisaryl carbonate are mixed and reacted at a high temperature under reduced pressure. Examples of bisaryl carbonate include bisallyl carbonates such as diphenyl carbonate, di-p-tolyl carbonate, phenyl-p-tolyl carbonate, di-p-chlorophenyl carbonate and dinaphthyl carbonate. It is also possible to use two or more of these compounds in combination. The reaction is usually carried out at a temperature in the range of 150 to 350 ° C., preferably 200 to 300 ° C., and the degree of reduced pressure is finally preferably 1 mmHg or less, and phenols derived from the bisaryl carbonate produced by the transesterification reaction. Is removed from the system. The reaction time depends on the reaction temperature, the degree of decompression, etc., but is usually about 1 to 24 hours. The reaction is preferably carried out in an atmosphere of an inert gas such as nitrogen or argon. Further, if desired, a small amount of a molecular weight modifier other than the structural formula (14) may be used in combination, or an antioxidant or a branching agent may be added to carry out the reaction.

It is preferable that the polycarbonate resin of the present invention maintains a good balance of solvent solubility, coating property, adhesion, scratch resistance, impact resistance and the like required as a film-forming resin for a coating solution. If the ultimate viscosity of the resin is too low, the scratch resistance and impact resistance strength will be insufficient, and if the ultimate viscosity is too high, the solvent solubility will decrease and the solution viscosity will increase, resulting in a decrease in coating property. As a desirable limit viscosity range, the limit viscosity is preferably in the range of 0.3 to 2.0 dl / g, and more preferably in the range of 0.35 to 1.5 dl / g.

The coating solution of the present invention is a solution in which the polycarbonate resin is dissolved in a solvent containing a non-halogen solvent, and in that state, a film generally called a clear color is formed. Further, a desired dye / pigment can be dissolved or dispersed to form a colored film.

As described above, the solvent of the coating solution of the present invention is a solvent containing a non-halogen solvent, and preferably a solvent containing a non-halogen organic solvent as a main solvent. That is, the main component is a solvent generally used for paints and the like, and specifically, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, 2-ethoxyethyl acetate, 2-methoxy-1-methyl ethyl acetate, ethyl lactate and the like. Ester solvent, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, isophorone and other ketone solvents, dimethyl carbonate, ethyl methyl carbonate and other carbonate solvents, tetrahydrofuran, 1,4-dioxane, diethyl ether, dimethoxymethane, ethyl. Examples thereof include ether solvents such as cellsolve and anisole, and aromatic hydrocarbon solvents such as toluene, ethylbenzene, xylene, pseudocumene and mesitylen. Further, a small amount of an alcohol-based poor solvent such as ethanol or isopropyl alcohol or a hydrocarbon-based poor solvent such as n-heptane, cyclohexane or mineral spirit may be used in combination. Above all, it is preferable to dissolve in an ester-based solvent such as propyl acetate and butyl acetate, which is inexpensive, has good workability, and has relatively high safety, a ketone solvent such as methyl ethyl ketone and cyclohexanone, and an ether solvent such as tetrahydrofuran and dimethoxymethane. In particular, methyl ethyl ketone and propyl acetate are preferable.
Further, since a halogen-based solvent such as dichloromethane has a great influence on the coating work environment, it is not used as the main solvent of the coating solution of the present invention.

The viscosity of the coating solution of the present invention can be arbitrarily set by a desired coating method, but is preferably in the range of 10 to 20000 mPa / s. It is preferably 400 to 20000 mPa / s for airless spray, brush coating and roller coating, 100 to 6000 mPa · s for air spray, and 10 to 500 mPa · s for dip coating and can spray.

Pigments, dyes, colored particles, and light-interfering particles can be added to the coating solution of the present invention in order to enhance the color effect. Examples of the pigments and dyes include azo pigments and phthalocyanine pigments as organic pigments. Specifically, for example, Red No. 104, Red No. 106, Red No. 201, Red No. 202, Red No. 204, Red No. 215. No., Red No. 220, Orange No. 203, Orange No. 204, Blue No. 1, Blue No. 404, Yellow No. 205, Yellow No. 401, Yellow No. 405 and the like. In addition, mica titanium, titanium oxide, iron oxide, tin oxide, zirconium oxide, chromium oxide, bismuth oxychloride, silica, chromium, titanium nitride, titanium, magnesium fluoride to give a white, pearl color, metallic color, and glitter feeling. , Gold, silver, nickel, etc. can also be used. The particles having light coherence are particles that enhance the color effect by reflecting or scattering light, and examples thereof include glass beads, minute shells, and mica. These are preferably added in the range of 0.0001 to 10.0% by mass in the coating, if desired.

Further, if necessary, a rust inhibitor, an antioxidant, a dispersant, an ultraviolet absorber, an antifoaming agent, a leveling agent and the like may be added.

The blending amount of the polycarbonate resin in the coating solution of the present invention depends on the extreme viscosity and solvent solubility, but is preferably 1 to 50% by mass, more preferably 4 to 30% by mass. When the concentration is within the range, the solvent solubility and the coating property are well-balanced, and the workability and the appearance are improved.

The coating film after coating the coating solution of the present invention is less likely to be scratched or peeled off due to rubbing, impact, etc. during transportation or use, as compared with the coating film of the conventional polycarbonate coating solution.

The film thickness after coating the coating solution of the present invention is preferably in the range of 5 to 200 μm, particularly preferably in the range of 10 to 120 μm, and further preferably 15 to 60 μm. A thin film of less than 5 μm is not strong enough to reach the substrate, and if it is too thick over 200 μm, it is likely to peel off due to shrinkage of the film. It will be disadvantageous.

Examples of the present invention are shown below together with comparative examples, and the contents of the invention are shown in detail, but the present invention is not limited to these examples.

<Solvent solubility>
When the polycarbonate resins of Examples and Comparative Examples were dissolved in 5 to 12% by mass of each solvent, the solution in a closed container was shaken with a shaker for 24 hours, and then the presence or absence of undissolved residue was visually confirmed. A has no undissolved residue, and B has undissolved residue.

<Peeling durability>
Adhesive test using JIS K5600-5-6 compliant adhesive cross-cut method (2 mm interval) using Nichiban Co., Ltd. cross-cut test compliant 24 mm wide cellophane tape (registered trademark) (adhesive strength 4.01N / 10 mm) Then, based on the JIS classification index, it was classified by a numerical value from 0 (no peeling) to 5 (almost all peeling), and used as an index of peeling durability.

<Measurement method of extreme viscosity>
A solution of a polycarbonate resin in dichloromethane of 0.5% by mass / volume was determined using a Ubbelohde viscous tube at 20 ° C. and a Huggins constant of 0.45.

<Measuring method of coating solution viscosity>
The viscosity of the coating solution was measured at 25 ° C. with a B-type viscometer.

Example 1
2,2-Bis (4-hydroxy-3-methylphenyl-) propane (hereinafter abbreviated as "BPC": manufactured by Honshu Chemical Industry Co., Ltd.) 102.4 g (0.4 mol) in 1100 ml of a 5 w / w% sodium hydroxide aqueous solution. ), 2.45 g (0.018 mol) of p-hydroxyphenethyl alcohol (hereinafter abbreviated as "PHEP": manufactured by Otsuka Chemical Co., Ltd.) and 0.1 g of hydrosulfite were dissolved.
To this, 500 ml of methylene chloride was added, 0.5 g of benzyltriethylammonium chloride (hereinafter abbreviated as "TEBAC") was added while stirring, and 60 g of phosgene was then blown in about 60 minutes while keeping the temperature at 15 to 20 ° C. ..
After the completion of phosgene blowing, add 100 ml of a 5 w / w% sodium hydroxide aqueous solution and stir vigorously to emulsify the reaction solution. After emulsification, add 0.4 ml of triethylamine and stir at 20 to 30 ° C. for about 1 hour. And polymerized.
After completion of the polymerization, the reaction solution was separated into an aqueous phase and an organic phase, the organic phase was neutralized with phosphoric acid, and washing with water was repeated until the conductivity of the washing solution (aqueous phase) became 10 μS / cm or less. The obtained polymer solution was added dropwise to warm water maintained at 60 ° C., and the solvent was evaporated and removed to obtain a white powdery precipitate.
The obtained precipitate was filtered and dried at 105 ° C. for 24 hours to obtain a polymer powder.
The ultimate viscosity of a solution of this polymer using methylene chloride as a solvent at a concentration of 0.5 g / dl at 20 ° C. was 0.55 dl / g. As a result of analyzing the obtained polymer by an infrared absorption spectrum, absorption by a carbonyl group was observed at a position near 1770 cm ^-1 , and absorption by an ether bond was observed at a position near 1240 cm ^-1 , and a polycarbonate resin having a carbonate bond (hereinafter referred to as "" It was confirmed that it was abbreviated as "PC-1").
12 parts by mass of the obtained PC-1 and 88 parts by mass of methyl ethyl ketone were mixed to prepare a coating solution (28 mPa · s). The solubility of the coating solution by visual judgment was determined to be transparent and uniform dissolution with no undissolved residue. A slide glass (76 × 26 × 1.0 mm) was dipped in the coating solution, quickly pulled up, air-dried, and dried at 100 ° C. for 3 hours to obtain a coated slide glass test piece. When the cross-cut method was applied to the test piece in accordance with JIS K5600-5-6, the judgment was 0. When the film thickness of the obtained test piece after cross-cutting was measured, the average film thickness was 21 μm.

Example 2
Except for changing BPC to 60.4 g and PHEP to 2.53 g, and using 2,2-bis (4-hydroxyphenyl) propane (hereinafter abbreviated as "BPA": manufactured by Mitsubishi Chemical Corporation) 40.1 g at the same time. Polymerization was carried out in the same manner as in Example 1 to obtain polycarbonate (extreme viscosity 0.54 dl / g, hereinafter abbreviated as "PC-2"). A coating solution (27 mPa · s) was prepared with 12 parts by mass of the obtained PC-2 and 88 parts by mass of methyl ethyl ketone, and the coating and evaluation were carried out in the same manner as in Example 1.

Example 3
Same as Example 1 except that 1,1-bis (4-hydroxyphenyl) -1-phenylethane (hereinafter abbreviated as "BPAP": manufactured by Honshu Chemical Industry Co., Ltd.) 116 g was used instead of BPC and TEBAC was not used. Polycarbonate (extreme viscosity 0.52 dl / g, hereinafter abbreviated as "PC-3") was obtained. A coating solution (26 mPa · s) was prepared from the obtained PC-3 with 12 parts by mass, 53 parts by mass of tetrahydrofuran, and 35 parts by mass of propyl acetate, and the coating and evaluation were carried out in the same manner as in Example 1.

Example 4
Instead of BPC, use 107.2 g of 1,1-bis (4-hydroxyphenyl) cyclohexane (hereinafter abbreviated as "BPZ": manufactured by Honshu Chemical Industry Co., Ltd.), change PHEP to 1.58 g, and do not use TEBAC. Polymerization was carried out in the same manner as in Example 1 to obtain polycarbonate (extreme viscosity 0.60 dl / g, hereinafter abbreviated as "PC-4"). A coating solution (34 mPa · s) was prepared from the obtained PC-4 with 12 parts by mass, 53 parts by mass of tetrahydrofuran, and 35 parts by mass of propyl acetate, and the coating and evaluation were carried out in the same manner as in Example 1.

Example 5
18:49:32 mass% mixture of bis (4-hydroxyphenyl) methane, bis (2-hydroxyphenyl) methane and 2,4'-dihydroxydiphenylmethane instead of BPC (hereinafter abbreviated as "BPF": Gunei Chemical Industry Co., Ltd. Example using 36 g of BPA and 51 g of BPA, changing to 1.43 g of p-hydroxybenzyl alcohol (hereinafter abbreviated as "PHBA": manufactured by Tokyo Kasei Kogyo Co., Ltd.) instead of PHEP, except that TEBAC was not used. Polycarbonate (extreme viscosity 0.99 dl / g, hereinafter abbreviated as "PC-5") was obtained by carrying out polymerization in the same manner as in 1. A coating solution (320 mPa · s) was prepared with 10 parts by mass of the obtained PC-5 and 90 parts by mass of propyl acetate, and the coating and evaluation were carried out in the same manner as in Example 1.

Example 6
Use 40.4 g of bis (4-hydroxyphenyl) ether (hereinafter abbreviated as "DHPE": manufactured by Tokyo Kasei Kogyo Co., Ltd.) and 53.6 g of BPZ instead of BPC, change to PHBA 1.43 g instead of PHEP, and use TEBAC. Polymerization was carried out in the same manner as in Example 1 except that it was not used, to obtain a polycarbonate (extreme viscosity 1.01 dl / g, hereinafter abbreviated as "PC-6"). A coating solution (16 mPa · s) was prepared from the obtained PC-6 with 5 parts by mass, 57 parts by mass of tetrahydrofuran, and 38 parts by mass of methyl ethyl ketone, and the coating and evaluation were carried out in the same manner as in Example 1.

Comparative Example 1
Same as Example 1 except that BPC was changed to 91.2 g of BPA, 2.67 g of pt-butylphenol (hereinafter abbreviated as "PTBP": manufactured by DIC Corporation) was used instead of PHEP, and TEBAC was not used. Polymerization was carried out to obtain polycarbonate (extreme viscosity 0.39 dl / g, hereinafter abbreviated as "PC-7"). An attempt was made to prepare a coating solution of the obtained PC-7 in the same manner as in Example 1, but it was not soluble in the solvent and could not be coated.

Comparative Example 2
Polymerization was carried out in the same manner as in Example 1 except that PTBP was changed to 2.67 g instead of PHEP to obtain polycarbonate (extreme viscosity 0.39 dl / g, hereinafter abbreviated as "PC-8"). Using the obtained PC-8, a coating solution was prepared in the same manner as in Example 1, and coating and evaluation were performed.

Comparative Example 3
Polymerization was carried out in the same manner as in Example 2 except that PTBP was changed to 2.67 g instead of PHEP to obtain polycarbonate (extreme viscosity 0.38 dl / g, hereinafter abbreviated as "PC-9"). Using the obtained PC-9, a coating solution was prepared in the same manner as in Example 2, and coating and evaluation were performed.

Comparative Example 4
Polymerization was carried out in the same manner as in Example 4 except that PTBP was changed to 2.67 g instead of PHEP to obtain polycarbonate (extreme viscosity 0.35 dl / g, hereinafter abbreviated as "PC-10"). Using the obtained PC-10, a coating solution was prepared in the same manner as in Example 4, and coating and evaluation were performed.

Comparative Example 5
Polymerization was carried out in the same manner as in Example 4 except that PTBP was changed to 1.79 g instead of PHEP to obtain polycarbonate (extreme viscosity 0.57 dl / g, hereinafter abbreviated as "PC-11"). Using the obtained PC-11, a coating solution was prepared in the same manner as in Example 4, and coating and evaluation were performed.

The utilization example of the present invention can be used as a coating solution for protecting an article. In particular, it is suitable for coating in fields where durability in daily life is required, such as IC cards and security cards.

Claims (5)

A polycarbonate resin having at least one selected from the group consisting of the following formulas (4) to (11) in which the following structural formula (1) is bonded to the molecular terminal is 0.1 to 50% by mass , and a non-halogen solvent. Is a coating solution containing
A coating solution in which the non-halogen solvent contains tetrahydrofuran or propyl acetate.

(In the formula (1), R ₁ is an alkylene having 1 to 2 carbon atoms, R ₂ to R ₃ are hydrogens, Z is a single bond, a is an integer of 1, and Y is an ether bond. )

The coating solution according to claim 1 , wherein the polycarbonate resin has an extreme viscosity of 0.3 to 2.0 dl / g. The coating solution according to claim 1 or 2, wherein the non-halogen solvent contains tetrahydrofuran and propyl acetate. A method for forming a film for removing a non-halogen solvent from the coating solution according to any one of claims 1 to 3 . A molded body coated by the method according to claim 4 .