JP5970866B2 - Biomass plastic paint - Google Patents

Description

   The present invention relates to a copolymerized polyester resin containing a diol having a bridged ring structure composed of an aromatic dicarboxylic acid, a dimer acid, and a saturated alicyclic ring at a specific copolymerization ratio, and a resin composition for coatings using the same.

  Up to now, resins using petroleum raw materials have been used in the fields of inks, coating agents, adhesives, etc., but in recent years, the movement to use petroleum alternative raw materials for various purposes in consideration of the environment has been increasing year by year. In response to this trend, a resin made only of biomass-derived raw materials such as polylactic acid, and a resin obtained by copolymerizing biomass raw materials have attracted attention.

  For example, Patent Document 1 discloses that a polyester resin obtained by copolymerizing dimer acid, which is a biomass raw material, is used as an adhesive. Moreover, in patent document 2, the polyester resin which uses isosorbide which is a biomass raw material as a copolymerization component is disclosed. Further, Patent Document 3 discloses a polyester resin having furan carboxylic acid, which is a biomass raw material, as a copolymerization component.

JP 2010-37463 A JP 2010-95696 A JP 2008-291243 A

  However, the polyester resin copolymerized with dimer acid disclosed in Patent Document 1 is practical in terms of moisture and heat resistance, mechanical strength, particularly scratch resistance, when a coating film is formed for coating. It is hard to say that there is. Moreover, the polyester resin which uses isosorbide as a copolymerization component disclosed in Patent Document 2 is generally less reactive than an aliphatic glycol used as a polyester raw material, and has a drawback that it is easily altered during polymerization. is there. Moreover, the polyester resin which uses the furan carboxylic acid currently disclosed by patent document 3 as a copolymerization component has a problem in the stable supply of furan carboxylic acid, and it cannot be said that it is practical at this time.

  The problem of the present invention is that it is amorphous so that it can exhibit a high level of moisture and heat resistance, scratch resistance and adhesion when made into a coating film, despite using readily available biomass raw materials. A polyester resin, and a coating composition and a laminate using the same are provided.

In order to achieve the above-mentioned problems, the present inventors have intensively studied and have proposed the following invention. That is, this invention is the copolymer polyester shown below, the resin composition for coating materials, and a laminated body.
(1) A copolyester resin mainly composed of a dicarboxylic acid component and a glycol component, and when the total polyvalent carboxylic acid component constituting the copolyester is 100 mol%, the dicarboxylic acid component is an aromatic dicarboxylic acid. Copolymer polyester resin containing 50 mol% or more of dimer acid, 5 mol% or more of dimer acid, and 10 to 35 mol% of a diol having a crosslinked ring structure composed of a saturated alicyclic ring as the glycol component.
(2) A diol having a bridged ring structure composed of a saturated alicyclic ring as the glycol component, wherein the dicarboxylic acid component contains 60 to 95 mol% of aromatic dicarboxylic acid and 5 to 30 mol% of dimer acid. Copolyester resin as described in (1) containing 10-30 mol%.
(3) The copolyester resin according to (1) or (2), wherein the glycol component is tricyclodecane dimethanol.
(4) A coating resin composition containing the copolymerized polyester resin according to any one of (1) to (3).
(5) A laminate comprising a layer made of the copolyester resin according to any one of (1) to (3) and a base material made of biomass plastic.
(6) A laminate having a layer made of the copolyester resin according to any one of (1) to (3) and a base material made of biomass plastic in direct contact therewith.

  The copolymerized polyester resin of the present invention specifies a dicarboxylic acid having an aromatic skeleton and a diol having a bridged ring structure composed of a saturated alicyclic ring while using dimer acid, which is an easily available biomass material, as a copolymerization component. By containing in the copolymerization ratio, a coating film excellent in moisture and heat resistance, scratch resistance and adhesion can be easily formed. Moreover, since the copolyester resin of the present invention is excellent in dissolution stability, it is excellent in storage stability in a varnish state.

  Hereinafter, embodiments of the present invention will be described in detail. The copolyester is a polyester having a chemical structure obtained by polycondensation of a carboxylic acid component composed of a divalent or higher polyvalent carboxylic acid compound and an alcohol component composed of a divalent or higher polyhydric alcohol compound. At least one of the polyvalent carboxylic acid compound and the polyhydric alcohol compound is composed of two or more kinds of components. The copolymerized polyester of the present invention is a copolymerized polyester resin mainly composed of a dicarboxylic acid component and a glycol component. Here, mainly means that the total of the dicarboxylic acid component and the glycol component occupies 50 mol% or more on a molar basis with respect to the total of all acid components and all alcohol components constituting the copolymer polyester of the present invention. The total of the dicarboxylic acid component and the glycol component is preferably 70 mol% or more, more preferably 85 mol% or more, further preferably 95 mol% or more, and may be 100 mol%. .

  In the copolymerized polyester resin of the present invention, when the total of all polyvalent carboxylic acid components is 100 mol%, the copolymerization ratio of the aromatic dicarboxylic acid is 50 mol% or more, preferably 60 mol% or more, more preferably Is 80 mol% or more. If the copolymerization ratio of the aromatic dicarboxylic acid is too low, the mechanical strength of the resulting coating film tends to be low and may not be practical. On the other hand, the copolymerization ratio of the aromatic dicarboxylic acid is 95% or less. If the copolymerization ratio of the aromatic dicarboxylic acid is too high, it will be difficult to increase the biomass degree, and it will be difficult to obtain a biomass degree of 25%, which is the standard for the biomass plastic identification display system.

  On the other hand, in the copolymerized polyester resin of the present invention, when the total of all carboxylic acid components is 100 mol%, the copolymerization ratio of the dimer acid is 5 mol% to 30 mol%, more preferably 10 mol% to 20 mol. % Or less. If the copolymerization ratio of the dimer acid is too high, the mechanical strength of the resulting coating film tends to be low and may not be practical. On the other hand, if the copolymerization ratio of dimer acid is too low, it becomes difficult to increase the biomass degree, and it becomes difficult to obtain a biomass degree of 25%, which is the standard of the biomass plastic identification display system.

  The aromatic dicarboxylic acid of the present invention is not particularly limited, and examples thereof include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, and naphthalenedicarboxylic acid, p-oxybenzoic acid, and p- (hydroxyethoxy) benzoic acid. Examples thereof include aromatic oxycarboxylic acids such as acids. The use of terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid is preferred from the viewpoint of the polymerizability of the polyester resin, the solubility in general-purpose solvents and the storage stability.

  In addition, polyvalent carboxylic acid components other than the aromatic dicarboxylic acid component and the dimer acid component can be copolymerized to the extent that the performance of the resulting polyester resin is not impaired. For example, saturated aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid and dodecane dicarboxylic acid, unsaturated aliphatic dicarboxylic acids such as fumaric acid, maleic acid and itaconic acid, and unsaturated fats such as tetrahydrophthalic acid Examples thereof include alicyclic dicarboxylic acids such as cyclic dicarboxylic acid, hexahydrophthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid. Further, if necessary, a trivalent or higher polyvalent carboxylic acid compound may be used, and more specifically, a tricarboxylic acid such as trimellitic acid, trimesic acid, pyromellitic acid and / or tetracarboxylic acid may be included. The copolymerization ratio of the trivalent or higher polyvalent carboxylic acid compound is preferably 0.5 mol% or more and 5.0 mol% or less. By copolymerization within this range, the resin skeleton is branched, and the terminal is terminated. Increases and promotes the reaction. If the copolymerization ratio of the trivalent or higher polyvalent carboxylic acid compound is too high, it will gel and the solvent solubility will deteriorate.

The copolyester resin of the present invention is a copolyester resin containing 10 to 35 mol% of a diol having a crosslinked structure composed of saturated alicyclic rings when the total polyhydric alcohol component is 100 mol%.

  The diol having a bridged ring structure composed of saturated alicyclic rings preferably has 5 to 15 carbon atoms constituting the largest ring. Preferable examples of the diol having a bridged ring structure composed of a saturated alicyclic ring include tricyclodecane dimethanol and adamantane diol. By copolymerizing a diol having a bridged ring structure composed of a saturated alicyclic ring, a rigid resin skeleton is formed, and the glass transition temperature of the resin can be increased. As the diol having a bridged ring structure composed of saturated alicyclic rings, those having 6 to 10 carbon atoms constituting the largest ring are particularly preferable, and the heat resistance and scratch resistance of the coating film are particularly excellent. In addition, a diol having a bridged ring structure composed of a saturated alicyclic ring has a higher molecular weight than a short-chain glycol, so that the ester group concentration of the resulting copolyester resin is lowered and the hydrolysis can be suppressed. It is in.

  The lower limit of the copolymerization ratio of the diol having a bridged ring structure composed of saturated alicyclic rings needs to be 10 mol% when the total of all glycolic acid components is 100 mol%, and may be 15 mol%. More preferred. Moreover, the upper limit of the copolymerization ratio of the diol having a bridged ring structure composed of saturated alicyclic rings needs to be 35 mol%, more preferably 30%, and still more preferably 25%. If the copolymerization ratio of the diol having a bridged ring structure composed of saturated alicyclic rings is too low, the heat resistance of the coating film tends to deteriorate and may not be practical. On the other hand, if it is too high, the polymerization reaction takes a long time and the productivity is deteriorated, and the scratch resistance of the coating film may be lowered.

  Moreover, the glycol component which comprises the copolymerization polyester resin of this invention can copolymerize a versatile polyhydric alcohol component other than the diol which has a bridged ring structure which consists of a saturated alicyclic ring. Examples of glycols that can be used include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5- Aliphatic glycols such as pentanediol and 2-butyl-2-ethyl-1,3-propanediol, oligoalkylene glycols such as diethylene glycol, triethylene glycol and dipropylene glycol, 1,2-cyclohexanedimethanol, 1,3- Examples include alicyclic glycols such as cyclohexanedimethanol and 1,4-cyclohexanedimethanol, and polyalkylene ether glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. In addition, ethylene oxide adduct and propylene oxide adduct of bisphenol A, ethylene oxide adduct and propylene oxide adduct of hydrogenated bisphenol A, and the like can also be used. However, when an aliphatic glycol having 4 or more carbon atoms in the main chain is copolymerized, there is a strong tendency to lower the glass transition temperature of the resulting copolymerized polyester resin, so the copolymerization ratio should be kept low when used as a copolymerization component. It is more preferable that it is not used as a copolymerization component. Among these, alicyclic glycols such as ethylene glycol, neopentyl glycol, 2-butyl-2-ethyl-1,3-propanediol, and 1,4-cyclohexanedimethanol are soluble and storage stable in general-purpose solvents. It is preferable for use from the viewpoint of productivity.

  In addition to these, a trihydric or higher polyhydric alcohol compound may be used if necessary. Specifically, a small amount of triol or tetraol such as trimethylolethane, trimethylolpropane, glycerin, pentaerythritol may be contained. The copolymerization ratio of the trihydric or higher polyhydric alcohol compound is preferably 0.5 mol% or more and 10.0 mol% or less. By copolymerization within this range, the resin skeleton is branched and the terminal is Increases and promotes the reaction. If the copolymerization ratio of the trihydric or higher polyhydric alcohol compound is too high, it will gel and the solvent solubility will deteriorate.

  When the copolymerized polyester resin of the present invention is used as a binder component for paints, it needs to be amorphous. When the resin is crystalline, a uniform coating cannot be obtained. The term “amorphous” as used in the present invention means that the temperature is raised from −100 ° C. to 300 ° C. at 20 ° C./min using a differential scanning calorimeter (DSC), and then to −100 ° C. at 50 ° C./min. The temperature does not show a melting peak in the two temperature raising processes in which the temperature is lowered and subsequently raised from −100 ° C. to 300 ° C. at 20 ° C./min.

  The molecular weight of the copolyester resin of the present invention is not particularly limited, but if it is too low, the scratch resistance tends to decrease, and conversely if too high, the viscosity of the paint may become high and handling may be difficult. It is more preferable that it is 8000 or more and 15000 or less.

  When the copolymerized polyester resin used in the present invention is used as a binder component for paint, the glass transition temperature is preferably 10 ° C. or higher. More preferably, it is 15 ° C. or higher. If the glass transition temperature of the polyester resin is too low, the hardness and scratch resistance of the coating film may be lowered, which is difficult to say practical.

  If the molecular weight of the copolyester resin used in the present invention is too low, the scratch resistance tends to decrease, and conversely, if it is too high, the viscosity of the paint may become too high and handling may be difficult. 8000 to 15000 is preferable.

  As a method for producing the copolyester resin of the present invention, a known method can be employed. For example, after mixing said dicarboxylic acid component and glycol component and making it esterify (transesterification) reaction at 150-250 degreeC, the method of performing polycondensation reaction at 230-300 degreeC, decompressing is mentioned. In addition, you may use alkylester and an acid chloride as said dicarboxylic acid component. At that time, a hindered phenol compound and / or a hindered amine compound may be added as a heat stabilizer.

  The copolyester resin of the present invention may be able to improve the adhesion to the substrate by introducing a polar group as a substituent for the resin side chain or the resin main chain. Examples of the polar group having such an action include a sulfonic acid group, a carboxyl group, a phosphoric acid group, and metal salts thereof, but a sulfonic acid metal base and a carboxyl group are more preferable, and the heat and heat resistance of the resin is taken into consideration. In this case, a carboxyl group is most preferable. Moreover, these polar groups may be used alone or in combination as required.

  The method for introducing a carboxyl group into the copolymerized polyester resin of the present invention is not particularly limited. However, after polymerizing the polyester resin, an acid anhydride is added under normal pressure and a nitrogen atmosphere to carry out an addition reaction. There is a method of introducing a carboxyl group into a polyester resin by introducing an anhydride and then increasing the molecular weight by a polycondensation reaction under reduced pressure. The former method is preferable because the target acid value is easily obtained. Suitable acid anhydrides for these reactions include trimellitic anhydride, phthalic anhydride, pyromellitic anhydride, succinic anhydride, maleic anhydride, 1,8-naphthalic anhydride, -1,2-cyclohexane anhydride. Dicarboxylic acid, cyclohexane-1,2,3,4-tetracarboxylic acid-3,4-anhydride, ethylene glycol bisanhydro trimellitate, 5- (2,5-dioxotetrahydro-3-furanyl) -3 -Methyl-3-cyclohexene-1,2-dicarboxylic anhydride, naphthalene-1,8: 4,5-tetracarboxylic dianhydride, and the like, and one or more of these can be selected Can be used.

  The method for introducing the metal sulfonate group into the copolymerized polyester resin of the present invention is not particularly limited. For example, metal salts such as 5-sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, 5 [4-sulfophenoxy] isophthalic acid, or 2-sulfo-1,4-butanediol, 2,5- By copolymerizing a dicarboxylic acid or glycol containing a sulfonic acid metal base such as a metal salt such as dimethyl-3-sulfo-2,5-hexanediol, the sulfonic acid metal base can be easily introduced.

  The copolyester resin of the present invention can be dissolved in an organic solvent to form a polyester resin varnish. The polyester resin varnish can be used as a coating composition by itself or in combination with other components.

  The temperature at which the polyester resin of the present invention is dissolved to obtain a polyester resin varnish is most preferably 70 to 100 ° C. If the melting temperature is too low, the molecular chains of the amorphous polyester resin cannot be sufficiently entangled, and the dissolution may be insufficient. Moreover, when melt | dissolution temperature is too high, it is because the possibility of causing deterioration of a polyester resin increases.

  Examples of the organic solvent include methyl ethyl ketone, toluene, cyclohexanone, dimethylacetamide, dimethylformamide, N-methylpyrrolidone, tetrahydrofuran, 1,4-dioxane, 1,3-dioxane, 1,3-dioxolane, 1,2-hexanediol, ethyl Examples thereof include carbitol butyl carbitol, propylene glycol monopropyl ether, propylene glycol monobutyl ether, triethylene glycol monobutyl ether and the like. Of these, methyl ethyl ketone, toluene, cyclohexanone, and the like are preferable in terms of resin solubility.

  As the organic solvent used in the present invention, an organic solvent which is a poor solvent in which the polyester resin does not dissolve or swell can be used as long as the performance of the present invention is not impaired. Here, it is preferable to use the organic solvent which becomes a poor solvent in the range of 0 to 70% by mass ratio with respect to the organic solvent in which the polyester resin can be dissolved or swollen. More preferably, it is 5 to 50%. If a poor solvent exceeding 70% is used, the resin may aggregate and settle.

  The organic solvent used in the present invention may be mixed with several kinds of solvents as necessary.

  The polyester resin varnish of the present invention is preferably prepared at a resin solid content concentration of 5 to 45% by mass. More preferably, it is 10-40 mass%, More preferably, it is 15-35 mass%, Most preferably, it is the range of 20-30 mass%. When the resin solid content concentration is too high, the solution viscosity becomes high and workability is greatly reduced. If it is too low, the solution viscosity becomes low and it becomes difficult to control the thickness of the coating film.

  As a method of using the polyester resin varnish of the present invention, a plurality of polyester resins and other film-forming resins may be included as necessary. Although it does not specifically limit as other film forming resin, For example, an acrylic resin, a polyester resin, an alkyd resin, an epoxy resin, a urethane resin etc. can be utilized.

  A curing agent can be blended in the polyester resin varnish of the present invention. As the curing agent, commonly used ones can be used, such as melamine compounds, isocyanate compounds, epoxy compounds, aziridine compounds, carbodiimide compounds, oxazoline compounds, metal ions and the like. Can be mentioned. A melamine compound resin and / or an isocyanate compound is generally used in view of various performances and costs of the obtained coating film.

  The melamine-based curing agent as the curing agent is not particularly limited, and may be either water-soluble or water-insoluble. For example, alkyl etherified melamine resin is preferable, and methoxy group and A melamine resin substituted with a butoxy group is more preferred. As such a melamine resin, those having a methoxy group alone, Sumimar M-30W, Sumimar M-40W, Sumimar M-50W, Sumimar MC-1 (all manufactured by Sumitomo Chemical Co., Ltd.), Cymel 325, Cymel 327 , Cymel 370, My Coat 723, Cymel 202, Cymel 204, Cymel 232, Cymel 235, Cymel 236, Cymel 238, Cymel 254, Cymel 266, Cymel 267 (all of which have both methoxy and butoxy groups Product name, Mitsui Cytec Co., Ltd., My Coat 506 (trade name, Mitsui Cytec Co., Ltd.), Uban 20N60, Uban 20SE (both trade names, Mitsui Chemicals Co., Ltd.), Super Becca Min (Dai Nippon Ink Chemical) Gosha, Ltd.), and the like. These may be used alone or in combination of two or more.

  Examples of the isocyanate compound include aromatic and aliphatic diisocyanates and trivalent or higher polyisocyanates, which may be either low molecular compounds or high molecular compounds. For example, tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate or trimers of these isocyanate compounds, and excess of these isocyanate compounds Amount of low molecular active hydrogen compounds such as ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine or various polyester polyols, polyether polyols, polyamides Obtained by reacting with polymer active hydrogen compounds Terminal isocyanate group-containing compounds to be.

  These isocyanate compounds can be used after being blocked from the viewpoint of storage stability. The blocked isocyanate can be obtained by adding a blocking agent having active hydrogen to a polyisocyanate such as tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, and the blocking agent is dissociated by heating. Thus, an isocyanate group is generated and reacts with the functional group in the resin component to be cured.

  When these hardening | curing agents are contained, it is preferable that the content is 5-50 mass parts with respect to 100 mass parts of resin solid content in a composition. When the lower limit is less than 5 parts by mass, the curability is insufficient, and when the upper limit exceeds 50 parts by mass, the coating film may be too hard.

  By apply | coating a polyester resin varnish to a base material directly or through another layer, the laminated body which has the layer and base material which consist of copolymer polyester resin of this invention can be obtained. The material of the base material is not particularly limited, but using a base material made of biomass plastic is preferable because the biomass degree of the entire laminate can be increased. Here, the biomass plastic means that the weight fraction of the biomass-derived raw material forming the plastic is 25% or more, more preferably 35% or more, still more preferably 50% or more, 90 % Or more is even more preferable. By arranging another appropriate layer between the layer made of the copolymerized polyester resin of the present invention and the base material, the adhesion between both layers is improved, the design property is improved, or some other function is exhibited. May be possible. The layer made of the copolymerized polyester resin of the present invention and the substrate may be directly adjacent to each other without interposing another layer.

When a polyester resin varnish is applied to a substrate to obtain a coating film, the amount of adhesion after drying is not particularly limited, but is 0.01 to 20 g / m ² , more preferably 0.2 to 10 g from the viewpoint of the drying speed. / M ² is desirable. If it is less than 0.01 g / m ² , it is difficult to obtain a uniform coating film, and if it exceeds 20 g / m ² , the drying time becomes long and efficient production becomes difficult.

  Although the conditions at the time of apply | coating a polyester resin varnish to a base material and drying are not specifically limited, It is preferable that it is 40-250 degreeC. If it is less than 40 degreeC, drying time will take time and it is not rational as industrial production. Moreover, there is a possibility that the coating film is not completely dried. On the other hand, if it exceeds 250 ° C., a high-performance drying furnace is required, which is not desirable. The drying method is not limited, but known methods such as a hot air drier, induction heating, near infrared heating, far infrared heating, indirect heating can be applied. If it is applied to a steel plate, a method may be used in which the steel plate is preheated, applied when heated, and dried with residual heat.

  Moreover, the polyester resin varnish of this invention can be apply | coated to a to-be-coated object using a well-known method. The film thickness of the coating film thus obtained is 0.1 to 30 μm.

Next, the present invention will be specifically described using the following examples and comparative examples, but the present invention is not limited thereto. In the examples and comparative examples, “parts” simply means “parts by mass”. The characteristics of the copolyester resin and the coating film were evaluated as follows.

1. Composition of Copolyester Resin Copolyester resin was dissolved in chloroform D and determined by ¹ H-NMR analysis using a nuclear magnetic resonance analyzer (NMR) Gemini-200 manufactured by Varian.

2. Reduced viscosity ηsp / c (unit: dl / g)
0.10 g of the copolyester resin was dissolved in 25 ml of a mixed solvent of phenol / tetrachloroethane (mass ratio 6/4) and measured at 30 ° C. using an Ubbelohde viscosity tube.

3. Number average molecular weight Gel permeation chromatography of copolymer polyester resin using gel permeation chromatograph 150c manufactured by Waters with tetrahydrofuran as eluent, differential refractometer as detector, column temperature 35 ° C., flow rate 1 ml / min. The number average molecular weight in terms of polystyrene was obtained. However, the column used was Showa Denko Co., Ltd. shodex KF-802, KF-804, KF-806 connected in series.

4). Glass transition temperature Using a differential scanning calorimeter (DSC) DSC-220 manufactured by Seiko Instruments Inc., 5 mg of a copolyester resin is sealed in an aluminum press-lid container, and the temperature is from −100 ° C. to 250 ° C., 20 ° C. / The glass transition temperature was defined as the temperature at the intersection of the base line extension below the glass transition temperature and the tangent line indicating the maximum slope between the peak rising portion and the peak apex.

5. Carboxyl group concentration 0.2 g of copolymer polyester resin was precisely weighed and dissolved in 20 ml of chloroform. Subsequently, it titrated with 0.01N potassium hydroxide (ethanol solution) using phenolphthalein as an indicator. The carboxyl group concentration was expressed in terms of potassium hydroxide equivalent (unit: mg KOH / g) per gram of polyester resin.

6). Storage stability A resin varnish P prepared by dissolving a copolymer polyester resin in toluene in a 140 ml glass bottle and adjusting the solid content concentration (hereinafter sometimes abbreviated as NV) to 30% by weight was prepared. The resin varnish was left still in a 40 ° C. incubator in a sealed state, and the state after 3 months and 6 months was visually observed. The case where the turbidity of the varnish and / or sedimentation occurred at the time of dissolution was x, the case where turbidity of the varnish and / or sedimentation was not observed at the time of dissolution but was observed after 3 months, and the case where varnish was observed after 3 months. The case where turbidity and / or sedimentation separation was not observed but was observed after 6 months was indicated as ◯, and the case where neither varnish turbidity nor sedimentation was observed after storage for 6 months was indicated as ◎.

7). Moist heat resistance Using the same 30 wt% resin varnish P used in the storage stability test, 5 parts by weight of coronate HX (made by Nippon Polyurethane Industry Co., Ltd.) with 100 parts by weight of an organic tin catalyst 0.01 parts by mass of a certain KS1260 (manufactured by Kyodo Pharmaceutical Co., Ltd.) was added to obtain a coating liquid Q. This coating solution Q is applied to the corona surface of a biaxially stretched polyester sheet (Toyobo Co., Ltd., Toyobo Ester Co., Ltd., thickness 50 μm) with a hand coater, and then dried at 80 ° C. for 30 minutes to give a coating film of about 20 μm A laminated body having was obtained. The laminate was allowed to stand for 3 days in an environment of 25 ° C. and cured to obtain a cured coating film R. The cured coating film R was allowed to stand in a wet heat environment of 60 ° C. and 95%, and the gel fraction of the cured coating film was measured after 3 weeks. The gel fraction of the cured coating film was determined by the following method. The laminate was cut into 2.5 cm × 10 cm (mass: W1), immersed in a solution of methyl ethyl ketone / toluene = 1/1 (weight ratio) for 1 hour, and then dried in a constant temperature bath at 100 ° C. for 1 hour (mass: W2). Thereafter, the remaining coating film portion was scraped off to obtain only a polyester sheet (mass: W3). The gel fraction was calculated according to the following formula (1).
Gel fraction (%) = {(W2-W3) / (W1-W3)} × 100 (1)
Gels with a gel fraction of 80% or more are marked with ◎, those with less than 80% and 60% or more are marked with ○, those with less than 60% and 1% or more are marked with Δ, and those with less than 1% are marked with ×.

8). Scratch resistance Scratch resistance was evaluated by pencil hardness. A cured coating film R was prepared in the same manner as in the wet heat resistance test, and a pencil hardness test was performed according to JIS K-5600-5-4. Pencil hardness B or higher is indicated by ◎, 2B to 3B is indicated by ○, 4B or lower is indicated by Δ, and those that cannot be measured are indicated by ×.

9. Adhesion The coating liquid Q produced by the same method as in the heat and moisture resistance test was applied to the non-corona surface of a nylon film (Toyobo Harden N1100 manufactured by Toyobo Co., Ltd., thickness 15 μm) with a hand coater, and a vacuum dryer was used. The laminate having a cured coating film S of about 20 μm was obtained by drying at room temperature for 1 hour. This laminate and the above nylon film were laminated at a roll temperature of 150 ° C., a pressure of 3 N, and a speed of 1 m / min to obtain a peel test sample in which the cured coating film S was sandwiched between the nylon films. This peel test sample was cut to a width of 1 cm and evaluated by a T-type peel test using Tensilon (manufactured by Toyo Baldwin, Tensilon UTM IV type) at a tensile speed of 50 mm / min. The measurement temperature at this time was 20 ° C. A tensile strength of 0.6 kg / cm or more was indicated as “◎”, less than 0.6 kg / cm of 0.4 kg / cm or more as “◯”, and less than 0.4 kg / cm as “Δ”.

10. Biomass degree Generally, the biomass degree of resin is defined as follows.
Biomass degree (% by weight) = (resin content of biomass-derived raw material) / (dry weight of entire resin) × 100
Of the raw materials used in the examples and comparative examples of the present invention, sebacic acid and dimer acid are biomass-derived raw materials, and other components are not biomass-derived raw materials, and the polyester resin composition determined by ¹ H-NMR From this, the degree of biomass was calculated.

Example 1
In a reaction vessel equipped with a stirrer, a condenser and a thermometer, 243.6 g (1.47 mol) terephthalic acid, 243.6 g (1.47 mol) isophthalic acid, 255.3 g (0.44 mol) dimer acid, Mellitic acid 6.6 g (0.34 mol) ethylene glycol 228.6 g (3.68 mol), neopentyl glycol 255.7 g (2.46 mol) tricyclodecane dimethanol 134.1 g (0.68 mol), 0.35 g of tetrabutyl titanate was charged as a catalyst, the pressure inside the can was controlled to 0.25 MPa, the temperature was gradually raised while stirring from 180 ° C. to 240 ° C., and an esterification reaction was performed for 100 minutes to obtain an oligomer mixture. Thereafter, the pressure in the reaction system is gradually reduced to 13.3 Pa (0.1 Torr), a polyester polycondensation reaction is performed at 225 ° C. for 60 minutes, the internal pressure of the can is returned to normal pressure, and anhydrous trimellit at 220 ° C. 6.6 g (0.34 mol) of acid was added and stirred for 30 minutes to obtain polyester resin A. The physical properties and characteristics of the polyester resin A are shown in Table 1.

Examples 2-6, Comparative Examples 1-3
Polyester resins B to I shown in Table 1 were obtained in the same manner as in Example 1, except that the types and ratios of the raw materials were changed. Table 1 shows the physical properties and characteristics of polyester resins B to I.

2,6-NDC: 2,6-naphthalenedicarboxylic acid residue 1,4-NDC: 1,4-naphthalenedicarboxylic acid residue DA: Dimer acid residue TMA: Trimellitic acid residue TPA: Terephthalic acid residue IPA : Isophthalic acid residue SA: Sebacic acid residue EG: Ethylene glycol residue TCD-DM: Tricyclodecane dimethanol residue NPG: Neopentyl glycol residue 1,3-PD: 1,3-propanediol residue DMH : 2-butyl-2-ethyl-1,3-propanediol residue

  In Examples 1 to 6, the obtained polyester resin was dissolved in toluene. Further, the heat and heat resistance, hardness, and adhesion to a substrate made of biomass plastic were good.

  The polyester resin G used in Comparative Example 1 is a resin having a high degree of biomass and a Tg in a range that seems to be suitable for coatings, but the obtained coating film has moisture and heat resistance, scratch resistance, and adhesion to a substrate. It was inferior in nature. In particular, the scratch resistance was greatly inferior. It is considered that the polyester resin G of Comparative Example 1 is influenced by a small amount of copolymerized diol having a bridged ring structure.

  The polyester resin H used in Comparative Example 2 is a resin having a high degree of biomass and showing a Tg in a range that seems to be suitable for paints, but the obtained coating film has moisture and heat resistance, scratch resistance, and adhesion to a substrate. It was inferior in nature. In particular, the heat and moisture resistance and scratch resistance were greatly inferior. It is considered that the polyester resin H of Comparative Example 2 has an aromatic dicarboxylic acid copolymerization ratio of less than 50% and a large amount of copolymerization of a diol having a crosslinked ring structure composed of saturated alicyclic rings.

  Polyester resin I used in Comparative Example 3 is a resin having a slightly low biomass degree and Tg in a range that seems to be suitable for paints, but storage stability in resin varnish, moisture and heat resistance of the obtained coating film, scratch resistance It was inferior in adhesion and adhesion to the substrate, and the results were poor overall. Although the dimer acid is copolymerized in the polyester resin I of the comparative example 3, it is thought that the low copolymerization ratio has influenced.

  As is clear from Examples 1 to 6 and Comparative Examples 1 to 3, a polyester resin containing an aromatic dicarboxylic acid, a dimer acid, and a diol having a bridged ring structure composed of a saturated alicyclic ring at a constant copolymerization ratio. It can be seen that a resin having good heat-and-moisture resistance, hardness, and adhesiveness with a base material made of biomass plastic can be obtained.

  When the resin of the present invention is used as a binder component of a paint, it is excellent in the heat and humidity resistance, hardness, and adhesion of the coating film and is industrially useful despite using a biomass raw material.

Claims (6)

A copolymerized polyester resin mainly composed of a dicarboxylic acid component and a glycol component, when the total dicarboxylic acid component constituting the copolyester is 100 mole%, of terephthalic acid, the total amount of isophthalic acid and orthophthalic acid 50 10% to 35% by mole of a diol having a bridged ring structure composed of saturated alicyclic rings when the content of the dimer acid is 5% by mole or more and the total glycol component is 100% by mole as the glycol component. Contains copolyester resin. When the dicarboxylic acid component is 100 mol% of all dicarboxylic acid components, the total amount of terephthalic acid, isophthalic acid and orthophthalic acid is 60 to 95 mol%, and dimer acid is 5 to 30 mol%, The copolymer polyester resin according to claim 1, comprising 10 to 30 mol% of a diol having a bridged ring structure composed of saturated alicyclic rings when the total glycol component is 100 mol% as the glycol component .   The copolyester resin according to claim 1 or 2, wherein the glycol component is tricyclodecane dimethanol.   The resin composition for coating materials containing the copolyester resin in any one of Claims 1-3.   The laminated body which has the layer which consists of a copolymer polyester resin in any one of Claims 1-3, and the base material which consists of biomass plastics.   The laminated body which has a layer which consists of a copolymer polyester resin in any one of Claims 1-3, and a base material which consists of biomass plastics which contact this directly.