Method for producing aliphatic polyester resin colored article, coloring composition for aliphatic polyester resin, and aliphatic polyester resin colored article

Abstract

To provide a method for producing an aliphatic polyester resin colored article which is easy to decolor and decompose a coloring material in processes of disposal and recycling, an aliphatic polyester resin colored article, and a coloring composition for an aliphatic polyester resin.SOLUTION: A method for producing an aliphatic polyester resin colored article includes a process of coloring an aliphatic polyester resin (a) having a constitutional unit derived from a 3-6C aliphatic carboxylic acid by using a coloring composition for an aliphatic polyester resin, wherein the coloring composition for the aliphatic polyester resin contains a coloring material (b), and the coloring material (b) has a reduction rate of an integrated value of absorbances in a visible light region before and after leaving a coloring material aqueous solution obtained by dissolving the coloring material (b) in water and an organic solvent at 70°C for 350 hours of 50% or more.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for producing a colored aliphatic polyester resin, a coloring composition for an aliphatic polyester resin, and a colored aliphatic polyester resin.

Background Art

[0002] In recent years, many environmentally friendly materials have been developed. Among them, applications to resin materials and fibers of aliphatic polyesters derived from biomass resources typified by polylactic acid (PLA) have been actively studied. Since aliphatic polyesters derived from biomass resources often have biodegradability, they have been utilized focusing on such characteristics. Generally, it is difficult to color polyesters with naturally occurring highly hydrophilic dyes, and they are often colored with highly hydrophobic disperse dyes or pigments obtained by chemical synthesis. However, since disperse dyes and pigments hardly consider environmental suitability such as degradability in the biodegradation process and decolorability in recycling, coloring aliphatic polyesters poses a problem of impairing environmental suitability.

[0003] Patent Document 1 describes dyes suitable for polylactic acid fibers, which are typical aliphatic polyester fibers, and methods for improving the light resistance and color development of dyed polylactic acid fibers. However, Patent Document 1 does not mention environmental suitability such as the degradability and decolorability of colorants. Patent Document 2 discloses a highly safe resin colored product obtained by coloring a biodegradable aliphatic polyester with a natural pigment. However, applicable pigments are very limited, and there are problems in the reproducible color gamut, color density, and fastness of the colored product compared to general disperse dyes.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a method for producing a colored product of an aliphatic polyester resin in which decolorization and decomposition of a coloring material are easy in the process of disposal or recycling, a coloring composition for an aliphatic polyester resin, and a colored product of an aliphatic polyester resin.

Means for Solving the Problems

[0006] As a result of intensive studies to solve the above problems, the present inventors have found that a colored product of an aliphatic polyester resin colored with a coloring material that exhibits decomposability under high-temperature environments and in a dissolved state undergoes extremely rapid decomposition of the coloring material simultaneously during the decomposition treatment under high-temperature and high-humidity conditions such as compost, and thus have completed the present invention.

[0007] That is, the present invention relates to the following 1) to 8). 1) A method for producing a colored product of an aliphatic polyester resin, comprising a step of coloring an aliphatic polyester resin (a) having a structural unit derived from an aliphatic carboxylic acid having 3 to 6 carbon atoms with a coloring composition for an aliphatic polyester resin, wherein the coloring composition for an aliphatic polyester resin contains a coloring material (b), and the coloring material (b) has a reduction rate of the integrated value of absorbance in the visible light region of 50% or more before and after leaving a colored material aqueous solution in which the coloring material (b) is dissolved in water and an organic solvent at 70 ° C. for 350 hours. 2) The production method according to 1), wherein the aliphatic polyester resin (a) has biodegradability in a high-temperature and high-humidity environment. 3) The production method according to 1) or 2), wherein the coloring material (b) has a structure represented by the following formula (I) or formula (II).

Chemical formula

[0008] The present invention can provide a method for producing a colored product of an aliphatic polyester resin, a coloring composition for an aliphatic polyester resin, and a colored product of an aliphatic polyester resin, in which decolorization and decomposition of the coloring material are easy during the processes of waste disposal and recycling. [Modes for Carrying Out the Invention]

[0009] Hereinafter, the present invention will be described in detail. It should be noted that the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist thereof. In the specification and claims of the present application, unless otherwise specified, "parts" and "%" including examples, etc. are all described on a mass basis.

[0010] The present invention is a method for producing a colored product of an aliphatic polyester resin, which comprises a step of coloring an aliphatic polyester resin (a) having a structural unit derived from an aliphatic carboxylic acid having 3 to 6 carbon atoms with a coloring composition for an aliphatic polyester resin.

[0011] In the step of coloring the aliphatic polyester resin (a), a coloring composition for an aliphatic polyester resin (hereinafter, also simply referred to as "coloring composition") containing one or more colorants (b) is used.

[0012] [Aliphatic polyester resin (a)] The aliphatic polyester resin (a) has one or more structural units derived from an aliphatic carboxylic acid having 3 to 6 carbon atoms. By containing a carboxylic acid having 3 to 6 carbon atoms as a structural unit, hydrolysis of the polyester resin proceeds in a high-temperature and high-humidity environment. Along with this, the colorant attached or encapsulated in the resin is also liable to undergo hydrolysis, thereby improving the discoloration resistance of the resin-colored product.

[0013] The structural unit derived from a carboxylic acid having 3 to 6 carbon atoms preferably includes either or both of an aliphatic hydroxycarboxylic acid having 3 to 6 carbon atoms and an aliphatic dicarboxylic acid having 3 to 6 carbon atoms.

[0014] Examples of the aliphatic hydroxycarboxylic acids having 3 to 6 carbon atoms include, but are not limited to, aliphatic carboxylic acids capable of condensation polymerization. Representative examples include lactic acid, 3-hydroxypropionic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 2-hydroxypentanoic acid, 3-hydroxypentanoic acid, 4-hydroxypentanoic acid, 5-hydroxypentanoic acid, 2-hydroxyhexanoic acid, 3-hydroxyhexanoic acid, 4-hydroxyhexanoic acid, 5-hydroxyhexanoic acid, and 6-hydroxyhexanoic acid.

[0015] Examples of the aliphatic dicarboxylic acids having 3 to 6 carbon atoms include, but are not limited to, aliphatic dicarboxylic acids capable of condensation polymerization with glycols. Representative examples include malonic acid, succinic acid, glutaric acid, and adipic acid.

[0016] The aliphatic polyester resin (a) can contain structural units derived from aliphatic carboxylic acids other than aliphatic carboxylic acids having 3 to 6 carbon atoms and glycols in the polymer structure. The content of the structural units derived from aliphatic carboxylic acids having 3 to 6 carbon atoms in the polymer is preferably 60% to 100%. When the structural units derived from aliphatic carboxylic acids having 3 to 6 carbon atoms are hydroxycarboxylic acids, the content is preferably 60% to 100%, more preferably 70% to 100%, still more preferably 80% to 100%, and particularly preferably 90% to 100%. When the structural units derived from aliphatic carboxylic acids having 3 to 6 carbon atoms are dicarboxylic acids, the total content with glycols is preferably 60% to 100%, more preferably 70% to 100%, still more preferably 80% to 100%, and particularly preferably 90% to 100%. By setting the content of the structural units derived from aliphatic carboxylic acids within the above range, the decoloring property of the colored polyester resin under high temperature and high humidity is improved.

[0017] The aliphatic polyester resin (a) may contain, as other constituent units, aliphatic carboxylic acids other than aliphatic carboxylic acids having 3 to 6 carbon atoms, glycols, aromatic carboxylic acids such as terephthalic acid, etc. Since the higher the content rate of constituent units with high hydrophobicity such as aromatic carboxylic acids, the more the hydrolysis of the polyester in a high-temperature and high-humidity environment is inhibited, the content rate of aromatic carboxylic acids in the polymer is preferably 0% to 40%, more preferably 0% to 30%, still more preferably 0% to 20%, and particularly preferably 0% to 10%.

[0018] The aliphatic polyester resin (a) may be chemically synthesized by a known synthesis method or may be biosynthesized by microorganisms. Further, as commercially available products, for example, polylactic acid resin "Terramac" (registered trademark) manufactured by Unitika Ltd.; "Lacea" manufactured by Mitsui Chemicals, Inc.; "Ingeo" (registered trademark) manufactured by NatureWorks LLC; polybutylene succinate (PBS) resin, polybutylene succinate adipate (PBSA) resin, "BioPBS (Bio-PBS)" (registered trademark) manufactured by Mitsubishi Chemical Corporation; polybutylene adipate terephthalate (PBAT) - based resin "Ecoflex" (registered trademark) manufactured by BASF SE; and polyhydroxyalkanoate (PHA) - based resin "Green Planet" (registered trademark) manufactured by Kaneka Corporation, etc. can be mentioned.

[0019] (Under high-temperature and high-humidity environment) In the specification and claims of the present application, "under high-temperature and high-humidity environment" refers to an environment conforming to the composting conditions of JIS K 6953-1:2011. In this environment, the aliphatic polyester resin (a) becomes biodegradable or hydrolyzable. When the decomposition of the aliphatic polyester resin (a) does not proceed, the temperature and humidity can be adjusted as appropriate. The colored product of the aliphatic polyester resin gradually fades under high temperature and high humidity, but the fading property of the coloring material is further improved by standing in compost.

[0020] (Biodegradability) The aliphatic polyester resin (a) can preferably be used as a resin that is determined to have biodegradability in a test method according to the biodegradability test (JIS K 6953-1:2011) for plastic composts.

[0021] [Coloring composition] The coloring composition contains one or more coloring materials (b). The coloring material (b) is characterized in that an aqueous solution of the coloring material obtained by dissolving the coloring material (b) in water and an organic solvent has a decoloring property. The decoloring property in the aqueous solution of the coloring material means that when exposed to a high-temperature environment for 350 hours, the reduction rate (hereinafter abbreviated as "reduction rate of absorbance") of the integrated value in the visible light region (380 nm to 780 nm) of the absorbance before and after is 50% or more.

[0022] The high-temperature environment for evaluating the decoloring property of the aqueous solution of the coloring material refers to placing it in a thermostatic bath maintained at 70°C. Since 58°C ± 2°C is the test temperature in the biodegradability test (JIS K 6953-1:2011) of biodegradable plastics using compost, the temperature for evaluating the decoloring property of the aqueous solution of the coloring material is preferably 60°C or higher, and by setting it to 70°C, the presence or absence of the decoloring property of the aqueous solution of the coloring material can be confirmed more simply in a shorter period.

[0023] Considering that the test period for determining the decoloring property of the coloring material in the solution is often about several weeks to several months for the biodegradability of biodegradable plastics in compost, it is preferably about one month. In the examples of the present invention, since it was possible to determine the presence or absence of the decoloring property of the coloring material within 2 weeks (350 hours) in a 70°C environment, the presence or absence of the decoloring property of the coloring material was determined based on the reduction rate of the absorbance of the coloring material at 350 hours in a 70°C environment.

[0024] The higher the reduction rate of the absorbance of the aqueous solution of the coloring material at high temperature, the better. The reduction rate of the absorbance at 350 hours in a 70°C environment is 50% to 100%, preferably 75% to 100%, more preferably 80% or more. The higher the reduction rate of the absorbance of the aqueous solution of the coloring material, the better the decoloring property of the aliphatic polyester resin colored product colored with the coloring composition containing the coloring material in a high-temperature and high-humidity environment.

[0025] The organic solvent to be contained in the coloring material aqueous solution is an organic solvent that can dissolve the coloring material and water, and is any one of dimethylformamide (DMF), dimethyl sulfoxide (DMSO), and pyridine. The content of the organic solvent in the coloring material aqueous solution is 45% - 55%.

[0026] As the water to be contained in the coloring material aqueous solution, there is no particular limitation, and pure water such as ion-exchanged water, ultrafiltration water, reverse osmosis permeated water, distilled water, or ultrapure water can be used. The content of water in the coloring material solution is 45% - 55%.

[0027] The content of the coloring material (b) in the coloring material aqueous solution is not particularly limited as long as it is a concentration at which the absorbance spectrum of the coloring material aqueous solution can be measured using a spectrophotometer, but it is set to 5 - 10 mg / L.

[0028] The acidity of the coloring material aqueous solution is pH 5.0 - 8.0. The coloring material aqueous solution may contain a pH adjuster. When the pH of the coloring material aqueous solution shows good decoloring property at any value within the above range, the aliphatic polyester resin colored product colored using the coloring composition containing the coloring material has extremely good decoloring property in a high-temperature and high-humidity environment.

[0029] The coloring material (b) is not particularly limited as long as the coloring material aqueous solution shows decoloring property in a high-temperature environment. However, since it is for coloring polyester resin, disperse dyes, oil-soluble dyes, and organic pigments are particularly preferred, and disperse dyes are more preferred from the viewpoint of solubility.

[0030] Typical disperse dyes include, for example, C.I. Disperse Yellow 1, 3, 4, 5, 7, 9, 13, 23, 24, 30, 33, 34, 42, 44, 49, 50, 51, 54, 56, 58, 60, 61, 63, 64, 66, 68, 71, 74, 76, 79, 82, 83, 85, 86, 88, 90, 91, 93, 98, 99, 100, 104, 108, 114, 116, 118, 119, 122, 124, 126, 135, 140, 141, 149, 154, 160, 162, 163, 164, 165, 179, 180, 182, 183, 184, 186, 192, 198, 199, 201, 202, 204, 210, 211, 215, 216, 218, 224, 227, 231, 232, 242; C.I. Disperse Orange 1, 3, 5, 7, 11, 13, 17, 20, 21, 25, 29, 30, 31, 32, 33, 37, 38, 42, 43, 44, 45, 46, 47, 48, 49, 50, 53, 54, 55, 56, 57, 58, 59, 60, 61, 66, 71, 73, 76, 78, 80, 89, 90, 91, 93, 96, 97, 119, 127, 130, 139, 142, 149, 155, 288; C.I. Disperse Red 1, 4, 5, 7, 11, 12, 13, 15, 17, 27, 43, 44, 50, 52, 53, 54, 55, 56, 58, 59, 60, 65, 72, 73, 74, 75, 76, 78, 81, 82, 86, 88, 90, 91, 92, 93, 96, 103, 105, 106, 107, 108, 110, 111, 113, 117, 118, 121, 122, 126, 127, 128, 131, 132, 134, 135, 137, 143, 145, 146, 151, 152, 153, 154, 157, 159, 164, 167, 169, 177, 179, 181, 183, 184, 185, 188, 189, 190, 191, 192, 200, 201, 202, 203, 205, 206, 207, 210, 221, 224, 225, 227, 229, 239, 240, 257, 258, 277, 278, 279, 281, 288, 298, 302, 303, 310, 311, 312, 320, 323, 324, 328, 364; C.I.Disperse Violet 1, 4, 8, 23, 26, 27, 28, 31, 33, 35, 36, 38, 40, 43, 46, 48, 50, 51, 52, 56, 57, 59, 61, 63, 69, 77; CI Disperse Green 9; CI Disperse Brown 1, 2, 4, 9, 13, 19; CI Disperse Blue 3, 7, 9, 14, 16, 19, 20, 24, 26, 27, 35, 43, 44, 54, 55, 56, 58, 60, 62, 64, 71, 72, 73, 75, 79, 81, 82, 83, 87, 91, 92, 93, 94, 95, 96, 102, 106, 108, 112, 113 , 115, 118, 120, 122, 125, 128, 130, 139, 141, 142, 143, 146, 148, 149, 153, 154, 158, 165, 167, 171, 173, 174, 176, 181, 183, 185, 186, 187, 189, 197, 198, 200, 201 , 205, 207, 211, 214, 224, 225, 257, 259, 267, 268, 270, 284, 285, 287, 288, 291, 293, 295, 297, 301, 315, 330, 333, 359, 360; CI Disperse Black 1, 3, 10, 24, etc.

[0031] Representative oil-soluble dyes include, for example, CI Solvent Black 3, 7, 27, 29, 34; CI Solvent Yellow 14, 16, 19, 29, 56, 82, 163; CI Solvent Red 1, 3, 8, 18, 24, 27, 43, 51, 72, 73, 132, 218; CI Solvent Violet 3; CI Solvent Blue 2, 5, 11, 70; CI Solvent Green 3, 7; and CI Solvent Orange 2, 60.

[0032] Typical organic pigments include, for example, C.I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 16, 17, 24, 34, 35, 37, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 99, 108, 109, 110, 113, 114, 117, 120, 124, 128, 129, 133, 138, 139, 147, 151, 153, 154, 167, 172, 180; C.I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 40, 41, 42, 48(Ca), 48(Mn), 57(Ca), 57:1, 88, 112, 114, 122, 123, 144, 146, 149, 150, 166, 168, 170, 171, 175, 176, 177, 178, 179, 184, 185, 187, 202, 209, 219, 224, 245; C.I. Pigment Blue 1, 2, 3, 15, 15:1, 15:2, 15:3, 15:4, 16, 18, 22, 25, 60, 65, 66, C.I. Vat Blue 4, 60; C.I. Pigment Violet 19, 23, 32, 33, 36, 38, 43, 50; C.I. Pigment Green 7, 10, C.I. Pigment Brown 3, 5, 25, 26; C.I. Pigment Orange 1, 2, 5, 7, 13, 14, 15, 16, 24, 34, 36, 38, 40, 43, 63, etc.

[0033] The colorant (b) may be a colorant among those listed above, where the aqueous solution of the colorant exhibits decoloring properties under high-temperature environments, or it may be an arbitrarily synthesized colorant not listed above.

[0034] The colorant (b) is not particularly limited as long as it exhibits decoloring properties in the aqueous solution of the colorant. Preferably, it is a pigment having a heterocyclic skeleton, more preferably an azo pigment having a heterocyclic skeleton in the molecule, still more preferably an azo pigment having a monocyclic heterocyclic skeleton, and particularly preferably a monoazo pigment having a monocyclic heterocyclic skeleton. By using a pigment having a heterocyclic skeleton, the hydrolysis of the colorant becomes easier, and it is considered that the decomposability in the solution is improved.

[0035] The "heterocyclic group" has a hetero atom (e.g., nitrogen atom, sulfur atom, oxygen atom) in the ring of its heterocyclic moiety, and may be a saturated ring, an unsaturated ring, a monocyclic ring or a condensed ring, and may be unsubstituted or have a substituent. For example, tetrahydrofuranyl group, dihydrofuranyl group, dihydrofuranyl group, tetrahydropyranyl group, dihydropyranyl group, oxocanyl group, dioxanyl group, tetrahydrothiophenyl group, dithianyl group, pyrrolidinyl group, pyrrolinyl group, tetrahydropyridinyl group, piperazinyl group, homopiperazinyl group, piperidinyl group, pyrrolyl group, furyl group, thiophenyl group, benzopyrrolyl group, benzofuryl group, benzothiophenyl group, pyrazolyl group, isoxazolyl group, isothiazolyl group, indazolyl group, benzoisoxazolyl group, benzoisothiazolyl group, imidazolyl group, oxazolyl group, thiazolyl group, benzimidazolyl group, benzoxazolyl group, benzothiazolyl group, pyridyl group, quinolinyl group, isoquinolinyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, cinnolinyl group, phthalazinyl group, quinazolinyl group, quinoxalinyl group, acridinyl group, phenanthridinyl group, phthalazinyl group, carbazolyl group, uracil group, dithiouracil group, carbolinyl group, purinyl group, thiadiazolyl group, etc. can be mentioned, and these may be unsubstituted or have a substituent.

[0036] Examples of the substituent that the heterocyclic group may have include a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an acyl group, an acyloxy group, an acylamino group, an alkyloxy group, an alkenyloxy group, an alkynyloxy group, an aryloxy group, a heterocyclic oxy group, an alkyloxycarbonyl group, an alkenyloxycarbonyl group, an alkynyloxycarbonyl group, an aryloxycarbonyl group, a heterocyclic oxycarbonyl group, a carbamoyl group, an alkylsulfonyl group, an alkenylsulfonyl group, an alkynylsulfonyl group, an arylsulfonyl group, a heterocyclic sulfonyl group, an alkylsulfonyloxy group, an alkenylsulfonyloxy group, an alkynylsulfonyloxy group, an arylsulfonyloxy group, a heterocyclic sulfonyloxy group, a nitro group, a sulfamoyl group, an alkylsulfonamide group, an alkenylsulfonamide group, an alkynylsulfonamide group, an arylsulfonamide group, a heterocyclic sulfonamide group, an amino group, an alkylamino group, an alkenylamino group, an alkynylamino group, an arylamino group, a heterocyclic amino group, an alkyloxycarbonylamino group, an alkenyloxycarbonylamino group, an alkynyloxycarbonylamino group, an aryloxycarbonylamino group, a heterocyclic oxycarbonylamino group, an alkylsulfinyl group, an alkenylsulfinyl group, an alkynylsulfinyl group, an arylsulfinyl group, an alkylthio group, an alkenylthio group, an alkynylthio group, an arylthio group, a hydroxy group, a cyano group, a sulfo group, a carboxyl group, an alkyloxyamino group, an alkenyloxyamino group, an alkynyloxyamino group, an aryloxyamino group, a carbamoylamino group, a sulfamoylamino group, a sulfamoylcarbamoyl group, a carbamoylsulfamoyl group, a dialkyloxyphosphinyl group, a diallyloxyphosphinyl group, a dialkynyloxyphosphinyl group, and a diaryloxyphosphinyl group, etc.

[0037] Furthermore, the "aryl group" in the present specification may be a monocyclic or fused ring, and may have the above-mentioned substituents which may be unsubstituted or may have a heterocyclic group. When having two or more substituents, those substituents may be the same or different.

[0038] Among the dyes having a heterocyclic skeleton, the dyes represented by the following formula (I) or the following formula (II) are particularly preferred. By using the dye represented by the formula (I) or the formula (II), it is considered that the hydrolyzability in the solution is improved.

[0039]

Chemical formula

[0040]

Chemical formula

[0041] R 1can be selected from an arbitrary substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group, and a heterocyclic group is preferred from the viewpoint of more effectively exerting the effects of the present invention. R 1 is more preferably a heterocyclic group having 1 to 36 carbon atoms, still more preferably a heterocyclic group having 2 to 24 carbon atoms. For example, pyrrolyl group, furyl group, thiophenyl group, benzopyrrolyl group, benzofuryl group, benzothiophenyl group, pyrazolyl group, isoxazolyl group, isothiazolyl group, indazolyl group, benzoisoxazolyl group, benzoisothiazolyl group, imidazolyl group, oxazolyl group, thiazolyl group, benzimidazolyl group, benzoxazolyl group, benzothiazolyl group, pyridyl group, quinolinyl group, isoquinolinyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, cinnolinyl group, phthalazinyl group, quinazolinyl group, quinoxalinyl group, acridinyl group, phenanthridinyl group, phthalazinyl group, carbazolyl group, carbolinyl group, purinyl group, triazolyl group, oxadiazolyl group, thiadiazolyl group are preferred. Among them, 3-pyrazolyl group, 4-pyrazolyl group, 2-imidazolyl group, 4-imidazolyl group, 5-imidazolyl group, 2-oxazolyl group, 2-thiazolyl group, 2-benzimidazolyl group, 2-benzoxazolyl group, 2-benzothiazolyl group, 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, 2-quinolinyl group, 4-quinolinyl group, 1-isoquinolinyl group, 3-isoquinolinyl group, 3-pyridazinyl group, 4-pyridazinyl group, 2-pyrimidinyl group, 4-pyrimidinyl group, 5-pyrimidinyl group, 2-pyrazinyl group, 2-purinyl group, 6-purinyl group, 8-purinyl group, 3-triazolyl group, 5-triazolyl group, 3-oxadiazolyl group, 5-oxadiazolyl group, 3-thiadiazolyl group, 5-thiadiazolyl group and the like are particularly preferred.

[0042] R 1When it is an aryl group or a heterocyclic group having a substituent, it may be substituted with the aforementioned substituents that may be possessed by the heterocyclic group, and when it is substituted with two or more substituents, those substituents may be the same or different. From the viewpoint of more effectively exhibiting the effects of the present invention, the substituents that the aryl group or heterocyclic group may have are preferably the following groups. That is, a halogen atom (for example, fluorine, chlorine, bromine), an alkyl group (preferably a linear, branched, or cyclic alkyl group having 1 to 48 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, t-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, dodecyl, hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, 1-norbornyl, 1-adamantyl), an alkenyl group (preferably an alkenyl group having 2 to 48 carbon atoms, for example, vinyl, aryl, 3-buten-1-yl), an aryl group (preferably an aryl group having 6 to 48 carbon atoms, for example, phenyl, naphthyl), a heterocyclic group (preferably a heterocyclic group having 1 to 32 carbon atoms, for example, 2-thienyl, 4-pyridyl, 2-furyl, 2-pyrimidinyl, 1-pyridyl, 2-benzothiazolyl, 1-imidazolyl, 1-pyrazolyl, benzotriazol-1-yl), a silyl group (preferably a silyl group having 3 to 38 carbon atoms, for example, trimethylsilyl, triethylsilyl, tributylsilyl, t-butyldimethylsilyl, t-hexyldimethylsilyl), a hydroxyl group, a cyano group, a nitro group, an alkoxy group (preferably an alkoxy group having 1 to 48 carbon atoms, for example, methoxy, ethoxy, 1-butoxy, 2-butoxy, isopropoxy, t-butoxy, dodecyloxy, a cycloalkyloxy group, for example, cyclopentyloxy, cyclohexyloxy), an aryloxy group (preferably an aryloxy group having 6 to 48 carbon atoms, for example, phenoxy, 1-naphthoxy), a heterocyclic oxy group (preferably a heterocyclic oxy group having 1 to 32 carbon atoms, for example, 1-phenyltetrazol-5-oxy, 2-tetrahydropyranyloxy), a silyloxy group (preferably a silyloxy group having 1 to 32 carbon atoms, for example, trimethylsilyloxy, t-butyldimethylsilyloxy, diphenylmethylsilyloxy),An acyloxy group (preferably an acyloxy group having 2 to 48 carbon atoms, for example, acetoxy, pivaloyloxy, benzoyloxy, dodecanoyloxy), an alkoxycarbonyloxy group (preferably an alkoxycarbonyloxy group having 2 to 48 carbon atoms, for example, ethoxycarbonyloxy, t-butoxycarbonyloxy, a cycloalkyloxycarbonyloxy group, for example, cyclohexyloxycarbonyloxy), an aryloxycarbonyloxy group (preferably an aryloxycarbonyloxy group having 7 to 32 carbon atoms, for example, phenoxycarbonyloxy), a carbamoyloxy group (preferably a carbamoyloxy group having 1 to 48 carbon atoms, for example, N,N-dimethylcarbamoyloxy, N-butylcarbamoyloxy, N-phenylcarbamoyloxy, N-ethyl-N-phenylcarbamoyloxy), a sulfamoyloxy group (preferably a sulfamoyloxy group having 1 to 32 carbon atoms, for example, N,N-diethylsulfamoyloxy, N-propylsulfamoyloxy), an alkylsulfonyloxy group (preferably an alkylsulfonyloxy group having 1 to 38 carbon atoms, for example, methylsulfonyloxy, hexadecylsulfonyloxy, cyclohexylsulfonyloxy), an arylsulfonyloxy group (preferably an arylsulfonyloxy group having 6 to 32 carbon atoms, for example, phenylsulfonyloxy), an acyl group (preferably an acyl group having 1 to 48 carbon atoms, for example, formyl, acetyl, pivaloyl, benzoyl, tetradecanoyl, cyclohexanoyl), an alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 48 carbon atoms, for example, methoxycarbonyl, ethoxycarbonyl, octadecyloxycarbonyl, cyclohexyloxycarbonyl), an aryloxycarbonyl group (preferably an aryloxycarbonyl group having 7 to 32 carbon atoms, for example, phenoxycarbonyl), a carbamoyl group (preferably a carbamoyl group having 1 to 48 carbon atoms, for example, carbamoyl, N,N-diethylcarbamoyl, N-ethyl-N-octylcarbamoyl, N,N-dibutylcarbamoyl, N-propylcarbamoyl, N-phenylcarbamoyl, N-methyl-N-phenylcarbamoyl, N,N-dicyclohexylcarbamoyl), an amino group (preferably an amino group having 32 or fewer carbon atoms,For example, amino, methylamino, N,N-diethylamino, N,N-dibutylamino, tetradecylamino, 2-ethylhexylamino, cyclohexylamino), anilino group (preferably an anilino group having 6 to 32 carbon atoms, for example, anilino, N-methylanilino), heterocyclic amino group (preferably a heterocyclic amino group having 1 to 32 carbon atoms, for example, 4-pyridylamino), carboxamide group (preferably a carboxamide group having 1 to 32 carbon atoms, for example, acetamide, benzamide, pivaloylamide, cyclohexaneamide, adamantylamino, 2-ethylhexaneamide, provided that perfluoroalkylcarbonylamino group is excluded), ureido group (preferably a ureido group having 1 to 32 carbon atoms, for example, ureido, N,N-dimethylureido, N-phenylureido), imide group (preferably an imide group having 10 or less carbon atoms, for example, N-succinimide, N-phthalimide), alkoxycarbonylamino group (preferably an alkoxycarbonylamino group having 2 to 48 carbon atoms, for example, methoxycarbonylamino, ethoxycarbonylamino, t-butoxycarbonylamino, octadecyloxycarbonylamino, cyclohexyloxycarbonylamino), aryloxycarbonylamino group (preferably an aryloxycarbonylamino group having 7 to 32 carbon atoms, for example, phenoxycarbonylamino), azo group (preferably an azo group having 1 to 32 carbon atoms, for example, phenylazo, 3-pyrazolylazo), alkylthio group (preferably an alkylthio group having 1 to 48 carbon atoms, for example, methylthio, ethylthio, octylthio, cyclohexylthio), arylthio group (preferably an arylthio group having 6 to 48 carbon atoms, for example, phenylthio), heterocyclic thio group (preferably a heterocyclic thio group having 1 to 32 carbon atoms, for example, 2-benzothiazolylthio, 2-pyridylthio, 1-phenyltetrazolylthio), alkylsulfinyl group (preferably an alkylsulfinyl group having 1 to 32 carbon atoms, for example, dodecanesulfinyl), arylsulfinyl group (preferably an arylsulfinyl group having 6 to 32 carbon atoms, for example, phenylsulfinyl), alkylsulfonyl group (preferably an alkylsulfonyl group having 1 to 48 carbon atoms, for example, methylsulfonyl, ethylsulfonyl, propylsulfonyl, butylsulfonyl,(Isopropylsulfonyl, 2-ethylhexylsulfonyl, hexadecylsulfonyl, octylsulfonyl, cyclohexylsulfonyl)aryl sulfonyl group (preferably an aryl sulfonyl group having 6 to 48 carbon atoms, for example, phenylsulfonyl, 1-naphthylsulfonyl), sulfamoyl group (preferably a sulfamoyl group having 32 or less carbon atoms, for example, sulfamoyl, N,N-dipropylsulfamoyl, N-ethyl-N-dodecylsulfamoyl, N-ethyl-N-phenylsulfamoyl, N-cyclohexylsulfamoyl), sulfo group, phosphonyl group (preferably a phosphonyl group having 1 to 32 carbon atoms, for example, phenoxyphosphonyl, octyloxyphosphonyl, phenylphosphonyl), phosphinoylamino group (preferably a phosphinoylamino group having 1 to 32 carbon atoms, for example, diethoxyphosphinoylamino, dioctyloxyphosphinoylamino). When these substituents are further substituable groups, they may be substituted with the above substituents. When substituted with two or more substituents, those substituents may be the same or different.

[0043] R 2 、R 3 、and R 4 represent a hydrogen atom or the same substituents as those listed as substituents that a heterocyclic group may have. R 2 、R 3 、and R 4 When they are substituable groups, they may further have the same substituents as those listed as substituents that a heterocyclic group may have. When having two or more substituents, those substituents may be the same or different. Also, R 2 and R 3 may combine with each other to form a 5-membered, 6-membered, or 7-membered ring. From the viewpoint of more effectively achieving the effects of the present invention, R 2 、R 3 、and R 4preferably represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an acyl group, a nitro group, a cyano group, a carbamoyl group, an alkylsulfonyl group, an arylsulfonyl group, or a sulfamoyl group, more preferably represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkylsulfonyl group, or an arylsulfonyl group. R 2 is more preferably an alkyl group. R 3 is more preferably a cyano group. R 4 is more preferably a hydrogen atom or an alkyl group.

[0044] X 1 represents a substituted or unsubstituted hydroxy group, amino group, or thiol group, and when these have substituents, they have the substituents listed as the substituents that the heterocyclic group may have. X 2 is NR 10 NH, an oxygen atom, or a sulfur atom. R 10 represents the substituents listed as the substituents that the heterocyclic group may have. From the viewpoint of more effectively exhibiting the effects of the present invention, X 1 is a hydroxy group, X 2 is preferably an oxygen atom.

[0045] R in formula (II) 5 and R 7 represent the same as those of the substituents listed as the substituents that may be unsubstituted, a hydrogen atom, or a heterocyclic group may have. R 6 represents the same as those of the substituents that may be a hydrogen atom or a heterocyclic group may have. R 5 R 6 and R 7 When they are substituable groups, they may further have the same substituents as those listed as the substituents that the heterocyclic group may have, and when they have two or more substituents, those substituents may be the same or different. Also, R 5 and R 6 R 6 and R 7may be combined with each other to form a 5-membered, 6-membered, or 7-membered ring. From the point of more effectively achieving the effects of the present invention, R 5 , R 6 , and R 7 preferably represent unsubstituted, a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an acyl group, a nitro group, a cyano group, a carbamoyl group, an alkylthio group, an alkylsulfonyl group, an arylsulfonyl group, or a sulfamoyl group, and more preferably represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkylsulfonyl group, an alkylthio group, or an arylsulfonyl group. R 5 and R 7 are particularly preferably a nitro group or a cyano group, and R7 is particularly preferably a nitro group or a cyano group.

[0046] R in formula (II) 8can be selected from any substituted or unsubstituted aryl group and substituted or unsubstituted heterocyclic group, and the heterocyclic group is more preferred in terms of more effectively achieving the effects of the present invention. When the aryl group and the heterocyclic group are substituable groups, they may be substituted with the same substituents as those listed as the substituents that the heterocyclic group may have, and when substituted with two or more substituents, those substituents may be the same or different. From the point of more effectively achieving the effects of the present invention, the following substituents are preferred. That is, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an acyloxy group, an acylamino group, an alkyloxy group, an alkenyloxy group, an alkynyloxy group, an alkylsulfonyloxy group, an alkenylsulfonyloxy group, an alkynylsulfonyloxy group, an arylsulfonyloxy group, an alkylsulfonamide group, an alkenylsulfonamide group, an alkynylsulfonamide group, an arylsulfonamide group, an amino group, an alkylamino group, an alkenylamino group, an alkynylamino group, an arylamino group, an alkyloxycarbonylamino group, an alkenyloxycarbonylamino group, an alkynyloxycarbonylamino group, an aryloxycarbonylamino group, a heterocyclic oxycarbonylamino group, a hydroxy group, a cyano group, a nitro group, a sulfo group, a carbamoylamino group, a sulfamoylamino group, and a halogen atom are preferred, and an alkyl group, a cyano group, a nitro group, an acylamino group, an alkylsulfonyloxy group, an arylsulfonyloxy group, an alkylamino group, an amino group, a chlorine atom, and a bromine atom are more preferred.

[0047] X in formula (II) 3 and X 4 each independently represents a carbon atom, an oxygen atom, a nitrogen atom, or a sulfur atom. X 3 and X 4 may have the substituents described in the section of "Substituents" when they are substituable. From the point of more effectively achieving the effects of the present invention, X 3 and X 4 are each independently preferably a carbon atom, an oxygen atom, or a nitrogen atom, preferably a carbon atom or a nitrogen atom, X3 is a carbon atom, X 4 is particularly preferably a nitrogen atom.

[0048] The coloring material (b) is not particularly limited as long as it has decoloring properties in an aqueous solution state. In addition to the coloring materials having the structures represented by the formulas (I) and (II), coloring materials having a benzodifuranone skeleton and coloring materials having a benzopyran skeleton also tend to have good decoloring properties and can be preferably used as the coloring material (b).

[0049] Coloring materials having an azobenzene skeleton often do not show decoloring properties in an aqueous solution state. However, when they have strong electron-withdrawing substituents such as cyano groups and nitro groups in the structure and also have hydrolyzable auxochromes such as acylamino groups and acyloxy groups as substituents, they tend to have good decoloring properties and can be preferably used as the coloring material (b).

[0050] The above-mentioned coloring composition may contain coloring materials other than the coloring material (b). However, the content of the coloring material (b) in all the coloring materials is preferably 70 to 100% by mass, more preferably 80 to 100% by mass, and still more preferably 90 to 100% by mass. From the viewpoint of the decomposability of the aliphatic polyester resin coloring, it is extremely preferable that it does not substantially contain coloring materials other than the coloring material (b).

[0051] Various additives such as a dispersant, a dustproof agent, a fungicide, a preservative, a pH adjuster, a chelating agent, a rust inhibitor, an ultraviolet absorber, and an antioxidant can be appropriately added to the above-mentioned coloring composition.

[0052] The coloring composition is not particularly limited as long as it can color the aliphatic polyester resin, but a micronized form is preferable. The micronization of the coloring material can use known wet grinders, wet dispersers, dry grinders, etc.

[0053] When the object to be colored is a fiber, film, or the like made of the above aliphatic polyester resin (a), the form of the coloring composition may be a form other than powder, such as printing ink or inkjet ink. When the object to be colored is a resin molded article and the aliphatic polyester resin is colored and molded using a known resin molding machine or the like, it is preferable to use only the micronized colorant as the coloring composition.

[0054] When the object to be colored is a fibrous aliphatic polyester resin, it is preferable to use the colorant in the form of a dispersion liquid dispersed by a bead mill or the like using a known dispersant so as to be suitable for a known dyeing method for polyester fibers, and a dry powder form obtained by drying it with a known spray dryer or the like is particularly preferable.

[0055] When the object to be colored is in the form of a fabric or film of an aliphatic polyester resin, the coloring composition may be printing ink, inkjet ink, or the like using a dispersion liquid in which the above colorant is dispersed.

[0056] The coloring method of the above aliphatic polyester resin is not particularly limited, but an example is the dyeing of the above fibrous aliphatic polyester resin. By performing a dyeing treatment on a commercially available aliphatic polyester resin fiber using a colorant (disperse dye) wet-dispersed with a dispersant in a known dyeing machine, a fabric of an aliphatic polyester resin fiber colored with the above colorant can be obtained.

[0057] The colored product of the aliphatic polyester resin (a) colored with the colorant (b) undergoes hydrolysis of the polyester resin and decomposes in a high-temperature and high-humidity environment. Along with this, the colorant (b) attached to or encapsulated in the resin is also liable to undergo hydrolysis, thereby improving the color fading property of the resin-colored product.

[0058] The aliphatic polyester resin colored product colored with the coloring material (b) is not particularly limited in its form, but it is preferably in a form in which the aliphatic polyester (a) is biodegradable under a high-temperature and high-humidity environment. From the viewpoint of the progress rate of biodegradation and hydrolysis of the resin (a) of the aliphatic polyester, a form with a large surface area is preferred. Specifically, forms such as films and fibers are preferred. When the resin colored product is a resin molded product or the like with a small surface area, it is preferably subjected to processes such as crushing and pulverization. By undergoing the crushing and pulverization processes, the surface area of the resin colored product is increased, and the decoloration of the coloring material proceeds more rapidly along with the hydrolysis of the aliphatic polyester.

Examples

[0059] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited in any way by the following examples.

[0060] The coloring materials, coloring compositions, and resins used in the examples and comparative examples are as follows. · Coloring material A: Disperse Yellow 114 / Coloring composition A: Dianix Yellow 6GSL (manufactured by DyStar) · Coloring material B: Disperse Yellow 126 / Coloring composition B: Foron Brilliant Yellow S-5GL (manufactured by Clariant) · Coloring material C: Disperse Yellow 211 / Coloring composition C: Terasil Yellow 4G (manufactured by Huntsman) · Coloring material D: Disperse Blue 82 / Coloring composition D: Dispersol Blue GFD (manufactured by ICI) · Coloring material E: Disperse Blue 106 / Coloring composition E: Miketon Discharge Blue R (manufactured by DyStar) · Coloring material F: Disperse Blue 295 / Coloring composition F: Dispersol Blue C-3G (manufactured by ICI) · Coloring material G: Disperse Blue 360 / Coloring composition G: Intratherm Brill. Blue P-1309 (manufactured by Crompton and Knowles) · Colorant H: Disperse Violet 48 / Coloring Composition H: Dianix Violet 4RS (manufactured by Dystar) · Colorant I: Disperse Blue 257 / Coloring Composition I: Kayalon Polyester Blue 3R-SF (manufactured by Nippon Kayaku Co., Ltd.) · Colorant J: Disperse Blue 341 / Coloring Composition J: Kayalon Polyester Blue Green GD-S (manufactured by Nippon Kayaku Co., Ltd.) · Colorant K: Disperse Blue 366 / Coloring Composition K: Kayalon Polyester Blue CR-E (manufactured by Nippon Kayaku Co., Ltd.) · Colorant L: Disperse Yellow 163 / Coloring Composition L: Kayalon Polyester Yellow BRL-S (manufactured by Nippon Kayaku Co., Ltd.) · Colorant M: Solvent Yellow 163 / Coloring Composition M: Kayalon Polyester Yellow KFL (manufactured by Nippon Kayaku Co., Ltd.) · Colorant N: Disperse Orange 30 / Coloring Composition N: Kayalon Polyester Yellow Brown 2RL-S (manufactured by Nippon Kayaku Co., Ltd.) · Colorant O: Disperse Orange 149 / Coloring Composition O: Terasil Golden Yellow 2RS (manufactured by Huntsman) · Colorant P: Disperse Red 50 / Coloring Composition P: Kayalon Poylester Scarlet EF (manufactured by Nippon Kayaku Co., Ltd.) · Colorant Q: Disperse Red 153 / Coloring Composition Q: Kayalon Polyester Light Scarlet G-S 200 (manufactured by Nippon Kayaku Co., Ltd.) · Colorant R: Disperse Red 376 / Coloring Composition R: Terasil Red W-4BS (manufactured by Ciba Specialty Chemicals Inc) · PLA: Polylactic acid · PBAT: Polybutylene adipate terephthalate · PBSA: Polybutylene succinate adipate · PHA: Polyhydroxyalkanoate · PET: Polyethylene terephthalate

[0061] [Example 1] [Preparation of Aqueous Colorant Solution] Weighed 10 mg of coloring composition A, added 250 ml of pure water, and stirred to obtain a dye dilution solution. Added 6 g of dimethylformamide to 6 g of the dye dilution solution to obtain aqueous colorant solution A. Divided aqueous colorant solution A into 5 g portions in glass vials, covered them, and left one of them in a thermostat at 70 °C for 350 hours.

[0062] [Calculation of Decolorization Rate of Aqueous Colorant Solution] Using a spectrophotometer "UV2600i" manufactured by Shimadzu Corporation, the absorbance spectra of each sample were measured at 380 nm to 700 nm. The area values of the spectra of each of the standard aqueous solution and the aqueous solution left in the thermostat at 380 nm to 700 nm were obtained, and the reduction rate of the area values before and after exposure to 70 °C was determined for aqueous colorant solution A. Aref: Area value of the absorbance spectrum at 380 nm to 780 nm in the initial state A: Area value of the absorbance spectrum at 380 nm to 780 nm after 350 hours at 70 °C Decolorization rate of aqueous solution (%) = {1 - (A / Aref)} × 100 Evaluation A: 80% or more and less than 100% Evaluation B: 50% or more and less than 80% Evaluation C: 20% or more and less than 50% Evaluation D: 0% or more and less than 20%

[0063] [Manufacture of PLA Fiber Colored Product] Weighed out the amount of the dyeing product that can obtain a 1% o.w.f. of the coloring composition, added 0.5 g / L of the dispersion leveling agent KP Leveller AL (manufactured by Nippon Kayaku Co., Ltd., an anionic surfactant), and added it to water adjusted to pH 4.5 with acetic acid and sodium acetate, and adjusted the total volume to 100 mL. Immersed 5 g of a white polylactic acid cloth (manufactured by Unitika Ltd.) in this dye bath (dye dispersion solution) and dyed it at 110 °C for 60 minutes. After dyeing, it was washed with water and dried to obtain PLA dyed cloth A.

[0064] <Decomposition treatment under high temperature and high humidity environment> (1) Decomposition treatment of colorimetric standard 30 g of commercially available bark compost was added to a square plastic container (124 mm × 82 mm × 42 mm) with a commercially available lid having steam holes, and after leveling the surface, an uncolored PLA fabric was placed on the compost. Further, 30 g of bark compost was added from above, and after leveling the surface, 2 g of water was sprayed onto the compost surface using a commercially available sprayer. Next, the weight of the container including the contents was measured, and the container was placed in a commercially available high temperature and high humidity machine (「IG400」manufactured by Yamato Scientific Co., Ltd.) maintained at 58 °C and 65% RH. Once every few days, the weight of the container was measured, and the same amount of water as the decreased weight was sprayed onto the compost surface using a commercially available sprayer to keep the moisture content in the container constant. After 30 days had passed, the uncolored PLA dyed fabric was recovered from the compost. (2) Decomposition treatment of samples In the same manner as in (1), instead of the undyed PLA fabric, PLA dyed fabric A was used and the same treatment was performed.

[0065] <Calculation of decolorization rate of dyed fabric> Using a spectrophotometer 「eXact」 manufactured by Xrite, colorimetry of the spectral density in the visible light region (380 nm to 780 nm) of the undyed PLA fabric and PLA dyed fabric A before and after the decomposition treatment was performed. From the results, the decolorization rate of PLA dyed fabric A was determined using the following formula. Xref: Area value of spectral density in the visible light region of the undyed fabric before decomposition treatment Yref: Area value of spectral density in the visible light region of the dyed fabric before decomposition treatment X: Area value of spectral density in the visible light region of the undyed fabric after decomposition treatment Y: Area value of spectral density in the visible light region of the dyed fabric after decomposition treatment Decolorization rate of dyed fabric (%) = {1 - (Y - X) / (Yref - Xref)} × 100 Evaluation A: 80% or more and less than 100% Evaluation B: 50% or more and less than 80% Evaluation C: 25% or more and less than 50% Evaluation D: 0% or more and less than 25%

[0066] [Examples 2 to 11] Except for using coloring compositions B to K instead of coloring composition A, the same procedures as in Example 1 were used to prepare aqueous solutions of colorants B to K and measure the decolorization rates, and to produce PLA-dyed fabrics B to K and determine the decolorization rates before and after the decomposition treatment.

[0067] [Example 12] [Preparation of PBAT resin sheet] (1) Preparation of colorimetric standards 1 g of commercially available PBAT resin pellets (manufactured by Blue Ridge Tunhe Sci. & Tech.) was sandwiched between commercially available cooking sheets, and the resin was preheated and melted using a heat press ("AF-65TEN" manufactured by Asahi Textile Machinery Co., Ltd.) at a set temperature of 200°C and a pressure setting of zero. The resin was then rolled under a pressure of 2.4 MPa and cooled to obtain an uncolored PBAT resin sheet.

[0068] (2) Preparation of colored resin pieces 5 g of the above-mentioned PBAT resin pellets and 10 mg of polyester resin coloring composition C were placed in a commercially available plastic bag, the bag was closed to allow air to enter the bag, and the bag was vigorously shaken until coloring composition C was adsorbed onto the surface of the resin pellets. 1 g of the resin pellets was sandwiched between commercially available cooking sheets, and the resin was preheated and melted using a heat press machine at a set temperature of 200°C with a pressure setting of zero, and then the resin was melted under a pressure of 1.6 N / cm. 2 The resin was rolled under pressure, and cooling and rolling were repeated until the coloring was uniform, to obtain a PBAT resin colored sheet C.

[0069] The decomposition treatment was carried out in a high temperature and high humidity environment in the same manner as in Example 1, except that PBAT resin colored sheet C was used instead of PLA dyed cloth A, and the decolorization rate of PBAT resin colored sheet C was calculated using the following formula. Xref: Area value of spectral density in the visible light region of the uncolored resin sheet before decomposition treatment Yref: Area value of spectral density in the visible light region of the colored resin sheet before decomposition treatment X: Area value of spectral density in the visible light region of the uncolored resin sheet after decomposition treatment Y: Area value of spectral density in the visible light region of the colored resin sheet after decomposition treatment Discoloration rate (%) of the colored resin sheet = {1 - (Y - X) / (Yref - Xref)} × 100 Evaluation A: 50% or more and less than 100% Evaluation B: 25% or more and less than 50% Evaluation C: 10% or more and less than 25% Evaluation D: 0% or more and less than 10%

[0070] [Example 13] A PBAT resin colored sheet F was produced in the same procedure as in Example 12, except that the colored composition F was used instead of the colored composition C. The discoloration rates before and after the decomposition treatment of the PBAT resin colored sheet F were determined.

[0071] [Example 14] A PBAT resin colored sheet G was produced in the same procedure as in Example 12, except that the colored composition G was used instead of the colored composition C. The discoloration rates before and after the decomposition treatment of the PBAT resin colored sheet G were determined.

[0072] [Example 15] A PBSA resin colored sheet C was produced in the same procedure as in Example 12, except that a commercially available PBSA resin pellet (manufactured by Blue Ridge Tunhe Sci. & Tech.) was used instead of the commercially available PBAT resin pellet. The discoloration rates before and after the decomposition treatment of the PBSA resin colored sheet C were determined.

[0073] [Example 16] A PBSA resin colored sheet F was produced in the same procedure as in Example 13, except that a commercially available PBSA resin pellet was used instead of the commercially available PBAT resin pellet. The discoloration rates before and after the decomposition treatment of the PBSA resin colored sheet F were determined.

[0074] [Example 17] A PBSA resin colored sheet G was produced in the same procedure as in Example 14, except that a commercially available PBSA resin pellet was used instead of the commercially available PBAT resin pellet. The discoloration rates before and after the decomposition treatment of the PBSA resin colored sheet G were determined.

[0075] [Comparative Example 1] Except for using coloring composition L instead of coloring composition A, in the same procedure as in Example 1, the decolorization rate of the aqueous solution of colorant L and the decolorization rate before and after the decomposition treatment of PLA dyed fabric L were determined.

[0076] [Comparative Example 2] Except for using coloring composition M instead of coloring composition A, in the same procedure as in Example 1, the decolorization rate of the aqueous solution of colorant M and the decolorization rate before and after the decomposition treatment of PLA dyed fabric M were determined.

[0077] [Comparative Example 3] Except for using coloring composition N instead of coloring composition A, in the same procedure as in Example 1, the decolorization rate of the aqueous solution of colorant N and the decolorization rate before and after the decomposition treatment of PLA dyed fabric N were determined.

[0078] [Comparative Example 4] Except for using coloring composition O instead of coloring composition A, in the same procedure as in Example 1, the decolorization rate of the aqueous solution of colorant O and the decolorization rate before and after the decomposition treatment of PLA dyed fabric O were determined.

[0079] [Comparative Example 5] Except for using coloring composition P instead of coloring composition A, in the same procedure as in Example 1, the decolorization rate of the aqueous solution of colorant P and the decolorization rate before and after the decomposition treatment of PLA dyed fabric P were determined.

[0080] [Comparative Example 6] Except for using coloring composition Q instead of coloring composition A, in the same procedure as in Example 1, the decolorization rate of the aqueous solution of colorant Q and the decolorization rate before and after the decomposition treatment of PLA dyed fabric Q were determined.

[0081] [Comparative Example 7] Except for using coloring composition R instead of coloring composition A, in the same procedure as in Example 1, the decolorization rate of the aqueous solution of colorant R and the decolorization rate before and after the decomposition treatment of PLA dyed fabric R were determined.

[0082] [Comparative Example 8] Except for using coloring composition S instead of coloring composition A, the decolorization rate of the aqueous solution of coloring material S and the decolorization rate of PLA dyed cloth S before and after the decomposition treatment were determined in the same procedure as in Example 1.

[0083] [Comparative Example 9] Except for using Caldry (5 g), a general 100% PET cloth, instead of the polylactic acid cloth made by Unitika, dyeing with polyester resin coloring agent A was carried out in the same manner as in Example 1 to obtain PET dyed cloth A. The decomposition treatment of PET dyed cloth A was carried out under a high temperature and high humidity environment according to the procedure described in Example 1, and the decolorization rate of PET dyed cloth A before and after the decomposition treatment was determined.

[0084] [Comparative Example 10] Except for using coloring composition B instead of coloring composition A, the decolorization rate of PET dyed cloth B before and after the decomposition treatment was determined in the same procedure as in Comparative Example 9.

[0085] [Comparative Example 11] Except for using coloring composition C instead of coloring composition A, the decolorization rate of PET dyed cloth C before and after the decomposition treatment was determined in the same procedure as in Comparative Example 9.

[0086] [Comparative Example 12] Except for using coloring composition D instead of coloring composition A, the decolorization rate of PET dyed cloth D before and after the decomposition treatment was determined in the same procedure as in Comparative Example 9.

[0087] [Comparative Example 13] Except for using coloring composition E instead of polyester resin coloring composition A, the decolorization rate of PET dyed cloth E before and after the decomposition treatment was determined in the same procedure as in Comparative Example 9.

[0088] [Comparative Example 14] Except for using coloring composition I instead of polyester resin coloring composition A, the decolorization rate of PET dyed cloth I before and after the decomposition treatment was determined in the same procedure as in Comparative Example 9.

[0089] [Comparative Example 15] The color fading rate before and after the decomposition treatment of PET dyed cloth K was determined in the same procedure as in Comparative Example 9, except that coloring composition K was used instead of coloring composition A.

[0090] [Comparative Example 16] The color fading rate before and after the decomposition treatment of PET dyed cloth L was determined in the same procedure as in Comparative Example 9, except that coloring composition L was used instead of coloring composition A.

[0091] [Comparative Example 17] The color fading rate before and after the decomposition treatment of PET dyed cloth M was determined in the same procedure as in Comparative Example 9, except that coloring composition M was used instead of coloring composition A.

[0092] [Comparative Example 18] The color fading rate before and after the decomposition treatment of PET dyed cloth O was determined in the same procedure as in Example 9, except that coloring composition O was used instead of coloring composition A.

[0093] [Comparative Example 19] The color fading rate before and after the decomposition treatment of PET dyed cloth P was determined in the same procedure as in Comparative Example 9, except that coloring composition P was used instead of coloring composition A.

[0094] [Comparative Example 20] The color fading rate before and after the decomposition treatment of PET dyed cloth Q was determined in the same procedure as in Comparative Example 9, except that coloring composition Q was used instead of coloring composition A.

[0095] [Comparative Example 21] The color fading rate before and after the decomposition treatment of PET dyed cloth R was determined in the same procedure as in Comparative Example 13, except that coloring composition R was used instead of coloring composition A.

[0096] [Comparative Example 22] The color fading rate before and after the decomposition treatment of PET dyed cloth S was determined in the same procedure as in Comparative Example 13, except that coloring composition S was used instead of coloring composition A.

[0097] [Comparative Example 23] A PBAT resin colored sheet L was obtained in the same procedure as in Example 12, except that a colored resin composition L was used instead of the coloring composition C. Similarly, the color fading rate of the PBAT resin colored sheet L before and after the decomposition treatment was determined.

[0098] [Comparative Example 24] A PBSA resin colored sheet L was obtained in the same procedure as in Example 15, except that a colored resin composition L was used instead of the coloring composition C. Similarly, the color fading rate of the PBSA resin colored sheet L before and after the decomposition treatment was determined.

[0099] [Table 1]

[0100] As is clear from Table 1, it can be seen that the resin colored products obtained in Examples 1 to 17 showed good color fading properties during the decomposition treatment. As the hydrolysis of the polyester resin proceeds under high temperature and high humidity, it is considered that the color fading of the resin colored product progresses by being gradually hydrolyzed from the dye present as a single molecule on the resin surface layer.

[0101] [Table 2]

[0102] On the other hand, as is clear from Table 2, the resin colored products obtained by Comparative Examples 1 to 24 did not show good color fading properties in the decomposition treatment process. Even for an aliphatic polyester resin having a structural unit derived from an aliphatic carboxylic acid having 3 to 6 carbon atoms, a resin composition colored with a colorant having low color fading property in an aqueous solution did not show good color fading property in the decomposition treatment process of the resin colored product. For a resin colored product colored with a colorant having high color fading property in an aqueous solution with respect to an aromatic polyester resin having no structural unit derived from an aliphatic carboxylic acid having 3 to 6 carbon atoms, good color fading property was not shown in the decomposition treatment process. When a polyester resin with low hydrolyzability is colored, it is considered that the color fading of the resin colored product does not progress regardless of the presence or absence of the color fading property of the colorant.

[0103] [Example 18] [Production of PHA resin sheet] (1) Preparation of colorimetric standard 1 g of commercially available PHA resin pellets (BP350-05, manufactured by Bluepha Co., Ltd.) was sandwiched between commercially available cooking sheets, and the resin was preheated and melted using a heat press machine ("AF-65TEN" manufactured by Asahi Fiber Machinery Co., Ltd.) at a set temperature of 200 °C with the pressure set to zero. After that, the resin was rolled under a pressure of 2.4 Mpa and cooled to obtain an uncolored PHA resin sheet.

[0104] (2) Preparation of colored resin sheet 5 g of the aforementioned PHA resin pellets and 10 mg of polyester resin coloring composition B were added to a commercially available plastic bag, and the bag was closed to contain air. The bag was shaken well until the coloring composition B was adsorbed on the surface of the resin pellets. 1 g of the resin pellets was sandwiched between commercially available cooking sheets, and the resin was preheated and melted using a heat press machine at a set temperature of 200 °C with the pressure set to zero. After that, a pressure of 1.6 N / cm 2 was applied to roll the resin, and cooling and rolling were repeated until the coloring became uniform to obtain a PHA resin colored sheet B.

[0105] Except for using the PHA resin colored sheet B instead of the PBAT resin colored sheet C, the decomposition treatment was carried out in a high-temperature and high-humidity environment in the same procedure as in Example 12, and the decolorization rate of the PHA resin colored sheet B was determined using the following formula. X ref : Area value of the spectral density in the visible light region of the uncolored resin sheet before the decomposition treatment Y ref : Area value of the spectral density in the visible light region of the colored resin sheet before the decomposition treatment X: Area value of the spectral density in the visible light region of the uncolored resin sheet after the decomposition treatment Y: Area value of the spectral density in the visible light region of the colored resin sheet after the decomposition treatment Decolorization rate of the colored resin sheet (%) = {1 - (Y - X) / (Y ref - X ref )} × 100 Evaluation A: 65% or more and less than 100% Evaluation B: 45% or more and less than 65% Evaluation C: 25% or more and less than 45% Evaluation D: 0% or more and less than 25%

[0106] [Example 19] A PHA resin colored sheet C was produced in the same procedure as in Example 18, except that coloring composition C was used instead of coloring composition B, and the discoloration rate before and after the decomposition treatment of the PHA resin colored sheet C was determined.

[0107] [Example 20] A PHA resin colored sheet F was produced in the same procedure as in Example 18, except that coloring composition F was used instead of coloring composition B, and the discoloration rate before and after the decomposition treatment of the PHA resin colored sheet F was determined.

[0108] [Example 21] A PHA resin colored sheet J was produced in the same procedure as in Example 18, except that coloring composition J was used instead of coloring composition B, and the discoloration rate before and after the decomposition treatment of the PHA resin colored sheet J was determined.

[0109] [Example 22] The preparation of an aqueous solution of colorant R and the measurement of the discoloration rate were carried out in the same procedure as in Example 1, except that coloring composition R was used instead of coloring composition B, and a PHA resin colored sheet R was produced in the same procedure as in Example 18, and the discoloration rate before and after the decomposition treatment of the PHA resin colored sheet R was determined.

[0110] [Comparative Example 25] A PHA resin colored sheet L was produced in the same procedure as in Example 18, except that coloring composition L was used instead of coloring composition B, and the discoloration rate before and after the decomposition treatment of the PHA resin colored sheet L was determined.

[0111]

Table 3

[0112] As is clear from Table 3, the colored resin materials obtained in Examples 18 to 22 exhibit good decolorization properties during the decomposition treatment. As the hydrolysis of the polyester resin progresses under high temperature and high humidity, it is thought that the decolorization of the colored resin materials progresses as the dye present as a monomolecule on the surface of the resin is gradually hydrolyzed. In contrast, the colored resin material obtained in Comparative Example 25 does not exhibit good decolorization properties in the decomposition treatment process. Similar to the PBAT resin and PBSA resin colored sheets, PHA resin colored sheets colored using colorants with low decolorization properties in aqueous solutions do not exhibit good decolorization properties in the decomposition treatment process of the colored resin material. [Industrial Applicability]

[0113] The coloring composition according to the present invention is useful for coloring aliphatic polyester resins having structural units derived from carboxylic acids having 3 to 6 carbon atoms. The coloring composition can be used to color a variety of resin products, such as fibers and resin molded products. Colored resins are useful in that they allow for easy decolorization of plastic products in recycling processes and that the coloring material is easily degradable along with the resin in composting processes for resin products.

Claims

1. A method for producing a colored aliphatic polyester resin, comprising a step of coloring an aliphatic polyester resin (a) having a structural unit derived from an aliphatic carboxylic acid having 3 to 6 carbon atoms with a coloring composition for an aliphatic polyester resin, wherein the coloring composition for an aliphatic polyester resin contains a colorant (b), and the colorant (b) is such that the reduction rate of the integrated absorbance value in the visible light region before and after leaving an aqueous solution of the colorant obtained by dissolving the colorant (b) in water and an organic solvent at 70 °C for 350 hours is 50% or more.

2. The production method according to Claim 1, wherein the aliphatic polyester resin (a) has biodegradability in a high-temperature and high-humidity environment.

3. The production method according to Claim 1 or 2, wherein the colorant (b) has a structure represented by the following formula (I) or formula (II). 【Chemical 1】 (wherein R １ represents a substituent selected from a substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group, R ２ , R ３ and R ４ represent a hydrogen atom or a substituent, X １ represents a substituted or unsubstituted hydroxy group, amino group, or thiol group, X ２ is NR １０ , NH, an oxygen atom, or a sulfur atom, and R １０ represents a substituent.) 【Chemical formula 2】 (wherein, R ５ and R ７ each represents an unsubstituted, hydrogen atom, or a substituent, R ６ represents a hydrogen atom or a substituent, R ８ represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, X ３ and X ４ each independently represents a carbon atom or a nitrogen atom.)

4. A coloring composition for an aliphatic polyester resin for coloring an aliphatic polyester resin (a) having a structural unit derived from an aliphatic carboxylic acid having 3 to 6 carbon atoms, containing a colorant (b), and the colorant (b) is such that the reduction rate of the integrated absorbance value in the visible light region before and after 350 hours at 70 °C of an aqueous solution of the colorant obtained by dissolving the colorant (b) in water and an organic solvent is 50% or more.

5. The coloring composition for an aliphatic polyester resin according to Claim 4, wherein the aliphatic polyester resin (a) has biodegradability in a high-temperature and high-humidity environment.

6. The coloring composition for an aliphatic polyester resin according to Claim 4 or 5, wherein the colorant (b) has a structure represented by the following formula (I) or formula (II). 【Chemical 3】 (wherein R １ represents a substituent selected from an optionally substituted or unsubstituted aryl group and an optionally substituted or unsubstituted heterocyclic group, and R ２ , R ３ and R ４ represent a hydrogen atom or a substituent, X １ represents a substituted or unsubstituted hydroxy group, amino group, or thiol group, X ２ represents NR １０ , NH, an oxygen atom, or a sulfur atom, and R １０ represents a substituent.) 【Chemical Formula 4】 (wherein R ５ and R ７ each represents unsubstituted, a hydrogen atom, or a substituent, R ６ represents a hydrogen atom or a substituent, R ８ represents a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, X ３ and X ４ each independently represents a carbon atom or a nitrogen atom.)

7. A colored product of an aliphatic polyester resin (a) having a structural unit derived from an aliphatic carboxylic acid having 3 to 6 carbon atoms, colored with a colorant (b), and the colorant (b) is such that the reduction rate of the integrated absorbance value in the visible light region before and after 350 hours at 70 °C of an aqueous solution of the colorant obtained by dissolving the colorant (b) in water and an organic solvent is 50% or more.

8. The colored product according to Claim 7, wherein the aliphatic polyester resin (a) has biodegradability in a high-temperature and high-humidity environment.

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