Pigment composition, resin composition, and molded article

Abstract

To provide a pigment composition which is used for nylon 6 and nylon 66 resin coloring, hardly generates fading and hue change before and after molding even at high temperature (for example, 260-300°C) in injection molding, and contains chlorinated metal phthalocyanine.SOLUTION: A pigment composition for nylon 6 and / or nylon 6, 6 resin coloring contains a metal phthalocyanine pigment having an average number of chlorine substituents of less than 4. Central metal in the metal phthalocyanine pigment is preferably copper. The resin composition contains a metal phthalocyanine pigment having an average number of chlorine substituents of less than 4, and a nylon 6 and / or nylon 6, 6 resin having an average molecular weight of 10,000 to 25,000.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a pigment composition for coloring nylon 6 and / or nylon 6,6 resin, a resin composition containing the same, and a molded article of the resin composition. [Background technology]

[0002] The market for pigments for coloring plastics (particularly engineering plastics) is in demand for pigments with high heat resistance and high stability. Currently, phthalocyanine pigments, quinacridone pigments, and the like are used as such pigments. Among these, the following Patent Documents 1 to 4 are cited as examples of phthalocyanine pigments for coloring plastics.

[0003] Patent Documents 1 to 4 describe the use of halogenated metal phthalocyanine pigments with a specific range of halogen substituents, such as chlorine. They also describe resins to be colored, such as polyethylenes (e.g., high-density polyethylene (HDPE) and low-density polyethylene (LDPE)), polyolefins (e.g., polypropylene), polyester resins (e.g., polyethylene terephthalate), polyamide resins (e.g., nylon 6 and nylon 66), polystyrene resins, and thermoplastic ionomer resins. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-131612 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-183071 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-023222 [Patent Document 4] Japanese Patent Application Publication No. 2-91159 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0005] As a result of investigations, the present inventors have found that, among the halogenated metal phthalocyanine pigments and colored resins described in Patent Documents 1 to 4, in specific combinations of chlorinated metal phthalocyanine pigments having a certain number of chlorines or more with nylon 6 and nylon 66 resins, fading of the phthalocyanine pigment at high temperatures during injection molding and a significant change in hue before and after molding occur (see Comparative Examples 1 and 2 of the present application).Surprisingly, it was found that this fading and change in hue before and after molding do not occur when the resin is changed to a resin other than nylon 6 and nylon 66 resins (for example, polypropylene) (see Comparative Examples 4 and 5 of the present application).

[0006] Nylon 6 and nylon 66 are important resins in industry, being widely used as engineering plastics in fibers, automobile parts, electrical and electronic devices, various molded products, etc. The present invention provides a pigment composition containing a chlorinated metal phthalocyanine for coloring nylon 6 and nylon 66 resins, which is resistant to fading and hue change before and after molding even at high temperatures (e.g., 260-300°C) during injection molding. [Means for solving the problem]

[0007] The inventors of the present invention predicted that the main cause of discoloration and hue change during molding was a change in pigment structure due to a chemical reaction between the nylon resin and the chlorinated metal phthalocyanine pigment, and further investigated the number of chlorine substituents that are thought to contribute to the reaction. As a result, they found that with specific combinations of chlorinated metal phthalocyanine pigments with a chlorine number of less than four and nylon 6 and nylon 66 resins, there was almost no discoloration at high temperatures during injection molding, and almost no change in hue before and after molding.

[0008] The mechanism assumed in the present invention is as follows. Typically, phthalocyanine pigments have a planar structure with π-electron conjugation extending throughout the molecule, providing heat resistance. Furthermore, when the coloring resin is nylon resin, the interaction between the amide bonds in the nylon resin and the phthalocyanine pigment is thought to stabilize the structure. Therefore, the phthalocyanine pigment is less likely to fade or change in hue before and after molding, as described above. However, in the case of chlorinated metal phthalocyanine pigments, the presence of chlorine atoms, an electron-withdrawing group, weakens the π-electron conjugation throughout the molecule because electrons are attracted to the chlorine atoms at the ends of the structure. As a result, the interaction between the amide bonds in the phthalocyanine pigment and the nylon resin also weakens, leaving the chlorinated metal phthalocyanine pigment in an unstable, free state, which tends to reduce its heat resistance. Furthermore, chemical reactions between the chlorine atoms in the chlorinated metal phthalocyanine pigment and the amide groups in the nylon resin can cause fading and hue changes. In this mechanism, if the number of substituted chlorine atoms in a chlorinated metal phthalocyanine pigment exceeds four, significant deterioration in heat resistance, such as fading and hue changes, is thought to result. Furthermore, among commonly used nylon resins, nylon 6 and nylon 6,6 have a relatively high proportion of amide bonds in the polymer structure, and it is believed that the interaction between the amide bonds and the phthalocyanine pigment in the above-mentioned mechanism has a large effect. Note that it is believed that resins other than nylon (e.g., polypropylene) do not suffer from the deterioration in heat resistance, such as fading and hue change, due to the above-mentioned mechanism.

[0009] That is, the present invention is Item 1. A pigment composition for coloring nylon 6 and / or nylon 6,6 resin, containing a metal phthalocyanine pigment having an average number of chlorine substituents of less than 4. Item 2. The pigment composition according to Item 1, wherein the central metal in the metal phthalocyanine pigment is copper. Item 3. A resin composition comprising a metal phthalocyanine pigment having an average number of chlorine substituents of less than 4 and a nylon 6 and / or nylon 6,6 resin having an average molecular weight of 10,000 to 25,000. Item 4. A molded article molded using the resin composition described in Item 3. Regarding. [Effects of the Invention]

[0010] The pigment composition of the present invention, when used to color nylon 6 and / or nylon 6,6 resin, exhibits excellent heat resistance, with little fading or change in hue at high temperatures (e.g., 260 to 300°C) during injection molding. Similarly, the resin composition of the present invention also exhibits excellent heat resistance. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in detail below.

[0012] <Pigment composition> The pigment composition of the present invention is for coloring nylon 6 and / or nylon 6,6 resin, and contains a metal phthalocyanine pigment having an average number of chlorine substituents of less than 4. The average number of chlorine substituents in the metal phthalocyanine pigment is preferably 0 to 3, more preferably 0 to 2, and even more preferably 0 to 1. When the average number of chlorine substituents is within the above range, fading and hue change at high temperatures during injection molding are small, and the heat resistance is excellent. The metal phthalocyanine pigment may have substituents other than chlorine (for example, fluorine and bromine).

[0013] Examples of the central metal in the metal phthalocyanine pigment include copper (Cu), zinc (Zn), nickel (Ni), cobalt (Co), iron (Fe), aluminum (Al), chromium (Cr), and manganese (Mn), with copper being preferred. Copper phthalocyanine pigments with copper as the central metal are widely used in the field of plastic coloring and have been found to exhibit excellent heat resistance in the present invention. Copper phthalocyanine can take various crystal forms, such as α-, β-, and ε-type, but from the viewpoint of heat resistance, α- or β-type is preferred, and β-type is more preferred.

[0014] Examples of the metal phthalocyanine pigment include blue pigments such as CI Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, and 15:6. Among these, copper phthalocyanine pigments such as CI Pigment Blue 15:1, 15:3, and 15:4 are preferred in the present invention. In the present invention, one type of the metal phthalocyanine pigment may be used alone, or two or more types may be used in combination.

[0015] Copper phthalocyanine pigments can be synthesized by the urea method using phthalic anhydride, urea, and a copper compound as starting materials, or the phthalodinitrile method using phthalodinitrile and a copper compound, and synthesized copper phthalocyanine pigments may be used in the present invention. Commercially available copper phthalocyanine pigments may also be used, such as the FASTOGEN® BLUE series (manufactured by DIC Corporation) and the SUNFAST® BLUE series (manufactured by Sun Chemical Co., Ltd.).

[0016] The pigment composition of the present invention may contain metal phthalocyanine pigments other than the above-mentioned metal phthalocyanine pigments (CI Pigment Green 7, CI Pigment Green 36, etc.) or other pigments (organic pigments such as threne-based pigments, indigo-based pigments, perinone-based pigments, perylene-based pigments, phthalone-based pigments, dioxazine-based pigments, quinacridone-based pigments, isoindolinone-based pigments, metal complex-based pigments, diketopyrrolopyrrole-based pigments, and azo pigments, and inorganic pigments such as titanium oxide and carbon black), within the scope that does not impair the effects of the present invention.

[0017] The pigment composition of the present invention is used for coloring nylon 6 and / or nylon 6,6 resin, and the average molecular weight of these nylons is preferably 10,000 to 25,000, more preferably 12,000 to 18,000. If the average molecular weight is less than 10,000, the compatibility between the pigment and the resin is high, making it difficult to ensure high heat resistance, while if the average molecular weight exceeds 25,000, the compatibility between the pigment and the resin is low, which can cause color unevenness, etc. The average molecular weight is the number average molecular weight and can be measured by GPC analysis using polystyrene as a standard substance.

[0018] Nylon 6 (PA6) may be synthesized by ring-opening polymerization of caprolactam (carbon number 6), but commercially available products that can be used include, for example, UBE Nylon (manufactured by Ube Industries, Ltd.), Tanajin (registered trademark) TN200, TN500, etc. (manufactured by Takayasu Corporation), Glamid (registered trademark) T-802, etc. (manufactured by Toyobo Co., Ltd.), Amilan (registered trademark) CM1017, CM1007, CM1026, etc. (manufactured by Toray Industries, Inc.), and Unitika Nylon 6 (manufactured by Unitika Ltd.). Nylon 66 (PA66) may be synthesized by condensation polymerization of hexamethylenediamine (carbon number: 6) and adipic acid (carbon number: 6). Commercially available products that can be used include Leona (registered trademark) 1300S (manufactured by Asahi Kasei Corporation), Tanajin (registered trademark) TN720, TN710, etc. (manufactured by Takayasu Co., Ltd.), Glamid (registered trademark) T-662, etc. (manufactured by Toyobo Co., Ltd.), and Amilan (registered trademark) CM3007, CM3001-N, etc. (manufactured by Toray Industries, Inc.).

[0019] The reasons why nylon 6 and nylon 6,6 are focused on as nylon (polyamide resin) in the present invention will be described in detail below. Generally, there are the following types of nylon (indicating the monomers and the number of carbon atoms that make up each). Nylon 6: ε-caprolactam (carbon number 6) Nylon 11: Undecane lactam (carbon number 11) Nylon 12: Lauryl lactam (carbon number 12) Nylon 6,6: hexamethylenediamine (carbon number 6) + adipic acid (carbon number 6) Nylon 6,10: hexamethylenediamine (carbon number 6) + sebacic acid (carbon number 10) Nylon 6T: Hexamethylenediamine (carbon number 6) + terephthalic acid Nylon 6I: Hexamethylenediamine (carbon number 6) + Isophthalic acid Nylon 9T: Nonanediamine (carbon number 9) + terephthalic acid Nylon M5T: Methylpentadiamine (methyl group + carbon number 5) + terephthalic acid In the present invention, as explained by the above-mentioned mechanism, a relatively high proportion of amide bonds in the polymer structure is preferable, and therefore, it is preferable that the number of constituent carbon atoms is small and that aromatic structures other than amide bonds, such as phthalic acid, are not contained. Therefore, in the present invention, aliphatic polyamides, particularly nylons having 5 or 6 constituent carbon atoms, are preferred. For these reasons, the pigment composition of the present invention is intended for coloring nylon 6 and / or nylon 6,6 resins.

[0020] The pigment composition of the present invention preferably contains a pigment dispersant in addition to the pigment. Examples of such pigment dispersants include metal soaps such as calcium stearate, zinc stearate, magnesium stearate, and lithium stearate, fatty acid amides such as stearamide and ethylene bisamide, ester waxes, polyethylene waxes, and silane coupling agents. Among these, magnesium stearate is preferred. The amount of pigment dispersant per 100 parts by mass of the pigment is, for example, 50 to 500 parts by mass, and preferably 100 to 400 parts by mass.

[0021] The method for coloring the resin in the pigment composition of the present invention may be any of methods such as masterbatch, dry color, paste color (liquid masterbatch), and the like.

[0022] <Resin composition> The resin composition of the present invention contains a metal phthalocyanine pigment having an average number of chlorine substituents of less than four, and a nylon 6 and / or nylon 6,6 resin having an average molecular weight of 10,000 to 25,000. The metal phthalocyanine pigment is as described above for the pigment composition of the present invention, and the nylon 6 and / or nylon 6,6 resin is as described above for the pigment composition of the present invention. The resin composition of the present invention may also contain the pigment dispersant described above for the pigment composition of the present invention.

[0023] The ratio of the pigment containing the metal phthalocyanine pigment to 100 parts by mass of nylon 6 and / or nylon 6,6 resin is, for example, 0.001 to 1 part by mass, preferably 0.01 to 0.5 parts by mass. The ratio of the pigment composition of the present invention, in which a pigment dispersant is added to the pigment, to 100 parts by mass of nylon 6 and / or nylon 6,6 resin is, for example, 0.002 to 1 part by mass, preferably 0.01 to 0.5 parts by mass.

[0024] The resin composition of the present invention may contain a resin other than the nylon 6 and / or nylon 6,6 resin as long as the effects of the present invention are not impaired. Examples of such resins include polyamide resins other than nylon 6 and nylon 6,6, homopolymers and copolymers using ethylene, propylene, butylene, styrene, or the like as monomer components, polyethylenes such as high-density polyethylene (HDPE), linear low-density polyethylene (L-LDPE), and low-density polyethylene (LDPE), polyolefin resins such as polypropylene and polybutylene, polyester resins such as polyethylene terephthalate, polystyrene resins, and thermoplastic ionomer resins.

[0025] The resin composition of the present invention may contain, in addition to the above-mentioned metal phthalocyanine pigment, other pigments and pigment dispersants, nylon 6 and / or nylon 6,6, and other resins, lubricants, plasticizers, fillers, weather stabilizers, various additives, and the like.

[0026] The lubricant may be either an internal lubricant or an external lubricant, and examples thereof include hydrocarbon compounds such as paraffin wax, synthetic polyethylene, and liquid paraffin; fatty acid / higher alcohol compounds such as stearic acid, behenic acid, 12-hydroxystearic acid, and stearyl alcohol; fatty acid amide compounds such as stearic acid amide, oleic acid amide, erucic acid amide, methylene bisstearic acid amide, and ethylene bisstearic acid amide; and ester compounds such as glycerin monostearate, glycerin monooleate, and butyl stearate.

[0027] Examples of the plasticizer include epoxidized vegetable oils such as epoxidized soybean oil (ESBO) and epoxidized linseed oil (ELSO), phthalate esters such as dioctyl phthalate (DOP) and dibutyl phthalate (DBP), and polyester compounds such as polyesters of dibasic acids (adipic acid, sebacic acid, phthalic acid, etc.) and glycols (1,2-propanediol, butanediol, etc.).

[0028] The filler may be appropriately selected depending on the desired physical properties, and examples of the filler include wollastonite, potassium titanate, xonotlite, gypsum fiber, aluminum borate, MOS, aramid fiber, various fibers, carbon fiber, glass fiber, talc, mica, glass flakes, polyoxybenzoyl whisker, calcium carbonate, talc, silica, and clay.

[0029] Examples of the weather resistance stabilizer include ultraviolet absorbers such as triazine-based, benzotriazole-based, benzophenone-based, salicylate-based, and cyanoacrylate-based compounds; light stabilizers such as hindered amine light stabilizers (HALS); antioxidants such as phenol-based (hindered phenol-based, etc.), phosphorus-based (phosphite-based, etc.), and sulfur-based (thioether-based, etc.) antioxidants; heavy metal inactivators; and chelating agents.

[0030] Examples of the various additives include intumescent, phosphate, halogen, and inorganic flame retardants, nucleating agents such as metal phosphate salts and sorbitol, fillers such as talc and calcium carbonate, compatibilizers (reactive and non-reactive), clarifying agents such as metal phosphate salts and sorbitol, and nonionic, anionic, and cationic antistatic agents.

[0031] The resin composition of the present invention contains a metal phthalocyanine pigment having an average number of chlorine substituents of less than four and nylon 6 and / or nylon 6,6 resin, and therefore exhibits excellent heat resistance and little fading or hue change at high temperatures during injection molding, similar to the pigment composition of the present invention. The resin coloring method for the resin composition of the present invention may be any method, such as masterbatch, dry color, or paste color (liquid masterbatch).

[0032] <Molded products> The molded article of the present invention is a colored nylon 6 or nylon 6,6 article molded using the resin composition of the present invention. The molding method may be any of injection molding, blow molding, inflation molding, extrusion molding, Engel molding, vacuum molding, etc., but injection molding is preferred. Injection molding can be performed under typical conditions for molding nylon 6 and nylon 6,6, with the resin temperature (cylinder temperature) being, for example, 260 to 300°C.

[0033] The molded articles of the present invention can be used for a variety of purposes, including automobile and vehicle parts (engine room parts, intake system parts, fuel system parts, etc.), electrical and electronic equipment (industrial equipment connectors, switches, housings, etc.), injection and extrusion molded articles for processing such as films, sheets, pipes, plates, round bars, and tubes, daily necessities, containers, toys, building materials, and sporting goods. [Example]

[0034] The present invention will be described in more detail below using examples and comparative examples.

[0035] [Example 1] First, 1 g of DIC's FASTOGEN BLUE 5050GE (CI Pigment Blue 15:1) and 1 g of Sakai Chemical Industry's magnesium stearate were thoroughly mixed to prepare 2 g of dry color. Next, the prepared dry color was added to 1,000 g of nylon resin (nylon 6, product name: UBE NYLON 1013NW8, manufacturer: Ube Industries, Ltd.) and thoroughly mixed to obtain colored pellets. These colored pellets were then placed in an injection molding machine (Nissei Plastic Industrial Co., Ltd.; model number: PNX60III-5A) and molded at 280 °C with residence times of 0 and 10 minutes.

[0036] [Example 2] Molding was carried out in the same manner as in Example 1, except that the pigment was changed to FASTOGEN BLUE GR-6LK (CI Pigment Blue 15:3) manufactured by DIC Corporation.

[0037] [Example 3] Molding was carried out in the same manner as in Example 1, except that the pigment was changed to SUNFAST BLUE 15:4 249-3450 (CI Pigment Blue 15:4) manufactured by SUN.

[0038] [Example 4] Molding was carried out in the same manner as in Example 1, except that the pigment was changed to SUNFAST BLUE 15:1 248-4816 (CI Pigment Blue 15:1) manufactured by SUN.

[0039] [Comparative Example 1] Molding was carried out in the same manner as in Example 1, except that the pigment was changed to SUNFAST GREEN 36 264-7036 (CI Pigment Green 36) manufactured by SUN.

[0040] Comparative Example 2 Molding was carried out in the same manner as in Example 1, except that the pigment was changed to SUNFAST GREEN 7 264-7405 (CI Pigment Green 7) manufactured by SUN.

[0041] Comparative Example 3 2g of dry color, a mixture of 1g of DIC's FASTOGEN BLUE 5050GE (CI Pigment Blue 15:1) and 1g of Sakai Chemical Industry's magnesium stearate, was added to 1000g of polypropylene resin (product name: Novatec PP MA3, manufacturer: Japan Polypropylene Corporation) and mixed thoroughly. This mixture was then placed in an injection molding machine (Nissei Plastic Industrial Co., Ltd.) and molded at 280°C with residence times of 0 and 10 minutes.

[0042] Comparative Example 4 Molding was carried out in the same manner as in Comparative Example 3, except that the pigment was changed to SUNFAST GREEN 36 264-7036 (CI Pigment Green 36) manufactured by SUN.

[0043] Comparative Example 5 Molding was carried out in the same manner as in Comparative Example 3, except that the pigment was changed to SUNFAST GREEN 7 264-7405 (CI Pigment Green 7) manufactured by SUN Corporation.

[0044] [Heat resistance evaluation] Two molded plates molded at 280°C with a residence time of 0 minutes and 10 minutes were measured for color. The color measurement value of the molded plate with a residence time of 0 minutes was used as the standard, and the dE* value of the molded plate with a residence time of 10 minutes was calculated. Note that the smaller the dE* value, the higher the heat resistance and stability of the pigment.

[0045] [Table 1]

[0046] As shown in Table 1 above, when the metal phthalocyanine pigments of Examples 1-4, each having less than 4 chlorine atoms, were used in nylon 6, the dE / nylon value was smaller than that of Comparative Examples 1-2, each having 4 or more chlorine atoms, resulting in higher heat resistance and stability. On the other hand, when the metal phthalocyanine pigment of Comparative Example 3, each having less than 4 chlorine atoms, was used in polypropylene resin (PP), the dE / PP value was larger than that of Comparative Example 4, each having 4 chlorine atoms, resulting in lower heat resistance and stability. In other words, it was found that the pigment composition of the present invention is useful for coloring nylon 6 and / or nylon 6,6 resin.

Claims

1. a pigment composition; A resin composition containing nylon 6 and / or nylon 6,6 resin, the pigment composition contains only a copper phthalocyanine pigment having an average number of chlorine substituents of 0 to 2 as a pigment, the ratio of the pigment to 100 parts by mass of the nylon 6 and / or nylon 6,6 resin is 0.001 to 0.5 parts by mass, The resin composition, wherein the copper phthalocyanine pigment having an average number of chlorine substituents of 0 to 2 is selected from the group consisting of C.I. Pigment Blue 15:1 and C.I. Pigment Blue 15:

4.

2. The resin composition according to claim 1 , wherein the pigment composition further comprises a pigment dispersant.

3. A resin composition as described in claim 2, wherein the pigment dispersant is magnesium stearate.

4. 4. The resin composition according to claim 2, wherein the amount of the pigment dispersant is 50 to 500 parts by mass relative to 100 parts by mass of the pigment.

5. The resin composition according to any one of claims 1 to 4, wherein the nylon 6 and / or nylon 6,6 resin has a number average molecular weight of 10,000 to 25,000.

6. A molded article molded using the resin composition according to any one of claims 1 to 5.

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