JP2022092732A - Colored resin composition and molded body - Google Patents

Abstract

To provide a colored resin composition excellent in bleeding performance and mutual adhesion without impairing the hue of an organic pigment when a polyolefin resin is colored with an organic pigment and to provide a molded body obtained by forming the same which can suppress warpage and shrinkage.SOLUTION: There is provided a colored resin composition which comprises a polyolefin resin (A), an organic pigment (B) and a compatibilizer (C), wherein the compatibilizer (C) contains a polyolefin elastomer, ΔMDS represented by the following expression (1) satisfies 0.35% or less and ΔTDS represented by the following expression (2) satisfies 0.35% or less: Expression (1) ΔMDS=|X1-X0|, Expression (2) ΔTDS=|Y1-Y0|.SELECTED DRAWING: None

Description

The present invention relates to a colored resin composition and a molded product formed from the colored resin composition.

Since plastic is easy to mold, it is used in a wide range of fields such as electrical and electronic equipment parts, automobile parts, medical parts, food containers, etc., and the plastic molded body is actively colored to enhance its decorativeness. ing. In particular, in the field of beverage caps and containers, multicoloring is progressing for product differentiation, and molded bodies with various colors and designs are distributed in the market.

Among these, in the field of beverage caps and containers, polyolefin resins are often used because they have high resistance to the contents and are easy to mold. However, when the polyolefin resin is colored with a pigment, the pigment becomes the starting point of crystallization of the resin, and the crystallization of the resin may proceed along the crystal direction of the pigment (hereinafter, may be referred to as a nucleation effect). At this time, since crystals different from the crystal structure of the original resin are formed, dimensional problems such as warpage and shrinkage occur in the resin molded body. Such warpage and shrinkage of the molded product are likely to occur when an organic pigment is used as the colorant.

As a method of suppressing warpage and shrinkage of the polyolefin resin due to the organic pigment, a method of surface-treating the pigment and adding a derivative (Patent Documents 1 and 2) and a method of changing the composition of the polyolefin resin (Patent Document 3) are known. ing. However, these methods adversely affect the hue, bleeding property, surface peeling property, and mutual adhesion between resins of the pigment. Further, there is a problem that it can be used only for a polyolefin resin having a limited composition.

Further, a method of suppressing warpage and shrinkage by adding a crystal nucleating agent to a polyolefin resin is known (Patent Document 4). With this method, it is possible to suppress warpage and shrinkage when the polyolefin resin is colored with an organic pigment, but in recent years, the market has demanded more strictly control of dimensional changes due to coloring. Therefore, it has not been possible to achieve dimensional stability with such high accuracy.

Japanese Unexamined Patent Publication No. 4-226542 Japanese Unexamined Patent Publication No. 2001-89612 Japanese Patent No. 9-246718 Japanese Unexamined Patent Publication No. 2006-225576

INDUSTRIAL APPLICABILITY The present invention comprises a colored resin composition having excellent bleeding property, surface peeling property, and mutual adhesion without impairing the hue of the organic pigment when the polyolefin resin is colored with an organic pigment, and a warp formed by the composition. And, an object of the present invention is to provide a molded product in which shrinkage is suppressed.

The present inventor has completed the present invention as a result of diligent studies to solve the above problems. That is, the colored resin composition of the present invention is a colored resin composition containing a polyolefin resin (A), an organic pigment (B), and a compatibilizer (C).
The compatibilizer (C) contains a polyolefin elastomer and contains
The present invention relates to a colored resin composition characterized in that ΔMDS represented by the following formula (1) is 0.35% or less and ΔTDS represented by the following formula (2) is 0.35% or less.

Equation (1) ΔMDS = | X1-X0 |
Equation (2) ΔTDS = | Y1-Y0 |

(Note that X1 and Y1 are each in the same direction as the injection direction one day after molding of a molded product having a length of 150 mm, a width of 120 mm and a thickness of 2 mm, which is molded from a colored resin composition by an injection molding machine. The shrinkage rate in the MD direction) and the shrinkage rate in the direction perpendicular to the injection direction (TD).
X0 and Y0 are the same directions (MD direction) as the injection direction one day after molding of a molded product having a length of 150 mm, a width of 120 mm and a thickness of 2 mm, which is molded from the polyolefin resin (A) by an injection molding machine, respectively. ), And the shrinkage rate in the direction perpendicular to the injection direction (TD). )

INDUSTRIAL APPLICABILITY According to the present invention, when a polyolefin resin is colored with an organic pigment, a colored resin composition having excellent bleeding property, surface peeling property, and mutual adhesion without impairing the hue of the organic pigment, and a warp formed by the composition. And it becomes possible to provide a molded product capable of suppressing shrinkage.

Hereinafter, embodiments of the present invention will be described in detail, but the following description is an example (representative example) of embodiments of the present invention, and the present invention is not limited to these contents as long as the gist thereof is not exceeded.
In addition, the numerical range specified by using "-" in the present specification shall include the numerical values before and after "-" as the range of the lower limit value and the upper limit value.
Unless otherwise noted, the various components appearing in the present specification may be used independently or in combination of two or more.
C.I. I. Means the color index.

<< Colored resin composition >>
The colored resin composition of the present invention is used to form a molded product obtained by coloring the polyolefin resin (A) with an organic pigment. The colored resin composition contains a polyolefin resin (A), an organic pigment (B), and a compatibilizer (C), and the compatibilizer (C) contains a polyolefin elastomer.
Further, the ΔMDS represented by the following formula (1) is 0.35% or less, and the ΔTDS represented by the following formula (2) is 0.35% or less.

Equation (1) ΔMDS = | X1-X0 |
Equation (2) ΔTDS = | Y1-Y0 |

X1 is a shrinkage rate of a molded product having a length of 150 mm, a width of 120 mm, and a thickness of 2 mm, which is obtained by molding a colored resin composition by an injection molding machine, in the same direction (MD direction) as the injection direction one day after molding. Y1 is the shrinkage rate in the direction perpendicular to the injection direction (TD).

X0 is a shrinkage of a molded product having a length of 150 mm, a width of 120 mm, and a thickness of 2 mm, which is obtained by molding a polyolefin resin (A) by an injection molding machine, in the same direction (MD direction) as the injection direction one day after molding. It is a rate, and Y0 is a shrinkage rate in the direction perpendicular to the injection direction (TD).

When the polyolefin resin (A) is a mixture, X0 and Y0 can be obtained by using a molded body containing only the polyolefin resin (A) having the largest resin ratio contained in the polyolefin resin (A). When the ratio of the plurality of resins contained is the same, the formed body using the polyolefin resin (A) having the smallest shrinkage rate is used as a reference.

When ΔMDS and ΔTDS are 0.35% or less, it can be said that the molded product maintains dimensional stability with high accuracy in which the change in dimensions due to coloring with an organic pigment is controlled.
ΔMDS is more preferably 0.3% or less, further preferably 0.2% or less, and more preferably closer to 0%. Further, the ΔTDS is more preferably 0.3% or less, preferably 0.2% or less, and more preferably closer to 0%.
Within this range, it can be said that the molded product has a shrinkage difference controlled at the same level as the molded product made of uncolored resin.

The colored resin composition is obtained by kneading the organic pigment (B) and the compatibilizer (C) at a temperature at which the polyolefin resin (A) melts. As a method for producing the colored resin composition, for example, a polyolefin resin (A), an organic pigment (B), a compatibilizer (C), and various additives as necessary are added, and a kneader, a roll mill, or a super mixer is used. , High-speed mixer, ball mill, sand mill, attritor, batch kneader such as Banbury mixer, single-screw extruder, twin-screw extruder, rotor-type twin-screw kneader, etc. It can be a body-shaped, granular or bead-shaped resin composition. Since the kneading force is strong and the subsequent molding process is easy, it is preferable to make pellets by a single-screw extruder or a twin-screw extruder.

The colored resin composition may be obtained by blending a required amount of an organic pigment (B) and a compatibilizer (C) with a polyolefin resin (A) and using it as it is for molding, or once containing the organic pigment (B) at a high concentration. You may prepare a masterbatch to be used, dilute it with a diluting resin, and use it for molding.

<Polyolefin resin (A)>
The polyolefin resin (A) in the present invention is a polymer of an olefin monomer such as ethylene, propylene, and butylene, and may be a block or a random copolymer having a melting point in the range of 40 to 200 ° C., a bipolymer, or a bipolymer. It may be a terpolymer or the like. Specific examples include polymers of α-olefins such as linear low density polyethylene resin (LLDPE), low density polyethylene resin (LDPE), high density polyethylene resin (HDPE), and polypropylene resin (PP). Be done.
The polyolefin resin (A) is preferably HDPE or PP having high crystallinity because the effects of the present invention can be easily obtained.
The melting point in the present specification is a value measured using a differential scanning calorimeter "DSC6200" (manufactured by Seiko Instruments, Inc.) under the conditions of a temperature range of 40 to 200 ° C. and a heating rate of 10 ° C./min.

Once a masterbatch is used, the MFR (melt flow rate, also referred to as melt viscosity) of the polyolefin resin (A) is preferably 5 to 100 g / 10 minutes, more preferably 10 to 60 g / 10 minutes. If the MFR of the polyolefin resin (A) is 5 g / 10 minutes or more, the masterbatch is sufficiently distributed when the masterbatch is added to the diluted resin, and the molded product has an appearance defect such as color unevenness. It can be more suppressed. On the other hand, if the MFR is 100 g / 10 minutes or less, it is possible to prevent the melt viscosity of the entire system from decreasing during molding and affecting the moldability. The polyolefin resin (A) and the diluted resin used in the masterbatch are preferably the same type of polyolefin resin. For example, when the polyolefin resin (A) which is a diluted resin is HDPE, it is preferable that the polyolefin resin (A) in the masterbatch is also HDPE.

In the colored resin composition, when the polyolefin resin (A) is a high-density polyethylene resin (HDPE) or a polypropylene resin (PP), the MFR of the polyolefin resin (A) is preferably 5 g / 10 minutes or less, and 0.1 to 0.1 to 5 g / 10 minutes is more preferable. When the MFR of the polyolefin resin (A) is 0.1 g / 10 minutes or more, the processability of the colored resin composition becomes better, and when it is 5 g / 10 minutes or less, the strength of the molded product becomes higher. It will be good.
The MFR in the present invention is a value measured according to JIS (Japanese Industrial Standards) K-7210.

Specific examples of the polyolefin resin (A) include Novatec LL UJ580 (LLDPE, MFR: 20 g / 10 minutes, manufactured by Nippon Polyethylene), Suntech LD M2270 (LDPE, MFR: 7 g / 10 minutes, manufactured by Asahi Kasei Co., Ltd.), Suntech HD. J240 (HDPE, MFR: 5g / 10 minutes, manufactured by Asahi Kasei Co., Ltd.), Suntech HD J300 (HDPE, MFR: 42g / 10 minutes), Prime Polypro J229E (PP, MFR: 50g / 10 minutes, manufactured by Prime Polymer Co., Ltd.), etc. Can be mentioned.

The content of the polyolefin resin (A) in 100% by mass of the resin composition is preferably 60% by mass or more and 100% by mass or less, and more preferably 90% by mass or more. When the blending amount of the polyolefin resin (A) is 60% by mass or more, it is easy to sufficiently maintain the strength of the molded product.

<Organic pigment (B)>
The organic pigment (B) in the present invention is not particularly limited as long as it is a pigment made of an organic substance.
Examples thereof include azo pigments, quinacridone pigments, perylene pigments, isoindolinone pigments, diketopyrrolopyrrole pigments, and phthalocyanine pigments. Among them, azo pigments, quinacridone pigments, perylene pigments, isoindolinone pigments, and diketopyrrolopyrrole pigments have high compatibility with the compatibilizer (C) and are preferable in terms of shrinkage. More preferably, a diketopyrrolopyrrole pigment having good dispersibility as a pigment is preferable in that it has an excellent hue.

Specific examples of the azo pigment include C.I. I. Pigment Yellow 93, 95, 150, 151, 168, 169, 180, 181 and C.I. I. Pigment Red 144, 208, 214,
Specific examples of the quinacridone pigment include C.I. I. Pigment Red 122, 207, C.I. I. Pigment Vio Red 19,
Specific examples of the perylene pigment include C.I. I. Pigment Red 149, 178,
Specific examples of the isoindolinone pigment include C.I. I. Pigment Yellow 109, 110, 139, C.I. I. Pigment Orange 61,
Specific examples of the diketopyrrolopyrrolopyrrole pigment include C.I. I. Pigment Red 254, 264, C.I. I. Pigment Orange 71
And so on.

Specific examples of Pigment Yellow 93 are Chromophthal Yellow 3GNP (manufactured by BASF), Specific examples of Pigment Yellow 95 are Chromophthal Yellow GRP (manufactured by BASF), and specific examples of Pigment Yellow 150 are Binamon Yellow 115002 (manufactured by BASF). A specific example of PV First Yellow H4G (manufactured by Clariant) is PV First Yellow H4G (manufactured by Clariant), a specific example of Pigment Yellow 168 is Lionol Yellow K5G (manufactured by Toyo Color Co., Ltd.), and a specific example of Pigment Yellow 169 is Specific examples of Lionol Yellow K2R (manufactured by Toyo Color) and Pigment Yellow 180 are PV Fast Yellow HG (manufactured by Clariant), and specific examples of Pigment Yellow 181 are PV Fast Yellow H3R (manufactured by Clariant) and Pigment Red 144. Specific example of is Chromophthalred BRN (manufactured by BASF), specific example of Pigment Red 208 is Graftor Red HF2B (manufactured by BASF), and specific example of Pigment Red 214 is Chromophthalred BN (manufactured by BASF). , Specific examples of Pigment Red 122 are Fastgen Super Magenda RE03 (manufactured by DIC), Binamon Red 312201 (manufactured by Hoiba), Specific examples of Pigment Red 207 are Fastgen Super Scarlet GK (manufactured by DIC), Pigment. A specific example of Bio Red 19 is Chrome Phtal Red 2020 (manufactured by BASF), a specific example of Pigment Red 149 is Paliogen Red K3580 (manufactured by BASF), and a specific example of Pigment Red 178 is Paliogen Red K3911HD (BASF). Specific examples of Pigment Red 254 are Chromophtal Red 2028 (manufactured by BASF), Specific examples of Pigment Red 264 are Irgazine DPP Rubin TR (manufactured by BASF), and specific examples of Pigment Orange 71 are Chromophtal DPP. Examples include Orange TRP (manufactured by BASF).

The organic pigment (B) preferably has a structure having a polar functional group. This is because having a polar functional group has high compatibility with the compatibilizer (C).
Specific examples of the pigment having a polar functional group include C.I. I. Pigment Yellow 93, 95, 110, 150, 151, C.I. I. Pigment Red 122, 149, 207, 254, C.I. I. Pigment Violet 19 and the like.

The content of the organic pigment (B) is preferably 0.01% by mass or more, more preferably 0.1% by mass or more and 1% by mass or less, and 0.3% by mass or more in 100% by mass of the colored resin composition. Less than 0.8% by mass is more preferable.
When the content of the organic pigment (B) is in the above range, it becomes easy to achieve both the dispersibility of the organic pigment (B) and the processability of the resin composition.

<Compatible agent (C)>
The compatibilizer (C) in the present invention contains a polyolefin elastomer. This makes it possible to suppress warpage and shrinkage of the molded product due to the organic pigment (B) and the polyolefin resin (A). It is considered that the interaction of the polyolefin elastomer with the organic pigment (B) weakens the nucleation effect of the organic pigment (B), so that the warp and shrinkage of the polyolefin resin (A) can be suppressed.
Further, by using the polyolefin elastomer, the organic pigment (B) can be stably dispersed without being affected by the hue change due to the compatibilizer, and it is possible to form a molded body in which the hue change is suppressed. Become.
In addition, other compatibilizers may be used in combination.

The polyolefin elastomer is preferably a polymer having an olefin moiety that does not exhibit a melting point in the range of 40 to 200 ° C.
The melting point in the present specification is a value measured using a differential scanning calorimeter "DSC6200" (manufactured by Seiko Instruments, Inc.) under the conditions of a temperature range of 40 to 200 ° C. and a heating rate of 10 ° C./min.

Examples of the olefin moiety of the polyolefin elastomer include α-olefins such as ethylene, propylene and diene. Specific examples of the polyolefin elastomer include α-olefin copolymers and styrene-olefin copolymers. The MFR of the compatibilizer (C) is preferably 1 to 10 g / 10 minutes, more preferably 1 to 5 g / 10 minutes. When the MFR is in the above range, the compatibility with the polyolefin resin (A) is more excellent, which is preferable.

The α-olefin copolymer is produced by polymerizing α-olefins using, for example, a catalyst composed of a transition metal compound and an organoaluminum compound, a so-called Cheegler type catalyst.

Specific examples of α-olefin include propylene, 1-butene, 2-methyl-1-propene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 2-ethyl-1-butene, and the like. 2,3-dimethyl-1-butene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3,3-dimethyl-1-butene, 1-hexene, methyl- 1-hexene, dimethyl-1-pentene, ethyl-1-pentene, trimethyl-1-butene, methylethyl-1-butene, 1-octene, methyl-1-pentene, ethyl-1-hexene, dimethyl-1-hexene , Propylene-1-heptene, methylethyl-1-heptene, trimethyl-1-pentene, propyl-1-pentene, diethyl-1-butene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, etc. Can be mentioned. Of these, α-olefins having 3 to 10 carbon atoms are preferable, and α-olefins having 3 to 8 carbon atoms are more preferable. The more in the above range, the more excellent the compatibility with the polyolefin resin (A).

The styrene-olefin copolymer is a copolymer having a unit derived from olefin and a unit derived from styrene, and can be polymerized and produced under a metal catalyst such as, for example, a Chigra natta catalyst.

Specific examples of the olefin moiety of the styrene-olefin copolymer include monoolefins such as α-olefins such as ethylene, propylene and butene, and diolefins (conjugated diene) such as butadiene and isoprene.

Specific examples of the styrene moiety of the styrene-olefin copolymer include styrene, α-methylstyrene, p-methylstyrene and the like.

The ratio of the olefin moiety of the polyolefin elastomer is preferably 50% by mass or more, more preferably 70% by mass or more and 100% by mass or less, based on 100% by mass of the polyolefin elastomer. When the ratio of olefin is 50% by mass or more, the ratio of styrene is not too large, the compatibility with the polyolefin resin (A) is high, and it is easier to suppress appearance defects such as surface peeling of the molded product. When the ratio of the polyolefin is 100% by mass, the single component having good compatibility with the resin is preferable in the comparison between the mixture and the single component.

The polyolefin elastomer preferably has an acidic functional group because it has a strong interaction with the organic pigment (B). Examples of the acidic functional group include a carboxyl group (—COOH) and a carboxylic acid anhydride group (O = C—O—C = O).

The acid value of the polyolefin elastomer having an acidic functional group is preferably 1 to 30 mgKOH / g, more preferably 5 to 26 mgKOH / g. When the acid value of the polyolefin elastomer is in the above range, the compatibility between the polyolefin elastomer and the organic pigment (B) can be improved.
The acid value in the present invention is a value measured according to JIS K-0070.

The blending amount ratio [(C) / (B)] of the compatibilizer (C) and the organic pigment (B) is preferably 0.05 to 1, and more preferably 0.1 to 0.8. When the blending amount ratio is 0.05 or more, it is excellent in suppressing warpage and shrinkage, and when it is 1 or less, mutual adhesion of the colored resin composition can be further suppressed, and stable supply becomes easy.
Preferably, the blending amount ratio of the polyolefin elastomer and the organic pigment (B) [polyolefin elastomer / (B)] is 0.05 to 1. It is more preferably 0.05 to 0.8, and even more preferably 0.1 to 0.8.

When the organic pigment (B) is a diketopyrrolopyrrole pigment, the polyolefin elastomer is preferably an acid-modified styrene-diene copolymer, and the above combination is most excellent in warpage and shrinkage due to crystallization. can.

Specific examples of polyolefin elastomers include Tuffmer A4085S (Mitsui Chemicals, ethylene / α-olefin copolymer), Excelene FX FX555 (Sumitomo Chemicals, ethylene / 1-hexene copolymer), Toughtec H1052 (Asahi Kasei, styrene butadiene). Copolymer, styrene compound unit content 30% by mass), Tuftec M1911 (manufactured by Asahi Kasei Co., Ltd., acid value: 2 mgKOH / g, maleic anhydride-modified styrene-diene copolymer, styrene compound unit content 20% by mass) Toughtech M1943 (Manufactured by Asahi Kasei Co., Ltd., acid value: 10 mgKOH / g, maleic anhydride-modified styrene-diene copolymer, styrene compound unit content 20% by mass) and the like.

<Arbitrary ingredient>
The colored resin composition of the present invention contains an alkali metal, an alkaline earth metal or a zinc metal soap, a hydrotalcite, a nonionic surfactant, a cationic surfactant, and an anion, as long as the effects of the present invention are not impaired. Additives such as sex surfactants, amphoteric surfactants, antistatic agents, halogen-based, phosphorus-based or metal oxide flame retardants, antioxidants, UV absorbers, fillers, and inorganic to match your preferred hue. It can contain a pigment or the like.

Examples of the inorganic pigment include titanium oxide, calcium carbonate, barium sulfate, zinc sulfide, iron oxide, ultramarine, cobalt blue, nickel titanium yellow, bismuth yellow, carbon black, and pearl pigments.

<< Molded body >>
The molded body is molded using the colored resin composition of the present invention.
The molding method is not particularly limited, and can be obtained by extrusion molding, compression molding, injection molding, blow molding and the like.
The molded body may be formed as it is from a colored resin composition obtained by kneading an organic pigment (B) and a compatibilizer (C) at a temperature at which the polyolefin resin (A) melts, or an organic pigment (an organic pigment (). A masterbatch containing B) in a high concentration may be used, and then the molded product may be molded from a colored resin composition kneaded with a polyolefin resin as a diluted resin at a predetermined magnification at the time of molding the molded product.
Further, the diluted resin at this time may be the same resin as the polyolefin resin (A) constituting the masterbatch or a different resin, but the same resin is preferable.

The content of the polyolefin resin (A) in 100% by mass of the masterbatch is preferably 20% by mass or more, more preferably 30 to 60% by mass. When the blending amount of the polyolefin resin (A) is 20% by mass or more, the processability at the time of masterbatch production becomes better.
The content of the organic pigment (B) in 100% by mass of the masterbatch is preferably 1 to 60% by mass, more preferably 5 to 50% by mass in 100% by mass of the colored resin composition.

The content of the polyolefin resin (A) in 100% by mass of the molded product is preferably 60% by mass or more and 100% by mass or less, and more preferably 90% by mass or more. When the blending amount of the polyolefin resin (A) is 60% by mass or more, it is easy to sufficiently maintain the strength of the molded product.
The content of the organic pigment (B) in 100% by mass of the molded product is preferably 0.01% by mass or more, more preferably 0.1% by mass or more and 1% by mass or less in 100% by mass of the colored resin composition. , 0.3% by mass or more and less than 0.8% by mass is more preferable.

Since the molded body formed from the colored resin composition of the present invention is excellent in suppressing warpage and shrinkage, a beverage cap molded by compression molding (compression molding) or injection molding (injection molding), and a blow. It can be suitably used for a container or the like molded by molding (direct blow, injection blow).
In particular, in the case of injection molding (injection molding), it is possible to obtain a molded product that suppresses shrinkage of the molded product, controls dimensional changes due to coloring, and maintains dimensional stability with high accuracy. preferable.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to Examples. In the examples, "parts" and "%" represent "parts by mass" and "% by mass", respectively, unless otherwise specified.
In addition, the blending amount in the table is a part by mass, and the blank indicates that the blending is not performed.
The method for measuring the melt viscosity of the polyolefin resin (A) and the acid value of the compatibilizer (C) is as follows.

[Melting viscosity of polyolefin resin (A)]
MFR was measured according to JIS (Japanese Industrial Standards) K-7210.
[Acid value of compatibilizer (C)]
The acid value was measured according to JIS K-0070.

The materials used in the examples and comparative examples are listed below.
<Polyolefin resin (A)>
A-1: Hi-Zex 2208J (manufactured by Prime Polymer Co., Ltd., MFR: 5 g / 10 minutes, HDPE)
A-2: Prime Polypro J105G (manufactured by Prime Polymer Co., Ltd., MFR: 9 g / 10 minutes, PP)
A-3: Suntech HD J300 (Made by Asahi Kasei, MFR: 42g / 10 minutes, HDPE)
<Organic pigment (B)>
B-1: Irgazine Yellow 3RLT-N (BASF, P.Y.110, Isoindolenon Yellow)
B-2: Binamon Red 325401 (Heubach, PR254, Diketopyrrolopyrrole Red)
B-3: Pariogen Red K3911HD (BASF, PR.178, Perylene Red)
B-4: Lionol Blue FG7330 (manufactured by Toyo Color Co., Ltd., P.B. 15.3, β-phthalocyanine blue)
<Compatible agent (C)>
[Polyolefin elastomer]
C-1: Toughmer A4085S (manufactured by Mitsui Chemicals, melting point: 66 ° C., ethylene / α-olefin copolymer, olefin moiety 100% by mass)
C-2: Tough Tech H1043 (manufactured by Asahi Kasei Corporation, styrene-diene copolymer, styrene compound unit content 67% by mass, olefin moiety 33% by mass)
C-3: Tough Tech M1943 (manufactured by Asahi Kasei Co., Ltd., acid value: 10 mgKOH / g, maleic anhydride-modified styrene-diene copolymer, styrene compound unit content 20% by mass, olefin moiety 80% by mass)
[Other compatibilizers]
CC-1: High wax NP50605A (manufactured by Mitsui Chemicals, acid value: 61, melting point: 143 ° C, maleic anhydride-modified polyolefin wax)

<Example 1>
99.45 parts of polyolefin resin (A-1), 0.5 part of organic pigment (B-1), and 0.05 part of compatibilizer (C-1) are mixed, and a twin-screw extruder (manufactured by Japan Steel Works, Ltd.) is mixed. ), Extruded at 200 ° C. and granulated to obtain a pellet-shaped colored resin composition (D-1).
Subsequently, 100 parts of the obtained colored resin composition (D-1) was molded by an injection molding machine (manufactured by Toshiba Machinery Co., Ltd.) under the injection conditions described later, and in a constant temperature room at 23 ° C. and 50% RH. The product was stored for 1 day to obtain a plate-shaped molded product 1.

<Examples 2 to 11, Comparative Examples 1 to 4>
Pellet-shaped colored resin compositions (D-2 to 11, 14 to 17) were obtained in the same manner as in Example 1 except that the materials and the blending amounts (parts by mass) shown in Tables 1 and 2 were changed. rice field.
Subsequently, 100 parts of the obtained colored resin composition was molded by an injection molding machine (manufactured by Toshiba Machinery Co., Ltd.) under the injection conditions described later, and stored in a constant temperature room at 23 ° C. and 50% RH for 1 day to plate. Shaped bodies 2 to 11 were obtained.

<Example 12>
77.4 parts of polyolefin resin (A-3), 20 parts of organic pigment (B-2), and 2.6 parts of compatibilizer (C-3) are mixed and put into a twin-screw extruder (manufactured by Japan Steel Works, Ltd.). The mixture was extruded at 200 ° C. and granulated to obtain a pellet-shaped masterbatch (MB-1).
Subsequently, 4 parts of the obtained masterbatch (MB-1) and 100 parts of the polyolefin resin (A-1) were mixed to obtain a colored resin composition (D-12), and an injection molding machine (injection molding machine) was used according to the injection conditions described later. It was molded by Toshiba Machinery Co., Ltd.) and stored in a constant temperature room at 23 ° C. and 50% RH for 1 day to obtain a plate-shaped molded product 12.

<Example 13>
Mix 54.9 parts of polyolefin resin (A-3), 40 parts of organic pigment (B-2), and 5.1 parts of compatibilizer (C-3) into a twin-screw extruder (manufactured by Japan Steel Works, Ltd.). The mixture was extruded at 200 ° C. and granulated to obtain a pellet-shaped masterbatch (MB-2).
Subsequently, 2 parts of the obtained master batch (MB-2) and 100 parts of the polyolefin resin (A-1) were mixed to obtain a colored resin composition (D-13), and an injection molding machine (injection molding machine) was used according to the injection conditions described later. It was molded by Toshiba Machinery Co., Ltd.) and stored in a constant temperature room at 23 ° C. and 50% RH for 1 day to obtain a plate-shaped molded product 12.

[Manufacturing conditions for molded product (plate-shaped molded product)]
The manufacturing conditions for the molded product (plate-shaped molded product) are 20 continuous injection molding at a molding temperature of 220 ° C and a mold temperature of 40 ° C at the time of molding with an injection molding machine (manufactured by Toshiba Machinery Co., Ltd.) for evaluation. Of these, 6 of the 14th to 19th sheets were molded and then stored in a constant temperature room at 23 ° C. and 50 RH for 1 day, and then a plate-shaped molded product was used.
As an evaluation standard, a molded plate (sometimes referred to as “natural”) formed by molding only the polyolefin resin (A) under the same conditions was used.
As a mold for producing a plate-shaped molded product, a mold for producing a plate having a length of 150 mm, a width of 120 mm, and a thickness of 2 mm provided with a 100 mm marked line in the injection direction and the direction perpendicular to the injection direction was used.

<Measurement of shrinkage rate>
Using the obtained 6 molded plates, the distance between the marked lines was measured with a precision caliper, and the average value of the shrinkage rate in the injection direction and the vertical direction was obtained from the value. The formula for calculating the shrinkage difference rate is as follows.

The values of X0 and Y0 in the resin compositions of Examples 12 and 13 were determined by using the polyolefin resin (A-1) which is the main component of the polyolefin resin (A).

Equation (1) ΔMDS = | X1-X0 |
Equation (2) ΔTDS = | Y1-Y0 |
(Note that X1 and Y1 are each molded from a colored resin composition by an injection molding machine and have a length of 150 mm, a width of 120 mm, and a thickness of 2 mm, respectively, in the same direction as the injection direction one day after molding (MD). The shrinkage rate in the direction) and the shrinkage rate in the direction perpendicular to the injection direction (TD).
X0 and Y0 are the same directions (MD direction) as the injection direction one day after molding of a molded product having a length of 150 mm, a width of 120 mm and a thickness of 2 mm, which is molded from the polyolefin resin (A) by an injection molding machine, respectively. The shrinkage rate in, and the shrinkage rate in the direction perpendicular to the injection direction (TD). )

That is, for example, in Example 1, a molded product having a length of 150 mm, a width of 120 mm, and a thickness of 2 mm, which is molded from the resin composition 1 by an injection molding machine, has the same direction (MD direction) as the injection direction one day after molding. ) Is X1 and the shrinkage rate X2 in the direction perpendicular to the injection direction (TD), and is molded from the polyolefin resin (A-1) by an injection molding machine, having a length of 150 mm, a width of 120 mm, and a thickness of 2 mm. The shrinkage rate of the molded product in the same direction (MD direction) as the injection direction one day after molding is X0, and the shrinkage rate in the direction perpendicular to the injection direction (TD) is Y0.

X1: Shrinkage rate of the molded plate 1 in the injection direction = distance between MD direction marked lines after molding mm / 100 mm × 100
Y1: Shrinkage rate in the direction orthogonal to the injection direction of the molded plate 1 = distance between TD direction marked lines after molding mm / 100 mm × 100
X0: Shrinkage rate in the injection direction of natural using only polyolefin resin (A-1) = distance between MD direction marked lines after natural molding mm / 100 mm × 100
Y0: Shrinkage rate in the direction orthogonal to the natural injection direction using only polyolefin resin (A-1) = distance between TD direction marked lines after natural molding mm / 100 mm × 100

(Evaluation of resin composition)
<Bleedability evaluation>
100 g of the colored resin composition was allowed to stand at 60 ° C. for 2 days, and the state of the pellet surface was visually evaluated. If no bleeding substance was confirmed on the pellet surface, it was marked with "○", and if a bleeding substance was clearly confirmed, it was marked with "x".

<Evaluation of reciprocity>
After putting the resin composition in a mentum can having a diameter of 5 cm and a depth of 3 cm, the resin composition was heated in an oven at 60 ° C. for one day with a weight of 1 kg on it. Then, the mixture was allowed to cool to room temperature, the mentum can was removed, and the degree of mutual adhesion of the pellets was evaluated.
If the mutual attachment of pellets could not be confirmed, it was evaluated as "○", if the mutual attachment of pellets was confirmed in a small amount, it was evaluated as "Δ", and if the mutual attachment of pellets was confirmed in half or more, it was evaluated as "×". If the evaluation is "Δ" or higher, it can be used for pellet supply without any problem.

(Evaluation of molded product)
<Warp>
A 2 kg weight was placed on the gate portion of the obtained molded body, and the height raised from the horizontal position was measured. When there was no floating, it was evaluated as "○", when the height was 2 mm or less, it was evaluated as "Δ", and when the height was more than 2 mm, it was evaluated as "×". If it is Δ or more, it is practical.

<Hue>
The L ^* , a ^* , and b ^* values of the molded product were measured using a D-65 (10) standard light source using an image spectrophotometer AU color COLOR7x manufactured by Kurabou (L ^* 1, a ^* 1, b, respectively). ^* 1).
Further, as a standard, a resin composition containing the same type of pigment as the molded product at the same concentration is used except that the compatibilizer (C) is not contained, and the standard molded product is manufactured under the same conditions, and L ^* , a ^* , b ^* values were measured (L ^* 0, a ^* 0, b ^* 0, respectively).
The hue evaluation was performed by calculating the color difference (ΔE ^* ) from the following formula (3).
If ΔE ^* is 0.5 or less, it is evaluated as “⊚”, if it is more than 0.5 and 1 or less, it is evaluated as “◯”, and if it is 1 or more, it is evaluated as “×”.
It can be said that the smaller ΔE ^* is, the less the hue is changed by the compatibilizer, and the organic pigment (B) is stably dispersed.

Equation (3)
△ E ^* = [(L ^* 1-L ^* 0) ² + (a ^* 1-a ^* 0) ² + (b ^* 1-b ^* 0) ² ] ^1/2

<Surface peeling>
Using the obtained molded product, the work of attaching cellophane tape and peeling it off at once was performed on each of the 6 molded products at 4 locations, and the presence or absence of peeling was confirmed. The total number of peeling points is totaled, and if the total number of peeling points is 5 or less, the surface peeling property is considered to be good, "○", if it is 6 or more and less than 10 points, "△", and if it is 10 or more, the surface peeling is performed. It was marked as "x" because of poor sex. If it is Δ or more, it is practical.

As shown in Tables 3 and 4, the colored resin composition (D) containing the polyolefin resin (A), the organic pigment (B), and the compatibilizer (C) is the compatibilizer (C). A colored resin composition which is a polyolefin elastomer and further has a ΔMDS represented by the formula (1) of 0.35% or less and a ΔTDS represented by the formula (2) of 0.35% or less can be used to determine the hue of the pigment. It was confirmed that a molded product in which warpage and shrinkage were suppressed without impairing bleeding property, surface peeling property, and mutual adhesion could be obtained.

Claims (5)

A colored resin composition containing a polyolefin resin (A), an organic pigment (B), and a compatibilizer (C).
The compatibilizer (C) contains a polyolefin elastomer and contains
A colored resin composition having a ΔMDS represented by the following formula (1) of 0.35% or less and a ΔTDS represented by the following formula (2) of 0.35% or less.

Equation (1) ΔMDS = | X1-X0 |
Equation (2) ΔTDS = | Y1-Y0 |

(Note that X1 and Y1 are each in the same direction as the injection direction one day after molding of a molded product having a length of 150 mm, a width of 120 mm and a thickness of 2 mm, which is molded from a colored resin composition by an injection molding machine. The shrinkage rate in the MD direction) and the shrinkage rate in the direction perpendicular to the injection direction (TD).
X0 and Y0 are the same directions (MD direction) as the injection direction one day after molding of a molded product having a length of 150 mm, a width of 120 mm and a thickness of 2 mm, which is molded from the polyolefin resin (A) by an injection molding machine, respectively. ), And the shrinkage rate in the direction perpendicular to the injection direction (TD). ) The colored resin composition according to claim 1, wherein the organic pigment (B) contains at least one selected from the group consisting of an azo pigment, a quinacridone pigment, a perylene pigment, an isoindolinone pigment, and a diketopyrrolopyrrole pigment. The colored resin composition according to claim 1 or 2, wherein the ratio of the olefin moiety of the polyolefin elastomer is 50% by mass or more. The colored resin composition according to any one of claims 1 to 3, wherein the compounding ratio [(C) / (B)] of the organic pigment (B) and the compatibilizer (C) is 0.05 to 1. A molded product formed from the colored resin composition according to any one of claims 1 to 4.