JPH08319366A - Foaming colored resin particle and production thereof - Google Patents

Abstract

PURPOSE: To obtain foaming colored resin particles which comprise a styrene resin, an aromatic hydrocarbon, a specific dye and a foaming agent and are useful as a colored transportation or package container because of their excellent tinting uniformity, dyeing fastness, moldability and the like. CONSTITUTION: The objective foaming colored resin particles contain, (A) a styrene resin, for example, a graft polymer prepared by grafting 0.5-5 pts.wt. of a styrene monomer to 1 pt.wt. of an olefin resin, (B) an aromatic hydrocarbon such as benzene, toluene, xylene or ethylbenzene, (C) an anthraquinone or perinone dye having a solubility of more than 0.1g/100ml of the component B, and (D) a foaming agent such as propane, (iso)butane, (cyclo)pentane.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to colored expandable particles made of styrene resin and a method for producing the same. In particular, the present invention relates to expandable particles capable of easily producing a foamed molded product of styrene resin uniformly colored without uneven color and a method for producing the same.

[0002]

2. Description of the Related Art Styrenic resin foam moldings are widely used as containers for transportation and packaging. Among them, large-sized foamed molded products such as a container for machine parts and a lid for a tank are made via expandable particles. The expandable particles are particles containing a foaming agent such as butane and pentane and having a particle size of 0.1 to 10 mm. Since the expandable particles have the property of easily expanding when they are contacted with steam and heated, they are once heated in the form of particles to be expanded into pre-expanded particles, and the pre-expanded particles are used as a molding die. A large-sized foamed molded body has been produced by a method of putting it in and heating it again, and fusing particles in a mold to form a molded body.

The foamed molded product is often colored in gray color because it has the advantage that stains are not noticeable when it is colored in gray color. Carbon black has heretofore been used as a colorant for producing gray colored expandable particles. To make expandable particles containing carbon black, it is known to attach carbon black to particles when impregnating a styrene resin with a foaming agent, but this does not allow the carbon black to penetrate into the inside of the particles. . Therefore, the carbon black-containing particles thus obtained, when trying to foam it,
Not only was carbon black attached to the surface of the foaming device to contaminate the device, but also a foam without uneven color could not be obtained.

Further, in order to produce expandable particles made of a gray color styrene resin, carbon black is dispersed in a styrene monomer, and this is suspension polymerized in an aqueous medium, and in the process, a foaming agent is used. A method of press-fitting is known.
However, in this method, not only is carbon black transferred from the styrene-based monomer into the aqueous medium to lose the carbon black, but also the treatment of the aqueous medium containing carbon becomes troublesome, and the suspension polymerization causes carbon black. There was the disadvantage that it was blocked due to black resulting in delayed or incomplete polymerization. Further, when the expandable particles thus obtained are foamed, there is a drawback that carbon black stains the foaming machinery and equipment and it takes time to clean the foaming particles (JP-A-62-109835).

Generally, several methods are known for producing colored expandable resin particles. One of them is a method of dryly mixing a dye or a pigment with the expandable resin particles which already contain the foaming agent. However, in this method, the adhesion of the dye or pigment to the resin particles is weak, and the dye or pigment easily separates from the resin particles, and thus it is difficult to color the dye or pigment to a desired concentration, and the machinery used for foaming is contaminated. However, if the concentration is further increased, mutual fusion of the resin particles is hindered and a good molded product cannot be produced.

Further, in the above method, there is a method of coating the surface of the resin particles with a dye or a pigment in order to prevent the dye or the pigment from coming off. In this method, however, the inside is evenly colored. However, there is a drawback in that it is complicated and the coating process is extra.

As another method for producing expandable colored resin particles, resin particles are dispersed in an aqueous medium containing a dispersant and a surfactant, and aromatic hydrocarbon and a pigment are added thereto and stirred. While heating, the method of press-fitting a foaming agent is known. However, in this method, it is necessary to disperse the resin particles in the aqueous medium and press-fit the foaming agent, so that a large facility is required, and it is necessary to wash and dehydrate after pressurizing the foaming agent, resulting in high cost. ,
There is a disadvantage that.

As another method for producing expandable colored resin particles, there is a method of kneading a dye or a pigment to color the resin particles when the resin particles are manufactured, and then press-fitting a foaming agent.
However, in this method, since it is necessary to use an extruder or the like to knead the dye or pigment, it takes time to change the color, and a large amount of resin is lost due to the color change, which is economical. There is a disadvantage that it is disadvantageous. As described above, none of the methods heretofore proposed for producing expandable colored resin particles has drawbacks and is unsatisfactory.

Japanese Unexamined Patent Publication (Kokai) No. 2-247234 discloses a method for producing expandable colored resin particles in which the above-mentioned drawbacks are improved. The production method is such that a dye-dispersed emulsion in which at least a part of the dye is dissolved is prepared, on the other hand, resin particles are dispersed in an aqueous medium to form a suspension, and the suspension is mixed with the dye dispersion. A foaming agent is added, and a dye and a foaming agent are impregnated into resin particles to form expandable colored resin particles. However, in this method, it is necessary to use a dye as an emulsion, and for this purpose, a dye solution using an organic solvent and an aqueous solution in which an emulsifier such as polyvinyl alcohol is dissolved are prepared, and these are mixed and emulsified. The disadvantage is that it requires a complicated process that must be done.

[0010]

SUMMARY OF THE INVENTION The present invention is intended to obtain expandable colored particles made of a styrene resin which does not have the above-mentioned drawbacks. That is, the present invention is uniformly colored without uneven color, less likely to stain the machine tool during the production and foam molding of the expandable particles, and even if the stain is easy to clean the machine tool, In addition, it is an object of the present invention to provide expandable particles that can efficiently and easily obtain colored expandable particles, and that foams well and gives a good expanded product. The present invention also aims to provide a method for producing such expandable particles.

[0011]

SUMMARY OF THE INVENTION The inventor first conceived of not using carbon black to gray a styrenic resin, but instead using a dye soluble in aromatic hydrocarbons. . Then, as a result of various experiments, 0.1 g was added to the aromatic hydrocarbon as a dye.
/ Use an anthraquinone or perinone type with a solubility of 100 ml or more and use three colors of red, blue and orange or three colors of blue, purple and orange or a combination of three colors of purple, red and orange as colors It was found that the styrene resin can be colored in gray when used. Further, when using this dye, if a small amount of an aromatic hydrocarbon having the above-mentioned solubility is used for these dyes, the dye penetrates well into the styrene-based resin, and the styrene-based resin is easily and uniformly distributed. I found that it can be dyed.

As a result of further experiments, the inventor found that
It has been found that the above-mentioned findings obtained when coloring the styrene resin in gray color can be applied to the case of coloring other than gray color by using a dye. That is, when anthraquinone-based or perinone-based dyes having a solubility of 0.1 g / 100 ml or more in aromatic hydrocarbons are used alone or in combination of two or more, the styrene resin is easily and uniformly colored. In addition to being able to do so, there is no hindrance to imparting foamability, and there is little contamination of machinery and equipment during the production and foaming of expandable colored particles, and cleaning of machinery and equipment is easy even if it contaminates. Found. The present invention has been completed based on such knowledge.

In particular, particles of a graft polymer obtained by graft-polymerizing a styrene-based monomer onto an olefin-based resin are used as the styrene-based resin, and the particles are colored with the anthraquinone-based or perinone-based dye as described above. Then,
Even if the particles are not dispersed in the aqueous medium, it is advantageous because the particles can be easily and uniformly colored, but if the particles are dispersed and colored in the aqueous medium, it can be more reliably and uniformly colored, which is advantageous. found.

In the present invention, a styrene resin is used as an aromatic hydrocarbon, and 0.1 g / 100 m of the aromatic hydrocarbon is used.
The present invention relates to expandable colored resin particles comprising an anthraquinone-based or perinone-based dye having a solubility of 1 or more and a foaming agent. The anthraquinone-based or perinone-based dye means that anthraquinone-based or perinone-based dye is used alone or in combination of two or more kinds.

Further, according to the present invention, the styrene resin is put in a pressure tight hermetic mixer, and the aromatic hydrocarbon and anthraquinone having a solubility of 0.1 g / 100 ml or more in the aromatic hydrocarbon are placed in the mixer. The present invention relates to a method for producing expandable colored resin particles, which comprises adding a system dye or a perinone dye, heating the mixture while stirring, and pressurizing a foaming agent into the mixture.

In the present invention, an anthraquinone dye or a perinone dye is selected from many colorants and used for coloring the styrene resin. The reason is that these dyes are fast and can dye styrene resins firmly. These dyes can also be used as a mixture. At least 3 for gray coloring
It is necessary to use a mixture of colors. In that case, the three colors are red, blue and orange, or blue, purple and orange, or purple, red and orange. All of these three colors are oil-soluble, and it is required that 0.1 g or more of them be dissolved in 100 ml of aromatic hydrocarbon such as benzene. The mixing ratio of the three colors is 0.003 to 0.015 part by weight of blue to 100 parts of resin, 0.005 to 0.025 part of orange, and 0.0 of red or purple.
It is preferable to set it to 02 to 0.025 part.

The anthraquinone dye is a dye containing an anthraquinone skeleton in the dye molecule. It can be determined, for example, by selecting from the series sold by Mitsubishi Chemical Co. under the name Diaresin, those noted as anthraquinone series.
For example, dialyzin blue J can be used as the purple dye, and dialyzin blue P can be used as the blue dye. These dyes are well soluble in aromatic hydrocarbons, especially in toluene, and 0.1g / 100ml
The above solubility is shown.

The perinone dye is a dye containing a perinone skeleton. It can be determined, for example, by selecting from the series sold by Mitsubishi Chemical Co. under the name Diaresin, those noted as perinone series. For example, as orange, those sold as DIARESIN ORANGE HS by Mitsubishi Chemical Corporation can be used. This dye also dissolves well in aromatic hydrocarbons, especially in toluene, and is 0.1g / 100m.
It shows a solubility of 1 or more.

In the present invention, a styrene resin is used as the resin. The styrene resin is not limited to a homopolymer of a styrene monomer, but includes a copolymer thereof.
The styrene-based monomer contains styrene derivatives such as α-methylstyrene, vinyltoluene, and chlorostyrene in addition to styrene. As the copolymer, a copolymer of styrene and acrylonitrile, butadiene, methyl methacrylate or the like can be used. Further, as a special type of copolymer, it is possible to use a graft polymer obtained by graft-polymerizing a styrene-based monomer to an olefin-based resin as described above. The proportion of the graft polymerization is preferably 0.5 to 5 parts by weight of the styrene-based monomer with respect to 1 part by weight of the olefin resin.

In the present invention, an aromatic hydrocarbon is used to color the above resin with the above dye. As the aromatic hydrocarbon, benzene, toluene, xylene, ethylbenzene or the like can be used. The amount of the aromatic hydrocarbon used is 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the resin.

The mixture of resin, dye and aromatic hydrocarbon is
First, the resin is put into a mixer, and then the dye and the aromatic hydrocarbon are mixed. The dye and aromatic hydrocarbon may be in any order. Further, this mixing can be carried out by a dry method or a wet method. The dry method is a method in which a resin, a dye, an aromatic hydrocarbon and a foaming agent are put in a mixer, and the mixture is heated while being stirred to allow the dye, the aromatic hydrocarbon and the foaming agent to penetrate into the resin. is there. On the other hand, wet means that a resin, a dye, an aromatic hydrocarbon and a foaming agent are dispersed in an aqueous medium, and the dispersion is heated while being stirred so that the dye, the aromatic hydrocarbon and the foaming agent are heated. Is a method of infiltrating into the resin.

As the foaming agent, a foaming agent which has been used for foaming a styrene resin can be used. The foaming agent is an aliphatic or cycloaliphatic hydrocarbon having a boiling point lower than the softening point of the styrene resin.
For example, the ones belonging to the aliphatic hydrocarbon are:
Propane, isobutane, n-butane, pentane, etc., and cyclopentane, cyclohexane, etc. belong to the cycloaliphatic hydrocarbons. These foaming agents can be used alone or in combination. The foaming agent is contained in an amount of 2 parts by weight or more based on 100 parts by weight of the styrene resin.

As described above, the styrenic foamable resin colored in gray color or other colors can be obtained.

When a graft polymer obtained by graft-polymerizing a styrene-based monomer with an olefin-based resin is used as the styrene-based resin, the graft polymer is manufactured to give coloring and foamability. You can To do that,
First, disperse the olefin resin particles in an aqueous medium,
A styrene-based monomer containing a polymerization catalyst is added to this dispersion, the styrene-based monomer is absorbed by the olefin-based resin particles, and the absorbed styrene-based monomer is graft-polymerized with the olefin-based resin to be grafted. Polymer particles are obtained. Then, the graft polymer particles are mixed with anthraquinone-based or perinone-based dye mixture consisting of three colors of red, blue and orange or three colors of blue, purple or orange or three colors of purple, red and orange, and aromatic carbonization. Hydrogen is added, and the aromatic hydrocarbon and the dye are permeated into the polymer particles by a dry method or a wet method, and a foaming agent is pressed into the polymer particles. Thus, the expandable particles of the styrene resin colored in gray can be obtained.

[0025]

According to the present invention, since the dye having the solubility of 0.1 g / 100 ml or more in the aromatic hydrocarbon is used, unlike the case where the carbon black is used, the dye reaches the inside of the styrene resin particles. It is easy to penetrate, so that the inside of the particles can be uniformly colored. Also, 0.
The graft polymer obtained by graft-polymerizing 5 to 5 times the amount of the styrene-based monomer can have a lower impregnation temperature than the styrene homopolymer. This means that the blowing agent can be impregnated at a temperature at which the polymers do not block each other even in the dry method, and it is not always necessary to disperse the styrene resin in the aqueous medium, and the operation can be performed easily because it can be carried out in the so-called dry method. The manufacturing cost is also low. Further, if it is carried out by a so-called wet method, it can be more surely and uniformly colored. Further, a foamed molded product can be produced without contaminating the device for producing expandable particles and the device for foaming. Further, since anthraquinone type or perinone type dye is used as the dye, the dyeing is fast. In particular, in the case of coloring in gray color, since red, blue and orange, or blue, purple and orange, or purple, red and orange are mixed and used, various shades of gray can be obtained. Moreover, since the above dye does not hinder the press-in of the foaming agent or the foaming of the resin, by using the expandable particles, it is possible to easily form a foam uniformly colored in a desired color. it can. In particular, it is advantageous to use a resin obtained by graft-polymerizing a styrene-based resin on an olefin-based resin, because a colored foamed molded article having a high impact resistance without color unevenness can be easily obtained.

The advantages of the present invention will be specifically described below with reference to Examples and Comparative Examples. In the following, simply "parts" means "parts by weight". In addition, the term "solubility" refers to a dye, which is soluble in 100 ml of toluene, expressed in grams.

[0027]

Example 1 In this example, polyethylene resin was used as a resin in which styrene was graft-polymerized, and a dye was allowed to permeate the graft polymer particles by a dry method, and then butane was injected as a foaming agent to form a foaming agent. The particles were obtained. The details are as follows.

First, a graft polymer was prepared as follows. In an autoclave with an internal volume of 100 liters, 100 parts of pure water as an aqueous medium, 0.4 parts of magnesium pyrophosphate
A mixture of 5 parts and 0.02 part of sodium dodecylbenzenesulfonate was added, 30 parts of polyethylene particles (trade name: Yucaron HE60 manufactured by Mitsubishi Chemical Co., Ltd.) was added, and the mixture was stirred at a rotation speed of 250 rpm and suspended in an aqueous medium. did.

Separately, 0.3 part of benzoyl peroxide as a polymerization catalyst, 0.01 part of t-butyl peroxybenzoate, and 0.25 part of dicumyl peroxide as a crosslinking agent were added to 70 parts of a styrene monomer. The solution was dissolved to prepare a monomer solution, and this solution was added to the above-mentioned aqueous medium, absorbed by polyethylene particles, and maintained at a temperature of 85 ° C. for 4 hours to carry out polymerization. Then, the temperature was raised to 143 ° C. and the temperature was maintained for 3 hours to complete the polymerization, and then the mixture was cooled to obtain graft polymer particles.

Next, 100 parts of the particles of the above-mentioned graft polymer were put into a pressure-tight rotary mixer having an internal volume of 40 liters, and an anthraquinone dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Blue) was used as a blue colorant. P, solubility 4.7
0.03 part (g / 100 ml), and the mixer was closed and rotated. While rotating the mixer, 1.5 parts of toluene was added thereto, and 14 parts of butane as a foaming agent was further press-fitted. Further, while rotating the mixer, mixing was carried out at a temperature of 70 ° C. for 3 hours to permeate the dye and the foaming agent. Then, it cooled and the expandable particle colored blue was obtained.

The expandable particles were evenly colored in blue. Also, the inside of the above mixer was hardly colored blue.

The expandable particles thus obtained have a bulk ratio of 55.
After double prefoaming, blue foamed particles with almost no unevenness of color of 0.05% were obtained. After leaving the foamed particles at room temperature for 24 hours, 400 × 30
It was placed in a molding die having a size of 0 × 100 mm, steam with a gauge pressure of 0.5 kg / cm ² was introduced into the die for 1 minute to cause foaming, and then cooling was performed for 30 minutes to obtain a foamed molded body.
When this foamed molded product was placed in a drying chamber at 50 ° C. and dried for 1 day, the foamed particles were well fused to each other, and were blue and had good color uniformity and little unevenness. Here, the ratio of color unevenness is calculated as follows. First, the total number of foam particles appearing on the surface of the molded product is counted. After that, the number of foam particles having a dark or light color on the surface of the molded product is counted. Percentage of color unevenness = (the number of foam particles with dark or light color on the surface of the molded product) / (the total number of foam particles on the surface of the molded product) x 100 (%)

[0033]

Example 2 This example was carried out in exactly the same manner as in Example 1 except that only the dye was changed.

The dye used was 0.03 part of an anthraquinone type dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Blue K, solubility 0.12 g / 100 ml) as a blue dye.

The expandable particles obtained were uniformly colored blue with no color unevenness. The inside of the mixer was hardly colored blue. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was 0.07%.
As a result, blue foamed particles which are hardly observed in the above are obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and a blue foam having no color unevenness was obtained.

[0036]

EXAMPLE 3 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was 0.03 part of anthraquinone type dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Blue LR, solubility 1.72 g / 100 ml) as a blue dye.

The expandable particles obtained were uniformly colored blue with no color unevenness. The inside of the mixer was hardly colored blue. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was 0.05%.
As a result, blue foamed particles which are hardly observed in the above are obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and a blue foam having no color unevenness was obtained.

[0039]

Example 4 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was 0.03 part of anthraquinone type dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Blue J, solubility 2.1 g / 100 ml) as a purple dye.

The expandable particles obtained were uniformly colored in blue-violet without uneven color. Further, the inside of the mixer was scarcely colored bluish purple. When the expandable particles obtained were pre-expanded in the same manner as in Example 1, the color unevenness was 0.0.
At 3%, bluish purple foamed particles which were hardly observed were obtained.
Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. The particles were firmly fused to each other to obtain a blue-violet foamed product having no color unevenness.

[0042]

[Embodiment 5] This embodiment is carried out in exactly the same manner as in Embodiment 1, except that only the dye is changed.

The dye used was 0.03 part of anthraquinone type dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Blue G, solubility 0.45 g / 100 ml) as a purple dye.

The expandable particles obtained were uniformly colored in blue-violet without uneven color. Further, the inside of the mixer was scarcely colored bluish purple. When the expandable particles obtained were pre-expanded in the same manner as in Example 1, the color unevenness was 0.0.
At 5%, bluish purple foamed particles which were hardly observed were obtained.
Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. The particles were firmly fused to each other to obtain a blue-violet foamed product having no color unevenness.

[0045]

Example 6 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was 0.03 part of an anthraquinone type dye (manufactured by Mitsubishi Chemical Corporation, Diaresin Red S, solubility 0.89 g / 100 ml) as a red dye.

The expandable particles obtained were uniformly colored in red with no color unevenness. Further, the inside of the mixer was hardly colored red. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was 0.03%.
As a result, red foamed particles which were hardly observed in the above were obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and a red foam having no color unevenness was obtained.

[0048]

Example 7 This example was carried out in exactly the same manner as in Example 1 except that only the dye was changed.

The dye used was a perinone type dye as a red dye (manufactured by Mitsubishi Kagaku Co., Ltd., Dialesin Red A, solubility 0.
37 g / 100 ml) 0.03 part.

The expandable particles obtained were uniformly colored in red without uneven color. Further, the inside of the mixer was hardly colored red. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was 0.07%.
As a result, red foamed particles which were hardly observed in the above were obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and a red foam having no color unevenness was obtained.

[0051]

Example 8 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was 0.03 part of anthraquinone type dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Red Z, solubility 0.11 g / 100 ml) as a red dye.

The expandable particles obtained were uniformly colored in red with no color unevenness. Further, the inside of the mixer was hardly colored red. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was 0.07%.
As a result, red foamed particles which were hardly observed in the above were obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and a red foam having no color unevenness was obtained.

[0054]

Example 9 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was 0.03 part of anthraquinone dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Orange G, solubility 0.70 g / 100 ml) as an orange dye.

The expandable particles obtained were uniformly colored orange with no color unevenness. Further, the inside of the mixer was hardly colored orange. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, orange-colored expanded particles having a color unevenness of 0.04% and hardly observed were obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and an orange foam having no color unevenness was obtained.

[0057]

Example 10 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was a perinone-based dye as an orange dye (manufactured by Mitsubishi Chemical Co., Ltd., Dialesin Orange HS,
Solubility 0.33 g / 100 ml) 0.03 part.

The expandable particles obtained were uniformly colored orange without uneven color. Further, the inside of the mixer was hardly colored orange. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, orange-colored expanded particles having a color unevenness of 0.02% and hardly observed were obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and an orange foam having no color unevenness was obtained.

[0060]

[Embodiment 11] This embodiment is carried out in exactly the same manner as in Embodiment 1, except that only the dye is changed.

The dye used was 0.015 part of the one used in Example 1 (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Blue P),
It is a mixture with 0.015 parts used in Example 7 (manufactured by Mitsubishi Chemical Co., Ltd., Dialesin Red A).

The expandable particles obtained were uniformly purple with no color unevenness. Further, the inside of the mixer was hardly colored purple. The expandable particles thus obtained were pre-expanded in the same manner as in Example 1 to obtain purple expanded particles having a color unevenness of 0.06% and hardly observed. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, a purple foamed product in which the particles were firmly fused and had no color unevenness was obtained.

[0063]

EXAMPLE 12 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was 0.017 parts used in Example 3 (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Blue LR) and 0.017 parts used in Example 9 (manufactured by Mitsubishi Chemical Co., Diaresin Orange G). It is a mixture with 0.013 parts.

The expandable particles obtained were uniformly green with no color unevenness. Further, the inside of the mixer was hardly colored green. The expandable particles thus obtained were pre-expanded in the same manner as in Example 1 to obtain green expanded particles with a color unevenness of 0.05% which was hardly recognized. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, a green foamed product in which the particles were firmly fused and color unevenness was obtained was obtained.

[0066]

EXAMPLE 13 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was the one used in Example 4 as a purple dye (Made by Mitsubishi Kagaku Co., Ltd., Diaresin Blue J).
0.011 parts, 0.007 parts of those used in Example 1 as a blue dye (manufactured by Mitsubishi Chemical Co., Ltd., Dialesin Blue P), and those used in Example 10 as an orange dye (manufactured by Mitsubishi Chemical Co., Ltd., 0.013 parts of DIARESIN ORANGE HS).

The expandable particles obtained had a uniform gray color without color unevenness. Further, the inside of the mixer was scarcely colored. The expandable particles thus obtained were pre-expanded in the same manner as in Example 1 to obtain gray-colored expanded particles having a color unevenness of 0.04% and hardly recognized. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, a gray-colored foamed product in which the particles were firmly fused and color unevenness was obtained was obtained.

[0069]

EXAMPLE 14 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was the one used in Example 2 as a blue dye (Made by Mitsubishi Chemical Co., Ltd., Diaresin Blue K).
0.015 parts, 0.005 parts used as a red dye in Example 6 (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Red S), and 0.005 parts used as an orange dye in Example 10 (manufactured by Mitsubishi Chemical Co., 0.013 parts of DIARESIN ORANGE HS).

The expandable particles obtained were uniformly colored in gray with no color unevenness. Also, the inside of the mixer was hardly colored. The expandable particles thus obtained were pre-expanded in the same manner as in Example 1 to obtain gray-colored expanded particles having a color unevenness of 0.04% and hardly recognized. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and a gray foam having no color unevenness was obtained.

[0072]

EXAMPLE 15 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was the one used in Example 3 as a blue dye (Mitsubishi Resins Co., Ltd., Diaresin Blue LR).
0.016 parts, 0.005 parts used in Example 8 as a red dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Red Z), and those used in Example 9 as an orange dye (manufactured by Mitsubishi Chemical Co., Mixture with 0.014 parts of DIARESIN ORANGE G).

The expandable particles obtained had a uniform gray color without color unevenness. Further, the inside of the mixer was scarcely colored. The expandable particles thus obtained were pre-expanded in the same manner as in Example 1. As a result, gray-colored expanded particles having a color unevenness of 0.05% and hardly observed were obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, a gray-colored foamed product in which the particles were firmly fused and color unevenness was obtained was obtained.

[0075]

Example 16 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was the one used in Example 5 as a purple dye (Made by Mitsubishi Kagaku Co., Ltd., Diaresin Blue G).
0.013 parts and those used in Example 6 as red dyes (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Red S) 0.003 parts and those used in Example 10 as orange dyes (manufactured by Mitsubishi Chemical Co., Diaresin) Orange HS) 0.013 parts.

The expandable particles obtained were uniformly colored in gray without uneven color. Also, the inside of the mixer was hardly colored. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, gray-colored expanded particles having a color unevenness of 0.06% and hardly recognized were obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, the particles were firmly fused and a gray foam having no color unevenness was obtained.

[0078]

Example 17 This example was carried out in exactly the same manner as in Example 1 except that the dye was changed.

The dye used was the one used in Example 1 as a blue dye (Made by Mitsubishi Chemical Co., Ltd., Diaresin Blue P).
0.015 parts and 0.005 parts of red dye used in Example 7 (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Red A) and 0.005 parts of orange dye used in Example 10 (manufactured by Mitsubishi Chemical Co., Ltd., Dia Resin orange HS) 0.011 part.

The expandable particles obtained had a uniform gray color without color unevenness. Further, the inside of the mixer was scarcely colored. When the obtained expandable particles were pre-expanded in the same manner as in Example 1, gray-colored expanded particles having a color unevenness of 0.06% and hardly recognized were obtained. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. As a result, a gray-colored foamed product in which the particles were firmly fused and color unevenness was obtained was obtained.

[0081]

Example 18 This example was carried out in much the same way as Example 13 except that the dye was permeated into the graft polymer by the wet method. The details are as follows.

In an autoclave having an internal volume of 10 liters, 100 parts of water and sodium dodecylbenzenesulfonate (0.1 part) were added.
And 03 parts to make an aqueous medium, and 100 parts of the graft polymer particles obtained in Example 1 are added thereto and dispersed by stirring. Then, the same three kinds of dyes used in Example 1 as coloring agents are mixed in the same proportion. Was mixed and added, and 1.5 parts of toluene was added and the mixture was stirred and dispersed. Then, the autoclave was sealed and 14 parts of butane as a foaming agent was press-fitted therein while continuing stirring. Then, the aqueous dispersion was heated to 70 ° C. and kept at this temperature for 3 hours with stirring to allow the dye and the foaming agent to penetrate into the resin particles. Then, it was cooled to obtain gray expandable particles.

The expandable particles were uniformly colored in gray with no color unevenness. Also, the inside of the autoclave was scarcely colored.

The expandable particles thus obtained were added to a bulk ratio of 55.
When pre-expanded twice, gray-colored expanded particles having almost no unevenness of color of 0.03% were obtained. A foam molded article was obtained in the same manner as in Example 1 using the expanded particles. The foamed molded article was of good quality because the foamed particles were strongly fused to each other and had a gray color and little color unevenness.

[0085]

[Comparative Example 1] A monoazo dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Brown A, solubility 4.9 g /
The same procedure as in Example 1 was carried out using 0.03 part of 100 ml).

The obtained expanded beads were colored orange and had color unevenness, and the inside of the mixer was scarcely colored orange. When the expanded beads were pre-expanded in the same manner as in Example 1, the color unevenness was large at 14%. Using the expanded particles, a foamed molded product was further prepared in the same manner as in Example 1. The particles were well fused, but the color unevenness was large and the foamed product was not good.

[0087]

[Comparative Example 2] In this comparative example, a red dye was used as a monoazo dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Red H, solubility: 0.
(02 g / 100 ml) was carried out in the same manner as in Example 1.

The expandable particles obtained had uneven color, and the inside of the mixer was strongly colored red. When the expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was large at 1.2%. When the foamed particles were used to form a foamed molded product in the same manner as in Example 1, the particles were well fused, but the color unevenness was large and the red color was strongly adhered to the molding die.

[0089]

[Comparative Example 3] In this comparative example, a purple dye, anthraquinone type dye (manufactured by Mitsubishi Chemical Corporation, Violet D, solubility 0.
(04 g / 100 ml) was carried out in the same manner as in Example 1.

The expandable particles obtained were colored purple and had color unevenness, and the inside of the mixer was hardly colored purple. When the expanded beads were pre-expanded in the same manner as in Example 1, the color unevenness was large at 7%. Using the expanded particles, a foamed molded product was further prepared in the same manner as in Example 1. The particles were well fused, but the color unevenness was large and the foamed product was not good.

[0091]

[Comparative Example 4] In this comparative example, a blue dye used in Example 1 (manufactured by Mitsubishi Chemical Co., Ltd., Dialesin Blue P)
The same procedure as in Example 1 was carried out using a mixture of 0.018 part and 0.012 part of the red dye used in Comparative Example 2 (manufactured by Mitsubishi Chemical Corporation, Diaresin Red H).

The expandable particles obtained were uniformly purple with no color unevenness, but the interior of the mixer was strongly colored red. When the expandable particles were pre-expanded in the same manner as in Example 1, color unevenness of 0.05% was hardly recognized. When the foamed particles were used to form a foamed molded product in the same manner as in Example 1, the moldability was good, but the red color strongly adhered to the molding die.

[0093]

Comparative Example 5 In this comparative example, anthraquinone dyes were used as the purple and blue dyes, but a monoazo dye was used as the orange dye, and the same procedure as in Example 1 was carried out.

As the dyes used, the anthraquinone dyes used in Example 13 were used for the purple and blue dyes, respectively.
13 parts and 0.008 parts were used, but 0.011 parts of a monoazo dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Brown A, solubility 4.9 g / 100 ml) was used as an orange dye, and these were mixed. It was done.

The expandable particles thus obtained were colored in gray and had color unevenness, and the inside of the mixer was scarcely colored. When the expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was large at 5%. Using the expanded particles, a foamed molded product was further prepared in the same manner as in Example 1. The particles were well fused, but the color unevenness was large and the foamed product was not good.

[0096]

Comparative Example 6 In this comparative example, an anthraquinone dye was used for the blue dye, a perinone dye was used for the orange dye, and a monoazo dye was used for the red dye.
It carried out like Example 1.

The dyes used were blue and orange dyes, and the anthraquinone dye used in Example 17
0.015 parts and 0.013 parts of perinone dyes respectively
Although used in a ratio with parts, 0.003 parts of a monoazo dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Red H, solubility 0.02 g / 100 ml) was used as a red dye, and these were mixed.

The expandable particles obtained were uniformly gray with no color unevenness, but the interior of the mixer was strongly colored red. When the expandable particles were pre-expanded in the same manner as in Example 1, color unevenness of 0.04% was hardly recognized. Using the expanded particles, Example 1 was further used.
When a foamed molded product was obtained in the same manner as described above, the moldability was good, but red was strongly adhered to the mold.

[0099]

COMPARATIVE EXAMPLE 7 In this comparative example, the blue and orange dyes used were the dyes used in Example 17, but a purple dye, which was an anthraquinone dye but had a low solubility in toluene, was used. The same procedure as in Example 1 was performed.

The dyes used were the same as those used in Example 17 for the blue and orange dyes, respectively.
Parts and 0.013 parts, and 0.008 parts of anthraquinone type dye (manufactured by Mitsubishi Chemical Co., Ltd., Diaresin Violet D, solubility 0.04 g / 100 ml) as a purple dye, and these are mixed.

The expandable particles obtained were colored in gray and had unevenness in color, and the inside of the mixer was colored in purple.
When the expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was large at 2%. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. The particles were well fused and the moldability was good, but the color unevenness was large and a good foamed product was obtained. I couldn't say.

[0102]

[Comparative Example 8] In this comparative example, a pigment (manufactured by Mitsubishi Kasei Hoechst, Dianics Red RE) was used in place of the dye, and
The same procedure as in Example 1 was carried out using 5 parts.

The expandable particles obtained were colored orange and had uneven color. The inside of the mixer was not colored orange. When the expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was 16%, which was large. Using the expanded particles, a foamed molded product was further prepared in the same manner as in Example 1. The particles were well fused, but the color unevenness was large and the foamed product was not good.

[0104]

Comparative Example 9 In this comparative example, a dye and a pigment are used,
It carried out like Example 1.

The dye used was the one used in Example 1 as a blue dye (Mitsubishi Resins Co., Ltd., Dialesin Blue P).
0.015 parts and the one used in Example 6 as a red dye (Mitsubishi Resins Co., Ltd., Diaresin Red S) 0.004
Parts, and 0.023 parts as a pigment (manufactured by Mitsubishi Kasei Hoechst Co., Ltd., Dianics Red RE) are used, and these are mixed.

The expandable particles obtained were colored in gray and had uneven color. The inside of the mixer was not colored. When the expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was 8% and large. Using the expanded particles, a foamed molded product was further prepared in the same manner as in Example 1. The particles were well fused, but the color unevenness was large and the foamed product was not good.

[0107]

[Comparative Example 10] In this comparative example, a pigment (manufactured by Mitsubishi Kasei Hoechst Co., Ltd., Dinics Green 5G) was used instead of the dye.
SE) was used in the same manner as in Example 1 with 0.05 part.

The expandable particles obtained were colored green and had uneven color. The inside of the mixer was not colored green. When the expandable particles were pre-expanded in the same manner as in Example 1, the color unevenness was large at 13%. Using the expanded particles, a foamed molded product was produced in the same manner as in Example 1. The particles were well fused, but the color unevenness was large and the foamed product was not good.

[0109]

Comparative Example 11 In this comparative example, the same procedure as in Example 1 was carried out using a dye containing carbon black. The dye used was DIARESIN BLACK B manufactured by Mitsubishi Chemical Corporation, and this was added at a ratio of 0.035 parts to 100 parts of the resin.

The expandable particles obtained were colored gray and had no color unevenness, but black carbon black adhered to the inside of the mixer. This expandable particle was used in Example 1.
When pre-expanded in the same manner as above, color unevenness is 0.03.
% Was hardly recognized. Further, when a foamed molded product was produced using the pre-expanded particles in the same manner as in Example 1, the moldability was good, but carbon black adhered to the inside of the molding die.

[0111]

Comparative Example 12 This comparative example is an example in which carbon black was kneaded instead of using a dye to give a gray color. The details are as follows.

First, 100 parts of polyethylene (Yukaron HE60, manufactured by Mitsubishi Chemical Corporation) and 0.0 parts of carbon black were added.
3 parts were mixed and the mixture was fed into an extruder to make carbon-containing polyethylene pellets.

Then, 100 parts of pure water, 3 parts of tricalcium phosphate and 0.02 part of sodium dodecylbenzenesulfonate were put into an autoclave, and the above pellets were added and stirred to suspend the pellets in an aqueous medium.

Separately, 0.3 part of benzoyl peroxide as a polymerization catalyst, 0.01 part of t-butylperoxybenzoate, and 0.25 part of dicumyl peroxide as a crosslinking agent were added to 70 parts of a styrene monomer. Dissolve it to make a monomer solution, add this solution to the above-mentioned aqueous medium to allow the monomer to be absorbed in pellets, and then hold at a temperature of 85 ° C for 4 hours for polymerization, and then raise the temperature to 143 ° C. Then, this temperature was maintained for 3 hours to complete the polymerization, and then the mixture was cooled to obtain particles of a graft polymer.

The graft polymer particles were placed in a pressure-tight rotary mixer and impregnated with a blowing agent in a dry manner. That is,
To 100 parts of the above graft polymer particles, 1.5 parts of toluene was added, and the mixture was hermetically closed and 14 parts of butane was press-fitted into this mixer.
While rotating the mixer at a temperature of 70 ° C. for 3 hours, the mixture was impregnated with a foaming agent to obtain gray-colored expandable particles.
Carbon black adhered to the inner surface of the mixer and was black.

The expandable particles thus obtained were pre-expanded to have a bulk ratio of 55 times, and foamed particles having a dark color unevenness of 0.03% were obtained. The foamed particles were allowed to stand at room temperature for 24 hours, then placed in the same mold as in Example 1 and foamed in the same manner to obtain a foamed molded product. The foam had uneven color, and carbon black adhered to the inside of the mold to make it black.

[0117]

Comparative Example 13 In this comparative example, carbon black was not added to polyethylene, which is the backbone of the graft polymer, but instead carbon black was added to the styrene-based monomer for graft polymerization, and thus foaming was colored in gray. This is the case when the particles are made of conductive particles. The details are as follows.

In the production of the graft polymer of Comparative Example 12, polyethylene particles not containing carbon black were used, 0.03 parts of carbon black was added to 100 parts of styrene monomer, and the time was maintained at 85 ° C. Was carried out in the same manner as in Comparative Example 12 except that the temperature was increased to 7 hours to obtain graft polymer particles. Even so, the graft polymerization was not completed, and the obtained graft polymer contained about 5% by weight of styrene monomer, and the agglomerated particles were about 10%.
There was also%.

Using the graft polymer particles thus obtained, a foaming agent was pressed in the same manner as in Comparative Example 12 to obtain expandable particles. The expandable particles obtained were colored gray. Further, carbon black adhered to the inner surface of the mixer and was black.

When the obtained expandable particles were pre-expanded in the same manner as in Comparative Example 12, 0.03% of expanded particles having dark color unevenness were obtained. Further, the pre-expanded particles were put into a mold and expanded in the same manner as in Comparative Example 12 to obtain an expanded molded article. The molded body had uneven color, and carbon black adhered to the inner surface of the mold to be black.

Claims (4)

[Claims] 1. A styrene resin, an aromatic hydrocarbon,
Expandable colored resin particles comprising an anthraquinone or perinone dye having a solubility of 0.1 g / 100 ml or more in the aromatic hydrocarbon and a foaming agent. 2. A styrene-based resin is placed in a pressure-tight sealed mixer, and an aromatic hydrocarbon and an anthraquinone-based or perinone-based resin having a solubility of 0.1 g / 100 ml or more in the aromatic hydrocarbon are placed in the mixer. A method for producing expandable colored resin particles, which comprises adding a dye, heating while stirring, and press-fitting a foaming agent into this. 3. The styrene resin is an olefin resin 1.
The expandable colored resin particles according to claim 1, which is a graft polymer obtained by graft-polymerizing 0.5 to 5 parts by weight of a styrene-based monomer with respect to parts by weight. 4. A graft polymer obtained by graft-polymerizing 0.5 to 5 parts by weight of a styrene-based monomer with respect to 1 part by weight of an olefin-based resin is used as the styrene-based resin. The method for producing expandable colored resin particles according to claim 2.