JP3444383B2 - Antistatic masterbatch color for thermoplastic resin and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a coloring agent for a thermoplastic resin containing an antistatic agent. More specifically, it relates to a coloring agent containing an antistatic agent in a high concentration and having both antistatic and coloring functions, and a method for producing the same.

The masterbatch color of the present invention can be used in any molding method such as injection, extrusion and hollow molding.

[0003]

2. Description of the Related Art Conventionally, an antistatic treatment for a thermoplastic resin molded product has been carried out by kneading or applying an antistatic agent into a thermoplastic resin at a concentration suitable for its application, or kneading a conductive filler into the resin. It has been achieved without any difficulty. The antistatic agent is a surfactant or a conductive polymer, and the type and amount to be used are selected depending on the glass transition temperature of the resin, molding method, molding temperature, application, etc. The compound is kneaded to the required concentration or the master batch is kneaded to a concentrated concentration.

On the other hand, coloring of a thermoplastic resin molded article is performed by pigments or dyes or both (collectively referred to as dyes and pigments).
It is achieved by adding a necessary amount to a thermoplastic resin by finely dispersing and formulating. Coloring of resin is a masterbatch in which dyes and pigments are kneaded into the resin prior to the molding process and used as a color compound for molding, or dyes and pigments with a concentration higher than that required for the molded product are finely dispersed with a dispersant etc. It is performed by adding a colorant such as a color or a dry color to the molding resin at the time of molding.

Under these circumstances, from the viewpoints of handling, non-scattering property, addition cost and the like, which are required in recent years in the field of resin molding, from the viewpoints of handling property, non-scattering property, addition cost, etc., master in antistatic treatment and coloring. Batches are becoming more popular. From the viewpoints of cost reduction, general-purpose use, etc., a masterbatch having higher concentration or a combination of both functions is being studied so as to further reduce the use and addition rate.

[0006]

When both the functions of antistatic and coloring are combined, the total amount of both functional components in the masterbatch inevitably increases, but from the viewpoint of production and shape retention, etc. There is an addition rate limit (concentration increase limit) of each component in the masterbatch. Dyes and pigments have a wide range in which the resin can maintain the function of a masterbatch carrier and can be made relatively high in concentration, but it is difficult to increase the concentration of the antistatic agent when the antistatic agent is a surfactant. . Surfactants have poor compatibility with resins in many cases and have a lower melting point than resins in the first place, and the viscosity after melting is too different from the resin, so it is necessary to melt knead with the resin for a long time in batch kneading. It has the disadvantage of causing deterioration of the kneaded product, and in continuous kneading, discharge defects occur due to blocking of the mixture or slipping in the kneader at the raw material mixing stage,
The raw material supply method and the kneading machine had to be improved, which led to deterioration of the kneaded product as in the case of batch kneading.

Particularly, the surfactants which are often used nowadays have a melting point in the range of room temperature or lower to around 100 ° C. and are generally lower than the melting temperature of the thermoplastic resin, so that such a problem occurs. In the continuous kneading with the coloring component, unevenness of the concentration of the component in the discharged product was caused.

Further, the concentration of the coloring component is optionally changed according to the hue required of the molded product, and the addition ratio of 2% or less to the molding resin can be sufficiently designed, but the antistatic agent has a surface resistance value of the resin at a specific level. There is always the required amount to control
It was difficult to increase the concentration of the antistatic agent in accordance with the low addition rate of the colorant to the molding resin, and to cope with the low addition rate.

Therefore, various proposals have been made for increasing the concentration of the conventional antistatic surfactant, but each has its drawbacks. For example, as shown in JP-A-57-30746, melt kneading with a resin having good fluidity, or as shown in JP-A-62-109854, melt mixing with a resin is performed by a batch type kneader. Although a method has been proposed, the former is considered to reduce the strength of the added resin molded product, and the latter is considered to decrease the productivity.

Further, as disclosed in JP-A-6-322140, fine particles (diameter of 5 to 50 nm) are used for the purpose of enabling continuous kneading and eliminating blocking of kneaded materials.
It has also been proposed to utilize the viscosity-creating effect of inorganic oxides. However, in order to bring out the effect, it must be mixed with a surfactant in advance, and in the case of a liquid surfactant, it is necessary to devise a method for supplying the mixture to the kneader, and in the case of a solid surfactant, heating is required. It is necessary to mix the liquefied materials and then mix them.

[0011]

Under the circumstances, the present inventors have earnestly studied a colorant containing a high concentration of an antistatic agent, and as a result, a thermoplastic resin and a coloring component such as a pigment or a dye have been obtained. When melt-kneading and the antistatic agent, if the diatomaceous earth is added in a specific ratio to the antistatic agent, the melt-kneading becomes easy,
It has been found that it is possible to increase the concentration of the antistatic agent.

That is, according to the present invention, a thermoplastic resin is used as a carrier resin, and an antistatic master bar for a thermoplastic resin is prepared by kneading an antistatic agent, diatomaceous earth, a pigment and / or a dye.
It is a touch color . The present invention also relates to an antistatic master bag for a thermoplastic resin, which comprises kneading a thermoplastic resin carrier with an antistatic agent, diatomaceous earth and a pigment and / or dye.
It is a production method of Tikara .

The present invention will be described in detail below. The present invention, when a coloring component and an antistatic surfactant are mixed in a high concentration in a large amount in a thermoplastic resin, a large lump of the mixture is generated in the mixing stage and the kneading property is caused by a slip in a kneading machine. It is characterized by improved anti-slip performance due to the unique porosity of the added diatomaceous earth, and oil absorption performance. In particular, diatomaceous earth can be easily mixed with other components, and can be stably extruded without sticking to the hopper or formation of agglomerate at the extruder feed port during extrusion kneading, and there is no blocking of the obtained masterbatch.

According to the present invention, a masterbatch obtained by combining a thermoplastic resin, an antistatic agent, and diatomaceous earth and excluding dyes and pigments can be easily recalled. However, the required amount of antistatic property for a thermoplastic resin molded article is prevented. With the addition of agents, undesired coloring due to the addition of diatomaceous earth is unavoidable. In that respect, the combined use of dyes and pigments is important in minimizing the effect of this undesired coloring.

The thermoplastic resin used as the carrier resin in the present invention includes polyethylene, polypropylene and ethylene-α.
Olefin copolymer, propylene-α olefin copolymer, olefin resin such as thermoplastic olefin, polystyrene, styrene resin such as styrene acrylonitrile copolymer, styrene acrylonitrile butadiene copolymer, acrylic ester such as methyl methacrylate resins, nylon 6, nylon 66, nylon 12, polycarbonate, polyethylene terephthalate, a resin such as polybutylene terephthalate powder,
The shape thereof such as granular shape does not matter.

In the present invention, these resins may have an acid group such as α, β-unsaturated carboxylic acid or an anhydride thereof by post-treatment after synthesis. The pigments used in the present invention are known in the field of plastics processing, for example, titanium oxide, zinc oxide, rouge, titanium oxide calcined pigments, ultramarine blue, cobalt aluminate, inorganic pigments such as carbon black and azo pigments, quinacridone. And organic pigments such as anthraquinone, perylene, isoindolinone, phthalocyanine, quinophthalone, slene, diketopyrrolopyrrole, and extender pigments such as barium sulfate, calcium carbonate, and talc.

The dyes used in the present invention are known in the field of plastics processing, for example, azo type, perylene type,
Examples thereof include phthalocyanine-based and anthraquinone-based acidic, basic, vat dyes, and oil-soluble dyes.

The antistatic agent used in the present invention is a surfactant having an antistatic property, and such a surfactant is known as an antistatic agent in the field of plastic processing and has a melting point of 80 ° C. or lower. And an antistatic agent having When the temperature is 80 ° C or lower, problems such as hardening of the mixture during mixing and instability of extrusion are likely to occur in the prior art, whereas according to the present invention, this kind of problem does not occur even at 80 ° C or lower. The effect of the invention is remarkably obtained.

Therefore, glycerin fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, alkyldiethanolamine, hydroxyalkylmonoethanolamine, polyoxyethylenealkylamine, polyoxyethylenealkylamine fatty acid ester, alkyldiethanolamide, etc. Ionic surfactant, alkyl sulfonate,
Examples include anionic surfactants such as alkylbenzene sulfonate and alkyl phosphate, cationic surfactants such as tetraalkylammonium salt and trialkylbenzylammonium salt, and amphoteric surfactants such as alkylbetaine and alkylimidazolium betaine. You can

The diatomaceous earth used in the present invention is formed by depositing diatom shells, and is obtained naturally or has an average particle size of 1 to 120 μm and is obtained by firing it. Such diatomaceous earth is a porous substance having small pores in each particle, and is usually mainly used as a filter aid or a filler.

Moreover, such diatomaceous earth used in the present invention is
Made of silicon oxide and other inorganic oxides
Since the pores of about μm penetrate, the oil absorption is high and the bulk is low even if the particle size is relatively large, so it is easy to handle and easy to mix with a resin or an antistatic agent. The diatomaceous earth in the present invention preferably has an oil absorption of more than 120 ml / 100 gr.

In that respect, synthetic silicon oxide is a primary particle of 0.1 μm or less, and since it absorbs oil in the gaps of its agglomerates, it has a high oil absorption but is bulky, so it is difficult to mix it with a resin or an antistatic agent. is there.

The masterbatch color of the present invention may be prepared by mixing the respective components at once with a high speed mixer or a tumbler. Even if the surfactant is liquid, if the amount of diatomaceous earth is properly selected, the powder fluidity of the mixture is obtained. The extrusion kneading does not significantly impair the extrudability. In the present invention, the ratio of the surfactant to the diatomaceous earth is appropriately in the range of 3: 1 to 1: 3, and the total ratio of both is set to 12 to 80% by weight, so that the surfactant is about 9 to 60% by weight. Can be produced by melt-kneading with a single-screw or twin-screw extruder, a Banbury mixer, a kneader, a high-speed rotating intensive mixer, or the like. The shape of the kneaded material is formed by hot-cutting into granules or by cold-cutting sheets or strands into granules depending on how the kneaded product is taken out from the kneader.

Further, the pigment can be used after being easily dispersed in advance by a commonly used method such as a low molecular weight resin or a resin, a heating kneader, a heating roll, a Banbury mixer or a high speed intensive mixer. Similarly, a dispersant such as a metallic soap may be added to the pigment to easily disperse it in advance before use.

Further, a heat stabilizer, a light stabilizer, a flame retardant, a plasticizer, a lubricant or a filler for improving suitability for use can be added as required.

[0026]

EXAMPLES The present invention will now be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples and has a wide range of applications. All parts and percentages in the examples and comparative examples are based on weight.

Examples 1 to 3 and Comparative Examples 1 and 2 60 rutile type titanium oxide having a primary particle size of 0.3 μm
Part, and a mixture containing 40 parts of low-density polyethylene (MFR = 7) was kneaded with a high-speed intensive mixer at 150 ° C. to obtain granular pellets A. Also, 50 parts of β-type copper phthalocyanine blue, low molecular weight polyethylene (MW = 600
The mixture containing 50 parts of 0) was kneaded with a pressure kneader and a heating three-roll and crushed with a crusher (<7 mm length) to obtain a product B. All of these and low-density polyethylene C or high-density polyethylene D shown in Table 1 and surfactants diethanolamine E and diatomaceous earth F as antistatic agents at the compounding ratio (parts) shown in Table 1, respectively, and the capacity of the high-speed mixer of 7
The mixture was put so that it was split and mixed for 3 minutes. Then, the mixture was kneaded with a twin-screw extruder (30 mmφ) under heating at 170 ° C.,
The extruded melt was cooled with water, and then processed into a master batch color pellet having a diameter and a length of 3 to 5 mm by a pelletizer. The obtained masterbatch color was added to the high-density polyethylene D shown in Table 1 at the addition rate shown in the same table, and melt-kneaded at 170 ° C. in a small blow molding machine (40 mmφ) to form a rectangular parallelepiped bottle. . The bottle is under constant temperature and humidity conditions (25
After storage for 3 days at 40 ℃, the thickness is 1mm from the bottle.
A thick plate was cut out and the surface resistance value was measured according to JIS K6911.

The results are shown in Table 1. The masterbatch color containing the diatomaceous earth of the present invention can be kneaded with an antistatic agent at a high concentration without blocking and is beautiful when molded into a blow bottle. Surface resistance value of 10 without dust adhesion
The value at ¹⁰ Ω level is shown.

In the comparative example, since the masterbatch color could not be prepared, the test piece could not be prepared and therefore the surface resistance value could not be measured. The same applies to Tables 2 and 3 described later.

[0030]

[Table 1]

Details of the blended raw materials in Table 1 are as follows. Resin C: Low density polyethylene MFR (190 ° C load 2.16K
g) = 8 Density = 0.924 Resin D: High density polyethylene MFR (190 ° C load 2.16K
g) = 0.8 Density = 0.955 Antistatic agent E: N, N-bis (2-hydroxyethyl)
Fatty acid amine mp = 13 ° C. Diatomaceous earth F: Average particle size = 10 μm Oil absorption = 125 ml / 100
gr

The criteria for evaluation of the masterbatch color in Table 1 are as follows. In the case of mixed state 3: The mixture has no solidity and has fluidity. 2: A part of the mixture is solidified. It hardens easily and hardens when pressed. 1: The mixture solidifies.

In the case of extrusion condition 3: Supply and extrusion are stable. 2: Extrusion in which the supply amount was limited due to occasional defective supply of the mixture and uneven discharge of the extrusion. 1: Frequent slipping or blocking of the mixture occurs in the feed zone. Alternatively, only the liquid antistatic agent is extruded and cannot be stably extruded.

Examples 4 to 6 and Comparative Examples 3 to 5 The pigment was used as a furnace carbon black by the method described in Examples 1 to 3 and Comparative Examples 1 and 2 using a pressure kneader, heating three rolls and a crusher. (Primary particle size 24mμ, oil absorption =
Kneaded materials G and H were prepared by using 30 parts of 46 DBPml / 100 gr, PH = 8) or 70 parts of iron oxide, and 70 parts and 30 parts of low molecular weight polyethylene (MW = 6000), respectively. These and low-density polyethylene C or polypropylene I and diethanolamine E or fatty acid monoglyceride J and / or diatomaceous earth K shown in Table 2 were all added at the compounding ratio (part) shown in Table 2 to make up 70% of the capacity of the high-speed mixer. Mix for minutes. After that, the mixture containing polyethylene C was kneaded with a twin-screw extruder (30 mmφ) under heating at 170 ° C., and in the case of polypropylene I, was kneaded under heating at 190 ° C., and the extruded melt was water-cooled, It was processed into a master batch color pellet having a diameter and a length of 3 to 5 mm with a pelletizer. The obtained pellets were added to polypropylene I shown in Table 2 at the addition rate shown in the same table, and melt-kneaded at 230 ° C. in a small injection molding machine (mold clamping 60 t) to form a flat plate having a thickness of 2.5 mm. did. The flat plate was stored under constant temperature and humidity conditions (25 ° C x 40%) for 3 days and then JISK6
The surface resistance value was measured according to 911.

The results are shown in Table 2. The masterbatch color containing the diatomaceous earth of the present invention can knead the antistatic agent at a high concentration without blocking, and the molded flat plate is beautiful and dust adhesion occurs. There was no surface resistance value of 10 ¹⁰ Ω level.

[0036]

[Table 2]

Details of the blended raw materials in Table 2 are as follows. Resin C: Low-density polyethylene Same as those listed in Table 1 Resin I: Block copolymer polypropylene MFR (230 ° C load 2.16Kg) = 50gr / 10min Antistatic agent E: N, N-bis (2-hydroxyethyl)
Fatty acid amine Same as the product listed in Table 1 Antistatic agent J: fatty acid monoglyceride (main component of glyceride stearate) mp = 66 ° C. diatomaceous earth K: average particle size = 13 μm oil absorption = 210 ml / 100
gr Masterbatch colorization criteria in Table 2 are the same as those in Table 1.

Examples 7 and 8 and Comparative Examples 6 and 7 Rutile type titanium oxide having a primary particle diameter of 0.3 μm, isoindolinone yellow and zinc stearate were used as polypropylene I or polystyrene L as shown in Table 3 and sodium alkyl sulfonate. Table 3 shows M and / or diatomaceous earth F, respectively.
All were mixed in the stated mixing ratio (parts) so as to be 70% of the capacity of the high-speed mixer and mixed for 3 minutes. After that, the mixture was kneaded with a twin-screw extruder (30 mmφ) under heating at 190 ° C.,
After the extruded melt is cooled with water, a master batch color pellet 10 having a diameter and a length of 3 to 5 mm is formed with a pelletizer.
Processed to 0 parts by weight. The obtained pellets were added to polypropylene I shown in Table 3 at the addition rate shown in the same table in the case of a master batch color containing polypropylene, and similarly to polystyrene L in the case of polystyrene, using a small injection molding machine (mold clamping 60 t ) Was melt-kneaded at 230 ° C. to form a flat plate having a thickness of 2.5 mm. The flat plate was stored under constant temperature and humidity conditions (25 ° C x 40%) for 3 days and then JISK6
The surface resistance value was measured according to 911.

The results are shown in Table 2. The masterbatch color containing the diatomaceous earth of the present invention can knead the antistatic agent at a high concentration without blocking, and the molded flat plate is beautiful and dust adhesion occurs. There was no surface resistance value of 10 ¹⁰ Ω level.

[0040]

[Table 3]

Details of the blended raw materials in Table 3 are as follows. Resin I: Block copolymer polypropylene Same as listed in Table 2 Resin L: High impact polystyrene MFR (200 ° C
Load 5kg) = 11gr / 10min Antistatic agent M: Sodium alkyl sulfonate (alkyl:
C _{10 to} C ₁₂ ) mp = 130 ° C. Diatomaceous earth F: same as the product described in Table 1 The criteria for evaluation of masterbatch colorization in Table 3 are the same as those described in Table 1.

[0042]

EFFECTS OF THE INVENTION By using an antistatic agent, diatomaceous earth, a pigment and a dye as components, an antistatic masterbatch color in which a high concentration of an antistatic agent is kneaded into a thermoplastic resin can be produced. It can be used for plastic molding in a small amount as a coloring agent without considering handling separately. This makes it possible to reduce coloring costs.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields investigated (Int.Cl. ⁷ , DB name) C08J 3/22 C08L 1/00-101/16

Claims (6)

(57) [Claims] 1. An antistatic masterbatch color for a thermoplastic resin, which comprises a thermoplastic resin as a carrier resin and is kneaded with an antistatic agent, diatomaceous earth and a pigment and / or dye. 2. The ratio of antistatic agent to diatomaceous earth is from 3: 1.
1: 3, total proportion of both is 12 to 80 parts by weight%
The masterbatch color according to claim 1 . Wherein the antistatic agent is a surfactant according to claim 1
Or the masterbatch color described in 2. 4. A range of diatomaceous earth is the particle size 1~120μm
Located enclosed and masterbatch according to claim 1, wherein the oil absorption amount is in excess of 120 ml / 100 gr
Color . 5. A method for producing an antistatic masterbatch color for a thermoplastic resin, which comprises adding an antistatic agent, diatomaceous earth and a pigment and / or dye to a thermoplastic resin carrier and kneading the mixture. 6. The antistatic agent is a surfactant having antistatic properties, diatomaceous earth the particle size is 1~120μm range
The method for producing a masterbatch color according to claim 5 , wherein the oil absorption amount is in the range and the oil absorption amount exceeds 120 ml / 100 gr.