JP3527134B2 - Polycarbonate resin composition and molded article - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polycarbonate resin composition, and in particular, it is excellent in mechanical strength, heat resistance, transparency and antistatic property and is used as a component material for electric / electronic equipment such as optical disk cartridges and office equipment. The present invention relates to a polycarbonate resin composition that can be preferably used.

[0002]

2. Description of the Related Art Conventionally, polycarbonate resins have been excellent in impact resistance, heat resistance, transparency, moldability, and dimensional stability, so they have been used for parts of electric / electronic equipment, OA equipment / office equipment, and various machines. Has been. Among these parts, optical disk cartridges, copiers, fax machines, printers, etc. have problems such as repeated loading and unloading and static electricity generated by parts and paper. The solution is attempted by adding an inhibitor.

In order to prevent the static charge of the polycarbonate resin, conductive additives such as carbon black and conductive metal powder, and surfactants are used. However, the addition of these antistatic agents has problems such as impairing transparency and increasing the amount used in the former case. Further, in the latter, although transparency is secured, problems such as low compatibility and heat resistance and coloring yellow due to retention during melt molding have been pointed out. Here, in the case where carbon black is added or when yellowing is intense, transparency is simply lowered, or in addition to becoming opaque, it becomes impossible to adjust to an arbitrary color, particularly a light color, and The field of application will be greatly limited.

As a method for solving these problems, Japanese Patent Publication No. 1
JP-A-29500 discloses an antistatic agent for synthetic polymers containing a phosphonium sulfonate represented by a specific chemical formula as an important component, and is also applied to a polycarbonate resin. In JP-B-7-39537, 0.1 to 20 parts by weight of a phosphonium sulfonate having a specific chemical formula and 0.01 to 1.0 parts by weight of a phosphite are used in combination with 100 parts by weight of a polycarbonate resin. Is disclosed. Further, JP-B-8-6017 discloses that, with respect to 100 parts by weight of a polycarbonate resin, 0.1 to 20 parts by weight of a phosphonium sulfonate of the above-mentioned specific chemical formula and 0.001 to 1 part by weight of a specific boric acid derivative are used. Polycarbonate resin compositions containing are disclosed. further,
JP-A-3-81363 discloses a specific sulfonate compound / fatty acid partial ester of polyhydric alcohol / polystyrene-based polymer compound = 20 to 78/2 to 25/20.
Disclosed is an antistatic agent composition for a polycarbonate resin in the range of -78 (wt%).

That is, among these, in the inventions disclosed in 1 to 3, the polycarbonate resin is used in combination with a specific phosphonium sulfonate salt as an antistatic agent, and a third component is used in combination to prevent thermal deterioration in the melt retention. It is something to prevent. However, in order to prevent this decrease in heat resistance, for example, phosphite ester,
It is necessary to add about 0.1 part by weight to 100 parts by weight of the polycarbonate resin. This amount of addition may cause other problems such as reduction in hot water resistance of the molded product, that is, reduction in hydrolysis resistance of the polycarbonate resin.

[0006]

SUMMARY OF THE INVENTION The present invention provides an antistatic effect by adding a relatively small amount without impairing mechanical strength such as impact resistance and transparency, and heat resistance and hot water resistance. An object is to provide an excellent polycarbonate resin composition.

[0007]

The present inventor diligently studied the heat resistance of an antistatic agent-containing composition used for a polycarbonate resin and the effect of adding a third component. As a result, they have found that these problems can be solved without lowering the hot water resistance when the specific organic siloxane is selectively used in the polycarbonate resin together with the specific antistatic agent, and the present invention has been completed.

That is, the present invention relates to (1) 100 parts by weight of a polycarbonate resin,
A polycarbonate resin composition comprising (A) 0.1 to 20 parts by weight of an anionic antistatic agent and (B) 0.002 to 2 parts by weight of an organic siloxane having a phenyl group, a vinyl group and an alkoxy group. (2) The polycarbonate resin composition according to (1) above, wherein the anionic antistatic agent is a sulfonic acid compound. (3) The polycarbonate resin composition according to the above (2), wherein the sulfonic acid compound is a phosphonium sulfonic acid salt represented by the formula (I).

[0009]

[Chemical 2]

(4) A molded product comprising the polycarbonate resin composition according to any one of (1) to (3) above. (5) The molded product according to (4) above, wherein the molded product is transparent. (6) The present invention provides the molded article according to (4) or (5) above, which is a cartridge for an information recording medium.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The polycarbonate resin used in the present invention is preferably an aromatic polycarbonate resin, and there are no particular limitations, and various types can be used. Generally, an aromatic polycarbonate produced by the reaction of a dihydric phenol and a carbonate precursor can be used. That is, a product produced by reacting a dihydric phenol with a carbonate precursor such as phosgene by a solution method or by reacting a dihydric phenol with a diphenyl carbonate by a transesterification method can be used.

As the dihydric phenol, various ones can be mentioned, but in particular, 2,2-bis (4-hydroxyphenyl) propane [bisphenol A], bis (4-hydroxyphenyl) methane, 1,1-bis ( 4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxy-)
3,5-Dimethylphenyl) propane, 4,4'-dihydroxydiphenyl, bis (4-hydroxyphenyl)
Cycloalkane, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, bis ( 4-hydroxyphenyl) ketone etc. are mentioned. Other dihydric phenols include hydroquinone, resorcin, catechol and the like. These dihydric phenols may be used alone or in combination of two or more.

Particularly preferred divalent phenols are bis (hydroxyphenyl) alkanes, particularly bisphenol A or bisphenol A as a main raw material. Examples of the carbonate precursor include carbonyl halide, carbonyl ester, or haloformate, specifically, phosgene, dihaloformate of dihydric phenol, diphenyl carbonate, dimethyl carbonate, diethyl carbonate and the like.

The polycarbonate resin may have a branched structure, and as the branching agent, 1,1,1-tris (4-hydroxyphenyl) ethane, α, α ′,
α ″ -tris (4-vidroxyphenyl) -1,3,5
-Triisopropylbenzene, phloroglysin, trimellitic acid, isatin bis (o-cresol) and the like.

The polycarbonate resin used in the present invention may be a copolymer having a polycarbonate part and a polyorganosiloxane part, or an aromatic polycarbonate resin containing this copolymer. It may also be a polyester-polycarbonate resin obtained by polymerizing a polycarbonate in the presence of an ester precursor such as a difunctional carboxylic acid such as terephthalic acid or an ester-forming derivative thereof.

The end groups of the polycarbonate resin used in the present invention include a phenyl group, a pt-butylphenyl group, a p-cumylphenyl group, a hydroxy group, etc., and the ratio of the hydroxy groups to all the end groups is. 50%
The following is preferable. The polycarbonate resin used in the present invention has a viscosity average molecular weight (Mv) of preferably 10,000 to 40,000, more preferably 1
2,000 to 35,000, particularly preferably 14,000
It is in the range of 0 to 30,000. Here, when the viscosity average molecular weight (Mv) is less than 10,000, strength,
In particular, the impact resistance becomes insufficient, and if it exceeds 40,000, the melt viscosity may be high and the moldability may be poor.

Next, the compounding ingredient of the present invention, (A)
The anionic antistatic agent is not particularly limited and may be appropriately selected and used from known antistatic agents for polycarbonate resins. Among them, a sulfonic acid compound is preferably used. Here, the sulfonic acid compound is not particularly limited, and examples thereof include the compounds shown below.

R-SO ³ -M ^{+ In the} above, M is a metal ion, phosphonium ion,
It represents an ion selected from ammonium ions. Specific examples of M include alkali metal ions such as sodium ion, potassium ion and lithium ion, alkaline earth metal ions such as calcium ion and lithium ion,
Examples thereof include aene ion, phosphonium ion and ammonium ion. Among these ions, alkali metal ions, ammonium ions, phosphonium ions and the like are preferable. In the case of a divalent metal ion, 1 mol of metal ion corresponds to 2 mol of sulfonic acid group. R is an organic group, and examples thereof include an alkyl group, an aryl group, and an aromatic dicarbonyl group.

However, in consideration of compatibility with polycarbonate resin, heat resistance, etc., the phosphonium sulfonate represented by the following formula (I) is preferably used as the antistatic agent of the component (B) of the present invention.

[0020]

[Chemical 3]

In the formula, R ¹ is an alkyl group or aryl group having 1 to 40 carbon atoms, R ^{2 to} R ⁵ are hydrogen atoms, an alkyl group or aryl group having 1 to 10 carbon atoms, and these are the same. But it can be different. The phosphonium sulfonate salt represented by the formula (I) is composed of an organic sulfonium anion and an organic phosphonium cation. As the organic sulfonate anion, specifically, butyl sulfonate, octyl sulfonate, lauryl sulfonate, aliphatic sulfonates such as dodecyl sulfonate, butylbenzene sulfonate, dodecylbenzene sulfonate, octadecylbenzene sulfonate,
Substituted benzene sulfonates such as dibutyl benzene sulfonate, unsubstituted or substituted naphthyl sulfonates such as naphthyl sulfonate, diisopropyri naphthyl sulfonate, and dibutyl naphthyl sulfonate can be exemplified. Among these, R ¹ is preferably an aryl group in terms of transparency, heat resistance, compatibility with a polycarbonate resin, and the like, and a group derived from an alkylbenzene or an alkylnaphthalene ring is particularly preferable.

Specific examples of the organic phosphonium cation include aliphatic phosphonium such as tetramethylphosphonium, tetraethylphosphonium, tetrabutylphosphonium, tributylethylphosphonium and tributylethylphosphonium, triphenylmethylphosphonium, triethylbenzylphosphonium and tributylbenzyl. Examples thereof include aromatic phosphonium such as phosphonium.

Specific examples of the phosphonium sulfonate salt as the component (A) of the present invention include phosphonium dodecyl sulfonate, phosphonium dodecyl benzene sulfonate, and tetrabutyl phosphonium dodecyl benzene sulfonate. Here, the anionic antistatic agent as the component (A) is 0.1 to 20 parts by weight, preferably 0.3 to 5 parts by weight with respect to 100 parts by weight of the polycarbonate resin.
It is compounded in parts by weight. If the blending amount is less than 0.1 part by weight, a sufficient antistatic effect cannot be obtained, and if it exceeds 20 parts by weight, mechanical strength such as impact resistance is lowered and silver is generated on the surface of the molded product. It may cause deterioration of appearance.

Next, the organosiloxane as the component (B) has a phenyl group, a vinyl group and an alkoxy group. That is, this organosiloxane is one in which two bonds of silicon in the molecule are substituted with a phenyl group at an arbitrary ratio. Further, it has a vinyl group at any silicon position of the siloxane bond, and the silicon at the terminal of the main chain or side chain of the siloxane bond has a carbon number of usually 1 to 5 such as methoxy group, ethoxy group, propoxy group. It has an alkoxy group. When a general organic siloxane having no phenyl group is used, the transparency of the polycarbonate resin composition is lowered due to the compatibility with the polycarbonate resin, the refractive index, and the like. In the present invention, although the reason is not clear, the purpose of the present invention cannot be achieved only by a phenyl group, and the presence of a vinyl group and an alkoxy group is essential, and these are surprising. It was first revealed by the experiments of the present inventor.

The specific organosiloxane as the component (B) is 0.002 with respect to 100 parts by weight of the polycarbonate resin.
˜2 parts by weight, preferably 0.005 to 1 part by weight. Here, if the amount is less than 0.002 parts by weight, the effect of improving residence heat resistance cannot be obtained, and if it exceeds 2 parts by weight, further improvement in residence heat resistance cannot be expected.
The antistatic performance may decrease.

Other additives may be added to the polycarbonate resin composition of the present invention within a range that does not significantly impair the effects of the present invention. For example, antioxidants, various release agents, other antistatic agents and the like. Examples of antioxidants include phosphoric acid ester-based and phenol-based antioxidants. As the phosphorous acid ester in the phosphoric acid ester-based antioxidant,
For example, triphenyl phosphite, tris nonyl phenyl phosphite, tris (2,4-di-tert-
Butylphenyl) phosphite, trinolyl phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tricyclohexyl phosphite, monobutyl diphenyl phosphite, monooctyl diphite. Enylphosphite, bis (2.6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octylphosphite, tetrakis ( 2,4-di-tert-butylphenyl) -4,4-diphenylene phosphonite and other phosphorous acid triesters, diesters, and monoesters. Among them, trisnonylphenyl phosphite, tris (2,4-di-tert-butylphenyl) phosphite, distearyl pentaerythritol diphosphato and the like are preferable.

Examples of the phosphoric acid ester include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, triphenyl phosphate, tricresyl phosphate, tris (nonylphenyl) phosphate, 2-ethylphenyl diphenyl phosphate and the like. Further, as a phenol-based antioxidant, 2,6-di-tert-butyl-
4-methylphenol, tetrakis [methylene-3-
(3 ', 5-di-tert-butyl-4'-hydroxyphenyl) propionate] methane, stearyl-β-
(3,5-Di-tert-butyl-4-hydroxyphenyl) propionate, 3,5-di-tert-butyl-4-hydroxybenzylphosphonate-diester, bis (3,5-di-tert-butyl) Examples include ethyl-4-hydroxybenzylphosphonate) calcium and the like.

Among these antioxidants, the compounding amount of the phosphoric acid ester type antioxidant is usually 0.0001 to 0.05 part by weight, more preferably 0.005 to 0.03 part by weight. . Here, if the blending amount is less than 0.0001 parts by weight, the contribution to the resin stability is small, and if it exceeds 0.05 parts by weight, the hot water resistance, the hydrolysis resistance and the like may decrease. Therefore, the optimum addition amount is selected in consideration of the application of the present invention, the place of use and the like.

The release agent is a fatty acid monoglyceride, for example, a C14-30 fatty acid monoglyceride is a monoester compound of a C14-30 fatty acid and glycerin, such as palmitic acid monoglyceride or stearin. Examples thereof include acid monoglyceride, arachidic acid monoglyceride, behenic acid monoglyceride, montanic acid monoglyceride and the like, and a mixture thereof can also be used. As fatty acid monoglyceride,
From the viewpoint of releasability, stearic acid monoglyceride and behenic acid monoglyceride are preferable, and stearic acid monoglyceride is particularly preferable. The content of the fatty acid monoglyceride is usually 0.005 to 1.0 part by weight, preferably 0.01 to 0.5 part by weight.

As other compounding ingredients, the molecular weight is from 500 to
1,000,000 polyalkylene glycol, thermoplastic resins and other polystyrene resins that contribute to the improvement of antistatic properties of polycarbonate resins such as polyamide resins,
There are thermoplastic resins such as rubber-modified polystyrene resin, polyester resin, and polyolefin resin, and thermoplastic elastomers such as styrene-butadiene rubber, ethylene-propylene rubber, polyamide elastomer, and acrylic elastomer as impact modifiers.

Examples of the filler include glass fiber, carbon fiber, metal fiber, carbon black, talc, zeolite, calcium carbonate, silica, mica, titanium oxide and the like. Further, additives such as flame retardants, colorants (pigments, dyes), benzotriazole-based UV absorbers, benzophenone-based UV absorbers, salicylate-based UV absorbers, various light stabilizers, and plasticizers can be blended as necessary.

The polycarbonate resin composition of the present invention is
Ingredients (A) and (B), as well as other necessary components, are added to the polycarbonate resin by various mixing means, usually melt kneading means, and pelletized by an extrusion kneading molding machine. It is also possible to prepare a masterbatch pellet containing a compounding component at a high concentration, which is composed of a resin such as a polycarbonate resin and a compounding component, mix this with a polycarbonate resin, and perform melt molding.

The polycarbonate resin composition of the present invention is
Various molding methods such as injection molding, injection compression molding, extrusion molding, blow molding, compression molding and the like can be used to obtain molded articles such as molded articles, hollow molded articles, films and sheets. Among them, injection molding and injection compression molding can be preferably adopted. The molding temperature in this case can be appropriately selected depending on the molecular weight of the polycarbonate resin used, but is usually 230 to 34.
It is in the range of 0 ° C. The molded article of the present invention can be used particularly in the transparent field where antistatic properties are required. Therefore, excellent antistatic property, strength, heat resistance,
In addition to retention heat resistance, hot water resistance, and hydrolysis resistance, the characteristics of light-colored and light-colored molded products, etc.
It is used for electronic / electrical devices such as office automation equipment, office equipment, home appliances, mechanical parts, and automobile parts. In particular, it is suitably used for an optical disk cartridge, a copying machine, a paper feeding unit of a printing machine, a paper discharging unit such as a tray.

[0034]

EXAMPLES Hereinafter, the present invention will be described with reference to Examples and Comparative Examples.
Although described in detail, the present invention is not limited to these examples. The blending amount is shown in parts by weight. In addition, the method of measuring physical properties evaluated is shown below.

(1) Surface specific resistance: According to JIS K6911. (2) Yellow index: According to JIS K7105. (3) Total light transmittance ... According to JIS K7105. (4) Tensile strength: According to JIS K7113. (5) Tensile elongation: According to JIS K7113. (6) Izod impact strength: Notched according to JIS K7110.

Examples 1 to 8 and Comparative Examples 1 to 5 As shown in Tables 1 and 2, 100 parts by weight of PC [aromatic polycarbonate resin: viscosity average molecular weight = 22,000] was used as follows. Predetermined amounts (parts by weight) of (A) antistatic agent, (B) organosiloxane, (C) antioxidant, and (D) release agent are mixed and the resin temperature is 280 ° C. in an extruder.
Melt-kneading and extrusion molding were carried out to obtain a polycarbonate resin composition pellet. After drying the pellets at 120 ° C. for 6 hours, an injection molding machine [manufactured by Toshiba Machine Co., Ltd .: Toshiba ISI50]
Mold], a test piece was injection-molded at a resin temperature of 300 ° C. and a molding cycle of 5 minutes. The first test piece for molding was set as no retention, and the test piece for the fourth shot was set as 20 minutes for retention, and each test piece was measured and evaluated. The evaluation results are shown in Table 1 and Table 2.
Shown in the table. The physical properties were measured 24 hours after molding (23
(° C, humidity 60%).

Component (A): Antistatic agent Tetrabutylphosphonium salt of dodecylbenzenesulfonic acid [Takemoto Yushi Co., Ltd .: Antistatic agent IPS101] Dodecylbenzenesulfonic acid sodium salt [Takemoto Yushi Co., Ltd .: Elecut S412] Component (B) ): Organic siloxane Organic siloxane having phenyl group, vinyl group and methoxy group [Shin-Etsu Chemical Co., Ltd .: KR219] Organic siloxane having only phenyl group [Shin-Etsu Chemical Co., Ltd .: KF56] Organic siloxane having only methoxy group [ Shin-Etsu Chemical Co., Ltd .: KR851]

Component (C): antioxidant tris (2,4-di-t-butylphenyl) phosphite [Ciba Specialty Chemicals: Irgafos 168] triphenylphosphine [Johoku Chemical Co., Ltd.] component ( D): Release agent pentaerythritol tetrastearate

[0039]

[Table 1]

[0040]

[Table 2]

[0041]

INDUSTRIAL APPLICABILITY The polycarbonate resin composition of the present invention is excellent in antistatic properties and mechanical properties, and has retention heat resistance, that is, there is no deterioration in various physical properties even after retention, and particularly transparency and yellowing resistance. Excellent in denaturation, hydrolysis resistance,
It has excellent hot water resistance, and transparent molded parts and light / light colored colored molded products can be easily obtained. Due to these excellent effects, it can be broadly applied to fields where it has been difficult to use conventionally.

Claims (6)

(57) [Claims] 1. To 100 parts by weight of a polycarbonate resin, 0.002 to 0.12 parts by weight of an anionic antistatic agent (A) and 0.002 to (B) an organosiloxane having a phenyl group, a vinyl group and an alkoxy group A polycarbonate resin composition containing 2 parts by weight. 2. The polycarbonate resin composition according to claim 1, wherein the anionic antistatic agent is a sulfonic acid compound. 3. The polycarbonate resin composition according to claim 2, wherein the sulfonic acid compound is a phosphonium sulfonate of the formula (I). [Chemical 1] (In the formula, R ¹ is an alkyl group having 1 to 40 carbon atoms or ari.
R ^{2 to} R ⁵ are hydrogen atoms and have 1 to 10 carbon atoms.
Is an alkyl group or an aryl group of
May also be different. ) 4. A molded product comprising the polycarbonate resin composition according to claim 1. 5. The molded product according to claim 4, wherein the molded product is transparent. 6. The molded product according to claim 4, which is a recording medium cartridge.