JP7597553B2 - Polycarbonate resin composition and molded article thereof - Google Patents

Description

The present invention relates to a resin composition containing a specific polycarbonate resin and a specific antistatic agent.

Conventionally, methacrylic resins and polycarbonate resins (hereinafter sometimes referred to as PC) are known as transparent resins, and they are used in a wide range of fields such as electrical and electronic components, optical components, automotive components, and mechanical components in the form of molded products, films, and sheets.

Methacrylic acid resins such as polymethyl methacrylate (hereinafter sometimes referred to as PMMA) have high transparency and high surface hardness (pencil hardness H to 3H), and are widely used as optical materials such as lenses and optical fibers. However, their glass transition temperature is low at around 100°C, and their heat resistance is poor, limiting their use in fields requiring heat resistance. Another problem is that they have low impact resistance.

Polycarbonate resin made from bisphenol A is widely used in vehicles and building materials due to its excellent heat resistance, impact resistance, flame retardancy and transparency. Among these applications, high weather resistance is required, especially for outdoor use, but the weather resistance of polycarbonate resin is generally not as good as other transparent materials such as acrylic resin, and yellowing and devitrification occur when exposed to the outdoors. In addition, the surface is very soft (pencil hardness 4B to 2B) and is easily scratched.

Polycarbonate resins using biomass resources as raw materials and highly heat-resistant amorphous polycarbonate resins made from raw materials obtained from ether diol residues that can be produced from carbohydrates are being studied. In particular, polycarbonate resins using isosorbide as a monomer are characterized by excellent transparency, heat resistance, weather resistance, and surface hardness, and studies are being conducted to take advantage of these characteristics (Patent Documents 1 and 2).

These polycarbonate and acrylic resins are prone to become charged, and there is a problem in that static electricity easily causes dust to adhere to the surface of the molded product. One method of preventing static electricity is known to incorporate hydrophilic polyamide-based polymers such as polyetheresteramide and polyetheramide to impart antistatic properties (Patent Document 3). However, when these hydrophilic polyamide-based polymers are incorporated into polycarbonate or acrylic resins, there is a problem in that transparency is significantly reduced.

Therefore, no polycarbonate resin composition that has good transparency, surface hardness, impact resistance, and antistatic properties has been reported to date.

JP 2009-74031 A JP 2009-102537 A JP 2002-129026 A

An object of the present invention is to provide a polycarbonate resin composition containing a polycarbonate resin having excellent properties such as transparency, surface hardness, impact resistance and antistatic property, and an antistatic agent.

Means for Solving the Problems The present inventors, through extensive research, have discovered that a polycarbonate resin composition having excellent properties such as transparency, surface hardness, impact resistance and antistatic properties can be obtained by containing a polycarbonate resin obtained by polymerizing a diol compound containing isosorbide and a block polymer having a specific structure, and have thus completed the present invention.
That is, according to the present invention, the object of the invention is achieved as follows.

1. A polycarbonate resin composition containing 100 parts by weight of a polycarbonate resin containing 40 mol % or more of structural units (A) represented by the following formula (A) out of 100 mol % of all structural units, and 1 to 20 parts by weight of a block polymer (C) having a structure in which polyolefin blocks and polyether blocks are repeatedly and alternately bonded.

2. The polycarbonate resin composition according to the preceding paragraph 1, wherein the polycarbonate resin further contains a structural unit (B) represented by the following formula (B), and the sum of the structural units (A) and (B) is 80 mol % or more out of 100 mol % of all structural units.

(W represents at least one group selected from the group consisting of an alkylene group having 2 to 30 carbon atoms, a cycloalkylene group having 6 to 30 carbon atoms, and an alkylene group containing a heterocycle having 6 to 30 carbon atoms.)

3. The polycarbonate resin composition according to item 1 or 2 above, wherein a haze of a test piece having a thickness of 3.2 mm is 40 or less.
4. The polycarbonate resin composition according to any one of items 1 to 3 above, which has a Charpy notched impact strength measured in accordance with ISO 179 of 8 kJ/m2 ^{or more} .
5. The polycarbonate resin composition according to any one of items 1 to 4 above, which has a pencil hardness of B or more as measured in accordance with JIS K-5600.
6. The polycarbonate resin composition according to any one of items 1 to 5 above, wherein the surface resistivity of a molded article is 1×10 ¹⁵ (Ω/□) or less.
7. A molded article obtained by molding the polycarbonate resin composition according to any one of items 1 to 6 above.
8. A film or sheet formed from the polycarbonate resin composition according to any one of items 1 to 6 above.

The present invention contains a polycarbonate resin obtained by polymerizing a diol compound containing isosorbide and a block polymer having a specific structure, making it possible to provide a polycarbonate resin composition having excellent properties such as transparency, surface hardness, impact resistance, and antistatic properties. Therefore, the industrial effects achieved by this composition are exceptional.

The present invention is described in detail below.

<Polycarbonate resin>
The polycarbonate resin used in the present invention contains a structural unit (A) represented by the following formula (A): The structural unit (A) is 40 mol% or more, preferably 50 mol% or more, more preferably 60 mol% or more, and particularly preferably 70 mol% or more, based on 100 mol% of all structural units.

(Structural Unit (A))
The structural unit (A) in the present invention is, as shown in the above formula (A), derived from an aliphatic diol having an ether group.
Among the biomass resources constituting the formula (A), the diol having an ether bond is a material having high heat resistance and pencil hardness.
The above formula (A) is exemplified by structural units (A1), (A2) and (A3) represented by the following formulae, which are stereoisomeric.

These are ether diols derived from carbohydrates, and can also be obtained from biomass in nature, making them one of the so-called renewable resources. The structural units (A1), (A2) and (A3) are called isosorbide, isomannide and isoidide, respectively. Isosorbide is obtained by hydrogenating D-glucose obtained from starch, followed by dehydration. Other ether diols can also be obtained by similar reactions, except for the starting material.

Among isosorbide, isomannide, and isoidide, the structural unit derived from isosorbide (1,4;3,6-dianhydro-D-sorbitol) is particularly preferred due to its ease of production and excellent heat resistance.

(Unit (B))
A preferred embodiment of the polycarbonate resin in the present invention is a copolymerized polycarbonate resin that contains the above-mentioned structural unit (A) and a structural unit (B) represented by the following formula (B), in which the total of the structural units (A) and (B) is preferably 80 mol % or more, and more preferably 90 mol % or more, of 100 mol % of all structural units.

(In the formula, W represents at least one group selected from the group consisting of an alkylene group having 2 to 30 carbon atoms, a cycloalkylene group having 6 to 30 carbon atoms, and a heterocycle-containing alkylene group having 6 to 30 carbon atoms.)
The unit (B) is a carbonate unit derived from at least one compound selected from the group consisting of an aliphatic diol compound, an alicyclic diol compound, and a heterocycle-containing diol compound.

Specific examples of the aliphatic diol having 2 to 30 carbon atoms include 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 2-ethyl-1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol, 1,10-decanediol, 1,12-dodecanediol, hydrogenated dilinoleyl glycol, hydrogenated dioleyl glycol, etc. Among them, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-
Dodecanediol is preferred, and 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol are particularly preferred.

Specific examples of alicyclic diol compounds having 6 to 30 carbon atoms include cyclohexanediols such as 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, and 2-methyl-1,4-cyclohexanediol; cyclohexanedimethanols such as 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, and 1,4-cyclohexanedimethanol; norbornane dimethanols such as 2,3-norbornane dimethanol and 2,5-norbornane dimethanol; tricyclodecane dimethanol, pentacyclopentadecanedimethanol, 1,3-adamantanediol, 2,2-adamantanediol, decalin dimethanol, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. Of these, 1,4-cyclohexanedimethanol and tricyclodecane dimethanol are preferred.

Specific examples of heterocycle-containing diol compounds having 6 to 30 carbon atoms include 3,9-bis(2-hydroxyethyl)-2,4,8,10-tetraoxaspiro(5.5)undecane, 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5.5)undecane, 3,9-bis(2-hydroxy-1,1-diethylethyl)-2,4,8,10-tetraoxaspiro(5.5)undecane, and 3,9-bis(2-hydroxy-1,1-dipropylethyl)-2,4,8,10-tetraoxaspiro(5.5)undecane. Preferably, 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5.5)undecane is used.

Two or more of these may be used in combination. In particular, W is preferably an alkylene group having 8 to 12 carbon atoms.

The molar ratio (A/B) of structural unit (A) to structural unit (B) is preferably in the range of 60/40 to 95/5, more preferably in the range of 70/30 to 93/7, and even more preferably in the range of 80/20 to 90/10. Being within the above range is preferable because it provides an excellent balance between surface hardness and impact resistance. The molar ratio (A/B) can be measured and calculated using a proton NMR of JNM-AL400 manufactured by JEOL Ltd.

The diol compound from which the other structural units other than the structural unit (A) and the structural unit (B) are derived may be any of other aliphatic diol compounds, other alicyclic diol compounds, and aromatic dihydroxy compounds. Specific examples include the diol compounds described in WO 2004/111106 and WO 2011/021720, and oxyalkylene glycols such as diethylene glycol, triethylene glycol, tetraethylene glycol, and polyethylene glycol.

Examples of aromatic dihydroxy compounds include α,α'-bis(4-hydroxyphenyl)-m-diisopropylbenzene (bisphenol M), 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide, bisphenol A, 2,2-bis(4-hydroxy-3-methylphenyl)propane (bisphenol C), 2,2-bis(4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane (bisphenol AF), and 1,1-bis(4-hydroxyphenyl)decane.

<Production method of polycarbonate resin>
In the present invention, a diol compound containing a compound of the following formula (a) is used as a raw material for the polycarbonate resin. The compound of the following formula (a) accounts for 40 mol % or more of the total diol components, preferably 50 mol % or more, more preferably 60 mol % or more, and particularly preferably 70 mol % or more.

Furthermore, at least one compound selected from the group consisting of an aliphatic diol compound, an alicyclic diol compound, and a heterocycle-containing diol compound that derives the structural unit (B) represented by the above formula (2) can be used in combination. When used in combination, the total of the diol compound of the above formula (a) and the diol compound that derives the structural unit (B) represented by the above formula (2) is preferably 80 mol % or more, more preferably 90 mol % or more of the total diol components.

The unit (B) is a carbonate unit derived from at least one compound selected from the group consisting of an aliphatic diol compound, an alicyclic diol compound, and a heterocycle-containing diol compound.

In the present invention, a diol compound containing the compound of formula (a) above can be reacted with a carbonate diester in the presence of an ester exchange catalyst to produce a polycarbonate resin.

The polycarbonate resin of the present invention is produced by a method known per se for producing ordinary polycarbonate resins, that is, a method of reacting a diol component with a carbonic acid diester. The basic means for these production methods will be briefly described below.

The transesterification reaction using a carbonic acid diester is carried out by heating and stirring a specified ratio of diol components with a carbonic acid diester in an inert gas atmosphere, and distilling off the resulting alcohol or phenols. The reaction temperature varies depending on the boiling point of the resulting alcohol or phenols, but is usually in the range of 120 to 350°C. The reaction is completed by reducing the pressure from the beginning and distilling off the resulting alcohol or phenols. If necessary, a terminal terminator, antioxidant, etc. may also be added.

The carbonic acid diester used in the transesterification reaction includes esters of aryl groups and aralkyl groups having 6 to 12 carbon atoms, which may be substituted. Specific examples include diphenyl carbonate, ditolyl carbonate, bis(chlorophenyl) carbonate, and m-cresyl carbonate. Of these, diphenyl carbonate is particularly preferred. The amount of diphenyl carbonate used is preferably 0.97 to 1.10 moles, more preferably 1.00 to 1.06 moles, per mole of the total of the diol components.

In the melt polymerization method, a polymerization catalyst can be used to increase the polymerization rate. Examples of such a polymerization catalyst include alkali metal compounds, alkaline earth metal compounds, nitrogen-containing compounds, and metal compounds.

Such compounds include organic and inorganic salts of alkali metals and alkaline earth metals,
Oxides, hydroxides, hydrides, alkoxides, quaternary ammonium hydroxides, etc. are preferably used, and these compounds can be used alone or in combination.

Examples of alkali metal compounds include sodium hydroxide, potassium hydroxide, cesium hydroxide, lithium hydroxide, sodium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, sodium acetate, potassium acetate, cesium acetate, lithium acetate, sodium stearate, potassium stearate, cesium stearate, lithium stearate, sodium borohydride, sodium benzoate, potassium benzoate, cesium benzoate, lithium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, disodium phenylphosphate, disodium, dipotassium, dicesium, and dilithium salts of bisphenol A, and sodium, potassium, cesium, and lithium salts of phenol.

Examples of alkaline earth metal compounds include magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, magnesium carbonate, calcium carbonate, strontium carbonate, barium carbonate, magnesium diacetate, calcium diacetate, strontium diacetate, barium diacetate, barium stearate, etc.

Examples of nitrogen-containing compounds include quaternary ammonium hydroxides having alkyl or aryl groups, such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and trimethylbenzylammonium hydroxide. Other examples include tertiary amines, such as triethylamine, dimethylbenzylamine, and triphenylamine, and imidazoles, such as 2-methylimidazole, 2-phenylimidazole, and benzimidazole. Other examples include bases or basic salts, such as ammonia, tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, and tetraphenylammonium tetraphenylborate.

Examples of metal compounds include zinc aluminum compounds, germanium compounds, organotin compounds, antimony compounds, manganese compounds, titanium compounds, zirconium compounds, etc. These compounds may be used alone or in combination of two or more.

The amount of these polymerization catalysts used is selected from the range of preferably 1×10 ⁻⁹ to 1×10 ⁻² equivalents, preferably 1×10 ⁻⁸ to 1×10 ⁻⁵ equivalents, more preferably 1×10 ⁻⁷ to 1×10 ⁻³ equivalents per mole of the diol component.

A catalyst deactivator can also be added in the later stages of the reaction. Known catalyst deactivators are effectively used as catalyst deactivators, and among these, ammonium salts and phosphonium salts of sulfonic acid are preferred. Furthermore, salts of dodecylbenzenesulfonic acid such as tetrabutylphosphonium salt of dodecylbenzenesulfonic acid, and salts of paratoluenesulfonic acid such as tetrabutylammonium salt of paratoluenesulfonic acid are preferred.

As sulfonic acid esters, methyl benzenesulfonate, ethyl benzenesulfonate, butyl benzenesulfonate, octyl benzenesulfonate, phenyl benzenesulfonate, methyl paratoluenesulfonate, ethyl paratoluenesulfonate, butyl paratoluenesulfonate, octyl paratoluenesulfonate, phenyl paratoluenesulfonate, etc. are preferably used. Among these, tetrabutylphosphonium dodecylbenzenesulfonate is most preferably used.

When at least one polymerization catalyst selected from alkali metal compounds and/or alkaline earth metal compounds is used, the amount of the catalyst deactivator used is preferably 0.5 to 50 mol, more preferably 0.5 to 10 mol, and further preferably 0.8 to 5 mol, per mol of the catalyst.

(Branching Agent)
In the polycarbonate resin produced by the present invention, a compound having three or more functional groups in one molecule can be used as a branching agent to improve the blow moldability. As the functional group, a compound containing a hydroxyl group, a carboxyl group, a carboxylate group, a carbonyl group, an amino group, or an imino group is preferable. Specifically, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,2,6-hexanetriol, 2,5-dimethyl-1.2.6-hexanetriol, dipentaerythritol, trimethylolethane, trimethylolpropane, 1,3,5-cyclohexanetriol phloroglucin, mellitic acid, trimellitic acid chloride, trimellitic anhydride, gallic acid, n-propyl gallate, protocatechuic acid, pyromellitic acid, pyromellitic acid secondary anhydride, α-resorcinol, acid, β-resorcylic acid, resorcinaldehyde, trimellityl chloride, trimethyl trichloride, 4-chloroformylphthalic anhydride, benzophenonetetracarboxylic acid, 2,4,4'-trihydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,4,4'-trihydroxyphenyl ether, 2,2',4,4'-tetrahydroxyphenyl ether, 2,4,4'-trihydroxydiphenyl-2-propane, 2,2'-bis(2,4-dihydroxy)propane, 2,2',4,4'-tetrahydroxydiphenylmethane, 2,4,4'-trihydroxydiphenylmethane, 1-[α-methyl-α-(4'-hydroxyphenyl)ethyl]-4-[α',α'-bis(4'-hydroxyphenyl)ethyl]benzene, α,α',α'-tris( 4-hydroxyphenyl)-1,3,5-triisopropylbenzene, 2,6-bis(2'-hydroxy-5'-methylbenzyl)-4-methylphenol, 4,6-dimethyl-2,4,6-tris(4'-hydroxyphenyl)-heptene-2, 4,6-dimethyl-2,4,6-tris(4'-hydroxyphenyl)-heptane-2, 1,3,5-tris(4'-hydroxyphenyl)-benzene, 1,1,1-tris(4'-hydroxyphenyl)-ethane, 1,1,1-tris(4-hydroxy-3-methylphenyl)ethane, 1,1,1-tris(4-hydroxy-3,5-dimethylphenyl)ethane, 2,2-bis[4,4-bis(4'-hydroxyphenyl)cyclohexyl]-propane, 2,6-bis(2'-hydroxy-5'-isopropylbenzyl)-4-isopropylphenol phenol, bis[2-hydroxy-3-(2'-hydroxy-5'-methylbenzyl)-5-methylphenyl]methane, bis[2-hydroxy-3-(2'-hydroxy-5'-isopropylbenzyl)-5-methylphenyl]methane, tetrakis(4-hydroxyphenyl)methane, tris(4-hydroxyphenyl)phenylmethane, 2',4',7-trihydroxyflavan, 2,4,4-trimethyl-2',4',7-trihydroxyflavan, 1,3-bis(2',4'-dihydroxyphenylisopropyl)benzene, tris(4'-hydroxyaryl)-amyl-s-triazine, 1-[α-methyl-α-(4'-hydroxyphenyl)ethyl]-3-[α',α'-bis(4'-hydroxyphenyl)ethyl]benzene, isatin bis(O-cresol), and the like.

Among these, pentaerythritol, glycerin, 1,1,1-tris(4-hydroxyphenyl)ethane, 1,1,1-tris(4-hydroxy-3-methylphenyl)ethane, and 1,1,1-tris(4-hydroxy-3,5-dimethylphenyl)ethane are particularly preferred. Each of the branching agents may be used alone or in combination of two or more.

The lower limit of the 5% weight loss temperature of the branching agent is preferably 240°C or higher, more preferably 250°C or higher, and even more preferably 260°C or higher. If the 5% weight loss temperature is below 240°C, it will decompose during melt polymerization, and the desired melt strength will not be obtained or the color will deteriorate. The upper limit of the 5% weight loss temperature is 400°C or lower. A higher upper limit temperature is preferable, but the actual polymerization and molding temperatures are below 400°C, and compounds above 400°C tend to have a high molecular weight, making them undesirable as branching agents.

The branching agent is preferably present in an amount of 0.01 mol% to 3 mol% relative to the diol compound raw material. If it is less than 0.01 mol%, the effect of improving blow moldability is low, and if it is more than 3 mol%, gelation will proceed, which is not preferable.

(Terminal Structure)
The polycarbonate resin of the present invention obtained by carrying out the reaction as described above has a terminal structure of a diol group or a carbonate diester residue, but the polycarbonate resin used in the base polymer substrate of the present invention may have a terminal group introduced therein as long as the properties of the polycarbonate resin are not impaired. Such a terminal group can be introduced by adding a monohydroxy compound during polymerization. As the monohydroxy compound, a hydroxy compound represented by the following formula (2) or (3) is preferably used.

In the above formulas (2) and (3), R ⁴ is an alkyl group having 4 to 30 carbon atoms, an aralkyl group having 7 to 30 carbon atoms, a perfluoroalkyl group having 4 to 30 carbon atoms, or a group represented by the following formula (4):

, preferably an alkyl group having 4 to 20 carbon atoms, a perfluoroalkyl group having 4 to 20 carbon atoms, or the above formula (4), and particularly preferably an alkyl group having 8 to 20 carbon atoms, or the above formula (4). X is preferably at least one bond selected from the group consisting of a single bond, an ether bond, a thioether bond, an ester bond, an amino bond, and an amide bond, more preferably at least one bond selected from the group consisting of a single bond, an ether bond, and an ester bond, and of these, a single bond or an ester bond is preferred. a is an integer of 1 to 5, preferably an integer of 1 to 3, and particularly preferably 1.

In the formula (4), R ⁵ , R ⁶ , R ⁷ , R ⁸ and R ⁹ are each independently at least one group selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms and an aralkyl group having 7 to 20 carbon atoms, preferably at least one group selected from the group consisting of an alkyl group having 1 to 10 carbon atoms and an aryl group having 6 to 10 carbon atoms, and more preferably at least one group selected from the group consisting of a methyl group and a phenyl group. b is an integer of 0 to 3, preferably an integer of 1 to 3, and more preferably an integer of 2 to 3. c is an integer of 4 to 100, preferably an integer of 4 to 50, and more preferably an integer of 8 to 50.

The monohydroxy compounds used in the present invention are also preferably raw materials obtained from renewable resources such as plants. Examples of monohydroxy compounds obtained from plants include long-chain alkyl alcohols having 14 or more carbon atoms (cetanol, stearyl alcohol, behenyl alcohol) obtained from vegetable oils.

<Characteristics of polycarbonate resin>
(Specific viscosity: η _SP )
The specific viscosity (η _SP ) of the polycarbonate resin used in the present invention is preferably in the range of 0.23 to 0.60, more preferably in the range of 0.25 to 0.55, further preferably in the range of 0.30 to 0.50, and particularly preferably in the range of 0.35 to 0.45. When the specific viscosity is 0.23 or more, the strength of the molded product is excellent, and when it is 0.60 or less, the moldability during injection molding is good.

The specific viscosity in the present invention can be determined by using an Ostwald viscometer from a solution in which 0.7 g of polycarbonate resin is dissolved in 100 ml of methylene chloride at 20°C.
Specific viscosity (η _SP )=(t−t ₀ )/t ₀
[ _t0 is the number of seconds that methylene chloride falls, and t is the number of seconds that the sample solution falls]
The specific viscosity can be measured, for example, as follows: First, polycarbonate resin is dissolved in methylene chloride in an amount 20 to 30 times its weight, and the soluble matter is collected by filtration through Celite. The solution is then removed and the mixture is thoroughly dried to obtain a solid that is soluble in methylene chloride. 0.7 g of the solid is dissolved in 100 ml of methylene chloride, and the specific viscosity at 20°C is determined using an Ostwald viscometer.
The polycarbonate resin used in the present invention may be used in combination with other resins as long as the effects of the present invention are not impaired.

(impurities)
The amount of the diol compound contained in the polycarbonate resin is preferably 700 ppm or less, more preferably 500 ppm or less, and particularly preferably 200 ppm or less, in the reaction liquid at the outlet of the final polymerization reactor. The concentration of the carbonate diester in the polycarbonate resin used in the present invention is preferably 200 ppm or less, more preferably 100 ppm or less, particularly preferably 60 ppm or less, and of these, 30 ppm or less is suitable. These impurities can be reduced by controlling the degree of vacuum in the polymerization reaction.

<Block polymer (C)>
The polycarbonate resin composition of the present invention contains a block polymer (C) having a structure in which polyolefin blocks and polyether blocks are repeatedly and alternately bonded.

The polyether chain functions as a hydrophilic segment, and the inclusion of the polyether chain provides antistatic performance. The weight average molecular weight of the polyether chain is preferably 1,000 to 15,000 from the viewpoints of heat resistance and reactivity with the polyolefin chain. Such a block polymer can be obtained by, for example, a method described in JP-A-2001-278985 and JP-A-2003-48990, in which polypropylene or polyethylene is acid-modified and reacted with polyalkylene glycol.

Since the block polymer (C) used in the present invention exhibits antistatic properties by being dispersed in a polycarbonate resin, it is generally preferred that the surface resistance of the block polymer (C) itself is as low as possible. The surface resistance of such a block polymer is generally 1×10 ¹⁰ to 1×10 ⁴ Ω, but the surface resistance of the block polymer (C) used in the present invention is preferably 1×10 ⁹ to 1×10 ⁴ Ω, and more preferably 1×10 ⁸ to 1×10 ⁴ Ω.

To further improve the antistatic properties, antistatic agents other than the block polymers described above may be used in combination, if necessary.

Other antistatic agents that can be used include surfactants [anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, etc.], salts other than surfactant salts, and ionic liquids.

<Polycarbonate resin composition containing polycarbonate resin and block polymer (C)>
(Method for producing polycarbonate resin composition)
The polycarbonate resin composition of the present invention is preferably prepared by blending the polycarbonate resin and the antistatic agent containing the block polymer (C) in a molten state. As a method for blending in a molten state, an extruder is generally used, and the molten resin is kneaded at a temperature of 200 to 320°C, preferably 220 to 300°C, more preferably 230 to 290°C, and then pelletized. This provides pellets of a resin composition in which both resins are uniformly blended. The configuration of the extruder, the configuration of the screw, and the like are not particularly limited. If the molten resin temperature in the extruder exceeds 320°C, the resin may become discolored or may undergo thermal decomposition. On the other hand, if the resin temperature is below 200°C, the resin viscosity may be too high, causing an overload on the extruder.

(Weight ratio)
The block polymer (C) used in the present invention is blended in the range of 1 to 20 parts by weight per 100 parts by weight of the polycarbonate resin. The range is preferably 2 to 19 parts by weight, more preferably 3 to 18 parts by weight, even more preferably 5 to 16 parts by weight, and particularly preferably 8 to 15 parts by weight. By adjusting the range to the above range, a resin composition excellent in transparency, surface hardness, impact resistance, and antistatic properties can be obtained.

(Additives)
The polycarbonate resin composition used in the present invention may contain additives such as a heat stabilizer, a plasticizer, a light stabilizer, a polymerized metal deactivator, a flame retardant, a lubricant, a surfactant, an antibacterial agent, an ultraviolet absorber, a release agent, and a colorant, depending on the application and necessity.

(Heat stabilizer)
The polycarbonate resin composition used in the present invention preferably contains a heat stabilizer in particular in order to suppress the decrease in molecular weight and the deterioration of color during extrusion and molding. Examples of the heat stabilizer include phosphorus-based heat stabilizers, phenol-based heat stabilizers, and sulfur-based heat stabilizers, and these can be used alone or in combination of two or more. It is preferable to blend a phosphite compound as the phosphorus-based stabilizer. Examples of the phosphite compound include pentaerythritol-type phosphite compounds, phosphite compounds that react with dihydric phenols and have a cyclic structure, and phosphite compounds with other structures.

Specific examples of the pentaerythritol-type phosphite compounds include distearyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-ethylphenyl)pentaerythritol diphosphite, phenyl bisphenol A pentaerythritol diphosphite, bis(nonylphenyl)pentaerythritol diphosphite, dicyclohexyl pentaerythritol diphosphite, and the like. Among these, distearyl pentaerythritol diphosphite and bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite are preferred.

Examples of phosphite compounds that react with the above dihydric phenols to form a cyclic structure include 2,2'-methylenebis(4,6-di-tert-butylphenyl)(2,4-di-tert-butylphenyl)phosphite, 2,2'-methylenebis(4,6-di-tert-butylphenyl)(2-tert-butyl-4-methylphenyl)phosphite, 2,2'-methylenebis(4-methyl-6-tert-butylphenyl)(2-tert-butyl-4-methylphenyl)phosphite, Examples of such phosphite include 2,2'-ethylidenebis(4-methyl-6-tert-butylphenyl)(2-tert-butyl-4-methylphenyl)phosphite, 2,2'-methylene-bis-(4,6-di-t-butylphenyl)octylphosphite, and 6-tert-butyl-4-[3-[(2,4,8,10)-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl)oxy]propyl]-2-methylphenol.

Examples of phosphite compounds having the above other structures include triphenyl phosphite, tris(nonylphenyl)phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite, tris(diethylphenyl)phosphite, tris(di-iso-propylphenyl)phosphite, tris(di-n-butylphenyl)phosphite, tris(2,4-di-tert-butylphenyl)phosphite, and tris(2,6-di-tert-butylphenyl)phosphite.

In addition to various phosphite compounds, examples include phosphate compounds, phosphonite compounds, and phosphonate compounds.

Examples of phosphate compounds include tributyl phosphate, trimethyl phosphate, tricresyl phosphate, triphenyl phosphate, trichlorophenyl phosphate, triethyl phosphate, diphenyl cresyl phosphate, diphenyl monoorthoxenyl phosphate, tributoxyethyl phosphate, dibutyl phosphate, dioctyl phosphate, diisopropyl phosphate, etc., and preferably triphenyl phosphate and trimethyl phosphate.

Examples of the phosphonite compound include tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene diphosphonite, tetrakis(2,4-di-tert-butylphenyl)-4,3'-biphenylene diphosphonite, tetrakis(2,4-di-tert-butylphenyl)-3,3'-biphenylene diphosphonite, tetrakis(2,6-
di-tert-butylphenyl)-4,4'-biphenylene diphosphonite, tetrakis(2,6-di-tert-butylphenyl)-4,3'-biphenylene diphosphonite, tetrakis(2,6-di-tert-butylphenyl)-3,3'-biphenylene diphosphonite, bis(2,4-di-tert-butylphenyl)-4-phenyl-phenylphosphonite, bis(2,4-di-tert-butylphenyl)-3-phenyl-phenylphosphonite, bis(2,6-di-n-butylphenyl)-3-phenyl-phenylphosphonite, bis Examples of the phosphonite include (2,6-di-tert-butylphenyl)-4-phenyl-phenyl phosphonite and bis(2,6-di-tert-butylphenyl)-3-phenyl-phenyl phosphonite, with tetrakis(di-tert-butylphenyl)-biphenylene diphosphonite and bis(di-tert-butylphenyl)-phenyl-phenyl phosphonite being preferred, and tetrakis(2,4-di-tert-butylphenyl)-biphenylene diphosphonite and bis(2,4-di-tert-butylphenyl)-phenyl-phenyl phosphonite being more preferred. Such phosphonite compounds can be used in combination with the above-mentioned phosphite compounds having an aryl group substituted with two or more alkyl groups, and are therefore preferred.

Examples of phosphonate compounds include dimethyl benzenephosphonate, diethyl benzenephosphonate, and dipropyl benzenephosphonate.

Among the above phosphorus-based heat stabilizers, trisnonylphenyl phosphite, trimethyl phosphate, tris(2,4-di-tert-butylphenyl) phosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, and bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite are preferably used.

The above phosphorus-based heat stabilizers can be used alone or in combination of two or more kinds. The phosphorus-based heat stabilizer is preferably blended in an amount of 0.001 to 1 part by weight, more preferably 0.01 to 0.5 parts by weight, and even more preferably 0.01 to 0.3 parts by weight per 100 parts by weight of the polycarbonate resin composition.

The polycarbonate resin composition used in the present invention may contain a hindered phenol-based heat stabilizer or a sulfur-based heat stabilizer in combination with a phosphorus-based heat stabilizer to suppress a decrease in molecular weight or deterioration in color during extrusion and molding.

Examples of hindered phenol-based heat stabilizers include, but are not limited to, those that have an antioxidant function, such as n-octadecyl-3-(4'-hydroxy-3',5'-di-t-butylphenyl)propionate, tetrakis{methylene-3-(3',5'-di-t-butyl-4-hydroxyphenyl)propionate}methane, distearyl(4-hydroxy-3-methyl-5-t-butylbenzyl)malonate, triethylene glycol-bis{3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate}, 1,6-hexanediol-bis{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate}, pentaerythrityl-tetrakis{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate}, 2,2-thiazole-bis{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate}, tetrakis(methylene- ...) and tetrakis(methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate). diethylene bis{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate}, 2,2-thiobis(4-methyl-6-t-butylphenol), 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tris(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate, 2,4-bis{(octylthio (e)methyl)-o-cresol, isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 2,5,7,8-tetramethyl-2(4',8',12'-trimethyltridecyl)chroman-6-ol, 3,3',3",5,5',5"-hexa-t-butyl-a,a',a"-(mesitylene-2,4,6-triyl)tri-p-cresol, etc.

Among these, n-octadecyl-3-(4'-hydroxy-3',5'-di-t-butylphenyl)propionate, pentaerythrityl-tetrakis{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate}, 3,3',3",5,5',5"-hexa-t-butyl-a,a',a'-(mesitylene-2,4,6-triyl)tri-p-cresol, 2,2-thiodiethylenebis{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate}, etc. are preferred.

These hindered phenol-based heat stabilizers may be used alone or in combination of two or more.

The hindered phenol-based heat stabilizer is preferably blended in an amount of 0.001 to 1 part by weight, more preferably 0.01 to 0.5 parts by weight, and even more preferably 0.01 to 0.3 parts by weight per 100 parts by weight of the polycarbonate resin composition.

Examples of sulfur-based heat stabilizers include dilauryl-3,3'-thiodipropionate, ditridecyl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, laurylstearyl-3,3'-thiodipropionate, pentaerythritol tetrakis (3-laurylthiopropionate), bis[2-methyl-4-(3-laurylthiopropionyloxy)-5-tert-butylphenyl]sulfide, octadecyl disulfide, mercaptobenzimidazole, 2-mercapto-6-methylbenzimidazole, and 1,1'-thiobis(2-naphthol). Of the above, pentaerythritol tetrakis (3-laurylthiopropionate) is preferred.

These sulfur-based heat stabilizers may be used alone or in combination of two or more.

The sulfur-based heat stabilizer is preferably added in an amount of 0.001 to 1 part by weight, more preferably 0.01 to 0.5 parts by weight, and even more preferably 0.01 to 0.3 parts by weight per 100 parts by weight of the polycarbonate resin composition.

When using a combination of a phosphite-based heat stabilizer, a phenol-based heat stabilizer, and a sulfur-based heat stabilizer, the total amount of these is preferably 0.001 to 1 part by weight, more preferably 0.01 to 0.3 parts by weight, per 100 parts by weight of the polycarbonate resin composition.

(Release Agent)
The polycarbonate resin composition used in the present invention may contain a mold release agent in order to further improve releasability from a mold during melt molding, within the scope of the present invention.

Such release agents include higher fatty acid esters of monohydric or polyhydric alcohols, higher fatty acids, paraffin wax, beeswax, olefin waxes, olefin waxes containing carboxy groups and/or carboxylic anhydride groups, silicone oils, organopolysiloxanes, etc.

The higher fatty acid ester is preferably a partial or full ester of a monohydric or polyhydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms. Examples of such partial or full esters of a monohydric or polyhydric alcohol and a saturated fatty acid include stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, stearate monosorbitate, stearyl stearate, behenic acid monoglyceride, behenyl behenate, pentaerythritol monostearate, pentaerythritol tetrastearate, pentaerythritol tetrapelargonate, propylene glycol monostearate, stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, biphenyl biphenate, sorbitan monostearate, 2-ethylhexyl stearate, and the like.

Among these, stearic acid monoglyceride, stearic acid triglyceride, pentaerythritol tetrastearate, and behenyl behenate are preferably used.

As the higher fatty acid, a saturated fatty acid having 10 to 30 carbon atoms is preferable. Examples of such fatty acids include myristic acid, lauric acid, palmitic acid, stearic acid, and behenic acid.

These release agents may be used alone or in combination of two or more. The amount of such release agent is preferably 0.01 to 5 parts by weight per 100 parts by weight of the polycarbonate resin composition.

(Ultraviolet absorber)
The polycarbonate resin composition used in the present invention may contain an ultraviolet absorber, such as a benzotriazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, a triazine-based ultraviolet absorber, a cyclic iminoester-based ultraviolet absorber, or a cyanoacrylate-based ultraviolet absorber, and among these, a benzotriazole-based ultraviolet absorber is preferred.

Benzotriazole-based ultraviolet absorbers include, for example, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-amylphenyl)benzotriazole, 2-(2'-hydroxy-3'-dodecyl-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-bis(α,α'-dimethylbenzyl)phenylbenzotriazole, 2-[2'-hydroxy Benzotriazole-based ultraviolet absorbers such as benzotriazole-based ultraviolet absorbers are typified by 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2,2'methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], and methyl-3-[3-tert-butyl-5-(2H-benzotriazol-2-yl)-4-hydroxyphenylpropionate-polyethylene glycol condensate.

The proportion of such ultraviolet absorbers is preferably 0.01 to 2 parts by weight, more preferably 0.1 to 1 part by weight, and even more preferably 0.2 to 0.5 parts by weight, per 100 parts by weight of the polycarbonate resin composition.

(Light stabilizer)
The polycarbonate resin composition used in the present invention may contain a light stabilizer. The inclusion of a light stabilizer has the advantages of being excellent in terms of weather resistance and making molded products less susceptible to cracking.

Examples of light stabilizers include 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, didecanoic acid bis(2,2,6,6-tetramethyl-1-octyloxy-4-piperidinyl) ester, bis(1,2,2,6,6-pentamethyl-4-piperidinyl)-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]butyl malonate, 2,4-bis[N-butyl-N-(1-cyclohexyloxy-2,2,6,6-tetramethyloxy)phenyl]methyl]butyl malonate, tetramethylpiperidin-2-yl)amino]-6-(2-hydroxyethylamine)-1,3,5-triazine, bis(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, methyl(1,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)carbonate, bis(2,2,6,6-tetramethyl-4-piperidyl)succinate, bis(2,2,6,6-tetramethyl-4 -piperidyl) sebacate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 4-octanoyloxy-2,2,6,6-tetramethylpiperidine, bis(2,2,6,6-tetramethyl-4-piperidyl)diphenylmethane-p,p'-dicarbamate, bis(2,2,6,6-tetramethyl-4-piperidyl)benzene-1,3-disulfonate, bis(2,2,6,6-tetramethyl-4-piperidyl)phenylphosphite, and the like. Examples of such light stabilizers include nickel complexes such as diamines, nickel bis(octylphenyl sulfide, nickel complex-3,5-di-t-butyl-4-hydroxybenzyl phosphate monoethylate, and nickel dibutyl dithiocarbamate. These light stabilizers may be used alone or in combination of two or more. The content of the light stabilizer is preferably 0.001 to 1 part by weight, more preferably 0.01 to 0.5 parts by weight, per 100 parts by weight of the polycarbonate resin composition.

(Epoxy stabilizer)
In order to improve hydrolysis resistance, the polycarbonate resin composition used in the present invention may contain an epoxy compound within a range that does not impair the object of the present invention.

Epoxy stabilizers include epoxidized soybean oil, epoxidized linseed oil, phenyl glycidyl ether, allyl glycidyl ether, t-butylphenyl glycidyl ether, 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-3',4'-epoxy-6'-methylcyclohexyl carboxylate, 2,3-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate, 4-(3,4-epoxy-5-methylcyclohexyl)butyl-3',4'-epoxycyclohexyl carboxylate, 3,4-epoxycyclohexylethylene oxide, cyclohexylmethyl-3,4-epoxycyclohexylcarboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-6'-methylcyclohexylcarboxylate, bisphenol A diglycidyl ether, tetrabromobisphenol A glycidyl ether, diglycidyl ester of phthalic acid, diglycidyl ester of hexahydrophthalic acid, bis-epoxydicyclopentadienyl ether, bis-epoxyethylene glycol, bis-epoxycyclohexyl adipate, butadiene diepoxide, tetrafluoroethylene glycol ... phenylethylene epoxide, octyl epoxythalate, epoxidized polybutadiene, 3,4-dimethyl-1,2-epoxycyclohexane, 3,5-dimethyl-1,2-epoxycyclohexane, 3-methyl-5-t-butyl-1,2-epoxycyclohexane, octadecyl-2,2-dimethyl-3,4-epoxycyclohexyl carboxylate, N-butyl-2,2-dimethyl-3,4-epoxycyclohexyl carboxylate, cyclohexyl-2-methyl-3,4-epoxycyclohexyl carboxylate, N-butyl-2-isopropyl-3,4-epoxy-5-methylcyclohexyl carboxylate, octadecyl-3,4-epoxycyclohexyl carboxylate, 2-ethylhexyl-3',4'-epoxycyclohexyl carboxylate, 4,6-dimethyl-2,3-epoxycyclohexyl-3',4'-epoxycyclohexyl carboxylate, 4,5-epoxy tetrahydrophthalic anhydride, 3-t-butyl-4,5-epoxy tetrahydrophthalic anhydride, diethyl-4,5-epoxy-cis-1,2-cyclohexyl dicarboxylate, di-n-butyl-3-t-butyl-4,5-epoxy-cis-1,2-cyclohexyl dicarboxylate, etc. Bisphenol A diglycidyl ether is preferred in terms of compatibility, etc.

It is desirable to mix such epoxy stabilizers in an amount of 0.0001 to 5 parts by weight, preferably 0.001 to 1 part by weight, and more preferably 0.005 to 0.5 parts by weight, per 100 parts by weight of the polycarbonate resin composition.

(Bluing agent)
The polycarbonate resin composition used in the present invention can be blended with a bluing agent to eliminate the yellow color of the lens due to the polymer or ultraviolet absorbing agent. As the bluing agent, any agent that is used for polycarbonate can be used without any problem. In general, anthraquinone dyes are easily available and are preferred.

Specific examples of bluing agents include Solvent Violet 13 (CA. No. (Color Index No.) 60725), Solvent Violet 31 (CA. No. 68210), Solvent Violet 33 (CA. No. 60725), Solvent Blue 94 (CA. No. 61500), Solvent Violet 36 (CA. No. 68210), Solvent Blue 97 (Bayer's "Macrolex Violet RR"), and Solvent Blue 45 (CA. No. 61110).

These bluing agents may be used alone or in combination of two or more. These bluing agents are preferably mixed in an amount of 0.1×10 ⁻⁴ to 2×10 ⁻⁴ parts by weight per 100 parts by weight of the polycarbonate resin composition.

(Flame retardant)
The polycarbonate resin composition used in the present invention can also be blended with a flame retardant. Examples of the flame retardant include halogen-based flame retardants such as brominated epoxy resin, brominated polystyrene, brominated polycarbonate, brominated polyacrylate, and chlorinated polyethylene, phosphate-based flame retardants such as monophosphate compounds and phosphate oligomer compounds, organic phosphorus-based flame retardants other than phosphate-based flame retardants such as phosphinate compounds, phosphonate compounds, phosphonitrile oligomer compounds, and phosphonic acid amide compounds, organic metal salt-based flame retardants such as organic sulfonic acid alkali (earth) metal salts, boric acid metal salt-based flame retardants, and stannic acid metal salt-based flame retardants, as well as silicone-based flame retardants, ammonium polyphosphate-based flame retardants, and triazine-based flame retardants. In addition, flame retardant assistants (e.g., sodium antimonate, antimony trioxide, etc.) and drip prevention agents (polytetrafluoroethylene having fibril forming ability, etc.) may be blended and used in combination with the flame retardant.

Among the flame retardants mentioned above, compounds that do not contain chlorine or bromine atoms are more suitable as flame retardants for the molded article of the present invention, which is characterized by its reduced environmental impact, because they reduce factors that are considered undesirable when incinerating or thermally recycling the material.

When a flame retardant is added, the amount is preferably in the range of 0.05 to 50 parts by weight per 100 parts by weight of the polycarbonate resin composition. At 0.05 parts by weight or more, sufficient flame retardancy is easily achieved, and at 50 parts by weight or less, the strength and heat resistance of the molded product are excellent.

(Molded products)
The polycarbonate resin composition of the present invention can be molded and processed into a molded product (including a sheet or film) by any method such as injection molding, compression molding, injection compression molding, melt film forming, casting, etc., and can be used as a molded product such as an optical lens, an optical disk, an optical film, a plastic substrate, an optical card, a liquid crystal panel, a headlamp lens, a light guide plate, a diffusion plate, a protective film, an OPC binder, a front panel, a housing, a tray, a water tank, a lighting cover, a signboard, a resin window, etc. In particular, it can be used as a member requiring a high surface hardness, such as a front panel, a housing, a tray, a water tank, a lighting cover, a signboard, a resin window, etc.

(Transparency)
The haze of a 2 mm-thick molded piece of the polycarbonate resin composition of the present invention is preferably 40 or less, more preferably 35 or less, even more preferably 30 or less, and particularly preferably 25 or less. When the haze is within the above range, the range of use as an optical member is not limited, which is preferable.

(Impact Strength)
The polycarbonate resin composition of the present invention preferably has a notched Charpy impact strength of 8 kJ/m2 ^{or more} , more preferably 10 kJ/m2 ^{or more} , and even more preferably 12 kJ/m2 or ^more , measured in accordance with ISO 179. Note that a notched Charpy impact strength of 100 kJ/m2 ^{or less} provides sufficient functionality.

(Pencil hardness)
The polycarbonate resin composition of the present invention preferably has a pencil hardness of B or more. In terms of being more excellent in scratch resistance, it is more preferable that the hardness is HB or more. The pencil hardness has sufficient function with a pencil hardness of 4H or less. In the present invention, the pencil hardness means a hardness at which no scratch marks remain when the polycarbonate resin composition of the present invention is scratched with a pencil having a specific pencil hardness, and it is preferable to use the pencil hardness used in the surface hardness test of a coating film that can be measured according to JIS K-5600 as an index. The pencil hardness becomes softer in the order of 9H, 8H, 7H, 6H, 5H, 4H, 3H, 2H, H, F, HB, B, 2B, 3B, 4B, 5B, and 6B, with the hardest being 9H and the softest being 6B.

(Antistatic properties)
The polycarbonate resin composition of the present invention preferably has a surface resistivity of 1×10 ¹⁵ Ω/□ or less, more preferably 1×10 14 Ω/□ or less, and even more preferably 1×10 ¹³ Ω/□ or less, as measured using a high resistance resistivity meter MCP-HT450 manufactured by Mitsubishi Chemical Analytical Corporation at a measurement voltage of ¹⁰⁰⁰ V.

(Surface Treatment)
Molded articles formed from the resin composition of the present invention can be subjected to various surface treatments. The surface treatment referred to here is a method for forming a new layer on the surface of a resin molded article, such as vapor deposition (physical vapor deposition, chemical vapor deposition, etc.), plating (electroplating, electroless plating, hot-dip plating, etc.), painting, coating, printing, etc., and any commonly used method can be applied. Specific examples of the surface treatment include various surface treatments such as hard coat, water-repellent/oil-repellent coat, ultraviolet absorbing coat, infrared absorbing coat, and metallizing (vapor deposition, etc.). Hard coat is a particularly preferred and necessary surface treatment.

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. In the examples, "parts" means "parts by weight." The resins and evaluation methods used in the examples are as follows.

1. Polymer composition ratio (NMR)
Each repeating unit was measured by proton NMR using JNM-AL400 manufactured by JEOL Ltd., and the polymer composition ratio (molar ratio) was calculated.

2. Specific Viscosity: Measured using an Ostwald viscometer from a solution prepared by dissolving 0.7 g of polycarbonate resin in 100 ml of methylene chloride at 20°C.
Specific viscosity (η _SP )=(t−t ₀ )/t ₀
[ _t0 is the number of seconds that methylene chloride falls, and t is the number of seconds that the sample solution falls]

3. Haze A 2 mm thick portion of the three-stage plate obtained by the following method was measured using a haze meter 300A manufactured by Nippon Denshoku Industries Co., Ltd.

4. Notched Charpy Impact Strength The notched Charpy impact strength of the ISO bending test pieces obtained by the following method was measured in accordance with ISO 179.

5. Pencil Hardness Based on JIS K-5600, a line was drawn on the surface of a molded article in a thermostatic chamber at an atmospheric temperature of 23° C. with a pencil held at a 45° angle and a load of 750 g applied, and the surface condition was visually evaluated.

6. Antistatic performance A flat plate of 45 mm length x 50 mm width x 2 mm thickness obtained under the same conditions as the method described below was conditioned for one week in an environment of 23°C and 50% humidity. After that, the surface resistivity (Ω/□) of the molded product was measured using a resistivity meter (high resistance resistivity meter MCP-HT450 manufactured by Mitsubishi Chemical Analyc Corporation) at a measurement voltage of 1000 V. The smaller the value, the better the antistatic performance.

[Polycarbonate resin (A)]
PC-1 (Example):
Structural units derived from ISS/structural units derived from ND=88/12 (mol %), specific viscosity 0.366
PC-2 (Example):
Structural units derived from isosorbide (hereinafter referred to as ISS)/structural units derived from 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane (hereinafter referred to as SPG)/structural units derived from 1,9-nonanediol (hereinafter referred to as ND)=72/21/7 (mol %), specific viscosity 0.396
PC-3 (Example)
Structural units derived from ISS/structural units derived from 1,4-cyclohexanedimethanol (hereinafter referred to as CHDM)=70/30 (mol %), specific viscosity 0.378
PC-4 (Comparative Example)
Aromatic polycarbonate resin having structural units derived from bisphenol A, L-1225WP manufactured by Teijin Limited

[Antistatic Agent (C)]
C-1 (Example): Block polymer having a structure in which polyolefin blocks and polyether blocks are repeatedly and alternately bonded. PELECTRON PVL (surface resistance: 3×10 ⁶ Ω) manufactured by Sanyo Chemical Industries, Ltd.
C-2 (Example): Block polymer having a structure in which polyolefin blocks and polyether blocks are repeatedly and alternately bonded. Pelestat 230 (Sanyo Chemical Industries, Ltd.) (Surface resistance: 5×10 ⁷ Ω)
C-3 (Example): Block polymer having a structure in which polyolefin blocks and polyether blocks are repeatedly and alternately bonded. Pelestat 300 (Sanyo Chemical Industries, Ltd.) (Surface resistance: 1×10 ⁸ Ω)
C-4 (Comparative Example): Block polymer having a structure in which a polyamide block and a polyether block are ester-bonded. Pelestat NC6321 (Surface resistance: 1×10 ⁹ Ω) manufactured by Sanyo Chemical Industries, Ltd.

[Example 1]
<Production of polycarbonate resin>
450 parts of isosorbide (hereinafter abbreviated as ISS), 67 parts of 1,9-nonanediol (hereinafter abbreviated as ND), 750 parts of diphenyl carbonate (hereinafter abbreviated as DPC), and 0.0033 parts of barium stearate as a catalyst were heated to 150°C under a nitrogen atmosphere and melted. Thereafter, the mixture was sent to a reaction vessel, and the heat transfer medium temperature of the condenser was adjusted to 40°C, the internal resin temperature was adjusted to 170°C, and the degree of vacuum was adjusted to 13.4 kPa over 30 minutes. Thereafter, the degree of vacuum was adjusted to 3.4 kPa over 20 minutes, and the temperature was maintained for 10 minutes. The degree of vacuum was further reduced to 0.9 kPa over 30 minutes, the internal temperature of the resin was adjusted to 220°C, and the temperature was maintained for 10 minutes. After that, the degree of vacuum was reduced to 0.2 kPa, and the resin temperature was increased from 220°C to 240°C over 30 minutes. After the resin reached a specified viscosity, the resin was discharged from the bottom of the reaction tank under nitrogen pressure, and while being cooled in a water tank, the resin was cut with a pelletizer to obtain pellets (PC-1).

<Production of polycarbonate resin composition>
Polycarbonate resin PC-1 and block polymer C-1 were mixed at a weight ratio of 90:10 and then fed to an extruder. Extrusion was performed using a vented twin-screw extruder with a diameter of 30 mmφ [Kobe Steel Works, Ltd. KTX-30], with a screw rotation speed of 150 rpm, a discharge rate of 20 kg/h, and a vent vacuum of 3 kPa to obtain pellets by melt kneading. The extrusion temperature was 250°C from the feed port to the die. A part of the obtained pellets was dried in a hot air circulation dryer at 90°C for 6 hours or more, and then molded using an injection molding machine at a cylinder temperature of 250°C and a mold temperature of 60°C to form test pieces for evaluation (ISO bending test pieces (compliant with ISO178, ISO179, ISO75-1 and ISO75-2), three-stage plates (1 mmt, 2 mmt, 3 mmt)) and flat plates with a length of 45 mm, a width of 50 mm, and a thickness of 2 mmt. The evaluation results are shown in Table 1.

[Example 2]
<Production of polycarbonate resin composition>
Except for changing the type of block polymer C and extruding at a ratio of PC-1:C-2=90:10, the same operations and evaluations were carried out as in Example 1. The results are shown in Table 1.

[Example 3]
<Production of polycarbonate resin composition>
Except for changing the type of block polymer C and extruding at a ratio of PC-1:C-3=90:10, the same operations and evaluations were carried out as in Example 1. The results are shown in Table 1.

[Example 4]
<Production of polycarbonate resin>
364 parts of isosorbide (hereinafter abbreviated as ISS), 221 parts of 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane (hereinafter abbreviated as SPG), 39 parts of 1,9-nonanediol (hereinafter abbreviated as ND), 750 parts of diphenyl carbonate (hereinafter abbreviated as DPC), and 0.8×10 ⁻² parts of tetramethylammonium hydroxide and 0.6×10 ⁻⁴ parts of barium stearate as catalysts were heated to 200° C. under a nitrogen atmosphere and melted. Thereafter, the temperature was raised to 220° C. over 30 minutes and the degree of vacuum was adjusted to 20.0 kPa. Thereafter, the temperature was raised to 240° C. over another 30 minutes and the degree of vacuum was adjusted to 10 kPa. After maintaining the temperature for 10 minutes, the degree of vacuum was reduced to 133 Pa or less over 1 hour. After the reaction was completed, the reaction mixture was discharged from the bottom of the reaction tank under nitrogen pressure, and while being cooled in a water tank, it was cut with a pelletizer to obtain pellets (PC-2).
<Production of polycarbonate resin composition>
Except for changing the type of polycarbonate and extruding at a ratio of PC-2:C-1=90:10, the same operations as in Example 1 were carried out and the same evaluations were carried out. The results are shown in Table 1.

[Example 5]
The same operations and evaluations as in Example 1 were carried out, except that 354 parts of ISS, 150 parts of CHDM, and 750 parts of DPC were used as raw materials (PC-3). The results are shown in Table 1.

[Example 6]
<Production of polycarbonate resin composition>
Except for the fact that the blend weight ratio was PC-1:C-1=97:3, the same operations and evaluations were carried out as in Example 1. The results are shown in Table 1.

[Example 7]
<Production of polycarbonate resin composition>
Except for the fact that the blend weight ratio was PC-1:C-1=85:15, the same operations and evaluations were carried out as in Example 1. The results are shown in Table 1.

[Comparative Example 1]
<Production of polycarbonate resin composition>
Except for changing the type of block polymer C and extruding at a ratio of PC-1:C-4=90:10, the same operations and evaluations were carried out as in Example 1. The results are shown in Table 2.

[Comparative Example 2]
<Production of polycarbonate resin composition>
Polycarbonate resin PC-4 and block polymer C-1 were mixed at a weight ratio of 90:10 and then fed to an extruder. For extrusion, a vented twin-screw extruder with a diameter of 30 mm [Kobe Steel Works, Ltd. KTX-30] was used, and the mixture was melt-kneaded at a screw speed of 150 rpm, a discharge rate of 20 kg/h, and a vent vacuum of 3 kPa to obtain pellets. The extrusion temperature was 280°C from the feed port to the die. A portion of the obtained pellets was dried in a hot air circulation dryer at 120°C for 6 hours or more, and then molded into test pieces for evaluation (ISO bending test pieces (compliant with ISO178, ISO179, ISO75-1 and ISO75-2), three-stage plates (1 mmt,
The evaluation results are shown in Table 2.

[Comparative Example 3]
<Production of polycarbonate resin composition>
Except for changing the type of block polymer C and extruding at a ratio of PC-4:C-4=90:10, the same operation as in Comparative Example 2 was carried out. As a result, melt extrusion was not possible.

[Comparative Example 4]
<Production of polycarbonate resin composition>
Except for extruding PC-1, the same procedures and evaluations were carried out as in Example 1. The results are shown in Table 2.

[Comparative Example 5]
<Production of polycarbonate resin composition>
Except for the fact that the blend weight ratio was PC-1:C-1=80:20, the same operations and evaluations were carried out as in Example 1. The results are shown in Table 2.

The polycarbonate resin composition of the present invention is useful as a component for optical lenses, optical disks, optical films, plastic substrates, optical cards, liquid crystal panels, headlamp lenses, light guide plates, diffusion plates, protective films, OPC binders, front panels, housings, trays, aquariums, lighting covers, signs, plastic windows, etc.

Claims (7)

A polycarbonate resin composition comprising: 100 parts by weight of a polycarbonate resin which contains 40 mol % or more of structural units (A) represented by the following formula (A) out of 100 mol % of all structural units; and further contains structural units (B) represented by the following formula (B); the sum of structural units (A) and structural units (B) out of 100 mol % of all structural units is 80 mol % or more ; and a block polymer (C) having a structure in which 1 to 20 parts by weight of a polyolefin block and a polyether block are repeatedly and alternately bonded to each other.
(In the formula, W represents at least one group selected from the group consisting of an alkylene group having 2 to 30 carbon atoms, a cycloalkylene group having 6 to 30 carbon atoms, and a heterocycle-containing alkylene group having 6 to 30 carbon atoms.) 2. The polycarbonate resin composition according to claim 1 , wherein a haze of a test piece having a thickness of 2 mm is 40 or less. 3. The polycarbonate resin composition according to claim 1 or 2, which has a Charpy notched impact strength measured in accordance with ISO 179 of 8 kJ/ ^m2 or more. 4. The polycarbonate resin composition according to claim 1, which has a pencil hardness of B or more as measured according to JIS K-5600. 5. The polycarbonate resin composition according to claim 1, wherein the surface resistivity of a molded product is 1×10 ¹⁵ (Ω/□) or less. A molded article obtained by molding the polycarbonate resin composition according to any one of claims 1 to 5 . A film or sheet formed from the polycarbonate resin composition according to any one of claims 1 to 5 .