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[0123] For example, static mixers or other dynamic mixers leading to homogenic mixing in, such as, for example, extrud› ers, are suitable for effectively mixing in the inhibitor. 

[0124] One or more aliphatic hydroxydicarboxylic acid(s) and/or hydroxypolycarboxylic acid(s) or derivative( s) thereof are added to the reaction mixture (reaction mixture melt) in or after the last reaction stage of the process according to the invention. The addition is accordingly preferably effected in the so-called finish reactor or after the finish reactor, particu› larly preferably after the finish reactor. 

[0125] According to the invention, aliphatic hydroxypoly› carboxylic acid(s) are to be understood as meaning those having more than two carboxyl groups. In the context of the invention, aliphatic hydroxypolycarboxylic acid(s) are pref› erably those having three, four or five carboxyl groups. Par› ticularly preferred aliphatic hydroxypolycarboxylic acids are aliphatic hydroxytricarboxylic acids. 

[0126] In preferred embodiments, one or more aliphatic hydroxydicarboxylic acid(s) and/or hydroxytricarboxylic acid(s) or derivative(s) thereof are added to the reaction mix› ture. 

[0127] Derivatives of aliphatic hydroxydicarboxylic acid (s) and/or hydroxypolycarboxylic acid(s) are to be under› stood as meaning, for example, salts, esters, amides, halides or anhydrides of the corresponding acids, preferably esters of the corresponding acids, or carboxylic acids derivatized at the hydroxyl group, such as, for example, alkoxycarboxylic acids. 

[0128] Preferred aliphatic hydroxydicarboxylic acids and/ or hydroxypolycarboxylic acids or derivatives thereof are, for example, those of the general formulae (VI) and (VII), respectively, 

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in which 

[0129] R 1 , R 2 , R 3 , independently of one another, represent a linear or branched, preferably a linear, C$_{1 }$-C$_{10}$-alkylene radical, particularly preferably a linear or branched, pref› erably linear, C$_{1 }$-Ccalkylene radical, 1 2 3 

[0130] X , X , X , independently of one another, represent Hor OH, at least one of the radicals X 1, X 2 , X $^{3 }$representing OH, 

[0131] W represents H, COOH, a carboxylate or alkylcar› boxyl, preferably COOH, 

[0132] n represents an integer from 1 to 3, preferably 1, 

[0133] m represents O or an integer from 1 to 3, preferably 0 or 1, 

[0134] o represents O or an integer from 1 to 3, preferably 0 or 1, 4 5 

[0135] R , R , independently of one another, represent a linear or branched C$_{1 }$-C$_{10}$-alkyl radical, preferably a linear 

(VI) 

(VII) 

or branched C$_{1 }$-Ccalkyl radical, or an alkali metal cation, preferably Li+, Na+ or K+, particularly preferably a linear or branched C$_{1 }$-Ccalkyl. 

[0136] Particularly preferred aliphatic hydroxydicarboxy› lic acids and/or hydroxypolycarboxylic acids or derivatives thereof are, for example, malic acid, malic acid esters, malic acidmonoesters, tartaric acid, tartaric acid esters, tartaric acid monoesters, hydroxymalonic acid or esters thereof, citric acid or esters thereof. All stereoisomers, mixtures of the stereoi› somers or racemic mixtures and also mixtures of the above› mentioned acids or esters are suitable and are within the scope of the invention. Tartaric acid or malic acid or derivatives thereof or mixtures of these are particularly preferred. 

[0137] The aliphatic hydroxydicarboxylic acids and/or hydroxypolycarboxytic acids or derivatives thereof are used, for example, in amounts of 5 to 500 ppm, preferably 10 to 300 ppm, particularly preferably 20 to 200 ppm, based on the polycarbonate, in or after the last reaction stage of the process according to the invention. 

[0138] By this combination of the addition of at least one inhibitor in a reaction stage before the last reaction stage and the addition of at least one aliphatic hydroxydicarboxylic acid and/or hydroxypolycarboxylic acid or a derivative thereof in the last reaction stage, it is possible to obtain by means of melt transesterification processes polycarbonates which lead to shaped articles having low buildup of electrostatic charge on the surface during further processing, for example by means of injection moulding. Such a combination of inhibitors and additional aliphatic hydroxydicarboxylic acids and/or hydroxypolycarboxylic acids or derivatives thereof in this specific time sequence within the process has not been described to date in the literature. The effect of the low buildup of electrostatic charge with little local variation on the surface of the resulting mouldings or extrudates is all the more surprising since, for example, the addition of inhibitors of the abovementioned type before the finish reactor without the additional addition of at least one aliphatic hydroxydicar› boxylic acid and/or hydroxypolycarboxylic acid or a deriva› tive thereof in the last reaction stage is already known ( cf. for example EP-A 1 612 231 and DE-A 103 57 161) but has no positive effect at all on the electrostatic properties of the resulting mouldings or extrudates. 

[0139] The process according to the invention can be car› ried out batchwise or continuously. 

[0140] After the dihydroxyaryl compounds and diary! car› bonates, optionally with further compounds, such as, for example, a higher-boiling monohydroxyaryl compound, are present as a melt, the reaction is started in the presence of at least one suitable catalyst. The conversion or the molecular weight is increased with increasing temperatures and decreasing pressures in suitable apparatuses and devices by removing the monohydroxyaryl compound which is being eliminated until the desired end state, i.e. the desired conver› sion or the desired molecular weight, is reached. Through the choice of the ratio of dihydroxyaryl compound to diary! car› bonate, of the loss rate of the diary! carbonate on the vapours, resulting from the choice of the procedure or plant for the preparation of the polycarbonate, and optionally of further compounds added, such as, for example, a higher-boiling monohydroxyaryl compound, the terminal groups are char› acterized in type and concentration. 

[0141] In the context of the invention, C$_{1}$-C$_{4}$ -alkyl, repre› sents, for example, methyl, ethyl, n-propyl, isopropyl, n-bu› tyl, sec-butyl, or tert-butyl; C$_{1 }$-Ccalkyl additionally repre- 

