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[0762] With respect to the obtained copolymer (A2’-6), the weight average molecular weight (Mw) and the polydisper› sity (Mw/Mn) were determined by the polystyrene equiva› lent value as measured by gel permeation chromatography (GPC). As a result, it was found that the weight average molecular weight was 7,000, and the polydispersity was 1.6. The composition of the copolymer (ratio (molar ratio) of the respective structural units within the structural formula) as determined by $^{13}$C-NMR was l/m=50/50. 

[0763] With respect to each copolymer, the compositional ratio of the polymers (the molar ratio of the respective structural units in the polymeric compound) as determined by $^{13}$C-NMR, the weight average molecular weight (Mw) and the polydispersity (Mw/Mn) determined by the poly› styrene equivalent value as measured by GPC are also shown in Table 3. 

[0764] In Table 3, (al0l) indicates p-hydroxystyrene. By the deprotection reaction, the structural unit derived from p-ethoxyethoystyrene (EESt) is converted to a structural unit derived from p-hydroxystyrene (a structural unit formed by cleavage of the ethylenic double bond of p-hydroxystyrene ). 

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[0765] <Production of resist composition> 

## Examples 2 to 6, Comparative Examples 5 to 10 

[0766] The components shown in Table 4 were mixed together and dissolved to obtain each resist composition (solid content: 2.0 wt%). 

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[0767] In Table 4, the reference characters indicate the following. The values in brackets [ ] indicate the amount (in terms of parts by weight) of the component added. 

[0768] (A’)-1 to (A’)-5: The above copolymers (Al’-1-1) to (Al ’-1-5). 

[0769] (A’)-6 to (A’)-11: The above copolymers (A2’-1) to (A2’-6). 

[0770] (B)-2: An acid generator of the compound repre› sented by (B)-2 below 

[0771] (D)-1: acid diffusion control agent of a compound represented by chemical formula (D)-1 below 

[0772] (S)-2: a mixed solvent of propylene glycol monom› ethyl ether acetate/propylene glycol monomethyl ether=60/ 40 (weight ratio). 

[Chemical Formula 78] 

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