content_image/927414.jpg content_image/927416.jpg content_image/927417.jpg content_image/927418.jpg
<img src='content_image/927414.jpg'>

Herein RL 41 is as defined above. 

Illustrative examples of the acid labile group of formula (L4) are given below, but not limited thereto. 

<img src='content_image/927416.jpg'>

Examples of the C$_{4}$ -C$_{20 }$tertiary alkyl groups, trialkylsilyl groups in which each alkyl moiety has 1 to 6 carbon atoms, and C$_{4}$ -C$_{20 }$ oxoalkyl groups, represented by XA, are as exemplified for RL 04 . 

Illustrative examples of the recurring units of formula (6) are given below, but not limited thereto. Herein R 1 1s as defined above. 

<img src='content_image/927417.jpg'>

-continued 

(IA-4-endo) 

<img src='content_image/927418.jpg'>

-continued 

