On Shabbat, Is it permissible to place book page markers which are small plastic pieces with mild adhesive tape on the back which are used to place by important information when reading, so as not to forget about minor detail that I read about. Self-stick notes adhere securely and remove cleanly. They are like post it notes but they are made out of plastic and are Not made to write on If yes, can they remain permanently or do I have to take them off after shabbat. For clarification, this is what I am talking about: http://www.amazon.com/Post--Assorted-Colors-Arrows-683-VAD1/dp/B000MK4RAM/ref=sr_1_1?s=office-products&ie=UTF8&qid=1384473954&sr=1-1 http://www.officedepot.com/a/products/452409/Post-it-Flags-1-x-1/
The issue at hand is the adhesive on the back not so much if made out of plastic or paper. The question is if placing the paper on the book constitutes the "melacha" of "tofer" which is not just sewing but also gluing or sticking two things together. (See Biur Halacha on Shulchan Aruch 340). However, there is another issue of removing it from its original pad on Shabbat does the separating of the page from the pad constitute tearing? On the first issue of placing it in the book as a temporary marker, in the new edition of Shmirat Shabbat K’Hilchata, (chap. 28:8) he rules that they may be placed for a short time. While as far as the removing it from the pad, he stipulates that these notes or flags should be removed from the pad before Shabbat. However there are Poskim who are lenient and allow these self- adhesive bookmarks to be removed from the pad and to be placed in the book on Shabbat.(See Nishmat Shabbat vol. 7. Pg. 206 and in regard to removal see Tzitz Eliezer 16: 6, Yechaveh Daat 6:24, also Shmirat Shabbat K’Hilchata old edition chap. 35 note 66, and new edition chap. 9 note 21, see also Peninei Halacha, Rav Eliezer Melamed, vol. 1, pg. 292-293) Happy Chanuka!!