Possible Clues:

• School supplies brand with a cow logo
• Art class staple with a bovine logo
• *Triage site's gooey alternative to sutures?
• E-bond?
• Scrapbooking staple
• Collagist's need (and a hint to what is 'stuck' to the beginnings of 17-, 30-, and 48-Across)
• Big sticker?
• Kids' art class staple