Ziploc vs ziptop

Ziploc

noun
  • Any of a range of disposable, resealable storage bags that are fastened by a pair of interlocking plastic flanges. 

ziptop

adj
  • Fastened by a zipper at the top. 

How often have the words Ziploc and ziptop occurred in a corpus of books? (source: Google Ngram Viewer )