Q. What is a common name for PVA adhesive, Sobo, or Elmer's Glue?

Technically speaking, both Sobo and Elmer’s are PVA-based glues. For bookbinding and repair, the quality of the glue is very important. Flexibility when dry and pH neutrality are both important for long-term preservation. In our conservation lab we use Jade 403, which is a pH-neutral PVA adhesive with a medium drying time and good flexibility. Jade is available from some art supply stores and bookbinding supply vendors.