Someone in the EtsyGreetings team found this recipe online:
ENVELOPE GLUE RECIPE
6 tablespoons white vinegar
(4) 0.1 oz. packets unflavored gelatin
1 tablespoon vanilla extract (or any flavor that you like)
- Bring vinegar to a boil in a small pan.
- Add gelatin and stir until dissolved.
- Add extract and stir until mixed.
- Brush on thin layer onto back of an envelope flap...Let dry.
- Moisten to apply.
Store excess glue in a sealed container and melt again for future use by putting in a pan of warm water.