Modulor bone glue is a brittle glutine glue for bonding wood, cardboard or paperboard (bookbinding adhesive). It can also be used in painting work (primer for rigid painting surfaces), as a paint binder (distemper technique) or for making modelling compounds. Bone glue is a natural product that will maintain its effectiveness for practically an unlimited amount of time as long as it is stored in a cool and dry place.
When preparing it for a typical gluing job, the granulate should be stirred into cold water (maximum: room temperature) in a ratio of 1:4. After allowing it to soak for 2 to 6 hours, the resulting mixture should then be stirred again in a water bath at a temperature of 50°C (maximum 60°C – definitely do not allow the water to boil because the glue will lose its bonding strength). At this temperature the beads will dissolve into a solution. The glue should be warm when being used because if the temperature of the admix falls below 50°C, the solution will begin to form a gel.
Collagen (glue-like proteins) is converted into gluten by means of cooking animal offal (the glue making bodies, e.g. skin, bones, cartilage). The substance that is formed after drying is a natural glue that can then be dissolved again in water. The product name derives from the component, gluten. The different types of glutine glue are delineated by their sources, as in bone glue, hide glue, rabbit-skin glue, isinglass, etc.
Collagen was used by the ancient Egyptians as a glue for wood, etc. and Plinius mentioned it as a binder for paints. Glutine glues are still used today, especially in restoration work on furniture, musical instruments, and old books or as a primer on flexible painting surfaces (e.g. painting canvases).
To use this glue, the dried glue beads must be soaked in water for a number of hours. The resulting swollen glue beads should then be stirred into a 50 - 65° C water bath and applied (multiple times) with a brush or sponge. Please note that the processing time is fairly short (when removed from the water bath, the glue will quickly cool and gel you can, however, reheat the glue again for further use).
The degree of adhesive strength of glutine glue is very high while at the same time it can always be reversed, which means that it can be removed by means of applying heat and moisture as required. The attributes of joints made with glutine glue range from hard to elastic. They are not, it should be noted, moisture or heat resistant and are sensitive to bacteria and mould. Because of this, glutine glue should only be used in dry indoor areas. When stored in a dry and cool place, it has an almost unlimited shelf life.