Binder composition based on plant fibers and mineral fillers, preparation and use thereof

A method for preparing a composition a binder composition containing water, plant fibers and mineral fillers,

• wherein the method comprises the following steps:
• preparing a suspension of plant fibers and mineral fillers in water, the weight ratio between the plant fibers and the mineral fillers being comprised between 99/1 and 2/98,
• refining this suspension,
• obtaining a binder composition wherein the refined fibers have a mean size of between 10 and 700 μm, and wherein the refined fibers, at least partially, embed the refined mineral fillers,
• wherein fibers are enzymatically treated before refining the suspension,
• wherein, refining is carried out between parallel discs, and stopped after 10 to 80 passes between parallel discs.

A method for preparing a composition a binder composition containing water, plant fibers and mineral fillers,

• wherein the method comprises the following steps:
• preparing a suspension of plant fibers and mineral fillers in water, the weight ratio between the plant fibers and the mineral fillers being comprised between 99/1 and 2/98,
• refining this suspension,
• obtaining a binder composition wherein the refined fibers have a mean size of between 10 and 700 μm, and wherein the refined fibers, at least partially, embed the refined mineral fillers,
• wherein fibers are enzymatically treated before refining the suspension,
• wherein, refining is carried out between parallel refiner discs, in the absence of any grinding medium made of ceramic or metal,
• wherein, after the refining step, water is partially evaporated to concentrate the binder composition.