Method of manufacture of a felted fibrous product from a nonaqueous medium

In a method for manufacturing a finished felted fibrous product from fibers, of which at least some of said fibers are cellulosic, said method including the steps of preparing a dry pulped mass from said fibers, forming bonds between said fibers, dry forming an intermediate felted fibrous product, and finishing said intermediate filed fibrous product to provide a finished felted fibrous product, an improvement consisting of the steps of:

• dispersing said fibers including said cellulosic fibers in an air suspension at least immediately prior to said step of dry forming said intermediate felted fibrous product to steam and a gaseous and ionized substance having a radical which includes a nitrogen atom and at least two hydrogen atoms for a predetermined time to hydrate said cellulosic fibers for later formation of hydrogen bonds at interfibrile contact points;
• and
• dry forming said intermediate product while said cellulosic fibers are hydrated,
• whereby said finished felted fibrous product is manufactured with a minimum of water and therefore a minimal amount of drying to form a final integral mass which is bound, at least in part, by said hydrogen bonds at said interfibrile contact points.

An improvement in a method for manufacturing felted fibrous product, said method comprising the steps of reducing a plurality of types of base materials into fibrous form, at least one of said types of base materials being cellulosic, preparing said cellulosic type of base material in fibrous form to form bonds between fibers of said cellulosic type of base material, mixing said plurality of types of base materials to form a blended fibrous mass, said improvement consisting of the steps of:

• dispersing said cellulosic types of base material when in fibrile form in an air suspension;
• injecting a substance in gaseous phase including a radical which in turn includes a nitrogen atom and at least two hydrogen atoms at a predetermined temperature and pressure for a predetermined time;
• ionizing said substance by said steam injection while said substance is in gaseous phase;
• hydrating said cellulosic type of base material with said substance and steam while aid material is dispersed in said air suspension;
• dry forming a fibrous mat form said blended fibrous mass from said plurality of types of base materials while said cellulosic type of base material is hydrated;
• and
• consolidating said fibrous mat to form a pressed sheet of said plurality of types of materials,
• whereby said cellulosic type of base material exposed to said substance is induced to form hydrogen bonds at interfibrile contact points between said cellulosic fibers, thereby forming an integral fibrous mass with a minimum of water and drying.

An improvement in a method for manufacturing a felted fibrous product, said method comprising the steps of reducing cellulosic material into fibers and air laying said fibers to form a fibrous mat defining interfibrile contact points among said fibers, said improvement consisting of the steps of:

• suspending said fibers in an air suspension;
• disposing a substance in said air suspension containing a radical, which includes a nitrogen atom and at least two hydrogen atoms;
• introducing said substance in gaseous phase in said air suspension;
• ionizing said substance while in gaseous phase in said air suspension;
• hydrating said fibers with said ionized vapor substance and steam while in said air suspension whereby hydroxyl groups on said cellulosic fibers are activated;
• and
• air laying said activated fibers to form a felted product while said fibers are hydrated,
• whereby hydrogen bonds are formed at said interfibrile contact points and said fibrous mat produced thereby being adaptable for further processing to form said felted fibrous product.