Fire retardant nonwoven material and process for manufacture

A fire retardant, nonwoven material comprising a core, containing:

• (A) from about 30 weight percent to about 95 weight percent matrix fibers, the matrix fibers comprising individualized cellulosic fibers;
• (B) from about 60 weight percent to about 5 weight percent core binder, where weight percentages in the core are based on the total weight of the core;
• (C) a fire retardant, where the fire-retardant nonwoven material has a Burn Through Time in a fire barrier screening test of about 1 minute or greater;
• and where
• (D) the core has a basis weight of from about 200 g/m2 to about 3000 g/cm2,
• (E) the core has a density of from about 0.015 g/cc to about 0.10 glee, and
• (F) the nonwoven material has sound transmission reduction of 5 decibel or greater in an LSTT sound transmission test.

A fire retardant, nonwoven material, comprising:

• (a) a scrim with an interior surface and an outer surface, the scrim having a basis weight of from about 8 gsm to about 200 gsm;
• (b) a nonwoven material having an interior surface and an outer surface, wherein the interior surface of the nonwoven material is in contact with the interior surface of the scrim, the nonwoven material having a basis weight of from about 10 g/m2 to about 2000 g/m2 which contains from about 30 weight percent to about 95 weight percent matrix fibers, wherein the matrix fibers comprise individualized cellulosic fibers, and from about 5 weight percent to about 70 weight percent of a binder where the weight percentages are based on the total weight of the nonwoven material;
• and
• (c) the nonwoven material having been treated with a fire retardant.

A process for the production of a fire-retardant nonwoven material, comprising:

• (A) providing a comminution sheet of cellulosic fibers,
• (B) comminuting the sheet into individualized cellulosic fibers,
• (C) providing binder fibers,
• (D) air conveying the individualized cellulosic fibers and binder fibers to form a mixture of matrix fibers,
• (E) air laying the matrix fibers on a forming wire to form an airlaid nonwoven material,
• (F) optionally, depositing a latex binder on the airlaid nonwoven material,
• (G) heating the nonwoven material to cure the binder fibers,
• (H) depositing a fire retardant on the nonwoven material, and
• (I) optionally, depositing an anti-leachant on the nonwoven material.

A process for the production of a fire-retardant, nonwoven material comprising:

• (1a) on a moving foraminous wire from one or more forming heads, depositing a mixture comprising:
• (A) from about 95 weight percent to about 40 weight percent matrix fibers, wherein the matrix fibers comprise individualized cellulosic fibers,
• (B) from about 60 weight percent to about 5 weight percent core binder, to form a core of the nonwoven material, where weight percentages in the core are based on the total weight of the core, and
• (C) a fire retardant, followed by
• (2a) heating the nonwoven material to consolidate the mixture of matrix fibers and binder, or,
• (1b) deposition on a moving foraminous wire of
• (A) a woven or nonwoven carrier with a basis weight of from about 10 gsm to about 2000 gsm;
• followed by
• (2b) deposition on the carrier from one or more forming heads of a mixture containing
• (B) from about 95 weight percent to about 40 weight percent matrix fibers, wherein the matrix fibers comprise individualized cellulosic fibers,
• (C) a fire retardant, and
• (D) from about 60 weight percent to about 5 weight percent core binder,
• to form a core of the nonwoven material, where weight percentages in the core are based on the total weight of the core, and so that the carrier is integral with a surface of the core, followed by
• (3) heating the nonwoven material to consolidate the mixture of matrix fibers and binder, wherein
• (E) the core has a basis weight of from about 200 gsm to about 3000 gsm, and
• (F) the core has a density of from about 0.015 g/cc to about 0.10 g/cc.

A process for the production of a nonwoven structure, comprising;

• (1) providing a scrim with an interior surface and an outer surface, the scrim having a basis weight of from about 8 g/m2 to about 200 g/m2;
• (2) airlaying a nonwoven material on the interior surface of the scrim, the nonwoven material having a basis weight of from about 10 g/m2 to about 2000 g/m2 which contains from about 30 weight percent to about 95 weight percent matrix fibers, wherein the matrix fibers comprise individualized cellulosic fibers, and from about 5 weight percent to about 70 weight percent of a binder where the weight percentages are based on the total weight of the nonwoven material;
• (3) depositing on the outer surface of the scrim from about 1 g/m2 to about 40 g/m2 of a polymeric coating;
• (4) depositing a fire retardant material onto an outer surface of either the nonwoven structure or the scrim so that the nonwoven structure has a Burn Through Time in a fire barrier screening test of about 1 minute or greater;
• and, optionally,
• (5) depositing on the outer surface of the nonwoven material from about 1 g/m2 to about 40 g/m2 of a second polymeric coating.

A process for the production of a fire-retardant nonwoven material comprising:

• (A) depositing a fire retardant on a comminution sheet of cellulosic fibers,
• (B) comminuting the sheet into individualized cellulosic fibers,
• (C) providing binder fibers,
• (D) air conveying the individualized cellulosic fibers and binder fibers to form a mixture of matrix fibers,
• (E) air laying the matrix fibers on a forming wire to form an airlaid nonwoven material,
• (F) optionally, depositing a latex binder on the airlaid nonwoven material,
• (G) heating the nonwoven material to cure the binder, and
• (H) optionally, depositing an anti-leachant on the comminution sheet or on the nonwoven material.

A process for the production of a nonwoven material comprising:

• (A) providing a comminution sheet of cellulosic fibers,
• (B) treating the comminution sheet with a substance by spraying or dousing the comminution sheet;
• (C) comminuting the sheet into individualized cellulosic fibers,
• (C) providing binder fibers,
• (D) air conveying the individualized cellulosic fibers and binder fibers to form a mixture of matrix fibers,
• (E) air laying the matrix fibers on a forming wire to form an airlaid nonwoven material, and
• (F) heating the nonwoven material to cure the binder fibers.