A method is provided for preparing a film of crosslinked microfibrillated cellulose. Phosphorylated microfibrillated cellulose is cast or wet-laid into a film; and then said film is post-treated (e.g. by heat-treatment) to provide crosslinking between the phosphorylated microfibrillated cellulose. Films and hygiene products comprising such films are also described.

Disclosed are fibers comprising identification fibers which can be used for tracking and tracing fibers, yarns, fiber bands, and/or articles comprising the fibers through at least part of the supply chain. Each identification fiber exhibits at least one distinct feature. Each group of distinguishable identification fibers can exhibit a taggant cross-section shape, a taggant cross-section size, or combination of the same taggant cross-section shape and same taggant cross-section size. The distinct features and the number of fibers in each group of distinguishable identification fibers can represent at least one supply chain component of the fibers. The distinct features can be detectable in an article comprising the fibers.

The problem to be solved by the present invention is to prevent interruption of a cellulose acetate fiber during spinning of the cellulose acetate fiber thereby enhancing production efficiency of a cellulose acetate band. The cellulose acetate band according to an embodiment of the present invention is formed from cellulose acetate fibers, a total denier thereof is set to a value in a range from 8000 to 44000, a content of titanium oxide is set to a value in a range from 0 wt. % to 0.01 wt. %, and a content of a lubricant in the band measured by a diethyl ether extraction method is set to a value in a range greater than 5 mg but 65 mg or less per 1 m.

The problem to be solved by the present invention is to prevent interruption of a cellulose acetate fiber during spinning of the cellulose acetate fiber thereby enhancing production efficiency of a cellulose acetate band. The cellulose acetate band according to an embodiment of the present invention is formed from cellulose acetate fibers, a total denier thereof is set to a value in a range from 8000 to 44000, a content of titanium oxide is set to a value in a range from 0 wt. % to 0.01 wt. %, and a content of a lubricant in the band measured by a diethyl ether extraction method is set to a value in a range greater than 5 mg but 65 mg or less per 1 m.

Disclosed are fibers which contain identification fibers. The identification fibers can contain a one or more of chemical markers and one or more distinct features, or taggants, which may vary among the fibers or be incorporated throughout all of the fibers. The chemical markers and distinct features can be representative of specific supply chain information. The supply chain information can be used to track the fibers from manufacturing through intermediaries, conversion to final product, and/or the consumer. The disclosed embodiments also relate to the method for making and characterizing the fibers. Characterization of the fibers can include identifying chemical markers and distinct features and correlating the chemical markers and distinct features to manufacturer-specific taggants to determine supply chain information.

An object is to mitigate plugging of spinneret hole, the plugging occurring with the passage of spinning time, even though cellulose acetate has a small titanium dioxide content or contains no titanium dioxide, and to prevent a reduction in pressure drop of the resulting cellulose acetate band. A cellulose acetate fiber having a titanium dioxide content of not greater than 0.05 wt. %; and a content of at least one type of metal oxide selected from the group consisting of Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, MnO.sub.2, Cr.sub.2O.sub.3, Cr.sub.2CuO.sub.4, NiO, Sb.sub.2O.sub.3, and CoAl.sub.2O.sub.4 of not smaller than 0.05 wt. % and not greater than 1 wt. %.

An object is to mitigate plugging of spinneret hole, the plugging occurring with the passage of spinning time, even though cellulose acetate has a small titanium dioxide content or contains no titanium dioxide, and to prevent a reduction in pressure drop of the resulting cellulose acetate band. A cellulose acetate fiber having a titanium dioxide content of not greater than 0.05 wt. %; and a content of at least one type of metal oxide selected from the group consisting of Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, MnO.sub.2, Cr.sub.2O.sub.3, Cr.sub.2CuO.sub.4, NiO, Sb.sub.2O.sub.3, and CoAl.sub.2O.sub.4 of not smaller than 0.05 wt. % and not greater than 1 wt. %.

Disclosed are cellulose acetate cellulose acetate tow and processes for making cellulose acetate tow having at least 15 denier per filament, e.g., at least 20 denier per filament, or at least 25 denier per filament. The cellulose acetate tows may have total denier of more than 20,500.

Described herein are apparatuses and methods of creating fibers, such as microfibers and nanofibers, that are composed of saccharides. The methods discussed herein employ centrifugal forces to transform saccharide material into fibers. Apparatuses that may be used to create saccharide fibers are also described. Fiber producing devices with features that enhance fiber production and adaptability to different types of fiber are described.

Described herein are apparatuses and methods of creating fibers, such as microfibers and nanofibers, that are composed of saccharides. The methods discussed herein employ centrifugal forces to transform saccharide material into fibers. Apparatuses that may be used to create saccharide fibers are also described. Fiber producing devices with features that enhance fiber production and adaptability to different types of fiber are described.