Paperboard or cardboard

Abstract

A paperboard and a cardboard comprising at least one nonwoven web layer are provided. The nonwoven web layer comprises a plurality of first fibers, a plurality of second fibers, and a binder. The first fibers comprise a water non-dispersible synthetic polymer and have a different configuration and/or composition than the second fibers. The first fibers have a length of less than 25 millimeters and a minimum transverse dimension of less than 5 microns. The nonwoven web layer comprises at least 1 weight percent of the first fibers, at least 10 weight percent of the second fibers, and at least 1 weight percent of the binder. The paperboard and cardboard can incorporate a large amount of post consumer recycled fibers and still exhibit high strength and durability. Also disclosed is a process for producing the first fibers and the multicomponent fibers from which they are derived.

Description

RELATED APPLICATIONS[0001]This application claims priority from U.S. Provisional Application Ser. No. 61 / 405,308, filed on Oct. 21, 2010, the disclosure of which is incorporated herein by reference.BACKGROUND[0002]1. Field of the Invention[0003]The present invention relates to paperboards or cardboards and nonwoven fibrous webs for use as paperboards or cardboards.[0004]2. Description of the Related Art[0005]Paperboard and cardboard are thick paper-based materials used throughout the world that are produced using cellulosic fibers of various lengths. Paperboard and cardboard are generally utilized in packaging and heavy graphic printings due to their strength and durability, which is facilitated by their thickness and high basis weight. After their initial use, the paperboard and cardboard may be repulped to remove the cellulosic fibers, which can be recycled for further use.[0006]Although many new paperboards and cardboards initially exhibit high strength, recycled fibers derived f...

AI Technical Summary

Benefits of technology

[0008]In one embodiment of the present invention, there is provided an article comprising a paperboard or a cardboard. The paperboard or said cardboard can comprise at least one nonwoven web layer that contains a plurality of first fibers, a plurality of second fibers, and a binder. The first fibers comprise a water non-dispersible synthetic polymer and have a length of less than 25 millimeters and a minimum transverse dimension of less than 5. The first fibers can make up at least 1 weight percent and not more than 50 weight percent of the nonwoven web layer. Similarly, the second fibers make up at least 10 weight percent of the nonwoven web layer and the binder makes up at least 1 weight percent and not more than 40 weight percent of the nonwoven web layer. The nonwoven web layer has a tensile strength (TAPPI T494) of at least 0.1 kg / 15 mm and a basis weight (TAPPI 410) of at least 150 g / m2.

Problems solved by technology

Although many new paperboards and cardboards initially exhibit high strength, recycled fibers derived from paperboard and cardboard materials often lose strength when they are repulped.

This is especially evident in paperboards and cardboards that are made up of shorter cellulosic microfibers, such as those generally made in China, because repulping greatly deteriorates the lengths of these microfibers.

As a result, these recycled fibers are by themselves inadequate to produce a product with sufficient strength.

Unfortunately, these recycled paperboards or cardboards usually have a less predictable composition and poorer strength qualities when compared to paperboards and cardboards derived solely from virgin fibers.

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