Bonding patterns for construction of a knitted fabric landing zone

Abstract

A knitted fabric female fastening portion for a mechanical fastener having a knitted fabric, an underlying substrate, a bonding layer, said bonding layer having a first plurality of non-intersecting bond lines and a second plurality of non-intersecting bond lines which are combined to form a pattern of intersecting bond lines that define tessellating pattern elements. Said pattern of intersecting bond lines may have a CD percent coverage standard deviation not equal to 0% and an MD percent coverage standard deviation not equal to 0%.

Description

FIELD OF THE INVENTION [0001] The present invention relates to bonding patterns for construction of knitted fabric fastener female portions. More particularly, bonding patterns for construction of knitted fabric landing zones for a disposable absorbent article. BACKGROUND [0002] Refastenable mechanical fastening systems are used in a wide number of consumer product applications. Such fastening systems are used to connect one portion of an article to another portion of the same article, or another article, or device. Typically, refastenable mechanical fastening systems comprise a receiving (or female) member and an engaging (or male) member. The receiving member generally comprises a plurality of fibrous engaging elements (e.g., loops). The engaging member generally comprises a plurality of hook elements. The hooks are capable of entangling with the loops to form a connection between the engaging and receiving members. [0003] One particular type of receiving member is a knitted fabri...

AI Technical Summary

Benefits of technology

[0017] While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter that is regarded as the present invention, it is believed that the invention will be more fully understood from the following description taken in conjunction with the accompanying drawings. None of the drawings are necessar

Problems solved by technology

When designing a suitable refastenable mechanical fastening system, particularly one having a knitted fabric landing zone, the competing interests of the Peel Test and CD Bond Strength Test make it difficult to construct the optimal fastening system.

More specifically, the addition of more adhesive between the fabric base structure and the underlying substrate should increase the CD Bond Strength value; however, said adhesive will frequently migrate through said base structure and to the loops on the opposing side, and in doing so, said loops will no longer be free for subsequent fastening to the hooks.

While this process is designed to provide adhesive in the areas in which it's needed (i.e., chains) and not in the areas in which it's undesirable (i.e., loops), this process typically involves the risk of potentially gluing down portions of the loops within the area of the chains where most of the adhesive is present, especially if mis-tracking of the adhesive occurs.

Additionally, such an approach involves the added process complexity and costs associated with a targeted but random (due to variations) glue deposition on the fabric base structure (i.e., on the chains of the knitted fabric).

However, this approach requires the use of specially designed fabric patterns and thus reduces the degrees of freedom in fabric selection.

In so doing, however, an undesirable amount of adhesive will still migrate through the base structure and to the loops on the opposing side.

Such a 100% coverage pattern should result in a high CD Bond Test value; however, said application pattern should also result in a low Peel Test value because many of the loops have been contaminated with adhesive.

Such a random pattern should result in a medium value for both the CD Bond Test and the Peel Test; however, the inherent randomness of the pattern sometimes results in a variable connection performance.

Yet another prior art pattern involves a bonding pattern having CD and MD bond lines, however, such prior art is directed to the bonding of a nonwoven to an underlying substrate which does not involve nor address the unique issues of knitted fabric (e.g., it is desirable to place adhesive on the chains but not on the loops of the knitted fabric and to prevent the presence of frayed edges).

When applying this additional consideration to the prior art examples discussed above, it is further appreciated that the task of optimizing the adhesive application pattern is even more difficult.

For example, a 100% coverage pattern does in fact provide the most optimal perimeter coverage; however, said pattern may have a low Peel Test value.

In another example, the striped pattern will have gaps along the perimeter which correspond to the spacing of the stripes; such that, as the spacing is increased to improve the Peel Test value, the gaps along the perimeter will negatively increase.

In yet another example, the random pattern inherently will not provide predictable gap sizes and locations along the perimeter.

Consequently, none of the cited prior art examples properly address this perimeter adhesion consideration.

Consequently, the adhesive print pattern must be sufficiently robust enough to be cut in both the machine and cross directions without resulting in unduly large gaps along its perimeter; otherwise, frayed edges may appear and / or structural integrity may fail.

For example, in the prior art it is known that to overcome the negative effects of adhesive migrating to the loops, one skilled in the art may increase the basis weight of the knitted fabric.

However, a higher basis weight material is often cost prohibited, especially in the marketplace of absorbent articles.

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