Textile Structure
how cloth is put together
Concept

Percolation — where it appears

The point at which a random assembly first has a connected path across it, which is what makes a nonwoven a fabric. It is a threshold in a probability rather than a criterion on a matrix, so a nonwoven's coherence is a different kind of statement from a weave's.

Named by 3 essays across 3 fields — each of them below, with the objects they name alongside it.

A web at 6 fibre lengths squared per unit area. Straight fibres dropped at random positions and random angles. The largest connected group is drawn solid; everything not joined to it is drawn faintly. Whether that group reaches both edges is what decides whether this is a sheet or a heap.

Nonwovens, and what holds them together instead

A web of fibres laid down at random has no repeat, so the exact test for whether a fabric holds together has nothing to work on. What replaces it is a threshold, and the threshold is sharp.

cloth · Integrity A filter cloth has two jobs. Opening size against sett for a woven filter cloth, with the two limits that specify one: the soil is retained below the retention line, and the water passes above the open-area floor. They pull opposite ways, so the answer is an interval in the sett — and for a fine enough soil there is no interval at all.

A filter cloth has two jobs

Hold the soil back and pass the water. The first wants a close sett and the second wants an open one, so a filter cloth is not a fabric but an interval — one that is sometimes a single sett wide, and for a fine enough soil is empty. The empty case is the useful one, because it says the answer is not a woven cloth at all.

applied · Openings Milling, on the nonwoven's own scale. Migrated fibre accumulating with agitation, measured against the stick-percolation threshold this site uses for nonwovens. Above the line the fibre network holds on its own, which is why a milled cloth can be cut without fraying — the weave is no longer the only thing keeping it together.

Milling holds the cloth a second time

This site's integrity criterion returns exactly the same answer for a melton as for the loose twill it was woven as, and it is right both times. What has changed is that a second network now holds the fabric together, made of migrated fibre rather than of thread crossings — and it is the one that decides whether a cut edge frays.

finishing · Felting

Named alongside it

The objects these essays reach for when they reach for this one.

NonwovenThresholdCloth integrityCoverFeltingFibre migrationFibre networkFrayingIntegrityOpening sizeRetentionSett

All concepts