Linen: A Step-by-Step Guide to Flax Processing and Textile Production

By Eman Abdallah Kamel

Linen fibres are durable, soft, and luxurious to the touch. This article introduces flax and linen and outlines the step-by-step manufacturing process.

Introduction

Flax (Linum usitatissimum), also known as linseed, is an ancient annual crop cultivated since approximately 30000 BC for its seeds and fiber. Its stem fibers are widely utilised in textile production, while various plant-derived by-products are used in the manufacture of medicines, gels, soaps, fishnets, paper, and dyes. Flaxseeds are also processed to produce linseed oil and are recognised as a rich source of omega fatty acids, which are associated with various health benefits.

Flax is mainly cultivated in temperate and cool regions worldwide. It has a thin, upright stem that grows to about three feet, delicate blue flowers lasting about one day, and small, flat, oval seeds with important nutritional and industrial uses. To learn more about flax cultivation, visit Growing Flax At Home

Linen is a natural fabric made from flax stem fibers. After several processing stages, it is used for clothing, tablecloths, and bed sheets. It is soft, flexible, and lustrous. High-quality flax produces apparel, while lower-quality linen is used for ropes. Historically, linen was a major fabric before wool and cotton became widespread, with ancient Egyptians using it extensively. Let’s learn more about linen production steps.

Flowchart of the linen production process.

Linen Production Stages

1. Retting

Retting is the first stage in converting flax into fiber.

After harvesting, farmers spread the flax stalks in rows in the field, each row about a meter long, and leave them to decompose because of enzymes in the soil.
Rain and other local weather conditions accelerate this process.
To prevent mold, the stalks must be packed tightly but not too tightly. Farmers rotate the stalks to ensure even distribution and improve retting. The efficiency of the retting process greatly affects fiber quality.
During this process, the pectins that bind the fibers to the woody part of the plant break down. This step can take from two to twelve weeks, depending on climatic conditions and the industrial requirements for the fiber. At the end of the retting process, when the flax stalks are completely dry (less than 15% moisture), they are stored wrapped in round or rectangular bales.

Did You Know?

After collecting the retted stems, experts assume no significant biomass remains in the field. Dust and small shives are negligible, so the mass loss is considered emissions to air.

2. Scutching

The retted stems are pressed and transported to scutching facilities, where the woody part of the stalk is broken off to facilitate access to the fibers. This is the first stage of mechanical fiber conversion, a process that yields several byproducts, including:

Long fibers, ranging from 60 to 90 cm in length.
Short fibers, less than 60 cm in length.
Grains, flakes, and plant residues that may contain some dust and soil.

Bales are unrolled, seeds are removed by beating, and flax stems are aligned and passed through toothed rollers that crush, beat, and comb them to remove the woody core. Drum carders separate and clean long and short fibers at about 200 rpm. Long fibers are retained, while co-products and plant residues are removed, with dust extracted by aspiration.

What are short fibers used for?

Short fibers (scutched tow) are mainly used as reinforcement in thermoplastic composites for:

Leisure products (rackets, skis, helmets, boards).
Automotive parts (dashboards, door panels).
Eco-building and furniture.
Low-quality short fibers can be used as housing insulation material.

3. Hackling

Hackling separates long-line fibers from shorter tow using a bed of pins or nails. The flax is held at one end and combed through the hackle to remove the fibrous core, clean the fibers, and make them shiny, parallel, and uniform in length. The fibers left in the hackle teeth can be removed, recombed, and reused.

4. Drawing

Drawing blends, doubles, and levels slivers. Operations performed on the drawing machine:

Drafting: Increasing the length per unit weight of sliver by roller speed.
Doubling: Combining 2 or more slivers into one. Usually, 6 slivers → 1 sliver.

5. Combing

Long fibers are combed to untangle, homogenize, and remove debris, then formed into flax slivers ready for spinning. This process produces flax tow and plant residues, which are generally returned to nearby fields as soil amendments. The comber must do the following to enhance yarn quality:

Remove a controlled amount of short fibers.
Remove remaining impurities.
Remove most neps.
Produce an even sliver.
Straighten and parallelise the fibers.

6. Roving

The main purpose of the roving frame is outlined as follows:

Drafting: In a roving frame, two drafting systems are commonly used. In a 4-over-4 drafting system, the total draft should be approximately 13, whereas in a 3-over-3 drafting system, the total draft should not exceed 11.
Twisting is a crucial factor in generating strength within the fiber strand (roving). The flyer performs this twisting process; its rotation imparts twist to the fiber strand (sliver), and the degree of twist depends on both flyer speed and feed speed.
Winding uses builder motion. Its main function is to shift the cone belt as the bobbin diameter increases and to reverse the bobbin rail movement at the upper and lower ends of the lift stroke.

7. Bleaching

Flax is bleached as yarn to remove impurities such as waxes, fatty acids, pectins, and pigments.

Flax yarn bleaching is a simple process involving three main steps: boiling with alkali, bleaching with suitable agents, and souring with dilute sulphuric acid (H₂SO₄) or hydrochloric acid (HCl).

8. Spinning

Next, the flax slivers are spun by untangling, aligning, and stretching the fibers to form yarn. There are two ways of spinning:

Dry Spinning: In this method, a volatile solvent dissolves the raw materials to form a solution, which is then purified by filtration. The solution is then extruded through a spinneret into a warm-air chamber, where the solvent evaporates and the fine filaments solidify. The filament yarn is either wound directly onto bobbins or further treated for specific characteristics or end use.
Wet Spinning: In this process, a non-volatile solvent converts the raw material into a solution. This solution is forced through a spinneret, where the solvent is removed either by simple washing or through a chemical reaction between the polymer solution and a reagent present in the spinning bath. Following extrusion, the solvent is removed in a liquid coagulation medium. The filaments are then wound directly onto bobbins or undergo further processing to acquire specific required properties or to suit a particular end-use.

9. Winding

After yarn manufacturing, winding converts ring bobbins into final cones ready for shipment. The main objectives are:

Fault removal: Electric scanners (Uster) detect and remove yarn faults, called scan-cuts
Splicing: Broken yarns are joined to eliminate knots and poor piecing.
Package conversion: Small ring bobbins are converted into larger cones according to international standards or customer requirements.

Winding faults must be continuously monitored and controlled, as they can cause yarn breakage during subsequent processes such as warping, knitting, or doubling and lead to customer complaints.

10. Weaving

During this process, starch is typically used as an adhesive. The result is a technical linen fabric weighing 360 g/m².

FAQs

What is the difference between flax and linen?

Flax is a plant, while linen is a fabric made from fibers extracted from its stem. Flax fibers produce linen, a durable and historically prestigious fabric. Linen is one of many flax by-products, along with paper, dyes, fishnets, medicines, soap, and hair gels. Linen is naturally tan-coloured and is usually bleached white before being dyed into other colours.

What are the stages of linen manufacturing?

The stages of linen manufacturing are retting, scutching, hackling, drawing, spinning, bleaching, roving, combing, winding, and weaving.

What does the ‘hackling’ process mean?

Hackling uses a bed of pins or nails to separate long-line fibers from shorter tow.

Sources

About the author: Eman is a textile engineer and writer. She holds a bachelor’s degree in textile science from Egypt’s Faculty of Applied Arts.

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