Cold Pad Batch

Definition and Overview

Cold pad batch is a dyeing method in which fabric is immersed in dye liquor, then padded to remove excess liquid, after which it is stored in a rolled state for a set period to let the dye react with and fix to the fibers. It is generally used for cotton, rayon, and other materials dyed with reactive dyes.

The word cold comes from the fact that, compared with methods that continuously fix dye at high temperatures, it mainly uses reaction time at around room temperature in batches, meaning by rolled units of fabric. It is a term that refers to the post-dyeing process, not the fabric structure itself.

Features

Because dyeing is carried out while suppressing high-temperature treatment, depending on the combination of material, pretreatment, dye, and after-finishing, it is said to be easier to make use of the natural softness and texture of cotton. However, the hand feel also changes greatly depending on the raw material, woven or knitted structure, scouring and bleaching, and finishing.

Temperature, humidity, rolled condition, and the amount of dye liquor adhered during the reaction time affect the color tone. For this reason, to reduce uneven color and lot-to-lot color differences, it is important to control process conditions and confirm with trial dyeing.

• The appearance is basically solid dyed, but the color design from light to dark varies depending on the dye and formulation.
• The dyeing method alone does not determine functions such as absorbency, quick-drying performance, or stretchability.

Main Applications

It is used for woven fabrics and knits mainly made of cotton and rayon, and is made into shirts, blouses, cut-and-sew tops, dresses, skirts, pants, and more. It is also suitable for casual wear that emphasizes a rustic, soft feel, and for lightweight clothing for spring and summer.

However, applications are not determined by the dyeing method alone; fabric thickness, density, stretch, sheerness, and the required color fastness must also be considered. Even with the same cold pad batch dyeing, suitable items and seasons differ depending on the material and finish.

Selection and Handling Precautions

When placing an order, confirm the blend ratio, type of dye, test items and standards for color fastness, shrinkage rate, and finished width. In particular, evaluate in advance the risk of color transfer from rubbing for dark colors and discoloration from washing or perspiration for light colors, according to the intended use.

Before cutting and sewing, check shrinkage and skew under the same washing conditions as actual production, and if necessary carry out a water pre-wash or relaxation. Because friction in a wet state and partial wetting can appear as causes of uneven color, pay attention to moisture and dirt during sewing as well.

Wash according to the product care label. For the initial wash, wash separately and avoid long soaking or leaving the item wet, as this makes it easier to reduce the risk of color transfer to other garments and color change.

Differences from Similar Terms

Piece dyeing refers broadly to methods of dyeing woven or knitted fabric after it has been made. Cold pad batch is a specific dyeing method included within piece dyeing, and its process order differs from yarn dyed methods, which dye at the yarn stage.

Continuous dyeing broadly refers to production methods that process fabric continuously. Cold pad batch also allows the padding step to be done continuously, but its distinctive feature is that fixation uses a storage period after rolling.

Frequently Asked Questions