What is Lab dip? Lab dip Development Procedure and Lab dip Calculation. 

What is Lab dip?

A lab dip is a specimen or swatch of dyed fabric or yarn prepared for color approval and its recipe before bulk dyeing. It is also a masterpiece for both supplier and buyer. Before the bulk dyeing lap dip approval is essential from the buyer.

Fabric supplier company evaluates fabric color and shade visually with the help of a lightbox or digitally by spectrophotometer.

Define color standards/Panton book

It is important to know the dyeing color standard before bulk fabric dyeing, which must provide by the buyer as a reference sample or standard shade or dyed fabric swatch. Which is used as a frame for future production. This means that the customer and supplier will set an acceptable limit of the color variation.

Note that, the color look on the paper will be different from the fabric texture when using the Panton color swatch. The supplied swatch is better if it is large so that it is easy to develop the right shade. If the weight of the color standards swatch is less or high then the difference of shade can be seen.

Lab dip development procedure:

Lab dip development is a main lab work role in dyeing process. Bulk dyeing process is not possible without lab dip development. Lab dip development procedure is given below:

 a)   Receiving Lab dip requisition from the buyer.

 b)   Keeping record in computer or LDRL file.

 c)   Assessment of the shade for the recipe making by using spectrophotometer or shade reference.

 d)   Trial dyeing of the first recipe for first correction.

 e)   Trial dyeing of the first recipe for 2nd correction. 

 f)    Selection closest lap dip samples are sent to the buyer by shade grouping with A, B, C, D

 g)   If necessary, shade matching in a spectrophotometer or lightbox according to the buyer requirement, pass/fail report is sent with lap dip by mail.

 h)   After getting approval/comments from buyer by mail, if the shade is rejected, then redeveloping following buyer comments.

 i)     Approved by the buyer then order for bulk production.

Lab Dip Calculation: 

Usually, following calculations are followed:
 

1. Dye Solution = (Shade % * Sample Weight) / (Stock solution %)   (cc).

2. Salt = (Shade % * Liquor) / 1000 (gram per liter, gpl).

3. Soda Solution = (Shade % * 100 * Liquor) / (1000 * Stock solution %)    (cc).

Sample Calculation for 0.5% Shade:

·   Sample wt. = 6 mg

·   Material liquor ratio = 1: 10

·   Total liquor (6 *10) = 60 cc

·   Dye solution required = (6 * 0.5%) /1% =3 cc

·   Salt solution required = (60 * 25) / (20 * 10) = 7.50 cc

·   Soda ash solution required = (60 * 10) / (20 * 10) = 3 cc

·   Water required{60 – (3 + 7.50 + 3)} = 46.5 cc