This lesson is for anyone who advises a mill or a factory on how a new fabric order should be dyed: a buyer, a merchandiser, or a mill planner. Lessons 2.1 to 2.4 each taught one fact on its own: how dyeing works, which dye class fits which fibre, when a mill uses batch or continuous dyeing, and what happens when an order falls below a mill's dye-lot minimum. At work, nobody hands you these four facts separately. A new brief lands on your desk with a fibre and a quantity, and you must answer both questions together before you say anything useful to the mill. This lesson's decision, mainly a decision flow, is that combined method.
Without it, a real mistake follows: naming the right dye class but staying silent on order size, or checking order size but never confirming the fibre. Either half-answer leaves the mill, and the customer, unprepared for a cost or a delay that a complete answer would have caught.
You need: lessons 2.1 to 2.4 (how dyeing works, dye classes and fibres, batch vs continuous dyeing, dye-lot minimums). This lesson does not repeat their facts; it runs them together.
By the end of this lesson you can:
Not covered here: how dyeing itself bonds colour to fibre (lesson 2.1), the four dye classes in detail (lesson 2.2), batch vs continuous dyeing (lesson 2.3), and the two below-minimum options in detail (lesson 2.4).
| Term | Meaning |
|---|---|
| Dye class | A category of dye chemistry matched to a specific fibre type, such as reactive dye for cotton or vat dye for denim. |
| Fixation | The step that permanently bonds a dye to a fibre so the colour resists washing and rubbing off. |
| Reactive dye | The dye class formulated to bond with cellulosic fibres such as cotton; Order A's own fabric uses this class. |
| Disperse dye | The dye class formulated for synthetic fibres such as polyester. |
| Vat dye | A dye class, including indigo, that colours the outer surface of a fibre rather than all the way through; Order B's own denim uses this class. |
| Batch dyeing | Dyeing a fixed quantity of fabric together in one vessel, one dye lot at a time. |
| Continuous dyeing | Running fabric continuously through a dyeing line, suited to very large volumes. |
| Dye-lot minimum | The smallest quantity a mill will run as one dye batch; Colorline Dyeing's own minimum is 300 kg. |
This closing lesson adds no new fact. It assembles Course 2's four lessons into one method: run the dye class selector's fibre-type question and its order-size question on the same brief, then combine the two answers into one recommendation. The fibre-type question gives the dye class family (lesson 2.2). The order-size question, checked against Colorline Dyeing's 300 kg dye-lot minimum, gives the dyeing approach and flags any below-minimum options (lessons 2.3 and 2.4). Neither question alone is a complete answer for the mill.
A person who has learned all four lessons separately can still give an incomplete answer at work, because a real brief never labels its facts "fibre-type fact" and "order-size fact" the way a lesson does. The two facts arrive mixed together in a sentence or two, and it is the reader's job to pull them apart, answer both questions, and hand the mill one recommendation rather than two half-answers on two separate occasions.
| What can differ | The shapes you meet | Why it matters |
|---|---|---|
| Step 1, fibre type | Cotton, polyester, denim/indigo, or another fibre or blend named in the brief. | The fibre decides the dye class family; getting this wrong sends the whole recommendation to the wrong dye. |
| Step 2, order size | At or above Colorline Dyeing's 300 kg minimum, or below it. | Order size decides whether the order runs as its own dye lot at standard cost, or needs a below-minimum option (lesson 2.4). |
| Combining the two outputs | The tool's own formula reads both answers together and branches to one recommendation, rather than reporting the two questions separately. | A recommendation built from only one answer is not complete; the mill still needs the other half. |
| A two-fibre brief | A brief naming two different fibres in one order, for example a cotton main body with a polyester trim. | The method must be run once per fibre; running it once for the whole order risks applying one fibre's dye class to both. |
| Urgency changes the below-minimum choice | The same below-minimum order can call for the minimum-charge premium (fast, costs more) or for combining lots (slower, may cost less), depending on the customer's time pressure. | The tool's formula gives a default below-minimum path; a time-pressured brief still needs a person to weigh urgency against cost, as lesson 2.4 teaches. |
| A brief with no urgency stated | Some briefs simply give a fibre and a quantity, with no deadline mentioned at all. | Without a stated deadline, lesson 2.4's default (combining lots, since it can cost less) is the safer recommendation than assuming urgency that was never in the brief. |
Sara, the buyer at Northline Apparel, is handed a new customer's brief for a fabric order she must advise Colorline Dyeing on. The brief gives only two facts: the fibre is cotton, and the quantity is 150 kg, needed urgently. Sara must run the full two-question method before she tells the mill anything, rather than naming a dye class from the fibre alone and leaving the quantity for someone else to raise later.
The worked number150 kg is below the 300 kg minimum, so the order needs one of lesson 2.4's two below-minimum options. The brief says "needed urgently," so waiting to combine the order with another compatible cotton order is the slower, less certain path; paying the minimum-charge premium gets the smaller batch dyed now.
A common mistake is recommending a dye class without checking order size against the mill's minimum, or checking the minimum without confirming the fibre and its dye class. A correct dye class recommendation with no minimum-lot guidance leaves the buyer unprepared for a below-minimum cost or delay that only surfaces once the mill raises it later, by which point the customer's urgent deadline is closer and the choice is harder to make calmly.
This trap is easy to fall into precisely because each half looks complete on its own. "Use reactive dye" sounds like a finished answer, and so does "this order is below the minimum." Only when both halves sit together does the mill, and the customer, know what to expect: which chemistry will be used, and what the smaller-than-usual quantity will cost or delay. A method that always runs both questions together, as this lesson has shown, closes that gap before it reaches the mill.
This lesson does not teach a new fact. It shows how to use everything the last four lessons taught together, on one real brief. First find out what the fabric is made of; that tells you which dye to use. Then find out how much fabric is being ordered; that tells you whether the mill can run it as its own batch or whether it falls short of what the mill needs to make running a batch worthwhile. Never give an answer about only one of these two things. A buyer who names the right dye but forgets to check the quantity, or checks the quantity but forgets the dye, has only done half the job.
Facts:
The document Sara reads, exactly as it was handed to her:
Using the full method, what should Sara tell the mill? Decide before opening the answer.
Sara should tell the mill: use a reactive dye, because the fabric's fibre is cotton (lesson 2.2's fixed match for cellulosic fibres), and expect to pay the minimum-charge premium rather than wait to combine with another order, because the order's 150 kg is below Colorline Dyeing's 300 kg minimum and the brief marks it as urgent (lesson 2.4's urgency reasoning).
Two facts decide this together, not one. The fibre (cotton) decides the dye class; the quantity against the minimum (150 kg against 300 kg) decides the lot approach. Naming only the dye class would leave the mill and the customer unprepared for the below-minimum cost; naming only the lot approach would leave the fibre, and therefore the dye chemistry, unconfirmed.
Framed qualitatively, since this brief carries no fixed price: giving a dye-class recommendation without addressing the order-size question leaves a real cost or timeline risk unaddressed until the mill raises it, usually closer to the urgent deadline the brief already named. At that later point, the customer has less time to weigh the minimum-charge premium against waiting to combine lots, and may be forced into the more expensive choice by time pressure alone, rather than by an informed decision made when the brief first arrived. This is the real cost the combined two-step method is designed to prevent: not a fixed number, but a decision made too late to be a real choice.
Open `Dye class selector` (block above) and fill the Decide sheet's two rows for any new fabric brief: the fabric's main fibre, and whether the order meets Colorline Dyeing's 300 kg dye-lot minimum. The sheet's own formula combines both answers into one recommended dye class and lot approach, the same two-question method this lesson has walked through on Sara's brief.
| Question | Sara's brief (filled in) | Your brief |
|---|---|---|
| What is the fabric's main fibre? | Cotton | |
| Is the order at or above the 300 kg minimum? | No (150 kg) | |
| Recommended dye class and lot approach | Reactive dye; below minimum, pay the premium given urgency |
1. What are the two questions this course's dye class selector runs together?
2. For a brief reading '400 kg of polyester fabric, one colour, no urgency stated,' what should the dye class selector recommend?
3. Should a dye-class recommendation ever be given without checking the order-size question?
| EN | AR | FR | TR | Meaning |
|---|---|---|---|---|
| Dye class | فئة الصبغة | Classe de teinture | Boya sınıfı | A category of dye chemistry matched to a specific fibre type, such as reactive dye for cotton or vat dye for denim. |
| Fixation | التثبيت | Fixation | Sabitleme | The step that permanently bonds a dye to a fibre so the colour resists washing and rubbing off. |
| Reactive dye | صبغة فعالة | Teinture réactive | Reaktif boya | The dye class formulated to bond with cellulosic fibres such as cotton; Order A's own fabric uses this class. |
| Disperse dye | صبغة متشتتة | Teinture dispersée | Dispers boya | The dye class formulated for synthetic fibres such as polyester. |
| Vat dye | صبغة وعائية | Teinture de cuve | Küp boya | A dye class, including indigo, that colours the outer surface of a fibre rather than all the way through; Order B's own denim uses this class. |
| Batch dyeing | صباغة الدفعات | Teinture par lots | Kesikli boyama | Dyeing a fixed quantity of fabric together in one vessel, one dye lot at a time. |
| Continuous dyeing | الصباغة المستمرة | Teinture en continu | Sürekli boyama | Running fabric continuously through a dyeing line, suited to very large volumes. |
| Dye-lot minimum | الحد الأدنى لدفعة الصباغة | Minimum de lot de teinture | Boya partisi minimumu | The smallest quantity a mill will run as one dye batch; Colorline Dyeing's own minimum is 300 kg. |
You can now choose a dye class and dyeing method for a fibre and an order size. The next course moves one step further: once a dye class is chosen, how does a buyer set the exact colour a mill must match, and communicate it so the mill can dye toward it? Back to the course map