UPMSP Vocational Laundry & Dyeing cheat sheet

Four laundry factors act together: mechanical action, temperature, chemical action and time; increasing one allows reducing another to protect the fabric.

Sinner's circle: for a fixed cleaning result, the four factors are interchangeable within limits; delicate fibres need low mechanical action compensated by longer time or milder chemistry.

Soil types: water-soluble (sugars, salts), oily/greasy (sebum, cooking oil), particulate (clay, soot), proteinaceous (blood, egg, milk) and bleachable (tea, wine, fruit).

Protein stains coagulate above roughly 40 °C, so blood and egg must be washed cool before any hot treatment.

Dyeing is a mass-transfer process: dye moves from the bath to the fibre surface, then diffuses into the fibre; levelness depends on slow, uniform exhaustion.

Fibre moisture regain determines comfort and ironing behaviour: cotton about 8.5 %, viscose about 11-13 %, wool about 16 %, polyester about 0.4 %.

Alkalis swell cotton and increase dye uptake but damage wool and silk; acids are tolerated by protein fibres and attack cotton.

Water hardness is expressed as mg/L CaCO3; 0-60 soft, 60-120 moderately soft, 120-180 hard, above 180 very hard.

Burning test: cotton burns fast with a paper smell and grey ash; wool/silk self-extinguish with a burnt-hair smell and crushable black bead; polyester melts and shrinks with a sweet chemical smell and hard bead.

Solubility test: cotton dissolves in 70 % sulphuric acid; wool dissolves in 5 % sodium hypochlorite; polyester is resistant to most cold acids and alkalis.

Microscopy: cotton is a flattened twisted ribbon; wool shows overlapping scales; silk is smooth and triangular; viscose shows longitudinal striations; synthetics are smooth rods.

Plain weave: maximum interlacing, strong and firm, least drape. Twill weave: diagonal lines, better drape and soil hiding. Satin: long floats, high lustre, low abrasion resistance.

Knitted fabrics stretch because loops can re-form; woven fabrics are stable on the grain but fray at cut edges.

Regenerated fibres (viscose, modal, lyocell) lose strength when wet - about 40-50 % for viscose - so they must not be rubbed or wrung hard.

Blend identification requires more than one test: a polyester-cotton blend leaves a hard bead plus paper ash and burns with mixed odour.

Natural fibres are hydrophilic with polar groups; synthetic fibres are hydrophobic, so they attract oily soil more and release it less easily in water.

Spotting rule: work from the back of the fabric over an absorbent pad, from the outside of the stain inward, to avoid rings.

Always test an unseen area with the spotting agent for colour bleed and fibre damage before treating the visible stain.

Protein stains (blood, milk, egg, grass): cool water and enzyme detergent; never hot water or alkaline agents first.

Tannin stains (tea, coffee, wine, fruit): hot water plus a mild acid such as dilute acetic acid or a tannin remover.

Oil and grease: solvent-based agents or absorbent powder first; add water only after the solvent has been flushed out.

Rust: oxalic acid or a proprietary rust remover, followed by thorough rinsing; never chlorine bleach, which fixes rust.

Ink: alcohol or amyl acetate for ballpoint, water-based remover for fountain pen; test first because some inks contain dyes that bleed.

Chlorine bleach on wool or silk causes yellowing and fibre loss; oxygen bleach (perborate/percarbonate) is the safe alternative at 40-60 °C.

Wash cycle sequence: pre-wash/flush, main wash with detergent, rinse, fabric conditioner in the final rinse, then extraction (spin).

Low-temperature programmes (30-40 °C) save energy but need longer time or enzyme detergent to match the cleaning result of 60 °C.

Wool and silk use a gentle/delicate cycle at 30 °C or hand wash, low agitation and low spin, with a neutral or wool-specific detergent.

Sorting rules: by colour (white, light, dark), by fibre and construction, and by degree of soiling; new dark garments are washed separately to avoid bleeding.

Load the drum loosely - roughly 80 % of drum volume - so that mechanical action can occur; overloading causes poor rinsing and creasing.

Bleach must never be mixed with acid or ammonia; chlorine bleach plus acid releases toxic chlorine gas.

Soaking time is typically 15-30 minutes; prolonged soaking of protein-stained or viscose items risks dye bleed and fibre damage.

Hard water requires water softener or a builder in the detergent; otherwise soap forms scum and detergent performance drops.

Soap is a salt of a fatty acid (e.g., sodium stearate); it is biodegradable but forms insoluble scum with calcium and magnesium in hard water.

A detergent molecule has a hydrophilic head and a hydrophobic tail; micelle formation lifts oily soil into the wash liquor.

Surfactant types: anionic (best on cotton, good oily soil removal, high foaming), non-ionic (low foam, good on synthetics, works at low temperature), cationic (fabric softeners, germicidal), amphoteric (mild, used in shampoos and gentle detergents).

Builders soften water and supply alkalinity: sodium carbonate, sodium silicate, zeolites (4A), citrates; phosphates are restricted because of eutrophication.

Enzymes are substrate-specific: protease (protein), amylase (starch), lipase (fat), cellulase (fuzz/cotton surface). Enzymes work best at 30-50 °C and are denatured above about 60 °C.

Optical brighteners absorb UV and re-emit blue light, making white fabric appear brighter; they are not bleaches and do not remove soil.

Detergent pH: soap and carbonate-built powders are alkaline (pH 9-11); wool-safe detergents are neutral to mildly acidic (pH 5.5-7).

Foam height is not a measure of cleaning power; low-foam non-ionic detergents suit front-loading machines and automatic dosing.

Front-loading machines use a tumbling action with low water and low foam; top-loaders use an agitator with higher mechanical action and water use.

Drum capacity is rated in kilograms of dry load; overloading beyond the rating damages bearings and reduces cleaning.

Steam boiler/iron temperatures: cotton 180-220 °C, linen up to 230 °C, wool 150-160 °C, silk 120-140 °C, polyester 110-150 °C.

Electrical safety: RCD/earth leakage protection, no wet hands on plugs, damaged cords replaced, machines on a dedicated circuit.

Chemical safety: store alkalis and acids separately, keep SDS (safety data sheets) accessible, and never decant chemicals into unlabelled bottles.

Personal protective equipment for spotting and dyeing: nitrile gloves, goggles, apron, and ventilation for solvent and dye powder handling.

Dye powder is a respiratory sensitiser; weigh it in a ventilated area and wear a dust mask when handling powdered dyes.

Tumble dryer lint filters must be cleaned every cycle; lint build-up is a fire hazard and reduces drying efficiency.

Ironing moves the iron over the fabric; pressing applies the iron with pressure and lift; mangling passes fabric between heated rollers for flatwork.

Moisture plus heat plus pressure sets the shape: cotton and linen are pressed damp, wool is steamed and pressed dry with a cloth.

Iron temperature order from low to high: acetate, silk, wool, polyester, cotton, linen.

Ironing on the wrong side protects lustre and prevents shine on wool and dark synthetics; use a pressing cloth for delicate or embellished items.

Steam relaxes fibres and removes creases; too much steam on viscose or wool can stretch the garment, so support the full weight.

Permanent press and resin finishes can be damaged by high iron temperatures, causing glazing or a permanent shine.

Folding and hanging: knits are folded flat to prevent shoulder stretch; woven shirts and trousers are hung on shaped hangers.

Spotting and pressing must be separated; pressing a stained garment sets the stain and makes removal nearly impossible.

Dye uptake depends on fibre chemistry: cellulose (cotton, viscose) takes direct, reactive and vat dyes; protein (wool, silk) takes acid, reactive and metal-complex dyes; polyester takes disperse dyes.

Exhaustion is the proportion of dye transferred from the bath to the fibre; fixation is the proportion chemically or physically locked into the fibre.

Dyeing rate is controlled by temperature, pH, electrolyte (salt) concentration and auxiliaries (levelling agents, retarders).

Salt (sodium chloride or sulphate) promotes exhaustion of direct and reactive dyes on cellulose by reducing the electrical barrier.

Alkali (soda ash) fixes reactive dyes by forming covalent bonds with cellulose hydroxyl groups.

Acid dyes on wool need acid (acetic or formic) to protonate the fibre and attract the anionic dye; too fast acid addition causes unevenness.

Disperse dyes on polyester require high temperature (about 130 °C under pressure) or a carrier, because the fibre is hydrophobic and tightly packed.

Colour fastness is rated 1-5 on grey scales (ISO 105): 5 means no change or staining; fastness to washing, light, rubbing and perspiration are the usual tests.

Direct dyes: water-soluble, applied to cellulose with salt, simple but moderate wash fastness; often after-treated for improvement.

Reactive dyes: form covalent bonds with the fibre, giving high wash fastness on cotton; require salt and alkali and thorough soaping-off of unfixed dye.

Vat dyes (indigo, vat blue): insoluble pigments reduced to a soluble leuco form in alkaline sodium hydrosulphite, applied to cellulose, then oxidised back in the fibre.

Acid dyes: anionic, applied to wool, silk and nylon in an acid bath; bright shades but variable light fastness.

Disperse dyes: sparingly soluble, applied as a dispersion to polyester, acetate and nylon; the only practical class for polyester.

Basic (cationic) dyes: applied to acrylic and, with a mordant, to wool and silk; very bright but poor light fastness on many substrates.

Sulphur dyes: cheap, dark shades (black, navy, brown) on cotton with good wash fastness but poor light fastness and environmental concerns.

Pigments are insoluble and are fixed with a binder rather than by affinity; used in textile printing and garment dyeing of blends.

Exhaust dyeing: the fibre and the bath are heated together with agitation; the liquor-to-goods ratio (e.g., 1:10 to 1:20) determines dye concentration.

Pad-dyeing: fabric is passed through the dye liquor, squeezed to a fixed pick-up (often 60-80 %), then fixed by steam, dry heat or cold batching.

Cold pad-batch: padding with reactive dye and alkali, then batching at room temperature for 12-24 hours; saves energy and suits small runs.

Garment dyeing is used for fashion shades and stock control, but seams, zips and trims may dye differently from the main fabric.

Tie-dye and batik are resist methods: the resist (binding or wax) prevents dye access and creates the pattern.

Levelness is improved by starting at low temperature, adding dye slowly, controlling pH and using a levelling agent.

After-treatment: rinsing, soaping-off (reactive), oxidation (vat), and back-tanning or fixing agents where fastness must be improved.

Dyeing faults: patchiness from poor agitation, barré from yarn variation, bronzing from too much dye, and tippiness from uneven fibre maturity.

The wash tub symbol gives the maximum wash temperature in °C; a hand in the tub means hand wash only; a crossed tub means do not wash.

A triangle means bleaching is allowed; diagonal lines inside mean oxygen (non-chlorine) bleach only; a crossed triangle means no bleach.

A square with a circle is tumble drying; dots give heat level - 1 dot low, 2 dots medium, 3 dots high; a crossed symbol means do not tumble dry.

An iron symbol with dots: 1 dot about 110 °C (synthetics), 2 dots about 150 °C (wool/polyester blend), 3 dots about 200 °C (cotton/linen).

A circle means dry cleaning; the letter inside (P, F, A) tells the solvent class; a crossed circle means do not dry clean.

A square with a horizontal line means dry flat; with a vertical line means line dry; with three vertical lines means drip dry.

Care labels are permanent and must reflect the harshest treatment the garment can take; fibre content must be stated on the label.

Symbols are read in order: wash, bleach, dry, iron, professional care; a crossed symbol is an absolute prohibition.

Store clean garments: body oils and perspiration oxidise over time and cause yellowing that is hard to reverse.

Wool and silk are protein fibres and are attacked by clothes moths and carpet beetles; store in sealed bags with cedar or lavender.

Viscose loses strength when wet and must be dried flat, reshaped while damp, and never hung wet on a hanger.

Knits are stored folded, not hung, to avoid shoulder distortion; heavy beaded garments are stored flat.

Sunlight degrades cellulose and many dyes; store garments away from direct light, and dry coloured items in the shade.

Polyester and nylon are thermoplastic: cool before folding after ironing, or permanent creases form.

Mould grows on damp natural fibres; storage humidity should stay below about 60 % RH and garments must be fully dry.

Leather and suede need ventilation, not plastic bags, and should be kept away from direct heat.

Break-even quantity = fixed costs / (price per unit − variable cost per unit); it shows the minimum order volume needed to avoid loss.

Pricing for a laundry service should cover chemicals, utilities, labour, machine depreciation and overhead, plus a profit margin.

Value-added services (stain removal, ironing only, pick-up and delivery, dry cleaning of formal wear) raise average revenue per customer.

Record keeping: daily cash book, order register with garment count and condition notes, and a simple profit-and-loss statement each month.

Customer acquisition for a small laundry relies on location, word of mouth, visible quality (packaging, finishing) and transparent pricing.

Working capital is needed for detergent stock, rent, electricity and wages before payment is collected from contract customers.

A written order slip signed by the customer, noting pre-existing damage, is the main protection against damage claims.

Government support for small enterprises commonly includes subsidised loans, skill training and registration under the local MSME framework.

Workflow layout: reception and tagging, sorting, washing, drying, spotting, finishing, quality check, packing and delivery - each in a defined zone.

Tag every garment at intake with a unique order number; loose tags and pin marks cause mix-ups and damage claims.

Quality check before packing: no stains, no missing buttons, correct crease, correct garment count against the order slip.

Chemical stock control: label, date of opening, keep away from food, and rotate stock using first-in-first-out.

Housekeeping and safety: dry floors, spill kits, fire extinguisher suitable for electrical and chemical fires, and clear exits.

Customer complaint handling: listen, inspect the garment, refer to the signed order slip, and offer a defined remedy (re-clean, repair or compensation).

Staff training in fibre identification and stain removal reduces costly errors more than any other single measure.

Turnaround time and capacity planning: estimate daily capacity in kilograms, and do not accept orders beyond capacity during peak seasons.

The care label is the final authority: if a customer requests a treatment the label forbids, record the instruction in writing before proceeding.

Fibre plus construction decide the care method; two garments of the same fibre can carry different labels because of trims, dyes or finishes.

A 'dry clean only' label on viscose or wool usually reflects shrinkage or finish risk, not fibre weakness alone.

Symbols on imported garments may follow ISO 3758 or national variants; when in doubt, use the mildest interpretation.

Never remove or cover a care label during cleaning; it is the reference for the customer and for any claim.

Colour-fastness test before any wet treatment: apply the agent to a hidden seam and blot with white cloth after 5 minutes.

Care instructions must be passed on to the customer at delivery, especially for the first wash of dark or new garments.

Spotting before washing, not after: heat in the wash or dryer sets protein and tannin stains permanently.

Match the spotting agent to the stain class, then match the wash programme to the fibre; the two decisions are independent.

Flush with the solvent that matches the agent: water-based agents are flushed with water, solvent agents with solvent, to avoid rings.

Enzyme detergents at 30-40 °C handle protein and starch residues that spotting alone may leave behind.

After spotting, always rinse and dry the area before pressing, or the chemical can concentrate and damage the fibre.

Record every spotting treatment on the order slip, including agent and time, so a claim can be assessed fairly.

If a stain cannot be removed after two safe attempts, stop and inform the customer rather than risk fibre damage.

Weigh dyes and chemicals to 0.01 g accuracy; small errors change shade noticeably in small batches.

Prepare a stock solution for small shade adjustments rather than weighing powder repeatedly.

Match shade under standard daylight or a D65 lamp; metamerism means two samples can match under one light and differ under another.

Record the recipe as percentage on weight of fibre (owf), liquor ratio, temperature profile, pH and time, so the shade can be repeated.

Rinse and dry the sample before judging the final shade; wet fabric appears darker than dry fabric.

Dye powders are hazardous: wear a dust mask and gloves, and never eat or drink in the dye area.

Spent dye baths must be treated before disposal; heavy metals and unfixed dye should not enter drains untreated.

Washing machine not draining: check the filter, drain hose kinks and pump; a blocked coin trap is the most common cause.

Excessive vibration on spin: an unbalanced load, worn shock absorbers or a machine not levelled on the floor.

Poor cleaning result: check detergent dose, water hardness, loading, temperature and programme before suspecting the machine.

Lint on dark garments: clean the lint filter, separate lint-shedding from lint-attracting fabrics, and check the dryer.

Iron not steaming: descale the boiler, check the water type recommended by the maker, and clean the soleplate with a suitable agent.

Preventive maintenance schedule: daily filter clean, weekly drum and detergent drawer clean, monthly descaling check, annual service.

Electrical faults must be handled by a qualified technician; never bypass an earth connection or a safety interlock.

Intake inspection must record existing damage, missing buttons, faded areas and previous repairs, with the customer's signature.

Explain realistically what can and cannot be removed; never promise a result that the fibre or stain class makes unlikely.

A claim is assessed against the order slip, the care label and the treatment record, not against the customer's recollection alone.

Offer a clear remedy ladder: re-clean, repair, replacement or compensation, and state the time frame.

Keep damaged garments until the claim is settled; disposal without consent weakens the business position.

Complaint response time matters more than the size of the compensation for repeat custom.

Train counter staff to identify fibre and label symbols at intake; most disputes begin with a wrong promise at the counter.

A typical laundry uses 10-20 litres of water per kilogram of work; low-liquor machines reduce this substantially.

Water hardness above 180 mg/L CaCO3 requires softening to prevent scum, grey whites and excess detergent use.

Wastewater from dyeing carries unfixed dye, salt and alkali; pH must be neutralised before discharge.

Heat recovery from hot effluent and from dryer exhaust reduces energy cost per kilogram.

Cold-water detergents and enzymes reduce energy use but need longer cycle time to match hot-wash results.

Dosing accuracy prevents both under-washing and chemical waste; automatic dosing is more consistent than manual scoops.

Reuse of rinse water for the pre-wash stage is a common low-cost water-saving measure.

Dimensional stability: measure length and width before and after a standard wash; shrinkage above the label allowance is a fault.

Colour fastness to washing is rated 1-5 for colour change and for staining of adjacent multifibre strip.

Rubbing fastness (wet and dry) uses a crockmeter; wet rubbing fastness is usually lower than dry.

Light fastness is rated 1-8 on the blue wool scale, where 8 is best; azo dyes vary widely.

pH of the aqueous extract of a garment should be near neutral (about 4.0-7.5) to avoid skin irritation.

Pilling is assessed on a 1-5 photographic scale after abrasion; synthetic blends pill more than long-staple natural fibres.

Incoming inspection of contract work should sample at least 10 % of garments against the order specification.

Shine on wool or dark synthetics comes from too much pressure or direct heat; use a pressing cloth and steam.

Glazing (a permanent lustrous mark) occurs above the fibre's safe temperature and cannot be reversed.

Scorch marks are brown or yellow discolouration from excessive heat; light scorch may be removed by gentle bleaching, heavy scorch is permanent.

Double creases come from careless folding under the iron; press flat, lift and reposition rather than dragging.

Water spots on silk come from droplets; steam evenly and dry the whole area to avoid rings.

Iron marks on thermoplastic fibres (acetate, polyester) are melted fibre and are irreversible.

Correct pressing sequence: seams and inside first, then face side, then folds; cool before folding to set the crease.

Beaded and sequinned garments are cleaned by hand or specialist dry cleaning, padded to protect the embellishment, and never tumble dried.

Leather and suede require specialist cleaning; water causes hardening and colour loss, so only the recommended solvent is used.

Embroidered and lace items are washed in a mesh bag on a gentle cycle, or hand washed, and dried flat.

Down-filled items need a low-heat tumble dry with dryer balls to redistribute the filling and prevent clumping.

Wedding dresses are inspected for sugar, wine and perspiration stains, treated before storage, and packed in acid-free tissue.

Woollen sweaters are washed in cool water with wool detergent, spun lightly, reshaped and dried flat.

Waterproof and coated fabrics lose their finish with normal detergent and heat; use a technical-fabric wash and air dry.

Cost per kilogram = (chemicals + utilities + labour + depreciation + overhead) / kilograms processed in the period.

Productivity is measured as kilograms per operator-hour; layout and batch size affect it more than individual speed.

Utility cost is usually dominated by heating water and running dryers; lowering wash temperature saves the most energy.

Chemical cost per kilogram is small compared with labour and utilities in most laundries, so under-dosing to save money is a false economy.

Machine utilisation below about 60 % means fixed costs per kilogram rise sharply.

Re-work (re-cleaning a failed item) roughly doubles the cost of that item and should be tracked as a quality indicator.

Break-even analysis should be recalculated whenever detergent prices, electricity tariffs or wages change.