Sweat Stain Remover for Shirts & Sportswear
Yellow underarm stains are not really sweat — they're the residue of sweat protein reacting with aluminium in antiperspirant, baked in by body heat and the dryer. Luniva's protease active enzymes break down the protein bond in 5 minutes, lifting fresh sweat patches and old yellow stains without bleach.
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Why sweat stains turn yellow and stay yellow
Eccrine sweat is mostly water and salt — it doesn't stain on its own. Antiperspirant aluminium chlorohydrate binds with the protein in sweat to form a yellow complex that bonds tightly to cotton. Bleach makes it worse; only an active enzyme protease will reliably break it down.
How to use Luniva on sweat & underarm stains
- Step 1 — Saturate the underarm area: Spray Luniva over the whole pit area until visibly wet. Don't rub.
- Step 2 — Wait 5 minutes: Protease active enzymes break down the sweat-aluminium bond. For old yellowing, leave 10 minutes.
- Step 3 — Wash at 40°C, air-dry first: Run a normal cycle. Inspect before tumble-drying — heat re-sets any residue.
Compliance note: Based on controlled laboratory testing. Performance may vary by stain age, fabric type and wash conditions.
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Frequently asked questions
Why do my white shirts have yellow underarm stains?
It's the sweat protein reacting with aluminium in antiperspirant. Luniva's protease active enzymes break the bond — spray, wait 5–10 minutes, wash at 40°C.
Does Luniva remove sweat smells from sportswear?
Yes. Sweat odour is caused by bacteria feeding on protein residue in the fabric. Removing the residue removes the smell. Spray problem areas, leave 5 minutes, wash at 40°C.
Will Luniva fade my coloured gym shirts?
No — Luniva is active enzyme-based and bleach-free, safe on dyed polyester and cotton blends.
Can I use Luniva on bras and delicates?
Yes. Spot-test the underwire and lace first. If safe, spray lightly, wait 3 minutes, hand-wash in cool water.
Why does the yellow stain come back after washing?
If the stain wasn't fully digested, residual protein re-oxidises as the garment dries. Repeat the Luniva treatment with a 10-minute dwell time and air-dry in sunlight.