No, you should not use hair dye that's been mixed if it's been more than an hour.
Why You Can't Reuse Mixed Hair Dye
Mixed hair dye has a very short lifespan and must be used within 1 hour of mixing. According to the reference, mixed hair dye:
- Has no shelf life.
- Is dangerous to store.
- Cannot be used at a later date.
Why is this the case?
Once you mix the developer and the color cream, a chemical reaction starts. This reaction is what allows the hair dye to work. Over time, the chemical reaction can change, become unstable and lead to unpredictable results, or even skin or scalp irritation if the dye is used too long after mixing.
Safety Tips for Hair Dyeing
- Always mix the dye immediately before use. Do not prepare it in advance.
- Use the dye within the recommended time frame. In this case, one hour after mixing.
- Discard any unused mixed dye. Never attempt to store and use leftover mixtures later.
- Carefully follow the instructions on the product packaging. Manufacturer guidelines are essential for optimal results and safety.
Summary
| Consideration | Recommendation |
|---|---|
| Mixing Time | Mix hair dye immediately before you are going to use it. |
| Usage Window | Use mixed dye within 1 hour of mixing. |
| Storage | Do not store mixed hair dye. Discard unused portions. |
| Safety | Stored or used too late mixed dye can lead to poor results and potentially skin irritations. |
