As many bottle blondes out there will know, lightening your hair can be a bit of a minefield. Dodging brassiness and breakages left and right, the endless salon treatments may carve a sizeable dent in your hard-earned cash. Purple shampoo is already a friend to many, neutralising those brassy, red-orange strands in the comfort of your own shower – but it has its downsides. Its toning properties often dry out hair and can leave it looking dull and lacklustre.
That's where Olaplex (the brand of cult status) comes in. Olaplex quite rightly causes a stir with each product release, for example the new No.8 Bond Intense Moisture Mask and No.0 Intensive Bond Building Hair Treatment. Its latest — the No 4P Blonde Enhancer Toning Shampoo, £26 — is already receiving rave reviews across social media, not just for its toning abilities but for its strengthening and hydrating properties, too.
An update on Olaplex’s classic No 4 Bond Maintenance Shampoo, it shares the same patented active ingredient that seeks out the broken bonds in your hair (those caused by chemical, thermal and mechanical damage) and repairs them. The molecules work to regenerate growth, cleanse from root to tip and give hair an intense surge of moisture. As a result, hair is cared for from the inside out, and looks and feels strong, soft and shiny.
The technology has now been merged with a purple toner – a high concentration of pigment that comes out in a deep, cool-toned violet shade. Olaplex promises blonde hair "three times brighter" than other purple shampoos, without any annoying purple patches. Even better, like the rest of the Olaplex range, it's totally sulphate-free (so it won't strip colour or keratin-treated hair). It's recommended for brightening grey hair, too. Given that purple shampoo can often be drying on the hair and scalp, it’s no wonder this product has swiftly become a much-recommended post-dye saviour. You can shop Olaplex’s No 4P Blonde Enhancer Toning Shampoo now at Cult Beauty, £26.
How does purple shampoo work?
Purple shampoos are used to balance out and control yellow tones – the underlying pigment in blonde hair. “Think about the colour wheel: opposites attract,” Francesca says. “Purple balances out yellow tones and revives dull blonde hair.” Francesca recommends purple shampoo to all her blonde clients as it prolongs their colour. “They are a way to upkeep your blonde at home in between colour appointments,” she continues. “It's not a permanent solution as they don't have ammonia in them, but they are great for anyone who is experiencing brassiness and isn't ready to come back in.”
How do I use purple shampoo?
Francesca suggests starting off with a clarifying shampoo rather than your purple shampoo. “I would recommend a clarifying shampoo whenever possible,” she says. “Over-shampooing strips the natural oils (which make it healthy and strong) out of your hair. But for times when you need to hit the refresh button (if hair is looking a little dull), a clarifying shampoo rids hair of excess product build-up that blocks its shine, without harming your hair colour."
As a beginner, using Olaplex’s purple shampoo might be a bit unnerving – it really is highly pigmented. But that’s a good thing. The darker the shampoo, the better its brightening powers (a tip to remember whenever shopping for purple shampoo). Taking this into consideration, beginners might want to mix Olaplex with their usual shampoo, using half and half at first. If you’re a little more confident with purple shampoo, you can go straight in. Either way, always start with wet hair and lather up the shampoo fully. For a lighter touch, Olaplex recommends leaving it to process for one to three minutes.
For a more intense toning, Francesca has an alternative method. “Rather than using purple shampoo like a regular shampoo (massaging it in quickly and then rinsing it out), we recommend slowing down the application process for better results,” she says. “Rinsing it off too quickly makes it less effective so I recommend applying it on damp, towel-dried hair as if you were applying a mask, combing it through evenly and leaving it on. About five minutes is the most effective.”
How often should I use purple shampoo?
While Olaplex says you can use its purple shampoo as often as you would like, you’ll swiftly work out the right amount for yourself. Depending on your hair colour and the colour treatment you book, Francesca recommends using purple shampoo at home once every few weeks to refresh and to keep yellow tones at bay.
In fact, overuse of purple shampoo is a common mistake she sees. “Most purple shampoos should not replace your regular cleanser every day or even multiple times per week,” she explains. “Speak to your stylist about the best product for you and how often to apply it, I usually suggest once every two weeks. Otherwise, an overdose of cool-toned purple could make your hair appear darker and more dull. Limited use allows for the warmer tones in your strands to reflect more light for a healthier overall look.”
What are the other best purple shampoos on the market?
If you're in the market for a new purple shampoo, you want to consider your options. Francesca loves L'Oréal Professionnel Serie Expert Blondifier Cool Shampoo, £13.40, and here are a handful of R29's favourites...
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