A double process hair color, also known as full highlights, is a technique where both the hair’s natural pigment and artificial color are changed. This process involves applying bleach and hair dye to strip and alter the hair’s underlying pigment before depositing a new hair color. As a more intensive process than regular highlights or a single process color, double process hair coloring takes more time and expertise to complete.
What is a double process hair color?
A double process hair color involves two steps:
- Bleaching – Lightener or bleach is applied first to strip the hair’s underlying pigment and allow access to the hair cuticle. This destroys the hair’s original color molecules and removes warmth or brassiness.
- Coloring – After rinsing the bleach, permanent hair dye is applied. The hair dye penetrates the now decolorized cuticle and cortex to deposit new color pigments.
When performed correctly, double processing allows for drastic, vibrant color changes that would be impossible with a single process. It lightens the hair’s base to pale yellow or white before overlaying a bright shade like platinum blonde, pastel pink, or neon blue.
How long does each step take?
On average, the bleaching steps takes 30-45 minutes. However, timing depends on:
- Hair length and thickness – Longer, denser hair requires more lightener and longer processing.
- Desired lightness – Lightening dark hair to pale blonde requires more time than subtle highlighting.
- Product used – Higher volume developers speed up lightening.
- Hair’s starting shade – Naturally lighter hair lifts quicker than dark hair.
After rinsing out the bleach, the coloring step takes 10-30 minutes with most permanent dyes. Again, timing varies based on hair thickness, product choice, and desired vibrancy of color. Quicker semi-permanent dyes may process in as little as 5 minutes.
How long does the entire process take?
From start to finish, a double process hair coloring often takes 2-3 hours. Here is a rough timeline:
| Stage | Duration |
|---|---|
| Consultation and planning | 15-30 minutes |
| Preparing and sectioning hair | 15-30 minutes |
| Applying lightener | 30-45 minutes |
| Rinsing and drying | 15-30 minutes |
| Applying color | 10-30 minutes |
| Rinsing and drying | 15-30 minutes |
| Toners and treatments | 15-30 minutes |
| Total Time | 2-3 hours |
Salon visits for double processing generally last between 2-4 hours. Time will vary depending on your stylist’s pace and number of clients. At busier times, your appointment may be split into two separate visits.
Does hair thickness change processing time?
Yes, thicker hair tends to require longer processing times for bleach and dye. Hair thickness is determined by the number of individual strands on your head:
- Fine hair – Has a small diameter and dense growth. Usually straight hair. Requires less time to process.
- Medium hair – Has a mix of thick and thin strands. Medium density. Average processing time.
- Thick hair – Has predominantly wide, dense hair strands. Usually curly or wavy hair. Needs longer processing.
As a general guideline:
- Fine hair – 30-40 minutes bleaching, 15-20 minutes coloring
- Medium hair – 35-45 minutes bleaching, 20-25 minutes coloring
- Thick hair – 45-60 minutes bleaching, 25-30 minutes coloring
Other factors like hair health and porousness also impact processing times.
Does hair length change processing time?
Yes, longer hair tends to require more time to lighten and color evenly. General timeframes based on length include:
- Short hair (above shoulders) – 30-45 minutes bleaching, 15-25 minutes coloring
- Medium hair (between shoulders and bra strap) – 45-60 minutes bleaching, 20-30 minutes coloring
- Long hair (below bra strap) – 60+ minutes bleaching, 30+ minutes coloring
The longer the hair, the more overall lightener and dye needed. This often involves sectioning hair multiple times to ensure even saturation. Stylists should use thinner sub-sections for longer hair.
Do different dyes impact timing?
Yes, permanent vs semi-permanent dyes require different processing durations. Here is a comparison:
- Permanent hair dye – Lasts 4-6 weeks. Uses peroxide developers to open the cuticle and deposit color inside the hair shaft. Requires 20-30 minutes processing.
- Semi-permanent hair dye – Lasts 4-8 shampoos. Coats the outside of the hair rather than penetrating the cortex. Requires only 5-15 minutes processing.
Permanent dyes produce longer-lasting, fade-resistant color. But semi-permanents involve less commitment and damage for short-term vivid shades. Talk to your stylist about the option that best fits your goals.
What affects the bleaching time?
Several factors impact how quickly lightener can lift and decolorize hair:
- Developer volume – Higher volume peroxide speeds up lightening. But can increase damage if overused.
- Hair’s base color – Naturally lighter hair bleachs quicker than darker shades.
- Hair health – Damage makes hair more porous so it lightens faster.
- Product used – Professional lighteners lift faster and more safely than box kits.
- Body heat – Warmth from scalp and room speeds up bleaching.
An experienced stylist considers all these elements when formulating and timing your lightening service. This prevents over-processing and unnecessary damage to hair.
What maintenance is required after?
Double process hair coloring looks stunning, but requires diligent upkeep. To keep hair healthy and color vibrant:
- Use restorative hair masks and leave-in conditioners.
- Rinse hair with cool water and limit washing to 2-3 times per week.
- Use sulfate-free shampoo and purple shampoo for toning.
- Apply heat protectant before hot tools.
- Get a trim every 6 weeks to prevent split ends.
- Use gloss treatments between full color appointments.
- Avoid chlorine, salt water, and sun damage.
Full color touch-ups are needed every 4-6 weeks as the new growth comes in. Schedule maintenance appointments well in advance to ensure availability and continuity.
Conclusion
Double process hair coloring produces beautiful, vibrant results when performed correctly. But the intensive lightening and coloring steps require significant time and expertise. From consultation to drying and styling, appointments typically last 2-4 hours based on your hair’s thickness, length, and condition. Maintaining this look also involves diligent at-home care and frequent touch-ups. While a sizable time commitment, a double process can let you rock almost any fashionable hue.
