Demi Dye Assalt Deep
DEMI Assalt Deep is the professional deep-tone segment within DEMI's Assalt Arias Japanese hair color system. The 10+ in-stock shades span depth levels D-4 (dark brown) through D-9 (light brown) and are available in WB (Warm Beige), CB (Cool Beige), and BB (Bright Beige) tone variants at each depth. The Assalt Deep formulas are built for consistently saturated, dimension-rich brunette results with low-ammonia oxidation technology. Whether the goal is dense gray coverage at D-4 or a soft natural light brown at D-9, the formula maintains the same conditioning quality across the depth range.
By Skinsli editorial Updated
You've reached the end
Buying guide
DEMI Assalt Deep Hair Color: Shade Decoding and Professional Use Guide
DEMI Assalt Deep is the professional deep-tone hair color segment from DEMI's Assalt Arias system. With 10+ shades across depths D-4 to D-9 and three tone variants per depth, the system is structured to let colorists dial in both richness and warmth/coolness independently. This guide decodes the shade code system, explains how the formula handles depth and gray, and outlines application best practices for professional salon use.
Where Assalt Deep Sits in the DEMI System
Within DEMI's Assalt Arias professional line, the Deep Natural sub-range is the core natural brunette collection. It does not include high-lift, fashion, or direct dye formulas. The entire depth range (D-4 to D-9) sits within the natural brown corridor, making this the right choice for clients whose goal is a clean, dimensional natural brown rather than a visible color transformation. This also means Assalt Deep is not the tool for going lighter than the starting depth - it is a deposit-and-cover system.
Depth Code Decoding: D-4 Through D-9
The D number maps to the international depth scale: D-4 is dark brown, D-5 is medium dark brown, D-7 is medium brown, D-8 is light medium brown, D-9 is light brown. In the current in-stock range, D-4 through D-9 are all represented. D-5 and D-7 have the fullest tone matrix with WB, CB, and BB variants; D-4, D-8, and D-9 have WB available and select CB options. Note that D-6 is not currently stocked - clients between D-5 and D-7 in natural level can typically be placed at either depending on their desired outcome direction.
Tone Variants: WB, CB, and BB Explained
WB (Warm Beige) gives the finished result a golden or honey direction. CB (Cool Beige) introduces ash or neutral-cool quality - it counteracts warmth in the underlying hair or from previous color services. BB (Bright Beige) is the most balanced of the three, producing a bright, clean result without a strong warm or cool direction. For most first-time Assalt Deep clients without a specific tone preference, BB is the lowest-risk choice at any depth.
Gray Coverage: How It Works at Each Depth
Assalt Deep provides reliable gray coverage across the depth range with standard developer concentrations. At D-4 and D-5, even dense or resistant gray will be covered with a 30-minute room-temperature process at 1:1.5 mixing ratio. At D-7 and D-8, clients with 60-80% white hair will see solid coverage with good saturation. At D-9, very high concentrations of white hair produce a softer blended brunette effect rather than full opacity, which is often the more flattering outcome at lighter depths.
Developer and Mixing Guide for Assalt Deep
The standard mix is 1 part DEMI Assalt color to 1.5 parts DEMI developer. Use 3% (10 vol) for deposit and gray coverage without any lift. Use 6% (20 vol) if one level of lift is needed alongside the color deposit. Avoid higher developer concentrations within the Deep Natural range, as they introduce unpredictable warmth during the lift phase that conflicts with the controlled CB and WB tone axes. Mix in a non-metallic bowl and apply within 30 minutes.
Root Touch-Up Application
For regrowth applications, apply the mixed color only to the new growth zone and avoid overlapping with previously colored hair unless a tone refresh across the whole length is intended. Overlapping with existing color adds unnecessary chemical exposure and can build up a band of darker, heavier color at the root-to-mid junction over multiple services. A precise, brush-based application to the regrowth alone gives the cleanest result and fastest grow-out.
Formula Quality: Conditioning and Post-Color Feel
DEMI's low-ammonia formulation includes conditioning agents in the color base that reduce cuticle swelling during oxidation. The practical result is a smoother, softer hair feel after drying compared to higher-ammonia European color formulas. This is especially noticeable on fine or previously processed hair. DEMI color is not a conditioning treatment substitute for significantly damaged hair, but it minimizes the structural disruption of the color process on normal to moderately processed hair.
Choosing the Right Depth for Natural Dark Results
D-4 WB is the darkest available shade in the in-stock range. It is appropriate for clients who want the darkest possible natural brown or who need to match a very dark natural hair color. D-5 WB or D-5 CB is more commonly used when the goal is a dark brown that still reads as brown rather than near-black, which gives the result a slightly more dimensional appearance in different lighting conditions.
Aftercare to Maintain Assalt Deep Color
Clients should use a color-safe, sulfate-free shampoo from their first wash after service. A 48-hour wait before the first wash gives the oxidative process time to fully stabilize. Thermal styling tools should be used with a heat protectant, as heat is one of the primary drivers of color fade on the mid-lengths and ends. Clients using CB (Cool Beige) variants should be advised that ash tones fade faster than warm tones, and a monthly tone refresh or use of a blue-tinted color-protecting shampoo will extend the cool result.
FAQ
Frequently asked questions
FAQ
Frequently asked questions
What does 'Assalt Deep' mean in the DEMI hair color system?
Assalt is DEMI's professional oxidative color sub-brand name, and Deep Natural is the segment within it focused on rich, dimension-filled natural brunette shades. The 'Deep' label signals saturated, full-deposit color in the natural brown corridor rather than fashion or high-lift shades. It is the core professional collection for clients who want clean gray coverage or a natural brown enhancement without visible artificiality.
Is D-4 the darkest shade available in DEMI Assalt Deep?
Yes, D-4 WB is the darkest depth in the current in-stock range. It reads as a very dark brown that can appear near-black in low light. If a client wants a result that stays definitively brown even in indoor lighting, D-5 is generally a better choice. D-4 is best reserved for clients who specifically need to match existing dark hair or require maximum depth for dense gray coverage.
Can DEMI Assalt Deep produce fashion colors or very light results?
No. The Deep Natural line is formulated exclusively for natural brunette results in the D-4 to D-9 depth corridor. It does not include high-lift, pastel, or vivid fashion shades. For results lighter than D-9 or any fashion-directed color, a different DEMI line or a pre-lightening step would be required before the Deep Natural color is applied.
Which DEMI Assalt Deep shade gives the most ash or cool brown result?
CB (Cool Beige) variants are the most ash-leaning choices at any depth. D-7 CB and D-5 CB are the most requested cool brunette options in the current in-stock range. D-8 CB is available for clients who want a lighter ash brown result. Apply over clean or slightly faded hair for the strongest cool deposit; over existing warm tones, the CB pigment will partially neutralize warmth but may not fully ash very brassy underlying hair in a single application.
What result does the BB (Bright Beige) variant produce compared to WB and CB?
BB (Bright Beige) produces a clean, luminous brown without a strong warm or cool direction. It is the most universally flattering option when the client does not have a specific tone preference. BB tends to look brighter and more reflective than CB without the golden warmth of WB. At D-5 BB and D-7 BB it is a reliable default for clients who simply want 'a nice natural brown.'
Can DEMI Assalt Deep be applied over pre-lightened or bleached hair?
Yes. Applying Assalt Deep WB or BB over pre-lightened hair is a common technique for adding a warm or neutral brunette tone back onto a light base. The color deposit is predictable on lifted hair because the underlying warmth has already been removed. Use a 3% developer and mix at 1:1.5 for a full deposit. Note that color on pre-lightened hair fades faster than on natural hair, so the tone refresh cycle will be shorter.
Why does the 1:1.5 mixing ratio matter for DEMI Assalt Deep color?
The 1:1.5 ratio (color to developer) is calibrated for full pigment deposit with enough developer volume to activate the oxidation chemistry completely. A thinner mix (1:2 or higher) dilutes the pigment load and can result in a lighter, less saturated result than the shade card suggests. A thicker mix (1:1 or less) can make the formula difficult to spread evenly through the hair and may slow developer penetration. Stick to the 1:1.5 default unless you are deliberately adjusting the result.
Is D-9 WB suitable for a warm light brown natural result?
Yes, D-9 WB is the lightest warm tone available in the current Assalt Deep in-stock range. It produces a light golden brown result with a warm, honey-adjacent direction. On hair with more than 50% gray, D-9 WB will produce a softer, lighter result that may read as a warm blonde at the gray sections - which many clients find attractive as a blended natural finish rather than aiming for full coverage at this depth.
Can repeated DEMI Assalt Deep applications cause sensitization over time?
All oxidative hair color systems, including DEMI Assalt Arias, carry a risk of sensitization with repeated exposure to p-phenylenediamine (PPD) and related compounds. A patch test before every service is the professional standard for managing this risk. If a client reports any scalp itching, burning, or swelling during or after a service, discontinue use and advise them to consult a dermatologist before any further color applications.
Where is DEMI Assalt Arias Deep Natural Line manufactured?
DEMI is a Japanese professional beauty brand and all Assalt Arias products are manufactured in Japan. Products are produced under Japanese cosmetic regulatory standards, which require ingredient safety documentation and pre-market quality testing. All products on skinsli.com are sourced through authorized wholesale channels and arrive in original, unaltered packaging.
How quickly does DEMI Assalt Deep color fade, and which variants fade fastest?
Under normal washing conditions (two to three times per week with color-safe shampoo), the main tone holds for four to six weeks before noticeable fading at the mid-lengths and ends. CB (Cool Beige) variants fade slightly faster than WB because ash pigment molecules are smaller and wash out more readily with water. Using a blue or purple-tinted shampoo between services prolongs the cool tone for CB clients.
Do I need to be in a salon to use DEMI Assalt Deep hair color?
DEMI Assalt Arias is a professional-grade system requiring correct developer selection, precise mixing ratios, and timed application to achieve safe, predictable results. Using it without professional training risks over-processing, uneven color, and scalp reactions from incorrect developer concentration or processing time. Professional salon application by a colorist familiar with Japanese color systems is strongly recommended.