Demi Assalt Deep Natural
DEMI Assalt Deep Natural is the permanent color line at the core of DEMI's professional Assalt system. Built for salon use, it delivers full gray coverage with a deep, natural-looking finish across a coordinated depth range. Each shade pairs a numbered depth level (D-4 through D-9) with a base tone - WB, CB, or BB - giving colorists a structured palette for predictable results on any natural base. The Arias sub-line within Assalt Deep Natural is the most stocked series, with 11+ individual shades available. The formula was developed in Japan for the professional salon market and is distributed globally through specialty beauty channels.
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Buying guide
DEMI Assalt Deep Natural: Complete Color Selection and Application Guide
DEMI Assalt Deep Natural is a structured permanent hair color system designed around a two-axis selection model: depth and base tone. This guide explains how the system works, how to choose the right combination for each client, and what to expect throughout the coloring process - from first application to fade cycle.
What Is the Assalt Deep Natural System?
Assalt is DEMI's flagship professional oxidative color family, formulated in Japan for licensed salon use. The 'Deep Natural' designation refers to a specific sub-range within Assalt focused on realistic, high-depth brown shades with superior gray coverage. Unlike fashion or highlight lines within the Assalt family, Deep Natural shades prioritize predictable tone-on-tone results and reliable performance on resistant gray hair. The Arias sub-line is the primary and most complete range within Deep Natural.
The Two-Axis Selection Model: Depth and Base
Every shade is defined by two parameters. The first is depth - a number from D-4 (darkest, very dark brown) to D-9 (lightest in this range, medium brown). The second is base tone - WB (Warm Brown), CB (Cool Brown), or BB (Blue Brown). Selecting a shade means choosing both axes: a D-7/WB will read as a warm medium brown, while a D-7/CB will appear as a cooler, more muted medium brown at the same depth. Mixing depths or bases is possible for custom results but requires strand testing.
Choosing the Right Depth Level
D-4 is suited for clients who want near-black or very dark brown results with zero warmth lift. D-5 produces a classic dark brown and is the most versatile entry point for average natural bases. D-7 and D-8 occupy the medium-brown range and show the most visible difference between WB, CB, and BB bases. D-9 is the lightest available in the Deep Natural range and is best for fine hair, previously lightened clients, or situations where a slightly lighter result is acceptable. Do not try to achieve more than two levels of lift without pre-lightening.
Choosing the Right Base Tone
WB is the most popular base and the safest choice for clients with warm natural undertones - it adds chestnut richness and fades gradually toward a warm brown. CB uses ash pigment to neutralize orange or brassy tones and is preferred for clients who have had previous color services or who want a cooler, more modern appearance. BB uses blue pigment for a deeper, more dimensional neutralization than CB, producing a slight slate-brown character that is especially effective on white or bright gray hair where ash formulas can look lavender or flat.
Developer Selection and Mixing Protocol
All Assalt shades mix 1:1 with the Assalt developer. Use 3% (10 vol) for toning without lift or for darkening. Use 6% (20 vol) for one level of lift and standard gray coverage - appropriate for most D-4 through D-7 applications. Use 9% (30 vol) when targeting two levels of lift, typically relevant for D-8 and D-9 applications on darker natural bases. Mix in a non-metallic bowl and apply immediately; the oxidative reaction begins within minutes.
Application: Wet vs. Dry Hair
Standard application is on dry hair at the roots, working through to the ends for first-time color or major shade changes. For root touch-ups, apply only to new growth for the first 30 minutes, then comb through to the ends for the final five minutes. On highly porous or previously lightened hair, slightly damp (not wet) hair can help slow down rapid uptake at the ends, producing a more even result. Never apply on dripping-wet hair, as this dilutes the developer and compromises gray coverage.
Processing Time and Temperature
Process at room temperature for 35 minutes. Heat is not recommended - elevated temperature accelerates the reaction unevenly and can intensify the blue pigment in BB shades, shifting the result away from the intended tone. A plastic processing cap (no heat) is acceptable to prevent evaporation and maintain the formula's pH consistency. Check the strand at 30 minutes for resistant gray clients before committing to a full 35.
Gray Coverage Strategy by Client Type
For clients with less than 25% gray, any base tone provides full coverage at the correct depth. For 25-75% gray, CB or BB bases are preferred to neutralize the yellow cast that often appears on white hair when warm pigments dominate. For clients who are 75-100% gray or white, BB is the most reliable base for a natural-looking result - it suppresses yellow without the greenish risk associated with heavy ash (CB) at high concentrations. Always use 6% or 9% developer with high-gray clients to ensure adequate color penetration into the cortex.
Color Fade and Maintenance Schedule
Assalt Deep Natural shades typically hold their tone for four to six weeks with proper aftercare. WB fades toward a warm golden-brown; CB and BB can develop a slight warm cast as the cool pigment disperses faster. A glossing service or color refresh at four weeks maintains vibrancy between full appointments. For root-only maintenance, touch up the regrowth at four to six weeks and comb through only if there has been notable fading in the mid-lengths and ends.
FAQ
Frequently asked questions
FAQ
Frequently asked questions
What is the DEMI Assalt color system, and how does Deep Natural fit into it?
Assalt is DEMI's core professional permanent oxidative hair color family. Within Assalt, there are several sub-lines targeting different coloring goals - fashion tones, natural tones, and highlighting. Deep Natural is the natural-tones sub-line, optimized for gray coverage and realistic brown shades. It is the most widely used Assalt range in everyday salon work.
Is DEMI Assalt Deep Natural a permanent or demi-permanent formula?
It is a permanent oxidative formula. When mixed with developer, it opens the hair cuticle and deposits color directly into the cortex. The result is permanent in the sense that it does not wash out - it only fades gradually over four to six weeks as the hair fibers are exposed to washing, UV light, and styling. Regrowth will appear at the natural base color as the hair grows.
Which depth level (D-4, D-5, D-7, D-8, or D-9) works on a dark natural base without pre-lightening?
On a natural base at level 3 or 4 (very dark brown to black), D-4 and D-5 will deposit cleanly and produce a subtle tone shift. D-7 and D-8 require pre-lightening to achieve the correct result - applying them on a very dark base without lightening will result in the shade appearing darker than labeled, and the base tone difference (WB vs CB vs BB) will be minimal. D-9 is not recommended on bases darker than level 5 without lightening.
How many DEMI Assalt Deep Natural shades are in stock on skinsli right now?
There are 11+ shades currently in stock, spanning the D-4 through D-9 depth range across WB, CB, and BB base tones. The product grid on this page reflects live inventory. Specific combinations sell out periodically - if your preferred shade is unavailable, check back as restocks happen regularly.
What is the correct color-to-developer mixing ratio for Assalt Deep Natural shades?
The standard ratio is 1:1 (equal parts color and developer). For example, 40g of color mixed with 40g of developer. Do not alter this ratio without explicit instruction from DEMI's technical guidelines, as changing the ratio affects both developer percentage and processing predictability. Only use DEMI Assalt developer - other brands' developers may not be formulated to the same pH specification.
Can I mix two different depth levels together to get an intermediate shade?
Yes, mixing adjacent depth levels is an accepted technique in the Assalt system. A 50/50 blend of D-7 and D-8 in the same base tone will produce a result close to D-7.5. Always strand test when mixing depths, and note that the resulting shade may behave differently on resistant gray - single-depth formulas provide more consistent gray coverage than blended ones.
Which DEMI Assalt Deep Natural shade gives the most reliable gray coverage?
For gray coverage, depth matters more than base tone - darker shades (D-4, D-5) provide denser pigment saturation and cover more confidently. Among base tones, BB is the most reliable on bright white or resistant gray because blue pigment neutralizes yellow without producing the greenish or flat cast that can occur with heavy ash. Use 6% or 9% developer for clients with dense gray.
In a salon setting, when do you choose WB over BB, or CB over WB?
Choose WB when the client wants warmth, vibrancy, or a chestnut brown tone, or when their natural hair has cool undertones that need balancing. Choose CB when the client has had previous color services that left an orange or brassy mid-length, or when they want a modern, muted brown. Choose BB when the client has significant white or gray and wants a natural-looking result without the greenish risk of CB on white hair - or when they want a slightly slate-brown, contemporary finish.
How does the Assalt Deep Natural formula fade over time, and is it a graceful fade?
Assalt Deep Natural fades gradually over four to six weeks. WB shades fade toward a warm golden-brown, which many clients find acceptable between appointments. CB and BB shades lose their cool or blue pigment faster (smaller pigment molecules disperse more quickly) and can shift slightly warm by week four. The fade is generally even and does not produce visible bands or patchy color loss on healthy hair.
Is it safe to use Assalt Deep Natural on hair that has been recently permed or relaxed?
DEMI recommends waiting at least two weeks after a perm or relaxer before applying color. Chemically treated hair is more porous and will absorb color faster and at higher intensity, often landing a full level darker than intended. If you do proceed within two weeks, use 3% developer, reduce processing time to 25 minutes, and do a strand test first. Combining a relaxer and permanent color in the same appointment is not recommended.
Is DEMI Assalt color officially available outside of Japan?
DEMI is a Japanese brand that has historically focused on the domestic professional market. skinsli imports authentic DEMI products for the US market. The products on this page are genuine and identical to what is sold through licensed salons in Japan.
What is the shelf life of DEMI Assalt Deep Natural color tubes, and how should they be stored?
Unopened tubes of Assalt color have a shelf life of three years from the manufacturing date. Once opened, the tube should be closed tightly after use and stored away from heat, direct light, and humidity. Any mixed color that is not immediately used must be discarded - mixed color cannot be stored and reused. An opened but unmixed tube typically remains usable for up to six months if stored correctly.