The Two Core Components
Every tattoo ink consists of two fundamental parts: pigment (solid particles that provide color) and carrier (liquid that suspends the pigment and enables injection). The ratio, quality, and compatibility of these two components determine the ink's performance — how it flows through the machine, how it deposits in skin, how it heals, and how it ages.
Think of it like paint: the pigment is the powdered colorant, and the carrier is the liquid binder that makes it usable. But unlike paint, tattoo ink must be biocompatible — safe for permanent residence within human tissue.
Pigments — The Color
Tattoo pigments are solid, insoluble particles that reflect specific wavelengths of light. They fall into two categories: organic (carbon-based molecular structures) and inorganic (mineral/metal-based).
Organic Pigments
| Class | Example Pigments | Colors | Properties |
|---|---|---|---|
| Phthalocyanine | PB 15:3, PG 7 | Blue, Green | Extremely stable, high tinting strength, excellent lightfastness |
| DPP (Diketo-pyrrolo-pyrrole) | PR 264 | Red | High stability, excellent lightfastness, low allergy risk |
| Quinacridone | PR 122, PV 19 | Magenta, Violet | Good stability, transparent, good for layering |
| Naphthol | PR 170, PR 210 | Red, Scarlet | Good stability, moderate lightfastness, REACH compliant variants |
| Monoazo | PY 74, PO 62 | Yellow, Orange | Moderate lightfastness, REACH compliant replacements for banned azo dyes |
| Dioxazine | PV 23 | Violet | Deep, strong violet. Moderate lightfastness |
Inorganic Pigments
| Pigment | CI Number | Color | Properties |
|---|---|---|---|
| Carbon Black (PBk 7) | CI 77266 | Black | Most stable tattoo pigment. Virtually permanent. Low allergy risk. |
| Titanium Dioxide (PW 6) | CI 77891 | White | Highest opacity white. Used for highlights and mixing. Non-nano form required. |
| Iron Oxides (PBr 7, PY 42, PR 101) | CI 77491/77492/77499 | Brown, Yellow Ochre, Red Oxide | Natural earth tones. Excellent stability. Used in skin tone and earth tone formulations. |
| Ultramarine (PB 29) | CI 77007 | Blue (warm) | Mineral pigment. Lower tinting strength than phthalocyanine. Warm blue tone. |
The Colour Index (CI) System
The CI system provides universal pigment identification. Every pigment has a CI number (e.g., CI 74160 for Pigment Blue 15:3) that identifies its exact chemical composition regardless of brand name or marketing terms. Two inks called "Ocean Blue" from different brands may use completely different pigments — the CI number tells you the truth. Always check CI numbers when evaluating ink quality and safety.
Carrier Solutions
The carrier is the liquid component that keeps pigment particles evenly suspended and enables smooth injection through tattoo needles. Different carriers affect ink flow, drying time, and healing.
| Carrier | Properties | Used By | REACH Status |
|---|---|---|---|
| Distilled Water | Neutral, clean, most common base. Thin consistency. | Most brands as primary base | Compliant |
| Glycerin | Thickens ink, improves pigment suspension, prevents settling. Humectant. | Most brands as secondary component | Compliant |
| Witch Hazel (Hamamelis) | Natural astringent. Dries faster on skin surface. Mild antimicrobial. | Some traditional formulations | Compliant (limits apply) |
| Propylene Glycol | Improves flow, acts as humectant, mild preservative properties. | Some brands, declining use | Compliant (concentration limits) |
| Isopropyl Alcohol | Sterilizing agent, thinner. Used sparingly. | Some formulations as minor component | Compliant (low concentration) |
| Ethanol | Solvent, antimicrobial. Dries fast. | Limited use in modern formulations | Compliant (limits apply) |
Most modern tattoo inks use a distilled water + glycerin base, sometimes with small amounts of witch hazel or isopropyl alcohol for preservation and flow enhancement. The ratio of water to glycerin determines the ink's viscosity — more glycerin = thicker ink with slower flow; more water = thinner ink with faster flow.
Preservatives & Additives
Tattoo ink must remain sterile and chemically stable over its shelf life (typically 2-5 years). This requires preservatives and stabilizers.
Common Preservatives
- Phenoxyethanol — The most widely used preservative in REACH-compliant inks. Broad-spectrum antimicrobial with good biocompatibility. Concentration limited to 1% under REACH.
- Benzisothiazolinone — Effective at very low concentrations. Some sensitivity potential. REACH restricts concentration to 0.01%.
- Rosmarinic acid — Natural preservative from rosemary. Used by some "clean" formulations. Limited efficacy compared to synthetic options.
Banned Preservatives (Under REACH)
- Formaldehyde releasers (DMDM hydantoin, Imidazolidinyl urea) — Banned due to formaldehyde release
- Methylisothiazolinone (MI) — Banned at concentrations above 0.0015%. Known contact sensitizer.
- Methylchloroisothiazolinone (MCI) — Banned. Strong sensitizer.
Other Additives
- pH adjusters — Triethanolamine or sodium hydroxide to maintain pH 6-8 range
- Surfactants — Help disperse pigment particles evenly in the carrier
- Thickening agents — Maintain consistency; prevent settling during storage
Reading Tattoo Ink Labels
Under EU REACH, tattoo ink labels must include:
- "Mixture for use in tattoos or permanent makeup" — mandatory statement
- List of ingredients — including pigment CI numbers, carrier components, and preservatives
- Batch/lot number — for traceability
- Manufacturer name and contact
- Best before date or PAO (period after opening)
- Safety warnings — allergy potential, intended use
Brand Formulation Differences
| Brand | Carrier Base | Preservative | Consistency | Philosophy |
|---|---|---|---|---|
| Eternal Ink (Apex) | Water + Glycerin | Phenoxyethanol | Medium body | Balanced performance, single-pigment where possible |
| Intenze | Water + Glycerin + Witch Hazel | Phenoxyethanol | Thin-medium | Smooth flow for detail work |
| Dynamic (Black) | Water + Glycerin | Phenoxyethanol | Medium | Optimized for black and grey wash |
| Solid Ink | Water + Glycerin | Phenoxyethanol | Medium | Single-pigment purity |
| World Famous (Limitless) | Water + Glycerin | Phenoxyethanol | Thin | Fast saturation, REACH-first design |
| Fusion Ink | Water + Glycerin | Phenoxyethanol | Medium-thick | High pigment load, bold saturation |
Safety & Biocompatibility
All ingredients in tattoo ink will reside permanently in the human body. This makes biocompatibility — the ability of a material to exist within tissue without causing harm — critically important.
What Happens to Ink in the Body
Pigment particles are deposited in the dermis where they are engulfed by macrophages (immune cells). The macrophages cannot fully digest the particles, so they hold them in place — creating the permanent tattoo. Over time, some pigment migrates to nearby lymph nodes. Studies have found tattoo pigment particles in lymph nodes of tattooed individuals, confirming systemic distribution of ink components.
Carrier components (water, glycerin, preservatives) are absorbed into the bloodstream and metabolized normally. Only the solid pigment particles remain in the skin long-term.
Safety Hierarchy by Pigment Type
- Safest: Carbon black (PBk 7), Iron oxides (PBr 7, PY 42)
- Very safe: Phthalocyanines (PB 15:3, PG 7), DPP (PR 264), TiO2 (PW 6)
- Generally safe: Quinacridones (PR 122, PV 19), Naphthols (PR 170 purified)
- Lower confidence: Monoazo yellows (PY 74) — safe per current data but less long-term research
For allergy-specific information, see: Tattoo Ink Allergies — Colors, Symptoms & Prevention.
Recommended Inks
Eternal Ink — Apex Series
Full ingredient transparency. SDS available for every color. Single-pigment formulations. REACH compliant. Industry gold standard.
Solid Ink — Single Pigment Colors
Maximum transparency — one pigment per bottle. Clean carrier formula. Full CI documentation. REACH compliant.
Dynamic — Triple Black
Pure carbon black PBk 7. Simple, clean formulation. Decades of proven safety. REACH compliant.
Frequently Asked Questions
Tattoo ink contains two main components: pigment (solid color particles) and carrier (liquid that suspends the pigment). Common pigments include carbon black (PBk 7), phthalocyanine blue/green (PB 15:3, PG 7), DPP red (PR 264), and titanium dioxide white (PW 6). Common carriers include distilled water, glycerin, and witch hazel. Preservatives like phenoxyethanol keep the ink sterile.
Modern, EU REACH-compliant tattoo inks from reputable manufacturers are considered safe for permanent use in skin. All restricted or potentially toxic ingredients have been banned or limited under REACH Entry 75. Carbon black, phthalocyanines, and DPP pigments have excellent biocompatibility profiles. The greatest historical risks came from now-banned azo pigments that could release carcinogenic aromatic amines.
The carrier is the liquid component that suspends pigment particles and enables injection. Most modern inks use distilled water + glycerin as the primary carrier. Some formulations add witch hazel (astringent) or propylene glycol (humectant). The carrier affects ink consistency, flow through needles, and drying behavior on skin.
Look for: pigment CI numbers (e.g., CI 74160 for PB 15:3), carrier ingredients, preservative type, batch number, manufacturer info, and the statement "mixture for use in tattoos or permanent makeup." Labels without CI numbers or vague ingredient lists are concerning. Reputable manufacturers provide full Safety Data Sheets on request.
Modern REACH-compliant inks must meet strict heavy metal concentration limits. Trace amounts of metals may be present as impurities in pigments, but must be below regulated thresholds: mercury below 1ppm, cadmium below 0.2ppm, lead below 1ppm. Carbon black, phthalocyanines, and DPP pigments have inherently low heavy metal content. Iron oxide pigments contain iron (not a regulated heavy metal in this context).
Phenoxyethanol is the most common preservative in REACH-compliant tattoo inks, limited to 1% concentration. It provides broad-spectrum antimicrobial protection with good biocompatibility. Formaldehyde-releasing preservatives and isothiazolinones (MI, MCI) are banned under REACH due to sensitization risks.