Vat Black 25 , CAS No.4395-53-3

CAS: 4395-53-3 Cat. No.: V1449920 Formula: C₄₅H₂₂N₂O₅ Peso molecolare: 670.67 Numero EC: 224-519-9

Storage

Store at -20°C

Shipped In

Ice chest + Ice pads

Panoramica

Vat Black 25 is a black dye.

Specifications

Condizioni di conservazione di stoccaggio

Store at -20°C

Spedito in

Ice chest + Ice pads

Questo prodotto richiede spedizione a catena fredda. I servizi di terra e altri servizi economici non sono disponibili.

Nomi e identificatori

Peso molecolare

670.67

Application Protocols

No manufacturer-validated protocols are provided for this item. The following are general, literature-style outlines for research use only.

A. Vatting/dyeing (laboratory scale):

• Prepare alkaline reducing bath: Dissolve Na2S2O4 and NaOH in deoxygenated water (e.g., N2-sparged). Heat to 50–70°C.
• Add pigment gradually with stirring; maintain inert cover. Continue until a stable leuco solution forms (bath clears/deepens depending on dye).
• Immerse substrate; allow penetration. Remove and oxidize in air or dilute H2O2. Rinse thoroughly and soap at 60–90°C.

B. Aqueous pigment dispersion:

• Combine pigment with nonionic/polymeric dispersant and deionized water (typical solids 10–30% by mass). Premix, then bead-mill to target particle size. Monitor dispersion stability (DLS/sedimentation).

C. Thin-film deposition (conceptual):

• Cast from leuco form (alkaline) onto a substrate; dry under inert atmosphere; oxidize post-deposition to lock in the pigment phase. Optimize drying to minimize cracking.

Note: Adjust concentrations, temperatures, and times to your system. Always confirm compatibility of reductants/oxidants with substrates and equipment. Follow institutional EHS policies.

Biological Roles

This product is an industrial/technical vat dye intended for research use, not a biological molecule.

• Endogenous role: None. Vat dyes are synthetic, highly conjugated organic pigments and are not known metabolites or biomolecules.
• Biochemical interactions: In general, polycyclic pigments can engage in noncovalent interactions (π–π stacking, hydrophobic effects) with biomacromolecules in vitro, but such interactions are nonspecific and system-dependent.
• Bioassays: If used as a colorant tracer in laboratory systems, validate that the dye does not interfere with optical measurements (broad visible absorption) or adsorb nonspecifically to biomaterials.
• Safety note: Avoid extrapolating any biological relevance or safety/tolerability from material science usage. No clinical or in vivo claims are made or implied for this product.

Buffer Applications

Not typically applicable. Vat Black 25 is an insoluble pigment in its oxidized form and is not used as a buffering agent.

• If incorporated into aqueous systems, buffers may be used only as media to control pH during reduction (vatting) or dispersion studies. For vatting, alkaline conditions (e.g., NaOH) are standard rather than classical biological buffers.
• Ensure buffer components do not quench the reductant or interfere with the oxidation step if you are studying redox cycling.

Green Alternatives

Consider sustainability at two levels: (1) chemistry of the dye class and (2) processing conditions.

Processing alternatives (literature-based):

• Replace sodium dithionite with greener reductants where feasible:
  • Electrochemical reduction in alkaline aqueous media can generate leuco species without sulfite/sulfate waste, reducing COD/BOD impact.
  • Glucose, ascorbate, or catalytic reducing systems (e.g., iron(II) with citrate) have been explored for vat dye reduction; efficacy and color yield vary by dye.
  • Enzymatic systems (laccase/mediator under tailored conditions) can sometimes enable oxidation steps under milder, aqueous conditions.
• Water-based dispersions using low-VOC polymeric dispersants can reduce reliance on high-boiling aprotic solvents (NMP/DMF), improving operator safety and EHS profile.

Trade-off summary:

| Option | EHS benefit | Potential trade-offs | |---|---|---| | Electrochemical vatting | Minimizes sulfite/sulfate waste | Equipment cost; dye-dependent optimization required | | Glucose/ascorbate reduction | Benign reagents, lower odor | Slower kinetics; possible bath instability | | Waterborne dispersions | Low VOC emissions | Requires dispersant selection; possible lower substrate penetration |

General recommendations:

• Optimize bath pH and temperature to improve reduction efficiency, potentially lowering reductant load.
• Implement closed-loop rinse water treatment and pigment capture to limit environmental release.
• Conduct LCA-style comparisons when selecting between vatting and dispersion routes for your application.

Pharmaceutical Uses

Not a typical pharmaceutical excipient. Vat dyes are generally used in textiles and materials science rather than in drug formulations.

• Regulatory status: No pharmacopeial monograph or excipient listing is indicated for this item. Item-specific compliance data are not provided.
• Research formulation note: If evaluated as a colorant or optical attenuator in experimental devices or diagnostic materials, confirm extractables/leachables, particle size control, and binder compatibility. Avoid use in any product intended for human or animal administration.

All usage is restricted to laboratory research contexts; no medical or clinical claims are made.

Physical Properties

Item-specific specifications are not provided in the Product Data.

• Appearance (item-specific): Not specified for this item; refer to CoA/Spec Sheet.
• Melting point / softening range (item-specific): Not specified for this item; refer to CoA/Spec Sheet.
• Boiling point (item-specific): Not applicable for pigments; thermal decomposition expected before boiling. Item-specific value not specified.
• Density (item-specific): Not specified for this item; refer to CoA/Spec Sheet.
• Solubility (item-specific): Not specified for this item; refer to CoA/Spec Sheet.
• LogP, pKa, refractive index (item-specific): Not specified for this item; refer to CoA/Spec Sheet.

General literature tendencies for vat dyes (for laboratory planning only):

• Insoluble or sparingly soluble in water and most common organic solvents in the oxidized form; forms soluble leuco salts under alkaline reducing conditions (e.g., sodium dithionite/NaOH), enabling dyeing or dispersion processing.
• High thermal stability as solids; may char or decompose rather than melt sharply due to extended conjugation.
• Often exhibit strong, broad absorption across the visible region; color depth depends on aggregation state and particle size.

Important: Do not treat literature tendencies as item specifications. For method validation, regulatory submissions, or quantitative formulation work, consult the lot-specific CoA/SDS for definitive values.

Quality and Grades

• Grade/Purity (item-specific): Not specified for this item; refer to CoA/Spec Sheet.

Context for dye and pigment grades (general information):

• Research grade vat dyes are typically controlled for identity (e.g., by IR/UV-Vis, sometimes MS), color strength, and impurity profile relevant to laboratory use. Unlike chromatographic solvents, dye “purity” may be reported as color strength or assay relative to a standard rather than a single numeric purity metric.
• Particle size distribution and dispersibility often influence application performance (e.g., for coatings or printing). These parameters may vary by lot and are typically characterized by laser diffraction or microscopy where relevant.
• Stabilizers/conditioners: Some pigment powders are supplied with trace wetting or dispersing aids. No such additives are specified for this item; refer to the CoA if such processing aids are present.

What is specific to this listing:

• Storage at -20°C and cold-chain shipping indicate a focus on preserving lot integrity and minimizing oxidative or humidity-driven changes. However, no item-specific assay, absorbance profile, or metal content is provided here.

Recommendations:

• For reproducible results in analytical or device-development contexts, request the lot CoA for spectral data (UV-Vis/NIR), residual salts/ash, moisture, and, if relevant, particle size distribution. Validate color strength in your intended matrix (e.g., alkaline leuco liquor vs. final oxidized film).

Reaction and Applications

Applications (research/materials focus):

• Vat dyeing studies: Model compound for investigating reduction/oxidation cycles of vat dyes on cellulose and other hydroxylated polymers. Useful for kinetic studies of leuco formation, diffusion, and on-substrate oxidation.
• Coatings and functional films: As a deeply colored, conjugated organic pigment, can be explored in ink, paint, or polymer matrices for optical attenuation, photothermal, or aesthetic properties. Particle size and aggregation control govern optical density and film uniformity.
• Redox chemistry education and research: Demonstrates reversible reduction to a leuco base and re-oxidation to the insoluble form; useful in teaching redox, electron transfer, and dye-substrate interactions.
• Analytical surrogates: Pigment dispersion stability and zeta potential studies, evaluating dispersants/surfactants in aqueous systems.

Practical notes (general literature):

• Vatting: Commonly achieved with sodium dithionite (Na2S2O4) and NaOH at elevated temperatures (40–80°C). Oxygen exclusion during reduction enhances leuco stability.
• Application: Apply the leuco liquor to the substrate, then oxidize (air, H2O2, or perborate) to regenerate the insoluble pigment in situ, locking it within/onto the substrate.
• Rinsing/soaping: Post-oxidation washing improves fastness by removing surface-bound, loosely held dye.
• Dispersion prep: For pigment dispersions, pre-mill with suitable dispersants; assess stability by sedimentation tests and dynamic light scattering where available.

Note: No manufacturer-validated application protocols are supplied for this item; adapt conditions from the vat dye literature and confirm on small scale.

Reaction Conditions

Conditions below are general literature guidance for vat dye processing and are not item-specific specifications.

Vatting (reduction) conditions:

• Reductant: Sodium dithionite (Na2S2O4) commonly used.
• Alkali: NaOH to achieve strongly alkaline pH (typically pH > 12).
• Temperature: 40–80°C is typical; optimize to balance dissolution rate and leuco stability.
• Atmosphere: Minimize air ingress during reduction (nitrogen cover) to prevent premature oxidation.
• Time: 15–60 min for reduction, dye-dependent.

Application and oxidation:

• Apply leuco solution to substrate (e.g., cellulose). Maintain bath temperature to sustain solubility.
• Oxidation: Expose to air or treat with mild oxidants (e.g., H2O2 or sodium perborate) to regenerate the insoluble pigment in situ.
• Post-treatment: Rinse and soap to remove unfixed surface dye and byproducts.

Dispersion preparation (if not vatting):

• Wet milling with polymeric dispersants; control particle size (often submicron) to improve stability and color strength. Use deionized water; adjust pH to match dispersant requirements.

Analytical monitoring:

• UV-Vis: Track disappearance of the oxidized chromophore upon reduction and reappearance upon oxidation.
• Redox potential: ORP/pH monitoring can guide reductant dosing.

Note: Validate all conditions at small scale; exact parameters vary between vat dyes and substrates. This item’s CoA/SDS should be consulted for any handling constraints.

Safety and Handling

Safety information specific to this item is limited in the Product Data. Always consult the SDS for authoritative guidance.

• GHS classification (item-specific): Not specified for this item; refer to SDS.
• Signal word / hazard statements / pictograms (item-specific): Not specified for this item; refer to SDS.
• Research Use: For research use only.

General laboratory precautions for vat dyes and insoluble organic pigments:

• PPE: Use lab coat, safety glasses, and appropriate chemically resistant gloves. Avoid generating or inhaling dust; use local exhaust or a fume hood during weighing and transfers.
• Incompatibilities: Although the oxidized pigment is generally stable, avoid strong oxidizers, strong reducing agents, and strong acids/bases unless performing controlled vatting/reduction. Keep away from ignition sources when handling fine powders (dust explosion potential is generally low but good housekeeping is prudent).
• First-aid overview (general):
  • Inhalation: Move to fresh air; seek medical attention if irritation persists.
  • Skin contact: Wash with soap and water; remove contaminated clothing.
  • Eye contact: Rinse cautiously with water for several minutes; seek medical attention if irritation persists.
  • Ingestion: Rinse mouth; seek medical attention.
• Environmental note: Prevent uncontrolled release to drains; pigments can be persistent in the environment. Collect spills by HEPA vacuum or damp wipe to minimize dust.

Storage and transport (from Product Data):

• Storage: Store at -20°C. Keep container tightly closed, dry, and protected from light and moisture to preserve performance characteristics.
• Shipping: Shipped in ice chest with ice pads to maintain cold chain.

Always defer to the SDS for exposure limits, toxicological data, and spill/fire-fighting procedures.

Solvent Selection

This product is a vat dye pigment, not a solvent. Solvent selection pertains to processing (reduction/vatting, dispersion, coating) rather than to chromatographic-grade solvent choice.

General solvent/media guidance (literature-based):

• Oxidized form: Typically insoluble in water and most organic solvents; process as a dispersion. High-boiling polar aprotics (e.g., NMP, DMF, DMSO) may assist in temporary swelling or dispersion but do not guarantee true molecular solubility.
• Leuco (reduced) form: Generated in alkaline aqueous media using reducing agents (commonly sodium dithionite with NaOH). The leuco form is water-soluble and can be applied to cellulosics or deposited from solution before re-oxidation.
• Dispersants and wetting agents: Nonionic surfactants or polymeric dispersants can improve stability in aqueous inks and coatings. Select dispersants compatible with intended pH and ionic strength.

Comparison snapshot (general):

| Processing route | Medium | Notes | |---|---|---| | Vatting/dyeing | Water + NaOH + Na2S2O4 | Produces soluble leuco; apply then oxidize with air/H2O2. | | Dispersion coating | Water with dispersant | Pigment remains insoluble; rely on particle-size control. | | High-T solvent processing | NMP/DMF/DMSO (limited) | May aid dispersion; risk of aggregation on cooling. |

Selection tips:

• Choose vatting conditions when you require substrate penetration (e.g., cellulose fibers) or thin-film formation from solution.
• Choose dispersion approaches when insoluble particulate colorant is acceptable or preferred for stability.
• Validate compatibility of any chosen solvent with your substrate and downstream processing (oxidation step, drying temperature).

Storage and Reconstitution

Storage (from Product Data):

• Store at -20°C. Keep container tightly closed in a dry place. Protect from light and moisture. Avoid repeated freeze–thaw of any prepared dispersions.
• Shipped in ice chest with ice pads to maintain cold conditions.

Handling tips:

• Allow container to equilibrate to ambient temperature before opening to prevent condensation. Minimize air and moisture exposure; promptly reseal after use.

Reconstitution/working preparations (general guidance):

• For vatting: Prepare fresh alkaline reducing bath (e.g., NaOH + sodium dithionite) with deoxygenated water. Introduce pigment under stirring and inert cover until a homogeneous leuco solution is obtained. Use promptly; leuco solutions are air-sensitive and best prepared just-in-time.
• For dispersions: Wet with suitable dispersant and process by milling to required particle size. Store dispersions at 4–8°C in sealed containers; monitor for sedimentation or microbial growth. Add biocide only if appropriate for your research context.

Stability notes:

• Solid pigments are generally stable when protected from heat, light, and humidity. Avoid prolonged exposure to elevated temperatures.
• Item-specific stability data (shelf life, moisture content, assay) are not specified for this item; refer to the CoA/Spec Sheet.

Always consult the SDS for additional storage compatibility and stability information.

Structure and Identity

Brief overview: Vat Black 25 is a vat dye (reduced/oxidized application cycle) supplied for research use. Item-specific structure identifiers are not provided in the Product Data.

• SKU: V1449920
• CAS: 4395-53-3
• Chemical name: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular formula (item-specific): Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight (item-specific): Not specified for this item; refer to CoA/Spec Sheet.
• SMILES: Not specified for this item; refer to CoA/Spec Sheet.
• InChIKey: Not specified for this item; refer to CoA/Spec Sheet.

Structural context (general literature for vat dyes):

• Vat dyes are typically highly conjugated, polycyclic aromatic systems bearing quinonoid carbonyl groups (often anthraquinone- or perylene-type frameworks). They are insoluble pigments that become water-soluble only upon reduction to a leuco form under alkaline conditions, then re-oxidize on the substrate to regenerate the insoluble chromophore.
• Functional features (general): multiple fused benzene rings; 1,4- or 1,9-quinone motifs; extensive π-conjugation responsible for deep black coloration (via broad absorption across the visible spectrum).
• Stereochemistry: Typically planar, rigid, polyaromatic structures; no classical stereocenters.

Note: Exact structural representation, registry synonyms, and identifiers specific to CAS 4395-53-3 are not included in the Product Data and should be confirmed via the CoA or authoritative chemical databases before structure-dependent calculations or regulatory filings.

Synthetic Utility

While Vat Black 25 is supplied as a pigment rather than as a fine-chemical building block, its polycyclic quinonoid framework (general for vat dyes) offers features of interest in synthetic and materials chemistry.

General utility (literature-based):

• Redox-active core: Quinonoid motifs can participate in reversible redox processes. In research settings, vat dyes may serve as model redox-active organic materials for studying charge transport or as electron-accepting dopants in composites.
• Surface functionalization: Pigment particles can be modified at the surface (e.g., with silanes or polymer grafts) to tailor dispersion in polymers and resins. Such modifications change processing behavior without altering the core chromophore.
• Photophysical studies: The extended π-system allows exploration of aggregation-induced spectral changes, exciton coupling, and energy dissipation mechanisms in solid matrices.

Caveats:

• As supplied, the pigment is not intended for further chemical synthesis through solution-phase reactions due to its low solubility. Any derivatization typically proceeds via heterogeneous methods or by preparing soluble leuco intermediates when feasible.
• Item-specific reactivity data and derivatization routes are not provided; consult primary literature for the specific vat dye structure corresponding to CAS 4395-53-3 before planning transformations.

Target Specificity

Not applicable. This product is a vat dye pigment and is not an antibody, ligand, or biochemical with defined biological targets.

• Antigen/epitope: Not applicable.
• Species reactivity/clone/isotype: Not applicable.