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Fixative

A fixative is a stabilizing or preservative agent used across various fields to fix, set, or preserve materials. In biology and medicine, it preserves tissues for microscopic examination; in art, it protects drawings and sketches from smudging; in perfumery, it prolongs the evaporation of fragrances; and in industry, it aids in dyeing textiles and processing photographs.^[1]^[2] The choice and application of fixatives depend on the material and purpose, balancing preservation with potential artifacts. This article covers their definitions, properties, historical development, and applications in biological, artistic, chemical, industrial, and technical contexts.

Overview

Definition and Properties

A fixative is a chemical or physical agent that stabilizes, preserves, or binds substances by preventing degradation, movement, or evaporation across various disciplines.^[1] This role involves imparting rigidity to materials while maintaining their essential characteristics, making fixatives indispensable in contexts ranging from scientific preservation to industrial binding.^[3] The term "fixative" derives from the Latin fixare, meaning "to fasten" or "to make fixed," reflecting its core function of securing elements in place.^[4] Its applications in chemistry emerged in the 17th century, including as agents for setting colors in dyeing and stabilizing compounds during early industrial processes.^[4] Fixatives generally exhibit properties such as the ability to form bonds or networks for stability, control evaporation rates in volatile applications, and adhere to surfaces without excessive alteration, though specifics vary by discipline. These agents are available in diverse physical forms, such as liquid sprays for even application, aqueous solutions for penetration, or powders for dry mixing, allowing adaptability to different uses.^[1] In biological contexts, fixation often involves mechanisms like protein denaturation to halt degradative processes, cross-linking to stabilize structures, and ionic interactions; in other fields, such as art or perfumery, it may rely on evaporation retardation or resin binding. For instance, histological fixatives exemplify scientific stabilization of biological samples, while artistic fixatives demonstrate preservation in creative media.^[5]

Historical Development

The development of fixatives traces back to the 18th century, when alum (potassium aluminum sulfate) emerged as a key mordant in textile dyeing, binding natural dyes to fibers like wool and cotton for colorfastness—a practice that dominated European industries until synthetic dyes appeared in the 1850s.^[6] In parallel, early biological preservation efforts in the 1800s utilized alcohol, particularly ethanol at concentrations around 70%, to fix and store specimens such as anatomical tissues and marine invertebrates, preventing decay and enabling long-term study despite limitations like tissue shrinkage.^[7]^[8] The 19th century brought transformative advancements, most notably the discovery of formaldehyde in 1859 by Russian chemist Alexander Mikhailovich Butlerov, who identified the compound while attempting to synthesize methylene glycol from methanol and air.^[9] By the 1890s, formaldehyde solutions (formalin) gained widespread adoption in histology after Ferdinand Blum's 1893 experiments demonstrated its superior tissue-hardening properties over alcohol, preserving cellular structures with minimal distortion and enabling detailed microscopic analysis.^[10] Earlier in the century, photography benefited from Sir John Herschel's 1839 invention of sodium thiosulfate (known as "hypo") as a fixer, which effectively removed unexposed silver halides from images, ensuring permanence in processes like daguerreotypes and calotypes.^[11] Post-1920s innovations marked the rise of synthetic fixatives, as chemical advancements enabled resins and compounds that outperformed natural alternatives in stability and versatility across applications. Synthetic musks were first developed in the late 19th century, but this era saw a significant shift in perfumery from animal-derived musks to advanced synthetic fixatives, extending scent longevity while reducing reliance on scarce natural resources. Aerosol delivery systems for art fixatives appeared in the 1940s, with products like early cellulose nitrate sprays providing uniform protection for charcoal and pastel drawings without altering hues.^[12] Since the 2000s, environmental regulations have accelerated the creation of eco-friendly fixatives, particularly through reductions in volatile organic compounds (VOCs) to curb air pollution; for instance, California's Air Resources Board lowered aerosol VOC limits by nearly 50% from the 1990s into the 2000s, spurring low-emission formulations in adhesives and coatings that maintain efficacy with diminished health and ecological risks.^[13]

Biological and Medical Applications

Histological Fixation

Histological fixation serves to preserve biological tissues by halting autolysis, putrefaction, and structural degradation, thereby maintaining cellular morphology for subsequent staining and microscopic examination.^[14] This process is essential in pathology and research to ensure that tissues retain their architectural integrity as closely as possible to their in vivo state, allowing for accurate diagnostic and scientific analysis.^[3] The primary mechanisms of fixation involve chemical reactions that stabilize tissue components, such as cross-linking proteins through aldehyde groups that form methylene bridges between amino acids like lysine and arginine.^[3] Alternative methods include dehydration and coagulation, where agents like alcohols disrupt hydrogen bonds and precipitate proteins, leading to tissue hardening without extensive cross-linking.^[15] These actions prevent enzymatic degradation and microbial growth while preserving antigenicity for immunostaining.^[14] Common fixatives include formalin, a 10% neutral buffered formaldehyde solution, which is the standard for routine light microscopy due to its broad applicability and effective protein stabilization.^[3] For electron microscopy, 2.5% buffered glutaraldehyde is preferred as it provides superior ultrastructural preservation through stronger cross-linking.^[16] Alcohols such as ethanol or methanol enable rapid fixation, often used at concentrations of 70-95% for small specimens or as co-fixatives, with fixation times ranging from hours to days depending on tissue thickness.^[15] Paraformaldehyde, at 4% concentration, serves as a polymerized form of formaldehyde for similar purposes but with reduced toxicity.^[17] Recent advances as of 2025 include non-toxic alternatives to formalin, such as zinc-based fixatives offering superior morphological preservation and glyoxal acid-free (GAF) solutions that better maintain antigenicity for immunohistochemistry while reducing health risks associated with aldehydes. Natural fixatives like honey, jaggery, and aloe vera have also shown promise in preliminary studies for sustainable tissue preservation.^[18]^[19]^[20] The fixation process typically begins with immersion, where tissues are submerged in fixative, or perfusion, where fixative is delivered via vascular routes for larger organs like the brain to ensure uniform penetration.^[21] This is followed by thorough washing in buffer to remove excess fixative. Key factors influencing efficacy include pH (optimally 7.0-7.4 to mimic physiological conditions), temperature (room temperature for faster kinetics or 4°C to slow reactions), and tissue size (thinner sections under 1 mm for optimal diffusion).^[14]^[22] Formalin offers universality and compatibility with most staining protocols but can cause tissue shrinkage and hardening, potentially distorting morphology.^[23] Its limitations include masking of antigens and formation of cross-link adducts that hinder molecular analyses.^[17] Alternatives like Bouin's solution, containing picric acid, formaldehyde, and acetic acid, minimize shrinkage and enhance nuclear staining, making it suitable for specific tissues such as gastrointestinal or endocrine samples.^[14] Formaldehyde's adoption as a fixative dates to the late 19th century, following Ferdinand Blum's 1893 observation of its tissue-preserving effects.^[24]

Embalming and Preservation

In embalming, fixatives play a crucial role in post-mortem body preservation by disinfecting tissues, dehydrating cells to inhibit bacterial growth, and facilitating cosmetic restoration to delay decomposition for public viewing during funeral practices.^[25] The primary agents are formaldehyde-based fluids, typically with an index of 20-40 indicating the percentage of formaldehyde gas, which cross-links proteins similar to principles in histological fixation but applied on a whole-body scale.^[26] Co-fixatives such as methanol, which stabilizes the solution, and glutaraldehyde, which enhances fixation in certain formulations, are commonly incorporated, alongside ancillary chemicals like dyes for restoring natural skin coloration.^[27]^[28] Key techniques involve arterial injection, where embalming fluid is introduced into major arteries like the carotid to perfuse the vascular system and displace blood, followed by cavity embalming using a trocar to aspirate and inject fluids into visceral organs.^[29]^[30] Fixation typically requires 24-48 hours for optimal tissue stabilization, during which environmental factors such as high humidity can accelerate decomposition by promoting microbial activity, thus reducing efficacy.^[31]^[32] Since the 2010s, modern variations have emerged in response to environmental regulations and health concerns, including "green embalming" that employs non-toxic alternatives like essential oil-based fluids to achieve preservation without formaldehyde.^[33] As of 2025, the embalming fluid market has grown significantly, valued at USD 6.64 billion in 2024 and projected to reach USD 12.99 billion by 2037, driven by demand for formaldehyde-free options introduced since 2020 and innovations such as AI-integrated embalming machines for efficiency and eco-friendly designs.^[34]^[35]^[36] These methods prioritize biodegradability while maintaining short-term preservation for viewing, often combined with natural burial practices to minimize ecological footprint.^[37] Health considerations for embalmers include significant exposure risks from formaldehyde, classified as a human carcinogen linked to nasopharyngeal cancer and leukemia, as well as respiratory irritation from phenolic compounds.^[38]^[39] Ethically, the environmental impact arises from phenolic compounds and formaldehyde leaching into soil and groundwater from burials, prompting shifts toward sustainable alternatives to reduce long-term pollution.^[40]^[41]

Artistic and Creative Applications

Drawing and Sketching Fixatives

Drawing and sketching fixatives serve to bind loose pigment particles from dry media, including pastels, charcoal, graphite, and colored pencils, to the paper or substrate, thereby preventing smudging, dusting, and degradation from handling or environmental factors. Workable fixatives enable artists to continue layering or revising the artwork after application by restoring surface tooth, while final fixatives provide a permanent barrier for completed pieces, often incorporating UV inhibitors for lightfastness. These products maintain the artwork's integrity without significantly altering its tactile or visual qualities when applied correctly.^[42]^[43] Common types include aerosol sprays, which are resin- or acrylic-based for even coverage, and brush-on solutions for more controlled application; natural resin variants, such as those using damar, offer traditional reworkable properties in workable formulas, while synthetic acrylics provide durable, non-yellowing finishes. Finishes vary from matte, which preserves the subtle texture of dry media, to glossy, which can enhance color vibrancy but may introduce unwanted sheen. Aerosol forms dominate modern use due to their convenience, though brush-on options allow precision on delicate surfaces.^[43]^[44]^[45] Application involves spraying or brushing in light, even layers from about 8-12 inches away to avoid clumping or uneven saturation, with each coat drying for 5-15 minutes before adding more; compatibility is key, as fixatives formulated for dry media like graphite or pastels prevent bleeding or discoloration in colored pencils. Multiple thin layers—typically 2-3 for workable types—build protection without overwhelming the substrate, and artists should test on scraps to ensure no warping occurs on thinner papers. Well-ventilated spaces are essential during aerosol use to minimize inhalation risks.^[42]^[46]^[43] Benefits include enhanced archival quality through dust repulsion and UV resistance in premium formulas, allowing long-term display without glass framing, alongside the ability to layer media buildup in multi-stage drawings. However, drawbacks encompass potential shifts in color saturation—darkening lights or muting vibrancy—subtle yellowing over decades in resin-based types, and risks of paper buckling if over-applied; workable variants may reduce overall permanence compared to finals.^[42]^[43]^[12] Notable brand examples include Krylon Workable Fixatif, an acrylic-based aerosol introduced in 1948 as one of the first protective sprays for artwork, prized for its reworkable matte finish on soft media. Post-2000 innovations feature low-odor options like SpectraFix Degas Fixative, a casein-based, non-toxic formula developed in 2007 that uses milk protein and alcohol for safe indoor application without harsh solvents.^[47]^[48]

Other Media in Art

In sculpture, fixatives serve as sealants to protect and preserve materials like clay, wax, and prosthetics, ensuring durability during creation and display. For instance, polymer clay sculptures often employ water-based sealers such as Translucent Liquid Sculpey, applied lightly with a sponge and baked to create a matte finish that prevents cracking and environmental degradation.^[49] Similarly, wax-based prosthetics in special effects (SFX) sculpture use clear liquid plastic sealers like Mehron Fixative A, which forms a flexible protective layer over modeling wax or SynWax before further application, allowing for intricate detailing without dissolution.^[50] In mixed media art, fixatives stabilize collages and airbrush applications by preventing bleeding and lifting of layered elements, particularly when combining wet and dry media. For collages incorporating painted papers, gel mediums or UV-resistant varnishes seal watercolor elements without causing runoff, maintaining vibrancy and adhesion across disparate materials.^[51] Alcohol-based fixatives, such as those with fast-evaporating solvents like isopropyl alcohol, are commonly applied over watercolor underlayers to bind pigments and inhibit smudging during subsequent airbrushing or overlay techniques.^[45] For performance art, temporary fixatives secure body paint and hair styling against movement and perspiration, enabling dynamic expressions without immediate degradation. Polymer-based sprays, including clear sealers like Mehron Fixative A, waterproof water-based body paints to simulate tattoos or prosthetics, providing short-term stability for live applications.^[52] These formulations, often reworkable, allow artists to adjust designs mid-performance while minimizing skin irritation. Since the 2000s, eco-friendly fixatives have emphasized water-based and natural formulations to align with sustainable art practices, reducing volatile organic compounds and environmental impact, with further advancements in the 2020s including Winsor & Newton's 2023 launch of a range with biodegradable packaging.^[53] Earlier products like SpectraFix, utilizing a milk casein formula developed in 2007, offer odor-free alternatives for sealing media without petroleum-derived solvents, supporting artists in adopting low-toxicity workflows.^[48] Challenges in using fixatives for other media include achieving reliable adhesion on diverse surfaces such as metal or fabric, where incompatible substrates can lead to peeling or uneven coverage.^[54] Removal for rework often requires solvent-based strippers, but workable fixatives like Krylon variants allow partial erasure with gentle rubbing, though over-application risks permanent binding.^[55]

Chemical and Industrial Applications

Perfumery and Fragrances

In perfumery, fixatives serve a critical function by slowing the evaporation of volatile top notes through blending with more stable base notes, thereby extending the overall longevity of the fragrance on the skin.^[56] This process enhances sillage—the scent trail left behind—and projection, the distance at which the fragrance can be detected, allowing the composition to evolve gradually from initial burst to lingering dry-down.^[57] By equalizing vapor pressures among fragrance molecules, fixatives stabilize the blend, preventing rapid dissipation and ensuring a balanced olfactory profile.^[58] Natural fixatives have long been derived from animal sources, such as ambergris, a waxy substance produced in the digestive system of sperm whales, which imparts a warm, marine depth but has been heavily regulated since the late 1970s under U.S. laws prohibiting the import of whale products to protect endangered species.^[59] Similarly, musk obtained from the glands of the musk deer was prized for its sensual, persistent animalic quality, though it is now largely replaced by synthetics following international protections for the species established in the 1970s and 1980s.^[60] Plant-based alternatives include benzoin, a resin with a sweet, vanilla-like aroma that adds warmth and richness, and vanilla absolutes, which provide creamy fixation without ethical concerns.^[61] Synthetic fixatives emerged prominently in the mid-20th century as ethical and sustainable options, with Iso E Super—developed in the 1970s by International Flavors & Fragrances (IFF), first synthesized in 1972 from ionone-derived structures—acting as a versatile woody-amber compound that enhances diffusion through molecular interactions that retard evaporation.^[62] Galaxolide, a polycyclic musk introduced in the late 1960s by IFF, functions similarly by encapsulating lighter scent molecules at a molecular level, prolonging their release and adding a clean, powdery tenacity developed through the 1970s and 1980s.^[63] These synthetics operate via low volatility and odor-binding mechanisms, integrating seamlessly to mimic natural effects while avoiding resource depletion.^[58] In formulation, fixatives are integrated into the perfume pyramid's base layer (typically 20-40% of the composition) to anchor lighter top notes (10-30%) and middle notes (30-60%), with perfumers adjusting ratios for desired persistence.^[64] Compatibility testing on skin is essential, involving patch tests to assess irritation from fixative concentrations, ensuring safety in final products like eau de parfum, which typically contains 15-20% fragrance oils overall.^[65] Regulatory oversight has shaped modern use, with the European Union banning or restricting nitromusks such as musk xylene (banned 2011) and musk ketone in the 2000s and 2010s due to their potential as skin allergens and environmental persistence, prompting a shift toward safer polycyclic and macrocyclic alternatives.^[66] This 20th-century transition from natural to synthetic fixatives addressed both ethical sourcing and health concerns in fragrance production.^[60] As of 2025, further regulations are emerging, including California's AB 60, which bans certain synthetic musks in cosmetics effective January 1, 2027, driven by environmental persistence concerns.^[67]

Textiles and Dyeing

In textile dyeing, fixatives, often referred to as mordants, play a crucial role in enhancing the bond between dyes and fibers through mechanisms such as chelation, where metal ions form coordination complexes with dye molecules, or precipitation, which creates insoluble dye-metal-fiber compounds that prevent color bleeding and improve wash fastness.^[68]^[69] These agents ensure dye molecules adhere permanently to the fabric substrate, thereby increasing color durability against laundering, light exposure, and abrasion.^[70] Common types of fixatives include metallic mordants such as alum (potassium aluminum sulfate), which has been utilized since ancient times to affix natural dyes to both protein and cellulosic fibers by forming stable aluminum-dye complexes.^[71]^[72] Another traditional option is tannic acid, derived from plant sources like oak galls or chestnut, which serves as an organic mordant particularly effective for natural dyes on cellulosic fabrics by precipitating dyes into tannin-fiber lakes that enhance color depth and fixation.^[73] For modern synthetic dyes, such as reactive dyes on cotton, cationic fixatives—typically polyamine-based polymers—are employed to electrostatically bind hydrolyzed dye residues, improving wet fastness without altering fabric hand.^[74]^[75] The application of fixatives involves several processes, including pre-mordanting, where the fabric is soaked in a mordant solution prior to dyeing to allow uniform metal ion attachment; simultaneous mordanting, in which the mordant is added directly to the dye bath for one-step processing; and post-mordanting, applied after dyeing to stabilize unbound dyes.^[76]^[77] pH adjustments are critical in these methods, with acidic conditions (typically pH 4-6) favored for wool to promote protonation of fiber sites and enhance mordant uptake, while neutral or slightly alkaline pH suits cellulosic fibers.^[78]^[68] Fixatives find applications in traditional techniques like batik and tie-dye, where alum or tannic acid mordants help delineate resist patterns and secure natural dyes on cotton or silk, as well as in industrial printing processes that use cationic agents to achieve precise color registration and fastness on large-scale fabric runs.^[79]^[80] Emerging eco-alternatives, such as chitosan derived from crustacean shells, have gained traction since the 2010s as biomordants for sustainable dyeing, offering biodegradable fixation for reactive and natural dyes on cotton while reducing reliance on heavy metals and improving color yield without environmental toxicity.^[81]^[82]^[83] Historically, fixatives were essential in 19th-century indigo dyeing for textiles, particularly in denim production, where post-dyeing treatments with agents like tannic acid or early synthetic stabilizers prevented crocking and ensured the blue vat dye's adhesion to cotton fibers during the Industrial Revolution's expansion of mass textile manufacturing.^[84]^[85]^[86]

Technical and Specialized Applications

Photography

In analog photography, fixatives serve to stabilize developed images by dissolving unexposed silver halide crystals, thereby preventing further reaction to light and ensuring the permanence of the latent image formed during development.^[87] This process also often involves hardening the gelatin emulsion layer to enhance physical durability and resistance to environmental factors.^[88] The primary fixing agent is sodium thiosulfate, commonly known as "hypo," first identified for its photographic utility in 1819 by astronomer Sir John F. W. Herschel, who recognized its ability to selectively remove unaltered silver salts without affecting the developed image.^[89] In 1839, William Henry Fox Talbot incorporated refinements to the calotype process, adopting hypo to fix paper negatives and positives, which marked a pivotal advancement in making silver-based photographs stable and reproducible.^[90] For faster processing, particularly in modern formulations, ammonium thiosulfate is used as an alternative, enabling shorter fixing times due to its higher solubility and reactivity with silver halides. The fixing process typically involves immersing the exposed and developed film or paper in a fixer bath for 2 to 10 minutes, with agitation to ensure even removal of unexposed halides, followed by neutralization in a stop bath or hypo clearing agent to halt residual activity and thorough washing in running water to eliminate fixer remnants.^[91] For archival purposes, fixers may include hardeners such as chrome alum, which cross-links the gelatin to prevent softening during prolonged storage or high-humidity conditions, similar in principle to cross-linking in biological fixation but tailored to emulsion stability.^[92] Following the widespread adoption of digital photography after 2000, the use of chemical fixatives in analog processes has declined sharply due to the shift toward electronic imaging, though it persists among enthusiasts in darkroom practices for artistic and experimental purposes.^[93] In digital workflows, equivalents include software algorithms for image stabilization and noise reduction, which metaphorically "fix" pixel data post-capture without chemical intervention.^[91]

Nuclear and Environmental Uses

In nuclear applications, while cementation remains the most common method for immobilizing low- and intermediate-level radioactive waste, polymer-based fixatives such as epoxy resins have been utilized since the 1970s to encapsulate radionuclides, thereby immobilizing radioactive waste and preventing leaching into the environment during long-term storage.^[94] These materials provide a robust barrier due to their chemical resistance, low shrinkage, and ability to withstand radiation, making them suitable for packaging low- and intermediate-level wastes.^[94] Epoxy encapsulation has been particularly effective in converting liquid or solid radioactive residues into stable monolithic forms, reducing the risk of dispersion in disposal facilities.^[95] In environmental contexts, fixatives like phosphate compounds play a critical role in immobilizing heavy metals in contaminated soils, especially following the enactment of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) in 1980, which mandated remediation of hazardous sites.^[96] For instance, phosphates react with lead to form insoluble pyromorphite minerals, significantly lowering bioaccessibility and mobility in soil, as demonstrated in treatments of lead-impacted urban sites.^[97] This in situ stabilization approach minimizes the need for excavation, offering a cost-effective method compliant with EPA guidelines for contaminated land management.^[98] The primary mechanisms of these fixatives include adsorption, where contaminants bind to the surface of materials like zeolites; encapsulation, which physically encloses radionuclides or metals within a polymer matrix; and vitrification, converting waste into a glass-like solid for enhanced durability.^[99] Leachability is assessed using standardized EPA methods, such as the Toxicity Characteristic Leaching Procedure (TCLP), to ensure minimal release under simulated environmental conditions over extended periods.^[100] Notable examples include the 1986 Chernobyl cleanup, where zeolite-based fixatives, primarily clinoptilolite, were applied on a massive scale—approximately 500,000 tons—to adsorb cesium and strontium from contaminated soils and water, mitigating widespread radioactive dispersion.^[101] In modern groundwater remediation, nanomaterials such as nano-zero-valent iron (nZVI) coated with cellulose serve as fixatives to immobilize heavy metals like chromium and lead, achieving high removal efficiencies through reductive precipitation and adsorption in contaminated aquifers.^[102] Key challenges in these applications involve ensuring long-term stability over centuries, as fixatives must resist degradation from radiation, weathering, and geochemical changes, with durability assessments evolving since the 1980s to predict performance in geological repositories.^[103] Regulatory compliance adds complexity, requiring adherence to stringent standards from agencies like the EPA and NRC to verify containment efficacy and minimize environmental risks during waste handling and disposal.^[104]

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Mehron Fixative "A" Sealer - HollyNorth
In stockMehron Fixative "A" can be used to seal intricate water based paint designs, making them waterproof so they appear as tattoos.
[48]
Draw & Write - Tools and Accessories - Fixatives - Wet Paint
Free delivery over $99 60-day returnsSpectrafix Odor-Free Pastel Fixative - Milk Casein Formula 12oz · $16.95 ; Lascaux Artist Colors Fixative 10 Oz Spray - Domestic U.S. Only! · $59.95 · $41.97.<|separator|>
[49]
Painting with Oils on Non-Porous Substrates | Just Paint
Dec 10, 2020 · We wanted to create some initial testing focused on how well oil paints adhere to these and other non-porous substrates without any ground preparation.
[50]
How to Use Fixative, Varnish, and Cold Wax for Mixed Media Projects
Jun 25, 2024 · I typically go for Krylon Workable Fixative—a bit less “green”, but incredibly efficient. A single layer of spray (preferably outside) can seal ...
[51]
Fragrance Fixatives – The Key To Long Lasting Fragrances
Feb 20, 2023 · Fragrance fixatives are natural substances that hold and 'fix' a fragrance, making it last longer on the skin by equalizing vapor pressures.
[52]
https://hollynorth.com/product/fixative-a-sealer/
[53]
https://datahorizzonresearch.com/drawing-fixative-market-44601
[54]
Ambergris | Perfumer & Flavorist
Apr 6, 2016 · Because of a late 1970s US law prohibiting the importing of ambergris or any whale products into the US, natural ambergris is no longer used in ...
[55]
https://catherinerains.com/how-to-finish-your-art/
[56]
https://www.alphaaromatics.com/blog/fragrance-fixatives/
[57]
Synthetic terpenoids in the world of fragrances: Iso E Super ... - NIH
Oct 31, 2019 · This short review describes the story of the most successful synthetic fragrance ever which is called Iso E Super ® as it is an ingredient in a large number of ...
[58]
https://www.packamor.com/blogs/fragrance-foundry/how-to-make-your-perfume-last-longer-the-truth-about-fixatives
[59]
https://www.perfumerflavorist.com/fragrance/ingredients/article/21860803/ambergris
[60]
A Perfumer's Simplified Guide To The Fragrance Pyramid
Feb 7, 2023 · The fragrance pyramid, or triangle, represents scent formulations with head, heart, and dry down notes. It has three layers of notes that blend ...
[61]
Synthetic Musks - Safe Cosmetics
Environmental concerns motivated Japan to ban musk xylene and other nitro-musks in the 1980s. ... EU regulation follows fragrance industry's voluntary global ban.
[62]
Bio-mordants: a review - PMC - PubMed Central
Because some natural dyes have little to no affinity for textiles, heavy metal salts are used as mordants to fix the color and provide color fastness. The ...
[63]
(PDF) Role of mordants in natural fabric dyeing and their ...
Dec 23, 2024 · This review article explores the use of mordants in textile dyeing processes, encompassing both traditional metal mordants and emerging bio-mordants.
[64]
[PDF] Advancements in Sustainable Natural Dyes for Textile Applications
Aug 8, 2023 · Mordants are usually metal salts (e.g., aluminum, iron, copper, tin, and chrome) used to fix a dye to a fabric; however, the most used mordants ...
[65]
[PDF] comparison of aluminum mordants on colorfastness of natural - K-REx
May 14, 2010 · Many salts, called mordants, are used to help affix natural dyes to fabrics, called mordants, but the most common is potassium aluminum sulfate.
[66]
Alum Mineral and the Importance for Textile Dyeing - ResearchGate
Aug 6, 2025 · The mordants used are mineral salts such as Alum (potassium and aluminum bisulfate), ferrous sulfate and copper sulphate or also organic ...
[67]
[PDF] ABSTRACT YI, DING. A Comparison of Mordant and Natural Dyes in ...
Regarding the dyeing of cotton or wool fabrics, tannic acid forms a color lake with dye inside the fiber which fixes dye to fibers more strongly (17; 26).
[68]
[PDF] Cationic dye fixing agents on cotton fabric - Sarex
Nov 2, 2023 · The cationic after-treatment auxiliaries or the cationic dye fixing agents for cotton fabrics are based on various chemistries viz., polyamine, ...
[69]
Cationic Dye Fixing Agents: Revolutionizing Color Fastness in ...
Sep 12, 2025 · They provide a robust solution for achieving excellent color fastness, particularly in challenging applications involving reactive dyes. By ...
[70]
[PDF] Dyeing Techniques and Mordanting Methods Applied in Natural ...
According to several reseaches, whether pre-mordanted or simultaneous mordanted or post-mordanted, the colour depends not only on the natural colourant but ...
[71]
https://krex.k-state.edu/bitstreams/91a085d7-849a-4731-ac9b-8fe5f4195945/download
[72]
(PDF) Effect of mordants and mordanting methods on the dyeing ...
pH of dye bath before and after dyeing varied significantly among different mordants used. Percentage dye uptake due to various mordant was significantly (P < ...
[73]
Batik Printing: An Overview, Dyeing Method, Its History and Application
Feb 25, 2023 · Mordants - Some natural dyes require the use of a mordant to help the dye adhere to the fabric. Common mordants include alum, iron, and tannic ...
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Printing with Natural Dyes – Textile colouration and finishes
A mordant is an element which aids the chemical reaction that takes place between the dye and the fibre, so that the dye is absorbed . Thesecompounds bind the ...
[75]
Sustainable Natural Textile Dyeing Using Chitosan and Its Derivatives
Chitosan, a natural resource, is a sustainable alternative to toxic metal mordants in natural textile dyeing, acting as a biomordant.
[76]
Sustainable Chitosan Biomordant Dyeing and Functionalization of ...
Dec 7, 2023 · Chitosan mordanting improved the bending rigidity and compression recovery of the cotton fabric, but it also reduced the handle and flexibility ...<|separator|>
[77]
Chitosan Nanoparticles as Bioactive Vehicles for Textile Dyeing - NIH
Nov 9, 2022 · Chitosan nanoparticles (NTDs) are used for a one-step textile dyeing and functionalization method, effectively dyeing cotton and forming ...
[78]
Early Indigo Dyeing & Printing Methods - Online Quilt Magazine.com
Jun 26, 2024 · This article from Kimberly Wulfert explores some of the early indigo dyeing practices, and how fabrics were printed.
[79]
Indigo Gives America the Blues | International Quilt Museum
Because it does not naturally dissolve in water or adhere to textile fibers, dyers had to develop complex methods for permanently fixing the indigo to fabric.
[80]
Process for improving washfastness of indigo-dyed fabrics
Dyes are fixed in an indigo-dyed cellulosic fabric, such as denim, in order to improve its washfastness, by applying an aqueous solution of a fixative ...
[81]
Basic B&W Chemistry
This is the chemical job of the "fixer." Since silver halides are all water insoluble, they have to be removed by chemical reaction. Sodium thiosulfate and ...Missing: analog | Show results with:analog
[82]
Properties and Stability of Gelatin Layers in Photographic Materials
Gelatin withstands dry heat at 100°C for several weeks, but a combination of heat and moisture may cause degradation to form soluble break-down products.<|control11|><|separator|>
[83]
To fix or not to fix? – Sir John Herschel's question
Jan 22, 2016 · ... (sodium thiosulphate), the fixer essential to making silver-based photographs permanent. Herschel did not invent hypo, but as early as 1819 ...
[84]
Chapter 9. The Albumen & Salted Paper Book
The discovery of the fixative properties of sodium thiosulfate (or "hyposulfite of soda" as it was known then) was made in 1839 by Sir John F. W. Herschel.
[85]
Beginners Guide to Processing Film - Ilford Photo %
Mar 30, 2017 · After 10 seconds, pour it out. The time in the stop bath is not critical but it must be at least 10 seconds. Next pour in the ILFORD RAPID FIXER ...
[86]
Chrome alum vs hardening fixer? | Photrio.com Photography Forums
Jan 2, 2006 · Chrome alum is used when processing at high temperatures or when a bit more hardening is desired. A chrome alum stop bath may help prevent swelling and damage ...Chrome alum - Photrio.com Photography ForumsStrengthening Film Emulsion | Photrio.com Photography ForumsMore results from www.photrio.com
[87]
Why Film Photography's Revival Refuses to Die: Insights for 2025
Aug 20, 2025 · Global production capacity has fallen hard since the 2000s, and prices keep casual shooters on the sidelines. Heaton admits what many of us ...
[88]
[PDF] moderated Nuclear Reactors Decommissioning - CET vol 99
Fixatives in nuclear industry were first used in 1950s to bind ... Management of Radioactive Waste. Containing Graphite: Overview of Methods ...<|control11|><|separator|>
[89]
Monte Carlo simulations of radioactive waste embedded into polymer
Epoxy resins have high chemical and corrosion resistance, outstanding adhesion properties, low shrinkage upon cure (Fried, 2003) and high radiation ...
[90]
[PDF] Polymer Encapsulation of Nuclear Waste: Alternatives to Grout
Advantages. – Flexible: Formulations can be easily tailored to individual wastes if required. – Compatible with most wastes.
[91]
Stabilization/Solidification of CERCLA and RCRA Wastes-Physical ...
1 Freezing & thawing test of solid waste 4.6. · 2 Wetting & drying test of solid wastes 4.6. · 3 Interpretation & application of results of durability tests 5.
[92]
Lead stabilization by phosphate amendments in soil impacted by ...
Overall, the addition of soluble phosphate to these soils appears to be an effective approach for immobilizing Pb and reducing the associated bio-accessibility.Missing: fixatives CERCLA 1980
[93]
Amending Soils With Phosphate As Means To Mitigate Soil Lead ...
Oct 23, 2013 · These remediation strategies may be less expensive and far less disruptive than excavation and removal of soil. This review evaluates evidence ...Missing: fixatives | Show results with:fixatives
[94]
The radioactive waste management - State of the art and emerging ...
Nov 5, 2025 · The main three mechanisms for solidification of waste by cement are physical encapsulation, physical adsorption and chemical fixation and their ...
[95]
Handbook: Vitrification Technologies for Treatment of Hazardous ...
A Review of Leaching Test Methods and the Leachability of Various Solid Media Contain- ing Radioactive Wastes. BNWL-1765, Pacific North- west Laboratory ...
[96]
CHERNOBYL DISASTER, UA – 1986 - ZEOCEM
Jan 24, 2017 · To eliminate the contamination about 500 000 tons of zeolite / clinoptilolite mainly / from various deposits has been used. The clinoptilolite ...
[97]
Nanomaterials offer a solution for groundwater remediation
Oct 21, 2024 · A group of Indian researchers used cellulose-coated nano-zerovalent iron particles to successfully clean up chromium-contaminated water.Missing: modern fixatives
[98]
Forty years of durability assessment of nuclear waste glass ... - Nature
Dec 20, 2021 · Standard methods to assess the durability of vitrified radioactive waste were first developed in the 1980's and, over the last 40 years, have evolved to yield ...
[99]
[PDF] Overcoming Barriers in the Implementation of Environmental ...
This publication discusses overcoming barriers in environmental remediation projects, including risk assessment, hazardous waste management, and radiation ...Missing: fixatives | Show results with:fixatives