ATBC (Acetyl Tributyl Citrate): Properties, Uses in Plastics and Regulatory Status

ATBC (acetyl tributyl citrate, CAS 77-90-7) is an acetylated citrate ester used as a non-phthalate plasticizer in the plastics applications where migration matters most: PVC toys, food cling film, medical PVC and PLA film. Citric acid forms the backbone of the molecule, so suppliers market the ATBC plasticizer as the bio-based answer to phthalates, which raises the question of what its regulatory file actually says.

The file records four positions. ATBC is registered under REACH (Regulation (EC) No 1907/2006), is absent from the REACH Candidate List of Substances of Very High Concern, carries no harmonised classification under the CLP Regulation (EC) No 1272/2008, and is authorised for EU food-contact plastics as FCM substance 138 under Regulation (EU) No 10/2011, with no individual specific migration limit but with group restriction 32, which caps the sum of 22 listed plasticizers at 60 mg/kg of food (status 23 September 2026). In the United States it is a prior-sanctioned plasticizer under 21 CFR 181.27, it is on the TSCA Inventory with an active commercial status, and it is not on the California Proposition 65 list (OEHHA list edition of 31 July 2026). ATBC is one of 56 plasticizer pages in our directory of plastic additives, each carrying the same identity, dosage and regulatory fields.

This page holds the data-sheet view and the compliance view in one place: the identity that separates ATBC from its un-acetylated parent TBC, the mechanism that makes one citrate ester work in both PVC and PLA, the physical constants recorded by PubChem, the 10 to 35 wt% band in flexible PVC and the 15 wt% reference level in PLA film, 4 application areas, the performance values that exist and the ones that do not, a dated regulatory matrix, the comparison with DOTP, DINCH, TBC, TEC and DEHP, and the trade names a buyer can source.

Table T1. ATBC identity card.

Footnote: identity, physical and classification data from PubChem CID 6505; regulatory entries from ECHA registration dossier 13143 and the EU and US legal texts cited in each section. Status as of 23 September 2026.

What Is ATBC (Acetyl Tributyl Citrate)?#

ATBC is the tributyl ester of citric acid with the free hydroxyl group acetylated, and it acts as a primary plasticizer: it is compatible enough with PVC to be used as the sole plasticizer. Citric acid carries three carboxyl groups and one tertiary hydroxyl group: the three carboxyl groups are esterified with n-butanol to give the triester, and the acetylated hydroxyl group carries the acetyl cap that the prefix in the name records. The result has the formula C20H34O8 and a molecular weight of 402.5 g/mol, and the synonym tributyl 2-acetylcitrate encodes both structural parts in one string. Which substances, then, does the name ATBC actually cover?

The functional half of the answer comes from a standard. ASTM D883 defines a plasticizer as a substance incorporated into a plastic or elastomer to increase its flexibility, workability or distensibility, and a primary plasticizer does that alone, unlike a secondary plasticizer or extender. The classes that meet the primary test include ortho-phthalates, terephthalates, cyclohexanoates such as DINCH, trimellitates and citrates, and the hub on plasticizers for plastics compares all 14 of them. ATBC holds the sensitive-application slot, the one a compounder reaches for when the article is a toy, a cling film or a medical part.

What is another name for acetyl tributyl citrate?#

Acetyl tributyl citrate is also written tributyl 2-acetylcitrate or tributyl O-acetylcitrate, abbreviated ATBC, and sold under the trade names Citroflex A-4, Uniplex 84 and Estaflex ATC. Regulators use a fourth form: Annex I of Regulation (EU) No 10/2011 lists it as tri-n-butyl acetyl citrate at FCM 138, and supplier literature uses acetyl tri-n-butyl citrate. All six names describe one substance, CAS 77-90-7.

Is ATBC a phthalate?#

No: ATBC is an ester of citric acid, not of phthalic acid, so none of the phthalate rules apply to it, including REACH Annex XVII entries 51 and 52. Entry 51 covers DEHP, DBP, BBP and DIBP at 0.1 % by weight in all plasticised articles since 7 July 2020, and entry 52 covers DINP, DIDP and DNOP in mouthable toys and childcare articles. Neither entry names a citrate ester.

The precise label matters when a specification is written. ATBC belongs to the tricarboxylic ester group and shares no structural element with the ortho-phthalates beyond being an ester, so the plain term non-phthalate is accurate here. ATBC belongs to the non-phthalate plasticizers, the group that no phthalate restriction reaches, and its position is a matter of chemical class rather than of a derogation.

What is tributyl citrate, and how does ATBC differ from it?#

Tributyl citrate (TBC, CAS 77-94-1) is the un-acetylated citrate triester, and ATBC is TBC with its free hydroxyl group capped by an acetyl group, which raises the molecular weight from 360.4 to 402.5 g/mol. TBC carries the formula C18H32O7 and EC number 201-071-2, and plasticises PVC and nitrocellulose in the same 10 to 35 wt% band the ECHA use mapping records for ATBC.

The regulatory files diverge more than the structures do. ATBC is FCM substance 138 in Annex I of Regulation (EU) No 10/2011, while TBC (tributyl citrate) is not listed in Annex I in the consolidated text of 14 July 2026, and the ECHA notifications for TBC report H318, causes serious eye damage, where those for ATBC report no classification.

Is ATBC a bio-based plasticizer?#

ATBC is built on citric acid, which industry produces by fermentation, so suppliers sell it as a bio-based plasticizer, but a bio-based content figure only counts when it is measured by radiocarbon under ASTM D6866. Bio-based means the carbon comes from biomass rather than fossil feedstock, and it is not the same property as biodegradability. No ASTM D6866 bio-based content value for ATBC, and no statement about the origin of the n-butanol, is recorded here, so this page prints no percentage. ATBC is marketed with the other bio-based plasticizers, where the measured claim and the marketing claim often differ.

How Does ATBC Plasticize PVC and PLA?#

ATBC plasticizes by placing its three butyl ester arms between the polymer chains, weakening the dipole and van der Waals forces that hold them together and lowering the glass transition temperature. Chain segments gain rotational freedom, the modulus falls, and the compound turns flexible at room temperature. Why does the same molecule work in both PVC and PLA? Polarity is the matching criterion, and citrates sit high on it: in the Hallstar polarity ranking of ester plasticizers, the tricarboxylic esters rank above phthalates, trimellitates and aliphatic diesters. That polarity suits the C-Cl dipole of PVC and the polar ester backbone of PLA alike, and compatibility holds when the solubility parameters of polymer and plasticizer lie within ±1.5 (cal/cm3)^0.5 of each other.

The 4 classic plasticization theories that describe this behaviour are listed below.

• Lubricity theory, which treats the plasticizer as a lubricant between chains that slide past one another.
• Gel theory, which treats the plastic as a three-dimensional gel whose contact points the plasticizer breaks.
• Free volume theory, which treats plasticization as an increase in free volume and underpins the Fox equation used to predict the glass transition temperature of a plasticised blend.
• Mechanistic theory, which describes a dynamic solvation and desolvation equilibrium between plasticizer and polymer.

The free-volume route is the one with measured ATBC support. In the 2018 review of PLA plasticization published in RSC Advances, the glass transition depression produced by ATBC in PLA follows Fox's law, and no phase separation appears up to 17 wt%. The four theories are explained with solubility parameters on how plasticizers work. No ATBC-specific solubility parameter, glass-transition depression coefficient or PVC gelation temperature is recorded here, so this page names the models and gives no PVC numbers. Citrates sit on the primary side of the split described under primary vs secondary plasticizers.

What Are the Physical and Chemical Properties of ATBC?#

The physical constants recorded for acetyl tributyl citrate are set out below, each with the condition at which it was measured.

Table T2. ATBC physical and chemical properties.

ATBC is a colourless liquid with a mild sweet odour, a melting point of -80 °C (-112 °F) and a density of 1.046 at 25 °C (77 °F), which places it among the denser plasticizers in use. A melting point 80 degrees below zero means the acetyl tributyl citrate density figures on a supplier sheet describe a liquid across the whole storage and handling range, and the substance is classified as combustible rather than flammable.

Two constants in the record conflict, and both are printed here rather than averaged. Published flash points for ATBC differ by test method: our source library records 204 °C (399.2 °F) and 113 °C (235.4 °F) closed cup, so take the value from the supplier's safety data sheet for the grade you buy. Boiling points are quoted at different pressures, 331 °C (627.8 °F) at 732 mm Hg and 172 to 174 °C (341.6 to 345.2 °F) at 1 mm Hg, and a second value of 326 °C appears without a stated purity, so always compare pressures before comparing sheets.

Which Polymers Use ATBC, and at What Dosage?#

ATBC is used at 10 to 35 wt% in flexible PVC and at about 15 wt% in PLA film, the two polymer systems where sourced dosage figures exist. The PVC band comes from the ECHA use mapping reproduced in PubChem CID 6505, which records concentrations in the finished compound rather than a supplier recommendation. Cellulosics and PVdC are recorded as ATBC substrates without a quantified level.

How do these weight percentages convert to phr? The conversion is arithmetic: wt% equals phr of the component divided by the total phr of the formulation, multiplied by 100. A compound of 100 phr PVC resin plus 30 phr ATBC totals 130 phr, so the ATBC content is 30 divided by 130 multiplied by 100, or 23.1 wt%. Real compounds also carry heat stabilizers, lubricants and fillers, so the divisor is the full formulation total. PVC recipes give ATBC in PHR (parts per hundred resin), which converts to weight percent with the full formulation total.

Table T3. ATBC dosage by polymer.

ATBC in flexible PVC compounds#

ATBC works as a primary plasticizer in flexible PVC at 10 to 35 wt%, which covers the whole soft-PVC hardness range rather than a co-plasticizer niche. A flexible PVC compound carries 5 to 65 wt% total plasticizer and lands between Shore A 50 and Shore A 90 depending on that loading, so an ATBC level of 10 to 35 wt% reaches from a semi-rigid sheet to a soft toy part.

Being a primary plasticizer, ATBC can carry a compound alone. The PVC uses it serves are the sensitive ones, toys, food film and medical parts, rather than wire, cable and flooring. No substitution factor for ATBC against DEHP or DOTP is recorded here, so no phr-for-phr replacement ratio is published. ATBC competes with DINCH, DEHT and ESBO across the plasticizers for PVC range.

ATBC in PLA and other biopolymers#

ATBC is the most studied PLA plasticizer: in the 2018 RSC Advances review of PLA plasticization it stays miscible with PLA up to about 50 wt%, with no phase separation up to 17 wt%, and at 13 wt% and above it raised elongation at break above 300 %. Unplasticised PLA has a glass transition temperature of 60 to 65 °C (140 to 149 °F) and a melting range of 130 to 180 °C (266 to 356 °F), and it fails in a brittle mode, so elongation is the property a plasticizer is added to change.

The loading used in current film work sits well below the miscibility ceiling. Gonzalez-Serrud and colleagues reported in Polymers in 2026 that 15 wt% ATBC is the reference plasticizer level in recycled-PLA films, inside the 17 wt% no-phase-separation window the RSC Advances review identified. Citrates, PEG and triacetin are compared on plasticizers for PLA.

ATBC in cellulosics and PVdC#

ATBC also plasticizes cellulosics and PVdC, although no dosage figure for either is recorded in our source library, and the cellulose-acetate plasticizers that are quantified here are triacetin, DEP and triethyl citrate. The PVC band of 10 to 35 wt% does not transfer to those polymers, so a cellulosic or PVdC formulation is developed against its own solubility and migration tests. Triacetin, DEP and TEC are the quantified options on plasticizers for cellulose acetate.

What Is ATBC Used For? 4 Applications in Plastics#

ATBC is used in 4 main plastics applications: toys and childcare articles, food cling film, medical PVC, and PLA film. The 4 application areas are listed below.

• Toys and childcare articles, where ATBC replaced restricted ortho-phthalates in soft PVC.
• Food cling film and other food-contact packaging, governed by group restriction 32.
• Medical devices and pharmaceutical films made from plasticised PVC.
• PLA film and compostable packaging, where ATBC is the reference plasticizer of the research literature.

Toys and childcare articles#

ATBC is one of 5 plasticizers that replaced restricted phthalates in PVC toys, alongside DEHT, TXIB, DINCH and ESBO, in the market survey Helene Wiesinger and colleagues at ETH Zürich published in Environmental Science & Technology in 2024. The survey analyses products on sale rather than permitted substances, so it records what compounders used after Annex XVII entries 51 and 52 closed the phthalate route.

The same survey found restricted phthalates still present in 11 of 118 Swiss samples, 89 of 700 EU samples and 17 of 49 New Zealand samples of PVC toys, mainly through recycled content carried into new parts. Under US law, the 16 CFR 1307 list of restricted phthalates does not name ATBC or any other citrate ester. Which plasticizers each jurisdiction allows is tabulated on plasticizers for toys.

Food cling film and food-contact packaging#

ATBC is used in PVC cling film, where its EU status is set by group restriction 32: the sum of 22 listed plasticizers, ATBC among them, must not migrate above 60 mg/kg of food. Group 32 gathers FCM substances that share one ceiling: ATBC as FCM 138, TEC as FCM 140, DEHP as FCM 283, ESBO as FCM 532, DINP as FCM 728, DIDP as FCM 729, DINCH as FCM 775, COMGHA as FCM 783 and DEHT as FCM 798.

A second ceiling applies on top of the group limit. The overall migration limit of Regulation (EU) No 10/2011 is 10 mg/dm2, expressed as 60 mg/kg for articles intended for infants and young children, whatever the plasticizer package contains. No ATBC dosage for cling film is recorded here, so no film loading is printed. The full film package, from heat stabilizer to antifog and slip agent, is on additives for food packaging.

Medical devices and pharmaceutical films#

ATBC is used in medical PVC, but it is not one of the 4 DEHP alternatives the European Pharmacopoeia names for PVC blood containers: those are DINCH, BTHC, TOTM and DEHT. DEHP-free PVC formulations are set out on additives for medical plastics, where plasticizer choice follows extraction into blood components and sterilisation stability rather than food-contact rules.

Within the citrate class the blood-bag role belongs to BTHC, butyryl trihexyl citrate, used in the PL 2209 platelet-storage container. No ATBC medical-device dosage, USP class or ISO 10993 result is recorded here. The four Ph. Eur. alternatives are compared on plasticizers for medical devices.

PLA film and compostable packaging#

ATBC is the reference plasticizer in PLA film work, used at about 15 wt% in the recycled-PLA films Gonzalez-Serrud and colleagues reported in Polymers in 2026. Compostable packaging built on PLA is assessed against EN 13432, and industrial composting at 58 °C (136.4 °F) decomposes about half the material in 60 days.

Migration is the limit of that use. Höglund, Hakkarainen and Albertsson at KTH Royal Institute of Technology reported in Biomacromolecules in 2010 that ATBC migrates into water immediately on immersion and then hydrolyses, so an aqueous contact phase can strip plasticizer from a PLA film early rather than gradually. Plasticizers are one of 4 additive families in the package on additives for PLA (polylactic acid).

How Does ATBC Perform in Plastics?#

The one performance property quantified for ATBC in the literature is elongation at break in PLA, which rose above 300 % at 13 wt% and above in the 2018 RSC Advances review. Every other indicator a formulator compares, plasticizer efficiency, volatility, extraction resistance and low-temperature flexibility, is unrecorded for this substance, so this page names the test methods instead of inventing values. Diffusion, exudation and extraction are separated on additive migration in plastics.

Does ATBC hold up against migration and extraction? One measured result exists. Höglund, Hakkarainen and Albertsson reported in Biomacromolecules in 2010 that ATBC migrates into water immediately on immersion and then hydrolyses, a two-step behaviour a single end-point number would hide. The standard methods are ASTM D1203 Methods A and B and ISO 176 for volatility, ISO 177 for migration, and ASTM D1239 for resistance to extraction.

Table T4. ATBC performance indicators and the methods that measure them.

Four of the eight rows carry no value, which is the state of the public record for this substance rather than an omission. EN 1186 and EN 13130 simulants are explained under migration testing.

How Does ATBC Interact with Other Plasticizers and Additives?#

ATBC is normally used with a second ester and a stabilizer package rather than alone: the toy and food-film compounds that carry it also carry ESBO, DINCH, DEHT or TXIB. The 3 interaction patterns recorded for ATBC are listed below.

• Epoxidised esters, above all ESBO, which acts as a co-stabilizer at 1 to 2 wt% and as a main plasticizer at 25 to 45 wt% according to Czogała and colleagues in 2021, and which shares group restriction 32 with ATBC.
• Non-phthalate co-plasticizers, DINCH and DEHT, which appear beside ATBC in the same toy compounds in the Wiesinger 2024 survey and which also sit inside group restriction 32.
• Fast-fusing specialty esters, TXIB, which is FCM 497 with an individual specific migration limit of 5 mg/kg and is restricted in EU food contact to single-use gloves.

Blending does not buy migration headroom. ESBO (epoxidized soybean oil) acts as a co-stabilizer at 1 to 2 wt% and shares group restriction 32 with ATBC, so a compound containing ATBC, ESBO and DINCH is measured against one ceiling of 60 mg/kg for the sum of all three. Compatibility between blended esters follows the resin rule, a solubility-parameter difference within ±1.5 (cal/cm3)^0.5.

What Is the Regulatory Status of ATBC?#

ATBC is REACH-registered, is not a Substance of Very High Concern, is not restricted under REACH Annex XVII, is authorised for EU food-contact plastics as FCM substance 138 under group restriction 32, and carries a United States prior sanction under 21 CFR 181.27 (status 23 September 2026). The full matrix is set out below.

Table T5. ATBC regulatory matrix, status 23 September 2026.

The two US cells that were open are now filled: ATBC is on the TSCA Inventory with an active commercial status and no risk evaluation under way, and it is not on the California Proposition 65 list as of the OEHHA list edition of 31 July 2026. Entries 51 and 52 are explained on REACH Annex XVII restrictions.

Is ATBC REACH registered, and is it an SVHC?#

Yes, ATBC is registered under REACH (Regulation (EC) No 1907/2006), and no, it is not a Substance of Very High Concern: it is absent from the Candidate List as of 23 September 2026. The registration dossier is ECHA dossier 13143 and the registration is active; the tonnage band is not captured here, so no volume figure is printed.

Candidate List status divides ATBC from the substance it replaces. DEHP has been on the SVHC Candidate List since 28 October 2008; ATBC has never been added, and it appears on neither Annex XIV nor Annex XVII.

Is ATBC allowed in food-contact plastics?#

Yes, in the EU: ATBC is listed in Annex I of Regulation (EU) No 10/2011 as FCM substance 138, under the name tri-n-butyl acetyl citrate, with no individual specific migration limit but with group restriction 32, which caps the sum of 22 listed plasticizers at 60 mg/kg. The reference number is 93760, and the overall migration limit of 10 mg/dm2, expressed as 60 mg/kg for articles intended for infants, applies on top of it. Group restriction 32 and the overall migration limit are explained on EU 10/2011.

The contrast with DEHP shows what a group restriction is worth: DEHP is FCM 283 and carries an individual specific migration limit of 0.6 mg/kg following Regulation (EU) 2023/1442, one hundredth of the group-32 ceiling. All 22 group-32 substances are listed on plasticizers in food contact materials.

Is ATBC FDA approved for food contact?#

ATBC is a prior-sanctioned plasticizer under 21 CFR 181.27, and under the FDA name tributyl acetylcitrate it is also listed in 21 CFR 172.515 for synthetic flavouring substances, 175.105 for adhesives, 175.300 for resinous and polymeric coatings, 175.320 for coatings on polyolefin films and 178.3910 for surface lubricants, which is a different legal route from an approval. A prior sanction is a clearance issued by the FDA or the USDA before the 1958 Food Additives Amendment and carried forward in part 181, so the substance is lawful for the sanctioned use without a food additive regulation or a food contact notification.

The distinction changes what a declaration of compliance can say. Prior sanctions, food additive regulations and food contact notifications are separated on FDA food contact rules (21 CFR), and no percentage limit or food-type condition for ATBC is recorded here.

Is ATBC allowed in toys and childcare articles?#

ATBC is not restricted in toys under EU REACH Annex XVII, US 16 CFR 1307 or Canada's SOR/2016-188, because none of those rules lists a citrate ester. Entry 52 names DINP, DIDP and DNOP in mouthable toys and childcare articles, 16 CFR 1307 names DEHP, DBP and BBP permanently plus DINP, DIBP, DPENP, DHEXP and DCHP from 25 April 2018, and SOR/2016-188 names six phthalates. The complete toy additive package is on additives in toys and childcare articles.

The forward-looking rule is written by hazard class rather than by substance name. Regulation (EU) 2025/2509, the Toy Safety Regulation, entered into force on 1 January 2026 and applies generally from 1 August 2030, banning CMR substances and endocrine disruptors in toys; ATBC carries no harmonised CMR classification under CLP Annex VI. The 8 restricted phthalates of the US rule are listed on CPSIA phthalate limits.

Is ATBC listed under California Proposition 65?#

ATBC is not on the Proposition 65 list: it does not appear on the OEHHA list edition of 31 July 2026, checked on 25 September 2026. DEHP, by contrast, has been listed since 1 January 1988 for cancer and since 24 October 2003 for developmental and male reproductive toxicity, and DINP has been listed for cancer since 20 December 2013, so the contrast between ATBC and the ortho-phthalates it replaces is a real one. Listing dates for plasticizers are maintained on California Proposition 65.

Is ATBC Safe? Health, Safety and Environmental Profile#

ATBC has no harmonised hazard classification under the EU CLP Regulation (EC) No 1272/2008, and 2,150 of the 2,180 companies that notified it to ECHA report that it does not meet the GHS hazard criteria. That is a classification statement, not a verdict, and the 3 elements of the regulatory hazard picture for acetyl tributyl citrate are listed below.

• Harmonised classification: none. ATBC does not appear in Annex VI of the CLP Regulation, so no EU-wide classification, labelling or packaging requirement is attached to it.
• Self-classification: the ECHA classification and labelling inventory records ATBC as not classified, with 2,150 of 2,180 notifying companies reporting that it does not meet the GHS hazard criteria.
• Regulatory concern lists: ATBC is not a Substance of Very High Concern, does not appear on Annex XIV or Annex XVII of REACH, and is not listed under the EU POPs Regulation (EU) 2019/1021.

What has not been assessed matters as much as what has. No LD50, no NOAEL, no endocrine assessment and no biodegradation test result for ATBC is recorded here, and the one documented environmental behaviour is hydrolysis after migration, reported by Höglund, Hakkarainen and Albertsson in Biomacromolecules in 2010, which is a degradation observation in water and not a biodegradation classification. Consumer concerns summarised on phthalates: health effects relate to ortho-phthalates and their metabolites, so they do not transfer automatically to a citrate ester, and the absence of a phthalate classification is not by itself evidence of a favourable toxicological profile.

What Are the Alternatives to ATBC?#

The 3 alternatives recorded for ATBC are TBC, DINCH and DOTP (DEHT), and the substance it most often replaces is DEHP, the ortho-phthalate restricted under REACH Annex XVII entry 51. The 6 plasticizers below are separated by chemical class, molecular weight and the regulatory routes that decide where each one can be used.

Table T6. ATBC compared with 5 other plasticizers.

Footnote: an FDA cell reads "not stated" where no verified 21 CFR route for that substance is held in our source library, which is not a statement that no clearance exists; it reads "none" only where the FDA inventories were searched and returned nothing, as for DINCH on 25 September 2026.

Full property data for the commodity esters sit on the plasticizer comparison page.

ATBC vs DOTP (DEHT)#

DOTP is the volume plasticizer and ATBC is the sensitive-application plasticizer: DOTP holds its own specific migration limit of 60 mg/kg as FCM 798, while ATBC has no individual limit and is capped only through group restriction 32. The difference appears when a compound carries two or more plasticizers: an individual limit is consumed by one substance, while a group limit is shared across every listed member.

Both belong to the same post-phthalate generation: the Wiesinger 2024 survey found ATBC and DEHT together in the replacement set for PVC toys, and neither is an SVHC. DOTP / DEHT (dioctyl terephthalate) holds its own SML of 60 mg/kg as FCM 798, and no substitution factor or price comparison is recorded here.

ATBC vs DINCH#

ATBC and DINCH share the same EU food-contact route, no individual SML plus group restriction 32, but they diverge in medical devices: the European Pharmacopoeia names DINCH as a DEHP alternative for PVC blood containers and does not name ATBC. DINCH carries CAS 166412-78-8, the US product number 474919-59-0 and a molecular weight of 424.7 g/mol, the highest in Table T6, and it is a cyclohexane-1,2-dicarboxylate rather than an aromatic ester.

DINCH (Hexamoll DINCH) is one of the four Ph. Eur. alternatives for blood containers, with BTHC, TOTM and DEHT. In toys the two are interchangeable on the regulatory side, since both appear in the Wiesinger 2024 replacement set and neither is listed in Annex XVII entries 51 or 52.

ATBC vs TBC and TEC#

Within the citrate family, molecular weight sets the roles: TEC at 276.28 g/mol goes into cellulosics and pharmaceutical coatings, TBC at 360.4 g/mol into PVC and nitrocellulose, and ATBC at 402.5 g/mol into PVC, PLA and food film. TEC carries CAS 77-93-0 and the formula C12H20O7, is authorised as food additive E1505, and plasticises cellulose acetate, cellulose nitrate, PVAc and pharmaceutical coatings.

Only two of the three are on the EU Union list. ATBC is FCM 138 and triethyl citrate (TEC) is FCM 140, both with no individual SML and both under group restriction 32, while TBC is not listed in Annex I in the consolidated text of 14 July 2026. TEC carries the same 21 CFR 181.27 prior sanction as ATBC, and the ECHA notifications for TBC report H318 where those for ATBC and TEC report no classification.

ATBC vs DEHP (DOP)#

ATBC replaces DEHP in exactly the uses where DEHP is now hardest to defend: DEHP is an SVHC, requires authorisation, is capped at 0.1 % in all articles under Annex XVII entry 51 and carries a harmonised Repr. 1B classification, while ATBC carries none of those. DEHP, CAS 117-81-7, entered the Candidate List on 28 October 2008, moved to Annex XIV as entry 4 with a sunset date of 21 February 2015, and carries hazard statement H360FD under CLP Annex VI.

The food-contact and medical files run the same way. DEHP (DOP, dioctyl phthalate) needs REACH authorisation; ATBC does not, and where DEHP is held to 0.6 mg/kg as FCM 283, ATBC sits inside the 60 mg/kg group ceiling. For medical devices, Regulation (EU) 2023/2482 sets a latest application date of 1 January 2029 and a sunset date of 1 July 2030 for DEHP, the deadline driving the search for alternatives.

Who Manufactures ATBC? Grades and Suppliers#

ATBC is sold under 3 trade names recorded in this directory: Citroflex A-4 (Vertellus), Uniplex 84 (Lanxess) and Estaflex ATC, whose brand owner is not recorded here. The manufacturers field of the ATBC substance record is empty, so this page names brand owners only where a source attributes them, and names no capacity, location or certification. UNIPLEX is a Lanxess brand line, acquired when Lanxess completed the Chemtura acquisition on 21 April 2017, and the plasticizer our sources attribute Citroflex to Vertellus.

Table T7. ATBC trade names and brand owners.

More producers, their regions and their product lines are listed in our directory of plasticizer manufacturers, which carries the company records that Table T7 leaves open.

No ATBC price level and no customs tariff code are recorded in our source library, so this page publishes neither, although both are live related searches. Price drivers for citrate esters are tracked on plasticizer prices. Buyers should request the supplier's technical data sheet and safety data sheet, a food-contact declaration of compliance against Regulation (EU) No 10/2011 and, where the grade is sold as bio-based, an ASTM D6866 certificate that states a measured bio-based carbon content.

How Do Citrate Esters Fit into the Wider Plasticizer Family?#

ATBC is the highest-volume member of the citrate class of plasticizers, the citric-acid esters that sit beside ortho-phthalates, terephthalates, trimellitates, cyclohexanoates and adipates in a plasticizer market of 8.4 million tonnes a year according to European Plasticisers. Citrates are defined by their parent acid: every member is an ester of citric acid, acetylated or not, and the class serves toys, medical devices, PLA, food contact and pharmaceutical coatings. No tonnage or market share for the class is recorded here. The class is covered on citrate plasticizers.

The 5 citrate plasticizers: ATBC, TBC, TEC, ATEC and BTHC#

Our source library records 5 citrate plasticizers: ATBC, tributyl citrate (TBC), triethyl citrate (TEC), acetyl triethyl citrate (ATEC) and butyryl trihexyl citrate (BTHC). Their roles are listed below.

• ATBC, 402.5 g/mol, the PVC, PLA and food-film member, FCM 138 under group restriction 32.
• TBC, 360.4 g/mol, the un-acetylated parent for PVC and nitrocellulose, not listed in Annex I of Regulation (EU) No 10/2011.
• TEC, 276.28 g/mol, the cellulosics and pharmaceutical-coating member, FCM 140 and food additive E1505.
• ATEC, acetyl triethyl citrate, named among the prior-sanctioned plasticizers of 21 CFR 181.27; no substance record exists here.
• BTHC, 514.7 g/mol, CAS 82469-79-2, the blood-bag citrate of the PL 2209 platelet-storage container.

BTHC (butyryl trihexyl citrate) is one of the four DEHP alternatives the European Pharmacopoeia names for PVC blood containers.

ATBC and the "phthalate-free" claim#

A "phthalate-free" label on a PVC article says which plasticizer the compounder added, not which plasticizer the article contains, because recycled PVC carries legacy phthalates into new parts. The Wiesinger 2024 survey makes the point with numbers: ATBC was one of 5 substances replacing restricted phthalates in PVC toys, and the same analysis still detected restricted phthalates in samples on sale, attributed mainly to recycled content. What the label does and does not guarantee is set out on phthalate-free plastics.

What are the three types of plasticizers?#

Plasticizer suppliers such as Hallstar group specialty plasticizers into 3 types: low-temperature, high-temperature and permanent (polymeric), with the general-purpose commodity esters, including phthalates and terephthalates, forming a fourth group beside them. The 3 specialty groups are listed below.

• Low-temperature plasticizers, such as aliphatic diesters, glycol esters and oleates, which hold flexibility below freezing.
• High-temperature plasticizers, such as trimellitates and pentaerythritol esters, which resist volatilisation.
• Permanent plasticizers, the polymerics, which resist extraction.

A second division cuts across the first: a primary plasticizer such as ATBC softens the resin alone, while a secondary plasticizer has to be blended with one. All classes are compared on the hub for types of plasticizers.

ATBC outside plastics: cosmetics, pharmaceutical coatings and flavouring#

ATBC is also used outside plastics, in nail polish, pharmaceutical film coatings and as a flavour-industry substance with FEMA number 3080, and those uses are outside the scope of this reference. Search results for the chemical name are dominated by cosmetic and pharmaceutical databases rather than plastics sources, which is why this page carries the plastics view.

What does ATBC stand for?#

In plastics, ATBC stands for acetyl tributyl citrate, CAS 77-90-7. The same abbreviation is used by the Association for Tropical Biology and Conservation, which is unrelated to plasticizers.

Is ATBC biodegradable?#

No biodegradation test result for ATBC is recorded in this directory, so the widespread "biodegradable" claim is not verifiable here; what is documented is hydrolysis: Höglund, Hakkarainen and Albertsson reported in Biomacromolecules in 2010 that ATBC migrates into water on immersion and then hydrolyses. Hydrolysis of an ester in water is a chemical reaction, not a biodegradation classification.

Does ATBC need an SDS?#

Yes: suppliers provide a safety data sheet for ATBC as for any traded chemical, even though ECHA classification and labelling notifications report it as not classified. A data sheet showing no hazard classification in section 2 still records identity, handling and storage.