Antifog Additives: 5 Types, Mechanisms, Dosage and Selection

Antifog additives are non-ionic surfactants that migrate to the surface of a plastic film and raise its surface energy, so condensed water spreads into a clear continuous layer instead of light-scattering droplets, and the 5 chemistry classes used in film sit at roughly 0.2 to 2.0 % of the film. A fogged lidding film hides the product on the shelf and a fogged greenhouse film cuts the light the crop gets, so which surfactant clears it, and for how long?

Antifog additives are one of the 6 surface and optical modifiers among the 43 families of plastic additives, and in film they are almost always dosed as a concentrate rather than as a neat ester. Antifog is one of the standard additive-masterbatch types listed for biaxially oriented polypropylene film, beside antiblock, antistat, migrating and non-migrating slip and white, and it appears again in the biaxially oriented polyethylene line.

This page defines fogging, separates hot fog from cold fog, sets the internal additive against the external coating, explains the blooming mechanism and why it fades, sets out the 5 chemistry classes in migration order, matches each to a film and a polymer, gives the dosage window in wt% and the masterbatch arithmetic, shows how antifog competes with slip, antiblock, antistat and the sealing surface, lists the 4 test measurements, states the EU and US food-contact positions, names the suppliers, and closes with the 5 antifog substance pages on this site.

Table T1. The 5 antifog classes at a glance.

Levels are supplier recommendations (Palsgaard Einar grades) or study formulations, not grade specifications. The US limits in class 5 are the maximum use levels written into 21 CFR 178.3130. EU entries are from the Union list as consolidated on 16 March 2025.

What Is an Antifog Additive?#

An antifog additive is a non-ionic surfactant, usually a fatty-acid ester of glycerol, sorbitan or polyglycerol, that is compounded into a plastic film and migrates to its surface, where it raises the surface energy enough for condensed water to spread into a continuous transparent layer. The same product travels under several names: anti-fog additive, anti-fogging agent, antifogging additive and, in agricultural film, drip agent or dripping agent. The Hanser Plastics Additives Handbook in its 6th edition gives antifogging additives a chapter of their own, beside antistatic additives and slip additives.

Two things an antifog additive is not are worth stating at the start. It is not a coating applied to a finished lens, mirror or visor, which is a consumer product handled once below this page's contextual border, and it is not an antistatic agent, although several of the same esters do both jobs and glycerol monostearate is filed on this site under antistatic agents for that reason. Why does water bead on a polyolefin film at all?

What is fogging in plastic film?#

Fogging is the loss of film transparency caused by condensed water standing as separate droplets on the film surface, which happens because water has a surface energy of 0.072 J/m2 while a polyolefin surface is far lower, so the water beads instead of wetting. Each droplet acts as a small lens, and a surface covered in them scatters the light that should pass through, which is what the eye reads as fog. The Avient packaging anti-fog whitepaper uses this surface-energy figure as the basis of its contact-angle argument.

Fogging shows up in 4 places in the film trade:

• Lidding films on chilled trays of meat, fish and prepared food, where fog hides the product at the point of sale.
• Bags and pouches of fresh produce, meat and fish, where respiration and drip water load the headspace.
• Shrink and stretch film over hot or humid contents, where vapour condenses as the pack cools.
• Greenhouse and tunnel film, where the drops cut light transmission and fall on the crop.

The word carries a second, unrelated meaning in plastics: in automotive interiors, fogging is the condensate that volatile additives leave on the inside of a windscreen, measured under DIN 75201. Both senses are separated on the glossary entry for fogging.

What is the difference between hot fog and cold fog?#

Cold fog is condensation that forms on chilled packaging in a refrigerated cabinet, while hot fog forms when hot-filled or microwaved contents drive water vapour onto a warm film, and the two need different grades and different levels. Cold fog is the chilled-display case: fresh produce, meat, fish and dairy behind a lidding or cling film. Hot fog is the hot-filled or microwaved ready meal and the heated counter, where the film is warm and the vapour load is high.

The level moves with the fog type across the polymer range. Palsgaard recommends its glycerol monostearate grade Einar 211 at 0.3-0.6 % in LDPE and LLDPE film for cold fog but only 0.2-0.4 % for hot fog, and at 0.5-1.0 % against 0.3-0.6 % in PVC cling film. In polypropylene the same pattern holds across two grades: the polyglycerol ester Einar 618 sits at 1.0-1.5 % in random copolymer film for cold fog, while Einar 422, a hot-fog grade whose chemistry Palsgaard does not disclose, sits at 0.5-1.0 % in the same polymer.

Suppliers segment their grade ranges this way, but the split is commercial segmentation rather than a standardised classification, so a hot-fog grade from one producer is not a defined equivalent of a hot-fog grade from another.

Internal antifog additive or external antifog coating?#

There are 2 ways to give a polyolefin film antifog performance: compound an internal antifog additive into the resin, usually as a masterbatch, so that it migrates to the surface during and after extrusion, or spray an external antifog coating onto the finished film. Avient names exactly these two routes in the same whitepaper, and the choice between them decides almost everything else about the product.

The two routes differ on 4 points. The internal route is applied at the extruder as part of the melt, the external route after extrusion to a finished web. The internal route lasts as long as the reservoir of ester inside the film lasts, a surface coating as long as it stays on the surface. The internal route fails when the reservoir is exhausted, a coating when it is washed or wiped off. Everything that follows concerns the internal route, because a sprayed coating is a coating rather than a plastics additive and sits at the edge of this site's border.

How Do Antifog Additives Work?#

Antifog additives work by blooming: the ester is only partly compatible with the polymer, so it diffuses to the polymer and air interface, where its hydrophilic head raises the surface energy of the film and water that condenses on it spreads instead of beading. The molecule is amphiphilic, with a fatty hydrophobic tail anchored in the polyolefin and a polyol head that points outward. Nouman and colleagues describe the general case in Polymer Degradation and Stability (2017): an additive blooms when it sits above its solubility in the polymer at the use temperature, and the rate at which it arrives is set by its diffusion coefficient.

The measured consequence is a lower contact angle. Zha and colleagues at Hebei University of Technology measured a water contact angle of 38° on an LLDPE greenhouse film containing glycerol monostearate (ACS Omega, 2024), which is the wetting regime in which droplets coalesce rather than stand apart.

The mechanism runs in 4 steps:

1. Compound the ester above its solubility in the polymer, so that it is supersaturated after cooling.
2. Let it diffuse to the polymer and air interface, where the hydrophilic head orients outward.
3. Raise the surface energy of the film, which lowers the contact angle of water on it.
4. Let the droplets merge into a continuous transparent layer that runs off instead of scattering light.

Why does antifog performance fade? Migration, wash-off and the surfactant reservoir#

Antifog performance fades because the working layer is a surface layer: condensate washes the ester off, more ester migrates out of the bulk to replace it, and the effect stops when the reservoir in the film is exhausted. That replenishment cycle is recorded in the mechanism description for glycerol monostearate itself, and the general case of an additive physically leaving the polymer is covered under additive volatility, extraction and fogging. The consequence is that antifog is a consumable, not a permanent surface treatment.

Three mechanisms take the surfactant out of service:

• Wash-off, where the condensate that the additive has spread carries dissolved ester away with it each time the film sheds water.
• Depletion, where the bulk of the film no longer holds enough ester above its solubility limit to drive further diffusion to the surface.
• Crystallisation, recorded for glycerol monostearate, whose surface layers can crystallise and lose effect, and which gives only about 1 to 2 months of antistatic performance from the same surface mechanism.

Time-scales differ by an order of magnitude between applications: work on PE and EMAA blend films published in Polymers (2019) reports that the surfactants in greenhouse film usually disappear within two years, which is the outer bound for a drip agent.

Formulators have three levers against a bloom that runs too fast: a higher molecular weight or oligomeric grade, a closer solubility-parameter match to the polymer, or a lower loading. Other bloom and migration faults are indexed on troubleshooting additive-related defects.

5 Types of Antifog Additives#

The 5 types of antifog additives used in plastic film are glycerol esters such as GMS and GMO, sorbitan esters such as Span 60 and Span 80, polysorbates, polyglycerol esters, and a small group of other surfactants that includes the glycerol ricinoleate esters used in plasticized PVC. They are listed here from the fastest-migrating to the slowest, because migration speed decides whether a film clears in minutes or stays clear for a season, and the polyglycerol esters at the end of the list are the class our source library records as performing where long antifog life is needed.

1. Glycerol esters: GMS and GMO#

Glycerol esters are monoesters of glycerol with a single C18 fatty acid, and the two used as antifogs differ by one double bond: glycerol monostearate is saturated and solid, glycerol monooleate is unsaturated and liquid. Both carry an entry on the EU Union list and a US listing as a direct food substance, and both are the best documented antifog chemistries in our source library, which is why they lead the list.

Glycerol monostearate (GMS)#

Glycerol monostearate, CAS 31566-31-1, is a waxy saturated monoglyceride dosed at 0.3-0.6 % for cold fog and 0.2-0.4 % for hot fog in LDPE and LLDPE film, and at 0.5-1.0 % and 0.3-0.6 % in PVC cling film. It also carries CAS 123-94-4 and, as the commercial mixture "Glycerides, C16-18 mono-", CAS 91052-47-0, with EC number 250-705-4. The molecule is C21H42O4 at 358.6 g/mol, a white to pale yellow waxy solid of density 0.97 g/cm3 at 25 °C; the melting point belongs to the grade, at 56-62 °C for Baerolub L-MS, a roughly 40 % monoester grade, and 58-60 °C for Struktol TR 151-40. It sells as Atmer 129, Armostat 801, Einar 211, Struktol TR 151-40 and TR 151-95, Baerolub L-MS and Ligalub 11 GE.

GMS is the main ingredient of many commercial dripping agents for LLDPE greenhouse film, and it is the substance on which the 38° contact angle was measured. It holds EU FCM No 53 (Ref 56585, glycerol esters with stearic acid) with no specific migration limit, 25 active REACH dossiers under EC 250-705-4 plus 22 under CAS 91052-47-0 in ECHA CHEM as checked on 22 September 2026, no place on the Candidate List at that date, and a TSCA listing. In the US it is GRAS as a direct food substance under 21 CFR 184.1324; the food-packaging route for a given grade runs through 21 CFR 178.3130 or 178.3400 and has to be confirmed per grade. GMS also works as an internal lubricant for clear PVC, which is covered under internal lubricants for PVC.

Glycerol monooleate (GMO)#

Glycerol monooleate, CAS 25496-72-4, is the unsaturated counterpart of GMS, a liquid monoglyceride named by Palsgaard as a conventional antifog chemistry for polyethylene film. It is also indexed under CAS 111-03-5, with EC numbers 247-038-6 and 203-827-7, and the molecule is C21H40O4 at 356.5 g/mol. Trade usage calls it monoolein, glyceryl monooleate or simply glycerol oleate.

No film dosage for GMO appears in our sources, and the GMS range is not transferable to it, so the level has to come from the supplier of the grade in hand. Its food-contact position is documented: EU FCM No 49 (Ref 56540, glycerol esters with oleic acid) with no specific migration limit under the Union list as consolidated on 16 March 2025, and GRAS status as a direct food substance under 21 CFR 184.1323. An ECHA CHEM query returned no active REACH dossier under either EC number, which is a registration status rather than a safety finding.

2. Sorbitan esters (Span)#

Sorbitan esters are fatty-acid esters of the sorbitol anhydride sold under the Span and Arlacel names, and the two used as antifogs in polyethylene and polypropylene film are sorbitan monostearate (Span 60, CAS 1338-41-6) and sorbitan monooleate (Span 80, CAS 1338-43-8). Sorbitan monostearate is C24H46O6 at 430.6 g/mol, a white to tan solid melting at 49-65 °C with a density of 1.0 at 25 °C, under EC 215-664-9, with 32 active REACH dossiers, no Candidate List entry and no classification in 97.9 % of GHS notifications. Sorbitan monooleate is C24H44O6 at 428.6 g/mol, a yellow to amber viscous liquid under EC 215-665-4 with no active dossier found. Further members of the family are used as emulsifiers, but only these two hold substance records in our source library.

Both are conventional antifog chemistries for PE and PP film, and Span 60 is named as an internal dripping agent for polyethylene by Zha and colleagues (ACS Omega, 2024). The one published formulation in our sources are agricultural rather than packaging. In a coextruded LDPE and EVA agricultural film, Waldo-Mendoza and co-workers found that 3 wt% of surfactant in the EVA layer plus 1 wt% in the LDPE layer worked and that 5 wt% did not improve wetting (Membranes, 2017); the best antifog permanency in that work ran close to 3,000 h, while sorbitan-type and polyglycerol-ester antifogs held an acceptable rating for about 1,000 to 1,500 h. Those are study figures for agricultural film, not a packaging recommendation. In food contact, sorbitan monostearate holds EU FCM No 415 (Ref 87840) with 21 CFR 172.842 and 178.3400, and sorbitan monooleate FCM No 416 (Ref 87680) with 21 CFR 178.3400 and 173.75, none of them with a specific migration limit.

3. Polysorbates: ethoxylated sorbitan esters#

Polysorbates are sorbitan esters with polyethylene glycol chains added, which makes them more hydrophilic than the Span grades they are built from, and they appear on most industry lists of antifog chemistries. The best known member is polysorbate 80, polyoxyethylene (20) sorbitan monooleate, CAS 9005-65-6, sold under the Tween name.

In our source library their plastics use is narrow: polysorbate 80 is recorded mainly as a food and cosmetic emulsifier, with occasional use as a drip agent in greenhouse film, and no film dosage is published in the sources we checked. That greenhouse drip-agent use is covered on antifog additives for greenhouse film. On the regulatory side, sorbitan esters and their ethoxylates are covered by Union list entries and by 21 CFR 178.3400 for emulsifiers and surface-active agents, but the only Union list numbers verified in our substance records are FCM 415 and FCM 416 for the two Span grades, so no polysorbate entry is stated here as fact.

4. Polyglycerol esters (PGE)#

Polyglycerol esters are fatty-acid esters of oligomeric glycerol, and they are the slow, long-life antifog class: Palsgaard's Einar 618 is dosed at 1.0-1.5 % in random-copolymer polypropylene film and at 1.5-2.0 % in homopolymer film. The class member with an identity record is triglycerol monostearate, CAS 26855-43-6, ECHA list number 978-493-5, C27H54O8 at 506.7 g/mol. Palsgaard also sells Einar 614 as a general-purpose polyglycerol-ester antifog for PE film, with no level published in our sources, and Einar 422 as a hot-fog PP grade at 0.5-1.0 % in random copolymer and 1.0-1.5 % in homopolymer, whose chemistry the company does not disclose and which is therefore not a polyglycerol ester for the purposes of this page.

Polyglycerols perform where long antifog life is needed, which is what puts them into greenhouse film rather than into a lidding film that has to clear once. The same polyglycerol esters are sold as pigment dispersing aids at 1-5 % of a colour masterbatch formulation for PE, PP, PET, PVC and PA, which is covered under dispersing agents for masterbatch. For food contact, the class holds EU FCM No 11 (Ref 30960, esters of C6-C22 monocarboxylic acids with polyglycerol) and polyglycerol itself FCM No 1017 with a processing limit of 275 °C, neither with a specific migration limit, while the US route is 21 CFR 172.854. Palsgaard is the manufacturer named in our records for the Einar line.

5. Other antifog chemistries: ethoxylates, polysiloxanes and the PVC entries#

Beyond the three ester families, the antifog chemistries named in the general literature are ethoxylates and polysiloxanes, and the US food-contact rules name three more specific antifog substances with their own maximum levels. Those two class names come from general secondary sources rather than a primary technical record, so they are named here as reported chemistries without CAS numbers, levels or suppliers. The three US entries are different: each is written into 21 CFR 178.3130, the section covering antistatic and antifogging agents in food-packaging materials, with its own limit and film restriction.

• Glycerol ricinoleate ester mixtures, up to 1.5 wt% as an antifog in plasticized polyvinyl chloride.
• N-acyl sarcosines, up to 0.15 wt% in polyolefin film not thicker than 0.003 in for packaging meat and fresh produce, and in ethylene-vinyl acetate film.
• Alpha-(carboxymethyl)-omega-(tetradecyloxy)polyoxyethylene, up to 0.2 wt% in polyolefin film not thicker than 0.001 in.

The film-thickness restrictions are part of each limit, because the same weight percentage in a thicker film puts more substance against the food.

Which Antifog Additive Suits Each Film, Polymer and Fog Type?#

The right antifog depends on the polymer and on the fog: polyethylene film needs 0.2-0.6 %, polypropylene film needs 0.5-2.0 % because its higher crystallinity slows migration, and a hot-fog grade is always dosed below the cold-fog grade of the same chemistry. The crystallinity explanation is Palsgaard's, recorded with the loading comparison itself, and it also explains the second gradient inside polypropylene: homopolymer film needs more than random copolymer film, because the more crystalline matrix holds the ester back. Table T2 matches each film and polymer to the classes that our sources document for it.

Table T2. Film and polymer against antifog class.

Two rows are thinner than the others on purpose. No level is recorded for the BOPE line beyond the fact that antifog is one of its masterbatch types, and no antifog data exist in our sources for PET, polystyrene or PLA film, so those polymers carry no row rather than a borrowed number. The full slip, antiblock, antifog and antistat stack is on additives for packaging film.

How to select an antifog additive in 6 steps#

Select an antifog additive in 6 steps: name the fog, match the ester class to the polymer, set the required life, check the film structure, screen the food-contact route in each market, and confirm the level by trial. The sequence matters, because steps 1 and 2 set the class while steps 5 and 6 only narrow the grade.

1. Name the fog first: cold fog in chilled display, hot fog from hot filling or a microwave, or drip performance in a greenhouse. Those are the three segments suppliers build grades for.
2. Match the class to the polymer: glycerol or sorbitan esters for PE and PVC, polyglycerol esters for PP, at the levels in Table T3.
3. Set the required life: minutes to hours for a lidding film that has to clear on the shelf, a full season for a greenhouse film.
4. Check the film structure: which layer carries the ester and how much film mass stands behind it, because the reservoir that replenishes the surface is the ester held in the film.
5. Screen the food-contact status in each market, taking the EU Union list entry and the 21 CFR route separately.
6. Trial across the dosage window and measure fog with the supplier's hot-fog and cold-fog box test, because no published standard method exists.

Steps 5 and 6 should be run with the supplier rather than in isolation, since both depend on grade-specific information. The general method behind this sequence is on how to select plastic additives.

How Much Antifog Additive Is Needed? Dosage in wt%#

Antifog levels run from 0.2 % of the film for a hot-fog grade in polyethylene to 2.0 % for a cold-fog polyglycerol ester in homopolymer polypropylene, with PVC cling film in between at 0.3-1.0 %. Every figure below carries the polymer, the fog type and the basis it comes from, because a supplier grade recommendation, a published study formulation and a US regulatory maximum are three different kinds of number.

Table T3. Antifog level by class, polymer and fog type.

Units follow the polymer. Polyolefin film levels are quoted as wt% of the film, where 1 wt% equals 10,000 ppm, while PVC formulations are normally quoted in phr and have to be converted before the two can be compared; the unit rules are on conversion to wt%, ppm and let-down ratio. The class 5 figures are regulatory maxima, not recommended levels. The hot-fog level sits below the cold-fog level of the same chemistry in every grade pair recorded here, which is the most useful pattern in the table.

How is antifog masterbatch let down?#

Antifog is almost always bought as an additive masterbatch and let down at the extruder, so the dose follows from one division: the target level in the film divided by the active content of the concentrate. Antifog is one of the standard concentrate types for both BOPP and BOPE film, so it is sold as additive masterbatch rather than as a neat ester in most converting operations.

Example, arithmetic only: to reach 0.5 % antifog in the film from a concentrate containing 20 % active, add 2.5 % masterbatch, because 0.5 divided by 20 gives 0.025. The 20 % figure is illustrative and not a product value; the active content of a real concentrate comes from its technical data sheet.

One masterbatch maker, Mascom, publishes a let-down range of 1 to 3 %, which is consistent with a concentrate of roughly 10 to 30 % active at the film levels in Table T3; treat it as a single supplier's figure rather than an industry rule. Any concentrate can be checked against a target film level with the let-down ratio calculator.

How Do Antifog Additives Interact with Slip, Antiblock, Antistatic and Sealing?#

Antifog additives interact with the rest of a film formulation in 4 ways: they share the film surface with slip agents, they can be adsorbed by mineral antiblocks, several of them are antistats in their own right, and they bloom onto the same surfaces that have to weld. A polyethylene film package already contains slip at 0.05-0.12 %, an antiblock, a polymer processing aid and often an antistat, so the antifog ester is one of several species competing for the same surface and the same diffusion path.

Table T4. Antifog interaction partners.

The antiblock row is an inference stated as such. Mineral antiblocks are documented to adsorb migrating slip agents and antistats and to slow their arrival at the surface, so the same competition is to be expected with an antifog ester, but no measurement of that pair appears in our sources.

The antistatic overlap is the strongest of the four and is worth a formulation decision. Glycerol monostearate is filed primarily as an antistatic agent, delivers about 1 to 2 months of antistatic performance, and is combined with ethoxylated amines as a fast-plus-long-term pair; together those two chemistries account for more than half of the antistatic market. A film that already carries GMS for fog therefore starts with part of its antistatic requirement met. A full matrix of which additive helps and which hinders is on additive interactions.

How Is Antifog Performance Tested?#

Antifog performance is tested with 4 measurements: a hot-fog or cold-fog box test, an accelerated drip-duration test at 60 °C, the water contact angle on the film surface, and haze under ASTM D1003. The first is qualitative and supplier-specific, the second is written into a national film standard, and the last two are instrumented measurements that quantify the cause and the effect.

Table T5. What is measured and how.

One gap is worth stating plainly, because it changes how trial data should be read. No international standard method for hot-fog or cold-fog rating was found in our sources: every supplier runs its own box test with its own water temperature, geometry and rating scale, so a rating of 1 on one scale is not a rating of 1 on another and two suppliers' results are not directly comparable. A claim of better antifog performance means little unless both films were run in the same box on the same day. All methods used across additive families are indexed under testing plastic additives.

How Are Antifog Additives Regulated for Food-Contact Film?#

The antifog esters are authorised for food-contact plastics in both markets: each of the documented substances has an entry on the EU Union list without a substance-specific migration limit, and the US route runs through 21 CFR 178.3130 for antifogging agents or 21 CFR 178.3400 for surface-active agents. None of the antifog substances in our source library appears on the REACH Candidate List as checked on 22 September 2026, and every instrument named here is summarised in plastic additive regulations.

One distinction carries most of the compliance risk here. Several of these esters are cleared as food ingredients, which is a different authorisation from the clearance of the same substance in a packaging film. The full food-contact film stack is on additives for food packaging.

EU: Union list entries under Regulation (EU) No 10/2011#

Every antifog ester with a substance record in our source library appears on the Union list of Regulation (EU) No 10/2011 without a substance-specific migration limit, so the generic limit of 60 mg/kg and the overall migration limit of 10 mg/dm2 apply. Table T6 gives the entries as they stand in the Union list consolidated on 16 March 2025.

Table T6. Union list entries for the antifog esters.

The absence of a substance-specific SML does not remove a migration obligation, it changes which one applies, and compliance still has to be demonstrated for the finished article. These values are verified against the 16 March 2025 consolidation only; Regulation (EU) 2025/351 and Regulation (EU) 2025/2240 amend the instrument after that date and have to be checked against the current consolidated text before a declaration is written. How the Union list works is explained on EU 10/2011.

US: 21 CFR 178.3130, 21 CFR 178.3400 and the GRAS route#

In the US an antifog additive can reach food-contact use by three routes: 21 CFR 178.3130 for antistatic and antifogging agents, 21 CFR 178.3400 for emulsifiers and surface-active agents, or a direct-food-additive or GRAS listing that the packaging use is built on. The three are distinct sections with distinct scopes:

• 21 CFR 178.3130 lists antistatic and antifogging agents for food-packaging materials and carries the three substance-specific antifog limits given earlier, each tied to a maximum film thickness.
• 21 CFR 178.3400 covers emulsifiers and surface-active agents in food-contact articles and is the section cited in both sorbitan-ester records, with sorbitan monooleate specified by a saponification number of 145-160 and a hydroxyl number of 193-210.
• The direct-additive and GRAS listings sit outside the packaging subchapter: glycerol monostearate under 21 CFR 184.1324, glycerol monooleate under 184.1323, sorbitan monostearate under 172.842, polyglycerol esters under 172.854 and sorbitan monooleate also under 173.75.

The third route is where the common error sits. Being GRAS as a food ingredient is not the same clearance as being authorised in a packaging film, and our source library marks the US packaging route for glycerol monostearate as unconfirmed at grade level, so which route applies depends on the grade and has to be confirmed with the supplier. Every 21 CFR section relevant to plastic additives is mapped on FDA food contact rules.

Who Makes Antifog Additives? Ester Producers and Masterbatch Suppliers#

Antifog additives come from 2 supplier groups: ester producers such as Palsgaard, Croda, Nouryon and Struktol, which make the glycerol, sorbitan and polyglycerol esters themselves, and masterbatch makers such as Avient, Ampacet and Tosaf, which sell them as film concentrates. Converters buy from the second group, compounders and masterbatch makers from the first; company profiles for both sit in the directory of plastic additive manufacturers and suppliers.

Table T7. Suppliers named in our records.

Concentrate makers are compared on masterbatch manufacturers, which matters because the choice of masterbatch maker usually decides the ester as well: most converters never specify the chemistry directly.

No reliable published figure exists for the size of the antifog segment, and none is invented here; segment data for the families that do have sourced figures are on plastic additives market.

Complete List of Antifog Additive Substances (5 Pages)#

The table lists the 5 antifog substances with their own pages on this site, with CAS number, chemistry class, film function, main polymers and food-contact entries in both markets. The order is the class order used throughout this page.

Table T7b. The 5 antifog substances with their own page.

Glycerol monostearate is filed on this site under antistatic agents rather than under antifog, because it does both jobs and the antistatic use is the larger one; every other substance with a plastics function is in the plastic additives database.

Antifog Beyond the Packaging Line: Recycling, Consumer Sprays and Food Emulsifiers#

Three other things travel under the name anti-fog: what happens to these additives when the film is recycled, the consumer sprays and wipes sold for goggles and windshields, and the fact that the main antifog ester is also a food emulsifier. Each of the three reaches this page through search, and each is answered once here rather than in the main content, where it would dilute the film topic. None of them changes the selection, dosage or compliance decisions above.

Do antifog additives affect film recycling?#

The Association of Plastic Recyclers lists antifog agents among the workhorse additives in its PE flexible film design guide and classifies them as "Design Preferred", so at packaging-film levels they are not treated as a recycling barrier. "Design Preferred" is the guide's own category name and means that no significant recycling issue is identified, not that the film as a whole is recyclable. The same guide asks that workhorse additives be minimised, which is the usual framing for substances that are accepted rather than encouraged.

That status is specific to polyethylene flexible film. It does not extend to polypropylene film, PVC cling film or agricultural film, none of which the same guide entry covers. How each additive family affects the recycling route is set out in design for recycling.

Is an antifog additive the same as the anti-fog spray for goggles and windshields?#

No: an antifog additive is compounded into the plastic itself and works from the inside out, while a consumer anti-fog spray, wipe or coating is applied to the surface of an existing lens, mirror or visor and is reapplied when it wears off. The overlap is real at the level of chemistry, because both rely on surfactants that let water wet a surface instead of beading on it, which is the same physics described in the mechanism section above.

The difference that matters is where the substance lives: an antifog masterbatch is bought by a film converter in tonnes and disappears into the film structure, while a consumer product is applied to a finished article by its owner. This site covers additives used in plastics, so consumer sprays, wipes, eyewear coatings and automotive products are outside its scope and are not compared, rated or linked here.

Is antifog GMS the same substance as the food emulsifier E471?#

Glycerol monostearate used as an antifog is the same chemistry as the monoglyceride used as a food emulsifier, and it is GRAS as a direct food substance under 21 CFR 184.1324, but the grade, the purity specification and the clearance route for a packaging film are not automatically the same. The commercial GMS grades sold into plastics are mixtures: Struktol TR 151-40 is specified at 40 to 45 % monoglyceride and Baerolub L-MS at about 40 % monoester, which is a different specification from a food-grade emulsifier.

The same pattern runs through the other classes: sorbitan monostearate is a direct food additive under 21 CFR 172.842 and polyglycerol esters under 172.854, and each listing describes an ingredient rather than a component of a film. The European food-additive E numbers are a separate designation that our sources do not map to these records, so this page states the chemistry and the 21 CFR sections rather than the code, and the US packaging route for a given GMS grade still has to be confirmed with its supplier.

Antifog additive FAQs#

Three questions come up repeatedly once the chemistry and the dosage are settled, and each of them has a short, definite answer.

Does antifog reduce film clarity or heat sealing?#

Antifog additives are used to improve clarity under condensation, not to reduce it. Haze on a dry film is measured under ASTM D1003-21 and is the number to watch if a clarity claim is made. Because the ester blooms to the film surface, seal performance is checked alongside the fog rating whenever the level is changed; no seal-strength figure for an antifog film appears in our sources.

How long does antifog last in greenhouse film?#

Long-life greenhouse grades are designed to pass the accelerated dripping test in GB/T 4455-2019, which asks for more than 8 days at 60 °C and corresponds to roughly 3 months in the field. Published work on PE and EMAA blend films in Polymers (2019) reports that the surfactants usually disappear within two years, which is the practical ceiling for a drip agent in a multi-season structure.

Is an antifog additive FDA approved?#

The FDA does not "approve" additives: an antifog agent reaches food-contact use through 21 CFR 178.3130 for antistatic and antifogging agents, 21 CFR 178.3400 for surface-active agents, or a direct-food-additive listing, and which one applies depends on the grade. A supplier claim that a product is "food-safe" names no section and is not a compliance statement. Ask for the section number and the film thickness it applies to.