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Food Grade Coatings

We Can Help You Meet FDA Regulations

Food grade coatings must comply with FDA regulations in 21 CFR 177.1550 governing
components of coatings for direct food contact. The FDA and other regulatory bodies dealing
with the food and pharmaceutical industries require that strict guidelines be followed in any
process affecting their manufacturing equipment.

While there are many coatings (such as wax coatings on meat wrapping paper) available that
comply with FDA regulations, the FDA conforming coatings that we apply are metallic and
fluoropolymer coatings.

Common Food Grade Coatings

Electroless Nickel (EN) is an autocatalytic coating, often recommended for use on steel parts.

A minimum thickness of .001" of Electroless Nickel will adequately protect the metal base from
corrosion. Electroless Nickel is, in actuality, not nickel, but a nickel-phosphorous overlay.

This coating will resist caustic, sulfate, chloride and other organic solutions but nitrates will
discolor the surface. Additionally, Electroless Nickel has good lubricity and a Rockwell hardness
ranging from 52-60.

It has several unique advantages; as an electroless process, it can be applied to inside diameters
and even blind holes. It is extremely uniform in thickness as can even be used to restore
undersized threads without the need for subsequent grinding. It can be heat treated to high
hardness, and is non-conducting, which is important where galvanic attack is a consideration.

EN/PTFE is a unique combination of EN co-deposited with a fluoropolymer (PTFE).

It can be applied at thicknesses up to .003" although it makes a better coating in most cases at
thickness of .0003"-.0005".

It uniquely combines the properties of EN with the properties of PTFE allowing for greater
lubricity, release and non-stick properties.

Fluoropolymer coatings can be applied as the final step or as the only finishing step in any
metal manufacturing process in order to increase a parts release properties.

After a fluoropolymer application, a part will feel slick to the touch and will exhibit a very low
coefficient of friction. Some parts used in high-stress environments such as bending or sliding
require a fluoropolymer coating.

Clear fluoropolymer coatings can be used so as not to change the color of the underlying part,
since they will merely reflect the color of the base material.
Hard coat Anodizing (HCA) is an electrochemical process is applied to aluminum alloys, which
transforms the surface to aluminum oxide. It transforms the soft aluminum into a wear and
corrosion resistant medium, attaining a Rockwell hardness of 48-54. Like EN, HCA also has
good lubricity.

Choosing a proper aluminum alloy prior to manufacturing will allow for determination of the
eventual thickness, corrosion resistance, and color of the alloy, since every alloy responds
differently to the coating process.

Harsh caustic or highly acidic solutions will eventually disintegrate a hard coat part, requiring
that highly trained and highly knowledgeable personnel understand that concentrated solutions
are not always superior in a maintenance wash down, but rather that mild detergents in warm
water will extend the longevity of the coating.

Passivation is not a coating; however, it is very useful in creating a very smooth, clean surface
on metal parts such as stainless steel, aluminum and titanium.

Passivation remove traces of iron embedded at the surface of metal parts during manufacturing
processes such as machining and milling. Passivating actually cleans the surface of all metallic
impurities, making it an essential part of the metal manufacturing cycle for food grade

Electropolishing is also not a coating. It makes all kinds of metal parts last longer and perform

Electropolishing uses a reverse plating technique where a metal or alloy is immersed in a

chemically balanced solution through which a low voltage current is passed. In this controlled
process, just the right amount of surface metal is removed.

Electropolishing does not smear, bend, stress or fracture the metal. It results in a smooth,
lustrous, more corrosion resistant finish that is passive and less prone to metal fatigue. It is
generally less expensive than mechanical polishing and produces far superior results, leaving the
surface microscopically featureless.

Contact ICS TECHNOLOGIES for help selecting the right food grade coating for your situation.
Corrosion Resistance
Combat the Effects of Corrosion

An estimated $300 billion is lost to corrosion every year. Corrosion resistant coatings are
important tools to combat the effects of corrosion in many manufacturing and maintenance

There are two basic types of corrosion that our coatings combat - Oxidation and Chemical

About Oxidation

Steel corrodes in reaction with its environment because of the unstable condition of iron after it
has been removed from its ores. Eventually, balance must be restored by return of the unstable
metal to its oxidized state. In the case of steel this usually appears as oxidation, otherwise known
as rust.

How Coatings Resist Oxidation

There are two different mechanisms by which coatings resist oxidation:

Barrier Coatings provide a barrier through which it is difficult for oxygen to permeate the
coating to the substrate. Since oxidation can only take place when oxygen is present, eliminating
or reducing the amount of oxygen stops or greatly reduces the rate of oxidation.

Examples of barrier coatings whose primary characteristic is corrosion resistance are high build
epoxies and polymer coatings such as nylon and fluoropolymers (e.g. Teflon ®).

Sacrificial Coatings sacrifice themselves in order to protect the substrate. They do this because
they are lower on the noble scale than the substrate (i.e. gold corrodes very slowly, stainless steel
corrodes faster than gold, mild carbon steel corrodes faster than stainless steel, zinc corrodes
faster than mild carbon steel, aluminum corrodes faster than zinc and magnesium corrodes faster
than aluminum).

Examples of sacrificial coatings whose primary characteristic is corrosion resistance are thermal
spray aluminum (TSA), thermal spray zinc (TSZ) and inorganic zinc.

About Chemical Corrosion

Chemical corrosion occurs when a corrosive product such as hydrochloric acid comes into
contact with an incompatible material such as stainless steel. The corrosive product acts on the
substrate to attack and wear away the metal resulting in costly damage.
A barrier coating is the only way to stop chemical corrosion, effectively sealing the metal
surfaces from contacting the corrosive liquid or solid.

Barrier Coatings create a barrier between the corrosive environment and your equipment. The
most important role of a coating is the isolation from the environment, but if complete isolation
can not be achieved due to pores, scratching or other discontinuities some coatings can still
suppress the rate of corrosion.

When your primary consideration is chemical corrosion resistance, consider using our services to
apply a coating that will meet your needs. ICS TECHNOLOGIES understands the process of
chemical corrosion. This understanding provides us with the key to steps that must be taken to
prevent chemical corrosion from occurring and identify the coating that best meets your needs.

Let ICS TECHNOLOGIES help prevent your company from becoming a corrosion statistic. For
a recommendation on any particular coating, please contact ICS TECHNOLOGIES.