[Code of Federal Regulations]
[Title 21, Volume 3]
[Revised as of April 1, 2006]
From the U.S. Government Printing Office via GPO Access
TITLE 21--FOOD AND DRUGS
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN
PART 177_INDIRECT FOOD ADDITIVES: POLYMERS--Table of Contents
Subpart C_Substances for Use Only as Components of Articles Intended for
Sec. 177.2490 Polyphenylene sulfide resins.
Polyphenylene sulfide resins (poly(1,4-phenylene sulfide) resins)
may be safely used as coatings or components of coatings of articles
intended for repeated use in contact with food, in accordance with the
following prescribed conditions.
(a) Polyphenylene sulfide resins consist of basic resins produced by
the reaction of equimolar parts of p-dichlorobenzene and sodium sulfide,
such that the finished resins meet the following specifications as
determined by methods titled ``Oxygen Flask Combustion-Gravimetric
Method for Determination of Sulfur in Organic Compounds,''
``Determination of the Inherent Viscosity of Polyphenylene Sulfide,''
and ``Analysis for Dichlorobenzene in Ryton Polyphenylene Sulfide,''
which are incorporated by reference. Copies are available from the
Center for Food Safety and Applied Nutrition (HFS-200), Food and Drug
Administration, 5100 Paint Branch Pkwy., College Park, MD 20740, or
available for inspection at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/
(1) Sulfur content: 28.2-29.1 percent by weight of finished resin.
(2) Minimum inherent viscosity: 0.13 deciliters per gram.
(3) Maximum residual p-dichlorobenzene: 0.8 ppm.
(b) Subject to any limitations prescribed in parts 170 through 189
of this chapter, the following optional substances may be added to the
polyphenylene sulfide basic resins in an amount not to exceed that
reasonably required to accomplish the intended physical or technical
(1) Substances generally recognized as safe in food.
(2) Substances used in accordance with prior sanction or approval.
(3) Substances the use of which is permitted in coatings under
regulations in parts 170 through 189 of this chapter.
(c) The finished coatings are thermally cured at temperatures of 700
[deg]F and above.
(d) Polyphenylene sulfide resin coatings may be used in contact with
food at temperatures not to exceed the boiling point of water; provided
that the finished cured coating, when extracted at reflux temperatures
for 8 hours separately with distilled water, 50 percent ethanol in
water, and 3 percent acetic acid, yields total extractives in each
extracting solvent not to exceed 0.02 milligram per square inch of
surface and when extracted at reflux temperature for 8 hours with
heptane yields total extractives not to exceed 0.1 milligram per square
inch of surface.
(e) Polyphenylene sulfide resin coatings containing perfluorocarbon
resins complying with Sec. 177.1550 may be used in contact with food at
temperatures up to and including normal baking and frying temperatures;
provided that the finished cured coating, when extracted at reflux
temperatures for 2 hours separately with distilled water, 50 percent
ethanol in water, 3 percent acetic acid and heptane, yields total
extractives in each extracting solvent not to exceed 0.2 milligram per
square inch of surface and when extracted at reflux temperature for 1
hour with diphenyl ether yields total extractives not to exceed 4.5
milligrams per square inch of surface.
[42 FR 14572, Mar. 15, 1977, as amended at 47 FR 11846, Mar. 19, 1982;
54 FR 24898, June 12, 1989]
Additives that reference this regulation: