[Code of Federal Regulations]
[Title 21, Volume 3]
[Revised as of January 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR175.390]

[Page 196]
 
                        TITLE 21--FOOD AND DRUGS
 
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN 
                          SERVICES (CONTINUED)
 
PART 175_INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS OF 
 
         Subpart C_Substances for Use as Components of Coatings
 
Sec.  175.390  Zinc-silicon dioxide matrix coatings.

    Zinc-silicon dioxide matrix coatings may be safely used as the food-
contact surface of articles intended for use in producing, 
manufacturing, packing, processing, preparing, treating, packaging, 
transporting, or holding food, subject to the provisions of this 
section;
    (a) The coating is applied to a metal surface, cured, and washed 
with water to remove soluble substances.
    (b) The coatings are formulated from optional substances which 
include:
    (1) Substances generally recognized as safe.
    (2) Substances for which safe conditions of use have been prescribed 
in Sec.  175.300.
    (3) Substances identified in paragraph (c) of this section, subject 
to the limitations prescribed.
    (c) The optional substances permitted are as follows:

------------------------------------------------------------------------
            List of substances                       Limitations
------------------------------------------------------------------------
Ethylene glycol...........................  As a solvent removed by
                                             water washing.
Iron oxide................................
Lithium hydroxide.........................  Removed by water washing.
Methyl orange.............................  As an acid-base indicator.
Potassium dichromate......................  Removed by water washing.
Silica gel................................
Sodium silicate...........................
Zinc, as particulate metal................
------------------------------------------------------------------------

    (d) The coating in the finished form in which it is to contact food, 
when extracted with the solvent or solvents characterizing the type of 
food, and under the conditions of its intended use as shown in table 1 
and 2 of Sec.  175.300(d) (using 20 percent alcohol as the solvent when 
the type of food contains approximately 20 percent alcohol) shall yield 
total extractives not to exceed those prescribed in Sec.  175.300(c)(3); 
lithium extractives not to exceed 0.025 milligram per square inch of 
surface; and chromium extractives not to exceed 0.05 microgram per 
square inch of surface.
    (e) The coatings are used as food-contact surfaces for bulk reusable 
containers intended for storing, handling, and transporting food.