Resin-bonded filters may be safely used in producing, manufacturing, processing, and preparing food, subject to the provisions of this section.

(a) Resin-bonded filters are prepared from natural or synthetic fibers to which have been added substances required in their preparation and finishing, and which are bonded with resins prepared by condensation or polymerization of resin-forming materials, together with adjuvant substances required in their preparation, application, and curing.

(b) The quantity of any substance employed in the production of the resin-bonded filter does not exceed the amount reasonably required to accomplish the intended physical or technical effect or any limitation further provided.

(c) Any substance employed in the production of resin-bonded filters that is the subject of a regulation in parts 174, 175, 176, 177, 178 and § 179.45 of this chapter conforms with any specification in such regulation.

(d) Substances employed in the production of resin-bonded filters include the following, subject to any limitations provided:

List of Substances and Limitations

(1) Fibers:

Cellulose pulp. Cotton. Nylon. (From nylon resins complying with the provisions of applicable regulations in subchapter B of this chapter. Polyethylene terephthalate complying in composition with the provisions of § 177.1630; for use in inline filtration only as provided for in paragraphs (e) and (f) of this section. Rayon (viscose).

(2) Substances employed in fiber finishing:

BHT. Butyl (or isobutyl) palmitate or stearate. 2,5-Di-tert-butyl hydroquinone for use only in lubricant formulations for rayon fiber finishing and at a usage level not to exceed 0.1 percent by weight of the lubricant formulations. Dimethylpolysiloxane. 4-Ethyl-4-hexadecyl morpholinium ethyl sulfate for use only as a lubricant in the manufacture of polyethylene terephthalate fibers specified in paragraph (d)(1) of this section at a level not to exceed 0.03 percent by weight of the finished fibers. Fatty acid (C10-C18) diethanolamide condensates. Fatty acids derived from animal or vegetable fats and oils, and salts of such acids, single or mixed, as follows: Aluminum. Ammonium. Calcium. Magnesium. Potassium. Sodium. Triethanolamine. Fatty acid (C10-C18) mono- and diesters of polyoxyethylene glycol (molecular weight 400-3,000). Methyl esters of fatty acids (C10-C18). Mineral oil. Polybutene, hydrogenated; complying with the identity prescribed under § 178.3740 (b) of this chapter. Polyoxyethylene (4 mols) ethylenediamine monolauramide for use only in lubricant formulations for rayon fiber finishing and at a usage level not to exceed 10 percent by weight of the lubricant formulations. Ricebran oil. Titanium dioxide.

(3) Resins:

Acrylic polymers produced by polymerizing ethyl acrylate alone or with one or more of the monomers: Acrylic acid, acrylonitrile, N-methylolacrylamide, and styrene. The finished copolymers shall contain at least 70 weight percent of polymer units derived from ethyl acrylate, no more than 2 weight percent of total polymer units derived from acrylic acid, no more than 10 weight percent of total polymer units derived from acrylonitrile, no more than 2 weight percent of total polymer units derived from N-methylolacrylamide, and no more than 25 weight percent of total polymer units derived from styrene. For use only as provided in paragraph (m) of this section. Melamine-formaldehyde. Melamine-formaldehyde chemically modified with one or more of the amine catalysts identified in § 175.300(b)(3)(xiii) of this chapter. Melamine-formaldehyde chemically modified with methyl alcohol. Melamine-formaldehyde chemically modified with urea; for use only as provided for in paragraphs (e), (f), (g), (h), and (i) of this section. Phenol-formaldehyde resins. Polyvinyl alcohol. Polyvinyl alcohol with the copolymer of acrylic acid-allyl sucrose. Polyvinyl alcohol with melamine formaldehyde. Polyvinyl acetate with melamine formaldehyde. p--Toluenesulfonamide-formaldehyde chemically modified with one or more of the amine catalysts identified in § 175.300 (b)(3)(xiii) of this chapter.

(4) Adjuvant substances:

Dimethyl polysiloxane with methylcellulose and sorbic acid (as an antifoaming agent). Phosphoric acid.

(5) Colorants: Colorants used in accordance with § 178.3297 of this chapter.

(e) Resin-bonded filters conforming with the specifications of paragraph (e) (1) of this section are used as provided in paragraph (e)(2) of this section:

(1) Total extractives. The finished filter, when exposed to distilled water at 100 °F for 2 hours, yields total extractives not to exceed 2.8 percent by weight of the filter.

(2) Conditions of use. It is used to filter milk or potable water at operating temperatures not to exceed 100 °F.

(f) Resin-bonded filters conforming with the specifications of paragraph (f) (1) of this section are used as provided in paragraph (e)(2) of this section:

(1) Total extractives. The finished filter, when exposed to distilled water at 145 °F for 2 hours, yields total extractives not to exceed 4 percent by weight of the filter.

(2) Conditions of use. It is used to filter milk or potable water at operating temperatures not to exceed 145 °F.

(g) Resin-bonded filters conforming with the specifications of paragraph (g) (1) of this section are used as provided in paragraph (g)(2) of this section:

(1) Total extractives. The finished filter, when exposed to n-hexane at reflux temperature for 2 hours, yields total extractives not to exceed 0.5 percent by weight of the filter.

(2) Conditions of use. It is used to filter edible oils.

(h) Resin-bonded filters conforming with the specifications of paragraph (h) (1) of this section are used as provided in paragraph (h)(2) of this section:

(1) Total extractives. The finished filter, when exposed to distilled water at 212 °F for 2 hours, yields total extractives not to exceed 4 percent by weight of the filter.

(2) Conditions of use. It is used to filter milk, coffee, tea, and potable water at temperatures not to exceed 212 °F.

(i) Resin-bonded filters conforming with the specifications of paragraph (i) (1) of this section are used as provided in paragraph (i)(2) of this section:

(1) Total extractives. The finished filter, when exposed to distilled water for 2 hours at a temperature equivalent to, or higher than, the filtration temperature of the aqueous food, yields total extractives not to exceed 4 percent, by weight, of the filter.

(2) Conditions of use. It is used in commercial filtration of bulk quantities of nonalcoholic, aqueous foods having a pH above 5.0.

(j) Resin-bonded filters conforming with the specifications of paragraph (j) (1) of this section are used as provided in paragraph (j)(2) of this section:

(1) Total extractives. The finished filter, when exposed to 5 percent (by weight) acetic acid for 2 hours at a temperature equivalent to, or higher than, the filtration temperature of the aqueous food, yields total extractives not to exceed 4 percent, by weight, of the filter.

(2) Conditions of use. It is used in commercial filtration of bulk quantities of nonalcoholic, aqueous foods having a pH of 5.0 or below.

(k) Resin-bonded filters conforming with the specifications of paragraph (k) (1) of this section are used as provided in paragraph (k)(2) of this section:

(1) Total extractives. The finished filter, when exposed to 8 percent (by volume) ethyl alcohol in distilled water for 2 hours at a temperature equivalent to, or higher than, the filtration temperature of the alcoholic beverage, yields total extractives not to exceed 4 percent, by weight, of the filter.

(2) Conditions of use. It is used in commercial filtration of bulk quantities of alcoholic beverages containing not more than 8 percent alcohol.

(l) Resin-bonded filters conforming with the specifications of paragraph (l) (1) of this section are used as provided in paragraph (l)(2) of this section:

(1) Total extractives. The finished filter, when exposed to 50 percent (by volume) ethyl alcohol in distilled water for 2 hours at a temperature equivalent to, or higher than, the filtration temperature of the alcoholic beverage, yields total extractives not to exceed 4 percent, by weight, of the filter.

(2) Conditions of use. It is used in commercial filtration of bulk quantities of alcoholic beverages containing more than 8 percent alcohol.

(m) Resin-bonded filters fabricated from acrylic polymers as provided in paragraph (d)(3) of this section together with other substances as provided in paragraph (d), (1), (2), and (4) of this section may be used as follows:

(1) The finished filter may be used to filter milk or potable water at operating temperatures not to exceed 100 °F, provided that the finished filter when exposed to distilled water at 100 °F for 2 hours yields total extractives not to exceed 1 percent by weight of the filter.

(2) The finished filter may be used to filter milk or potable water at operating temperatures not to exceed 145 °F, provided that the finished filter when exposed to distilled water at 145 °F for 2 hours yields total extractives not to exceed 1.2 percent by weight of the filter.

(n) Acrylonitrile copolymers identified in this section shall comply with the provisions of § 180.22 of this chapter.

[42 FR 14572, Mar. 15, 1977, as amended at 56 FR 42933, Aug. 30, 1991]