§178.3850 Reinforced wax
Reinforced wax may be safely used as an article or component of articles intended for use in producing, manufacturing, packing, processing, transporting, or holding food subject to the provisions of this section.
（a） Reinforced wax consists of petroleum wax to which have been added certain optional substances required in its production, or added to impart desired physical or technical properties.
（b） The quantity of any optional adjuvant substance employed in the production of or added to reinforced wax does not exceed the amount reasonably required to accomplish the intended physical or technical effect or any limitation provided in this section.
（c） Any substance employed in the production of reinforced wax, including any optional substance, 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） The substances and optional adjuvant substances employed in the production of or added to reinforced wax include:
（1） Substances generally recognized as safe in food.
（2） Substances subject to prior sanction for use in reinforced wax and used in accordance with such sanction or approval.
（3） Substances identified in this subparagraph and subject to any limitations provided therein:
| List of substances | Limitations |
| Copolymer of isobutylene modified with isoprene | |
| Petroleum wax, Type I and Type II | |
| Polyethylene | |
| Rosins and rosin derivatives as provided in § 178.3870 | |
| Synthetic wax polymer as described in § 176.170(a)(5) of this chapter | Not to exceed 5 percent by weight of the petroleum wax. |
（e） Reinforced wax conforming with the specifications in this paragraph is used as provided in paragraph （e）（2） of this section.
（1） The chloroform-soluble portion of the water extract obtained by exposing reinforced wax to demineralized water at 70 °F for 48 hours shall not exceed 0.5 milligram per square inch of food-contact surface.
（2） It is used as a packaging material or component of packaging materials for cheese and cheese products.
[42 FR 14609, Mar. 15, 1977, as amended at 47 FR 1288, Jan. 12, 1982]
