[Code of Federal Regulations]
[Title 21, Volume 3]
[Revised as of April 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR178.3770]
[Page 415-420]
TITLE 21--FOOD AND DRUGS
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN
SERVICES (CONTINUED)
PART 178--INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS--Table of Contents
Subpart D--Certain Adjuvants and Production Aids
Sec. 178.3770 Polyhydric alcohol esters of oxidatively refined (Gersthofen process) montan wax acids.
Polyhydric alcohol esters of oxidatively refined (Gersthofen
process) montan wax acids identified in this section may be safely used
as components of articles intended for use in contact with food in
accordance with the following prescribed conditions:
(a) The polyhydric alcohol esters identified in this paragraph may
be used as lubricants in the fabrication of vinyl chloride plastic food-
contact articles prepared from polyvinyl chloride and/or from vinyl
chloride copolymers complying with Sec. 177.1980 of this chapter. Such
esters meet the following specifications and are produced by partial
esterification of oxidatively refined (Gersthofen process) montan wax
acids by either ethylene glycol or 1,3-butanediol with or without
neutralization of unreacted carboxylic groups with calcium hydroxide:
(1) Dropping point 76 deg.-105 deg.C, as determined by ASTM method
D566-76 (Reapproved 1982), ``Standard Test Method for Dropping Point of
Lubricating Grease,'' which is incorporated by reference. Copies may be
obtained from the American Society for Testing Materials, 1916 Race St.,
Philadelphia, PA 19103, or may be examined at the Office of the Federal
Register, 800 North Capitol Street, NW., suite 700, Washington, DC
20408.
(2) Acid value 10-20, as determined by ASTM method D1386-78
(``Standard Test Method for Acid Number (Empirical) of Synthetic and
Natural Waxes'' (Revised 1978), which is incorporated by reference;
copies are available from American Society for Testing and Materials
(ASTM), 1916 Race Street, Philadelphia, PA 19103, or available for
inspection at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC 20408) using as solvent xylene-
ethyl alcohol in a 2:1 ratio instead of toluene-ethyl alcohol in a 2:1
ratio.
(3) Saponification value 100-160, as determined by ASTM method
D1387-78 (``Standard Test Method for Saponification Number (Empirical)
of Synthetic and Natural Waxes'' (Revised 1978), which is incorporated
by reference; copies are available from American Society for Testing and
Materials (ASTM), 1916 Race Street, Philadelphia, PA 19103, or available
for inspection at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC 20408) using xylene-ethyl alcohol
in a 2:1 ratio instead of ethyl alcohol in preparation of potassium
hydroxide solution.
(4) Ultraviolet absorbance limits as follows, as determined by the
analytical method described in this subparagraph:
Ultraviolet absorbance per centimeter pathlength.
------------------------------------------------------------------------
Millimicrons Maximum
------------------------------------------------------------------------
280 to 289.................................................. 0.07
290 to 299.................................................. .06
300 to 359.................................................. .04
360 to 400.................................................. .01
------------------------------------------------------------------------
Analytical Method
general instructions
Because of the sensitivity of the test, the possibility of errors
arising from contamination is great. It is of the greatest importance
that all glassware be scrupulously cleaned to remove all organic matter
such as oil, grease, detergent residues, etc. Examine all glassware,
including stoppers and stopcocks, under ultraviolet light to detect any
residual fluorescent contamination. As a precautionary measure it is
recommended practice to rinse all glassware with purified isooctane
immediately before use. No grease is to be used on stopcocks or joints.
Great care to avoid contamination of wax samples in handling and to
assure absence of any extraneous material arising from inadequate
packaging is essential. Because some of the polynuclear hydrocarbons
sought in this test are very susceptible to photo-oxidation, the entire
procedure is to be carried out under subdued light.
apparatus
Separatory funnels. 250-milliliter, 500-milliliter, 1,000-
milliliter, and preferably 2,000-milliliter capacity, equipped with
tetrafluoroethylene polymer stopcocks.
Reservoir. 1,000-milliliter capacity, equipped with a 24/40 standard
taper male fitting at the bottom and a suitable balljoint at the top.
Chromatographic tube. 1,200 millimeters in length, inside diameter
to be 16.5 millimeters plus-minus0.5 millimeter, equipped
with a coarse, fritted-glass disc, a tetrafluoroethylene polymer
stopcock, and a female 24/40 standard tapered fitting at the opposite
end. (Overall length of
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the column with the female joint is 1,255 millimeters.) The female
fitting should be equipped with glass hooks.
Disc. Tetrafluoroethylene polymer 2-inch diameter disc approximately
\3/16\-inch thick with a hole bored in the center to closely fit the
stem of the chromatographic tube.
Heating jackets. Conical, for 500-milliliter and 1,000-milliliter
separatory funnels. (Used with variable transformer heat control.)
Suction flask. 250-milliliter or 500-milliliter filter flask.
Condenser. \24/40\ joints, fitted with a drying tube, length
optional.
Evaporation flasks (optional). A 250-milliliter or 500-milliliter
capacity and a 1-liter capacity all-glass flask equipped with standard
taper stopper having inlet and outlet tubes to permit passage of
nitrogen across the surface of contained liquid to be evaporated.
Vacuum distillation assembly. All glass (for purification of
dimethyl sulfoxide) 2-liter distillation flask with heating mantle;
Vigreaux vacuum-jacketed condenser (or equivalent) about 45 centimeters
in length and distilling head with separable cold finger condenser. Use
of tetrafluoroethylene polymer sleeves on the glass joints will prevent
freezing. Do not use grease on stopcocks or joints.
Oil bath. Capable of heating to 90 deg.C.
Spectrophotometric cells. Fused quartz cells, optical pathlength in
the range 1.000 centimeter plus-minus0.005 centimeter. With
distilled water in the cells, determine any absorbance differences.
Spectrophotometer. Spectral range 250 millimicrons-400 millimicrons
with spectral slit width of 0.2 millimicron or less; under instrument
operating conditions for these absorbance measurements. The
spectrophotometer shall also meet the following performance
requirements:
Absorbance repeatability, plus-minus0.01 at 0.4
absorbance.
Absorbance accuracy, \1\ plus-minus0.05 at 0.4
absorbance.
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\1\ As determined by procedure using potassium chromate for
reference standard and described in National Bureau of Standards
Circular 484, Spectrometry, U.S. Department of Commerce (1949). The
accuracy is to be determined by comparison with the standard values at
290, 345, and 400 millimicrons. Circular 484 is incorporated by
reference. Copies are available from the Center for Food Safety and
Applied Nutrition (HFS-200), Food and Drug Administration, 200 C St.
SW., Washington, DC 20204, or available for inspection at the Office of
the Federal Register, 800 North Capitol Street, NW., suite 700,
Washington, DC 20408.
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Wavelength repeatability, plus-minus0.2 millimicron.
Wavelength accuracy, plus-minus1.0 millimicron.
Recording time, 50 seconds.
Time constant, 0.6 second.
Sensitivity, 30.
Ordinate scale, 90-100 percent transmission through scale.
Abscissa scale, 8X.
Nitrogen cylinder. Water-pumped or equivalent purity nitrogen in
cylinder equipped with regulator and valve to control flow at 5 p.s.i.g.
reagents and materials
Organic solvents. All solvents used throughout the procedure shall
meet the specifications and tests described in this specification. The
isooctane and benzene designated in the list following this paragraph
shall pass the following test:
To be specified quantity of solvent in a 250-milliliter Erlenmeyer
flask, add 1 milliliter of purified n-hexadecane and evaporate on the
steam bath under a stream of nitrogen (a loose aluminum foil jacket
around the flask will speed evaporation). Discontinue evaporation when
not over 1 milliliter of residue remains. (To the residue from benzene
add a 10-milliliter portion of purified isooctane, reevaporate, and
repeat once to insure complete removal of benzene.)
Alternatively, the evaporation time can be reduced by using the
optional evaporation flask. In this case the solvent and n-hexadecane
are placed in the flask on the steam bath, the tube assembly is
inserted, and a stream of nitrogen is fed through the inlet tube while
the outlet tube is connected to a solvent trap and vacuum line in such a
way as to prevent any flow-back of condensate into the flask.
Dissolve the 1 milliliter of hexadecane residue in isooctane and
make up to 25 milliliters volume. Determine the absorbance in the 1-
centimeter pathlength cells compared to isooctane as reference. The
absorbance of the solution of the solvent residue (except for methyl
alcohol) shall not exceed 0.01 per centimeter pathlength between 280
m and 400 m.
Isooctane (2,2,4-trimethylpentane). Use 180 milliliters for the test
described in the preceding paragraph. Purify, if necessary, by passage
through a column of activated silica gel (Grade 12, Davison Chemical
Co., Baltimore, Md., or equivalent) about 90 centimeters in length and 5
centimeters to 8 centimeters in diameter.
Benzene, A.C.S. reagent grade. Use 150 milliliters for the test.
Purify, if necessary, by distillation or otherwise.
n-Hexadecane, 99 percent olefin-free. Dilute 1.0 milliliter of n-
hexadecane to 25 milliliters with isooctane and determine the absorbance
in a 1-centimeter cell compared to isooctane as reference point between
280 m-400 m. The absorbance per centimeter pathlength
[[Page 417]]
shall not exceed 0.00 in this range. If necessary, purify by filtering
through a column containing 100 grams of aluminum oxide (use same grade
as described below) in the lower half and 100 grams of activated silica
gel in the upper half keeping the column at 150 deg.C., for a period of
15 hours or overnight. The first 100 milliliters of eluate are used.
Purification can also be accomplished by distillation.
Dimethyl sulfoxide. Pure grade, clear, water-white, m.p. 18 deg.
minimum. Dilute 120 milliliters of dimethyl sulfoxide with 240
milliliters of distilled water in a 500-milliliter separatory funnel,
mix and allow to cool for 5-10 minutes. Add 40 milliliters of isooctane
to the solution and extract by shaking the funnel vigorously for 2
minutes. Draw off the lower aqueous layer into a second 500-milliliter
separatory funnel and repeat the extraction with 40 milliliters of
isooctane. Draw off and discard the aqueous layer. Wash each of the 40-
milliliter extractives three times with 50-milliliter portions of
distilled water. Shaking time for each wash is 1 minute. Discard the
aqueous layers. Filter the first extractive through anhydrous sodium
sulfate prewashed with isooctane (see Sodium sulfate under ``Reagents
and materials'' for preparation of filter), into a 250-milliliter
Erlenmeyer flask, or optionally into the evaporating flask. Wash the
first separatory funnel with the second 40-milliliter isooctane
extractive, and pass through the sodium sulfate into the flask. Then
wash the second and first separatory funnels successively with a 10-
milliliter portion of isooctane, and pass the solvent through the sodium
sulfate into the flask. Add 1 milliliter of n-hexadecane and evaporate
the isooctane on the steam bath under nitrogen. Discontinue evaporation
when not over 1 milliliter of residue remains. To the residue, add a 10-
milliliter portion of isooctane and reevaporate to 1 milliliter of
hexadecane. Again, add 10 milliliters of isooctane to the residue and
evaporate to 1 milliliter of hexadecane to insure complete removal of
all volatile materials. Dissolve the 1 milliliter of hexadecane in
isooctane and make to 25-milliliter volume. Determine the absorbance in
1-centimeter pathlength cells compared to isooctane as reference. The
absorbance of the solution should not exceed 0.02 per centimeter
pathlength in the 280 m-400 m range. (Note: Difficulty
in meeting this absorbance specification may be due to organic
impurities in the distilled water. Repetition of the test omitting the
dimethyl sulfoxide will disclose their presence. If necessary to meet
the specification, purify the water by redistillation, passage through
an ion-exchange resin, or otherwise.)
Purify, if necessary, by the following procedure: To 1,500
milliliters of dimethyl sulfoxide in a 2-liter glass-stoppered flask,
add 6.0 milliliters of phosphoric acid and 50 grams of Norit A
(decolorizing carbon, alkaline) or equivalent. Stopper the flask, and
with the use of a magnetic stirrer (tetrafluoroethylene polymer coated
bar) stir the solvent for 15 minutes. Filter the dimethyl sulfoxide
through four thicknesses of fluted paper (18.5 centimeters, Schleicher &
Schuell, No. 597, or equivalent). If the initial filtrate contains
carbon fines, refilter through the same filter until a clear filtrate is
obtained. Protect the sulfoxide from air and moisture during this
operation by covering the solvent in the funnel and collection flask
with a layer of isooctane. Transfer the filtrate to a 2-liter separatory
funnel and draw off the dimethyl sulfoxide into the 2-liter distillation
flask of the vacuum distillation assembly and distill at approximately
3-millimeter Hg pressure or less. Discard the first 200-milliliter
fraction of the distillate and replace the distillate collection flask
with a clean one. Continue the distillation until approximately 1 liter
of the sulfoxide has been collected.
At completion of the distillation, the reagent should be stored in
glass-stoppered bottles since it is very hygroscopic and will react with
some metal containers in the presence of air.
Phosphoric acid. 85 percent A.C.S. reagent grade.
Aluminum oxide (80-200 mesh Woelm neutral activity grade 1
[Brockmann], Alupharm Chemicals, New Orleans, La., or equivalent).
Pipette 1 milliliter of distilled water into a dry 250-milliliter
Erlenmeyer flask equipped with a ground-glass stopper. Stopper the flask
and rotate it in such a manner as to completely wet out the inside
surfaces. When this has been done add 180 grams of the aluminum oxide
and shake until no lumps or wet spots remain. Allow to stand at room
temperature for a period of 2 hours. At the end of this time the water
should be evenly distributed throughout the aluminum oxide powder, and
it should have the same free flowing properties as the original material
(flow velocity with water 0.2 milliliter per minute). At this point the
aluminum oxide has an activity of 1 as expressed in Brockmann degrees,
and the amount of added water is 0.5 percent by volume. This product is
used in toto and as is, without further screening.
Sodium sulfate, anhydrous, A.C.S. reagent grade, preferably in
granular form. For each bottle of sodium sulfate reagent used, establish
as follows the necessary sodium sulfate prewash to provide such filters
required in the method: Place approximately 35 grams of anhydrous sodium
sulfate in a 30-milliliter coarse, fritted-glass funnel or in a 65-
millimeter filter funnel with glass wool plug; wash with successive 15-
milliliter portions of the indicated solvent until a 15-milliliter
portion of the wash shows 0.00 absorbance per centimeter pathlength
between 280 m and 400 m when tested as prescribed
under
[[Page 418]]
``Organic solvents.'' Usually three portions of wash solvent are
sufficient.
procedure
Before proceeding with analysis of a sample, determine the
absorbance in a 1-centimeter path cell between 250 m and 400
m for the reagent blank by carrying out the procedure, without
a wax sample, at room temperature, recording the spectrum after the
complete procedure as prescribed. The absorbance per centimeter
pathlength following the complete procedure should not exceed 0.04 in
the wavelength range from 280 m to 299 m, inclusive,
nor 0.02 in the wavelength range from 300 m to 400 m.
If in either spectrum the characteristic benzene peaks in the 250
m-260 m region are present, remove the benzene by the
procedure under ``Organic solvents'' and record absorbance again. Place
300 milliliters of dimethyl sulfoxide in a 1-liter separatory funnel and
add 75 milliliters of phosphoric acid. Mix the contents of the funnel
and allow to stand for 10 minutes. (The reaction between the sulfoxide
and the acid is exothermic. Release pressure after mixing, then keep
funnel stoppered.) Add 150 milliliters of isooctane and shake to
preequilibrate the solvents. Draw off the individual layers and store in
glass-stoppered flasks.
In a 1-liter separatory funnel place a representative 25-gram sample
of wax, add 50 milliliters of isooctane, heat gently, stir until the wax
is in solution; add 100 milliliters of preequilibrated sulfoxide-
phosphoric acid mixture and shake, making sure it remains in solution.
If the wax comes out of solution during these operations, let the
stoppered funnel remain in the jacket until the wax redissolves. (Remove
stopper from the funnel at intervals to release pressure.) When the wax
is in solution, remove the funnel from the jacket and shake it
vigorously for 2 minutes. Set up three 250-milliliter separatory funnels
with each containing 30 milliliters of preequilibrated isooctane. After
separation of the liquid phases, allow to cool until the main portion of
the wax-isooctane solution begins to show a precipitate. Gently swirl
the funnel when precipitation first occurs on the inside surface of the
funnel to accelerate this process. Carefully draw off the lower layer,
filter it slowly through a thin layer of glass wool fitted loosely in a
filter funnel into the first 250-milliliter separatory funnel, and wash
in tandem with the 30-milliliter portions of isooctane contained in the
250-milliliter separatory funnels. Shaking time for each wash is 1
minute. Repeat the extraction operation with two additional portions of
the sulfoxide-acid mixture, replacing the funnel in the jacket after
each extraction to keep the wax in solution and washing each extractive
in tandem through the same three portions of isooctane.
Collect the successive extractives (300 milliliters total) in a
separatory funnel (preferably 2-liter), containing 480 milliliters of
distilled water, mix, and allow to cool for a few minutes after the last
extractive has been added. Add 80 milliliters of isooctane to the
solution and extract by shaking the funnel vigorously for 2 minutes.
Draw off the lower aqueous layer into a second separatory funnel
(preferably 2-liter) and repeat the extraction with 80 milliliters of
isooctane. Draw off and discard the aqueous layer. Wash each of the 80-
milliliter extractives three times with 100-milliliter portions of
distilled water. Shaking time for each wash is 1 minute. Discard the
aqueous layers. Filter the first extractive through anhydrous sodium
sulfate prewashed with isooctane (see Sodium sulfate under ``Reagents
and Materials'' for preparation of filter) into a 250-milliliter
Erlenmeyer flask (or optionally into the evaporation flask). Wash the
first separatory funnel with the second 80-milliliter isooctane
extractive and pass through the sodium sulfate. Then wash the second and
first separatory funnels successively with a 20-milliliter portion of
isooctane and pass the solvent through the sodium sulfate into the
flask. Add 1 milliliter of n-hexadecane and evaporate the isooctane
using an aspirator vacuum under nitrogen and in an oil bath temperature
of approximately 90 deg.C. Discontinue evaporation when not over 1
milliliter of residue remains. To the residue, add a 10-milliliter
portion of isooctane, reevaporate to 1 milliliter of hexadecane, and
repeat this operation once.
Reserve the residue for column chromatography on the aluminum oxide.
Fit the tetrafluoroethylene polymer disc on the upper part of the stem
of the chromatographic tube, then place the tube with the disc on the
suction flask and apply the vacuum (approximately 135 millimeters Hg
pressure). Weigh out 180 grams of the aluminum oxide and pour the
adsorbent mixture into the chromatographic tube in approximately 30-
centimeter layers. After the addition of each layer, level off the top
of the adsorbent with a flat glass rod or metal plunger by pressing down
firmly until the adsorbent is well packed. Loosen the topmost few
millimeters of each adsorbent layer with the end of a metal rod before
the addition of the next layer. Continue packing in this manner until
all the 180 grams of the adsorbent is added to the tube. Level off the
top of the adsorbent by pressing down firmly with a flat glass rod or
metal plunger to make the depth of the adsorbent bed approximately 80
centimeters in depth. Turn off the vacuum and remove the suction flask.
Dissolve the hexadecane residue in 10 milliliters of warm benzene and
decant the solution onto the column and allow the liquid level to recede
to barely above the adsorbent level. Rapidly complete the transfer
similarly with two 10-
[[Page 419]]
milliliter portions of benzene swirling the flask repeatedly each time
to assure adequate washing of the residue. Fix the 1,000-milliliter
reservoir onto the top of the chromatographic column. Just before the
final 10-milliliter wash reaches the top of the adsorbent, add 670
milliliters of benzene to the reservoir and continue the percolation at
the 2-3 milliliter per minute rate until a total of 670 milliliters of
benzene has been utilized. Collect the eluate in a clean 1-liter
Erlenmeyer flask (or optionally into a 1-liter evaporation flask). Allow
the column to drain until most of the solvent mixture is removed. Add 1
milliliter of n-hexadecane and completely remove the benzene by
evaporation under nitrogen, using the special procedure to eliminate
benzene as previously described under ``Organic Solvents.''
Quantitatively transfer the residue with isooctane to a 25-milliliter
volumetric flask and adjust to volume. Determine the absorbance of the
solution in the 1-centimeter pathlength cells compared to isooctane as
reference between 250 m-400 m. Correct for any
absorbance derived from the reagents as determined by carrying out the
procedure without a wax sample. If either spectrum shows the
characteristic benzene peaks in the 250 m-260 m
region, evaporate the solution to remove benzene by the procedure under
``Organic Solvents.'' Dissolve the residue, transfer quantitatively, and
adjust to volume in isooctane in a 25-milliliter volumetric flask.
Record the absorbance again. If the corrected absorbance does not exceed
the limits prescribed in paragraph (a) of this section, the wax meets
the ultraviolet absorbance specifications.
(b) The polyhydric alcohol esters identified in this paragraph may
be used as release agents in resinous and polymeric coatings for
polyolefin films complying with Sec. 175.320 of this chapter. Such
esters meet the following specifications and are produced by partial
esterification of oxidatively refined (Gersthofen process) montan wax
acids with equimolar proportions of ethylene glycol and 1,3-butanediol:
(1) Dropping point 77 deg.-82 deg.C, as determined by ASTM method
D566-76 (Reapproved 1982), ``Standard Test Method for Dropping Point of
Lubricating Grease,'' which is incorporated by reference. The
availability of this incorporation by reference is given in paragraph
(a)(1) of this section.
(2) Acid value 25-35, as determined by ASTM method D1386-78
(``Standard Test Method for Acid Number (Empirical) of Synthetic and
Natural Waxes'' (Revised 1978), which is incorporated by reference;
copies are available from American Society for Testing and Materials
(ASTM), 1916 Race Street, Philadelphia, PA 19103, or available for
inspection at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC 20408) using as solvent xylene-
ethyl alcohol in a 2:1 ratio instead of toluene-ethyl alcohol in a 1:2
ratio.
(3) Saponification value 135-150, as determined by ASTM method
D1387-78 (``Standard Test Method for Saponification Number (Empirical)
of Synthetic and Natural Waxes'' (Revised 1978), which is incorporated
by reference; copies are available from American Society for Testing and
Materials (ASTM), 1916 Race Street, Philadelphia, PA 19103, or available
for inspection at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC 20408) using xylene-ethyl alcohol
in a 2:1 ratio instead of ethyl alcohol in preparation of potassium
hydroxide solution.
(4) Ultraviolet absorbance limits specified in paragraph (a)(4) of
this section, as determined by the analytical method described therein.
(c) The polyhydric alcohol esters of oxidatively refined (Gersthofen
process) montan wax acids, identified in paragraph (a) or (b) of this
section, may also be used as a component of an aqueous dispersion of
vinylidene chloride copolymers, subject to the conditions described in
paragraphs (c) (1) and (2) of this section.
(1) The aqueous dispersion of the additive contains not more that 18
percent polyhydric alcohol esters of oxidatively refined (Gersthofen
process) montan wax acids, not more than 2 percent poly(oxyethylene)
(minimum 20 moles of ethylene oxide) oleyl ether (CAS Reg. No. 9005-98-
2), and not more than 1 percent poly(oxyethylene) (minimum 3 moles
ethylene oxide) cetyl alcohols (CAS Reg. No. 9004-95-9).
(2) The aqueous dispersion described in paragraph (c)(1) of this
section is used as an additive to aqueous dispersions of vinylidene
chloride copolymers, regulated in Secs. 175.300, 175.320, 175.360,
176.170, 176,180, and 177.1630 of this chapter, at levels not to exceed
1.5 percent (solids basis) in the finished coating.
[[Page 420]]
(d) The polyhydric alcohol esters identified in this paragraph may
be used as lubricants in the fabrication of vinyl chloride plastic food
contact articles prepared from vinyl chloride polymers. Such esters meet
the following specifications and are produced by partial esterification
of oxidatively refined (Gersthofen process) montan wax acids with
glycerol followed by neutralization:
(1) Dropping point 79 to 85 deg.C, as determined by the American
Society for Testing and Materials (ASTM), Method D-566-76 (Reapproved
1982), ``Standard Test Method for Dropping Point of Lubricating
Grease,'' which is incorporated by reference in accordance with 5 U.S.C.
552(a). The availability of this incorporation by reference is given in
paragraph (a)(1) of this section.
(2) Acid value 20-30, as determined by ASTM Method D-1386-78
``Standard Test Method for Acid Number (Empirical) of Synthetic and
Natural Waxes'' (Revised 1978) (which is incorporated by reference in
accordance with 5 U.S.C. 552(a); the availability of this incorporation
by reference is given in paragraph (a)(2) of this section), using as a
solvent xylene-ethyl alcohol in a 2:1 ratio instead of toluene-ethyl
alcohol in a 2:1 ratio.
(3) Saponification value 130-160, as determined by ASTM Method D-
1387-78 ``Standard Test Method for Saponification Number (Empirical) of
Synthetic and Natural Waxes'' (Revised 1978), (which is incorporated by
reference in accordance with 5 U.S.C. 552(a); the availability of this
incorporation by reference is given in paragraph (a)(3) of this
section), using xylene-ethyl alcohol in a 2:1 ratio instead of ethyl
alcohol in the preparation of potassium hydroxide solution.
(4) Ultraviolet absorbance limits specified in paragraph (a)(4) of
this section, as determined by the analytical method described therein.
[42 FR 14609, Mar. 15, 1977, as amended at 47 FR 11848, Mar. 19, 1982;
49 FR 10113, Mar. 19, 1984; 51 FR 33895, Sept. 24, 1986; 54 FR 24898,
June 12, 1989; 55 FR 28020, July 9, 1990; 58 FR 17512, Apr. 5, 1993]