Product Design
Quarterly Section Research Report
Abstract
Summarizes second quarter 1973 research activities including: smoke pH, smoke pH control factors, improvements to G-7 [reconstituted tobacco], comparisons of physical characteristics of Marlboro vs Winston, pH of pipe smoke, physical properties of smoke, smoke formation, air dilution, filtration and the use of tobacco extenders [popcorn]. Says pH and sales data of competitive brands have been analyzed [1957-72], new pH data of the top 20 filter cigarettes obtained, free nicotine calculated and states "There was an apparent correlation between the calculated free nicotine and cigarette sales". Indicates there is a new effort to determine the factors of controlling smoke pH and notes the location and amount of casing is a significant factor in manipulating smoke pH while minimizing the effects on taste and flavor. Indicates increased nicotine transfer with high pH burley, puff-by puff studies of butt length and dilution are being analyzed and molded air dilution filters [MAD-F], fiber filters, open and closed cell foam filters and COLLO-Sanilan filters are being studied. Says ground popcorn is being evaluated as a new tobacco extender as it has high filling capacity, low density, little effect on burning tobacco and at lower levels [<12.5%] "there is no detectable difference in mainstream smoke."
Fields
- Notes
Popcorn is being evaluated as an tobacco extender [p6].
- Author
- *Piehl, D.H. (use Piehl, Donald H.)RJR, Manager Chemical
- Recipient
- Rodgman, F. Alan (RJR Fundamental Research Director)Senior Research Chemist 1954-1965, Head of the Smoke Research Section 1965-1975, Manager of Analytic Research 1975-1976, Director of Research 1976-1980, Director of the Chemical Division 1980-1983, Director of Fundamental R&D 1985-1987.
Changes in cigarette design over the past half century.
Modification of selected mainstream smoke constituents in response to health concerns.
Design changes which alter nicotine delivery or effect how the product causes and maintains dependence, including transfer of nicotine from tobacco to smoke, and uptake into the body.
Development of methods for measurement of gas and particulate yields in mainstream and sidestream smoke.
Modification of tobacco products through use of filters, paper, and ventilation, and measuring effects on dependence, behavior, and toxicity.
Modification of tobacco products through changes in tobacco processing and use of blends, and measuring effects on dependence, behavior, and toxicity.
Technologies used to measure, control, or alter sensory effects
Acidity/ baseness, scale from 0-14, 7 neutral
Total nicotine in the unburnt tobacco rod
Document Images
Author: Donald H. Piehl June 13, 1973
Physical Chemistry Section
Chemical Division
To: Dr. Alan Rodgman Period Covered: April 1, 1973 -
A/Manager, Chemical Division June 30, 1973
Re: QUARTERLY SECTION RESEARCH REPORT No. of Pages: 7
BASIC STUDY - SMOKE BALANCE AND CONTROL (Project 1210, Woods)
I. Smoke pH Studies (Woods, Harllee, Ha;rris)
Thorough evaluation of a specially designed ten-port cigarette smoking
machine and modified pH method was completed., Smoke pH measurements of ten
cigarettes are recorded continually as a single plot which eliminates the pH
shifts which normally occur between puffs. Values for 30 competitive brands
showed good agreement with average values-obi~ained by multiple determinations
using the standard method. The biggest advantage of the modified technique is ..
speed in that a reliable pH value can be obtained in almost the same time it
takes to smoke a single cigarette. However,,it is necessary to precondition k, J
the electrodes with smoke of the sample to bg tested.
A twenty-port smoking machine has now been designed and constructed for
use in smoke pH measurements. This system will allow the same rapid and
reliable analysis found for the ten-port machine as well as eliminating the
necessity for preconditioning of the electrodes. This system will be
evaluated as soon as additional parts are received.
A comprehensive study of historical pH'and sales data was completed in
preparation for an executive management presentation. Data on several
competitive brands were compiled from numerous departmental sources for the
years 1957-72. Additional new smoke pH data were obtained for the top twenty
filtered cigarette brands using the modified ten-port technique. Free nicotine
calculations were made from nicotine and smoke pH data and numerous graphs
plotted. There was an apparent correlation!between the calculated free nicotine
and cigarette sales for the years studied. Results are reported in RDM, 1972,
No. 16.
II. Smoke pH Control Factors
As a result of important new findings and management decision,a more
intensive effort is underway to determine the factors which control smoke pH.
It has been demonstrated that the amount and location of casing materials in the
blend is one of the most important controlling factors. Also, as demonstrated
previously, chemical additives can be used for pH control. The total influence
of ammonia on smoke pH is under investigation. It is anticipated that as all
the factors are identified a combination or;systems approach to pH control will
be undertaken. The obj ective is to provide; means to manipulate smoke pH at
will while minimizing the effect on overall flavor and taste.
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A summary of ailcur work to date has been provided to Tobacco Development.
New analyses for specific acids and bases are still under development in the
Analytical Division.
III. Improvement of Physical Characteristics of G-7
It has been shown that addition of 2% paraffin wax to G-7 before cutting
greatly reduces lamination and increases strand length and filling capacity.
However, a slight off-taste was imparted to the smoke. It is speculated that
the treatment is related to moisture uptake of the sheet. Lower additive levels
or similar treatments may prove to be just as effective without the accompanying
taste problem, but priority has not permitted pursual of this effort. It is
hoped that Research personnel more familiar with tobacco processes will continue
this work.
IV. Marlboro Versus WINSTON
As a result of discussions with Tobacco Development last quarter about
differences in the physical construction of Marlboro versus WINSTON cigarettes,
additional photographic measurements were made at their request. Samples were
examined to determine the effect of steam flotation on tobacco strand orientation
and packing in the cigarette as well the effect of packing characteristics on
wrinkling of the cigarette paper.
V. Smoking Tobaccos
A residual effort on smoking tobacco has'been intensified in an attempt to
get more information about the effect of smoke pH on pipe smoke quality. First
priority is being given to development of a rapid and accurate method for
measuring the pH of pipe smoke. A system has', been designed and is being
constructed. Experiments with cased stems and casing location are continuing
as well as additive treatments to reduce bite.
BASIC STUDY - FORMATION AND PHYSICAL PROPERTIES OF SMOKE (Project 1245, Woods)
I. Physical Properties of Smoke (Harrington)
Measurements reported last quarter showed that simulated oral deposition of
more volatile compounds, which comprise over'i90% of material transferred, results
almost entirely from an evaporative, molecula'r-diffusion process. However, the
data provided an incomplete description of nicotine and other less-volatile
compounds.
Using the same oral-cavity model (a 50-m,1 glass syringe), similarly prepared
samples of smoke-exposed water were analyzed'',,for total alkaloids using the Willits
UV-absorption method. Overall nicotine transfer was 3-8% (3-8 ug/puff) during
5-second exposures to the first three puffs of standard WINSTON smoke. Measurements
with totally-filtered smoke show that vapor-phase nicotine accounts for 1/7 of this.
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Measurements using a dry syringe demonstrate'that direct deposition via
particle movement accounts for nearly half of total nicotine transfer.
Notably,this second mechanism is non-selective, involving all of the
least volatile and water-insoluble compounds',which should be excluded by
the evaporative, molecular-diffusion process.
Increasing the age, and therefore, the particle size of the smoke
retards deposition via particulate migration'more than it reduces the
evaporative, molecular diffusion process. In principle this provides a
means to favor the more selective process over the non-selective one.
Increased nicotine transfer was demonstrated with two high pH
experimental burley tobaccos. In one case, 4 cigarette having tar and
nicotine levels similar to WINSTON exhibited,a nearly 6-fold increase in
transferred nicotine (29% transfer/5-sec.expdsure). In the other, a
low tar and nicotine burley cigarette (14.3 and 0.1 mg/cig., respectively)
transferred even more nicotine than WINSTON,',equivalent to 73% transfer
during 5-second exposures (a 15-fold percentage increase). A similar
effect has been noticed by other workers (Artho and Grob, 1970), but
only a two-fold difference in transfer was found between smoke having
pH values of 5 and 8.
The transfer is only slightly affected by variations in the area or
pH of exposed water, or by agitation, suggesting that the evaporative
process is limited more by the rate of particulate evaporation than by
vapor dissolving in exposed water. These results provide experimental
evidence for support of calculated free nicotine-pH relationships discussed
under smoke balance research, but also suggest total transfer of nicotine
may be pH dependent.
II. Smoke Formation Studies (Harris)
Only slight progress was made thisq.iart~r on smoke formation studies
as considerable effort was devoted to smoke pH methods.
Feasibility of a computerized multiple thermocouple approach to
temperature profile measurements in a burning cigarette has been established.
Equipment necessary to complete the system is being ordered.
AIR DILUTION AND FILTRATION (Project 1246, Stowe)
I. Basic Study of Air Dilution (Reynolds, Wheeler)
Three of the major experiments needed to provide basic information on
the mechanisms operative in air dilution systems were completed during this
quarter.
Using the argon tracer technique previoosly described for measuring the
amount of air dilution in a burning cigarette,a puff-by-puff study of the
effect of butt length on dilution was examined over a range of cigarette
dilution levels (3 to 80%). Oxygen consumption, CO, C02, and CH4 production
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as well as WTPM production were determined. Interpretation is not complete,
but it is apparent from these experiments that dilution does not change
appreciably from puff-to-puff for TC devices.'
Measurements were made to break down the' total puff volume of diluted
cigarettes into its component parts: (1) gas flow through air dilution
holes, (2) gas flow through cigarette paper, and (3) gas flow through fire
cone area. These studies were made using a r I ange of dilution levels from
3 to 80% on a per cigarette basis. Results indicate that the percentage of
the total puff volume entering through the paper (on a per cigarette basis)
ranges from 22% at a dilution level of about three percent to 12% at a
dilution level of about eighty perc ent.
Studies were made of WTPM, C0, C02, and CH4 production and oxygen
consumption using reduced puff volumes to simulate air dilution. Simulated
levels of dilution ranged from 3.4 to 79%, wh'ile puff volumes ranged from
33.8 to 7.4 ml. Data reduction and interpretation are incomplete, but the
effects of puff volume appear to be the same as the effects of dilution.
In addition to these experiments, preliminary work was done on the
n,easurement of pressure drop and flow profiles in TC-device cigarettes.
II. Filtration (Stowe, White, Reynolds, Wheeler)
A. TC-Device
Research on the TC-device has been',temporarily suspended and a
report is being prepared covering all work to date.
Assistance has been provided Tobacco Development on problems
associated with development of a molded'air dilution filter (MAD-F).
A problem of variation in filter performance was examined
(Sample L-6055-D) and it was revealed that filter efficiency was not
well controlled from filter to filter. Dilution was controlled within
acceptable limits, but since both dilution and filter efficiency act
to reduce tar in the MAD-F, the effect of variation in either factor
is enhanced by variation in the other factor. The result can be a
large variation in tar delivery. In this case the filter efficiency
was felt to be varying because of differences in the size of the
controlling smoke channel. This in turn was caused by variations in
the operation of the manual molding system. When the smoke channel
was fairly large, less smoke was exposed to the fibrous portion of
the filter and filter efficiency was low. The opposite situation
occurred when the channel was very narrow and in fact at times
narrow channels became blocked by small'pieces of tobacco resulting
in high filter efficiency. It was felt'by Tobacco Development that
the switch to fully automated molding systems would reduce the
observed variation.
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Tobacco Development requested that'a study be made of flow
patterns in the MAD-F system to determine the amount of smoke passing
through the smoke channel unfiltered. Since the smoke channel is not
a sealed passage, smoke is free to diffuse both in and out of the
channel making an accurate measurement almost impossible. However,
using the argon tracer technique designed for air dilution studies,
a means was devised to determine the percentage of the smoke which
entered the filter at the tobacco rod end of the smoke channel.
This was found to be about 45% of the smoke or about 25% of the
total puff volume. These representthe maximum values possible.
In another experiment smoke was drawn in at the smoke channel
and air through the fibrous portion of the filter resulting in
visible staining on the filter demonstrating the flow pattern.
It was evident that some smoke entering the smoke channel diffused
to and was removed by the fibrous portiqn of the filter.
B. Other Filtration Research
1._ Air Dilution Combined with Fiber Filtration (Reynolds, Wheeler)
Examination of various combinations of air dilution with fiber
filtration is underway. Factors being examined are placement of air
dilution orifices and mixing chambers.
2._ Open_Cell Foam Filter (White)
Dupont cellulose foam (open-cell) was tested as a filter
material. Filter efficiency was about 50% with or without air
dilution. Pressure drop was 2.8 inches of water without dilution
and 2.3 inches of water with dilution. No new open-celled foams
have been found to be commercially'available.
3._ Closed-Cell Foam Filter (White)
Closed-cell foams of PVC, polyethylene, and polypropylene
have been examined for heat molding properties for use in TC-type
configurations. Polyethylene and PVC foams did not heat form
well. Polypropylene showed the best heat molding properties, but
the sample tested has been discontinued by the manufacturer.
4._ COLLO-Sanilan (Stowe) I
COLLO-Sanilan is advertised as an air cleaning and deodorizing
medium with long life, low resistance to flow and suitable for room
temperature operation. It is an op'en-celled, hydrophilic foam
containing inorganic oxidation-reduction systems. Noxious components
are removed from air by effecting their complete oxidation. The
nature of the catalysts is not known. Cigarettes with the material
incorporated into the filter showed no unusual reductions in tar,
nicotine, CO, NOx, phenol, aldehydes, or HCN. I
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5._ Dev_elopment of Support Eguiprnent (Stowe, White)
Several specialized laboratory,equipment items have been
designed and constructed during the'quarter. (a) A small bench-
top extruder has been assembled andiis being used to make bonded
granular rods for TC-type devices. (b) Aerosol filling equipment
is now operational and small individualized aerosol containers
have been prepared to test experimental tobacco extracts.
(c) A 10-port smoking machine using''a single piston and incorporating
very low dead volume was specially'developed for filtration research
by Dr. Harris. Puff profiles and tar delivery are very reproducible,
but TPM moisture is 1 .5-2.0 m/cigt~ lower than values obtained from
the Phipps and Bird machine. ~d) Assembly of a small electrostatic
precipitator suitable for generatin~ pure smoke vapor phase for
taste testing is underway. Work wi l continue as time permits.
III. Gas Phase Filtration (Reynolds, Wheeler)
With the exception of the evaluation of carbon fibers, research on gas
phase filtration was terminated on March 31, 1973. Final reports are
complete (RDM's, 1973, No. 10, No. 12, and No. 14).
Eight samples of carbon fiber materials from the Carborundum Company
were received in April, and three of these have been made into filters for
snoke analysis. Results indicate no significant advantage in gas phase
removal characteristics. Handling of the carbon fiber materials has proven
a problem due to excessive dusting of the material. . For this reason work on
the remaining samples has been suspended. Work will only be continued on samples
that do not present a hazard. A status letter to the Carborundum Company has
been prepared.
TOBACCO EXTENDER (White)
Preliminary evaluation is nearly complete of a possible new extender for
tobacco. Blends of ordinary popcorn with tobacco at levels of 12.5, 25, and 50%
popcorn by volume have been examined (CIM, 1973, No. 4). Ground popcorn has a
very low density and high filling capacity and when mixed with tobacco does
not affect the burning characteristics of the'cigarette. Taste tests by Research
Personnel indicate a bland tasting smoke with no serious off-taste. At lower
levels (12.5' and less) there is no detectable difference in mainstream smoke.
:.ide-stream smoke is detectably different, especially' at higher levels.
Preliminary smoke data, based on standard vapor phase analyses and vapor
phase profile determination, indicate no new combustion products. No serious
-nufacturing problems are apparent as popcorn could be rolled, cut and possibly
re-expanded. Potential economics look favorable as usage at the 25% level
by volume (11o by weight) would reduce the cost of a cigarette by 37%.
A patent search has been requested.
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,-i?vICE TO ENGINEERING - AIR POLLUTION CONTROL (Project 1904, Wheeler)
Microscopic counting and sizing determinations were made on ten asbestos
samples.
~ MISCELLANEOUS SERVICE
I. Service to Archer (Project 4900, Wheeler)
Microscopic sizing and counting determinations were made on four asbestos
sarnpl es.
II. Service to Manufacturing (Harris)
Assistance and consultation were provided to Dr. Laurene regarding an
..;nusual problem with new Mark IX making equipment.
X ~4 - px~.&
Donald H. Piehl
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