Dr. C.Z. Greig/JJ 13 th May, 1983. ST. M=--,= Closely following the launch of Barclay by BAT Benelux, Ed. L---=ens launched St. Moritz into the Belgian/Dutch markets. The launc~~ publicity encompassed similar "aerodynamic" claims to those used by Baz=lay, based on the use of a grooved filter. A law suit between Laure=s and BAT ensued, with Philip Morris, although not officially objec-_:~ng, apparently siding with Laurens. GR&DC was requested, as a matter of urgency, to assist RAT Benel= in performing routine brand analyses and to make some special obser-.-azions and measurements. This note is a summary of the work done in G? ~- to assist BAT Benelux. It is split into a number of sections, in wti=h the reasons for the work and the results, together with any impliza-1:1ons, are described. 1. ~~cutlne brand analvsis While t-here have been and continue to be a number of suggestions for mcKiification of filter holders to attempt to minic alleged human blocki=a behaviour, the more immediate requirement for BAT Beielux was for a _--outine brand analysis performed under standard conditions. This was -4- order to corroborate BAT Benelux's own laboratory results and to act a-sa a neutral referee since Laurens had purported that analyses car-_L-_-d out by TNO, the Dutch national testing laboratory, showed rout:L=e figures greater than the 1mg of tar claimed on the pack. L4 i-z,~ -e.: Whils': TNO as an institution is held in high scientific regard, they are by nc =eans as experienced in cigarette smoking analyses as BAT Benelux and MFIDC, and it was susnected that Laurens were using TNO as a "red 1 i e Routine brand analyses of St. Moritz and Barclay in GR&DC gave -e data in Table 1. (attached) . These results confirm the fact that the pack labelling of Barc---v as "less than 1mg" or "Img" tar is accurate- The smoke data was se=t to BAT Benelux on 4th April, 1982. Comments on St. Moritz are:- No expanded tobacco content (hexane flotation). No menthol, though St. Moritz is normally regarded as a Uli menthol brand world wide. CD -_i) Use of the Filtrona Astra filter - see later section. CD ~zv) Low blend nicotine (half that of Barclay) . -0 Higher blend sugars (more flue-cured?) . C:) Construction otherwise conventional at this deliverv in the target markets. BATCo document for Province of British Columbia 4 November 1999 Filter With the claim for "aerodynamics" made for St. Moritz, it as obvir--.:s that an unusual filter construction was involved. Examination in RA:: Benelux showed this to be of the "Astra" type marketed by Filtrona. There have been a number of prior designations of "Astra" and there are a: n,---er of recent variants, but the filter an St. Moritz is essentially the --asic" Astra. In this, 22 or 23 circumferentially disposed grooves axiall to the filter without twist are prepared from an outer corrugated mater!---l 1--inated to the inner plugwrap surrounding the filter material. A dia----am and description of this filter are shown in Appendix 1. As used = St. Moritz, the filter plug is 25mm. long composed of two CA secti=s, the tobacco end of 10mm and the mouth of 15mm. No real difference in pressure drop per unit length could be found when the indiv~.dual plugs were separated and measured bound. This dual filter cons=-_ction, without differences in pressure drop per unit length of the -4-4vidual elements, is unusual and suggests that the construction is ad=-zed more from aesthetic aspects than with a real filt-rational desi= intent (i.e. Bul I eye avoidance?) The porosity of the inner plugwrap is circa 25CU, and that of the =----ucated portion circa 250CU, though the latter is difficult to meas--=e accurately. An anchor line of circa 2mm width an the inner pluc-.;---an is used to secure the two plugs. The corrugated assembly is attached to the cigarette using 29 = ::--'Puing perforated with 4 row laser pre-perforation in a zone 11 - 15mm from --'-e mouth end. The gluing regime is overall glued in t-he mouth end t-- ventilation zone area, and for the anchorage to the tobacco rod. The azea under the ventilation zone extending to the rod anchorage is ungl---A-. The reason for this will be obvious from the section on block.:~rg (q. v) . BlockLnq experiments The objections to grooved filters are predominantly that smokers are liable to block or severely obstruct several or all of the grooves by their lips during the puff. There is also the more general ques,clon of the alleged practice of ventilation zone blocking by the smoker's fingers. C) OD N-) BATCo document for Province of British Columbia 4 November 1999 Thus, in the case of a ventilated grooved filter cigarette there are two separate possible means of filter ventilation obstruction. In the case of Barclay, it is often contended that the rigidity of the tipp:Lng above the grooves is insufficient to prevent a smoker's lips W-L flattening the tipping into the groove, thus blocking it partly or completely. This action defeats the ventilation mechanism and is CA' purported to lead to higher smoke deliveries. To counter these allegations, Barclay is now normally manufactured using a higher strength tipping to minimise potential collapse. This change has not however countered objections that collapse is probable, and indeed modifications to cigarette holders (discs, washers) for routine smoking have been mooted. In the case of St. Moritz, the construction involving 20 + grooves rather than four, and the relatively rigid nature of the corrugated constm-action suggests that inadvertent blocking would be difficult round the complete periphery. This does not of course mean that certain dia.r---t--ically opposed areas could not be blocked by the lips, nor that the smokers' fingers could intercept the ventilation holes. However, the presence of grooves or flutes leading from the vent~ilation zone to the tobacco rod, and protected from glue blockage in these relatively small grooves/flutes by the absence of a glued tipping paper, means that even when the tip or mouth end is blocked there is still a potential course for ventilating air flow. Now the ventilating air flow must occur against the normal flow i.e. toward the coal initially, but having reached the tobacco end of the filter it may then turn thrcuch 180o and enter the filter as normal. The porosity of the com= ned corrugated material and inner plugwrap is small (= equivalent to 3% ventilation) so although a minute amount of ventilating air will traverse the plugwrap/corrugated composite the main flow will be counter to the normal direction until it turns back. Incidentially, it is thought that the provision of the small but finite composite permeability is intended to circumvent the B&W patents which specify a totally impervious plugwrap. Measurements were made initially of the ventilation at various durations at puff volumes of 35 and 50ml-s. The method used is not eauivalent to the normal ventilation tester and gives results lower than U11 CD this instrument, which cannot be adapted for these investigations. The CD results here are systematically lower than that of a standard ventilation -Ii C) CC) BATCo document for Province of British Columbia 4 November 1999 - 4 - ventilation tester but are internally consistent. While the ventilation by Standard tester was 73% on the test cigarette, the result at 35m?-S/2secs found was 63%. Extension to 50mZs/2secs showed 63% again and the extremes, at either 35 or 50mts and 1.16secs duration, were 61%. The conclusion is thus that there is little if any effect of flowrate on ventilation under the experimentally available conditions. The effect of blocking ventilation holes in the tipping. Sequentially, small patches of impervious tape covering 1/4 of the c-4-cumference were attached, to mimic sealing by one finger, both fingers and then more general abuse. 1/4 sealed 1/2 sealed (diametrically opposed) 3/4 sealed All sealed Ventilation % 57 55 32 0 The effect of tip groove blocking Sequentially, as above, 1/4 of the grooves were sealed with Snopake typewriter erasing material. Ventilation % 1/4 sealed 55 1/2 sealed (diametrically opposed) 50 All sealed 40 Combination of groove and ventilation blocking Ventilation % Tip 1/2 sealed and vent holes 1/2 sealed diametrically opposed 40 All tip sealed, 1/4 vent holes sealed 35 All tip sealed 1/2 vents sealed, diametrically opposed 29 All tip sealed 3/4 vents sealed 19 C:) C) C) co BATCo document for Province of British Columbia 4 November 1999 These data are easier to assimilate in a diagrammatic form here or ;Ln Avoendix 2. 0 ~-'4 denotes vent hold blocking jIM denotes groove/flute blocking. Unblocked normal 62% 0 Grooves/flutes 1/4 55% (7) Vent holes 1/4 Grooves/flutes 1/2 57% 50% C) Vent holes 1/2 Grooves/flutes all 55% 40% 0 Vent holes 3/4 Grooves/flutes 1/2 32% Vent holes 1/2 40% 0 0 Grooves all Vent holes 1/4 35% 0 Grooves all Vent holes 1/2 29% Possibly-the most severe human situation. Grooves all Vent holes 3/4 19% (J.4 0 CD CD C) CO (-n BATCo document for Province of BritiSh Columbia 4 November 1999 - 6 - The conclusions from these blocking experiments bear out the premise that "reverse flow" should occur when all the grooves/flutes are blocked. The ventilation hole total blocking is not a realistic possibility since, even if finger blocking does take place it is rather unlikely to be more than ~ of the periphery. Blocking of the grooves/flutes, ds alleged to take place in Barclay human smoking, only gives a minor increase in delivery even if ~ of the grooves are blocked. Full blocking is unlikely, but the most probable "worst case" could be groove/flute blocking plus ~ ventilation hole finger blocking. "If this is so, ventilation drops to approximately two thirds of the initial value. Delivery in this case can be calculated to be about 5mg tar. These data sent to RAT Benelux 25th March 1983 and B&W 3rd April, 1983. Exneriments have been conducted outside this examination with complete groove blocking of Barclay and complete groove/flute blocking for St. Mc=-4tz, and gave the following data at standard smoking conditions. TPM Nic Water Tar CO % CO mg Puff No. Barclay (U.S.) standard 1.54 0.11 0.19 1.24 0.26 0.95 8.9 Grooves blocked 15.53 1.24 1.68 12.61 4.06 11.36 7.0 St. Moritz standard 3.37 0.20 0.24 2.93 0.51 2.28 11.0 Grooves/flutes blocked 8.85 0.55 0.59 7.71 1.62 6.11 9.3 -he data should not be closely compared with earlier routine brand analysis data due to limited ports used in the above. Nevertheless, the conclusion must be that as summarised above, the "reserve" ventilation system of St. Moritz can ensure a considerably lower "blocked" delivery than'Barclay. Particle size distribution A characteristic of "aerodynamic" filters in which air and smoke are mixed in "shear zones" is an increased particle size of the smoke aerosol. No explanation of this is as yet available. An examination of Cambridge (US) , Barclay and St. Moritz (both Bene lux/Sol land) was conducted at the request of B&W using a newly developed laser particle size distribution system. This system is still under development C) 00 O\ BATCo document for Province of BritiSh Columbia 4 November 1999 - 7 - and is as yet not fully calibrated, so that the values are not absolute. Examination of Cambridge showed a mean particle size of 0. 184 (micron), with Barclay at 0.27g and St. Moritz at 0.24p. Assuming that the Cambridge value is "standard" for a non-turbulent filter system, and Barclay is "standard" for the fully turbulent system, then St Moritz can be regarded as about 2/3 of the way toward Barclay i.e. there is a c6 nsiderable degree of particle growth, which may be interpreted as indicating turbulence (see also the section on flow visualisation) . Subjective assessment A limited, three person assessment of Barclay and St Moritz was conducted in Product Development at GR&DC. A common element in assessment of Barclay was the considerable mouthful of smoke and very high impact. The Barclay blend/type was assessed as essentially US Blend/Type, possible with some greater amount of air cured character. St Moritz was, by comparison, a much blander smoke, with much lower mouth sensations and very pronouncedly less impact. The blend type was felt to be more "European", with Oriental notes. It was felt that Barclay had a considerable degree of "presence" and was generally much more rewarding to the smoker. St Moritz was a typical low delivery cigarette with little reward. Flow visualisation In order to assess "aerodynamic" claims, various "glass mouths" have been manufactured. At GR&DC this is a cylinder of 5cm diameter and 12cm long and a volume of 235mZs, from which a 35mZ puff of 2 secs. duration is taken by a single port engine. Visual examination of Cambridge showed the typical thin, dense pencil-like plume of =oke emerging from the filter and diverging only slightly. Barclay showed the typical highly turbulent recirculating flow. St Moritz shows intermediate behaviour with some pencil-like streaming but also some turbulent mixing due to flow through the grooves. As the flow decreases in the last stages of the puff, it is possible to see streams of smoke exiting from individual grooves. These filament- like plumes are stable for some time. C) C) C:) co ___J BATCO document for Province of BritiSh Columbia 4 November 1999 - 8 - Video filming of these, together with various blockings of vent holes and grooves and flutes in a number of arrangements was conducted at the request of RAT Benelux and forwarded to them for Informatian and legal opinion on 31st March, 1983. Further wcrk Filtration efficiencies Work is in hand to determine the filtration efficiency of the core secti= of the Astra filter used on St Moritz to check Filtrana's handout da=a. Pluff by p=f-I deliveries Work is progressing on the measurement of puff by puff deliveries at puff vc-lumes of 35, 50 and 75mts. This data should indicate how human smo".