SE438789B - FILTER MATERIAL FOR CLEANING GAS MEDICAL FROM AT LEAST ONE PRESENT SPECIFIED SUBSTANCE, TOBACCO SMOKING FILTER AND USE OF THE FILTER MATERIAL - Google Patents
FILTER MATERIAL FOR CLEANING GAS MEDICAL FROM AT LEAST ONE PRESENT SPECIFIED SUBSTANCE, TOBACCO SMOKING FILTER AND USE OF THE FILTER MATERIALInfo
- Publication number
- SE438789B SE438789B SE7909923A SE7909923A SE438789B SE 438789 B SE438789 B SE 438789B SE 7909923 A SE7909923 A SE 7909923A SE 7909923 A SE7909923 A SE 7909923A SE 438789 B SE438789 B SE 438789B
- Authority
- SE
- Sweden
- Prior art keywords
- filter material
- material according
- filter
- substance
- layer
- Prior art date
Links
- 239000000463 material Substances 0.000 title claims description 41
- 239000000126 substance Substances 0.000 title claims description 16
- 241000208125 Nicotiana Species 0.000 title claims 3
- 235000002637 Nicotiana tabacum Nutrition 0.000 title claims 3
- 238000004140 cleaning Methods 0.000 title 1
- 230000000391 smoking effect Effects 0.000 title 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 14
- 239000002245 particle Substances 0.000 claims description 9
- 239000008187 granular material Substances 0.000 claims description 8
- 229910052751 metal Inorganic materials 0.000 claims description 7
- 239000002184 metal Substances 0.000 claims description 7
- 229920002301 cellulose acetate Polymers 0.000 claims description 6
- 239000011368 organic material Substances 0.000 claims description 6
- 239000011148 porous material Substances 0.000 claims description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 5
- 229920002678 cellulose Polymers 0.000 claims description 4
- 239000001913 cellulose Substances 0.000 claims description 4
- 229910052802 copper Inorganic materials 0.000 claims description 4
- 239000010949 copper Substances 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 150000001875 compounds Chemical class 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
- 239000000779 smoke Substances 0.000 claims description 3
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 2
- 229920002307 Dextran Polymers 0.000 claims description 2
- 229920001202 Inulin Polymers 0.000 claims description 2
- 229920002472 Starch Polymers 0.000 claims description 2
- 230000004913 activation Effects 0.000 claims description 2
- 229910052793 cadmium Inorganic materials 0.000 claims description 2
- BDOSMKKIYDKNTQ-UHFFFAOYSA-N cadmium atom Chemical compound [Cd] BDOSMKKIYDKNTQ-UHFFFAOYSA-N 0.000 claims description 2
- 229910052791 calcium Inorganic materials 0.000 claims description 2
- 239000011575 calcium Substances 0.000 claims description 2
- 229940043430 calcium compound Drugs 0.000 claims description 2
- 150000001674 calcium compounds Chemical class 0.000 claims description 2
- 159000000007 calcium salts Chemical class 0.000 claims description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 claims description 2
- 239000010419 fine particle Substances 0.000 claims description 2
- JYJIGFIDKWBXDU-MNNPPOADSA-N inulin Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)OC[C@]1(OC[C@]2(OC[C@]3(OC[C@]4(OC[C@]5(OC[C@]6(OC[C@]7(OC[C@]8(OC[C@]9(OC[C@]%10(OC[C@]%11(OC[C@]%12(OC[C@]%13(OC[C@]%14(OC[C@]%15(OC[C@]%16(OC[C@]%17(OC[C@]%18(OC[C@]%19(OC[C@]%20(OC[C@]%21(OC[C@]%22(OC[C@]%23(OC[C@]%24(OC[C@]%25(OC[C@]%26(OC[C@]%27(OC[C@]%28(OC[C@]%29(OC[C@]%30(OC[C@]%31(OC[C@]%32(OC[C@]%33(OC[C@]%34(OC[C@]%35(OC[C@]%36(O[C@@H]%37[C@@H]([C@@H](O)[C@H](O)[C@@H](CO)O%37)O)[C@H]([C@H](O)[C@@H](CO)O%36)O)[C@H]([C@H](O)[C@@H](CO)O%35)O)[C@H]([C@H](O)[C@@H](CO)O%34)O)[C@H]([C@H](O)[C@@H](CO)O%33)O)[C@H]([C@H](O)[C@@H](CO)O%32)O)[C@H]([C@H](O)[C@@H](CO)O%31)O)[C@H]([C@H](O)[C@@H](CO)O%30)O)[C@H]([C@H](O)[C@@H](CO)O%29)O)[C@H]([C@H](O)[C@@H](CO)O%28)O)[C@H]([C@H](O)[C@@H](CO)O%27)O)[C@H]([C@H](O)[C@@H](CO)O%26)O)[C@H]([C@H](O)[C@@H](CO)O%25)O)[C@H]([C@H](O)[C@@H](CO)O%24)O)[C@H]([C@H](O)[C@@H](CO)O%23)O)[C@H]([C@H](O)[C@@H](CO)O%22)O)[C@H]([C@H](O)[C@@H](CO)O%21)O)[C@H]([C@H](O)[C@@H](CO)O%20)O)[C@H]([C@H](O)[C@@H](CO)O%19)O)[C@H]([C@H](O)[C@@H](CO)O%18)O)[C@H]([C@H](O)[C@@H](CO)O%17)O)[C@H]([C@H](O)[C@@H](CO)O%16)O)[C@H]([C@H](O)[C@@H](CO)O%15)O)[C@H]([C@H](O)[C@@H](CO)O%14)O)[C@H]([C@H](O)[C@@H](CO)O%13)O)[C@H]([C@H](O)[C@@H](CO)O%12)O)[C@H]([C@H](O)[C@@H](CO)O%11)O)[C@H]([C@H](O)[C@@H](CO)O%10)O)[C@H]([C@H](O)[C@@H](CO)O9)O)[C@H]([C@H](O)[C@@H](CO)O8)O)[C@H]([C@H](O)[C@@H](CO)O7)O)[C@H]([C@H](O)[C@@H](CO)O6)O)[C@H]([C@H](O)[C@@H](CO)O5)O)[C@H]([C@H](O)[C@@H](CO)O4)O)[C@H]([C@H](O)[C@@H](CO)O3)O)[C@H]([C@H](O)[C@@H](CO)O2)O)[C@@H](O)[C@H](O)[C@@H](CO)O1 JYJIGFIDKWBXDU-MNNPPOADSA-N 0.000 claims description 2
- 229940029339 inulin Drugs 0.000 claims description 2
- 229910052749 magnesium Inorganic materials 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 229920001282 polysaccharide Polymers 0.000 claims description 2
- 238000000197 pyrolysis Methods 0.000 claims description 2
- 235000019698 starch Nutrition 0.000 claims description 2
- 239000008107 starch Substances 0.000 claims description 2
- 229910052723 transition metal Inorganic materials 0.000 claims description 2
- 150000003624 transition metals Chemical class 0.000 claims description 2
- 239000013543 active substance Substances 0.000 description 3
- 150000002736 metal compounds Chemical class 0.000 description 3
- 239000012876 carrier material Substances 0.000 description 2
- 235000019504 cigarettes Nutrition 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 125000000129 anionic group Chemical group 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
- A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
- A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
- A24D3/06—Use of materials for tobacco smoke filters
- A24D3/16—Use of materials for tobacco smoke filters of inorganic materials
-
- A—HUMAN NECESSITIES
- A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
- A24D—CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES FOR CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES
- A24D3/00—Tobacco smoke filters, e.g. filter-tips, filtering inserts; Filters specially adapted for simulated smoking devices; Mouthpieces for cigars or cigarettes
- A24D3/06—Use of materials for tobacco smoke filters
- A24D3/08—Use of materials for tobacco smoke filters of organic materials as carrier or major constituent
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Inorganic Chemistry (AREA)
- Cigarettes, Filters, And Manufacturing Of Filters (AREA)
- Filtering Materials (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Description
7909923-0 storleksordningen 0,04 sek. Den filtret nâende cigarrett- rökens temperatur ökar under glödens närmande till filtret från ungefärligen rumstemperatur till 75 - 90°C. 7909923-0 on the order of 0.04 sec. The temperature of the filter reaching the cigarette smoke increases as the embers approach the filter from approximately room temperature to 75 - 90 ° C.
Hittills har man använt flera olika substanser och flera konstruktioner som filtermaterial för gasformiga medier. En stor del av dessa filtermaterial har haft som aktiva medel olika organiska substanser, oorganiska salter och dessa fun- gerat som sådana som filtermaterial eller de har varit på olika sätt bundna till bärarmaterial. Som bärarmaterial har man använt framförallt aktivt kol, olika fibertyper, cellulosa, cellulosaderivater osv. Inget av dessa tidigare beskrivna filtermaterial har visat sig vara riktigt adekvat, framförallt då man kräver stor effektivitet under en kort filtreringsperiod och under begränsade volymförhållanden vad gäller filtermaterialets omfång. Detta gäller speciellt vid en sådan filtreringsprocess som förekommer t.ex. vid cigarrettfilter. En annan nackdel med dagens filtermate- rial är att dessa är för dyra t.ex. för engângsändamâl.So far, several different substances and several constructions have been used as filter materials for gaseous media. A large part of these filter materials have had as active agents various organic substances, inorganic salts and these have functioned as such as filter materials or they have been in various ways bound to carrier materials. The carrier material used is mainly activated carbon, various types of fiber, cellulose, cellulose derivatives, etc. None of these previously described filter materials have proved to be really adequate, especially since great efficiency is required during a short filtration period and under limited volume conditions in terms of the scope of the filter material. This is especially true in such a filtration process that occurs e.g. at cigarette filters. Another disadvantage of today's filter materials is that these are too expensive, e.g. for one-time purposes.
Enligt föreliggande uppfinning har det överraskande visat sig att man har lyckats undanröja ovan beskrivna och andra nackdelar och man har fått fram ett effektivt, industriellt lätt framställbart, relativt billigt filtermaterial.According to the present invention, it has surprisingly been found that the above-described and other disadvantages have been eliminated and an efficient, industrially easily manufacturable, relatively inexpensive filter material has been obtained.
Filtermaterialet enligt uppfinningen, vilket är av det inledningsvis angivna slaget, kännetecknas av att det tvär- bundna polymera materialet är en tvärbunden polyhexos eller ett tvärbundet polyhexosderivat.The filter material according to the invention, which is of the type indicated at the outset, is characterized in that the crosslinked polymeric material is a crosslinked polyhexose or a crosslinked polyhexose derivative.
Som aktivt ämne med förmåga att avlägsna vissa substan- ser ur de gasformiga medierna användes t.ex. aktiva metall- föreningar, varvid metallens mängd i förhållande till mäng- den grundsubstans (skelettsubstans) kan reproducerbart av- passas till ett optimalt värde, nämligen inom omrâdet 2 - 50 vikt-%, företrädesvis 5 - 35 vikt-%, samtidigt som metall- föreningarna är synnerligen jämnt fördelade inom filtermate- rialet.As an active substance capable of removing certain substances from the gaseous media, e.g. active metal compounds, wherein the amount of the metal in relation to the amount of the basic substance (skeletal substance) can be reproducibly adjusted to an optimum value, namely in the range 2 - 50% by weight, preferably 5 - 35% by weight, while metal the compounds are extremely evenly distributed within the filter material.
De aktiva metallföreningarna kan vara kemiskt bundna till anjoniska grupper i skelettmaterialet och/eller vara fritt inneslutna i skelettmaterialets hâlrum. 7909925-0 Filtermaterialet enligt uppfinningen kan, med eller utan metallföreningar, också innefatta aktiva kemiska organiska föreningar.The active metal compounds may be chemically bonded to anionic groups in the skeletal material and / or be freely entrapped in the cavities of the skeletal material. The filter material of the invention may, with or without metal compounds, also comprise active chemical organic compounds.
Skelettsubstansens porstorlek kan på förhand regleras och bestämmas med hänsynstagande till dess användning.The pore size of the skeletal substance can be regulated in advance and determined taking into account its use.
Filtermaterialet enligt uppfinningen har porer som väsentli- gen sträcker sig från yta till yta utan att bilda uppslutna fickor, blindtarmar, som hindrar gasgenomsläppligheten.The filter material according to the invention has pores which substantially extend from surface to surface without forming trapped pockets, appendixes, which impede gas permeability.
Filtermaterialet enligt uppfinningen har vidare en stor aktiv yta, vilken kan regleras genom porstorlek och tvärbind- ningsgrad respektive filtermaterialets s.k. partikelstorlek i torr form samt i den miljö där det används.The filter material according to the invention further has a large active surface, which can be regulated by pore size and degree of crosslinking and the so-called filter material, respectively. particle size in dry form and in the environment in which it is used.
Genom att man kan variera de aktiva substansernas kon- centration och egenskap genom val av lämpliga substanser kan filtermaterialet fås i hydrofob och/eller hydrofil form.By being able to vary the concentration and property of the active substances by selecting suitable substances, the filter material can be obtained in hydrophobic and / or hydrophilic form.
Polyhexosen eller polyhexosderivatet i filtermaterialet enligt uppfinningen kan bestå av eller härröra från en natur- ligt förekommande eller syntetisk kolhydratpolymer, såsom cellulosa, stärkelse eller inulin respektive dextran eller blandningar därav.The polyhexose or polyhexose derivative in the filter material of the invention may consist of or be derived from a naturally occurring or synthetic carbohydrate polymer, such as cellulose, starch or inulin or dextran or mixtures thereof.
De för filtermaterialet enligt uppfinningen ifrågakom- mande metallerna utgöres utöver en metall ur gruppen Ca, Mg, Ba, Al och Cu i första hand av övergångsmetallerna Ti, V, Cr, Mn, Fe, Co, Ni, Mo och Pd, varvid metallerna väljes med utgångspunkt från de i varje filtreringsprocess speciellt önskade selektiva effekterna.The metals in question for the filter material according to the invention, in addition to a metal from the group Ca, Mg, Ba, Al and Cu, consist primarily of the transition metals Ti, V, Cr, Mn, Fe, Co, Ni, Mo and Pd, the metals being selected based on the selective effects specifically desired in each filtration process.
Sålunda användes för rening av gasformiga medier från kadmiumhaltiga föreningar företrädesvis en kalciumförening, lämpligen ett fritt oorganiskt kalciumsalt och för rening av gasformiga medier från kolmonoxid företrädesvis järn och/ eller koppar i oxiderad form.Thus, for the purification of gaseous media from cadmium-containing compounds, a calcium compound, preferably a free inorganic calcium salt, is preferably used, and for the purification of gaseous media from carbon monoxide, preferably iron and / or copper in oxidized form.
Enligt en utföringsform av uppfinningen föreligger fil- termaterialet i form av granula, vilka är belagda med ett semipermeabelt skikt av organiskt material, exempelvis ett skikt av cellulosaacetat.According to an embodiment of the invention, the filter material is in the form of granules, which are coated with a semipermeable layer of organic material, for example a layer of cellulose acetate.
Med speciell fördel kan filtermaterialet ha formen av fina partiklar eller granuler, exempelvis kulor eller cylind- rar med en tvärdimension av 0,005 - 3 mm, varigenom framställ- 7909925-0 ningen av ett av filtermaterialet bestående eller filter- materialet innehållande filter med på förhand bestämbart genomströmningsmotstånd etc. underlättas.With special advantage, the filter material can be in the form of fine particles or granules, for example spheres or cylinders with a transverse dimension of 0.005 - 3 mm, whereby the production of a filter consisting of the filter material or the filter material containing with predeterminable flow resistance etc. is facilitated.
Filtermaterialet enligt uppfinningen kan föreligga i blandning med partiklar eller granuler av ett med eterartade bindningar tvärbundet polymert, poröst material, vilka par- tiklar eller granuler lämpligen är belagda med ett semiper- meabelt skikt av organiskt material, exempelvis ett skikt cellulosaacetat. Det kan även föreligga i blandning med partiklar av aktivt kol, lämpligen aktivt kol erhållet genom pyrolys och aktivering av material enligt uppfinningen.The filter material according to the invention may be in admixture with particles or granules of a polymeric, porous material crosslinked with ethereal bonds, which particles or granules are suitably coated with a semipermeable layer of organic material, for example a layer of cellulose acetate. It may also be present in admixture with particles of activated carbon, suitably activated carbon obtained by pyrolysis and activation of materials according to the invention.
Partiklarna av aktivt kol kan vara belagda med ett semi- permeabelt skikt av organiskt material, exempelvis ett skikt av cellulosaacetat.The activated carbon particles may be coated with a semi-permeable layer of organic material, for example a layer of cellulose acetate.
Claims (12)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI783678A FI67666C (en) | 1978-11-30 | 1978-11-30 | FILTER MATERIAL |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| SE7909923L SE7909923L (en) | 1980-05-31 |
| SE438789B true SE438789B (en) | 1985-05-13 |
Family
ID=8512195
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| SE7909923A SE438789B (en) | 1978-11-30 | 1979-11-30 | FILTER MATERIAL FOR CLEANING GAS MEDICAL FROM AT LEAST ONE PRESENT SPECIFIED SUBSTANCE, TOBACCO SMOKING FILTER AND USE OF THE FILTER MATERIAL |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS55141186A (en) |
| BE (1) | BE880324A (en) |
| DK (1) | DK505179A (en) |
| FI (1) | FI67666C (en) |
| SE (1) | SE438789B (en) |
| ZA (1) | ZA796493B (en) |
-
1978
- 1978-11-30 FI FI783678A patent/FI67666C/en not_active IP Right Cessation
-
1979
- 1979-11-28 DK DK505179A patent/DK505179A/en not_active Application Discontinuation
- 1979-11-29 BE BE0/198339A patent/BE880324A/en not_active IP Right Cessation
- 1979-11-29 ZA ZA00796493A patent/ZA796493B/en unknown
- 1979-11-30 JP JP15447279A patent/JPS55141186A/en active Pending
- 1979-11-30 SE SE7909923A patent/SE438789B/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55141186A (en) | 1980-11-04 |
| SE7909923L (en) | 1980-05-31 |
| FI67666B (en) | 1985-01-31 |
| DK505179A (en) | 1980-05-31 |
| FI783678A (en) | 1980-05-31 |
| ZA796493B (en) | 1980-12-31 |
| FI67666C (en) | 1985-05-10 |
| BE880324A (en) | 1980-05-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3169171B1 (en) | Electronic vapour provision system | |
| JP4224457B2 (en) | Smoking filter | |
| US6591839B2 (en) | Filter material for reducing harmful substances in tobacco smoke | |
| US4188418A (en) | Separation process | |
| JPS5953085B2 (en) | Filter media and their manufacturing method | |
| JP2016019980A (en) | Active carbon and water purifier using the same | |
| US4018678A (en) | Method of and apparatus for fluid filtration and the like with the aid of chitosan | |
| WO2013011312A1 (en) | Porous carbon and methods of production thereof | |
| EP0000625A1 (en) | Tobacco smoke filter element with alkali ferrate supported on granular material | |
| JP2009538723A (en) | Nonwoven media incorporating ultrafine or nano-sized powder | |
| JP2006520270A (en) | Filter media with improved ability to inhibit microorganisms | |
| NL7908701A (en) | FILTER MATERIAL, PARTICULARLY FOR CIGARETTE FILTER. | |
| CN104720104A (en) | Filter tip addition agent for selectively reducing crotonaldehyde in smoke of cigarette and preparing method and application thereof | |
| US2815761A (en) | Fibrous tobacco smoke filter | |
| US3032445A (en) | Tobacco smoke filters | |
| DK152247B (en) | tobacco smoke | |
| SE438789B (en) | FILTER MATERIAL FOR CLEANING GAS MEDICAL FROM AT LEAST ONE PRESENT SPECIFIED SUBSTANCE, TOBACCO SMOKING FILTER AND USE OF THE FILTER MATERIAL | |
| JPH06104200B2 (en) | Adsorption sheet manufacturing method | |
| US3349779A (en) | Cigarette filter element containing certain hexahydrotriazines for the selective removal of acrolein | |
| KR20200053773A (en) | Process for producing antibacterial activated carbon and antibacterial activated carbon filter using the same | |
| JP3792672B2 (en) | Aldehyde gas decomposition removing material and method for producing the same | |
| JP5635782B2 (en) | Granular composition carrying chitosan and cigarette filter containing the same | |
| JP7301591B2 (en) | Manufacturing method for residual chlorine removal filter body | |
| US3359990A (en) | Cigarette filter element containing water-soluble monomeric hydrazides for the selective removal of aldehyde vapors | |
| JP4378449B2 (en) | Adsorbent and production method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| NAL | Patent in force |
Ref document number: 7909923-0 Format of ref document f/p: F |
|
| NUG | Patent has lapsed |
Ref document number: 7909923-0 Format of ref document f/p: F |