DE1079521B - Filter rod and filter elements consisting of it for tobacco smoke and manufacturing processes for this - Google Patents

Description

GERMAN

The invention relates to filter rods and filter elements made therefrom for tobacco smoke, in particular for cigarettes, and an associated manufacturing process; in particular, the invention relates to tobacco smoke filters made from continuous synthetic fibers a special additive that is firmly bound to the fiber surface.

A wide variety of filters have already been proposed been. The first consisted of crepe paper, cotton wool and similar masses of fibers. Through the Use of masses or wadding was apparently thought, the filtering effectiveness according to the disoriented Increase nature of the filter. However, such filters often showed a high pressure drop and are also for modern mass production is not well suited. In recent times one is therefore to use continuous parallel cellulose ester fibers for the production of filters. Such ongoing Fibers have the advantage that they work very well on today's high-speed filter making machines let process.

Attempts have also been made to improve filters made from such fibers by using additives. It has been suggested to add certain types of additives to the fibers or the filters thereby apply that on the fibers z. B. generates an electrostatic charge and the charge to attract the additives and to bind to the fibers. Various other procedures as well and devices for applying the additives are known. With all these known filters However, the additives are usually not bound very tightly to the fibers, but the additives tend to dust out of the filters, which of course is extremely undesirable. Also require the familiar Process for applying additives in many cases dusting chambers or other special equipment, which increases the cost of filter production. Pollination chambers must also because of the risk of dust explosions with an explosion valve or lid and other safety precautions are provided, etc. There is accordingly a great need for filter material with firmly adhering Additive and an improved process for its production.

It has now been proposed a filter element of the type in question, in which the Fibers or threads fused by a solvent (e.g. a plasticizer) and / or by heat as well as an associated manufacturing process. Furthermore, it has also already been suggested that the tackifying Effect of the means used under the aforementioned proposal other than welding the fibers also to hold the pül-filter rod and from it

Filter elements for tobacco smoke
and manufacturing process for this

Applicant:

Eastman Kodak Company,
Rochester, NY (V. St. A.)

Representative: Dr.-Ing. W. Wolff, patent attorney,
Stuttgart-N, Lange Str. 51

Claimed priority:
V. St. v. America 9 December 1957

George Patrick T ^ uey
and Robert Chester Mupipower II,

Kingsport, Tenn. (V. Is. A.),
have been named as inventors

take advantage of deformed additives. A binder can also be added to the plasticizer are soluble in the plasticizer with advantage at elevated temperature, but in any case at room temperature is insoluble, so that it does not penetrate into the fiber substance with the plasticizer, but remains on the fiber surface and contributes to the adhesion of the additive.

The object of the invention is now a filter rod and filter elements for tobacco smoke consisting of it with a content of an effective and particularly firmly adhering additive and a process in which such filters are produced in a simple manner and in which the additives are also proportionate large quantities - with the known processes usually no more than about 10 per cent material can be applied ■ - firmly adhering to the fibers can be applied. The additives should be applied to the fiber surface in finely divided form are and should give it a special roughness.

According to the invention, a filter corresponding to the object set is now realized in that 1 to 30, preferably more than 20 percent by weight of an additive is used which consists of at most 30, preferably 5 to 10 μ large, firm, generally in the form of knots and ribs on the Particles bound to the fiber surface from an im

909- 769/180

Ranges from about 35 to 100 ° C melting higher molecular weight Solid consists of a waxy consistency. The aforementioned properties of the Additives allow it to initially be converted into a molten state (this melting is preferably made in combination with a suitable plasticizer), whereupon the melted Materials including the molten additive and plasticizer, the Incorporated fiber filter. When the melted (liquid) materials settle on the fibers, the Plasticizer absorbed by these. The normally solid material adheres to the when it cools down Surface of the fibers in the form of fine particles and forms knots and ribs or similar structures on the fiber surface. Such particles deposited in the form of knots and ribs are such as said, firmly bound to the fibers so that they will not loosen from the fibers when one of the undergoes normal treatment for the production of filters or during subsequent treatment and use the filter. The mechanical strength achieved goes so far that it is possible to use the additive to pack and handle containing filter rod in bales without the additive from loosens the fibers. This is also true when you have significant amounts of such particles on the fibers brings up. In other words, even if the fibers contain a significantly larger amount of additive than 10 percent by weight, based on the fibers, the particles do not crumble or dust out of the Filter off.

Fatty acid esters, fatty acids and fatty alcohols are preferably used as additives according to the invention in question. It is advantageous to use such additives with a certain, in connection with it plasticizers used are miscible in the molten state in all proportions, but in the plasticizers in question are essentially insoluble at room temperature.

High molecular weight fatty acid esters suitable as additives are, for. B. the esters of glycerol, des Ethylene glycol, propylene glycol, polyethylene glycol and polypropylene glycol with higher molecular acids suitable, which have melting points above 35 and below 100 ° C. Also the acetylated monoglycerides are within this melting point range. The following is a list of some of these connections compiled, which behave quite satisfactorily and those in plasticizers for cellulose acetate when heated, but soluble in the plasticizers are insoluble when the solutions are cooled to room temperature.

link

Glycerol monostearate

Diethylene glycol stearate

Ethylene glycol monostearate

Polyethylene glycol monostearate

Polyethylene glycol monostearate

Triglyceride of 12-oxystearic acid

(hydrogenated castor oil)

Acetylated monoglyceride from hydrogenated

Lard

Propylene glycol monostearate

57 to 61 54 to 59

57 to 60 50 to 60 54 to 57

84

42 to 44

58 to 62

The preferred compounds of this class are the monostearates of glycerol and propylene glycol, the acetylated monoglyceride and the hydrogenated castor oils, as these compounds for use are recommended in food and food containers.

The cellulose acetate plasticizers used as hot solvents for spraying the said esters can be used on the cellulose acetate strand are selected from those plasticizers which have been found suitable to convert the compressed strand into a solid or rigid filter rod tie. Suitable plasticizers are e.g. E.g .: glycerine di- and triacetate, glycerine di- and tripropionate, di- (methoxyethyl) - phthalate, ethyl phthalyl methyl glycolate, triethyl citrate and mixtures of these plasticizers. Glycerol triacetate or a mixture of glycerol diacetate and glycerol triacetate are preferred. These plasticizers are capable of making the cellulose acetate fibers into a solid rod without application to bind from heat.

ao To produce a sufficient amount of the higher molecular weight fatty acid ester on the surface of the fibers To obtain a strong and effective filter, the solid ester has been found to be useful in which plasticizer is dissolved in an amount of not less than 25% and not more than 80%. The preferred concentration of the dissolved higher molecular weight fatty acid ester in the plasticizer is 40 to 70%. The total amount of additive solution (plasticizer and dissolved ester) that is on the strand is sprayed depends on the type of continuous fibers (number and dimension of the fibers and the Degree of curl imparted to fibers) used and the ratio of plasticizer to the dissolved ester in the spray solution.

In order to obtain a sufficient amount of solid ester particles deposited on the fiber bundle, it is recommended to use 20 to 60% of a 50:50 mixture of plasticizers and glycerin (or glycol) esters to be applied to the fibers before they are transferred into a filter plug. This gives the fibers a solid additive content of 15 to 30%. In general it has been found that at least 10% the solid ester particles on the surface of the fibers must be distributed before a valuable Improvement of the filter efficiency can be achieved to the full extent.

The size of the solid ester particles that settle on the strand depends mainly on the the openings of the spray gun. It has been shown that particle sizes can be obtained from a conventional painter's spray gun easily maintained between 5 and 30 μ. With fine spray devices, however, you can spray obtained with particle sizes of 0.5 to 10 μ. As a general rule, it can be said that the use a spray arrangement with which a particle size of less than 20 μ is obtained is advisable. To this This leads to a filter that is easy to pull, because it is relatively large and deposited on the fibers Particulates tend to increase the pressure drop across the filter to a noticeable degree.

example 1

A strand of cellulose acetate yarn about 1.5 m long with 10,000 fibers of a single denier of 8 and an average crimp of 3.6 crimps per cm over the entire length is applied to one Spread out in width of about 30 cm. In this expanded state, the strand will be on both sides sprayed with a solution of equal weight

share glycerol monostearate and glycerol triacetate, taking a temperature inside the spray gun of 70 ° C is maintained. This solution is made by adding the solid glycerol monostearate to the liquid glycerol triacetate and heating the mixture to 60 to 70 ° C. As well as the glycerol monostearate melts, it dissolves in the glycerol triacetate, forming a homogeneous solution.

After the described treatment of the strand, it consists of 64% cellulose acetate fibers, 18% Glycerol monostearate and 18% glycerol triacetate (plasticizer) and is back into a compact Bundles or cords transferred and fed into a machine for producing cigarette filter plugs which he provided with a paper tube and cut into filter rods 90 mm long and 25.5 mm in circumference will. After storage for 20 minutes at 28 ° C, the rods are quite solid. Some of the bars are opened and observed under the microscope. It turns out that essentially all fibers have a rough, Have an irregular surface because the glycerol monostearate is a fine powder on the strand has settled, which is firmly bound to this by the plasticizer. Several rods are cut into filter tips 15 mm in length. These tips are placed on ten cigarettes (standard brand A) of 85 mm length, which are shortened by 15 mm to compensate for the length of the filter. These are ten filtered cigarettes on a smoke machine similar to that in Industrial and Engineering Chemistry, Vol. 28, pp. 836-839 (1936), essentially the same, smoked to stub lengths of 35 mm. The one through the cigarettes Spreading smoke is collected and analyzed for nicotine and tar content. The results are shown in Table 1.

Control filter without additives and control filter with a content of 18% glycerol triacetate (plasticizer) alone are crimped from the same Prepare strand as described above. These filters are used on the same cigarettes shortened by 15 mm of brand A. Ten of the cigarettes with the plasticizer-free filters and ten of the cigarettes With the filters containing 18% glycerol triacetate are also on the smoking machine smoked to stub lengths of 35 mm. The smoke that passes through the cigarettes is collected and analyzed for nicotine and tar content. The results appear in Table 1 as well.

Ten filterless "King-size" cigarettes (brand A) with a stub length of 35 mm are also smoked, which have not been shortened by 15 mm. The smoke that passes through the cigarettes is collected and analyzed for nicotine and tar content.

Table 1
Milligrams of nicotine and tar when smoking cigarettes with and without filters

Cigarettes without filter (85 mm total length)

Cigarettes
with acetate filters
(85 mm total length)

Cigarettes
with acetate filters
and a salary
of 18% glycerol triacetate
(85 mm total length)

Cigarettes
with acetate filters and a content of 18% glycerol triacetate and 18% glycerol monostearate (85 mm total length)

Average pressure drop in cm *)
Milligrams of tar from ten cigarettes
Milligrams of nicotine from ten cigarettes
Tar decrease due to the filter in%
Nicotine decrease as a result of the filter in%

170
29

9.0
150
25th
11.8
13.8

153
26th
10.0
10.4

9.8
110
20th
35.3
31.0

*) That means cm "water column at an air flow rate through the cigarette of 17.5 ml per second.

As can be seen from Table 1, the filter with the liquid plasticizer (binder) removes something less nicotine and tar than the no additive filter. But if the strand has that in the plasticizer dissolved glycerol monostearate is added, the effectiveness of the filter is significantly increased. The increase filter efficiency is achieved without a substantial increase in the pressure drop of the cigarette.

Example 2

55

A strand of cellulose acetate yarn about 1.5 m long containing 14,000 fibers and 15 denier per fiber with an average crimp level of 3.6 crimps per cm through the whole length is spread out analogously to Example 1 and with a solution of 70% hydrogenated castor oil and 30 weight percent glycerol triacetate sprayed (temperature of the solution inside the spray gun = 85 ° C). After this treatment, the strand consists of 70% cellulose acetate fibers, 21% hydrogenated castor oil and 9% glycerol triacetate and is treated and tested analogously to Example 1.

The analysis found only 102 mg of tar and 19 mg of nicotine in the smoke of ten cigarettes, the filter removes 40% more tar and 34.6% more nicotine than the replaced 15 mm long piece Tobacco filling. The average pressure drop of the filter cigarettes is 10.0 cm water column. Comparison filter with 10, 20 and 30% glycerol triacetate, the same crimped strand becomes similar Way made. The filters with a content of 10% plasticizer remove 20% more nicotine and 10% more tar; the filters with 20% plasticizer 18% more tar and 18% more nicotine; and the filters with 30% plasticizer 15% more tar and 17% more nicotine than the removed tobacco-filled ones Corresponds to a tip of 15 mm. The average pressure drop for the three sets of filter cigarettes ranges from 9.0 to 10.3 cm.

Example 3

A continuous strand of cellulose acetate made from 14,000 fibers of 5 denier per fiber and one average degree of curling of 3.6 per cm is only in a spray chamber when spread out with unheated glycerol triacetate plasticizer and then in another chamber with glycerine monostearate (melting point 57 to 61 ° C)

sprayed with the spray gun held at 85 ° C. When the liquid ester emerges from the Spray gun forms a mist of fine solid particles that spreads evenly over the surface of the strand distributed.

The strand treated in this way contains a combination of 67% cellulose acetate fibers, 17% glycerol monostearate and 16% glycerol triacetate plasticizer; it is further processed, tested and analogous to Example 1 analyzed. Only 99 mg of tar and 16 mg of nicotine are found in the smoke from ten cigarettes, which the filter removes so 42% more tar and 45% more nicotine than the replaced 55 mm long tobacco-filled tip. Of the average pressure drop of the filter cigarette is 10.3 cm.

As mentioned, higher molecular weight fatty acids are also suitable as an additive according to the invention. Man preferably uses those with melting points above 35 and below 100 ° C, the gross formulas

C _n H _2n O ₂ and C "H ₂ " _ _2X O ₂

correspond, where η is a number between 10 and 24 and χ is a number up to 5. The first formula represents saturated fat and the second unsaturated one. Some of these compounds are listed in the tables below, which are particularly useful because they are soluble in the plasticizers serving as binders for the cellulose acetate when heated, but insoluble in the plasticizers when the solutions are cooled.

Surname Saturated fatty acids (C _n H _2n O ₂ ) Fp- ( ⁰ Q 43 to 44
53 to 54
62 to 63
68 to 70 Lauric acid Mvristic acid ... Palmitic acid ... Stearic acid .... formula C ₁₁ H ₂₃ COOH
C ₁₃ H ₂₇ COOH
C ₁₅ H ₃₁ COOH
^C 17 ^H 35 ^CH

Unsaturated fatty acids (C _n H _2n-2 ^ O ₂ )

Surname formula Fp- ( ⁰ C) Erucic acid
Elaidic acid,
Eleostearic acid
Angelica acid CH ₃ (CH ₂ ) ₇ CH = CH (CH ₂ ) _{1] L} COOH
_CH3 (CHa) ₇ CH = CH (CHj) ₇ COOH
CH ₃ (CHa) ₃ CH = CHCH = CHCH = CH (CHa) ₇ COOH
CH ₃ CH = C (CH ₃ ) COOH 35
51 to 52
49 to 50
45

In addition, the fatty acids can have substituents such as hydroxyl groups, carbonyl groups, chlorine atoms etc., unless the melting point or the solubility properties are disadvantageous be changed.

Preferred fatty acids are the straight chain, naturally occurring saturated fatty acids, such as Myristic acid, palmitic acid and stearic acid as these are cheap, completely non-toxic and practical or are completely odorless.

The plasticizers used are the same as for the fatty acid esters. Also the proportions Fatty acid to plasticizer, the preferred mode of application and the appropriate particle sizes as well as the way in which these are achieved are as with those.

Example 4

A strand as in Example 1 is treated in an analogous manner with a solution of equal parts by weight of stearic acid and glycerol triacetate sprayed (inside the spray gun) at a temperature of 70 ° C is held. This solution is made by adding the stearic acid to the liquid glycerol triacetate and Warming the mixture to 60 to 70 ° C is obtained. As the acid melts, it dissolves in the glycerol triacetate and gives a homogeneous solution.

A strand of 62% cellulose acetate fibers, 19% stearic acid and 19% glycerol triacetate is obtained, which is processed into filter rods 90 mm long and 25.5 mm in circumference. After half an hour When stored at 27 ° C, the sticks are quite solid. Some of them are opened and under a microscope considered. It turns out that essentially all fibers have a rough and irregular surface, which is due to the fact that the stearic acid is on the fibers as a fine powder which is firmly bound to the fibers. Some of the rods come in filter tips of 15 mm Cut to length and tested as described in Example 1. The results are shown in Table 2.

Table 2
Milligrams of nicotine and tar when smoking cigarettes with and without filters

Cigarettes
without filter
(85 mm total
length) Cigarettes
with acetate filters
(85 mm total
length) Cigarettes
with acetate filters
and a salary
of 19 per cent. glycerine
triacetate
(85 mm total
length) Cigarettes
with acetate filters
and a salary
of 19% glycerine
triacetate and 19%
Stearic acid
(85 mm total
length) Pressure drop in cm 7.8
170
29 9.0
150
25th
11.8
13.8 8.8
156
26th
8.3
10.4 9.8
106
19th
37.5
34.5 Milligrams of tar from ten cigarettes ..
Milligrams of nicotine from ten cigarettes
Tar decrease due to the filter in%
Nicotine decrease as a result of the filter in%

1 07y

10

There are also comparison filters without additives and those with a glycerol triacetate content of 19% manufactured and tested solely from the same fiber material. There are also ten filterless "King-size" cigarettes (brand A), which are not shortened by 15 mm, with the help of the smoke machine also smoked to stub lengths of 35 mm. All results are summarized in Table 2.

According to a further embodiment of the invention, higher molecular fat ίο serve as an additive alcohols.

In order to bring about the effect according to the invention, the dissolved alcohol must be at room temperature solid, but liquid when heated to around 50 to 100 ° C. It is advisable to choose an alcohol, ig which is miscible with the plasticizer in all proportions in the molten state and at room temperature, d. H. below 40 ° C, in which plasticizer is essentially insoluble. Preference is given to non-toxic, obtainable from natural products, in particular from corresponding naturally occurring esters derived fatty alcohols, e.g. E.g .: stearyl alcohol (octadecanol, melting point = 58 to 60 ° C) and ceryl alcohol (hexadecanol, Mp = 49 to 50 ° C). - The fatty alcohols can also be replaced by hydroxyl, carbonyl, chlorine, etc. be substituted, provided that this does not interfere with the melting point or the solubility properties will.

The hot solvents used to spray the alcohols onto the cellulose acetate strand Cellulose acetate plasticizers are chosen as discussed above. Also the proportions of higher molecular weight Alcohol to plasticizer, the preferred mode of application and the appropriate particle sizes and the manner in which this is achieved are as indicated above.

Example 5

A strand as in Example 1 is treated in an analogous manner with a solution of equal parts by weight Stearyl alcohol and glycerol triacetate are sprayed (inside the spray gun) at one temperature is kept at 70 ° C. After this treatment it consists of 68% cellulose acetate, 16% stearyl alcohol and 16% glycerol triacetate. It is now processed, tested and analyzed according to Example 4. the Results are shown in Table 3.

Table 3 Milligrams of nicotine and tar from the smoke of cigarettes with and without filters

Cigarettes
without filter
(85 mm total
length) Cigarettes
with acetate filters
(85 mm total
length) Cigarettes
with acetate filters
and a salary
of 19 per cent. glycerine
triacetate
(85 mm total
length) Cigarettes
with acetate filters
and a salary
of 16% glycerin
triacetate and 16%
Stearyl alcohol
(85 mm total
length) Average pressure drop in cm ..
Milligrams of tar from ten cigarettes ..
Milligrams of nicotine from ten cigarettes
Tar decrease due to the filter in ° / o
Nicotine decrease as a result of the filter in% 7.8
170
29 9.0
150
25th
11.8
13.8 -8.8
156
. 26th
8.3
10.4 10.0
112
20th
34.0
31.0

The above examples show different combinations of solid materials with different ones Plasticizers that can be applied to the fibers so that they carry solid particles and result in improved filters; however, other combinations also give good results. So had z. B. a spray mix of 55% triacetin plasticizer and 45% of the molten solids proven. The melted solids consisted of 80% of a distilled glycerol monostearate, obtained by transesterification of naturally occurring fat, and from 20% ■ of a hydrogenated acetylated one Monoglycerides in a similar manner. The application of this combination appears to have the binder effect to reinforce the fibers.

The percentages mentioned above relate to percentages by weight. There will be those procedures preferred, after which the solid and the plasticizer are premixed and premelted, because this advantageously saves equipment and process steps. Of the Solids, the esters and alcohols are given 65 d) moved glycerol monostearate and hydrogenated castor oil from the esters, from the alcohols the stearyl alcohol.

Although the combinations of plasticizers and waxy additives described above are found in In many cases, preference can be given to the invention also use more common and cheaper wax materials, 'e.g. certain vegetable, Petroleum, insect, animal, mineral and synthetic waxes. So come z. B. in question:;

a) Carnauba wax, a well-known vegetable wax that consists mainly (about 75%) of myricylcerotate as well as small amounts of free cerotic acid and myricyl alcohol;

Paraffin, a wax made from high-boiling petroleum fractions made from a mixture of numerous saturated Hydrocarbons consists (melting range. 43 to 66 ° C, density 0.88 to 0.92 in ordinary Temperatures, "acid number = 0, saponification number = 0, soluble in benzene, ether, chloroform and Turpentine);

c) beeswax, which consists mainly of myricyl palmitate, Cerotic acid and its homologues as well as small amounts of hydrocarbons, cholesterol esters, Ceryl alcohols, pollen and resins consists of:

Spermacetwax, the well-known wax of the sperm whale, which mainly consists of cetyl palmitate, Consists of cetyl alcohol and numerous esters of high molecular weight fatty acids;

e) montan wax, a mineral obtained by solvent extraction from charcoal or lignite

909 769/130

wax, which is a monoester of a high molecular acid (physical properties: Mp = 72 to 92 ° C, density = 1.0, acid number = 15 up to 85, saponification number = 58 to 89, soluble in benzene, chloroform, naphtha and isopropyl ether);

f) Acrawax types, which are marketed by the Glyco-Products Company under the three names Acrawax, Acrawax B and Acrawax C and are complex nitrogen-containing derivatives of high molecular weight fatty acids (physical properties: melting range = 95 to 139 ° C, specific weight = 0.98 to 1.05, soluble in hot toluene, turpentine and mineral oil); ¹ S g) so-called castor wax, a hydrogenated castor oil (physical properties: melting point = 86 to 88 ° C., saponification number = 175 to 185, acid number = 2, insoluble in most solvents);

20th

h) Polyolefin waxes, high molecular weight polymers of ethylene or propylene with melting points in Range from about 105 to 110 ° C, soluble in hot benzene and toluene, but in the cold in most insoluble in organic solvents.

These waxy fat bodies (a to h) can, as described above, in the presence of plasticizers converted into a liquid state and sprayed onto the fibers in the form of droplets, or they can also be melted on their own and sprayed onto the fibers, with the plasticizer is omitted entirely. In some cases it is also advisable to use the plasticizer as described above or to be applied separately to the fibers after the wax droplets.

The denier of the fibers can range from 0.6 to 16. For some purposes a denier of 3 or below an advantage. The total denier is between 20,000 and 100,000, with a total denier from 40,000 to 50,000 is preferred.

When carrying out the method, an apparatus which is suitable is used with advantage Is jacketed and insulated to supply and retain heat, d. H. in the Spray chamber in which the spread fibers are sprayed with the plasticizer-solids mixture, all chamber surfaces are preferably heated to above the melting point of the spray mixture. In addition, naturally heated melting vessels are provided for the plasticizer and solid additive. The lines, sprayers and pumps for handling the hot solution of the additive in the plasticizer are expediently provided with jackets to retain the heat. By Such equipment will prevent sprayed droplets that have not spread on the Fibers arrive, solidify in the apparatus, so that they are rather kept in a liquid state. This liquid can then be withdrawn from the lower part of the spray chamber and returned.

As soon as the sprayed fibers leave the spray chamber, suitable ones are in the vicinity of the exit point Cooling arrangements attached so that the sprayed fibers are cooled and the sprayed out Particles solidify in the form of knots and ribs on the fiber surface. The different Rollers and the like components, which are in the vicinity of the exit point for pulling the sprayed fibers are arranged through the spray chambers, are provided with suitable scraper blades and collecting means, so that solids deposited on these rollers, scraped off, get into the collecting means and can be returned to the melting vessels.

From the description it follows that according to the invention substantial amounts of additive through a relatively simple and economical process can be incorporated into the fiber filters. It is not only possible, in a satisfactory way to apply larger amounts of additives to the fiber surface than was previously possible, but it this also enables the additives to adhere more firmly to the fibers. Since according to the Invention the use of dust is not included, one can save equipment costs and also avoid any risk of a dust explosion occurring, for example due to an electrical discharge.

As can be seen from the tables, the filter materials according to the invention have an improved one Filter effect on similar known products.

Claims (9)

Claim: 1. Filter rod and filter elements for tobacco smoke consisting of it, consisting of one .Multiple, expediently, fibers arranged in the form of a bundle of at least 10,000 pieces, preferably made of plasticized cellulose acetate, which contain an additive, characterized in that that the additive from 1 to 30, preferably more than 20 percent by weight, at most 30, preferably about 5 to 10 μ in size, solid, generally in the form of knots and Ribs bonded to the fiber surface of a particle in the range of about 35 to 100 ° C melting high molecular weight solid of waxy consistency. 2. Filter material according to claim 1, characterized in that it is higher molecular weight as an additive Contains alcohols, acids or esters. 3. Filter according to claim 1 or 2, characterized in that the additive consists of a Mixture of two or more of the compounds defined above. 4. A method for producing the filter material according to any one of claims 1 to 3, characterized in that that in order to apply the solid additive to the fibers, they are spread out with fine particles of the liquefied additive are provided and that additional material that does not adhere to the fiber surfaces, is withdrawn and returned in a liquefied state. 5. The method according to claim 4, characterized in that the additional material in molten State is applied. 6. The method according to claim 4, characterized in that the spread fibers with a a liquid mixture with a temperature of more than 50 ° C, made from a non-toxic plasticizer for the fiber material in question and 25 to 80%, preferably 40 to 70% of the additional material exists, this being chosen so that it interacts with the plasticizer at temperatures Miscible above 50 ° C, but is sparingly soluble in this below 40 ° C that the sprayed in this way Fibers are combined into a bundle and that this is optionally provided with a sleeve, cut into lengths and used for Solidification for a fraction of an hour, expediently more than 20 minutes, at temperatures is stored above 20 ° C. 7. The method according to claim 6, characterized in that that about 20 to 60% of a mixture of about equal parts plasticizer and additive material is sprayed on. 8. The method according to claims or 7, characterized characterized in that at least one of the following compounds is used as plasticizer: Glycerine di and triacetate, glycerine di and tripropionate, di (methoxyethyl) phthalate, ethyl phthalyl methyl glycolate, Triethyl citrate. 9. The method according to any one of claims 6 to 8, characterized in that a plasticizer Glycerin derivative, preferably triacetin, and, as an additive material, a stearin derivative, preferably a mixture of glycerol monostearate and hydrogenated acetylated monoglyceride is used will. 1 sheet of drawings © 909 T69 / 180: 3.6tt