Environmentally degradable cigarette filter

FIELD: tobacco industry.

SUBSTANCE: invention relates to environmentally degradable cigarette filter comprising the filtering element of the plasticized cellulose acetate tow and plug wrapping surrounding the said filtering element, which additionally comprises a weak organic acid and pH-adjusted salt of an ester encapsulated in a matrix material, at that the said pH-adjusted salt of an ester has the pH less than or equal to 8, at that the said matrix material encapsulates the said weak acid and the said pH-adjusted salt of an ester being in contact with the tow.

EFFECT: providing release of a strong acid to provide the acceleration of degrading of cellulose tow.

18 cl

2420-189669RU/015

DEGRADABLE IN the ENVIRONMENT of CIGARETTE FILTER

DESCRIPTION

The technical field

The present invention is directed to biodegradable in the environment of the cigarette filter.

The level of technology

Published application US 2009/0151738 included here by reference, discloses biodegradable cigarette filter obtained by contacting cigarette tow of cellulose acetate, in one embodiment, with a mixture of water-soluble matrix material and a combination of weak organic acids and compounds that can be hydrolyzed to a strong acid.

Compounds that can be hydrolyzed to strong acids, identified as sulfate pulp dodecyl sulphate, ascorbyl-2-sulfate, ascorbyl-2-phosphate, phosphorous pentoxide, esters on the basis of phosphorous pentoxide, cellulose nitrate, 2-ethylhexanoate, and combinations thereof. These compounds are esters of strong acids, and many are unstable (this means that they will decompose in a relatively short period of time, thus making them unsuitable for use in many application forms). Therefore, these esters are normally supplied by the industry in the form of a salt of ester. These salts esters are stable and do not decompose with vremennogo their mesolevel options. However, their stability is not possible to use them in this application.

Accordingly, the above-mentioned compounds that can be hydrolyzed to strong acids, must be modified in order to make their action in this application is more active (i.e. hydrolysis to strong acids, which, in turn, catalyze the decomposition of cellulose acetate).

The invention

Degradable in the environment, cigarette filter includes a filter element of the plasticized tow of cellulose acetate and wrap plugs surrounding the specified filter element. Weak organic acid and the pH adjusted Sol of ester encapsulate in a matrix material which is in contact with the harness. the pH-adjusted salt of ester has a pH less than or equal to 8. When the cigarette filter emit into the environment, water releases a weak acid and salt of ester of the matrix material. Weak acid hydrolyses ester, releasing a strong acid. Strong acid catalyzes the decomposition of the bundle of cellulose acetate. (Weak acid is also hydrolyzes tow of cellulose acetate, but after generated a strong acid, a strong acid becomes the dominant acid catalyst for the decomposition of tow of cellulose acetate).

Degradable in the environment of cigarette filter mainly includes a filter element (or filter cap), made of plasticized tow of cellulose acetate, the wrap plugs surrounding the filter element, and a weak organic acid and the pH adjusted Sol of ester encapsulated in a matrix material. The encapsulated materials are in contact with the harness. Each of these components will be discussed in more detail below.

Degradable in the environment, cigarette filter, as used here, relates to a cigarette filter, which will decompose under the influence of the environment outside (i.e., rain, dew, or other sources of water). The degree of decomposition is at least sufficient to convert the entire cellulose acetate or its part (in cigarette filters cellulose acetate basically has a Degree of Substitution (D.S.) of 2.0 to 2.6) in cellulose (D.S.≤1.0)and at least sufficient to convert the cellulose acetate into glucose. The period of time for such a decomposition is less than the time for decomposition of the equivalent amount of untreated cellulose acetate, and usually can be up to several months (e.g., 2-6 months or less).

Filter element, done the config of the plasticized tow of cellulose acetate, and wrap plugs are traditional. Harness acetate cellulose is a cellulose diacetate with value D.S. in the range from 2.0 to 2.6. Then they attached to the tobacco rod of a cigarette in a known manner.

Weak organic acids include ascorbic acid, citric acid, lactic acid, nicotinic acid, hydroxytrol acid (malic acid), and combinations thereof. Preferred are ascorbic acid and citric acid.

The PH-adjusted salt of ester include salt, organic sulfates and organic phosphates. Esters of strong inorganic acids can be unstable and easily decomposed, so that their applicability in the present application may be limited. Therefore, these esters stabilize transformation in their salt form. However, these inorganic salts of esters so stable that they can hardly be subjected to hydrolysis and release the appropriate strong acid. If pH adjustment inorganic salt of ester, it is somewhat less stable and hydrolyzed easier. Under the regulation of pH is assumed that some part of the metal fragment (usually sodium or potassium, but without limitation to) inorganic salts of ester, but not all of it, dissoc the range (and thus the pH of the inorganic salt of ester in the solution decreases, that is, the solution becomes more acidic). the pH should be set at a level less than or equal to 8, or in the range of pH 2.5 to 8. In yet another embodiment, the pH range may be 3-7,5. In yet another embodiment, the pH range may be from 4-7. In yet another embodiment, the pH range may be at 5.3-7. The lower the pH, the faster the decomposition; however, if the pH is too low, the instability of the compounds can have a negative impact. Additionally, the preferred organic compounds that contain numerous fragments of strong acids, because when they are hydrolyzed, they will release a greater amount of strong acid.

Such salts, organic sulfates include, but are not limited to those: hexanetriol salt hexadentate Inositol; octanethiol salt octasulphate sucrose; salt such as sulfate pulp; dodecyl sulphate; sodium salt of sulfate of glucose; ascorbylpalmitate sodium lauryl sulfate; sodium salt of sulfate, starch; octisalate sodium; and combinations thereof.

Such salts, organic phosphates include, but are not limited to those: execulive salt of Inositol hexaphosphate; disodium salt of sucrose phosphate; disodium phosphate salt of glucose; the disodium salt of ascorbylpalmitate; disodium salt lauryl state; sodium salt of starch phosphate; 2-ethylhexanoate; disodium salt of octylphosphine; and combinations thereof.

The amount of pH-adjusted salt of ester should be sufficient to stimulate the decomposition of the whole bundle of cellulose acetate or its parts with greater speed than for the equivalent raw filter element. For example, in one embodiment of the invention the duration of decomposition can be 2-6 months. The amount of pH-adjusted salt of ester will depend, for example, from: the weight of the cellulose acetate in the filter element, the desired duration of the decomposition of the filter element and the selected pH-adjusted salt of ester (named just a few factors).

For example, if the planned duration of decomposition is 2-6 months, then, in one embodiment, the amount of acid released from the pH-adjusted salt of ester can vary in the range 2-200% by weight of cellulose acetate in the filter element. In another embodiment, to achieve the same desirable results as indicated above, the amount of acid released from the pH-adjusted salt of ester can vary in the range of 5-100% by weight of cellulose acetate. In yet another additional embodiment, executed the I amount of acid, released from the pH-adjusted salt of ester can vary in the range of 10-50% by weight of cellulose acetate.

The matrix material may be any water-soluble and/or permeable material, which can be encapsulated (i.e., to contain a weak organic acid and the pH adjusted Sol of ester); but in contact with water will dissolve and/or flowing water for mixing with a weak acid and the pH adjusted salt of ester. When mixing begins acid catalyzed hydrolysis pH-adjusted salt of ester. Over time, the catalyst(-ry) migrates(s) in the filter of cellulose acetate or the cigarette and stimulate(s) the hydrolysis of the filter of cellulose acetate or butt. Encapsulation is important for at least two reasons: first, the encapsulation prevents premature hydrolysis, and, secondly, saves shelf life when stored product (filter). Water-soluble matrix material may be a cellulose acetate (D.S.=0,8 ±0,2), carboxymethylcellulose (CMC), ethylcellulose, hydroxypropylcellulose (LDCs), hypromellose (receiver array), methylcellulose, polyethylene glycol (PEG), polyvinyl acetate, polyvinyl alcohol, starch, sugar, and combinations thereof. Sugar may be glucose, with whom harotu, lactose, and combinations thereof. In many versions of the water-soluble matrix material can be a carboxymethylcellulose, hydroxypropylcellulose, hypromellose, polyvinyl alcohol, polyethylene glycol, and combinations thereof. Permeable materials may include ethylcellulose, shellac, Zein (preliminaly protein found in corn), cellulose acetate (D.S.=2,0-2,6), phthalate cellulose, porous silicone elastomers (i.e., silicone elastomers with the addition of PEG, where PEG wash the dissolution to form pores), esters of acrylic acid (for example, commercially available on the market under the trade name EUDRAGIT from the company Evonik Degussa Corp., Piscataway, new Jersey), and combinations thereof.

The amount of matrix material should be sufficient to fully encapsulate a weak organic acid and the pH adjusted salt of ester. Full encapsulation has to cover and isolate weak organic acid and the pH adjusted salt of ester so that they cannot catalyze the hydrolysis, as the water will dissolve at least part of the matrix material. Basically, the weight ratio of weak organic acid and the pH adjusted salt of ester to water-soluble matrix material can vary on what apatone of 0.75 to 4.0:1. In one embodiment, the ratio may be 2:1.

A weak organic acid and the pH adjusted Sol complex ether, and the matrix material can be in the form of coatings or particles that are in contact with the harness. See the publication of the patent document U.S. No. 2009/0151738, incorporated herein by reference.

The coating can be applied to harness cellulose acetate after fabrication of the bundle (i.e., not added to the spinning solution), and/or on the wrapper blank. In one embodiment, the mixture can be applied in the form of a coating on the harness before the formation of the filter element. For example, in a traditional machine for the manufacture of plugs the solution mixture can be nebraskan on plasticized harness before climbing harness via a headset or during it. Alternatively, after forming the filter element solution mixture may be injected (e.g., via syringe) in harness. In yet another embodiment, the mixture can be added in the form of a coating (or applied) as the line on the inner surface of the wrapper blank.

The particle can be added to the filter element during the manufacture of cigarette filter. Particle, as used here, may mean, for example: a single particle, comprising the mixture (which may be enclosed in a gelatin capsule or cover is a protective barrier coating, or without encapsulation or coating), or a pellet of a mixture or powder of a compound or a pill from a mixture (for example, the mixture separately or with traditional binding agent for tablets). The particle can be added to the cellulose acetate filter element before (or during) the formation of the filter element. For example, in a traditional machine for the manufacture of plugs particle of the mixture can be introduced into the plasticized tow before passing the harness through the headset or during it.

Alternatively, the particle contains a weak acid and the pH adjusted Sol ether complex, surrounded by an inner layer of water-soluble or water-permeable material and an outer layer of cellulose acetate having a D.S. in the range of 2.0 to 2.6, surrounding the inner layer. This design particles described in patent document U.S. serial No. 12/687912, filed January 15, 2010, incorporated herein by reference. The following describes the components of this variant.

Weak acid and the pH adjusted Sol of ester are as described previously.

The inner layer and the outer layer that surrounds and encapsulates the weak acid and the pH adjusted Sol of ester so that 1) the excess water not only washes away the weak acid and the pH adjusted Sol ether complex, and there are enough weak is th acid and the pH adjusted salt of ester over time, to catalyze the hydrolysis, 2) prevents the perception of smoke smell weak acid and the pH adjusted salt of ester, other than cellulose acetate, which can adversely affect the taste of the smoke, and 3) facilitates the binding of the particles from the thread in the loom traditional binders for harness, such as triacetin, or glycerol triacetate. The inner and outer layers may act together to regulate the release of weak acid and the pH adjusted salt of ester, and the outer layer acts to mask the taste of the weak acid and the pH adjusted salt of ester, and the inner layer, and to facilitate binding.

The inner layer is a water-soluble material or water-permeable material. These materials can be any material that can encapsulate (i.e., to contain a weak acid and the pH adjusted Sol of ester); but in contact with water will either be dissolved and thereby allow to catalyze the hydrolysis, or skip the water and then allow release of the catalyst. In the case of water-soluble material, the water will turn this material into the gel, and the gel-like material can then regulate the movement of water in the core or you are the od of the catalyst from the core. In addition, the gel-like material may swell, what then can destroy the outer layer. Encapsulation is important at least for two reasons: first, the encapsulation prevents premature hydrolysis, and, secondly, saves shelf life when stored product (filter). Water-soluble matrix material and a water-permeable material are as described above.

The outer layer is a cellulose acetate with a D.S. of 2.0 to 2.6. The cellulose acetate with a D.S. of 2.0 to 2.6 is permeable. The cellulose acetate preferably has the same or about the same D.S., and harness fibers ("about the same" means that D.S. is within ±25% D.S. tow fibers).

The number of the inner layer and the outer layer should be sufficient to fully encapsulate (or environment) of a weak acid and the pH adjusted salt of ester. Full encapsulation (or environment) has to cover and isolate the weak acid and the pH adjusted salt of ester so that they cannot catalyze the hydrolysis until the water will not penetrate through the outer layer and will not dissolve at least part of the water-soluble material (or will penetrate through the permeable material of the inner layer. For example, the inner layer may vary in the range of 5-100% by weight of poorly the acid and the pH adjusted salt of ester, or 5-30% by weight in another embodiment. The outer layer may vary in the range of 5-100% by weight or 5 to 30% by weight in another embodiment. Alternatively, the number of the inner layer and the outer layer can be made comparable with the degree of delay, that is, "a period of half-transformation". The period of half-transformation represents the time required for the catalytic material lowered the pH value of the solution to ½ of the initial pH. The following data 1 ml of water is approximately equivalent to that of a standard cigarette filter. In the present invention the period of half-transformation of the material should be at least 25 minutes, or to be in range at 25 ÷ 1000 minutes, or 50-500 minutes, or 75-300 minutes.

EXAMPLES

In the following examples, the influence of regulating the pH of the inorganic salt of ester and temperature on the rate of decomposition of cigarette filters from cellulose acetate.

the pH-adjusted sodium salt of sulfate cellulose obtained as follows:

1. 2 grams of sodium salt of sulfate pulp was obtained in the Fischer Scientific (Acros)was dissolved in 200 ml of demineralized water with stirring. Thus prepared 1%solution.

2. Immediately after the dissolution of the measured value of pH using pH meter, at the same time the I with continuous stirring of the solution. The PH of the solution was equal to 9.

3. Odnokolernyh the hydrochloric acid solution was added dropwise using a syringe with a capacity of 1000 microlitres until he received the pH=7.

4. Repeated stages 1-3 to obtain a 1%solution of sulphate pulp with a pH of 5 and 3.

5. The control solution had 2 grams of sodium salt of sulfate cellulose dissolved in 200 ml of demineralized water with stirring.

6. Each of the four solutions, labeled "pH=9", "pH=7", "pH=5 and pH=3", added 2 grams of citric acid.

Filter rods were treated with the above solutions as follows:

1. He removed the paper from 80 plasticized filter rods (24,45 mm × 102 mm).

2. These cores were divided into 4 groups of 20.

3. 20 rods immersed in a solution with pH=9 and left before saturation.

4. Extracted cores using tweezers, left to drip and put on the plastic sheet to dry in the air (3-4 days).

5. Repeated stage 3-4 for samples "pH=7", "pH=5 and pH=3".

6. Then dry the cores were subdivided into groups of 10 rods and put in jars.

7. Banks marked as follows:

The rods were tested for the loss of degree of substitution (DS) with time. The value D.S. calculated by retention time on the basis of known standard samples of cellulose acetate. Used high-performance liquid chromatography (HPLC), based on the work of the author T.R. Floyd, namely, Floyd, T.R., "Chemical Characterization of Cellulose Acetate by Non-exclusion Liquid Chromatography ("Chemical characterization of cellulose acetate using exclusional liquid chromatography")",J. Chromatogr. 1993,that 629, pages 243-254. The advantage is that the value D.S. can be calculated from small samples (<0.3 g). This provides the main advantage compared with the traditional method of titration of a solution of 2.0 g of the sample (ASTM D871-91). Method HPLC is not as accurate as the method in accordance with ASTM; however, the HPLC method easily tracked losses D.S. HPLC analysis is limited to the lower value D.S. at 1.5. This is because the cellulose acetate with D.S. below 1.5 is not soluble in acetone. Tables 1-3 summarize the results of HPLC-tested. Table 3 compares the gradients of the regression equations. Data show that the lower the initial pH of rest the RA sodium salt of sulfate pulp, the faster hydrolyzed (broken) filter rod of plasticized cellulose acetate. In addition, the rate of decomposition increases with temperature.

The percentage insoluble in acetone material was determined for the sample after 56 days. The samples were processed according to the following procedure to obtain insoluble in acetone material and are listed in table 4.

1. The sample size of 20 mm were cut from the treated filter rod, and weighed.

2. The sample was washed with water to remove citric acid, sodium salts of sulfate pulp, acetic acid and any residual salts.

3. The samples were left to dry in air for 3 days before check their weight.

4. The samples were dissolved in 10 ml of acetone, then filtered and washed with excess acetone.

5. Otti trevanny the material was left to dry in the air before you check its weight.

The data in table 4 show an inverse relationship between initial pH of the sodium salt of sulfate pulp and the percentage content of the insoluble in acetone substances. The lower the initial pH of the sodium salt of sulfate pulp, the higher the percentage insoluble in acetone substances. The temperature increase has a direct impact on the percentage insoluble in acetone substances. These data demonstrate that the filter rods from plasticized cellulose acetate decomposed or hydrolyzed faster when processed pH-adjusted sodium salt of sulfate pulp. The material of sulphate pulp with a lower pH is more sensitive to hydrolysis catalyzed by an organic acid. Hydrolysis releases the sodium hydrosulphate, salt of a strong mineral acid with the valuepKa=1,9. The sodium hydrosulphate becomes dominant is utalization, which enhances the decomposition or hydrolysis filters of plasticized cellulose acetate. This allows for flexible design in terms of how fast it is desirable decomposition of discarded cigarette filters/butts.

The present invention can be implemented in other forms without going beyond its meaning and essential features, and, accordingly, in terms of defining the scope of the invention should focus more on the points of the attached patent formula, rather than the foregoing description.

1. Degradable in the environment of cigarette filter containing a filter element of the plasticized tow of cellulose acetate and wrap plugs surrounding the specified filter element which further includes:
weak organic acid and the pH adjusted Sol of ester encapsulated in a matrix material, and specified pH adjusted Sol complex ester has a pH less than or equal to 8, and the specified matrix material encapsulates the specified weak acid and a specified pH-adjusted salt of ester being in contact with a bundle.

2. Cigarette filter according to claim 1, wherein said pH is in the range 1-8.

3. Cigarette filter according to claim 1, wherein said pH is in the range 4-7.

4. sigarety filter according to claim 1, in which the specified pH-adjusted salt of ester includes such salts, organic sulfates and/or organic phosphates.

5. Cigarette filter according to claim 4, in which the specified pH adjusted Sol organic sulfate selected from the group consisting of: ascorbylpalmitate, sulfate pulp, sulfate glucose, hexadentate Inositol, lauryl, octisalate, sulfate starch, octasulphate sucrose, and combinations thereof.

6. Cigarette filter according to claim 1, which indicated a weak organic acid selected from the group consisting of ascorbic acid, citric acid, lactic acid, nicotinic acid, hydroxyethanoic acid (malic acid), and combinations thereof.

7. Cigarette filter according to claim 1, wherein said matrix material is a water-soluble material and/or permeable material.

8. Cigarette filter according to claim 7, wherein said water-soluble matrix material selected from the group consisting of: cellulose acetate (D.S.=0,8±0,2), carboxymethyl cellulose, ethyl cellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, methylcellulose, polyethylene glycol, polyvinyl acetate, polyvinyl alcohol, starch, sugar, and combinations thereof.

9. Cigarette filter according to claim 7, wherein said permeable material is selected from the group consisting of: ethyl is ellulose, shellac, Zein, cellulose acetate (D.S.=2,0-2,6), phthalate cellulose, porous silicone elastomers, esters of acrylic acid, and combinations thereof.

10. Degradable in the environment, cigarette filter that includes a filter element of the plasticized tow of cellulose acetate and wrap plugs surrounding the specified filter element which further includes:
a particle comprising a weak acid and the pH adjusted Sol complex ether, and the specified pH adjusted Sol complex ester has a pH less than or equal to 8, is surrounded by an inner layer of water-soluble or water-permeable material and an outer layer of cellulose acetate having a D.S. in the range of 2.0 to 2.6, surrounding this internal layer.

11. The cigarette filter of claim 10, wherein said pH is in the range 1-8.

12. The cigarette filter of claim 10, wherein said pH is in the range 4-7.

13. The cigarette filter of claim 10 in which the specified pH-adjusted salt of ester includes such salts, organic sulfates and/or organic phosphates.

14. Cigarette filter according to item 13, in which the specified pH adjusted Sol organic sulfate selected from the group consisting of: ascorbylpalmitate, sulfate pulp, sulfate glucose, hexadentate Inositol, lauryl, Attila is that, sulfate starch, octasulphate sucrose, and combinations thereof.

15. The cigarette filter of claim 10, in which indicated a weak organic acid selected from the group consisting of ascorbic acid, citric acid, lactic acid, nicotinic acid, hydroxyethanoic acid (malic acid), and combinations thereof.

16. The cigarette filter of claim 10, wherein said matrix material is a water-soluble material and/or permeable material.

17. Cigarette filter according to item 16, wherein said water-soluble matrix material selected from the group consisting of: cellulose acetate (D.S.=0,8±0,2), carboxymethyl cellulose, ethyl cellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, methylcellulose, polyethylene glycol, polyvinyl acetate, polyvinyl alcohol, starch, sugar, and combinations thereof.

18. Cigarette filter according to item 16, wherein said permeable material is selected from the group consisting of: ethyl cellulose, shellac, Zein, cellulose acetate (D.S.=2,0-2,6), phthalate cellulose, porous silicone elastomers, esters of acrylic acid, and combinations thereof.