WO2011107311A1

WO2011107311A1 - Hygienic product with antimicrobic and antifunguses properties

Info

Publication number: WO2011107311A1
Application number: PCT/EP2011/051314
Authority: WO
Inventors: Ara Arshavirovich Abramyan; Mikhail Mefodievich Afanasyev; Viacheslav Ivanovich Beklemyshev; Konstantin Vitalievich Filippov; Igor Ivanovich Makhonin; Umberto Orazio Giuseppe Maugeri; Vladimir Aleksandrovich Solodovnikov
Original assignee: Closed Stock Company "Institute Of Applied Nanotechnology"; Fondazione Salvatore Maugeri Clinica Del Lavoro E Della Riabilitazione; Sib Laboratories Limited
Priority date: 2010-03-03
Filing date: 2011-01-31
Publication date: 2011-09-09
Also published as: RU2419455C1

Abstract

Hygienic products such as hygienic towels, hygienic napkins, pampers and the like comprising at least one layer of adsorbing dry cellulose mass, previously treated with a water system of biocide consisting of nanoparticles of a bentonite powder intercalated by ions of silver and/or copper and also containing a copolymer on the basis of a hydrolyzed vegetal protein, whose ending or lateral amino groups are linked with silanol groups or polyvinylpirrolidone. The new products may contain also a superabsorbing layer on the basis of sodium polyacrylate or of a copolymer of polyacrilamide.

Description

HYGIENIC PRODUCT WITH ANTIMICROBIC AND ANTIFUNGUSES PROPERTIES

Technical field

The invention concerns medicine and hygiene, in particular hygienic products such as: nappies (pampers), sanitary towels, tampons, adsorbing linen (absorbing sheets), toilet papers, hygienic towels, hygienic napkins possessing adsorbing properties concerning various liquids.

There is a problem of reproduction of bacteria, funguses and the like under the influence of urine, menstrual liquids etc. when such products are used. Reproduction of pathogenic microorganisms occurs essentially in the adsorbing material, preferably in the dry cellulose masses applied for manufacturing these products.

State of the art

A number of patents concerned with the creation of hygienic products on the basis of adsorbing materials possessing antibacterial, antifunguses, antiinflammatory and deodorizing properties are known, including:

- a product obtained by applying functional substances such as the antibiotic imidazole derivatives, Triclosan and the like, in the adsorbing layer of the same (patent RU N. 2303973, publ. 2007);

- a product obtained by injection of superabsorbing polymers in a dry cellulose mass (on the basis of the dispersed cellulose), for example sodium polyacrylate or/and a copolymer of polyacrylamide, regulating absorbing ability and decreasing unpleasant smells (patent RU N. 2345748, publ. 2009);

- a product having improved absorbing properties due to the use of dry cellulose obtained in a process of defibering with use of bentonite nanoparticles for obtaining a filament (threadlike) structure from the cellulose mass (patent US 6918992, publ. 2005). The above mentioned inventions do not provide the solution of the problem of creating a hygienic product with an adsorbing material on the basis of dry cellulose masses possessing antibacterial, antifunguses, anti-inflammatory and deodorizing properties, by application in them of functional substances which are satisfactory for cost and biological safety.

The technical specification of the patent RU N. 2371156, publ. 2009 is known. This patent is chosen as the closest prior art in respect to the declared invention. In the given patent a hygienic product with antimicrobic and antifunguses properties is described. It contains at least one adsorbing layer on the basis of the dry cellulose mass obtained after processing with a biocide consisting of a water system on the basis of nanoparticles of a bentonite powder intercalated by ions of silver (Ag⁺) and/or copper (Cu²⁺) with a quantity of metal in the powder of 2,0-8,0% b.w..

The hygienic product has got prolonged antimicrobic and antifunguses properties and the biological safety peculiar to medical products by realization of said invention, due to the adsorbing layer processed with the named system of biocide.

However it is not provided uniform distribution of bentonite nanoparticles on the surface of the fibres, when processing the cellulose mass with a water system of the specified biocide. As a result the speed of absorption and distributions of moisture in the adsorbing layer is decreased, due to insufficient or superfluous deposition of bentonite particles on the fibres. It worsens its integrated absorbing ability and, as a whole, operational characteristics of the product are worsened, including antimicrobic and antifunguses properties of prolonged action. Disclosure of the invention

The problem solved by the present invention consists in the creation of a hygienic product having, as technical result, improved operational characteristics, due to increase of absorbing ability of the adsorbing layer, with simultaneous improvement of its antimicrobic and antifunguses properties of prolonged action.

The hygienic product with antimicrobic and antifunguses properties, containing at least one adsorbing layer of a dry cellulose mass obtained after processing with a biocide water system on the basis of nanoparticles of a bentonite powder intercalated by ions of silver (Ag⁺) and/or copper (Cu²⁺), with a quantity of metal in the powder of 2,0-8,0% b.w., is used for the solution of the technical problem. According to the present invention a dispersed cellulose with a density of 100-800 kg/m³ is used as the cellulose mass. A copolymer with a molecular weight from about 18000 up to 500000, on the basis of a modified hydrolized vegetal protein is added in the water system of biocide as binding agent. Silanol groups or polyvinylpirrolidone are linked to ending or lateral amino-groups of the protein. The components, copolymer : bentonite powder : water : dispersed cellulose, are used in the following ratios, namely: (4- 10^~3- 15- 10^"3) : (4· 10^"3-15· 10 ³) : (0,5-2,5) : 1 part in weight, by working at an equal ratio of copolymer : bentonite powder in the water system.

According to the invention as the copolymer a copolymer with molecular weight about 18000 or/and about 500000, on the basis of hydrolized fibers of wheat is used. Silanol groups are linked to ending or lateral amino-groups of the protein at a ratio of copolymers in the mix of 1 : 1.

According to the invention a copolymer with molecular weight 3000 on the basis of a hydrolized protein of soya is used as the copolymer. Silanol groups are linked to ending or lateral amino-groups of this protein. A copolymer with molecular weight about 40000 on the basis of a hydrolized protein of wheat is used in addition or in alternative. Polyvinylpirrolidone is linked to ending or lateral amino-groups of this protein. The ratio of the two copolymers in a mix is 1 : 1.

According to the invention the dispersed cellulose with density not more than 300 kg/m³ is preferably used.

According to the invention the dispersed cellulose contains in addition a superabsorbing polymer on the basis of sodium polyacrylate or a copolymer of polyacrylamide, in amount 10-60% b.w. on the dry cellulose weight.

According to the invention a bentonite powder with the size of particles not more than 100 nanometers is used.

According to the invention bentonite powders intercalated by ions of silver or/and copper, at amount of metal in the powder of no more than 6% b.w., are used. The ratio of powders in a mix is accordingly 1 : (0,3-0,5).

According to the invention deionized water is used.

According to the invention the product contains a liquid-tight layer on the basis of a laminated material.

According to the invention the product contains a permeable layer for a liquid, manufactured from a nonwoven material.

According to the invention the product is manufactured as a nappy, either a sanitary towel or a tampon.

According to the invention the product is manufactured as a toilet paper, either a hygienic towel or a hygienic napkin.

At realization of the invention, operational properties of a hygienic product are improved due to obtaining an adsorbing layer from the dry dispersed cellulose, processed with a water system containing a biologically safe biocide and a copolymer on the basis of a hydrolized vegetal protein. The product is improved due to increase of absorbing ability of the adsorbing layer and due to improvement of prolonged action of antimicrobic and antifunguses properties.

By analysing the prior art were not found patents with a set of characteristics corresponding to those declared in the present application and providing the results described above.

The analysis of the technical state of the art testifies the conformity of the present patent application to the criteria of "novelty" and "degree of inventiveness".

The technical content of the present application can be industrially realized by using known technological processes, equipments and materials generally used for manufacturing products such as nappies and sanitary towels similar to them.

Detailed description of the invention

The main points of the invention are explained with reference to selected raw components for manufacturing a hygienic product, by means of examples of its obtainment and results of tests.

For manufacturing a hygienic product according to the invention the process equipment, commodity products and known technological processes are used, namely:

I) - biocide as nanoparticles of a bentonite powder intercalated by ions of silver (Ag⁺) and copper (Cu²⁺), with a content of the named metals of no more than 6% b.w.. The powder is obtained according to known patents (see patent RU N. 2330673);

The biocide is obtained by using:

- bentonite (montmorillonite) in Na-form as the clay mineral, possessing the highest capacity of cation exchange among clay minerals (up to 150 mg eqv/100 g); - 15-20% water solutions of silver nitrate (AgN0₃) and copper sulphate (CuS0₄); sodium chloride (NaCl); deionized water;

- a two stage technological process; at the first stage enrichment of bentonite by ions of sodium and cleaning (washing in deionized water, filtering, drying) is carried out; at the second stage the process of intercalation (modification) of the obtained semi-finished bentonite by ions of silver and copper obtained from the mentioned solutions of salts of silver and copper is carried out. The obtained products are cleaned from salts of sodium, dried and grinded. Bentonite powders intercalated by ions of Ag⁺ and Cu²⁺ have a size of the particles of no more than 100 nanometers, which is preferable for realization of the invention. As a matter of fact with nanoparticles of a bentonite powder having a size of more than 100 nanometers, the efficiency of their deposition on the fibres of the dispersed cellulose worsens;

II) - dispersed cellulose masses with a density of 167 kg/m³ and 270 kg/m³ at initial humidity 7-10%; manufacturer Recyc PHP Inc. (Canada);

III) - granules of a superabsorbing polymer on the basis of sodium polyacrylate with size of the particles 75-800 nanometers, bulk density 400- 700kg/m³, pH 4,9-6,5; supplier Recyc PHP Inc. (Canada), manufacturers DOW, BASF;

IV) - a granulated copolymer with molecular weight from 3000 up to 500000 Mw, on the basis of modified hydrolized vegetal protein. Silanol groups or polyvinylpyrrolidone are linked to ending or lateral amino-groups of this protein. It is preferable to use a copolymer of hydrolized protein of wheat with bound silanol groups:

- Coltide HSi or Crodasone W with a molecular weight of no more than 500000 Mw or Keravis with a molecular weight of no more than 18000 Mw or a mix of the mentioned products, i.e. products of the company Croda (GB). These products are preferable for decreasing the costs of manufacturing hygienic products. They combine in themselves unique functionalities of both molecular groups in one component, due to complex polymeric structure of albuminous and siliceous functional groups.

The following copolymers of the company Croda (GB), similar in the functionalities, can be used as the copolymer:

- the copolymer on the basis of the modified hydrolized protein of soya with linked silanol groups; molecular weight is not less than 3000 Mw;

- the copolymer on the basis of the modified hydrolized protein of wheat, with polyvinylpyrrolidone linked to ending or lateral amino-groups, for example the product Hydrotriticum PVP (molecular weight 40000 Mw).

The named products provide air-conditioning of fibres, decrease their "tangling" and increase hydrophilia of fibres.

The specified functionalities of the above products have determined their choice for a water system of biocide intended for processing of a cellulose mass, to obtain the adsorbing layer of a hygienic product.

The percentages on weight of the specified copolymers, declared in the present invention are optimum. Sorption of nanoparticles of bentonite on fibres of cellulose masses worsens at decrease of their amount in water system of biocide while increase in percentage leads to increase in costs for obtaining of an adsorbing layer and to essential deterioration of its physicomechanical parameters.

Realization of the invention by changing the structure of used components and their specified ratios, will lead to deterioration of operational properties of the hygienic product made according to the invention or to increase in cost of the process for obtaining it.

Realization of the invention is explained by concrete examples. Hygienic products, for example nappies (pampers) and sanitary towels, traditionally have the top layer of punched nonwoven material (such as "spanbod", "thermobond"), the bottom layer from a liquid-tight microporous ("breathing") polyethylene film or a nonwoven material (such as "spanbod", "thermobond") laminated with a microporous polyethylene film and, located between the specified layers, at least one adsorbing layer.

Examples for obtaining an adsorbing layer

Sample 1.

Used materials:

- a dry dispersed cellulose with density - 270 kg/m³, initial humidity - 8 % and weight - 60 g;

- nanoparticles of a bentonite powder intercalated by ions of Ag⁺ - 0,3 g; copolymer on the basis of the product Keravis with molecular weight of about 18000 Mw - 0,3 g; deionized water volume - 60 ml.

The dispersed cellulose was processed (for example by splashing) with the water system of biocide and with the copolymer. Then the obtained product was dried up to its initial humidity. An absorbing layer on the basis of dry dispersed cellulose, with weight

60,50 g, was obtained.

Sample 2.

Used materials:

- a dry dispersed cellulose with the density - 270 kg/m³, initial humidity - 8% and weight - 60 g;

- nanoparticles of a bentonite powder intercalated by ions of Ag⁺- 0,3 g, copolymer - 0,3 g, deionized water at volume - 60 ml.

As the copolymer a mix of copolymers in the same ratio was used:

- a copolymer on the basis of a modified hydrolized protein of soya with molecular weight not less than 3000 Mw; - a copolymer on the basis of a modified hydrolized protein of wheat, i.e. the product Hydrotriticum PVP with molecular weight 40000 Mw.

Processing of the dispersed cellulose is similar to the Example 1. After drying, the product, with additionally entered superabsorbing polymer on the basis of sodium polyacrylate - 6,1 g, is obtained.

The adsorbing layer on the basis of the dispersed cellulose with weight W₂=66,50 g is obtained.

Sample 3 - control.

Used materials:

- nanoparticles of a bentonite powder intercalated by ions of Ag⁺ - 0,3 g, deionized water - 60 ml.

Processing of the dispersed cellulose with water system of biocide is similar to the Example 1. After drying the adsorbing layer on the basis of the cellulose with weight W₃=60,15 g is obtained.

Examples 1-3 testify that the use of a water system of biocide and a copolymer (Examples 1 and 2) for treatment of the dispersed cellulose, in comparison with a product according to the Example 3, promotes increase in sorption activity of nanoparticles of bentonite on fibres of the cellulose.

The products obtained according to the Examples 1-3, were estimated on antimicrobic and antifunguses properties by applying the technique described in the patent RU N. 2371156.

Determination of growth of bacterial colonies was carried out during 24 hours at a temperature of 36-37°C. Absence of growth of microorganisms on membrane filters within 8 hours was established in result. Filters have been processed by washouts from the samples of the Examples 1 and 2.

Presence of growth of microorganisms within 3 hours was established at processing of membrane filters by washouts from the sample according to Example 3.

The results of the researches testify that operational characteristics of a hygienic product according to the present invention are improved in so far as prolonged action of antimicrobic and antifunguses properties are concerned. What demonstrates the expediency of application of the water system containing the specified biocide and the copolymer for obtaining an adsorbing layer.

The products obtained by the Examples 1-3 were evaluated in respect to time of adsorption - 1 (sec), and absorbing ability-Y (g/g).

Y = (B-W)AV,

where B - weight of the sample after absorption of the liquid environment, W- dry weight of the samples obtained in the Examples 1-3.

Time of adsorption (speed of absorption) determines the time of full absorption of a liquid by an adsorbing sample. Absorbing ability (volume) determines the amount of a liquid absorbed by an adsorbing sample, at a rate for one gram of adsorbing material of a sample.

The given parameters were estimated by SCAN-C 33:80, technology accepted in the European countries for determination of adsorptive properties of cellulose and paper.

For the tests were used:

- the equipment for laboratory researches with the system of automatic measurement of time of adsorption; - the samples from the adsorbing products obtained by the Examples 1-3, in diameter of 50 mm and weight of 3 g each.

The equipment comprises the container for a liquid, adjusting unit with a microporous lining for accommodation of a sample, the loading device working on the tested sample and having electrodes which are connected to the control and measuring block for recording of time of adsorption through contact of electrodes with a liquid. Measurements were carried out at room temperature.

In order to increase reliability of measurements, a water solution of salts of sodium and potassium has been used in the container of the equipment. Their content in one litre of deionized water was the following: NaCl - 6,0 g, KH₂P0₄ - 2,5 g, Na₂HP0₄ - 2,0 g.

The following data were established, as a result of test, on the basis of the average data obtained from three similar samples of the Examples 1-3:

sample by the example 1 : t = 1,9 sec;

11,5 g/g

sample by the example 2: t = 2,1 sec; Y₂= 15,3 g/g

sample by the example 3: t = 2,6 sec; Y₃= 9,1 g/g

The results of the tests demonstrate that:

the hygienic product according to the invention, with the adsorbing layer of dry dispersed cellulose, obtained after processing with a water system comprising a biocide on the basis of nanoparticles of a bentonite powder intercalated by ions of silver and/or copper, and the specified copolymer, has improved operational characteristics in respect of the time of adsorption, absorbing ability of the adsorbing layer and prolonged action of antimicrobic and antifunguses properties.

Claims

1. Hygienic product with improved adsorbing, antimicrobic and antifunguses properties, containing at least one adsorbing layer consisting of a dry cellulose mass previously processed with a water system of biocide containing nanoparticles of a bentonite powder intercalated by ions of silver (Ag⁺) and/or copper (Cu²⁺), and a copolymer on the basis of a hydrolized vegetal protein whose terminal and lateral amino-groups are linked to silanol groups or polyvinylpirrolidone.

2. Hygienic product according to claim 1, wherein the cellulose mass is derived from a dispersed cellulose mass with a density of 100-800 kg/m³.

3. Hygienic product according to claim 2, wherein the cellulose mass is derived from a dispersed cellulose mass with a density of 300 kg/m³.

4. Hygienic product according to claim 1, wherein the nanoparticles of bentonite powder contain from 2,0 to 8,0% by weight of (Ag⁺) and/or (Cu²⁺).

5. Hygienic product according to claim 4 wherein the amount of metal in the bentonite powder is no more than 6% b.w..

6. Hygienic product according to claim 4, wherein when both (Ag⁺) and (Cu²⁺) are present in the powder, their ratio is of 1 : (0,3-0,5).

7. Hygienic product according to claim 1, wherein the nanoparticles of bentonite powder have a size of no more than 100 nanometers.

8. Hygienic product according to claim 1 wherein copolymer on the basis of hydrolyzed fibers of wheat is used, with silanol groups linked to ending or lateral amino groups of the protein, having a molecular weight of about 18000 or/and 500.000.

9. Hygienic product according to claim 1, wherein a copolymer on the basis of a hydrolyzed protein of soya is used, with silanol groups linked to ending or lateral amino-groups of the protein, having a molecular weight of about 3000.

10. Hygienic product according to claim 1, wherein a copolymer on the basis of hydrolyzed protein of wheat is used, having polyvinylpirrolidone linked to ending or lateral amino-groups of the protein and a molecular weight of about 40000.

11. Hygienic product according to claim 9 and 10 wherein the two copolymers are used in admixture.

12. Hygienic product according to claim 1 wherein the copolymer has a molecular weight comprised between about 18000 and about 500.000.

13. Hygienic product according to claim 1 further comprising granules of superabsorbing polymer on the basis of sodium polyacrylate with size of the particles 75-800 nanometers and bulk density 400-700 kg/m³.

14. Hygienic product according to claim 1, wherein the ratio of the components: copolymer: bentonite powder: water: dispersed cellulose is of (4- 10 ³ - 10- 10^"3) : (4- 10 ³ - 10- 10^"3) : (0,5-2,5) : 1, the ratio of copolymer and bentonite powder in the water system being always the same.