CN114073921A

CN114073921A - A kind of composite microsphere and its preparation method and application

Info

Publication number: CN114073921A
Application number: CN202010796063.8A
Authority: CN
Inventors: 喻学锋; 钟柏华; 康翼鸿
Original assignee: Shenzhen Institute of Advanced Technology of CAS
Current assignee: Shenzhen Institute of Advanced Technology of CAS
Priority date: 2020-08-10
Filing date: 2020-08-10
Publication date: 2022-02-22

Abstract

The invention relates to a composite microsphere and a preparation method and application thereof, and specifically discloses a composite microsphere. The composite microsphere has a shell layer formed by cross-linked polysaccharide, the shell layer contains active ingredients, and the surface of the shell layer is It is decorated with metal components and a surface charge-rich composite microsphere. The surface charge-rich composite microsphere shell layer also includes a charge-rich film, and the charge-rich film is obtained by layer-by-layer self-assembly of polyelectrolytes. The invention creatively combines polysaccharide substances, natural antimicrobial agents and metal components, exerts its synergistic advantage, can change the surface properties of fabrics, and significantly enhance the antimicrobial effect of fabrics; it has excellent washing resistance and wide application range , can be used for antimicrobial finishing of different fabrics; meanwhile, it has good biocompatibility.

Description

Composite microsphere and preparation method and application thereof

Technical Field

An antimicrobial composite microsphere for fabric after-finishing and a preparation method and application thereof, belonging to the technical field of dyeing and finishing processing in cotton and wool textile industry.

Background

In modern life, textiles are widely applied as an industrial product, and the problems of insect pests caused by microorganisms, cross infection caused by germs, peculiar smell generated by fabrics and the like exist all the time, so that the problems are urgently needed to be solved in the development of textiles. In addition, discoloration, coloration and loss of functional properties of textiles are also the result of microbial destruction. Recently, antibacterial textiles have become an important field of medical and health applications, and there is a great demand for non-toxic and environment-friendly antibacterial materials. Synthetic fungicides have been widely reported as polyhexamethylene biguanide (PHMB), Quaternary Ammonium Compounds (QACs), metals (including metal oxides and salts), triclosan, n-halamine, and the like. Natural biocides (aromatic compounds, dyes, essential oils), chitosan, antimicrobial peptides (AMPs) and the like are substances mainly comprising plant extracts.

First, antibacterial substances have been mainly used in the medical and pharmaceutical industries. However, in recent years, antibacterial substances have been increasingly used for treating textile fibers. Other fields include food packaging and food storage, and public health. With the improvement of living standard, people have higher and higher requirements on keeping clean textiles (sports clothes, underwear, bedding and the like). Antimicrobial finishing has become an important choice for medical, surgical and public health due to the prevention of potentially pathogenic microorganisms present in hospital environments and the blocking of cross-infectious diseases. The types of microorganisms include: viruses, bacteria, unicellular animals and plants, certain algae and fungi, and the like. The classification of bacteria is mainly: gram positive, gram negative, spore or non-spore type. Some bacteria are pathogenic and can cause infections through the human blood brain barrier. A microorganism (such as bacteria and fungi) is generally protected by an outer cell wall composed of polysaccharides. The cell wall maintains the stability of cellular components, protecting the cell from the extracellular environment; below the cell wall is a semi-permeable membrane, inside which are organelles, enzymes and nucleic acids. Chemical reactions within the cell wall are caused by enzymes present within the cell wall. These nucleic acids contain the genetic information of the organism. Harmful microorganisms are generally present in the environment; in addition, the formation of substrates and chemical processes can promote the growth of microorganisms; further, moist and warm environments can exacerbate this phenomenon. Gram-positive bacteria contain peptidoglycan and teichoic acid, peptidoglycan consists of amino acids and sugars, accounting for 90% of the cell wall. Staphylococcus aureus is one of the representative strains of gram-positive bacteria, and has a size of 0.5-1.0 μm and a growth temperature range of 35-40 deg.C.

Staphylococcus aureus is the leading cause of cross-infection in hospital settings, accounting for 19% of the total surgical infections. It can also lead to furuncles and skin infections. Other gram-positive bacteria include staphylococcus epidermidis, streptococcus pneumoniae, streptococcus pyogenes and viral streptococci. Gram-negative bacteria are similar to gram-positive bacteria except that the outer layer of the cell membrane is attached to peptidoglycan by lipoproteins, which are used to transport lower molecular weight substances. One of the representative species of gram-negative bacteria is Escherichia coli; it is similar to bacillus in shape and parasitized in human intestinal tract. Coli can proliferate when raw food is consumed. Coli infections are characterized mainly by severe diarrhea (especially in children) and kidney damage. Such bacteria also include Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Salmonella enteritidis, Haemophilus influenzae, and the like. Infections caused by microorganisms are formed on fabrics, which are in direct contact with the body, by diseases caused by pathogens and odors. Furthermore, discoloration, coloration and loss of functional properties of textiles are the result of microbial destruction. The damage of fungi, moths and moulds to the fabric is relatively slow; can reach the fabric substrate and destroy the functional properties of the fabric. Algae, typically microorganisms, whether fungi or bacteria, produce a deep stain on the surface of the fabric. Dust mites are distributed in household textiles such as bedding (blankets, sheets, pillows), mattresses, carpets and the like, feed on human skin, and can cause allergic reactions by decomposing human waste (such as sweat, hair and the like).

The antimicrobial finishing process imparts to the textile substrate the ability to at least inhibit the growth or reproduction of certain types of microorganisms, or at least kill certain types of microorganisms. The antimicrobial finish can kill microorganisms by disrupting cell walls or altering the permeability of cell membranes, blocking the synthesis of microbial proteins, and blocking the production of enzymes necessary for microbial food. Some of the widely used antimicrobial finishes, such as silver, Quaternary Ammonium Compounds (QAC), haloamines, triclosan, and polyhexamethylene biguanide (PHMB), are almost all biocides.

Depending on the antibacterial mechanism of the fabric surface, three types of finishing can be roughly classified: controlled release, regeneration and barrier. The problem with the controlled release mechanism is the durability of the antimicrobial agent in the fabric that is in contact with the wearer's skin after washing and leaching. These drugs may cause irritation to the skin, resulting in serious allergy problems. These problems may also occur in fabrics finished using a recycling mechanism, since these ingredients require chlorine bleach to activate their antibacterial properties after washing. Chlorine-containing bleaches are not only harmful to cotton fabrics, but also harmful to human skin. While the barrier-blocking mechanism does not cause the problems associated with the other two approaches. The agents are attached to the surface of the fabric and are not easily leached out, thereby achieving the effect of killing bacteria contacting with the fabric.

The antibacterial finishing can be realized by physical and chemical methods and by adding functional agents on the textile fibers. There are two main types of such functional aids, namely, effective antimicrobial finishes and durable antimicrobial finishes. Because the finish is weakly bound to the fiber surface, the instant antimicrobial finish is susceptible to failure during contact with skin or body fluids or during laundering. Durable antimicrobial finishes are typically achieved by adding the antimicrobial finish to wet-processed fibers or textiles, which is the controlled release mechanism mentioned above. In such treatments, the finish itself may be used in conjunction with the fiber surface or the bonding substance. The treated textile inactivates bacteria by slowly releasing the antimicrobial agent from the fiber or fabric surface.

Specifically, CN102505467A discloses a finishing liquid for fabric antibiosis and a preparation method thereof, wherein the finishing liquid is composed of the following raw materials in parts by weight: 0.1 part of chitosan; DC-57000.5 parts; 0.2 part of nano-silver antibacterial agent; 1 part of 3-chloropropylmethyldimethoxysilane; 0.3 part of 2, 4, 4' -trichloro-2-hydroxy-diphenyl ether; 3 parts of PEG-40 hydrogenated castor oil; 0.3 part of water-soluble lanolin; 10 parts of ethanol; 84.6 parts of RO water. Although it employs chitosan having an antibacterial effect including a more effective antibacterial agent, the silicone quaternary antibacterial compound may cause skin allergy. The disclosed method, however, shows that it does not contain isolated antimicrobial-releasing units, resulting in poor wash durability, although it may have some antimicrobial activity.

CN100336968C discloses a method for obtaining antifungal, candida and antibacterial textile products. The object of the invention is to obtain an antimicrobial product capable of reducing infectious diseases transmitted or spread by textile products, reducing the extra cost and effort spent to ensure hygiene, and increasing the hygiene of disposable textile products. A solution of triclosan, chlorhexidine, and disodium octaborate pentahydrate is used in the method of the invention. The solution is capable of converting a hydrophobic textile product into a hydrophilic product, thereby enabling the antimicrobial agent in the solution to be incorporated into the textile product. But the antibacterial component easily loses antibacterial activity due to water solubility thereof, which is easily lost with the washing of the fabric.

Disclosure of Invention

In view of the shortcomings of the prior art, the invention aims to provide an antimicrobial composite microsphere and a preparation method and application thereof.

The technical scheme adopted by the invention is as follows:

the invention provides a composite microsphere, which is provided with a shell layer formed by cross-linked polysaccharide, wherein an active ingredient is loaded in the shell layer, and the surface of the shell layer is modified with a metal ingredient.

The invention further provides a surface charge-rich composite microsphere, which comprises a shell layer formed by cross-linked polysaccharide, wherein active ingredients are loaded in the shell layer, the surface of the shell layer is modified with metal ingredients, and the shell layer also comprises a charge-rich film, wherein the charge-rich film is obtained by self-assembling polyelectrolyte layer by layer.

In the technical scheme of the invention, the active ingredient is selected from one or more of antimicrobial agent, fragrant substance and fabric conditioning substance. Preferably, the active ingredient comprises at least an antimicrobial agent.

In the technical scheme of the invention, the active ingredient is preferably an oil-soluble ingredient, or at least comprises one oil-soluble ingredient or is an active ingredient-containing liquid dispersed in an oil-soluble liquid.

Preferably, the antimicrobial agent is selected from the group consisting of organic antimicrobial agents, inorganic antimicrobial agents, natural antimicrobial agents.

In some preferred embodiments, the antimicrobial agent is a natural antimicrobial agent. In the present invention, the natural antimicrobial agent refers to a mixture obtained by extraction from natural animals and plants, which has an effect against pathogenic microorganisms including bacteria, viruses, fungi, spirochetes, mycoplasma, rickettsia, chlamydia, prions, parasites, and the like.

In some preferred embodiments, the natural antimicrobial agent includes, but is not limited to, natural plant extracts, more preferably neem extracts, ginkgo biloba extracts, papaya extracts, pineapple extracts, aloe extracts, rosemary extracts, orange flower extracts, clove extracts, eclipta alba extracts, lindera aggregata extracts, mint extracts, lawsonia extracts, walnut extracts, violaxantha extracts, curcumin, pomegranate extracts, onion extracts, violet extracts.

In some preferred embodiments, the inorganic antimicrobial agent is selected from silver or silver salts, silica alumina.

In the technical scheme of the invention, the metal component is selected from metal salt, metal oxide or metal nano-particles;

preferably, the metal salt is selected from one or more of silver salt, zinc salt and copper salt.

Preferably, the metal oxide is selected from one or more of copper oxide, zinc oxide, titanium oxide, magnesium oxide, silver oxide, gold oxide and calcium oxide.

Preferably, the nanoparticles of metal are selected from the group consisting of copper oxide nanoparticles, zinc oxide nanoparticles, titanium oxide nanoparticles, magnesium oxide nanoparticles, silver oxide nanoparticles, gold oxide nanoparticles, copper nanoparticles, zinc nanoparticles, titanium nanoparticles, magnesium nanoparticles, silver nanoparticles, gold nanoparticles.

In the technical scheme of the invention, the cross-linked polysaccharide is selected from any one or a combination of at least two of cross-linked natural linear polysaccharide and derivatives and analogues thereof; preferably the cross-linked natural linear polysaccharide is selected from cross-linked chitosan, cross-linked sodium alginate, cross-linked gum arabic, cross-linked gelatin, cross-linked cellulose.

In the technical scheme of the invention, the composite microspheres are obtained by the following method, which comprises the following steps:

1) mixing active ingredient, surfactant and non-crosslinked polysaccharide ingredient to form oil-in-water emulsion, and adding the oil-in-water emulsion into the second oil phase to form oil-in-water (o/w/o) emulsion,

2) crosslinking and solidifying the polysaccharide component in the emulsion obtained in the step 1) by a chemical method or a physical method to form microspheres containing the active ingredient and having a crosslinked polysaccharide shell, and separating the microspheres containing the active ingredient and having the crosslinked polysaccharide shell from the second oil phase;

3) compounding the microspheres obtained in the step 2) with metal components to obtain the composite microspheres with the metal components modified on the surfaces.

In the technical scheme of the invention, the surface charge-rich composite microsphere is obtained by the following method, which comprises the following steps:

3) compounding the microspheres obtained in the step 2) with metal components to obtain composite microspheres with metal components modified on the surfaces;

4) mixing the composite microspheres for the fabric obtained in the step 3) with polyelectrolyte for reaction, and repeatedly reacting with the polyelectrolyte for N times after separation to obtain the surface charge-rich composite microspheres with the surface formed with the charge-rich membrane.

In another aspect, the present invention provides a method for preparing the composite microsphere of the present invention, which comprises the following steps:

In another aspect, the present invention provides a method for preparing the surface charge-rich composite microsphere, which comprises the following steps:

4) mixing the composite microspheres for the fabric obtained in the step 3) with polyelectrolyte for reaction, and repeatedly reacting with the polyelectrolyte for N times after separation to obtain the surface charge-rich composite microspheres for the fabric with the surface charge-rich membrane.

In the technical scheme of the invention, the non-crosslinked polysaccharide component in the step 1) is selected from chitosan, sodium alginate, acacia, gelatin, cellulose, hyaluronic acid, glucose, pectin, collagen, alginic acid, starch, dextrin and derivatives thereof.

In the technical scheme of the invention, the chemical method in the step 2) is to add a cross-linking agent to perform cross-linking reaction on the non-cross-linked polysaccharide component, wherein the cross-linking agent is selected from sodium tripolyphosphate, calcium salt, aldehydes, phosphorus oxychloride, sodium trimetaphosphate, acetic acid and adipic acid.

In some embodiments of the invention, the non-crosslinked polysaccharide component of step 1) is selected from chitosan; the cross-linking agent in the step 2) is selected from sodium tripolyphosphate.

In some embodiments of the invention, the non-crosslinked polysaccharide component of step 1) is selected from sodium alginate; the cross-linking agent in step 2) is selected from calcium chloride.

In some embodiments of the invention, the surfactant described in step 1) is selected from the group consisting of tween, span, polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer.

In the technical scheme of the invention, the second oil phase is oil-soluble liquid immiscible with water, preferably kerosene, paraffin oil and petroleum ether

In the technical scheme of the invention, the physical method in the step 2) is ultraviolet irradiation or repeated freeze thawing.

In the technical scheme of the invention, the method for compounding the microspheres and the metal components in the step 3) comprises one or more of electrostatic adsorption, ionic adsorption and covalent bonding.

In the technical scheme of the invention, the polyelectrolyte is an anionic polyelectrolyte, a cationic polyelectrolyte or an inorganic polyelectrolyte, preferably, the anionic polyelectrolyte is selected from sodium polystyrene sulfonate, polyacrylic acid, polymethacrylic acid, polystyrene sulfonic acid, polyvinyl sulfonic acid and polyvinyl phosphoric acid, and preferably, the cationic polyelectrolyte is selected from polyethyleneimine, polyvinylamine and polyvinyl pyridine. Preferably, the inorganic polyelectrolyte is polyphosphate or polysilicate.

In a further aspect of the present invention there is provided a fabric care composition comprising the above composite microspheres or surface-charge-rich composite microspheres.

In one embodiment of the present invention, the fabric care composition is selected from the group consisting of fabric softening compositions, fabric enhancing compositions, fabric cleaning compositions, fabric finishing compositions, and combinations thereof. Such compositions are in the form of liquids, gels, beads, powders, flakes and granules.

In a further aspect of the present invention there is provided a method of treating a fabric comprising the step of applying to the fabric the above-described composite microspheres or surface charge-rich composite microspheres or a fabric care composition.

In a further aspect of the present invention there is provided a method of imparting antimicrobial activity to a fabric, the method comprising the step of applying to the fabric a composite microsphere or surface charge-rich composite microsphere as described above or a fabric care composition.

In a further aspect, the present invention provides the use of an antimicrobial composite microsphere for textile finishing as described above in an antimicrobial setting.

Compared with the prior art, the invention has the following beneficial effects:

the invention creatively combines polysaccharide substances, active ingredients, especially active ingredients of natural antibacterial ingredients, with metal ingredients, exerts the synergistic advantage and obviously enhances the antimicrobial effect of the fabric.

According to the invention, a layer-by-layer self-assembly method is adopted, and the polyelectrolytes are superposed layer by layer to form the charge-rich film, so that the surface of the composite microsphere is charged with static electricity, and meanwhile, the formed charge-rich film protects the metal component modified on the surface of the shell from falling off easily. According to the invention, the surface of the fabric comprises the film rich in charges, so that the fabric can be more firmly adsorbed on the surface of the fabric through electrostatic action, and the composite microspheres can still remain on the surface of the fabric after 30 times and 50 times of washing.

The invention uses the microsphere form to package the antibacterial substance, and the microsphere can keep a stable state in the water environment, so that the composite microsphere can be added into compositions for cleaning fabrics and the like, and can keep a stable state in the cleaning process, thereby ensuring that more composite microspheres are remained on the surface of the fabrics and act for a long time, and achieving the purpose of resisting microorganisms for a long time.

In conclusion, the invention has excellent washing resistance and wide application range, and can be used for antimicrobial after-finishing of different fabrics; and has good biocompatibility.

Specifically, the adsorption modification, slow release performance and washing fastness effect formed by the material are achieved by the following modes: the antimicrobial composite microspheres are modified in the fabric in an electrostatic adsorption manner; the natural antimicrobial agent wrapped in the composite microspheres is slowly released at a certain speed to kill microorganisms; the antimicrobial composite microspheres are tightly combined with the fabric, and the fabric can still keep the antimicrobial effect after being washed for many times. The antimicrobial composite microspheres for fabric after-finishing of the present invention provide a strategy for fabric antimicrobial after-finishing.

Drawings

FIG. 1 is a scanning electron microscope photograph of the composite microsphere of the embodiment of the present invention after preparation.

FIG. 2 is a scanning electron micrograph of the composite microspheres of the example of the present invention after 7 days of preparation (storage in pure water).

FIG. 3 is a comparison of fibers of a fabric according to an embodiment of the present invention. Wherein the left image is without treatment and the right image is after treatment.

FIG. 4 is a graph of the results of an antimicrobial composite microsphere "antibacterial ring" experiment in an example of the present invention. Wherein, the left picture is a culture dish inoculated with escherichia coli, and the right picture is a culture dish inoculated with staphylococcus aureus; point a is a blank control, point b is a PPS control, and point c is a composite microsphere group.

FIG. 5 is a scanning electron micrograph of the fabric fibers after 30 and 50 washes in accordance with an embodiment of the present invention.

Detailed Description

The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

In some embodiments, the active ingredient is selected from the group consisting of an antimicrobial agent, a fragrance material, a fabric conditioning material, and combinations of one or more thereof. In some preferred embodiments, the active ingredient includes at least an antimicrobial agent.

In some embodiments, the active ingredient is preferably an oil-soluble ingredient, or at least comprises an oil-soluble ingredient or is an active ingredient-containing liquid dispersed in an oil-soluble liquid.

In some preferred embodiments, the antimicrobial agent is selected from the group consisting of organic antimicrobial agents, inorganic antimicrobial agents, natural antimicrobial agents.

In some preferred embodiments, the natural antimicrobial agent includes, but is not limited to, natural plant extracts, more preferably neem extracts, ginkgo biloba extracts, papaya extracts, pineapple extracts, aloe extracts, rosemary extracts, orange flower extracts, clove extracts, eclipta alba extracts, lindera aggregata extracts, mint extracts, lawsonia extracts, walnut extracts, violaxanthus extracts, curcumin, pomegranate extracts, onion extracts, violet extracts.

In some preferred embodiments, the organic antimicrobial agent is selected from the group consisting of Quaternary Ammonium Compounds (QACs), n-halamines, polyhexamethylene biguanide; triclosan, a silicon-based quaternary agent; iodine, phenol, thiophenol, heterocyclic compounds, inorganic salts, nitro compounds, urea, amines, formaldehyde derivatives.

QACs have antibacterial performance on wool, cellulose-based cotton, synthetic polyamide and polyester, the MIC value is 10-100mg/l, the reproducibility is good, and the washability is good. QACs can block the synthesis of microbial proteins, by killing the microorganisms by altering the permeability of the cell membrane, and prevent the production of enzymes required by the microorganisms to digest food. The n-halamine compound is activated by a chlorine-containing bleaching agent, and antibacterial property is given to the cotton fabric in the process of rolling dry and curing. The sample after chlorination shows potential antibacterial capability to gram-positive and gram-negative pathogenic bacteria. Experiments show that after chlorination for 15 days, the available chlorine can be recovered to 85 percent, and the n-halamine compound can ensure that the fabric has good biological killing effect. The other organic antibacterial agent triclosan mainly has the function of improving the antibacterial capacity of polyester, nylon, regenerated cellulose and acrylic fiber; MIC values for bacteria may be below 10 ppm. Triclosan inhibits the growth of microorganisms by inhibiting lipid synthesis, and has good durability. Polyhexamethylene biguanide (PHMB) is widely applied to the industries of medical care, pharmacy, food and the like, is an organic antibacterial agent with high acceptance, and is effective on gram-negative bacteria, gram-positive bacteria, yeast, fungi and the like. PHMB is slightly toxic, but there are few reports of skin infections. PHMB can be used in a variety of products, including underwear and terry towels, to deter microbial growth and exhibit good wash durability. PHMB shows bacteriostasis at 1-10mg/l, but the bactericidal activity and the bacteriostasis rate of PHMB are increased together when the concentration is increased. According to the existing data, when the pH value is between 5 and 6, the PHMB can achieve the maximum bacteriostatic action.

In some preferred embodiments, the inorganic antimicrobial agent is selected from silver or silver salts, silica to alumina ratio.

In some preferred embodiments, the metal component is selected from a metal salt, a metal oxide, or a metal nanoparticle;

preferably, the metal salt is selected from silver nitrate, silver chloride, zinc chloride.

In some preferred embodiments, the cross-linked polysaccharide is selected from any one or a combination of at least two of cross-linked natural linear polysaccharides and derivatives and analogues thereof; preferably the cross-linked natural linear polysaccharide is selected from cross-linked chitosan, cross-linked sodium alginate, cross-linked gum arabic, cross-linked gelatin, cross-linked cellulose.

In some preferred embodiments, the composite microspheres are obtained by a method comprising the steps of:

In some preferred embodiments, the surface charge-rich composite microspheres are obtained by a method comprising the steps of:

In some preferred embodiments, the non-crosslinked polysaccharide component of step 1) is selected from the group consisting of chitosan, sodium alginate, gum arabic, gelatin, cellulose, hyaluronic acid, glucose, pectin, collagen, alginic acid, starch, dextrin, and derivatives thereof.

In some preferred embodiments, the chemical method in step 2) is to add a cross-linking agent selected from the group consisting of sodium tripolyphosphate, calcium salts, aldehydes, phosphorus oxychloride, sodium trimetaphosphate, acetic acid, adipic acid to perform a cross-linking reaction on the uncrosslinked polysaccharide component; preferably, the calcium salt is selected from calcium chloride.

In some preferred embodiments, the non-crosslinked polysaccharide component of step 1) is selected from chitosan; the cross-linking agent in the step 2) is selected from sodium tripolyphosphate.

In some preferred embodiments, the non-crosslinked polysaccharide component of step 1) is selected from sodium alginate; the cross-linking agent in step 2) is selected from calcium chloride.

In some preferred embodiments, the surfactant described in step 1) is selected from the group consisting of tween, span, polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer. Such as any one or the combination of at least two of Tween 20, Tween 80, span 60, span 80, polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer, Pluronic series, etc.

In some preferred embodiments, the second oil phase is a water-immiscible oil-soluble liquid, preferably kerosene, paraffin oil, petroleum ether

In some preferred embodiments, the physical method in step 2) is ultraviolet irradiation or repeated freeze-thaw.

In some preferred embodiments, the method of complexing the microsphere with the metal component in step 3) comprises a combination of one or more of electrostatic adsorption, ionic adsorption, and covalent bonding.

In some preferred embodiments, the method of forming the composite microspheres includes magnetic stirring, ultrasonic dispersion, mechanical shearing, and the like.

In some preferred embodiments, the polyelectrolyte is an anionic polyelectrolyte or a cationic polyelectrolyte, preferably, the anionic polyelectrolyte is selected from sodium polystyrene sulfonate, polyacrylic acid, polymethacrylic acid, polystyrene sulfonic acid, polyvinyl phosphoric acid;

preferably, the cationic polyelectrolyte is selected from the group consisting of polyethyleneimine, polyvinylamine, polyvinylpyridine.

Preferably, the inorganic polyelectrolyte is polyphosphate or polysilicate.

In some preferred embodiments, the fabric care composition is selected from the group consisting of fabric softening compositions, fabric enhancing compositions, fabric cleaning compositions, fabric after-finishing compositions, and combinations thereof. Such compositions are in the form of liquids, gels, beads, powders, flakes and granules.

Preferably, the antimicrobial scenes comprise scenes such as personal hygiene (such as the situations that sports clothes, coats and the like are in more contact with the outside, the washing intervals are longer, or body fluids such as sweat are often soaked), occupational hygiene (such as the situations that sanitation workers work clothes, medical protective clothing and the like have specific antimicrobial requirements), environmental hygiene (such as the situations that decorative fabrics, isolation bins and the like need to keep the surfaces of fabrics clean), and the like.

The inorganic antibacterial agent mainly comprises metal oxide, copper, zinc, titanium, magnesium, silver, gold and the like.

In some embodiments, the antimicrobial agent has a MIC value for Escherichia coli of 0.05-0.1mg/l on cellulose, protein, recycled materials, and synthetic materials, and has better wash durability.

In the present invention, the term "extract" is a component of natural materials obtained by an extraction process for any part of animals or plants, which may be a single ingredient or a mixture. Extracts include, but are not limited to, aqueous extracts, non-aqueous extracts, alcoholic extracts, concentrates, oils, impregnates, powders, granules, and combinations of two or more thereof.

In general, the antimicrobial properties of any inorganic finish are determined by its chemical composition. The microbiocidal efficiency of inorganic agents will slowly decline during use and washing. Most of these agents have limited microbial inhibitory potency, are toxic, can cause irritation to the skin of the human body, and can be potentially harmful during metabolism or decomposition. To reduce the risks associated with the use of such inorganic formulations, antimicrobial treatment of textiles requires a large number of alternative formulations. As previously mentioned, there are many organic antimicrobial agents available for textile treatment, but all are limited to triclosan, quaternary ammonium compounds, polyhexamethylene biguanide, and the like, which have found industrial application. Polyhexamethylene biguanide has certain environmental toxicity and is not easy to decompose in natural environment. The U.S. environmental protection agency (US-EPA) regulates PHMB to the extent that wastewater containing PHMB is not permitted to be discharged without the associated mandated treatment.

Compared with the traditional inorganic and organic medicaments, the polysaccharide composite microspheres which are modified with metal components on the surfaces and coated with natural antimicrobial agents have the characteristics of high-efficiency antibiosis, washing resistance, durability and mild and non-toxicity, and the problem that the existing medicament cannot solve the problems of both performance and safety is solved: 1) the antimicrobial composite microspheres with the surfaces modified by different types of metal ions with different concentration combinations have the advantages that the metal ions can destroy the membrane function of cells while the microorganisms enrich the metal ions, so that intracellular components overflow, the effect of interfering cell metabolism or interfering intracellular enzyme activity is achieved, the biological function of the cells is lost, the cells are finally killed, and the effect of high-efficiency antibiosis is achieved; 2) the composite microsphere structure synthesized by natural antimicrobial agents with different concentrations and polysaccharide substances with different types and different concentration ratios can be firmly attached to fabric fibers and simultaneously adjust the escape rate of the natural antimicrobial agents, thereby achieving the effect of washing resistance and durability; 3) the related polysaccharide substances, natural antimicrobial agents, metal ions and the like are raw materials with high biocompatibility, and the effect of 'mildness and no toxicity' of the finished fabric can be realized.

In some embodiments, the composite microspheres have a particle size of 1-100 μm, such as 1 μm, 5 μm, 10 μm, 20 μm, 40 μm, 60 μm, 80 μm, 100 μm, and the like. The particle size of the composite microspheres is selected to be within the range of 1-100 mu m, because the particle size of the composite microspheres exceeding the range can cause the particle size of the composite microspheres to be larger than the diameter of the plant fibers, the attachment and the stability of the microspheres are not easy to occur, and the particle size of the composite microspheres falling below the range can cause the content of the natural antimicrobial agent to be too small, and the antimicrobial efficiency is reduced.

In some embodiments, the polysaccharide material comprises a homogeneous polysaccharide and a heterogeneous polysaccharide;

in some preferred embodiments, the metal component includes any one or a combination of at least two of metal ions having antibacterial and antiviral effects, such as copper ions, zinc ions, or silver ions;

in some preferred embodiments, the natural antimicrobial agent requires a pretreatment, which is a miscible filtration method.

The mixing and filtering method is to filter the natural plant extract; and taking the filtrate, standing, adding a stabilizer, standing again, filtering to obtain the filtrate, and standing again to obtain the natural antimicrobial agent.

In some preferred embodiments, the stabilizer is a biocompatible antioxidant. Such as hydrogen peroxide and percarbonate.

Specifically, the adsorption modification, slow release performance and washing fastness effects formed by the composite microspheres are achieved by the following modes:

the composite microspheres with rich charges on the surface are modified in the fabric in an electrostatic adsorption manner; the natural antimicrobial agent wrapped in the composite microspheres is slowly released at a certain speed to kill microorganisms; the antimicrobial composite microspheres are tightly combined with the fabric, and the fabric can still keep the antimicrobial effect after being washed for many times.

In the specific embodiment of the invention, the fabric comprises any product prepared from the fabric, such as life clothes (such as sports clothes, coats and the like which are in more contact with the outside, have longer washing intervals or are often soaked in body fluid such as sweat and the like), professional clothes (such as sanitation worker work clothes, medical protective clothes and the like which have specific antimicrobial requirements), environmental sanitation (such as decorative fabrics, isolation cabins and the like which need to keep the surface of the fabric clean) and the like.

Example 1 preparation example

The present example provides an antimicrobial composite microsphere. The antimicrobial composite microsphere is a polysaccharide composite microsphere which is modified with metal components on the surface and is coated with a natural antimicrobial agent. The preparation method comprises the following steps:

(1) filtering 3mL of chinaberry leaf extract in a dark environment; standing for 1 h; then 100 mu L of hydrogen peroxide is dissolved and dispersed in the solution; filtering the solution; standing for 1 h; obtaining purified and stabilized neem leaf extract;

(2) wrapping the solution obtained in the step (1) in an oil-in-water (o/w) emulsification structure formed by 1.0% (w/v) Tween 20 and 2.0% (w/v) sodium alginate aqueous solution; then slowly dripping the obtained oil-in-water (o/w) emulsified structure into paraffin oil in a stirring state to form an oil-in-water (o/w/o) structure, and crosslinking and solidifying sodium alginate in a water layer by using 1.0% (w/v) calcium chloride solution; washing with DDI water for several times, and separating and purifying the cured microspheres from the second oil layer; obtaining sodium alginate-chinaberry leaf extract composite microspheres;

(3) and (3) dripping a zinc chloride solution with the concentration of 0.1mol/L under the stirring state, and continuously stirring for 12 hours to obtain the antimicrobial composite microspheres.

Example 2 preparation example

(1) filtering 2mL of rosemary extract in a dark environment; standing for 1 h; then 50mg of sodium percarbonate is dissolved and dispersed in the sodium percarbonate; filtering the solution; standing for 1 h; obtaining a purified and stabilized rosemary extract;

(2) dispersing and wrapping 10mL of the solution obtained in the step (1) in an oil-in-water (o/w) emulsifying structure formed by 2.0% (w/v) polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer (P123) and 2.0% (w/v) chitosan solution (0.1M acetic acid, the concentration of chitosan is 2.5g/L, and the pH value is adjusted to 5 by 1% NaOH) by a high-speed disperser at 8000 rpm/min; then slowly dripping the obtained oil-in-water (o/w) emulsified structure into petroleum ether under stirring to form an oil-in-water (o/w/o) structure, and adding a 0.5% (w/v) sodium tripolyphosphate solution into the solution under magnetic stirring at room temperature; then washing the second oil layer with DDI water for several times to separate and purify the solidified microspheres; obtaining chitosan-rosemary extract composite microspheres;

(3) under the stirring state, a silver nitrate solution with the concentration of 0.05mol/L is dripped in, and the stirring is continued for 8 hours to obtain the antimicrobial composite microsphere. After the reaction, the sample was collected by low speed centrifugation and washed several times with DDI water to remove the non-attached silver ions.

Example 3 stability in Water assay

This example uses a scanning electron microscope to observe the morphological characteristics of the antimicrobial composite microspheres prepared in example 1. As shown in FIG. 1; the prepared antimicrobial composite microspheres were dissolved in ultrapure water, and the morphology thereof was observed after 7 days, with the results shown in fig. 2. According to the results, the composite microspheres did not change much in morphology over a period of time. Indicating that the catalyst can exist stably in water and can be applied to the addition of a washing process.

Example 4 layer-by-layer self-assembly preparation of surface-charge-rich composite microspheres

This example describes the use of antimicrobial composite microspheres prepared according to the present invention. In the embodiment, the antimicrobial composite microspheres are arranged on cotton and wool fabrics mainly by a layer-by-layer electrostatic self-assembly technology, so that the antibacterial performance of the fabrics is improved.

Specifically, mixing a proper amount of composite microspheres with 15mL of 10g/L sodium polystyrene sulfonate (PPS) solution for reaction for 120s, centrifuging, dissolving the precipitate in deionized water, ultrasonically dispersing, and repeating the above processes for 5-20 times in sequence to obtain negatively charged composite microspheres with a certain size; soaking the wool fabric in hydrochloric acid solution with pH of 2 for 10-30min for later use; or soaking the cotton fabric in deionized water for 10-30 min; immersing the treated wool fabric with the positive surface charge into the composite microsphere solution with the negative surface charge, adsorbing the composite microspheres on the surface of the fabric in an electrostatic adsorption mode, drying in the air, and drying in an oven at 100 ℃. The scanning electron microscope observation result is shown in fig. 3, wherein the left side is the scanning electron microscope image of the surface of the fabric which is not treated, and the right side is the scanning electron microscope image of the surface of the fabric which is treated by the composite microspheres. According to the results, the composite microspheres are attached to the surface of the treated fabric fiber, and have an obvious hierarchical structure, but not the surface of the fabric fiber without treatment.

Example 5 antimicrobial Property testing

This example evaluates the antimicrobial properties of antimicrobial composite microspheres prepared according to the present invention. Namely, the composite microspheres are contacted with microorganisms with different concentrations, different types and the like for different time periods, and the antimicrobial capability of the composite microspheres is measured.

The specific operation is as follows: to a tryptone soy agar plate, 100. mu.L of a medium containing a certain concentration of bacteria was dropped, followed by development to uniformly distribute the microorganisms on the agar. The agar was punched out, and 100. mu.L of antimicrobial composite microspheres (experimental group, sample was composite microspheres prepared in example 4), sodium polystyrene sulfonate solution (negative control group), and PBS group (blank control group) were added, respectively. The inoculated tryptone soy agar plates were then transferred to an incubator at 37 ℃ for 24 h. The zone of inhibition where the microorganism does not grow is measured. The size of the zone of inhibition represents the antibacterial effect. The "high-efficiency antibacterial" performance of the antimicrobial composite microspheres was evaluated by the "antibacterial ring" test. The results are shown in FIG. 4, where the left panel is a dish inoculated with E.coli and the right panel is a dish inoculated with S.aureus, where point a is a blank control and point b is a blank control. According to the results, the composite microspheres have obvious inhibition performance on escherichia coli and staphylococcus aureus, the antimicrobial composite microsphere group has wider antibacterial rings (the radius of the antibacterial ring in escherichia coli is 0.58 +/-0.07, and the radius of the antibacterial ring in staphylococcus aureus is 0.52 +/-0.08), and the antibacterial rings are not generated in the PBS group and the sodium polystyrene sulfonate solution group.

Example 6 measurement of washing resistance

This example evaluates the wash durability properties of antimicrobial composite microspheres prepared according to the present invention. The composite microspheres are attached to the surface of the fabric through after-treatment, the remaining amount of the composite microspheres is measured after different times of washing, and the durability of the antimicrobial function of the composite microspheres is evaluated.

The specific operation is as follows: the evaluation of the fastness to washing and the persistence of the antimicrobial function is referred to GB/T3921.3-1997 colour fastness to washing in the textile colour fastness test: test 3 ", the finished fabric was washed using the following conditions: bath ratio of 1: 30, 2g/L of soap solution (standard soap flakes) (40 +/-2) DEG C, and washing for 2 min. The fabric is washed for 30 times and 50 times respectively, and the 'washing endurance' performance of the fabric is evaluated by testing the retention amount of the composite microspheres and the change of the antibacterial rate of the fabric after different washing times.

The fabric impregnated with the negatively charged composite microspheres prepared in example 4 was evaluated, and the fabric washed 30 times and 50 times was examined by scanning electron microscopy, respectively, and the results are shown in fig. 5, wherein the left image is the fabric fiber washed 30 times, and the right image is the fabric fiber washed 50 times. According to the attached drawing, after 30 times of washing, the composite microspheres can still be obviously observed on the fabric fibers; after 50 times of washing, a certain amount of microspheres still remain on the fabric fibers. The experimental result proves that the product of the invention has good washing fastness which can reach more than 50 times.

The applicant states that the present invention is illustrated by the above examples to show the materials, preparation methods and applications of the antimicrobial composite microspheres of the present invention, but the present invention is not limited to the above examples, i.e. it does not mean that the present invention must be implemented by the above examples. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

Claims

1. A composite microsphere, the composite microsphere has a shell layer formed by cross-linked polysaccharide, an active ingredient is encapsulated in the shell layer, and the surface of the shell layer is modified with a metal component.

2. a surface-rich composite microsphere, the surface-rich composite microsphere has a shell layer formed by cross-linked polysaccharide, the shell layer is loaded with active components, the surface of the shell layer is decorated with metal components, and the shell layer also includes Charge-rich membranes obtained by layer-by-layer self-assembly of polyelectrolytes.

3. The composite microsphere according to claim 1, or the surface charge-rich composite microsphere according to claim 2, wherein the active ingredient is selected from one or more of antimicrobial agents, fragrance substances, and fabric conditioning substances Preferably, the active ingredient includes at least an antimicrobial agent; more preferably, the active ingredient is preferably an oil-soluble ingredient, or at least one oil-soluble ingredient, or an active ingredient-containing liquid dispersed in an oil-soluble liquid.

4. The composite microsphere according to claim 3 or the surface-charged composite microsphere, wherein the antimicrobial agent is selected from organic antimicrobials, inorganic antimicrobials, and natural antimicrobials;

Preferred natural antimicrobial agents are natural plant extracts, more preferably neem extracts, ginkgo biloba extracts, papaya extracts, pineapple extracts, aloe vera extracts, rosemary extracts, orange blossom extracts, Clove Extract, Eclipta Root Extract, Cinnamon Horse Extract, Peppermint Extract, Astragalus Extract, Walnut Extract, Rhizoma Vermilion Extract, Curcumin, Pomegranate Extract, Onion Extract, Purple Mineral Extract thing;

Preferably, the inorganic antibacterial drug is selected from silver or silver salts, silicon aluminum;

Preferably, the organic antibacterial drug is selected from the group consisting of quaternary ammonium salt compounds, n-halamines, polyhexamethylene biguanide, triclosan, silicon-based quaternary agents, iodine, phenols, thiophenols, heterocyclic compounds, inorganic salts, nitrates base compounds, urea, amines, formaldehyde derivatives.

5. The composite microsphere according to claim 1, or the surface charge-rich composite microsphere according to claim 2, wherein the metal component is selected from metal salts, metal oxides or metal nanoparticles;

Preferably, the metal salt is selected from one or more combinations of silver nitrate, silver chloride, zinc chloride, titanium oxide, magnesium oxide, silver oxide, gold oxide, and calcium oxide,

Preferably, the metal oxide is selected from one or more combinations of copper oxide, zinc oxide, titanium oxide, magnesium oxide, silver oxide, gold oxide, and calcium oxide,

Preferably, the metal nanoparticles are selected from copper oxide nanoparticles, zinc oxide nanoparticles, titanium oxide nanoparticles, magnesium oxide nanoparticles, silver oxide nanoparticles, gold oxide nanoparticles, copper nanoparticles, zinc nanoparticles, titanium nanoparticles , magnesium nanoparticles, silver nanoparticles, gold nanoparticles.

6. The composite microsphere according to claim 1, or the surface charge-rich composite microsphere according to claim 2, wherein the cross-linked polysaccharide is selected from any of the cross-linked natural linear polysaccharides and derivatives and analogs thereof. One or a combination of at least two; preferably the cross-linked natural linear polysaccharide is selected from cross-linked chitosan, cross-linked sodium alginate, cross-linked gum arabic, cross-linked gelatin, cross-linked cellulose.

7. The surface charge-rich composite microspheres according to claim 2, wherein the polyelectrolyte is an anionic polyelectrolyte, a cationic polyelectrolyte or an inorganic polyelectrolyte,

Preferably, the anionic polyelectrolyte is selected from sodium polystyrene sulfonate, polyacrylic acid, polymethacrylic acid, polystyrene sulfonic acid, polyvinylsulfonic acid, polyvinylphosphoric acid,

Preferably, the cationic polyelectrolyte is selected from polyethyleneimine, polyethyleneamine, polyvinylpyridine;

Preferably, the inorganic polyelectrolytes are selected from polyphosphates and polysilicates.

8. A fabric care composition comprising the composite microspheres of any one of claims 1,3-6 or the surface-rich composite microspheres of any one of claims 2-7 in the fabric care composition ;

Preferably, the fabric care composition is selected from the group consisting of fabric softening compositions, fabric enhancing compositions, fabric cleaning compositions, fabric finishing compositions, and combinations thereof.

9. A method for treating fabric, the method comprising applying the composite microspheres of any one of claims 1, 3-6 or the surface-rich composite microspheres of any one of claims 2-7 or the The step of applying the fabric care composition of claim 8 to a fabric.

10. A method of imparting antimicrobial activity to a fabric, the method comprising mixing the composite microspheres of any one of claims 1, 3-6 or the surface-charged composite microspheres of any one of claims 2-7. The step of applying the ball or the fabric care composition of claim 8 to a fabric.

11. the preparation method of the composite microsphere described in any one of claim 1,3-6, it comprises the steps:

1) form an oil-in-water emulsion by mixing active ingredients, surfactants and uncrosslinked polysaccharide components, then in the second oil phase of the oil-in-water emulsion, form an emulsion of an oil-in-water-in-oil emulsification structure,

2) The polysaccharide component in the emulsion obtained in step 1) is cross-linked and solidified by a chemical method or a physical method to form a microsphere containing an active component and a cross-linked polysaccharide shell, and the microsphere containing the active component and having a cross-linked polysaccharide shell is removed from the separation in the second oil phase;

3) compounding the microspheres obtained in step 2) with metal components to obtain composite microspheres whose surfaces are decorated with metal components;

Preferably, the uncrosslinked polysaccharide component in step 1) is selected from chitosan, sodium alginate, gum arabic, gelatin, cellulose, hyaluronic acid, glucose, colloid, xanthocollagen, alginic acid, starch, dextrin and its derivatives;

Preferably, the chemical method in step 2) is to add a cross-linking agent to make the uncross-linked polysaccharide components undergo a cross-linking reaction, and the cross-linking agent is selected from sodium tripolyphosphate, calcium salts, aldehydes, calcium chloride, Phosphorus oxychloride, sodium trimetaphosphate, acetic acid, adipic acid;

Preferably, the surfactant described in step 1) is selected from Tween, Span, polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer;

Preferably, the second oil phase is an oil-soluble liquid immiscible with water.

12. the preparation method of the described surface charge-rich composite microsphere of any one of claim 2-7, it comprises the steps:

4) mixing and reacting the composite microspheres for fabrics obtained in step 3) with the polyelectrolyte, and repeating the reaction with the polyelectrolyte for N times after separation to obtain the surface charge-rich composite microspheres for fabrics with a charge-rich film formed on the surface;