Technical Field:

The invention relates to the application of eucalyptus essential oil to microcapsules with antibacterial properties and textile materials, which are widely used in many industries such as food, agriculture, medicine, pharmaceuticals, and cosmetics. Although the textile industry started its studies in this field late compared to other sectors, it is currently producing innovative ideas and inventions in this field.

When microcapsules with antibacterial properties containing eucalyptus essential oil are applied to textile surfaces, they are used both on textile surfaces used in our daily lives and on all kinds of textile surfaces used in the health sector (stretcher cover, mask, surgical gown, etc.) makes life easier by using. In particular, it will provide antibacterial effectiveness if applied to protective masks, which in the Covid- 19 pandemic are now part of everyday life, rather than medical textiles.

State of the Art:

The morphology (structure) of microcapsules varies mainly depending on the core material and the microencapsulation process. Microcapsules can be spherical or irregularly shaped. They can be single-core, multi-core or matrix in structure. In singlecore microcapsules, the core material is continuously wrapped by a shell. In multicore microcapsules, the core material is collected in different parts of the microcapsule and surrounded by shell material. In matrix-type microcapsules, the core material is homogeneously distributed within the shell material. (Kut, 2011).

Thanks to the microencapsulation technique, the core material can be protected from reactive, corrosive and harmful environment, it can gain better workability (increase in solubility, fluidity, etc.), its shelf life is increased, dangerous and toxic materials can be safely transported, enzyme and microorganism immobilization can be performed, taste and odor can be hidden, liquid substances can be transported in solid form and their release can be kept under control (Nelson, 2002; Rosenberg et al., 1990; Anal and Singh, 2007; Krasaekoopt et al., 2003; Champagne and Fustier, 2007; KOQ et al., 2010). Many techniques are used in the production of microcapsules. In the selection of the microencapsulation technique, Type of core material, Desired particle size, Permeability of the shell material, etc. Features like this are important. Microencapsulation technique should be chosen according to the targeted effect. (Kut, 2011).

At the beginning of the techniques used in microcapsule production; extruder, spray drying, in-situ polymerization, interfacial polymerization, coacervation and fluidized bed microencapsulation methods.

Developing technology has made functional product design a priority in the textile industry, as in every field. In addition to the aesthetic appearance of the products, their functionality, comfort features, not harming the health of the user and being economical are among the demands of the consumers. In addition, the fact that energy resources are becoming more expensive and limited, and the environmental awareness gradually develops, has made energy and water saving compulsory in the textile sector as in all areas of life. Functionality can be given to textile materials in fiber production, as well as mostly through finishing processes. Finishing processes, with the most general definition, are the processes applied to improve the attitude-appearance and usage properties of textile materials. There are many chemicals commonly used in finishing processes. The most distinctive feature of these chemicals is that they are not substantive (interest) in textile products. For this reason, applications made according to the impregnation method are frequently used in finishing applications in business environments. In addition, foamed application and coating methods have also been used in finishing processes in recent years. In the textile sector, the search for alternative methods to conventional methods has accelerated in order to maintain industrialization and protect the environment. Among these methods, ultrasonic (Kamel et al., 2009) and microwave energy use (Kim et al., 2003), plasma application (Karahan et al., 2009; Samanta et al., 2014), foamed application (Kut, 2011), coating methods ( Perelshtein et al., 2013) and microcapsule applications (Monllor et al., 2010; Yuan et al., 2009) stand out from other methods especially in terms of environmental and economic advantages. Microencapsulation technology is an important technique in terms of prolonging the effect of the functional finishing applied to the product (Re, 1998). It is seen as unrivaled, especially when effects such as controlled release are desired (Re, 1998). Microencapsulation can also be applied to other wet processes such as dyeing and printing. Environmental effects such as washing conditions and usage conditions limit the long-lasting use of many substances. Such substances are protected by a shell with the microencapsulation technique and their resistance to the environment is increased (Tan et al., 2003; Kim and Cho, 2002; Salatin et al., 2009; Huang and Yang, 2014; Martin et al., 2015; Ezhilarasi, 2013). Due to the long-term effect, it provides in textile finishing processes, the use of microencapsulation technique is frequently encountered in recent days (Li et al., 2013; Sathianarayanan et al., 2011). Microencapsulation is the encapsulation of various chemicals such as drugs, proteins, dyes or cosmetics in a liquid, gaseous or solid state in a suitable shell (Nesterenko et al., 2013; Nesterenko et al., 2014; Rajam and Anandharamakrishnan, 2015; Nunes et al., 2015). The encapsulated material is called the core (Istanbul Commerce University Journal of Science 15th Year Special Issue Spring 2016 11), and the coating material is called the wall, shell or wall material (Nesterenko et al., 2013). With the use of microencapsulation technique, controlled/delayed release to textile surfaces (Kut, 2011), taste, odor (Fei et al., 2015) and color masking, UV (Xu et al., 2013), heat (Pomianowski et al., 2012), oxidation ( Gupta et al., 2015), protection against acids and bases and stabilization of volatile compounds, antibacterial (Qimen, 2007), anti-microbiality (Balci, 2006), anti-fungal (Park et al., 2009), long-term flame retardancy ( Giraud et al., 2001), insect repellent (Miller et al., 2011) and heat insulation (Hawlader et al., 2003) properties can be gained. After the textile materials are produced in the desired construction (structure), various functional properties are gained to the fabrics by finishing processes. In terms of microcapsule production, the commercial microcapsule in our country is produced and sold by the German Rudolph company within the scope of Rudalf Duraner partnership.

Its microcapsules, which have the feature of giving freshness and coolness, contain frescolate and menthol.

TR201920466 "A Microcapsule Spraying System For the Production of Denim or NonDenim Products with Functional Properties And Its Working Method” the patent that Roteks Textile company received in 2019 is related to the use of a microcapsule spraying system for the production of denim and non-denim products with functional properties. The method described in this patent is the microencapsulation of cosmetic active substances with a spray system and their application to textiles. It has been stated that the spraying system causes less water, chemical and energy consumption compared to impregnation and extraction methods.

National patents related to the subject of invention:

TR2016/04040 “Using Microcapsules on Textile Surface in Apparel Industry” the patent application titled Defacto received in 2016 is related to the addition of different properties to textile products in the ready-made clothing sector by applying microcapsules in the finishing processes. In this method, microcapsule applied textiles; Microcapsules containing saltidine have anti-insect properties, capsules containing fresco late and menthol have cooling properties, capsules containing vitamin E have anti-aging properties, capsules containing brown seaweed have anti-cellulite properties, capsules containing some plant extracts have a thinning feature, capsules containing spice mixtures add fragrance.

TR2015/06062 “Seamless Bra with Microcapsule” the patent application titled Sun Textile’s patent in 2015 is related to three-dimensional honeycomb textured seamless bras containing microcapsules containing active ingredients of Dictyopterans membrenacea extract and apricot kernel oil. TR200505291 “Fibers and Non-Woven Textiles Finished with Micro Capsules” the patent application titled Fashion Chemicals received in 2002 concerns the application of microcapsules containing squalene, chitosan, retinol, caffeine, vegetable proteins and their hydrolysis products, carotenes and jojoba oil to fibers or non-woven textiles in finishing processes.

TR200800889 “Microcapsules Produced by Coacervation, containing a Pharmaceutical in Ethyl Cellulose Coating” the patent application titled Adare Pharma obtained in 2004 relates to microcapsules produced by coacervation, containing a pharmaceutical in an ethyl cellulose coating. Capsules produced in this way have been noted to have excellent taste masking and extended active ingredient release properties.

International patents on the subject of invention:

[EP2588652B1, 2019]: This invention relates to the application of active agents with different functions to fibers and textile surfaces by coating them with polymers.

[US9163205B2, 2010]: This invention relates to a process for making films from nonwoven webs containing filaments, fibers by converting filaments, fibers or nonwoven webs into films.

[CA2803625C, 2010]: This invention relates to a filament-forming material and methods that can be used to prepare such filaments for nonwovens where yarns, and in particular one or more active substances, are filamented or used in filaments.

[US20180338890A1, 2010]: This invention relates to forming a film layer on a filament, fiber or nonwoven surface containing an active agent to form a filament fiber or nonwoven surface that can disperse the active agent in its content.

[CA2803629C, 2010]: This invention relates to filaments, and more particularly to filaments comprising a filament forming material and an additive, particularly one or more active agents, non-woven webs using the filaments, and methods for making such filaments.

The applications most similar to the invention are as follows:

Patent application numbered WO2019243425 Al entitled "Microcapsule Preparation Process" relates to a new process for the preparation of fill-shell microcapsules. Microcapsules are also an object of the invention. Consumer products containing said microcapsules, particularly perfumed consumer products or flavored consumer products, are also part of the invention.

US5043161A “Small, oily, free-flowing, silky-smooth, talc-like, dry microcapsules and aqueous formulations containing them ” this disclosure is directed to the preparation of dry microencapsulated product, having an oily core material with microcapsule cell wall materials having a first cell wall of gelatin/polyvinyl methylether maleic anhydride copolymer (PVMMA)/carboxymethylcellulose (CMC) which is prehardened (crosslinked) with a material selected from the group consisting of formaldehyde, glyoxal and glutaraldehyde to which there is grafted formaldehyde and resorcinol which is then crosslinked with formaldehyde and urea, and aqueous formulations containing them. Approximately 97% of these microcapsules have a size less than 100 and more characteristically having a particle size peak distribution of 30 to 40 microns (microcapsular diameter). These microcapsules contain less than approximately 3 wt. % free oil and more characteristically less than about 1 wt. % free oil (non-micro- encapsulated oil) and have less free (unreacted) formaldehyde which can be extracted with water, than do prior art microencapsulated emollient materials. The dry microcapsules of this invention are free-flowing and have a silky-smooth feeling similar to that of talcum powder.

In the applications listed above, polymers are used as wall materials in the production of microcapsules and chemical binders are used to secure the capsules. This leads to toxicity. Description of the Invention:

This invention, eucalyptus and essential fatty featured antibacterial microcapsules applied to the textile material, and property; a property is high antibacterial, non-toxic biodegradable fact that the skin in lack.

The meeting of microencapsulation technology and textile enables the production of technical or functional textile surfaces.

The produced microcapsules consist of completely biodegradable ingredients, they do not contain any toxic substances for the human body and there is no toxicity for the environment. Microcapsules containing eucalyptus essential oil, which also has antibacterial properties, are not available in the literature. The HE (Health effect) codes found in the toxicity reports found in Pubchem data, the National Library of Medicine institution affiliated to the US National Health Agency, analyze the effects of chemicals on the health of living things. Glutaraldehyde has the code HE14 (Slight effects for eyes, nose, throat and skin) while glyoxal has the code HE 16 (Mild effects for eyes, nose, throat and skin). Based on these data, we think that it is more appropriate to use glyoxal on surfaces applied to textiles and in contact with human skin. In addition, the fact that the microcapsules contain less than 2% crosslinker prevents toxicity.

Description of the Figures:

This invention is described in more detail by means of sampling only, with reference to the October drawings hereinafter, in these drawings;

Figure 1 It is a schematic representation of the production steps of the microcapsule.

Figure 2 It is a schematic representation of the production steps of the microcapsule. Figure 3 Optical microscope image of the microcapsules in the coacervation stage. (lOOx magnification)

Figure 4 Optical microscope image of microcapsules after adding glutaraldehyde. (lOOx magnification)

Figure 5 It is an optical microscope image of microcapsules after the addition of glyoxal. (lOOx magnification ratio)

Figure 6 They are optical microscope images of textile surfaces, a) meltblown surface b) glyoxalli microcapsule applied surface c) gluteraldehyde microcapsule applied surface (lOOx magnification ratio)

Figure 7 Comparative FT-IR analysis of eucalyptus essential oil/gelatin/arabic, gum/glyoxal microcapsule/glutaraldehyde microcapsule.

Figure 8 Comparative FT-IR spectrum of microencapsulated meltblown surfaces with glutaraldehyde and glyoxal.

Figure 9 Glyoxal microcapsule applied meltblown surface SEM images.

Figure 10 Glyoxal microcapsule applied meltblown surface SEM images.

Figure 11 Glyoxal microcapsule applied meltblown surface SEM images.

Figure 12 Glyoxal microcapsule applied meltblown surface SEM images.

The figures to help understand the present invention are numbered as indicated in the attached image and are given below along with their names. Description of References:

10. Heating

20. Preparation

30. Preparation of The Solution

40. Mixing 1

50. Mixing 2

60. Adjusting to pH 1

70. Mixing 3

80. Mixing 4

90. Adjusting to pH 2

100. 30 min. Mixing

110. Setting PH 3.5- 4

120. Stabilization

130. Termination of the Coacervation Phase

140. Lowering the Temperature

150. Hardening

160. Splitting the Mixture into 2

170. Addition

180. 120 Min. Mixing

190. Resting

GM. Microcapsule with Glutaraldehyde

GIM. Glyoxal Microcapsule

A. Gum Arabic

J. Gelatin

O. Eucalyptus Oil

X. Melt blown Surface with Glutaraldehyde Microcapsule Applied

Y. Melt blown Surface with Glyoxal Microcapsule

Description of The Invention: The invention consists of eucalyptus essential oil as oil, powdered gelatin (J) (bovine gelatin-type B) and gum arabic (A) as polymer material, glutaraldehyde (25%) and glyoxal (40%) as crosslinker, acetic acid as pH adjuster. (99.8%) and sodium hydroxide (99%).

Invention; Heating (10) 1500 mL of pure water to 50-60°C, preparation of 1 M NaOH solution (20), Preparation of the solution (30), of 1 M acetic acid solution mixture and, Mixing 1 (40), 16 g gelatin and 400 ml distilled water at 50-60°C at 400 rpm for 30 minutes, mixing 3 (50), 160 ml of eucalyptus essential oil and 240 ml of pure water at 50-60°C for 30 minutes at 400 rpm 1 M NaOH solution of gelatin-pure water mixture adjusting to pH 7 1 (60) with mixing gelatin - pure water and eucalyptus essential oil - pure water mixture mixing 3 (70) at 50-60°C for 30 minutes at 400 rpm, 16 g gum arabic - 400 ml pure water mixture is prepared and 50 Mixing 4(80) at -60°C for 30 minutes at 400 rpm the gum arabic - water mixture adjusting to pH 72 (90) with 1 M NaOH solution, stabilization (120) of the complexes by mixing all the prepared materials together at 50- 60°C at 1000 rpm for 30 minutes mixing (100), setting pH to 3.5-4 (110) with 1 M acetic acid, resting for 90 minutes at room temperature, Termination of the coacervation phase (130) by adjusting the pH to 9.5-10 with 1 M NaOH solution leaving the ice bath to lower the temperature (140) to 5°C keeping the shells in an ice bath at 5°C for 60 minutes splitting the mixture into 2 (160), addition (170) of glutaraldehyde to the mixture at 5°C to one of the mixtures, glyoxal to the mixture at 5°C to the other mixing the mixtures at 1200-1500 rpm at room temperature for 120 minutes mixing (180), and resting (190) the mixtures at 4°C for 600 minutes (Figure 1, Figure 2).

Microcapsules become usable by being applied on textile surfaces by absorbing 30 g/m2 meltblown nonwoven surface produced from 100% polypropylene and drying the samples at room temperature (20 C° ± 2) for 8 hours. Detailed Description of The Invention:

Chemicals Used

The invention as an oil eucalyptus essential oil, gelatin powder, a polymer material (J) (bovine gelatin Type B) and gum Arabic (A), cross-connector glutaraldehyde (25%) and glioksal (%40), acetic acid as a pH adjuster (%99,8) and sodium hydroxide (99%) it contains.

Devices Used

In the experimental study, laboratory type heater (hot&stirrer, Tepe MS300HS) to adjust the temperature of the solutions in microencapsulation and to keep it constant, digital thermometer (Loyka) for temperature measurements of solutions, digital pHmeter (Hanna HI2211-02 Table type pHmeter, Germany) for pH measurements of solutions, in microencapsulation experiment setup, mechanical stirrer (0-2200 rpm Isolab Laborgerate Gmbh, Germany) in the mixing stages, examination of the morphology of the produced microcapsules, particle size analysis and optical microscope to detect the presence of microcapsules on microcapsule applied textile surfaces (BAB Bs200Doc, Turkey), molecular structure of microcapsules and microcapsule applied textile surfaces FT-IR Spectroscopy (Perkin Elmer Frontier FT-IR Spectrophotometer Spectrum 400, USA) for high level chemical structure analysis, SEM Scan for detecting the presence of microcapsules on microcapsule applied textile surfaces, examining microcapsule morphology and particle size analysis. All-electron microscope (Zeiss Evo® LS10, Germany) instruments were used. In order to determine the antibacterial activity of microcapsules, the antibacterial activity test (AATCC 147- 2016) was carried out in an accredited laboratory, Ekoteks Laboratory and Gbzetim A.§.

Microencapsulation of Eucalyptus Essential Oil with Complex Coacervation Method

In the first step of microencapsulation, aqueous solutions of eucalyptus essential oil, which is the core material, were prepared at a ratio of 1 :1 (50-60°C) and aqueous solutions of gum arabic (A) and gelatin (J) were mixed at 400 rpm using a mechanical mixer. With the addition of acetic acid, the pH was adjusted to the range of 3.5-4 (pH where the polymers are electrolytes) and the polyanion (gum arabic) - polycation (gelatin) complex formation was started and the mixture was left to rest for the stabilization of the complexes. Then, the pH was adjusted to 9 by adding sodium hydroxide and thus the complex formation (coacervation step) was stopped. The mixture was cooled to 5°C in an ice bath and the mixture was left at this temperature for 1 hour to harden the microcapsule shell structures. Since two different crosslinkers will be used, after the mixture is divided into 2, the crosslinker glutaraldehyde and crosslinker glyoxal are added to stabilize the microcapsules. Microcapsules were rested at 4°C for 6 hours. The wall/core ratio of 1 :5 was applied in the microcapsules. In Figures 1 and 2, the production of eucalyptus essential oil microcapsules by the complex coacervation method is shown with all its steps.

Application of Microcapsules to Textile Surfaces

The microcapsules produced in the study were applied to the 30 g/m2 meltblown nonwoven surface made of 100% polypropylene by the impregnation method. The samples were dried at room temperature (20°C±2) for 8 hours.

Evaluation of Optical Microscope Analysis

According to the particle/size analysis given in the table above, the size of the capsules in the coacervation stage ranged from 5.62 pm to 38.99 pm, while the average capsule size was 19.70 pm. While the size of the capsules using glutaraldehyde ranged from 5.46 pm to 36.31 pm, the average capsule size was determined as 17.10 pm. The size of the capsules using glyoxal ranged from 6.14 pm to 63.82 pm, while the average capsule size was measured as 18.37 pm. When the images and dimensions of the microcapsules at the coacervation stage and the images examined after the crosslinker addition were compared, it was determined that the deviation in particle sizes in the use of glutaraldehyde was less than the use of glyoxal and a more regular distribution was achieved. In addition, the surface images of melt blown (Figure 6) applied microcapsules with the addition of glutaraldehyde and glyoxal crosslinker, which were not applied microcapsules, were examined under an optical microscope and the presence of microcapsules on the surfaces was determined.

Evaluation of FT-IR Analysis

Eucalyptus essential oil as the core material used in the produced microcapsules, biopolymers as the wall material, gum arabic (A) and gelatin (J), FT-IR analysis for Microcapsule with Glutaraldehyde (GM) and Glyoxal Microcapsule (GIM) are presented in Figure 7. The characteristic bands for eucalyptus essential oil are the band showing C-H stresses at 2967 and the band showing C-N stresses at 1214. In Figure 8, these bands are seen for eucalyptus essential oil. In the structure of the microcapsules, the band at 2967 was not visible, but the band at 1214 showing the C-N tensions was observed. The characteristic bands for gum arabic (A) are bands showing N-H stretches at 3300 and negatively charged carboxyl groups at 2925. The characteristic bands for gelatin (J) are bands showing positively charged amine groups at 3400 and C-N stretches at 1078. The bands showing that gum arabic (A) and gelatin (J) react in the presence of the crosslinker and that new primary, secondary and tertiary amide bonds are formed in the medium are characteristic bands in 1636, 1545 and 1241. These bands were seen in glutaraldehyde microcapsules in 1636, 1468 and 1297, in glyoxal microcapsules (GIM) in 1638, 1375, and their application to microcapsules with antibacterial properties and textile materials with eucalyptus essential oil.

Figure 8 shows the FT-IR spectrum for Melt blown Surface with Glyoxal Microcapsule (Y) treated with microcapsules with glutaraldehyde and glyoxal. Bands showing the presence of eucalyptus essential oil in the structure in the surface spectra were observed at 2840 cm' ¹ on the microcapsule with glutaraldehyde (GM) surface and at 2921 cm' ¹ on the glyoxal microcapsules (GIM) surface. Bands showing the presence of gelatin (J) in the structure on the microencapsulated surfaces were observed at 1599 cm-1 on the microcapsule with glutaraldehyde (GM) surface and at 1634 cm-1 on the glyoxal microcapsules (GIM) surface. These results show that both glutaraldehyde and glyoxal microcapsules (GIM) have been successfully applied to textile surfaces.

Evaluation of SEM Analysis

SEM images were taken from the surface on which the microcapsule was applied, and the morphology of the microcapsules, the capsule dimensions and the appearance on the polypropylene fibers were examined. Above are SEM images at different magnifications taken from meltblown (Figure 9, Figure 10, Figure 11, Figure 12) surfaces treated with glyoxal and microcapsule with glutaraldehyde (GM). According to the particle size analysis performed on the SEM images taken from the microcapsule- applied surfaces, it was determined that the size of the microcapsules varied between 1.00 pm and 17.96 pm. While the average capsule size was 5.56 pm in the microcapsule application using glutaraldehyde as the crosslinker, the average capsule size was measured as 2.89 pm in the microcapsule application using glyoxal as the crosslinker. All the capsules displayed were found to be non-porous. In addition, it was determined from the images that the microcapsules were generally in smooth spherical morphology and attached to the fibers on the applied surfaces, but generally appeared embedded in the excess polymers, and the relatively large and dense capsules that could be seen in the optical microscope were deformed in the coating and vacuum processes for SEM imaging.

Evaluation of Antibacterial Efficacy Analysis AATCC 147: According to the 2016 standard, antibacterial activity test was applied to 6 sample surfaces. The results are given in the table above. According to the test results, microorganism growth has been observed on the surface that has not been treated with number 1, and the antibacterial activity test result is ineffective. No microorganism growth was observed in the surface test impregnated with eucalyptus essential oil Number 2, the inhibition zone was determined as 2.25 mm for Staphylococcus aureus gram (+) bacteria and for Klebsiella pneumoniae gram (-) bacteria, and the antibacterial activity test result was recorded as effective. No microorganism growth was observed in the melt blown surface (X) test, on which microcapsules with glutaraldehyde number 3 were applied, and the inhibition zone of gram (+) and gram (-) bacteria was determined as 2.2 mm, and the antibacterial activity test result was recorded as effective. Number 4 glioksalli meltblown microcapsules applied to the surface (Y) of the test microorganism unprecedented growth of gram (+) 2.1 mm inhibition zone for bacteria, gram(-) bacteria for antibacterial activity and 2.2 mm inhibition zone were recorded as the test result has been determined to be effective. Number 5 microorganism growth was observed on the meltblown surface (X) where 50% concentration of gluteraldehyde microcapsule was applied and antibacterial activity was ineffective as a result of the test.No microorganism growth was observed in the meltblown surface (Y) test, on which glyoxal microcapsule number 6 was applied at 50% concentration, the inhibition zone of gram(+) and gram(-) bacteria was determined as 2.2 mm, and the antibacterial activity test result was recorded as effective. These results confirmed the antibacterial activity of eucalyptus essential oil in the literature. At the same time, the antibacterial activity of the surfaces on which the microcapsules produced using both glutaraldehyde crosslinker and glyoxal crosslinker were applied was determined. These tests were carried out 40 days after the production of the capsules and this shows us that the eucalyptus essential oil is protected by encapsulation and has a controlled release on the surface. The fact that the capsule with glutaraldehyde is ineffective and the capsule with glyoxal is effective on the surfaces where 50% concentration is applied shows that the antibacterial activity of the microcapsules produced by using the glyoxal crosslinker is higher.