KR20130078924A - Method for manufacturing nano fibered non-woven fabrics having uv-shielding and light-stabilized properties - Google Patents

Abstract

PURPOSE: Method of manufacturing nanofiber non-woven fabric is provided to concurrently give sun screen and light-stabilized property through a method which electric-spins and intercrosses a spinning solution. CONSTITUTION: Method of manufacturing nanofiber non-woven fabric comprises; (a) a step of preparing a spinning solution by melting and dispersing sunscreen, light-stabilizing agent and polymer for nanofiber formation in a solvent; (b) a step of obtaining a nanofiber web of polymer by electric-spinning the spinning solution; (c) a step of obtaining nanofiber non-woven fabric by thermally fusing is the nanofiber web. [Reference numerals] (AA) Step of manufacturing spinning solution containing organic sun block, organic light fastness stabilizing material; (BB) Step of sole electric radiation; (CC,HH) Step of collecting nano fiber; (DD,II) Step of processing nano fiber calendar; (EE) Step of manufacturing spinning solution containing inorganic sun block; (FF) Step of manufacturing spinning solution containing organic light fastness stabilizing solution; (GG) Step of cross electric radiation

Description

Manufacturing method of nanofiber nonwoven fabric with UV protection and light stabilization property {METHOD FOR MANUFACTURING NANO FIBERED NON-WOVEN FABRICS HAVING UV-SHIELDING AND LIGHT-STABILIZED PROPERTIES}

The present invention relates to a method for producing a nanofiber nonwoven fabric, and more particularly, to a method for producing a nanofiber nonwoven fabric provided with UV blocking and light stabilization properties obtained by electrospinning a polymer solution containing a sunscreen and a light stabilizer.

The electrospinning method is a technique of obtaining a three-dimensional nonwoven fabric composed of nanofibers having a diameter of less than 1 μm obtained by applying a high voltage to a polymer solution. Nonwoven fabrics composed of such nanofibers have very weak characteristics in terms of ultraviolet light or light resistance because their diameters are tens to thousands of times smaller than fibers manufactured by conventional spinning methods such as solution spinning or melt spinning.

 Organic synthetic fibers undergo physical and chemical reactions during their use in a variety of environments, slowly losing their intrinsic properties and eventually becoming intolerable to practical use. These causes include light, heat, mechanical action, radiation, chemicals, microorganisms, moisture, air and pollutants, and deterioration due to the complex factors of the environment changes the appearance and shape. Therefore, in the production of synthetic fibers, in order to impart UV blocking properties and light resistance properties, a method of adding a light stabilizer or a sunscreen agent in a polymer polymerization step or giving a function in a post-treatment process is used.

As a method of imparting UV blocking properties in the polymerization step of the polymer, melting and solution by adding organic compounds such as benzotriazole and benzophenone, or inorganic compounds such as zinc oxide, titanium oxide, talc, and kaolin to absorb and shield ultraviolet rays Fibers have been produced by methods such as spinning, imparting UV blocking properties. As a method for imparting light resistance, a method of mixing and spinning an antioxidant, which is a radical scavenger, into a spinning solution, or applying a UV absorber or an antioxidant in a post-treatment process is used.

Japanese Patent No. 3053248 Republic of Korea Patent Publication No. 10-2010-0086346 For example, Japanese Patent No. 3053248 adds a specific inorganic compound having ultraviolet shielding properties such as zinc oxide and titanium oxide to uniformly disperse the particles in a particulate state to produce polyester fibers having excellent UV shielding properties without trimming. A method of doing this is disclosed. In addition, Korean Patent Laid-Open Publication No. 10-2010-0086346 discloses a phosphorus (P) -based flame retardant in the sheath part and an inorganic sunscreen agent such as titanium oxide and zinc oxide in the core part to radiate ultraviolet rays and A method of simultaneously providing flame retardancy is disclosed. However, the prior art is a fiber produced by the conventional spinning method such as melt spinning or solution spinning, the diameter of the fiber is composed of several tens to thousands of times larger than the nanofiber, so that the additive that gives UV protection and flame retardant properties There is a disadvantage in that the probability of distributing on the surface is remarkably low to increase the content of the additive unnecessarily. In addition, the melt spinning method of 300 ℃ or more has a problem in that it is difficult to use organic sunscreens or radical scavengers, which are excellent in properties and relatively inexpensive compared to inorganic systems, and thus have a disadvantage in that the manufacturing technology is limited to polyester fibers. have. Furthermore, the prior arts are polymerized and dried, followed by melt spinning to prepare fibers, and heat treatment and post-treatment processes such as stretching, so that the process cost can be increased compared to the manufacturing process of nanofibers, There are limitations in the manufacture of nonwovens or woven fabrics and their use is very limited.

The present invention is to solve the above problems, a method of electrospinning alone by mixing a sunscreen and a light stabilizer together with a spinning solution or a spinning solution containing a sunscreen and a radiation solution containing a light stabilizer It is an object of the present invention to provide a method for producing a nonwoven fabric of nanofibers that can provide UV protection and light stabilization at the same time by separately preparing each of these spinning solutions by cross-electrospinning.

Other objects of the present invention will be clearly understood by description of specific embodiments of the present invention and the like.

According to the present invention to achieve the above object, (a) preparing a spinning solution by dissolving and dispersing a sunscreen and a light stabilizer in a solvent together with a polymer material for forming nanofibers; (b) electrospinning the spinning solution to obtain a nanofiber web of polymer; And (c) heat-sealing the nanofiber web to provide a nanofiber nonwoven fabric, wherein the nanofiber nonwoven fabric is provided with UV blocking and light stabilization properties.

In addition, according to the present invention, (a) preparing a spinning solution by dissolving and dispersing a sunscreen and a light stabilizer in a solvent together with a polymer material for forming nanofibers, respectively; (b) cross electrospinning the spinning solutions to obtain a nanofiber web of polymer; And (c) heat-sealing the nanofiber web to provide a nanofiber nonwoven fabric, wherein the nanofiber nonwoven fabric is provided with UV blocking and light stabilization properties.

As the sunscreen agent, an organic sunscreen agent such as benzotriazole or benzophenone, or an inorganic sunscreen agent such as zinc oxide, titanium oxide, or zinc oxide mixture is used for forming nanofibers. It is characterized by containing 0.1 to 10% by weight relative to the polymer material.

As a radical scavenger to impart light stabilization properties, phenolic antioxidants, amine-based light stabilizers (HALS), phosphorus antioxidants, sulfur-based antioxidants, etc. may be used alone or in combination of two or more to form nanofibers. It is characterized in that it comprises 50 ~ 10,000ppm compared to the polymer material.

 As the inorganic sunscreen agent, a zinc oxide-based, titanium oxide-based, zinc oxide-titanium oxide-based mixture has a particle size in the range of 5 nm to 1000 nm, preferably in the range of 5 nm to 100 nm. It is advantageous in preventing clogging and in effect.

When the electrospinning solution is prepared by mixing the UV blocking agent and the light stabilizing agent together, and electrospinning alone, the organic UV blocking agent and the organic light stabilizing agent are mixed. The spinning solution containing the sunscreen and the spinning solution containing the light stabilizing agent are separately prepared, and the spinning solution is crossed by spinning. The reason for this is that in the case of inorganic sunscreens such as titanium oxide, coloring and discoloration may occur due to reaction with the light stabilizer, and there is a fear of forming a complex to provide a cause for clogging of the radiation nozzle.

The polymer material used for electrospinning may include polyurethane (PU), polyvinyl alcohol (PVA), polyvinylidene fluoride (PVDF), polylactic acid (PLA), polycarbonate (PC), polyacrylonitrile ( PVA), polystyrene (PS), polysulfone (Polysulfone), polyetherimide (PEI), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), polyethersulfone (PES), etc. Hydrophobic, hydrophilic polymers may be composed alone or in combination, and are not limited to specific materials. In particular, in the case of blend spinning by mixing two or more polymers, phase separation or uniform mixing may be difficult. In this case, it is preferable to spin using a cross-electrospinning method.

 The solvent used when preparing the electrospinning solution is dimethyl formamide (di-methylformamide, DMF), dimethyl acetamide (DM-Ac), THF (tetrahydrofuran), acetone (Acetone), alcohol (Alcohol) 1, selected from the group consisting of chloroform (Chloroform), dimethyl sulfoxide (DMSO), dichloromethane, acetic acid (acetic acid), formic acid (N-Methylpyrrolidone), fluorinated alcohols, water, etc. It is characterized by more than one species.

The electrospinning method is selected from the group consisting of pure electrospinning, electrospray, electrobrown spinning, centrifugal electrospinning, flash-electrospinning, and the like. It is characterized by being a species.

The electrospun nanofibers are fused between nanofibers and nanofibers by thermal bonding, rolling, calendering, etc. in a temperature range where decomposition of the used polymer and additives does not occur, wherein the use temperature range is 60 C-150 degreeC is preferable.

The nanofiber nonwoven fabric provided according to the present invention is endowed with UV protection and light stabilization properties as compared with conventional nanofibers, and can be applied to various industrial textile products as well as a core material of various outdoor products for clothing. In addition, the nanofiber nonwoven fabric according to the present invention can be utilized in various fields by complexing with various base materials, and can implement a highly reliable product by improving the light stabilization characteristics compared to the conventional nanofibers.

1 is a view showing the manufacturing process of the nanofiber nonwoven fabric provided with UV protection and light stabilization properties of the present invention,
Figure 2 is a schematic diagram showing a method of manufacturing a nanofiber nonwoven fabric provided with UV protection and light stabilization properties of the present invention, (a) is a single electrospinning, (b) is a cross-electrospinning method, respectively;
3 is a scanning electron micrograph of a polyurethane nanofiber web containing a sunscreen and a light stabilizer according to one embodiment of the present invention; (a) x 1K, (b) x 5K magnification,
4 is a scanning electron micrograph after undergoing a hot plate calendering process of a polyurethane nanofiber web containing a sunscreen and a light stabilizer according to another embodiment of the present invention; (a) x 1K, (b) x 5K magnification,
5 is a scanning electron micrograph of a nanofiber web prepared by cross-electrospinning of polyurethane nanofibers and PVDF nanofibers containing a sunscreen and a light stabilizer, which is another embodiment of the present invention; (a) x 1K, (b) x 5K magnification.

In the present invention, first, by dissolving and dispersing an additive such as a radical scavenger as a sunscreen and a light stabilizing agent in a solvent together with a polymer to prepare a spinning solution at an electrospinable concentration, electrospinning alone, or each of these additives separately After dissolving in a solvent with a polymer to prepare a spinning solution separately, these spinning solutions are cross-electrospun to obtain a nanofiber web. The nanofiber web obtained as described above is subjected to a heat fusion process such as hot plate calendering to produce a nanofiber nonwoven fabric provided with UV blocking and light stabilization properties.

 Hereinafter, the present invention will be described in more detail in each step.

Preparation of spinning solution containing sunscreen and light stabilizer

In the case of single electrospinning with one spinning solution, the organic sunscreen and the radical scavenger, which is a light stabilizer, are dissolved in a solvent at a radiation concentration by 0.1-10 wt% and 50-10,000ppm, respectively, relative to the polymer material. Prepare the solution.

In the preparation of the spinning solution, when the content of the sunscreen and the radical scavenger is less than 0.1% by weight and 50ppm, respectively, the addition amount is too small, so it is difficult to substantially expect the UV absorption effect and the light stabilization characteristics, whereas 10% by weight, 10,000 It is not preferable to exceed the ppm because it will cause a rise in cost.

 On the other hand, when the inorganic sunscreen is used, coloration, discoloration, etc. may occur due to the reaction with the light stabilizer, and phase separation of the spinning solution when blending two or more kinds of polymer components to give functionality to the final product. If you do not use the same solvent occurs. Therefore, the cross-electrospinning method is used at this time.

On the other hand, the content of the polymer in the spinning solution prepared in the present invention is 5 to 60% by weight is suitable, if the content is less than 5% by weight or more than 60% by weight may be difficult electrospinning itself may occur Not.

Formation of Polymer Nanofiber Webs Conferred UV Protection and Light Stabilization Properties

The prepared spinning solution is transferred to a spin pack using a metering pump, and a high voltage regulator is used to apply a voltage to the spin pack to perform electrospinning to form a nanofiber web on the current collector plate. do.

At this time, the voltage used is a voltage capable of radiation in the range of 0.5kV ~ 100kV, the current collector can be grounded or charged to the negative pole. The current collector plate is composed of an electrically conductive metal, a release paper, a nonwoven fabric, and the like, and in the case of the current collector plate, a collector is preferably attached to the fiber to facilitate the concentration of fibers during spinning.

 During electrospinning, the distance between the spin pack and the current collector plate is adjusted to 5 ~ 50㎝, and the discharge amount of discharge is discharged at 0.01 ~ 5cc / hole · min per hole using a metering pump, and the temperature and humidity can be controlled during spinning. It is desirable to spin in an environment of 10-90% relative humidity in the chamber.

Nanofiber Nonwoven Fabric

In order to form the obtained nanofiber web into a nonwoven fabric, a heat fusion process is used. Hot plate calendering, a typical thermal fusion process, passes the nanofiber web obtained by single electrospinning or cross electrospinning through a temperature-controlled calendering roll to induce thermal bonding between the nanofibers so that the nanofibers do not escape. The heat treatment temperature is set in consideration of the additive used and the glass transition temperature of the polymer. At this time, the heating temperature at the time of calendering is suitable about 60 ~ 150 ℃. If the processing temperature is less than 60 ℃, the degree of binding between the nanofiber and the nanofiber is small, there is a possibility that the nanofibers can be separated, whereas if the processing temperature exceeds 150 ℃, the polymer melts and the three-dimensional porous structure may be destroyed. This is undesirable.

The configuration of the method for manufacturing a nanofiber nonwoven fabric provided with UV blocking and light stabilization properties according to the present invention described above is shown in FIG. 1, and a conceptual diagram of the single electrospinning method and the cross electrospinning method described above are illustrated in FIG. 2. It is shown in (a) and (b), respectively.

(Example)

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are merely to illustrate the invention, it will be apparent to those skilled in the art that the scope of the invention is not to be construed as limited by these examples.

Example 1

In solvent THF / DMAc (50/50 vol.%), 15% by weight of polyurethane resin as polymer, 5% by weight of 2- (2'-Hydroxymethylphenyl) benzotrizaole, a benzotriazole-based sunscreen, as compared with polymer As a stabilizer, a spinning solution was prepared by dissolving a brand name Tinuvin 770 which is a amine light stabilizer (HALS), which is a radical scavenger, to 100 ppm relative to a polymer material.

The prepared spinning solution using the same nozzle as the single electrospinning method of FIG. 2 (a) using an applied voltage of 25 kV, a distance of 20 cm between the spinneret and the current collector, and a discharge amount of 30 ° C. at 0.05 cc / g · hole. And electrospinning at relative humidity of 60%. The scanning electron micrograph of the nanofiber web thus obtained is shown in FIG. 3, and from the results of FIG. 3, the distribution of the fiber diameter was about 400-700 nm and the average fiber diameter was about 500 nm.

The polyurethane nanofiber web prepared by the above method was calendered by passing through a hot plate preheated to 100 ° C. in advance to heat-bond nanofibers to prepare a nonwoven fabric. Fig. 4 is a scanning electron micrograph showing the surface of the nanofiber web calendered by the present example. 4, it can be seen that the nonwoven fabric is formed by thermal fusion between the nanofibers and the nanofibers.

Example 2

A spinning solution was prepared in a solvent THF / DMAc (50:50 vol.%) Such that 15% by weight of polyurethane was used as a polymer and 5% by weight of titanium oxide particles having an average size of 20 nm as a sunscreen. A spinning solution was prepared such that 15 wt% of PVDF as a polymer in Acetone / DMAc (10:90 vol.%) And 100 ppm of ADK STAB PEP-36 (product of densification product), which is a phosphorus antioxidant, as a light stabilizer.

The prepared spinning solution was applied to the applied voltage 25kV, the distance between the spinneret and the current collector 20cm, discharge amount 0.05cc / g / minute per minute by the method of Figure 2b, the radiation chamber temperature 30 ℃, 60% relative humidity The cross-electrospinning was performed at to obtain nanofiber webs with excellent UV protection and light stabilization properties composed of two-component polymers. The obtained nanofiber web was passed through a calender roll preheated to 140 ° C. to obtain a bicomponent nanofiber nonwoven fabric.

The scanning electron micrograph of the nanofiber web obtained in this way is shown in FIG. 5, From the result of FIG. 5, it can be confirmed from this example that a different fiber diameter distribution is shown by cross-radiation. That is, the fiber diameter distribution of the polyurethane polymer was about 500-700 nm, which is larger than that of the PVDF, and the PVDF showed 200-400 nm.

Example 3

In the same manner as in Example 1, a 50:50 mixture of 5% by weight of benzotriazole, a sunscreen agent, and a light stabilizer HALS-based Tinuvin 770 and a phosphorus-based antioxidant ADK STAB PEP-36 were prepared in the polyurethane polymer. The nanofiber nonwoven fabric was prepared in the same manner as in Example 1 to 100ppm relative to the polymer.

Comparative Example 1

Polyurethane nanofibers without the addition of a sunscreen and light stabilizer were electrospun under the same conditions as in the method of Example 1 to obtain a polyurethane nanofiber nonwoven fabric.

Comparative Example 2

Polyvinylidene fluoride nanofibers to which the sunscreen and the light stabilizer were not added were electrospun under the same conditions as in the method of Example 2 to obtain a polyvinylidene fluoride nanofiber nonwoven fabric.

<Characteristic evaluation>

The nanofiber nonwoven fabric prepared by the method of the present invention was measured using a nanofiber prepared by the method of Comparative Example 1 and a spectrophotometer having a wavelength of 320 to 390 nm to calculate ultraviolet ray shielding percentage (%). ), And the results are shown in Table 1. Herein, when the UV shielding ratio was less than 10%, it was determined that the UV blocking property was excellent.

 UV shielding rate (%) = 100-measured sample transmittance ..... Equation (1)

UV shielding rate division Polymer Electrospinning Method Sunscreen Light stabilizer UV shielding rate Example 1 PU Sole spinning Benzotriazole HALS 8.5% Example 2 PU / PVDF Cross radiation Titanium oxide HALS 7.8% Example 2 PU Sole spinning Benzotriazole HALS / take over 6.8% Comparative Example 1 PU Sole spinning - - 25% Comparative Example 2 PVDF Sole spinning - - 20%

As shown in Table 1, it can be seen that the UV shielding rate according to the embodiment of the present invention is very excellent compared to the comparative examples, especially, when the HALS and phosphorus antioxidant, which is a light stabilizer, are used in combination It can be seen that it rises.

The nanofiber nonwoven fabric provided by the method of the present invention is not only a moisture-permeable waterproof fabric, but also a wallpaper, a blind, a curtain material which requires UV protection and light stabilization properties, as well as interior products, automotive interior materials, agricultural nonwoven fabrics, filter materials, etc. It can be applied to various applications.

Claims (8)

(a) dissolving and dispersing a sunscreen and a light stabilizer in a solvent together with a polymer material for forming nanofibers to prepare a spinning solution;
(b) electrospinning the spinning solution to obtain a nanofiber web of polymer; And
(c) heat-sealing the nanofiber web to obtain a nanofiber nonwoven fabric, the method of manufacturing a nanofiber nonwoven fabric provided with UV protection and light stabilization properties. (a) preparing a spinning solution by dissolving and dispersing a sunscreen and a light stabilizer separately in a solvent together with a polymer material for forming nanofibers;
(b) cross electrospinning the spinning solutions to obtain a nanofiber web of polymer; And
(c) heat-sealing the nanofiber web to obtain a nanofiber nonwoven fabric, the method of manufacturing a nanofiber nonwoven fabric provided with UV protection and light stabilization properties. The method according to claim 1 or 2,
The sunscreen is selected from organic sunscreens including benzotriazole and benzophenone, and inorganic sunscreens including zinc oxide, titanium oxide, and a mixture of zinc oxide and titanium oxide. Method for producing a nanofiber nonwoven fabric provided with UV protection and light stabilization properties, characterized in that at least one. The method according to claim 1 or 2,
As the light stabilizer, a phenolic antioxidant, an amine light stabilizer (HALS, Hindered Amine Light Stabilizers), a phosphorus antioxidant, and a sulfur scavenger including a sulfur-based antioxidant are used alone or in combination of two or more. Method for producing a nanofiber nonwoven fabric provided with UV blocking and light stabilization properties. The method of claim 3,
The content of the sunscreen is a method of manufacturing a nanofiber nonwoven fabric given UV blocking and light stabilization properties, characterized in that 0.1 to 10% by weight compared to the polymer material for forming the nanofiber of the spinning solution. 5. The method of claim 4,
The content of the radical trapping agent is a method of producing a nanofiber nonwoven fabric given UV blocking and light stabilization properties, characterized in that 50 ~ 10,000 ppm compared to the polymer material for forming the nanofiber of the spinning solution. The method according to claim 1 or 2,
Polymer materials for forming nanofibers used in the electrospinning include polyurethane (PU), polyvinyl alcohol (PVA), polyvinylidene fluoride (PVDF), polylactic acid (PLA), polycarbonate (PC), polyacrylic Ronitrile (PVA), polystyrene (PS), polysulfone (Polysulfone), polyetherimide (PEI), polyvinylchloride (PVC), polymethacrylate (PMMA), polyethersulfone (PES) A method for producing a nanofiber nonwoven fabric provided with UV blocking and light stabilization properties, characterized in that the hydrophobic and hydrophilic polymers such as) alone or in combination of two or more. The method according to claim 1 or 2,
Thermal fusion of the nanofiber web is a nanofiber nonwoven fabric given UV blocking and light stabilization properties, characterized in that carried out at a temperature range of 60 ℃ to 150 ℃ by any one method selected from thermal bonding, rolling, and calendering Manufacturing method.

Images