Lyocell fiber and its manufacturing method

Abstract

Provided are a lyocell fiber capable of maintaining a temperature regulation function for a long period of time and absorbing formalin, and a method for producing the same. 【Solution means】The lyocell fiber contains cellulose, microcapsules having a core-shell structure, and a formalin scavenger. The microcapsules are cross-linked with the lyocell fiber matrix and the formalin scavenger. The core of the microcapsules contains a phase change material and a nanonucleating agent, and the shell of the microcapsules contains a melamine-modified urea formaldehyde resin prepolymer. The method for producing a lyocell fiber includes a spinning dope preparation step of mixing cellulose pulp, N-methylmorpholine-N-oxide, microcapsules having a core-shell structure, and a formalin scavenger and performing post-treatment, a spinning step of spinning the spinning dope obtained through the spinning dope preparation step, and a microwave treatment step of subjecting the yarn obtained through the spinning step to a microwave treatment step.

Description

Technical Field

[0001] The present invention relates to lyocell fibers and a method for producing the same.

Background Art

[0002] With the development of science and technology and the improvement of people's living standards, the fiber industry is gradually developing in the direction of functionalization and intelligentization, and temperature-regulating fibers are an important type among them. Temperature-regulating fibers have a two-way automatic temperature-regulating function, and utilize phase change materials (PCM) to release or absorb latent heat in the phase change process to achieve the purpose of temperature regulation.

[0003] Most of the existing temperature-regulating fibers are based on viscose fibers. For example, Patent Document 1 discloses a method for producing temperature-regulating cellulose fibers having a temperature-regulating function. Patent Document 2 discloses viscose fibers and a method for producing the same.

[0004] The spinning process of the fibers disclosed in Patent Documents 1 and 2 is long, and corrosive chemical raw materials such as sodium hydroxide, carbon disulfide, and sulfuric acid are used in the process, resulting in serious environmental pollution. In view of this, temperature-regulating fibers based on lyocell fibers have emerged.

[0005] Lyocell fibers are regenerated cellulose fibers produced by dissolving cellulose in N-methylmorpholine-N-oxide (NMMO) and using a dry-jet wet spinning process. The manufacturing process of lyocell fibers is simpler and more environmentally friendly than that of viscose fibers, has excellent physical and mechanical properties, and good dimensional stability, so it is favored by consumers. Patent Document 3 discloses the production of lyocell fibers with a temperature-regulating function by directly adding a semi-refined paraffin mixture, which is a phase change material for realizing the temperature-regulating function, to the spinning slurry of lyocell fibers. However, the phase change material in the lyocell fibers is easily lost from the lyocell fibers, and the temperature-regulating function of the fibers is not maintained for a long time.

Prior Art Documents

Patent Document

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] The problem to be solved by the present invention is to provide a lyocell fiber capable of maintaining a temperature control function for a long period and absorbing formalin, and a method for producing the same.

Means for Solving the Problems

[0008] In view of the above problems, the present inventors have conducted repeated studies and found that the temperature control function of a lyocell fiber containing cellulose, specific microcapsules having a core-shell structure, and a formalin scavenger can be maintained for a long period. The present invention has been completed based on these findings.

[0009] The present invention relates to a lyocell fiber containing cellulose, microcapsules having a core-shell structure, and a formalin scavenger, wherein the microcapsules are crosslinked with the cellulose and the formalin scavenger, the core of the microcapsules contains a phase change material and a nanonucleating agent, the shell of the microcapsules contains a melamine-modified urea formaldehyde resin prepolymer See, the particle size of the nanozinc oxide particles is in the range of 15 to 50 nm. relating to lyocell fibers.

[0010] Furthermore, the present invention relates to a method for preparing a spinning dope by mixing cellulose pulp, N-methylmorpholine-N-oxide, microcapsules having a coacel structure, and a formaldehyde scavenger, and performing post-treatment, a spinning step of spinning the spinning dope obtained through the spinning dope preparation step, and, a microwave treatment step of subjecting the yarn obtained through the spinning step to a microwave treatment step. See The microcapsule is crosslinked with the cellulose and the amide compound. The core of the microcapsule contains a phase change material and a nanonucleating agent. The shell of the microcapsule contains a melamine-modified urea formaldehyde resin prepolymer and nanozinc oxide particles. The particle size of the nanozinc oxide particles is in the range of 15 to 50 nm It relates to a method for producing lyocell fibers.

[0011] The method for producing lyocell fibers of the present invention further includes a microcapsule production step of producing the microcapsules having the coacel structure, The microcapsule production step includes: an emulsion preparation step of mixing a phase change material, a nano-nucleating agent, an emulsifier, and water to obtain an emulsion for the capsule core, a prepolymer preparation step of mixing glutaraldehyde, formaldehyde, melamine, urea, and water to perform a polycondensation reaction to obtain a melamine-modified urea formaldehyde resin prepolymer, and, It is preferable to further include a crosslinking reaction step of subjecting the emulsion for the capsule core obtained through the emulsion preparation step, the melamine-modified urea formaldehyde resin prepolymer obtained through the prepolymer preparation step, and zinc oxide nanoparticles to a crosslinking reaction.

Advantages of the Invention

[0012] The lyocell fibers of the present invention provide lyocell fibers capable of maintaining a temperature regulation function for a long period of time and absorbing formaldehyde. Furthermore, the method for producing lyocell fibers of the present invention provides the method for producing the lyocell fibers.

[0013] The method for manufacturing the lyocell fiber of the present invention can improve the stability of the microcapsules in the temperature-controlled lyocell fiber, has a short production process, does not require the use of strong alkalis or strong acids at all, is environmentally friendly, and is pollution-free.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0015] The present invention will be described in more detail. Note that "~" in the numerical range represents "from... to..." and includes both end values unless otherwise specified. Also, when a numerical range is indicated, the upper limit value and the lower limit value can be appropriately combined, and the numerical range thus obtained is also considered to be disclosed. Furthermore, in the description of the drawings, the same elements are denoted by the same reference numerals, and duplicate descriptions are omitted. Also, the dimensional ratios in the drawings are exaggerated for the convenience of explanation and may be different from the actual ratios.

[0016] <Cellulose> The lyocell fiber of the present invention contains cellulose. Cellulose constitutes the matrix of the lyocell fiber of the present invention.

[0017] <Microcapsules> The lyocell fiber of the present invention contains microcapsules having a coacervate structure. For example, in the lyocell fiber as an embodiment of the present invention shown in FIG. 1, the microcapsule 1 is crosslinked with the lyocell fiber matrix 2 and the formaldehyde scavenger 3. The microcapsule 1 has a function of storing energy and controlling temperature. The microcapsule 1 is composed of a core 4 of the microcapsule and a shell 5 of the microcapsule, as shown in FIG. 2 for example.

[0018] (Core of the microcapsule) The core of the macro capsule contains a phase change material and a nano nucleating agent. The phase change material preferably contains at least one selected from the group consisting of paraffin, n-octadecane, n-nonadecane, and n-eicosane, and more preferably is paraffin, n-octadecane, n-nonadecane, or n-eicosane. The nano nucleating agent preferably contains at least one selected from the group consisting of nano zinc oxide, nano titanium dioxide, nano calcium carbonate, and nano silica, and more preferably contains nano zinc oxide. The particle size of the nano nucleating agent is preferably in the range of 15 to 50 nm, and more preferably in the range of 25 to 38 nm. The mass ratio of the content of the nano nucleating agent to the phase change material is preferably in the range of 0.2 to 0.3:10, and more preferably in the range of 0.25 to 0.28:10.

[0019] In the present invention, the nano nucleating agent can promote crystallization as a crystal nucleus, reduce the degree of supercooling during the phase change process of the phase change material, and improve the efficiency of energy storage and temperature regulation of the phase change material.

[0020] (Cell of the microcapsule) The cell of the microcapsule contains a melamine-modified urea formaldehyde resin prepolymer. It is preferable that the cell of the microcapsule further contains nano zinc oxide particles. The particle size of the nano zinc oxide is preferably in the range of 15 to 50 nm, and more preferably in the range of 20 to 35 nm. The mass ratio of the nano zinc oxide particles to the melamine-modified urea formaldehyde resin prepolymer in the cell of the microcapsule is preferably in the range of 0.1 to 0.3:1, and more preferably in the range of 0.16 to 0.25:1.

[0021] In the present invention, by adding nano zinc oxide to the cell of the microcapsule, an antibacterial function can be imparted to the temperature-regulating lyocell fiber.

[0022] <Formaldehyde scavenger> The formaldehyde scavenger of the present invention is preferably an amide compound. It is preferable that the mass ratio of the content of the formaldehyde scavenger to that of the microcapsules is in the range of 1 to 1.5:20. The mass ratio of the contents of cellulose, microcapsules, and formaldehyde scavenger in the lyocell fiber is preferably in the range of 100:49.8 to 99.7:2.5 to 5, and more preferably in the range of 100:67.5 to 89.2:3.3 to 4.5.

[0023] In the present invention, the formaldehyde scavenger plays a role in absorbing formaldehyde generated by formaldehyde in the cells of microcapsules, melamine, etc. By adding the formaldehyde scavenger, more microcapsules can be added to the lyocell fiber, and a better temperature control effect can be achieved.

[0024] <Method for producing lyocell fiber> (Spinning dope preparation step) The method for producing lyocell fiber of the present invention includes a spinning dope preparation step. In the spinning dope preparation step, cellulose pulp, N-methylmorpholine-N-oxide, microcapsules having a coacervate structure, and a formaldehyde scavenger are mixed and post-treated. The average degree of polymerization of the cellulose pulp in the spinning dope preparation step is preferably in the range of 600 to 800, and more preferably in the range of 680 to 750. The content of α-cellulose contained in the cellulose pulp is preferably in the range of 92 to 99% by mass, and more preferably in the range of 96% to 98% by mass. It is preferable that the content of α-cellulose contained in the cellulose pulp is 92 to 99% by mass. The content ratio of the microcapsules, the formaldehyde scavenger, and the α-cellulose contained in the cellulose pulp is preferably in the range of 50.6 to 101.8:2.5 to 5:100 by mass ratio, and more preferably in the range of 68.2 to 91.0:3.4 to 4.55:100. The content of α-cellulose in the spinning dope is preferably in the range of 10 to 20% by mass, more preferably in the range of 12 to 16% by mass. The N-methylmorpholine-N-oxide is preferably provided in the form of an aqueous solution of N-methylmorpholine-N-oxide. The concentration of the aqueous solution of N-methylmorpholine-N-oxide is preferably in the range of 80 to 87% by mass, more preferably in the range of 82 to 85% by mass.

[0025] The post-treatment preferably includes at least one selected from the group consisting of heating, vacuum pumping, dehydration, dissolution, homogenization, defoaming, and filtration steps, and more preferably, the heating, vacuum pumping, dehydration, dissolution, homogenization, defoaming, and filtration steps are performed in sequence. There are no particular limitations on the methods of heating, vacuum pumping, dehydration, dissolution, homogenization, defoaming, and filtration, and known methods in the technical field may be adopted.

[0026] (Spinning process) The method for producing lyocell fibers of the present invention includes a spinning process. In the spinning process, the spinning dope obtained through the spinning dope preparation process is spun. The spinning speed in the spinning process is preferably in the range of 25 to 45 m / min, more preferably in the range of 32 to 40 m / min. The concentration of the coagulation bath used in the spinning process is preferably in the range of 10 to 20% by mass, more preferably in the range of 13 to 18% by mass, and the temperature of the coagulation bath is preferably in the range of 15 to 25 °C, more preferably in the range of 18 to 22 °C.

[0027] After the spinning process and before the microwave treatment process, it is preferably further included to perform the steps of washing the product obtained through the spinning process with water, bleaching, and oil coating in sequence. The water used for the water washing is preferably deionized water. The water temperature for the water washing is preferably in the range of 20 to 25 °C, more preferably in the range of 38 to 40 °C. The bleaching is preferably bleaching with an aqueous solution of hydrogen peroxide. The concentration of the aqueous solution of hydrogen peroxide is preferably in the range of 1.0 to 2.0 g / L, more preferably in the range of 1.5 to 1.8 g / L. The pH value of the aqueous solution of hydrogen peroxide is preferably in the range of 8.5 to 10, more preferably in the range of 9 to 9.5. The temperature of the aqueous solution of hydrogen peroxide is preferably in the range of 30 to 45 °C, more preferably in the range of 36 to 41 °C. The temperature of the oil bath used for the oil application is preferably in the range of 50 to 80 °C, more preferably in the range of 65 to 72 °C. The pH value of the oil bath is preferably in the range of 6.0 to 9.0, more preferably in the range of 7.0 to 8.0. The oil used for the oil application is not particularly limited, and known ones in the technical field may be used. The concentration of the oil in the oil bath is preferably in the range of 2.5 to 6.0 g / L, more preferably in the range of 3.5 to 5.0 g / L.

[0028] (Microwave treatment step) The method for producing lyocell fiber of the present invention includes a microwave treatment step. In the microwave treatment step, the yarn obtained through the spinning step is subjected to the microwave treatment step. The frequency of the microwave irradiated in the microwave treatment step is preferably in the range of 1560 to 1800 MHz, more preferably in the range of 1650 to 1720 MHz. The treatment time of the microwave treatment step is preferably in the range of 20 to 36 minutes, more preferably in the range of 26 to 33 minutes.

[0029] The microwave treatment step polycondenses the hydroxymethyl groups in the cells of the microcapsules with the formaldehyde scavenger and the hydroxyl groups in the cellulose to form methylene bonds, and forms hydrogen bonds between the unreacted hydroxymethyl groups and amino groups in the cells of the microcapsules, that is, the hydroxymethyl groups and amino groups in the melamine-modified urea formaldehyde resin prepolymer, and the hydroxyl groups in the cellulose, thereby improving the stability of the microcapsules, reducing the loss of the microcapsules due to washing and daily use, and absorbing formaldehyde generated from the cell material of the microcapsules. Here, it is preferable that the frequency of the microwave irradiated in the microwave treatment step is in the range of 1560 to 1800 MHz. When the frequency of the microwave is in the above range, it is prevented that the bonding of the functional groups between the microcapsules, the formaldehyde scavenger and the cellulose cannot be formed or is destroyed, and the stability of the microcapsules is improved.

[0030] In the present invention, the microwave treatment also serves to dry. The moisture content of the cellulose fiber subjected to the microwave treatment is preferably 8.5 to 11.6% by mass, more preferably 9.7 to 10.2% by mass.

[0031] <Manufacturing process of microcapsules> (Emulsion preparation step) The emulsion preparation step of the present invention is a capsule core material preparation step of mixing the melted phase change material and the nanonucleating agent to obtain a capsule core material, and preferably further includes a capsule core material emulsion preparation step of mixing the capsule core material, an emulsifier, and water to obtain a capsule core material emulsion.

[0032] The phase change material preferably includes at least one selected from the group consisting of paraffin, n-octadecane, n-nonadecane, and n-eicosane, and more preferably includes n-octadecane or n-eicosane. The nano nucleating agent preferably includes at least one selected from the group consisting of zinc oxide nanoparticles, titanium dioxide nanoparticles, calcium carbonate nanoparticles, and silica nanoparticles, and more preferably includes zinc oxide nanoparticles. The particle size of the nano nucleating agent is preferably in the range of 15 to 50 nm, and more preferably in the range of 25 to 38 nm. The emulsifier preferably includes at least one selected from the group consisting of polysorbate-80, sodium dodecyl sulfate (SDS), span-80, and sodium styrene maleate, and more preferably is polysorbate-80 or span-80. When the emulsifier contains two or more of the above-listed substances, the mass mixing ratio of the specific substances is not particularly limited, and any mixing ratio can be adopted. The water is preferably distilled water.

[0033] The melting temperature is preferably in the range of 40 to 50 °C, and more preferably in the range of 42 to 48 °C. The melting time is not particularly limited as long as the phase change material can be melted. In the present invention, the capsule core material preparation step is preferably carried out under stirring conditions. The stirring speed is preferably in the range of 600 to 850 r / min, and more preferably in the range of 680 to 800 r / min. The stirring time is not particularly limited as long as the mixture can be uniformly mixed. In the present invention, the dispersion means of the dispersion liquid is not particularly limited as long as it can be uniformly dispersed.

[0034] The content of the capsule core material in the capsule core material emulsion is preferably in the range of 30 to 40% by mass, and more preferably in the range of 32.5 to 36.8% by mass. The content of the emulsifier in the capsule core material emulsion is preferably in the range of 2.5% to 4% by mass, and more preferably in the range of 3.2 to 3.75% by mass.

[0035] The temperature of the step of preparing the emulsion of the capsule core material is preferably in the range of 40 to 50 °C, more preferably in the range of 42 to 46 °C. The step of preparing the emulsion of the capsule core material is preferably carried out under stirring conditions. The stirring speed is preferably in the range of 1800 to 2300 r / min, more preferably in the range of 1980 to 2150 r / min. In the step of preparing the emulsion of the capsule core material, the particle size of the emulsion droplets is detected. The particle size of the emulsion droplets is preferably in the range of D90 ≤ 1.055 μm, more preferably in the range of 0.892 μm ≤ D90 ≤ 0.998 μm. The stirring time is not particularly limited as long as the particle size of the emulsion droplets can reach the above range.

[0036] The particle size of the above emulsion droplets is detected by a laser particle size distribution analyzer.

[0037] (Prepolymer Preparation Step) In the prepolymer preparation step of the present invention, glutaraldehyde, formaldehyde, melamine, urea, and water are mixed to carry out a polycondensation reaction to obtain a melamine-modified urea formaldehyde resin prepolymer. The reaction temperature of the polycondensation reaction in the prepolymer preparation step is preferably in the range of 40 to 50 °C.

[0038] The formaldehyde is preferably provided in the form of an aqueous formaldehyde solution. In the present invention, the concentration of the aqueous formaldehyde solution is preferably 35 to 39% by mass, more preferably 37% by mass. The mass ratio of the content of the glutaraldehyde to the content of the formaldehyde is preferably in the range of 1:1 to 3, more preferably in the range of 1:1.8 to 2.5. The mass ratio of the content of the melamine to the content of the urea is preferably in the range of 0.05 to 0.15:1, more preferably in the range of 0.08 to 0.12:1. In the present invention, the mass ratio of the total mass of the glutaraldehyde and the formaldehyde to the total mass of the melamine and the urea is preferably in the range of 2 to 4:1, more preferably in the range of 2.5 to 3:1.

[0039] The mixing is not particularly limited as long as it can be uniformly mixed. In the present invention, it is more preferable to include a step of adjusting the pH value of the mixture to a range of 7.5 to 8.5, more preferably 8, before the polycondensation reaction. The pH adjuster for adjusting the pH value of the mixture preferably contains triethanolamine or sodium hydroxide, and more preferably triethanolamine. The dosage of the pH adjuster is not particularly limited as long as it can be adjusted to the desired pH value.

[0040] The polycondensation reaction preferably involves stirring, and the rotation speed of the stirring is preferably in the range of 200 to 400 r / min, more preferably in the range of 260 to 320 r / min. In the present invention, the temperature of the polycondensation reaction is preferably in the range of 60 to 90 °C, more preferably in the range of 70 to 80 °C. In the present invention, the time of the polycondensation reaction is not particularly limited as long as the reaction system becomes a colorless and transparent solution.

[0041] (Crosslinking reaction step) In the crosslinking reaction step of the present invention, the emulsion for the capsule core obtained through the emulsion preparation step, the melamine-modified urea formaldehyde resin prepolymer obtained through the prepolymer preparation step, and zinc oxide nanoparticles are subjected to a crosslinking reaction to obtain the microcapsule dispersion. The reaction temperature of the crosslinking reaction step is preferably in the range of 65 to 75 °C, more preferably in the range of 68 to 72 °C. The reaction time of the crosslinking reaction step is in the range of 150 to 240 minutes, more preferably in the range of 180 to 200 minutes.

[0042] The crosslinking reaction step A capsule cell material dispersion preparation step of dispersing zinc oxide nanoparticles in the melamine-modified urea formaldehyde resin prepolymer to obtain a capsule cell material dispersion, and Preferably, it further includes a mixing step of mixing the capsule cell material dispersion and the capsule core material emulsion.

[0043] In the step of preparing the capsule cell material dispersion liquid, the mass ratio of the nanozinc oxide to the total mass of melamine and urea is preferably in the range of 0.1 to 0.3:1, more preferably in the range of 0.16 to 0.25:1. In the step of preparing the capsule cell material dispersion liquid, the dispersion temperature is preferably in the range of 40 to 50 °C, more preferably in the range of 43 to 47 °C. The dispersion method is not particularly limited as long as it can achieve uniform dispersion.

[0044] In the present invention, the nanozinc oxide in the capsule cell material dispersion liquid imparts good antibacterial performance to the lyocell fiber.

[0045] In the mixing step, the mass ratio of the capsule core material to the melamine-modified urea formaldehyde resin prepolymer is preferably in the range of 1.5 to 2.3:1, more preferably in the range of 1.8 to 2.1:1. In the present invention, the mixing temperature of the mixing step is preferably in the range of 40 to 50 °C, more preferably in the range of 42 to 48 °C. In the present invention, the mixing step is preferably carried out under stirring conditions. The rotation speed of the stirring is preferably in the range of 1800 to 2300 r / min, more preferably in the range of 1980 to 2150 r / min. The stirring time is not particularly limited as long as the mixture can be uniformly mixed.

[0046] In the present invention, after the cross-linking reaction step, it is preferable to perform heat evaporation to remove a part of water. The content of the microcapsules in the microcapsule dispersion liquid after the heat evaporation is preferably in the range of 35 to 45% by mass, more preferably in the range of 38 to 42% by mass. Regarding the conditions of the heat evaporation, there is no particular limitation as long as the content range of the microcapsules limited above can be achieved.

[0047] In the present invention, after the cross-linking reaction step, it is preferably further included a solid-liquid separation step of separating the mixture obtained through the cross-linking reaction step to obtain microcapsules. The means of the solid-liquid separation is not particularly limited as long as it can achieve solid-liquid separation.

[0048] In the present invention, it is preferable to further include an activation step of activating the cellulose pulp before the spinning dope preparation step. The activation step is preferably carried out by cellulase. The pH value of the activation step is preferably in the range of 4 to 6, more preferably in the range of 5 to 5.5. The activation temperature of the activation step is preferably in the range of 40 to 55 °C, more preferably in the range of 45 to 50 °C. The activation time of the activation step is preferably in the range of 30 to 60 minutes, more preferably in the range of 40 to 50 minutes. The mass ratio of the cellulase to the dry weight of the cellulose pulp is preferably 500 to 6000 g:1000 kg, more preferably 2000 to 4000 g:1000 kg.

[0049] In the present invention, after the activation step, it is preferable to further include a pressing step of adjusting the pH value of the product obtained through the activation step to a range of 10 to 12 and then pressing. The pH adjuster used to adjust the pH value is not particularly limited as long as it can achieve the desired pH value. After the pressing step, the water content of the cellulose pulp is preferably 30 to 60% by mass, more preferably 40 to 50% by mass.

[0050] In the present invention, in order to simplify the operation procedure, it is preferable to directly mix the microcapsule dispersion obtained through the cross-linking reaction step, a formaldehyde catcher, the cellulose pulp, and an aqueous solution of N-methylmorpholine-N-oxide.

[0051] The phase change temperature-adjustable lyocell fiber of the present invention can be applied to clothing or bedding.

Example

[0052] Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

[0053] [Example 1] The paraffin was melted at 40 °C and mixed with zinc oxide nanoparticles with a particle size of 50 nm at a rotation speed of 600 r / min to obtain a capsule core material. Here, the mass ratio of paraffin to zinc oxide nanoparticles was 0.2:10. Sodium styrene maleate was dispersed in distilled water to obtain an emulsifier dispersion. The capsule core material and the emulsifier dispersion were mixed at a temperature of 40 °C and a rotation speed of 1800 r / min to obtain a capsule core material emulsion. In the capsule core material emulsion, the content of the capsule core material was 30% by mass, the content of sodium styrene maleate was 2.5% by mass, and the particle size D90 = 0.892 μm.

[0054] Glutaraldehyde, an aqueous formaldehyde solution with a concentration of 37% by mass, melamine, and urea were mixed, and then the pH value of the mixture was adjusted to 7.5 using triethanolamine. At a temperature of 60 °C and a rotation speed of 400 r / min, the polycondensation reaction was continued until a colorless transparent solution was obtained to obtain a melamine-modified urea formaldehyde resin prepolymer solution. Here, the mass ratio of glutaraldehyde to formaldehyde in the aqueous formaldehyde solution was 1:1, the mass ratio of melamine to urea was 0.05:1, and the ratio of the total mass of glutaraldehyde and formaldehyde in the aqueous formaldehyde solution to the total mass of melamine and urea was 4:1 by mass.

[0055] Zinc oxide nanoparticles with a particle size of 50 nm were dispersed in a melamine-modified urea formaldehyde resin prepolymer solution maintained at a temperature of 40 °C to obtain a capsule cell material dispersion. Here, the ratio of zinc oxide nanoparticles to the total mass of melamine and urea was 0.1:1 by mass.

[0056] The emulsion of the capsule core material and the dispersion of the capsule shell material were mixed at a temperature of 40°C and a rotation speed of 1800 r / min, and then a cross-linking reaction was carried out at 65°C for 240 minutes to obtain a microcapsule dispersion. Here, the mass ratio of the capsule core material to the melamine-modified urea formaldehyde resin prepolymer was 1.5:1. Further, the microcapsule dispersion was heated and evaporated to obtain a microcapsule dispersion with a concentration of 35% by mass.

[0057] Cellulose pulp with an average degree of polymerization of 600 and an α-cellulose content of 92% by mass was activated with cellulase for 60 minutes under the conditions of a pH value of 4 and a temperature of 40°C. The mass ratio of cellulase to the dry weight of cellulose pulp was 500 g:1000 kg. After activation, the pH value was adjusted to 10, and pressing was performed to obtain cellulose pulp with a water content of 30% by mass.

[0058] The microcapsule dispersion, an amide compound (RIKEN RESIN CHACHERC-40, manufactured by Miki Riken Co., Ltd., Japan), the cellulose pulp after pressing, and an aqueous solution of N-methylmorpholine-N-oxide with a concentration of 80% by mass were mixed, and then heating, vacuum pumping, dehydration, dissolution, homogenization, defoaming, and filtration were carried out in sequence to obtain a spinning dope. Here, the mass ratio of microcapsules to the amide compound to α-cellulose in the cellulose pulp was 50.6:2.53:100, and the content of α-cellulose in the spinning dope was 10% by mass.

[0059] After spinning with the above spinning dope, washing with water (deionized water, 20°C), bleaching (an aqueous hydrogen peroxide solution with a concentration of 1.0 g / L, a pH value of 8.5, and a temperature of 45°C), oil coating (the concentration of the oil bath was 2.5 g / L, the temperature was 50°C, and the pH value was 6.0) were carried out in sequence, and then microwave treatment was carried out at 1560 MHz for 36 minutes to obtain lyocell fibers. Here, the spinning speed was 45 m / min, the concentration of the coagulation bath during spinning was 10%, and the temperature of the coagulation bath was 15°C. The water content of the obtained lyocell fibers was 8.5% by mass, and the specification was 2.22 dtex×3 mm.

[0060] [Example 2] n-octadecane was melted at 42 °C and mixed with zinc oxide nanoparticles with a particle size of 38 nm at a rotation speed of 680 r / min to obtain a capsule core material. Here, the mass ratio of paraffin to zinc oxide nanoparticles was 0.25:1. Span-80 was dispersed in distilled water to obtain an emulsifier dispersion. The capsule core material and the emulsifier dispersion were mixed at a temperature of 42 °C and a rotation speed of 1980 r / min to obtain a capsule core material emulsion. The content of the capsule core material in the capsule core material emulsion was 32.5% by mass. The content of Span-80 was 3.2% by mass and the particle size D90 = 0.952 μm.

[0061] Glutaraldehyde, an aqueous formaldehyde solution with a concentration of 37%, melamine, and urea were mixed. Next, the pH value was adjusted to 8.0 using triethanolamine, and a polycondensation reaction was carried out at a temperature of 70 °C and a rotation speed of 320 r / min until the solution became transparent to obtain a melamine-modified urea formaldehyde resin prepolymer solution. The mass ratio of glutaraldehyde to formaldehyde in the aqueous formaldehyde solution was 1:1.8, the mass ratio of melamine to urea was 0.08:1, and the ratio of the total mass of glutaraldehyde and formaldehyde in the aqueous formaldehyde solution to the total mass of melamine and urea was 3:1 by mass.

[0062] Zinc oxide nanoparticles with a particle size of 35 nm were dispersed in a melamine-modified urea formaldehyde resin prepolymer solution at a temperature of 43 °C to obtain a capsule cell material dispersion. Here, the ratio of zinc oxide nanoparticles to the total mass of melamine and urea was 0.16:1 by mass.

[0063] The emulsion of the capsule core material and the dispersion of the capsule cell material were mixed at a temperature of 42 °C and a rotation speed of 1980 r / min. Then, a cross-linking reaction was carried out at 68 °C for 200 minutes to obtain a microcapsule dispersion. Here, the mass ratio of the capsule core material to the melamine-modified urea formaldehyde resin prepolymer was 1.8:1. Further, the microcapsule dispersion was heated and evaporated to obtain a microcapsule dispersion with a concentration of 38%.

[0064] Cellulose pulp with an average degree of polymerization of 680 and an α-cellulose content of 96% by mass was activated with cellulase for 50 minutes under the conditions of a pH value of 5 and a temperature of 45 °C. The mass ratio of the dry weight of cellulase to cellulose pulp was 2000 g:1000 kg. After activation, the pH value was adjusted to 10.5, and pressing was performed to obtain cellulose pulp with a moisture content of 40% by mass.

[0065] The microcapsule dispersion, an amide compound (RIKEN RESIN CHACHERC-40, manufactured by Miki Riken Co., Ltd., Japan), the cellulose pulp after pressing, and an aqueous solution of N-methylmorpholine-N-oxide with a concentration of 82% were mixed. Then, heating, vacuum pumping, dehydration, dissolution, homogenization, defoaming, and filtration were carried out in sequence to obtain a spinning dope. Here, the mass ratio of the microcapsules, the amide compound, and the α-cellulose in the cellulose pulp was 68.5:3.4:100, and the content of α-cellulose in the spinning dope was 12% by mass.

[0066] After spinning with the above spinning dope, washing with water (deionized water, 30 °C), bleaching (an aqueous hydrogen peroxide solution with a concentration of 1.5 g / L, a pH value of 9.0, and a temperature of 41 °C), and oil coating (the concentration of the oil bath was 3.5 g / L, the temperature was 70 °C, and the pH value was 7.0) were carried out in sequence. Then, microwave treatment was carried out at 1650 MHz for 33 minutes to obtain lyocell fibers. Here, the spinning speed was 40 m / min, the concentration of the coagulation bath during spinning was 13% by mass, and the temperature of the coagulation bath was 18 °C. The moisture content of the obtained lyocell fibers was 9.7, and the specification was 3.33 dtex × 42 mm.

[0067] [Example 3] n-Nonadecane was melted at 48 °C and mixed with zinc oxide nanoparticles with a particle size of 25 nm at a rotational speed of 800 r / min to obtain a capsule core material. Here, the mass ratio of paraffin to zinc oxide nanoparticles was 0.28:1. Sodium lauryl sulfate was dispersed in distilled water to obtain an emulsifier dispersion. The capsule core material and the emulsifier dispersion were mixed at a temperature of 46 °C and a rotational speed of 21150 r / min to obtain a capsule core material emulsion. The content of the capsule core material in the capsule core material emulsion was 36.8%. The content of sodium lauryl sulfate was 3.75%, and the particle size D90 = 0.998 μm.

[0068] Glutaraldehyde, an aqueous formaldehyde solution with a concentration of 37% by mass, melamine, and urea were mixed, and then the pH value was adjusted to 8.0 using sodium hydroxide. A polycondensation reaction was carried out at a temperature of 80 °C and a rotational speed of 260 r / min until the solution became transparent to obtain a melamine-modified urea formaldehyde resin prepolymer solution. The mass ratio of glutaraldehyde to formaldehyde in the aqueous formaldehyde solution was 1:2.5, the mass ratio of melamine to urea was 0.12:1, and the ratio of the total mass of glutaraldehyde and formaldehyde in the aqueous formaldehyde solution to the total mass of melamine and urea was 2.5:1 by mass.

[0069] Zinc oxide nanoparticles with a particle size of 20 nm were dispersed in a melamine-modified urea formaldehyde resin prepolymer solution at a temperature of 47 °C to obtain a capsule cell material dispersion. Here, the ratio of zinc oxide nanoparticles to the total mass of melamine and urea was 0.25:1 by mass.

[0070] The emulsion of the capsule core material and the dispersion of the capsule shell material were mixed at a temperature of 48 °C and a rotation speed of 2150 r / min, and then a cross-linking reaction was carried out at 72 °C for 180 minutes to obtain a microcapsule dispersion. Here, the mass ratio of the capsule core material to the melamine-modified urea formaldehyde resin prepolymer was 2.1:1. Further, the microcapsule dispersion was heated and evaporated to obtain a microcapsule dispersion with a concentration of 42% by mass.

[0071] Cellulose pulp with an average degree of polymerization of 750 and an α-cellulose content of 98% was activated by cellulase for 40 minutes under the conditions of a pH value of 5.5 and a temperature of 50 °C. The mass ratio of cellulase to the dry weight of cellulose pulp was 4000 g:1000 kg. After activation, the pH value was adjusted to 11.5, and pressing was performed to obtain cellulose pulp with a water content of 50% by weight.

[0072] The microcapsule dispersion, an amide compound (RIKEN RESIN CHACHERC-40, manufactured by Miki Riken Co., Ltd., Japan), the pressed cellulose pulp, and an aqueous solution of N-methylmorpholine-N-oxide with a concentration of 85% were mixed, and then heating, vacuum pumping, dehydration, dissolution, homogenization, defoaming, and filtration were carried out in sequence to obtain a spinning dope. Here, the mass ratio of microcapsules, the amide compound, and α-cellulose in the cellulose pulp was 91.0:4.55:100, and the content of α-cellulose in the spinning dope was 16%.

[0073] After spinning with the above spinning dope, washing with water (deionized water, 40 °C), bleaching (an aqueous hydrogen peroxide solution with a concentration of 1.8 g / L, a pH value of 9.5, and a temperature of 36 °C), oil coating (the concentration of the oil bath was 5.0 g / L, the temperature was 65 °C, and the pH value was 8.0) were carried out in sequence, and then microwave treatment was carried out at 1720 MHz for 26 minutes to obtain lyocell fibers. Here, the spinning speed was 32 m / min, the concentration of the coagulation bath during spinning was 18% by mass, and the temperature of the coagulation bath was 22 °C. The water content of the obtained lyocell fibers was 10.2% by mass, and the specification was 5.56 dtex×60 mm.

[0074] [Example 4] n-Eicosane was melted at 50 °C and mixed with zinc oxide nanoparticles with a particle size of 15 nm at a rotation speed of 850 r / min to obtain a capsule core material. Here, the mass ratio of paraffin to zinc oxide nanoparticles was 0.3:1. Polysorbate-80 was dispersed in distilled water to obtain an emulsifier dispersion. The capsule core material and the emulsifier dispersion were mixed at a temperature of 50 °C and a rotation speed of 2300 r / min to obtain a capsule core material emulsion. The content of the capsule core material in the capsule core material emulsion was 40% by mass. The content of polysorbate-80 was 4% by mass and the particle size D90 = 1.055 μm.

[0075] Glutaraldehyde, an aqueous formaldehyde solution with a concentration of 37%, melamine, and urea were mixed, and then the pH value was adjusted to 8.5 using sodium hydroxide. A polycondensation reaction was carried out at a temperature of 90 °C and a rotation speed of 200 r / min until the solution became transparent to obtain a melamine-modified urea formaldehyde resin prepolymer solution. The mass ratio of glutaraldehyde to formaldehyde in the aqueous formaldehyde solution was 1:3, the mass ratio of melamine to urea was 0.15:1, and the ratio of the total mass of glutaraldehyde and formaldehyde in the aqueous formaldehyde solution to the total mass of melamine and urea was 2:1 by mass.

[0076] Zinc oxide nanoparticles with a particle size of 15 nm were dispersed in a melamine-modified urea formaldehyde resin prepolymer solution at a temperature of 50 °C to obtain a capsule cell material dispersion. Here, the ratio of zinc oxide nanoparticles to the total mass of melamine and urea was 0.3:1 by mass.

[0077] The emulsion of the capsule core material and the dispersion of the capsule shell material were mixed at a temperature of 50 °C and a rotation speed of 2300 r / min, and then a cross-linking reaction was carried out at 75 °C for 150 minutes to obtain a microcapsule dispersion. Here, the mass ratio of the capsule core material to the melamine-modified urea formaldehyde resin prepolymer was 2.3:1. Further, the microcapsule dispersion was heated and evaporated to obtain a microcapsule dispersion with a concentration of 45% by mass.

[0078] Cellulose pulp with an average degree of polymerization of 800 and an α-cellulose content of 99% was activated by cellulase for 30 minutes under the conditions of a pH value of 6 and a temperature of 55 °C. The mass ratio of the dry weight of cellulase to cellulose pulp was 6000 g:1000 kg. After activation, the pH value was adjusted to 12 and pressed to obtain cellulose pulp with a water content of 60% by mass.

[0079] The microcapsule dispersion, an amide compound (RIKEN RESIN CHACHERC-40, manufactured by Miki Riken Co., Ltd., Japan), the pressed cellulose pulp, and an aqueous solution of N-methylmorpholine-N-oxide with a concentration of 87% by mass were mixed, and then heating, vacuuming, dehydration, dissolution, homogenization, defoaming, and filtration were carried out in sequence to obtain a spinning dope. Here, the mass ratio of microcapsules, the amide compound, and α-cellulose in the cellulose pulp was 101.8:5.1:100, and the content of α-cellulose in the spinning dope was 20% by mass.

[0080] After spinning with the above spinning dope, washing with water (deionized water, 50 °C), bleaching (an aqueous hydrogen peroxide solution with a concentration of 2.0 g / L, a pH value of 10.0, and a temperature of 30 °C), oil coating (the concentration of the oil bath was 6.0 g / L, the temperature was 65 °C, and the pH value was 9.0) were carried out in sequence, and then microwave treatment was carried out at 1800 MHz for 20 minutes to obtain lyocell fibers. Here, the spinning speed was 25 m / min, the concentration of the coagulation bath during spinning was 20% by mass, and the temperature of the coagulation bath was 25 °C. The water content of the obtained lyocell fibers was 11.6%, and the specification was 6.67 dtex×60 mm.

[0081] In the examples and comparative examples, various physical properties were measured or calculated as follows.

[0082] According to GB / T14337-2008 "Test Method for Tensile Properties of Chemical Fibers - Staple Fibers", the dry breaking strength, wet breaking strength, and lateral swelling rate of the lyocell fibers produced in Examples 1 to 4 were measured. The results are shown in Table 1.

[0083] According to the oscillation method in Part 3 of GB / T20944.3~2008 "Textiles - Evaluation of Antibacterial Properties", the inhibition rates of the lyocell fibers produced in Examples 1 to 4 against Staphylococcus aureus, Escherichia coli, and Candida albicans were detected. The results are shown in Table 1.

[0084] According to GB / T19466.3-2004 "Plastics - Differential Scanning Calorimetry (DSC) - Part 3: Measurement of Melting and Crystallization Temperatures and Enthalpies", the phase change melting temperature, melting phase change enthalpy, phase change crystallization temperature, and crystallization phase change enthalpy of the lyocell fibers produced in Examples 1 to 4 were measured. The results are shown in Table 1.

[0085] Regarding the measurement method of formaldehyde, it was measured by a test for measuring the amount of free formaldehyde extracted in the liquid phase from textile products. The results are shown in Table 1.

[0086] According to the "Enforcement Regulations of the Law on the Regulation of Household Goods Containing Hazardous Substances" of the Ministry of Health and Welfare Ordinance No. 34, or JIS L1041 "Test Methods for Resin - Processed Fabrics and Knitted Fabrics", the amount of formaldehyde in the lyocell fibers produced in Examples 1 to 4 was measured. The results are shown in Table 1.

[0087] According to the washing method in Appendix C4 of the quasi-FZ / T73023-2006 "Simple Washing Conditions and Programs", the lyocell fibers produced in Examples 1 to 4 were washed 50 times, and then performance tests were carried out. The results are shown in Table 2.

[0088]

Table 1

[0089] Table 1 shows the performance parameters of the lyocell fibers produced in Examples 1 to 4. As shown in Table 1, the lyocell fibers of the present invention have good tensile properties and antibacterial properties, and also have good high-efficiency energy storage performance and temperature regulation performance. In addition, it was found that the lyocell fibers of the present invention have an absorption effect on formalin. Furthermore, it was found that the lyocell fibers of the present invention have an enthalpy value higher than 40 J / g. The greater the enthalpy value, the better the temperature regulation effect of the lyocell fibers.

[0090]

Table 2

[0091] Table 2 shows the performance parameters of the lyocell fibers produced in Examples 1 to 4 after being washed 50 times. As can be seen by comparing Table 1 and Table 2, it was found that the lyocell fibers of the present invention can maintain good tensile properties, antibacterial properties, and high-efficiency energy storage and temperature regulation properties even after being washed 50 times.

[0092] The present invention has been described in detail based on the above embodiments, but these are only a part of the embodiments of the present invention and not all of the embodiments. It should also be understood that other embodiments can be obtained based on these embodiments, and all of these embodiments belong to the protection scope of the present invention.

Explanation of Signs

[0093] 1...Microcapsule, 2...Lyocell fiber matrix, 3...Formalin scavenger, 4...Core of microcapsule, 5...Cell of microcapsule.

Claims

1. A lyocell fiber containing cellulose, microcapsules having a core-shell structure, and an amide compound, wherein the microcapsules are crosslinked with the cellulose and the amide compound, the core of the microcapsules contains a phase change material and a nano-nucleating agent, the shell of the microcapsules contains a melamine-modified urea formaldehyde resin prepolymer and zinc oxide nanoparticles, and the particle size of the zinc oxide nanoparticles ranges from 15 to 50 nm.

2. The lyocell fiber according to claim 1, wherein the mass ratio of the contents of the cellulose, microcapsules, and amide compound ranges from 100:49.8 to 99.7:2.5 to 5.

3. The phase change material contains at least one selected from the group consisting of paraffin, n-octadecane, n-nonadecane, and n-eicosane, the nano-nucleating agent contains at least one selected from the group consisting of zinc oxide nanoparticles, titanium dioxide nanoparticles, calcium carbonate nanoparticles, and silica nanoparticles, the particle size of the nano-nucleating agent ranges from 15 to 50 nm, and the mass ratio of the contents of the nano-nucleating agent and the phase change material ranges from 0.2 to 0.3:

10. The lyocell fiber according to claim 1 or 2.

4. The lyocell fiber according to claim 1, wherein the mass ratio of the contents of the amide compound and the microcapsules ranges from 1 to 1.5:

20.

5. The lyocell fiber according to claim 1, wherein the mass ratio of the contents of the zinc oxide nanoparticles and the melamine-modified urea formaldehyde resin prepolymer in the shell of the microcapsules ranges from 0.1 to 0.3:

1.

6. A spinning dope preparation step of mixing cellulose pulp, N-methylmorpholine-N-oxide, microcapsules having a core-shell structure, and an amide compound and performing post-treatment, a spinning step of spinning the spinning dope obtained through the spinning dope preparation step, and a microwave treatment step of subjecting the yarn obtained through the spinning step to a microwave treatment step, wherein the microcapsules are crosslinked with the cellulose and the amide compound, the core of the microcapsules contains a phase change material and a nano-nucleating agent, and the shell of the microcapsules contains a melamine-modified urea formaldehyde resin prepolymer and zinc oxide nanoparticles. A method for producing lyocell fibers, wherein the particle size of the nanozinc oxide particles is in the range of 15 to 50 nm.

7. The method for producing lyocell fibers according to claim 6, wherein the frequency of the microwave irradiated in the microwave treatment step is in the range of 1560 to 1800 MHz, and the treatment time of the microwave treatment step is in the range of 20 to 36 minutes.

8. The content of α-cellulose contained in the cellulose pulp is 92 to 99% by mass, The method for producing lyocell fibers according to claim 6, wherein the content ratio of the microcapsules, the amide compound, and the α-cellulose contained in the cellulose pulp is 50.6 to 101.8:2.5 to 5:100 by mass ratio.

9. The method further includes a microcapsule production step for producing the microcapsules having the coacervate structure, The microcapsule production step is as follows: An emulsion preparation step of mixing a phase change material, a nano-nucleating agent, an emulsifier, and water to obtain an emulsion for the capsule core, A prepolymer preparation step of mixing glutaraldehyde, formaldehyde, melamine, urea, and water to perform a polycondensation reaction to obtain a melamine-modified urea formaldehyde resin prepolymer, and The method for producing lyocell fibers according to claim 6, further including a crosslinking reaction step of crosslinking the emulsion for the capsule core obtained through the emulsion preparation step, the melamine-modified urea formaldehyde resin prepolymer obtained through the prepolymer preparation step, and nanozinc oxide.

10. The emulsion preparation step is as follows: A capsule core material preparation step of mixing the melted phase change material and the nano-nucleating agent to obtain a capsule core material, and The method for producing lyocell fibers according to claim 9, further including a capsule core material emulsion preparation step of mixing the capsule core material, an emulsifier, and water to obtain an emulsion of the capsule core material.

11. The crosslinking reaction step is as follows: A capsule cell material dispersion preparation step of dispersing nanozinc oxide in the melamine-modified urea formaldehyde resin prepolymer to obtain a capsule cell material dispersion, and The method for producing lyocell fibers according to claim 10, further including a mixing step of mixing the capsule cell material dispersion and the emulsion of the capsule core material.

12. The reaction temperature of the polycondensation reaction in the prepolymer preparation step is in the range of 40 to 50 °C, The reaction temperature of the crosslinking reaction in the crosslinking reaction step is in the range of 65 to 75 °C, and the reaction time is in the range of 150 to 240 minutes, The method for producing lyocell fiber according to claim 9.

13. The post-treatment includes at least one selected from the group consisting of heating, evacuation, dehydration, dissolution, homogenization, defoaming, and filtration steps, The method for producing lyocell fiber according to any one of claims 6 to 12.

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