JP2020094323A - Polyester-based short fibers with fine fineness - Google Patents
Polyester-based short fibers with fine fineness Download PDFInfo
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本発明は、単繊維繊度が０．５ｄｔｅｘ以下の繊度の小さい短繊維に関するものであり、特に乾式用不織布の原料として用いた場合に、工程通過性が良好で、嵩高性に優れた不織布を提供しうる細繊度ポリエステル系短繊維に関するものである。 The present invention relates to a short fiber having a single fiber fineness of 0.5 dtex or less and a small fineness, and particularly when used as a raw material for a dry-use nonwoven fabric, provides a nonwoven fabric excellent in process passability and excellent in bulkiness. The present invention relates to fine polyester fine fibers which can be finely divided.
従来から、ポリエステル繊維は、衣料用、産業資材用等、種々の用途に使用されているが、中でも細繊度のポリエステル繊維は、その特性を生かし、湿式用不織布の原料や、車両用内装材や吸遮音材の原料として広く用いられている。 BACKGROUND ART Conventionally, polyester fibers have been used for various applications such as clothing and industrial materials. Among them, polyester fibers having a fineness of fineness make use of their characteristics, and are used as a raw material for nonwoven fabrics for wet and interior materials for vehicles and Widely used as a raw material for sound absorbing and sound insulating materials.
例えば、特許文献１は、繊度０．３〜１．０ｄｔｅｘ、繊維長２〜１０ｍｍであり、特定の油剤を付着してなるノークリンプショートカット繊維であって、特定の油剤を付着してなることにより、水中での分散性を良好とし、均一で品位の高い湿式不織布が得られることを開示している。しかし、この繊維は湿式不織布用に適用するノークリンプショートカット繊維であって、湿式不織布を得る際の抄造工程における水中での分散・均一性が向上させるものであり、水中でウェブを作成しない乾式ウェブを作成する技術に、特許文献１の技術を適用しても、同様の効果は奏しない。 For example, Patent Document 1 is a no-crimp short cut fiber having a fineness of 0.3 to 1.0 dtex, a fiber length of 2 to 10 mm, and a specific oil agent attached thereto, and by adhering a specific oil agent, It is disclosed that the dispersibility in water is good and that a uniform and high-quality wet non-woven fabric can be obtained. However, this fiber is a no-crimp shortcut fiber applied for wet non-woven fabrics, which improves dispersion/uniformity in water during the papermaking process when obtaining wet non-woven fabrics, and is a dry web that does not form a web in water. Even if the technique of Patent Document 1 is applied to the technique of creating the, the same effect is not obtained.
また、特許文献２には、単繊維繊度が０．０１〜０．５ｄｔｅｘ、繊維長が３〜６０ｍｍの繊維を吸・遮音材用繊維として用いること、またその繊維として、アクリル繊維は比重が小さく、生産性の観点から好適であることが記載されている。したがって、細い繊度のポリエステル繊維であって、品位の高い繊維を得ることに関しては記載されていない。 Further, in Patent Document 2, a fiber having a single fiber fineness of 0.01 to 0.5 dtex and a fiber length of 3 to 60 mm is used as a fiber for a sound absorbing and sound insulating material, and as the fiber, an acrylic fiber has a small specific gravity. It is described that it is suitable from the viewpoint of productivity. Therefore, there is no description about obtaining a high-quality fiber which is a polyester fiber having a fine fineness.
本発明は、単繊維繊度が０．５ｄｔｅｘ以下の繊度の小さいポリエステル系短繊維において、特に乾式用不織布の原料として用いた場合に、工程通過性が良好で、嵩高性に優れた品位の高い不織布を得ることができる細繊度ポリエステル系短繊維を提供することを課題とする。 INDUSTRIAL APPLICABILITY The present invention is a polyester short fiber having a single fiber fineness of 0.5 dtex or less and a small fineness, and particularly when it is used as a raw material for a non-woven fabric for a dry process, has a good process passage property and a high-quality non-woven fabric having excellent bulkiness An object of the present invention is to provide a polyester fine fiber having a fineness capable of obtaining the above.
本発明者らは、上記の課題を解決するために、すなわち、品位が高い乾式ウェブを得るためには、高品質で均質な細繊度のポリエステル短繊維を得ようと考え、ポリエステル短繊維を構成する樹脂組成物に着目し、鋭意検討した結果、本発明に到達した。 In order to solve the above problems, that is, in order to obtain a dry dry web of high quality, the inventors of the present invention intend to obtain polyester short fibers of high quality and uniform fineness, and configure polyester short fibers. As a result of earnestly studying and focusing on the resin composition to be achieved, the present invention has been achieved.
すなわち、本発明は、単繊維繊度が０．１〜０．５ｄｔｅｘのポリエステル短繊維であり、
短繊維を構成するポリエステル樹脂は、テレフタル酸、エチレングリコール、ジエチレングリコールを構成成分とし、ポリエステル中のジエチレングリコールの含有量が全グリコール成分に対して１．７ｍｏｌ％未満であり、
短繊維の極限粘度が０．５３〜０．６９であり、
短繊維は酸化チタンを含み、短繊維中における酸化チタンの含有量は０．０１〜１．０質量％であること特徴とするポリエステル系細繊度短繊維を要旨とするものである。
That is, the present invention is a polyester short fiber having a single fiber fineness of 0.1 to 0.5 dtex,
The polyester resin constituting the short fibers has terephthalic acid, ethylene glycol, and diethylene glycol as constituent components, and the content of diethylene glycol in the polyester is less than 1.7 mol% with respect to the total glycol component,
The intrinsic viscosity of the short fibers is 0.53 to 0.69,
The short fibers include titanium oxide, and the content of the titanium oxide in the short fibers is 0.01 to 1.0% by mass.
以下、本発明について詳細に説明する。 Hereinafter, the present invention will be described in detail.
本発明の細繊度短繊維を構成するポリエステルは、テレフタル酸、エチレングリコール、ジエチレングリコールを構成成分とする。ポリエステル系短繊維に含まれるジエチレングリコール含有量は全グリコール成分に対して１．７ｍｏｌ％未満である必要がある。１．７ｍｏｌ％を超えると繊維の結晶性が低下することで、耐熱性が低下し、熱収縮率が高くなる。また、不織布作製時の熱処理により捲縮がヘタリ易くなり、得られる不織布の嵩が低下する。ジエチレングリコールの下限は、１．０ｍｏｌ％がよい。 The polyester constituting the fine fine staple fibers of the present invention contains terephthalic acid, ethylene glycol and diethylene glycol as constituent components. The content of diethylene glycol contained in the polyester staple fiber needs to be less than 1.7 mol% with respect to the total glycol component. When it exceeds 1.7 mol %, the crystallinity of the fiber is lowered, the heat resistance is lowered, and the heat shrinkage rate is increased. In addition, the heat treatment during the production of the non-woven fabric makes the crimp more likely to set and reduces the bulk of the resulting non-woven fabric. The lower limit of diethylene glycol is preferably 1.0 mol %.
本発明のポリエステル短繊維は、その極限粘度が０．５３〜０．６９である。さらに極限粘度は０．５５〜０．６８がより好ましい。繊維の極限粘度がこの範囲であることにより、均質で品位の高い短繊維となる。短繊維の極限粘度の範囲が０．５３〜０．６９とするためには、短繊維を製造する際に用いる原料であるところのポリエステル樹脂チップの極限粘度は、０．５５〜０．７１の範囲とする。ポリエステル樹脂チップの極限粘度が０．５５を下回ると、紡糸工程における紡糸口金での計量性が低下し、紡糸における繊径のバラつきが大きくなり、紡糸性が悪化し、得られる短繊維の品位が低下する。一方、ポリエステル樹脂チップの極限粘度が０．７１を超えると、紡糸後の未延伸糸伸度が低くなり、０．５デシテックス以下の細繊度短繊維を得るための延伸倍率（２．８倍以上）が掛けられなくなり、所望する繊度が得られずに太繊度の繊維となる。 The polyester short fibers of the present invention have an intrinsic viscosity of 0.53 to 0.69. Furthermore, the intrinsic viscosity is more preferably 0.55 to 0.68. When the intrinsic viscosity of the fiber is within this range, it becomes a homogeneous and high-quality short fiber. In order for the range of the intrinsic viscosity of the short fibers to be 0.53 to 0.69, the intrinsic viscosity of the polyester resin chip, which is a raw material used when producing the short fibers, is 0.55 to 0.71. Range. When the intrinsic viscosity of the polyester resin chip is less than 0.55, the metering property in the spinneret in the spinning process is reduced, the variation in the fiber diameter in the spinning is increased, the spinnability is deteriorated, and the quality of the obtained short fiber is deteriorated. descend. On the other hand, when the intrinsic viscosity of the polyester resin chip exceeds 0.71, the undrawn yarn elongation after spinning becomes low, and a draw ratio (2.8 times or more for obtaining a fine fine staple fiber of 0.5 decitex or less). ) Is not applied, and a desired fineness is not obtained, and a fiber having a large fineness is obtained.
本発明の短繊維は、酸化チタンを含んでおり、短繊維中の酸化チタンの含有量は０．０１〜１．０質量％である。酸化チタンは、上記したポリエステル樹脂中に含まれるものであり、短繊維を構成するポリエステル樹脂中に酸化チタンが含まれることで、製造工程や加工工程で接触する金属等との摩擦が低下し、紡糸口金表面からの溶融樹脂の面離れが良くなり、紡糸性が良好となる。また摩擦が低下することにより延伸時の単糸切れを抑制することができ、均質な細繊度短繊維を得ることができる。酸化チタンの含有量は０．０１〜１．０質量％の範囲が好ましく、中でも０．０２〜０．４質量％であることが好ましい。酸化チタンの含有量が０．０１質量％未満であると摩擦低下の効果が発揮しにくい。一方、１．０質量％を超えると紡糸性および延伸性が悪化する。 The short fiber of the present invention contains titanium oxide, and the content of titanium oxide in the short fiber is 0.01 to 1.0% by mass. Titanium oxide is contained in the polyester resin described above, by containing titanium oxide in the polyester resin constituting the short fibers, the friction with the metal or the like to be contacted in the manufacturing process or processing step is reduced, The surface separation of the molten resin from the surface of the spinneret becomes good, and the spinnability becomes good. Further, since the friction is reduced, it is possible to suppress the breakage of single yarn during drawing, and it is possible to obtain a uniform short fine fiber. The content of titanium oxide is preferably in the range of 0.01 to 1.0% by mass, and more preferably 0.02 to 0.4% by mass. When the content of titanium oxide is less than 0.01% by mass, it is difficult to exert the effect of reducing friction. On the other hand, if it exceeds 1.0% by mass, the spinnability and stretchability will deteriorate.
酸化チタンは、平均粒径が０．１〜１μｍの範囲にあるものを用いるとよく、０．２〜０．８μｍであることがより好ましい。なお、本発明における平均粒径は、酸化チタンをエチレングリコール溶液に微分散させた後、島津製作所社製のレーザー回折式粒度分布測定装置ＳＡＬＤ−７１００を用い、体積分布基準換算、屈折率２．００−０．００ｉの条件で測定するものである。平均粒径が０．１μｍ未満の酸化チタンを使用すると、ポリエステル樹脂の重合時や紡糸時に凝集が発生し易くなる。一方、１μｍを超える平均粒径の酸化チタンを用いると紡糸時に切糸が発生し易くなる。 As titanium oxide, those having an average particle size in the range of 0.1 to 1 μm are preferably used, and more preferably 0.2 to 0.8 μm. In addition, the average particle diameter in the present invention is obtained by finely dispersing titanium oxide in an ethylene glycol solution, and then using a laser diffraction particle size distribution analyzer SALD-7100 manufactured by Shimadzu Corporation, in terms of volume distribution standard and a refractive index of 2. It is measured under the condition of 00-0.00i. When titanium oxide having an average particle size of less than 0.1 μm is used, aggregation easily occurs during polymerization of the polyester resin or during spinning. On the other hand, if titanium oxide having an average particle size of more than 1 μm is used, a cutting yarn is likely to occur during spinning.
繊維中に含まれる酸化チタンの粒度分布については、粒子径０．６１８μｍ未満の粒子の頻度が６０〜９５％、粒子径０．６１８μｍ以上の粒子の頻度が５〜４０％、２．６μｍを超える粒子の頻度が０％であることが好ましい。この範囲とすることで、紡糸での切糸を抑制することができ、より均質な細繊度短繊維を得ることができる。また、この範囲の粒度分布とし、０．６１８μｍを超える粒子を一定割合含有することで、低い酸化チタン濃度でも効果的に繊維の摩擦を低下することができ、延伸での単糸切れを抑制することができる。なお、粒度分布をこの範囲とするために、所定の粒度分布の酸化チタンを１種類用いてもよいし、平平均粒径の異なる複数の酸化チタンを用いてもよい。 Regarding the particle size distribution of titanium oxide contained in the fiber, the frequency of particles having a particle size of less than 0.618 μm is 60 to 95%, the frequency of particles having a particle size of 0.618 μm or more is 5 to 40%, and exceeds 2.6 μm. The particle frequency is preferably 0%. By setting it in this range, it is possible to suppress the cutting yarn in spinning, and it is possible to obtain a more uniform fine fineness staple fiber. Further, by having a particle size distribution in this range and containing a certain proportion of particles exceeding 0.618 μm, it is possible to effectively reduce the friction of the fiber even with a low titanium oxide concentration, and to prevent single yarn breakage during drawing. be able to. In order to set the particle size distribution within this range, one type of titanium oxide having a predetermined particle size distribution may be used, or a plurality of titanium oxides having different average particle sizes may be used.
さらに、ポリエステル樹脂中に、その効果を損なわない範囲で、酸化防止剤、紫外線吸収剤、光安定剤、顔料、抗菌剤、導電性付与剤、親水剤、吸水剤等を含有させてもよい。 Further, the polyester resin may contain an antioxidant, an ultraviolet absorber, a light stabilizer, a pigment, an antibacterial agent, a conductivity-imparting agent, a hydrophilic agent, a water-absorbing agent, etc. within a range that does not impair the effect.
ポリエステル系短繊維の断面形状は特に限定されるものではないが、円形断面であることが好ましい。円形断面とすることで、紡糸性良く、細繊度の短繊維を得ることができる。 The cross-sectional shape of the polyester-based short fiber is not particularly limited, but a circular cross-section is preferable. With a circular cross section, short fibers with good spinnability and fineness can be obtained.
本発明のポリエステル系短繊維の繊度は０．１〜０．５ｄｔｅｘである。繊度が０．１ｄｔｅｘ未満になると、紡糸延伸性が低下し、品位に劣る繊維となる。また、より細繊度とするため紡糸時の吐出量を低くする必要があり、紡糸性が悪化する。また生産レートが低くなり、高コストとなる。よって、繊度は、０．３〜０．５ｄｔｅｘが好ましく、より好ましくは０．４〜０．５ｄｔｅｘである。一方、０．５ｄｔｅｘを超えると吸音・遮音材用の繊維として用いた場合に、性能が低下する。 The fineness of the polyester short fibers of the present invention is 0.1 to 0.5 dtex. When the fineness is less than 0.1 dtex, the spinnability and drawability deteriorate, resulting in poor quality fiber. Further, in order to obtain a finer fiber, it is necessary to reduce the discharge amount during spinning, which deteriorates the spinnability. In addition, the production rate becomes low and the cost becomes high. Therefore, the fineness is preferably 0.3 to 0.5 dtex, more preferably 0.4 to 0.5 dtex. On the other hand, if it exceeds 0.5 dtex, the performance deteriorates when used as a fiber for a sound absorbing/sound-insulating material.
本発明におけるポリエステル系細繊度短繊維は、繊維径の変動率が１０％未満である。繊維径の変動率とは、繊維径のバラつきの程度を指す。繊維径の変動率は、８％以下であることが好ましく、５．０％以下であることがより好ましい。１０％を超えると、紡糸時の切糸が増加し操業性が悪化する。また得られる短繊維の品質が低下する。繊維径の変動率は、繊維横断面を光学顕微鏡等で観察したとき、５０本の繊維について繊維の直径を測定し、標準偏差と平均値を算出した後、下式により算出する。
繊維径の変動率（％）＝（繊維直径の標準偏差／繊維直径の平均値）×１００
The polyester-based fine-fineness short fibers in the present invention have a variation rate of the fiber diameter of less than 10%. The fluctuation rate of the fiber diameter refers to the degree of variation in the fiber diameter. The variation rate of the fiber diameter is preferably 8% or less, and more preferably 5.0% or less. If it exceeds 10%, the number of cutting yarns at the time of spinning increases and the operability deteriorates. In addition, the quality of the obtained short fibers is deteriorated. The variation rate of the fiber diameter is calculated by the following formula after measuring the fiber diameter of 50 fibers when observing the cross section of the fiber with an optical microscope or the like, calculating the standard deviation and the average value.
Variation rate of fiber diameter (%)=(standard deviation of fiber diameter/average value of fiber diameter)×100
繊維径の変動率を１０％未満とするために、面径が１８０ｍｍ程度の紡糸口金の場合、孔数を１５００〜２５００個とすることが好ましく、１８００〜２２００個とすることが、より好ましい。孔数を前述の範囲とすることで、紡糸レートを低くせずに、繊維径のバラつきの小さい、低コストで高品質な短繊維を得ることができる。 In order to set the variation rate of the fiber diameter to less than 10%, in the case of a spinneret having a surface diameter of about 180 mm, the number of holes is preferably 1500 to 2500, and more preferably 1800 to 2200. By setting the number of holes within the above range, it is possible to obtain high-quality short fibers at a low cost with a small variation in fiber diameter without lowering the spinning rate.
なお、紡糸口金の孔径は直径φ０．１４〜０．１６ｍｍの範囲とすることが好ましい。直径φ０．１４ｍｍ未満であると、紡糸後のノズル再生の難易度が高くなり、ノズル孔の孔詰まりが発生しやすくなる。また直径０．１６ｍｍを超えると、紡糸時のドラフトが高くなり紡糸性が悪化する。また、繊維径のバラつきが大きくなる。 The hole diameter of the spinneret is preferably in the range of diameter φ0.14 to 0.16 mm. If the diameter is less than 0.14 mm, the difficulty of nozzle regeneration after spinning becomes high, and clogging of nozzle holes is likely to occur. If the diameter exceeds 0.16 mm, the draft during spinning becomes high and the spinnability deteriorates. In addition, the variation in fiber diameter becomes large.
本発明のポリエステル系細繊度短繊維を１７０℃、１分間の条件で乾熱処理した際の熱収縮率は１％未満である。１％を超えると、不織布作製時の熱処理により、嵩が低下する。 The heat shrinkage ratio of the polyester fine fine staple fibers of the present invention when dry heat treated at 170° C. for 1 minute is less than 1%. If it exceeds 1%, the bulk decreases due to the heat treatment during the production of the nonwoven fabric.
本発明のポリエステル系細繊度短繊維は、繊維の製造工程において捲縮が付与されていることが好ましい。繊維長２５ｍｍ当たりの捲縮数は１０〜１８ケであることが好ましく、捲縮率は９〜１７％の範囲であることが好ましく、１０〜１６％の範囲であることがより好ましい。捲縮数が１０ケ／２５ｍｍ未満であると繊維同士の絡みが弱くなり、不織布作製工程での短繊維の搬送性が悪化する。一方、１８ケ／２５ｍｍを超えると、繊維の開繊性が悪くなり、得られる不織布の地合いが悪くなる。また、捲縮率は９％未満であると繊維同士の絡みが弱くなり、搬送性が悪化する。また、ウェブの強度が低下する。さらに嵩高性に優れた不織布を得ることが困難になる。捲縮率が１７％を超えると、繊維の開繊性が悪くなり、得られる不織布の地合いが悪くなる。 It is preferable that the polyester type fine fine short fibers of the present invention are crimped in the fiber manufacturing process. The number of crimps per 25 mm of fiber length is preferably 10 to 18, and the crimp rate is preferably 9 to 17%, more preferably 10 to 16%. If the number of crimps is less than 10/25 mm, the entanglement between fibers becomes weak, and the transportability of short fibers in the non-woven fabric manufacturing process deteriorates. On the other hand, when the number exceeds 18/25 mm, the fiber openability is deteriorated and the texture of the resulting nonwoven fabric is deteriorated. If the crimping rate is less than 9%, the entanglement between the fibers becomes weak and the transportability deteriorates. Also, the strength of the web is reduced. Further, it becomes difficult to obtain a non-woven fabric excellent in bulkiness. When the crimping rate exceeds 17%, the fiber openability is deteriorated and the texture of the resulting nonwoven fabric is deteriorated.
捲縮は、押し込み式クリンパーを用いて付与することが好ましい。押し込み式クリンパーに繊維を導入する前には繊維を収束させる必要があり、従来は、水を付与することで収束させるが、本発明においては、水ではなく、油剤をスプレー方式で付与することが好ましい。また、押し込み式クリンパーに繊維を導入する直前に、１５０〜１８０℃の加熱ローラーおよびスチームにより繊維を加熱することが好ましい。本発明のポリエステル系細繊度短繊維は０．１〜０．５ｄｔｅｘの細繊度であるため、一般的な繊度の繊維と比較して捲縮の付与および固定化が難しく、捲縮率は低くなる傾向がある。前述した方法を採用することにより、低水分率の状態で繊維の収束性を保ちつつ、高温下での捲縮付与が可能となり、細繊度繊維の場合でも高捲縮率の短繊維を得ることができる。また、高温下で捲縮が付与されているため、不織布作製時の熱処理による捲縮のヘタリを抑制することができる。 The crimp is preferably applied using a push-in type crimper. It is necessary to converge the fibers before introducing the fibers into the push-in type crimper, and conventionally, the fibers are converged by applying water, but in the present invention, not the water but the oil agent may be applied by a spray method. preferable. Further, immediately before introducing the fiber into the push-in type crimper, it is preferable to heat the fiber with a heating roller and steam at 150 to 180°C. Since the polyester fine-fine short fibers of the present invention have a fineness of 0.1 to 0.5 dtex, it is more difficult to apply and fix crimps and the crimp ratio is lower than that of fibers having general fineness. Tend. By adopting the method described above, crimping can be applied at a high temperature while maintaining the fiber convergence in a low moisture content state, and even in the case of fine-fineness fibers, short fibers with a high crimping rate can be obtained. You can Further, since crimping is applied at a high temperature, it is possible to suppress the settling of the crimp due to the heat treatment during the production of the nonwoven fabric.
捲縮付与後の繊維は、乾燥機にて熱処理されることなく、冷却コンベアで冷却され、その後、カッターにて所定の長さにカットされることが好ましい。捲縮付与後に乾燥機にて熱処理を行わずに冷却することで、クリンパーにて付与した捲縮がヘタることなく、良好に捲縮が付与された短繊維を得ることができる。 It is preferable that the crimped fiber is cooled by a cooling conveyor without being heat-treated by a dryer, and then cut into a predetermined length by a cutter. By cooling without applying heat treatment in a drier after applying the crimps, the crimps applied with the crimper can be obtained without sagging and crimped staple fibers can be obtained.
本発明の短繊維は、標準状態（２５℃）で測定した捲縮数（ＸＡ）と、１７０℃、１分間の熱処理後の捲縮数（ＸＢ）は、下記条件を満たすことが好ましい。下記の条件を満たすことで、不織布作製時の熱処理による捲縮のヘタリを抑制することができ、嵩高性に優れ、均質な高品質の不織布を得ることができる。
（１）ＸＢ／ＸＡ≧０．７
In the short fiber of the present invention, the number of crimps (X A ) measured in a standard state (25° C.) and the number of crimps (X B ) after heat treatment at 170° C. for 1 minute preferably satisfy the following conditions. .. By satisfying the following conditions, it is possible to suppress the settling of the crimps due to the heat treatment during the production of the nonwoven fabric, and it is possible to obtain a nonwoven fabric with excellent bulkiness and uniform quality.
(1) X B /X A ≧0.7
本発明の短繊維の繊維長は２０〜４４ｍｍであることが好ましく、中でも２５〜３２ｍｍであることが好ましい。繊維長が２０ｍｍ未満であると、繊維同士の絡みが弱くなり不織布作製工程での短繊維の搬送性が悪化する。一方、４４ｍｍを超えると繊維の開繊性が悪くなり、得られる不織布の地合いが悪くなる。 The short fiber of the present invention preferably has a fiber length of 20 to 44 mm, and more preferably 25 to 32 mm. If the fiber length is less than 20 mm, the entanglement between the fibers becomes weak and the transportability of the short fibers in the non-woven fabric manufacturing process deteriorates. On the other hand, when it exceeds 44 mm, the openability of the fiber is deteriorated and the texture of the obtained nonwoven fabric is deteriorated.
本発明の短繊維を用いて不織布とする際には、本発明の短繊維以外に、熱融着繊維等のバインダーとなる繊維と混合して不織布や繊維成型体とするのがよい。また、本発明の効果を損なわない範囲において、他の材料を混合したり併用したりしてもよい。 When the short fiber of the present invention is used to form a nonwoven fabric, it is preferable to mix the short fiber of the present invention with a fiber serving as a binder such as a heat fusion fiber to form a nonwoven fabric or a fiber molded body. Further, other materials may be mixed or used in combination as long as the effects of the present invention are not impaired.
本発明の細繊度短繊維は、均質で品位が高いため、得られる不織布においても、均一な性能を発揮するため、均質で高品位の不織布や繊維成型体が得られる。このような不織布や繊維成型体は、均質であるため、吸音・遮音材として好適に適用することが期待できる。 Since the fine fine staple fibers of the present invention are homogeneous and of high quality, even the obtained nonwoven fabric exhibits uniform performance, so that a homogeneous and high-quality nonwoven fabric or fiber molded body can be obtained. Since such a non-woven fabric or a fiber molding is homogeneous, it can be expected to be suitably applied as a sound absorbing/sound insulating material.
本発明によれば、均質なポリエステル系細繊度短繊維を得ることができることから、本発明の短繊維を、特に乾式用不織布の原料として用いた場合に、工程通過性が良好で、嵩高性に優れた高品質な不織布を得ることができる。 According to the present invention, since it is possible to obtain a homogeneous polyester fine fiber short fibers, when using the short fibers of the present invention, particularly when used as a raw material for a dry process nonwoven fabric, good process passability and bulkiness are achieved. An excellent high quality nonwoven fabric can be obtained.
次に、本発明を実施例により具体的に説明する。なお、実施例における特性値等の測定法は次のとおりである。
（１）極限粘度〔η〕
フェノールとテトラクロロエタンとの等重量混合物を溶媒とし、２０℃で、繊維０．２ｇを試料として投入し、濃度を０．５％として、相対粘度〔ηｃｒ〕を測定し、その値を用いて、下式により極限粘度〔η〕を算出した。
Next, the present invention will be specifically described with reference to examples. In addition, the measuring method of the characteristic value etc. in an Example is as follows.
(1) Intrinsic viscosity [η]
Using an equal weight mixture of phenol and tetrachloroethane as a solvent, 0.2 g of fiber was added as a sample at 20° C., the concentration was 0.5%, the relative viscosity [η cr ] was measured, and the value was used. The intrinsic viscosity [η] was calculated by the following formula.
（２）ジエチレングリコール（ＤＥＧ）含有量
繊維２．２ｇを三角フラスコに投入し、０．８等量の水酸化カリウムメタノール溶液を加え、マグネチックスターラ攪拌下加熱還流してケン化を行う。その後、テレフタル酸を加え中和し、沈殿物を濾過し、ガスクロマトグラフィにて濾液中のＤＥＧ含有量を測定した。
（３）酸化チタン含有量
試料として繊維１０ｇを溶融固化させて円盤状の成型体を作製し、リガク社製蛍光Ｘ線分析装置ＺＳＭ Ｐｒｉｍｕｓを用いて酸化チタン含有量を測定した。
（４）酸化チタンの粒度分布
試料として繊維１０ｍｇを、フェノールとテトラクロロエタンとの等質量混合物に溶解し、島津製作所社製のレーザー回折式粒度分布測定装置ＳＡＬＤ−７１００にて、繊維中に含まれる酸化チタンの粒度分布を、体積分布基準換算、屈折率２．００−０．００ｉの条件で測定した。
（５）繊維繊度
ＪＩＳ Ｌ１０１５ ８．５．１ Ｂ法により測定した。
（６）繊維径の変動率（％）
繊維横断面を光学顕微鏡で観察し、５０本の繊維について繊維の直径を測定し、繊維径の標準偏差および繊維径の平均値を求めた後、下式により変動率を算出した。
繊維径の変動率（％）＝（繊維径の標準偏差／繊維径の平均値）×１００
（７）繊維長
ＪＩＳ Ｌ１０１５ ８．４．１ Ａ法により測定した。
（８）乾熱収縮率
ＪＩＳ Ｌ１０１５ ８．１５に基づき測定した。なお測定温度は１７０℃、処理時間は１分とした。
（９）捲縮数
ＪＩＳ Ｌ１０１５ ８．１２．１および８．１２．２により測定した。このとき、標準状態（２５℃）で測定した捲縮数（ＸＡ）と、１７０℃、１分間の熱処理後の捲縮数（ＸＢ）を測定し、下記条件を満たすものを合格（〇）とした。
（１）ＸＢ／ＸＡ≧０．７
（１０）紡糸性
繊維紡糸工程における切糸回数について、紡糸量１トンあたり３回未満を合格（○）とし、３回以上を不合格（×）とした。
（１１）延伸性
繊維延伸工程における単糸切れ回数が、延伸量１トンあたり３回未満を合格（○）とし、３回以上を不合格（×）とした。
（１２）工程通過性
有限会社竹内製作所製ＣＨ−５００ホッパーフィーダーのボックスに繊維１０ｋｇを順次投入し、スパイクラチスで持ち揚げ方式（設置面から約２．３ｍの高さまで上げる）により、繊維を搬送し、搬送された繊維量（質量）を測定した。「搬送された繊維量」を「投入した繊維量（１０ｋｇ）」で除した値に１００を乗じた値を搬送率とし、搬送率が、９５％以上のものを合格（〇）、９５％未満を不合格（×）とした。
（１３）嵩高性
得られた繊維とユニチカ製１１０℃融点の芯鞘型熱融着繊維（芯がポリエチレンテレフタレート、鞘が融点１１０℃の共重合ポリエステルにより構成された短繊維であって、２．２ｄｔｅｘ×５１ｍｍ）を混率８０／２０質量％の条件にてカードウェブ（目付１００ｇ／ｍ２）を作製し、温度１５０℃、風量３８ｍ３／分、処理時間１分間の条件で熱風乾燥機にて熱処理を行い、目付１００ｇ／ｍ２の不織布を作製した。熱処理前のカードウェブと熱処理後の不織布の厚み（無加重）をそれぞれ測定し、それぞれのみかけ密度を算出した。熱処理前後のみかけ密度の変化において、熱処理後の嵩低下率が２０％未満の場合を合格（○）、２０％を超えるものを不合格（×）とした。
(2) Content of Diethylene Glycol (DEG) 2.2 g of fiber is put into an Erlenmeyer flask, 0.8 equivalent of a potassium hydroxide methanol solution is added, and the mixture is heated under reflux with magnetic stirring to perform saponification. Then, terephthalic acid was added for neutralization, the precipitate was filtered, and the DEG content in the filtrate was measured by gas chromatography.
(3) Titanium oxide content As a sample, 10 g of fiber was melted and solidified to prepare a disk-shaped molded body, and the titanium oxide content was measured using a fluorescent X-ray analyzer ZSM Primus manufactured by Rigaku Corporation.
(4) As a particle size distribution sample of titanium oxide, 10 mg of fiber was dissolved in an equal mass mixture of phenol and tetrachloroethane, and contained in the fiber with a laser diffraction particle size distribution analyzer SALD-7100 manufactured by Shimadzu Corporation. The particle size distribution of titanium oxide was measured under the conditions of a volume distribution standard conversion and a refractive index of 2.00 to 0.00i.
(5) Fiber fineness Measured according to JIS L1015 8.5.1 B method.
(6) Variation rate of fiber diameter (%)
The cross-section of the fiber was observed with an optical microscope, the fiber diameter was measured for 50 fibers, the standard deviation of the fiber diameter and the average value of the fiber diameter were determined, and then the variation rate was calculated by the following formula.
Variation rate of fiber diameter (%)=(standard deviation of fiber diameter/average value of fiber diameter)×100
(7) Fiber length Measured by JIS L1015 8.4.1 A method.
(8) Dry heat shrinkage It was measured based on JIS L1015 8.15. The measurement temperature was 170° C. and the treatment time was 1 minute.
(9) Number of crimps Measured according to JIS L1015 8.12.1 and 8.12.2. At this time, the number of crimps (X A ) measured in the standard state (25° C.) and the number of crimps (X B ) after heat treatment at 170° C. for 1 minute were measured, and those satisfying the following conditions were accepted (◯). ).
(1) X B /X A ≧0.7
(10) Spinnability Regarding the number of cutting threads in the fiber spinning step, less than 3 times per 1 ton of the spinning amount was passed (◯), and 3 times or more was rejected (x).
(11) Stretchability Regarding the number of single yarn breakages in the fiber stretching step, less than 3 times per 1 ton of the stretched amount was passed (◯), and 3 times or more was rejected (x).
(12) Process passability 10 kg of fibers are sequentially charged into the CH-500 hopper feeder box manufactured by Takeuchi Seisakusho Co., Ltd., and the fibers are transported by the spike lattice (raising to a height of about 2.3 m from the installation surface). Then, the amount (mass) of the transported fiber was measured. The value obtained by dividing the "conveyed fiber amount" by the "input fiber amount (10 kg)" and multiplying by 100 is taken as the conveying rate, and the conveying rate of 95% or more is passed (○), less than 95%. Was designated as a failure (x).
(13) Bulkiness The obtained fiber and a core-sheath type heat-sealing fiber made of Unitika and having a melting point of 110° C. (a short fiber having a core made of polyethylene terephthalate and a sheath made of a copolymerized polyester having a melting point of 110° C., 2. 2 dtex×51 mm) to prepare a card web (area weight: 100 g/m 2 ) with a mixing ratio of 80/ 20 % by mass, and use a hot air dryer under the conditions of a temperature of 150° C., an air volume of 38 m 3 /min, and a treatment time of 1 minute. Heat treatment was performed to produce a nonwoven fabric having a basis weight of 100 g/m 2 . The thicknesses of the card web before heat treatment and the nonwoven fabric after heat treatment (without weight) were measured, and the apparent densities thereof were calculated. In the change of the apparent density before and after the heat treatment, the case where the bulk reduction rate after the heat treatment was less than 20% was judged as pass (∘), and the one in which the bulk reduction rate exceeded 20% was judged as fail (x).
実施例１
極限粘度０．７０、酸化チタン量０．３７質量％（平均粒径０．３μｍ、平均粒径０．６μｍの酸化チタンを重合時に９／１の比率で添加）のポリエステル（全酸成分に対してテレフタル酸１００ｍｏｌ％、全グリコール成分に対してエチレングリコール９８．５ｍｏｌ％、ジエチレングリコール１．５ｍｏｌ％）を孔数２１６０Ｈ、孔径０．１６ｍｍの紡糸口金を用い、吐出量３１２ｇ／分、紡糸温度２９７℃、紡糸速度１１７６ｍ／分で溶融紡糸を行った。切糸回数は１．５回／トンであった。得られた未延伸糸を収束し、５０ｋｔｅｘのトウとし、延伸温度７０℃、延伸倍率３．２倍の条件で延伸した。延伸後、温度１９９℃のヒートドラムにて熱セットを行い、その後、ラウリルフォスフェートカリウム塩を主成分とする油剤をスプレー方式でトウに付与し、１７０℃の加熱ローラーでトウを加熱し、その後、スチームによる加熱を行い、押し込み式クリンパーに導入し捲縮を付与した。その後、トウを乾燥機で熱処理を行わずに、冷却コンベアにてトウを冷却し、３２ｍｍにカットし、細繊度短繊維を得た。得られた短繊維を用いて、前記した測定方法の（１３）嵩高性の記載に基づき、不織布を作製した。
Example 1
Intrinsic viscosity 0.70, titanium oxide amount 0.37% by mass (titanium oxide having an average particle size of 0.3 μm and an average particle size of 0.6 μm was added at a ratio of 9/1 during polymerization) polyester (based on all acid components) Terephthalic acid 100 mol%, ethylene glycol 98.5 mol%, diethylene glycol 1.5 mol% based on all glycol components) using a spinneret with a hole number of 2160H and a hole diameter of 0.16 mm, discharge rate of 312 g/min, spinning temperature of 297° C. Melt spinning was performed at a spinning speed of 1176 m/min. The number of cutting threads was 1.5 times/ton. The obtained unstretched yarn was converged, made into 50 ktex tow, and stretched under the conditions of a stretching temperature of 70° C. and a stretching ratio of 3.2 times. After stretching, heat setting was performed with a heat drum at a temperature of 199° C., then an oil agent containing lauryl phosphate potassium salt as a main component was applied to the tow by a spray method, and the tow was heated with a heating roller at 170° C. Then, it was heated with steam and introduced into a push-in type crimper to provide crimping. After that, the tow was cooled by a cooling conveyer without being heat-treated by a dryer and cut into 32 mm to obtain fine fibers with short fineness. Using the obtained short fibers, a non-woven fabric was produced based on the description of (13) Bulkiness in the above-mentioned measurement method.
得られた短繊維と不織布の特性は表１に示す通りであった。なお、得られた繊維中の酸化チタンの粒度分布は、粒子径０．６１８μｍ未満の粒子が６９％、粒子径０．６１８を超える粒子が３１％、２．６μｍを超える粒子が０％であった。 The properties of the obtained short fibers and nonwoven fabric are shown in Table 1. The particle size distribution of titanium oxide in the obtained fiber was 69% for particles having a particle size of less than 0.618 μm, 31% for particles having a particle size of more than 0.618, and 0% for particles having a particle size of more than 2.6 μm. It was
実施例２
極限粘度０．６２、酸化チタン量０．０２質量％（平均粒径０．３μｍ、平均粒径０．６μｍの酸化チタンを重合時に９／１の比率で添加）のポリエステル（全酸成分に対してテレフタル酸１００ｍｏｌ％、全グリコール成分に対してエチレングリコール９８．５ｍｏｌ％、ジエチレングリコール１．５ｍｏｌ％）を孔数２１６０Ｈ、孔径０．１６ｍｍの紡糸口金を用い、吐出量３３４ｇ／分、紡糸温度２９７℃、紡糸速度１１７６ｍ／分で溶融紡糸を行った。切糸回数は２．３回／トンであった。延伸倍率を３．４倍とした以外は、実施例１と同様にして短繊維を得た。得られた短繊維と不織布の特性は表１に示す通りであった。なお、得られた繊維中の酸化チタンの粒度分布は、粒子径０．６１８μｍ未満の粒子が６９％、粒子径０．６１８を超える粒子が１２％、２．６μｍを超える粒子が０％であった。
Example 2
Intrinsic viscosity 0.62, titanium oxide amount 0.02% by mass (titanium oxide having an average particle size of 0.3 μm and an average particle size of 0.6 μm was added at a ratio of 9/1 during polymerization) polyester (based on all acid components) Terephthalic acid 100mol%, ethylene glycol 98.5mol%, diethylene glycol 1.5mol% based on all glycol components) using a spinneret with a hole number of 2160H and a hole diameter of 0.16mm, discharge rate 334g/min, spinning temperature 297°C. Melt spinning was performed at a spinning speed of 1176 m/min. The number of cutting threads was 2.3 times/ton. Short fibers were obtained in the same manner as in Example 1 except that the draw ratio was 3.4 times. The properties of the obtained short fibers and nonwoven fabric are shown in Table 1. The particle size distribution of titanium oxide in the obtained fiber was 69% for particles having a particle size of less than 0.618 μm, 12% for particles having a particle size of more than 0.618, and 0% for particles having a particle size of more than 2.6 μm. It was
比較例１〜２
極限粘度が０．７４のポリエステルを用いたこと（比較例１）極限粘度が０．５１のポリエステルを用いたこと（比較例２）以外は、実施例１と同様に行った。
Comparative Examples 1-2
Example 1 was repeated except that a polyester having an intrinsic viscosity of 0.74 was used (Comparative Example 1) and a polyester having an intrinsic viscosity of 0.51 was used (Comparative Example 2).
比較例３
テレフタル酸１００ｍｏｌ％、エチレングリコール９７．５ｍｏｌ％、ジエチレングリコール２．５ｍｏｌ％、のポリエステルを用いた以外は、実施例１と同様に行った。
Comparative Example 3
The same procedure as in Example 1 was carried out except that a polyester containing 100 mol% of terephthalic acid, 97.5 mol% of ethylene glycol and 2.5 mol% of diethylene glycol was used.
比較例４
酸化チタン含有量が０質量％のポリエステルを用いた以外は、実施例１と同様に行った。
Comparative Example 4
The same procedure as in Example 1 was carried out except that a polyester having a titanium oxide content of 0 mass% was used.
比較例５
酸化チタン含有量が２．０質量％のポリエステルを用いた以外は、実施例１と同様に行った。
Comparative Example 5
The same procedure as in Example 1 was performed except that polyester having a titanium oxide content of 2.0% by mass was used.
表１から明らかなように、実施例１〜２では紡糸性および延伸性良く細繊度短繊維を得
ることができ、得られた短繊維の捲縮特性、熱収縮率、工程通過性は優れるものであり、
不織布の嵩高性に優れるものであった。
As is clear from Table 1, in Examples 1 and 2, fine fiber short fibers can be obtained with good spinnability and drawability, and the obtained short fibers have excellent crimp characteristics, heat shrinkage, and process passability. And
The non-woven fabric was excellent in bulkiness.
一方、比較例１は、繊維の極限粘度が高く、紡糸後の未延伸糸伸度が低くなったため、
０．５ｄｔｅｘ未満の細繊度短繊維を得るための延伸倍率を掛けられず、延伸倍率２．５
５倍で延伸したことから、太繊度となった。なお、本発明が目的とする繊度でないことか
ら、繊維としての評価は行わなかった。
On the other hand, in Comparative Example 1, since the intrinsic viscosity of the fiber was high and the undrawn yarn elongation after spinning was low,
A draw ratio of 2.5 cannot be applied in order to obtain short fibers having a fineness of less than 0.5 dtex.
Since it was stretched 5 times, the fineness was increased. The fiber was not evaluated because the fineness was not the object of the present invention.
比較例２は、ポリエチレンテレフタレートの極限粘度が低いため、紡糸工程における紡
糸口金での計量性が低下したことで、繊維径のバラつきが大きくなり、切糸が多発し、細
繊度の短繊維を得ることができなかった。
In Comparative Example 2, since the intrinsic viscosity of polyethylene terephthalate is low, the metering property of the spinneret in the spinning process is reduced, the variation of the fiber diameter is increased, the number of cutting yarns is increased, and a short fiber having a fineness is obtained. I couldn't.
比較例３は、繊維のジエチレングリコール含有量が多いため、熱収縮率が高くなり、ま
た熱処理後の捲縮特性が低下した。
In Comparative Example 3, since the fiber contained a large amount of diethylene glycol, the heat shrinkage ratio was high, and the crimp property after heat treatment was deteriorated.
比較例４は、酸化チタンの含有量が０質量％であり、紡糸口金表面からの溶融ポリマー
の面離れが悪くなり、切糸が多発し、細繊度の短繊維を得ることができなかった。
In Comparative Example 4, the content of titanium oxide was 0% by mass, the surface separation of the molten polymer from the surface of the spinneret was deteriorated, the number of cutting threads was increased, and short fibers having a fineness could not be obtained.
比較例５は、酸化チタンの含有量が多すぎたため、紡糸性および延伸性が悪化した。
In Comparative Example 5, since the content of titanium oxide was too large, the spinnability and drawability were deteriorated.
Claims (9)
短繊維を構成するポリエステルは、テレフタル酸、エチレングリコール、ジエチレングリコールを構成成分とし、ポリエステル中のジエチレングリコールの含有量が全グリコール成分に対して１．７ｍｏｌ％未満であり、
短繊維の極限粘度が０．５３〜０．６９であり、
短繊維は酸化チタンを含み、短繊維中における酸化チタンの含有量は０．０１〜１．０質量％であること特徴とするポリエステル系細繊度短繊維。 Polyester staple fibers having a single fiber fineness of 0.1 to 0.5 dtex,
The polyester constituting the short fibers has terephthalic acid, ethylene glycol, and diethylene glycol as constituent components, and the content of diethylene glycol in the polyester is less than 1.7 mol% with respect to the total glycol component,
The intrinsic viscosity of the short fibers is 0.53 to 0.69,
The short fibers include titanium oxide, and the content of titanium oxide in the short fibers is 0.01 to 1.0 mass%.
（１）ＸＢ／ＸＡ≧０．７ 4. The number of crimps (X A ) measured in a standard state and the number of crimps (X B ) after heat treatment at 170° C. for 1 minute satisfy the following condition (1): 4. Or a polyester-based fine fineness staple fiber according to item 1.
(1) X B /X A ≧0.7
A sound absorbing/insulating material, wherein the dry nonwoven fabric according to claim 8 is used as a sound absorbing material or a sound insulating material.
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| CN114182385B (en) * | 2021-12-20 | 2023-08-29 | 扬州富威尔复合材料有限公司 | Preparation method of fine denier polyester staple fiber |
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