JP2020117432A - Bundled fiber for adding hydraulic hardened body, premix cement composition and hydraulic hardened body containing the same, and method for producing the same - Google Patents

Abstract

To provide: a bundled fiber for adding a hydraulic hardened body, which has improved bundleability when subjected to dry blending with the hydraulic material and is excellent in dispersibility in a slurry; a premix cement composition and the hydraulic hardened body containing the same; and a method for producing the same.SOLUTION: This invention relates to a bundled fiber for adding a hydraulic hardened body, in which a plurality of single fibers are bundled with a sizing agent, wherein: 1.0 mass% or more of the sizing agent based on a fiber mass is adhered to the bundled fiber; and the sizing agent contains a sulfosuccinate salt. This invention further relates to a premix cement composition and the hydraulic hardened body, which contain the bundled fiber for adding the hydraulic hardened body. This invention also relates to a method for producing the bundled fiber for adding the hydraulic hardened body, including steps of: imparting a treating liquid of the sizing agent, containing the sulfosuccinate salt, to a tow in which a plurality of single fibers are bundled; and bundling the plurality of single fibers by drying the tow to adjust the amount of sizing agent adhered to be 1.0 mass% or more based on the fiber mass.SELECTED DRAWING: None

Description

The present invention, cement, can be added to hydraulic materials such as mortar, hydraulically hardened body addition focusing fiber that can be suitably used particularly premix cement composition, premix cement composition containing it and The present invention relates to a hydraulically cured product and a method for producing the same.

Conventionally, it has been proposed to use various inorganic fibers and synthetic fibers as a reinforcing fiber for cement, which is an alternative to asbestos, particularly for mortar. Since it is difficult to obtain a sufficient reinforcing effect by clinging to the aggregate, the use of thick monofilament has been devised to prevent clinging to the aggregate when mixed with the cement material. However, if thick fibers are used, the trowel coatability will deteriorate, so in recent years, when thin fibers are joined and bundled to form so-called bundled fibers, when mixed with cement for mortar and fine aggregate and then water is added and stirred. Focused fibers are used to separate the focused fibers and thereby reinforce the mortar (hardened cement).

For example, Patent Document 1 describes a cement-reinforcing bundled fiber in which single fibers are bundled with a water-soluble sizing agent. Patent Document 2 describes a cement-reinforcing bundled fiber in which fibers of parallel fiber aggregates are bonded and bundled with a water-insoluble sizing agent. Patent Document 3 describes a cement-reinforcing bundled fiber in which short-cut fibers to which a normal-alkyl phosphate alkali metal salt having 8 to 18 carbon atoms is adhered and bundled.

JP, 7-309650, A JP-A-8-12391 JP, 7-2554, A

However, the cement-reinforcing bundled fibers described in Patent Documents 1 and 2 have insufficient dispersibility in the slurry, and further improvement is required. The cement-reinforcing bundled fibers described in Patent Document 3 have poor bundleability when dry-mixed with a cement material, and further improvement is required.

The present invention, in order to solve the above-mentioned conventional problems, improves the focusing property when mixed with a hydraulic material such as cement by dry mixing, and the hydraulically cured product-added focusing fiber having good dispersibility in the slurry, Provided are a premix cement composition containing the same, a hydraulic set, and a method for producing the same.

The present invention is a bundled fiber in which a plurality of single fibers are bundled with a bundled agent, wherein the bundled fiber has 1.0% by mass or more of a bundled agent attached to the fiber mass, The agent relates to a bundled fiber for adding a hydraulically hardened material, which comprises a sulfosuccinate salt.

The present invention also relates to a cement, and a premix cement composition comprising the above-mentioned sizing fiber for adding a hydraulically set material.

The present invention also relates to a hydraulic set, which comprises a cement and the above-mentioned bundled fibers for adding the set hydraulic set.

The present invention is also a method for producing the above-mentioned hydraulically cured product-added bundled fibers, wherein a plurality of single fibers are bundled in the tow, and a treatment liquid of a sizing agent containing a sulfosuccinate salt is applied, Bundling for adding a hydraulic cured product, which includes a step of drying the tow and adjusting the attached amount of the sizing agent to 1.0% by mass or more with respect to the mass of the fiber to bundle a plurality of single fibers. The present invention relates to a fiber manufacturing method.

According to the present invention, the focusing property when dry-mixed with a hydraulic material such as cement is improved, and the hydraulically hardened product-added focusing fiber having good dispersibility in the slurry, and a premixed cement containing the same A composition and a hydraulically cured product can be provided. Further, according to the production method of the present invention, the focusing property when dry-mixed with a hydraulic material such as cement is improved, and it is possible to obtain a hydraulically hardened body-added focusing fiber having good dispersibility in the slurry. ..

FIG. 1 is a schematic diagram of a fiber cross section of a single fiber that constitutes a bundled fiber according to one or more embodiments of the present invention. FIG. 2 is a schematic diagram illustrating each dimension of a convex portion of a single fiber that constitutes a bundled fiber according to one or more embodiments of the present invention. FIG. 3 is a scanning electron micrograph (100×) of the cross section of the bundled fibers of Example 1. FIG. 4 is a scanning electron micrograph (100×) of the cross section of the bundled fibers of Example 4. FIG. 5 is a photograph showing the shape of a solvent extraction stainless steel column.

The present inventor, in order to solve the above-mentioned conventional problems, as a result of diligent studies, in a hydraulically cured product-added sizing fiber in which a plurality of single fibers are bundled with a sizing agent, a sizing agent containing a sulfosuccinate salt is used. By using the sizing agent by adhering the sizing agent to the sizing fiber in an amount of 1.0% by mass or more with respect to the fiber mass, the sizing property of the sizing fiber when dry mixed with a hydraulic material such as cement is improved. It was found that the dispersibility of the bundled fibers in the slurry is good.

In the bundling fiber, the single fibers are at least partially bonded to each other with a bundling agent containing a sulfosuccinate salt. It is preferable that the sizing agent contains a sulfosuccinate salt, and the sulfosuccinate salt has a property of becoming a semi-solid state in a dry state, and such a sizing fiber has a high sizing property in a dry state and can be dry-mixed. It is presumed that the premix cement composition retains its sizing property even when prepared. Further, the sizing agent contains a sulfosuccinate salt, and the sulfosuccinate salt has excellent penetrability, and preferably has a property of becoming a semi-solid state in a dry state. It is presumed that the dispersability of the bundled fibers in the slurry is also good. The bundled fiber can be suitably used for the premix cement composition because it has high sizing property in a dry state and high dispersibility in water.

The sulfosuccinate salt is a dialkyl sulfosuccinate salt, and (polyoxyalkylene) from the viewpoint of further improving the focusing property in a dry state and during dry mixing, and further improving the dispersibility in water and the dispersibility in a slurry. It is preferably one or more selected from the group consisting of alkyl sulfosuccinate salts, and more preferably dialkyl sulfosuccinate salts.

Examples of the (polyoxyalkylene) alkyl sulfosuccinate salt include an alkyl sulfosuccinate salt or an alkyl sulfosuccinate salt having a polyoxyalkylene chain added. Examples of the alkyl sulfosuccinate salt include disodium alkyl sulfosuccinate and sodium alkyl allyl sulfosuccinate. As the polyoxyalkylene alkyl sulfosuccinate salt, when the polyoxyalkylene chain is a polyoxyethylene chain, for example, polyoxyethylene lauryl disodium sulfosuccinate, polyoxyethylene lauroyl ethanolamide disodium sulfosuccinate, polyoxyethylene alkyl Examples include disodium sulfosuccinate and the like.

The dialkyl sulfosuccinate salt is a dialkyl ester of succinic acid having a sulfonate group at the α-position. In the above-mentioned dialkyl sulfosuccinate salt, the carbon number of the alkyl group is 4 or more from the viewpoint of further improving the dry state of the bundled fiber and the bundleability during dry mixing, and further improving the dispersibility in water and the dispersibility in the slurry. It is preferably 22 or less, more preferably 5 to 20 carbon atoms in the alkyl group, further preferably 6 to 18 carbon atoms in the alkyl group, and 7 to 16 carbon atoms in the alkyl group. The following is particularly preferable. The alkyl group may be linear or branched, and the two alkyl groups may be the same or different. Examples of the sulfonate include alkali metal salts such as sodium salt and potassium salt, alkaline earth metal salts such as calcium salt and magnesium salt, ammonia salt, amine salt and the like. Among them, alkali metal salts are preferable, and sodium salts are more preferable.

Specific examples of the dialkylsulfosuccinate salt include dihexylsulfosuccinic acid sodium salt, di-2-ethylhexylsulfosuccinic acid sodium salt, dioctylsulfosuccinic acid sodium salt, dilaurylsulfosuccinic acid sodium salt, ditridecylsulfosuccinic acid sodium salt, Examples thereof include dimyristyl sulfosuccinic acid sodium salt and distearyl sulfosuccinic acid sodium salt. These dialkyl sulfosuccinate salts may be used alone or in combination of two or more. From the viewpoints of further improving the focusing property in the dry state and during dry mixing, and further improving the dispersibility in water and the dispersibility in the slurry, the dialkyl sulfosuccinate salt is preferably dioctyl sulfosuccinic acid sodium salt.

In the bundled fiber of the present invention, it is preferable to attach a sizing agent having a high staying power in a bundled state, and the storage shear modulus G′ of the sulfosuccinate salt is preferably 0.04 MPa or more and 4.0 MPa or less. , 0.07 MPa or more and 2.0 MPa or less are more preferable, and 0.1 MPa or more and 1.0 MPa or less are particularly preferable. If the storage shear modulus G'is too small, the single fibers are likely to be disaggregated from the fiber bundle during production or when premixed with cement, which may reduce the durability of the bundled state. On the other hand, if the storage shear modulus G'is too large, the sizing agent component attached to the fibers may crack when the moisture brought in is dried in the manufacturing process, and it may not be possible to maintain the fiber bundled state.

In the bundled fiber of the present invention, it is preferable to attach a sizing agent having a high staying power in a bundled state, and the sulfosuccinate salt is a ratio of loss shear modulus and storage shear modulus in dynamic viscoelasticity measurement. The loss tangent tan δ is preferably 0.05 or more and 5.0 or less, more preferably 0.1 or more and 2.0 or less, and particularly preferably 0.3 or more and 1.0 or less. If the loss tangent tan δ is too small, it becomes difficult for the sulfosuccinate salt to follow deformation, and the interface between the fiber and the sulfosuccinate salt is likely to peel off. On the other hand, if the loss tangent tan δ is too large, the sulfosuccinate salt may flow due to its own weight during production or storage and may be separated from the fiber. In particular, when the loss tangent tan δ is 0.3 or more and 1.0 or less, the sulfosuccinate salt has appropriate elasticity and viscosity, so that the focusing property in a dry state becomes high. The loss tangent is determined by dynamic viscoelasticity measurement under the condition of a frequency of 1 Hz/deg to obtain G′ (storage shear elastic modulus (Pa)) and G″ (loss shear elastic modulus (Pa)). Tan δ (loss tangent (vibration absorption coefficient)) was calculated as follows.
tan δ (loss tangent (vibration absorption count)) = G"/G'

In the bundled fiber of the present invention, it is suitable to attach a sizing agent having a high staying power of the bundled state, and the dynamic viscosity η'in the sulfosuccinate salt is preferably 8 kPa·s or more, and 15 kPa·s. The above is more preferable, and 20 kPa·s or more is particularly preferable. If the dynamic viscosity η'is too small, the single fibers are likely to be disaggregated from the fiber bundle during production or premixing with cement, and the sustaining power of the bundled state may be reduced. Further, when the loss tangent is 1 or more and the viscosity is small, the sulfosuccinate salt may flow by its own weight and may be easily separated from the fiber.

In the bundled fiber of the present invention, it is preferable to attach a sizing agent having a high adhesive force, which is a resistance against the force of separating the single fibers, and the sulfosuccinate salt is measured by a probe tack test. preferably the tensile at maximum stress 100 gf / cm ² or more, and more preferably 400 gf / cm ² or more. Higher energy until the fiber is isolated from the fiber bundle is more suitable for maintaining the bundling property, and the sulfosuccinate salt preferably has a breaking energy of 10 gf·mm/cm ² or more. , 300 gf·mm/cm ² or more is more preferable.

While further improving the dry state of the bundled fibers and the bundleability during dry mixing, from the viewpoint of improving the dispersibility in water and the dispersibility in the slurry, the bundled fibers have a sulfosuccinate salt with respect to the fiber mass. 0.2 mass% or more and 15.0 mass% or less is preferably attached, 0.3 mass% or more and 10.0 mass% or less is more preferable, and 0.35 mass% or more and 5.0 mass% or more It is more preferable that the amount is less than 0.4% by mass, and it is particularly preferable that the amount is less than 0.4% by mass and less than 3.0% by mass.

The sizing agent may include other components in addition to the sulfosuccinate salt. As other components, for example, a water-soluble sizing agent, a water-insoluble sizing agent, a surfactant, etc. can be used within the range that does not impair the effects of the present invention. Examples of the water-soluble sizing agent include corn starch, tapioca, vegetable wheat starch, potato starch, vegetable gums, alpha starch, starch derivative acetate starch, phosphate starch, enzymatic starch, cationized starch, roasted starch, Carboxymethyl starch, carboxyethyl starch, hydroxyethyl starch, positive starch, starch such as cyanoethylated starch and dialdehyde starch, cellulose derivatives such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose and carboxymethyl cellulose, funoli, casein, sodium alginate, polyvinyl alcohol , As well as polyacrylic acid and the like. Examples of the non-water-soluble sizing agent include vinyl acetate type, vinyl acetate-ethylene type, and propylene type. Examples of the surfactant include alkyl phosphate alkali metal salts, polyoxyethylene alkyl phosphate ester salts, higher fatty acid metal salts having 8 to 22 carbon atoms, higher alcohol sulfuric acid ester metal salts, higher alkyl ether sulfuric acid ester metal salts, Examples thereof include metal salts of alkylbenzenesulfonic acid, metal salts of alkylbenzenenaphthalenesulfonic acid, metal salts of paraffinsulfonic acid, alkylamine salts and alkylammonium salts.

The surfactant is preferably an alkyl phosphate alkali metal salt. The alkyl phosphate alkali metal salt can form an ionic bond with calcium ions present in the cement slurry to improve the hydrophilicity of the fiber and the affinity between the fiber and the cement composition. Among them, the normal alkyl phosphate alkali metal salt is preferable because it can maintain the dispersibility because it gives the fiber surface a continuous affinity for cement in the slurry without impairing the focusing property of the sulfosuccinate salt. The normal alkyl phosphate alkali metal salt may be either a monoalkyl ester or a dialkyl ester. In the normal alkyl phosphate alkali metal salt, the alkyl group has preferably 8 or more and 18 or less carbon atoms, and more preferably 10 or more and 18 or less carbon atoms. Examples of the normal alkyl phosphate alkali metal salt include a sodium salt and a potassium salt, and a potassium salt is preferable. Examples of the normal alkyl phosphate alkali metal salt include octyl phosphate potassium salt, octyl phosphate sodium salt, decyl phosphate potassium salt, decyl phosphate sodium salt, lauryl phosphate potassium salt, lauryl phosphate sodium salt, tridecyl phosphate potassium salt, tridecyl. Examples thereof include sodium phosphate, myristyl phosphate potassium salt, myristyl phosphate sodium salt, cetyl phosphate potassium salt, cetyl phosphate sodium salt, stearyl phosphate potassium salt and stearyl phosphate sodium salt.

A polyoxyethylene alkyl phosphate ester salt is also preferable as the surfactant that imparts a continuous affinity for cement to the fiber surface in the slurry and maintains the dispersibility. The polyoxyethylene alkyl phosphate ester salt is preferably one or more compounds selected from the group consisting of a compound represented by the following chemical formula (1) and a compound represented by the following chemical formula (2).
However, in the chemical formula (1), R represents an alkyl group having 2 to 20 carbon atoms, A represents an alkali metal element or an alkaline earth metal element, and n is 1 to 20.
However, in the chemical formula (2), R ₁ and R ₂ represent an alkyl group having 2 to 20 carbon atoms, A represents an alkali metal element or an alkaline earth metal element, and n and m each are 1 to 20.

In the chemical formula (1) or the chemical formula (2), the alkaline earth metal of A is preferably Li, Na, K, Rb or the like. Of these, potassium (K) is preferable. As the polyoxyethylene alkyl phosphate ester salt, a compound represented by the following chemical formula (3) or the following chemical formula (4) is more preferable.
However, in the chemical formula (3), R represents an alkyl group having 2 to 20 carbon atoms, and n is 1 to 20.
However, in the chemical formula (4), R ₁ and R ₂ represent an alkyl group having 2 to 20 carbon atoms, and n and m are 1 to 20 each.

The other components may be used alone or in combination of two or more. Other components are normal alkyl phosphate alkali metal salt and polyoxyethylene alkyl phosphate ester from the viewpoint of further improving the focusing property during dry state and dry mixing, and further improving the dispersibility in water and the dispersibility in slurry. It is preferably one or more phosphorus-based surfactants selected from the group consisting of salts.

It is sufficient for the sizing fiber to have a sizing agent attached to the fiber mass in an amount of 1.0% by mass or more, and the sizing property is not particularly limited, but the sizing property in a dry state and dry mixing is further enhanced, and the dispersibility in water and From the viewpoint of better dispersibility in the slurry, the amount of the sizing agent attached to the fiber mass, specifically, a sulfosuccinate salt, and normal alkyl phosphate alkali metal salt and polyoxyethylene alkyl phosphate ester salt The total amount of one or more phosphorus-based surfactants selected from the group is preferably 1.0% by mass or more, more preferably 1.2% by mass or more, and 1.4% by mass or more. Is more preferable. Further, from the viewpoint of improving the processability at the time of adhering to the bundling fiber, the adhering amount of the sizing agent to the fiber mass, specifically, a sulfosuccinate salt, and a normal alkyl phosphate alkali metal salt and a polyoxyethylene alkyl phosphorus The total amount of one or more phosphorus-based surfactants selected from the group consisting of acid ester salts is preferably 15.0% by mass or less, more preferably 10.0% by mass or less, and 8.0 The content is more preferably not more than mass%, particularly preferably not more than 5.0 mass%, most preferably not more than 3.0 mass%. The bundled fibers are not particularly limited, but depending on the purpose and the like, one or more phosphorus-based surface active agents selected from the group consisting of sulfosuccinate salts and normal alkyl phosphate alkali metal salts and polyoxyethylene alkyl phosphate salts. A sizing agent component other than the agent may be attached to the fiber mass in an amount of 0.2% by mass or more and 3.0% by mass or less.

When the total mass of one or more phosphorus-based surfactants selected from the group consisting of the sulfosuccinate salt, normal alkyl phosphate alkali metal salt and polyoxyethylene alkyl phosphate salt is 100% by mass, the sulfosuccinate salt Is 10% by mass or more and 90% by mass or less, and 10% by mass or more and 90% by mass or less of one or more phosphorus-based surfactants selected from the group consisting of normal alkyl phosphate alkali metal salts and polyoxyethylene alkyl phosphate ester salts. The sulfosuccinate salt is 20% by mass or more and 80% by mass or less, and one or more phosphorus-based surface active agents selected from the group consisting of normal alkyl phosphate alkali metal salts and polyoxyethylene alkyl phosphate ester salts. The agent may be 20% by mass or more and 80% by mass or less; the sulfosuccinate salt is 25% by mass or more and 75% by mass or less, and a group consisting of a normal alkyl phosphate alkali metal salt and a polyoxyethylene alkyl phosphate ester salt. One or more phosphorus-based surfactants selected from may be 25% by mass or more and 75% by mass or less.

From the viewpoint of improving the dispersibility in water and the dispersibility in the slurry while improving the focusing property in a dry state and during dry mixing, the amount of the sizing agent, the sulfosuccinate salt, and the normal alkyl phosphate alkali with respect to the fiber mass are improved. The total deposition amount of the metal salt is preferably 1.0% by mass or more, more preferably 1.2% by mass or more, and further preferably 1.4% by mass or more. Further, from the viewpoint of improving the processability in adhering to the bundled fiber, the adhered amount of the sizing agent, specifically, the total adhered amount of the sulfosuccinate salt and the normal alkyl phosphate alkali metal salt with respect to the fiber mass is 15. It is preferably 0% by mass or less, more preferably 10.0% by mass or less, further preferably 8.0% by mass or less, particularly preferably 5.0% by mass or less, 3 Most preferably, it is not more than 0.0% by mass. The sizing fiber is not particularly limited, but depending on the purpose or the like, other sizing agent components other than the sulfosuccinate salt and the normal alkyl phosphate alkali metal salt are contained in an amount of 0.2% by mass or more and 3.0% by mass or more with respect to the mass of the fiber. It may be attached by mass% or less.

When the total mass of the sulfosuccinate salt and the normal alkyl phosphate alkali metal salt is 100 mass %, the sulfosuccinate salt is 10 mass% to 90 mass %, and the normal alkyl phosphate alkali metal salt is 10 mass %. Or more and 90% by mass or less; sulfosuccinate salt may be 20% by mass or more and 80% by mass or less, and normal alkyl phosphate alkali metal salt may be 20% by mass or more and 80% by mass or less; sulfosuccinate The nate salt may be 25% by mass or more and 75% by mass or less, and the normal alkyl phosphate alkali metal salt may be 25% by mass or more and 75% by mass or less.

From the viewpoint of further improving the focusing property in the dry state and dry mixing, and further improving the dispersibility in water and the dispersibility in the slurry, the amount of the sizing agent attached to the fiber mass, specifically, a sulfosuccinate salt and The total amount of the polyoxyethylene alkyl phosphate ester deposited is preferably 1.0% by mass or more, more preferably 1.2% by mass or more, and further preferably 1.4% by mass or more. .. Further, from the viewpoint of improving the processability when attaching to the bundled fiber, the amount of the sizing agent attached to the fiber mass, specifically, the total amount of the sulfosuccinate salt and the polyoxyethylene alkyl phosphate ester salt attached is It is preferably 15.0% by mass or less, more preferably 10.0% by mass or less, further preferably 8.0% by mass or less, particularly preferably 5.0% by mass or less. Is most preferably 3.0% by mass or less. The sizing fiber is not particularly limited, but depending on the purpose and the like, other sizing agent components other than the sulfosuccinate salt and the polyoxyethylene alkyl phosphate salt are 0.2% by mass or more and 3% by mass or more with respect to the mass of the fiber. It may be attached in an amount of 0.0 mass% or less.

When the total mass of the sulfosuccinate salt and the polyoxyethylene alkyl phosphate ester salt is 100 mass %, the sulfosuccinate salt is 10 mass% or more and 90 mass% or less, and the polyoxyethylene alkyl phosphate ester salt is May be 10% by mass or more and 90% by mass or less; the sulfosuccinate salt is 20% by mass or more and 80% by mass or less, and the polyoxyethylene alkyl phosphate ester salt is 20% by mass or more and 80% by mass or less. The sulfosuccinate salt may be 25% by mass or more and 75% by mass or less, and the polyoxyethylene alkyl phosphate ester salt may be 25% by mass or more and 75% by mass or less.

The hydraulically hardened body-added bundled fibers are not particularly limited, but may be constituted by appropriately using those used as cement reinforcing fibers. For example, polyolefin fibers such as polypropylene, polyethylene and poly-4-methylpentene-1, vinylon fibers, acrylic fibers, polyamide fibers, aramid fibers, carbon fibers, glass fibers and the like can be appropriately used. A polyolefin fiber having excellent alkali resistance can be preferably used.

The polypropylene is not particularly limited, but the isotactic pentad fraction (IPF: mol %) is preferably 90% or more, more preferably from the viewpoint that a high-strength fiber can be obtained in terms of stereoregularity. 93% or more, and more preferably 94% or more of polypropylene can be used. It should be noted that the IPF may be measured for the n-heptane-insoluble component according to “Macromolecules” (Macromolecule, Vol. 6, 925 (1973) and Macromolecule, Vol. 8, 687 (1975)).

The polypropylene is not particularly limited, but it is preferable that the Q value (Mw/Mn) is less than 6, since it has high drawability and high strength fiber can be obtained. A more preferable Q value is less than 5, and further preferably 4 or less.

The single fiber constituting the bundled fiber may be a composite fiber. Specifically, it may be any of a core-sheath type composite fiber, an eccentric core-sheath type composite fiber, a side-by-side type composite fiber, a split type composite fiber and a sea-island type composite fiber. For example, in the case of the core-sheath type composite fiber, the outer shape is multilobed, and the core component may be circular or irregular. When the core component has an irregular shape, it is preferable that the core component has a shape substantially similar to the external shape. Both components, for example, both the sheath component and the core component are preferably polyolefin resins, and more preferably polypropylene, polymethylpentene, or a mixture of polypropylene and polymethylpentene.

In the bundled fiber, the cross-sectional shape of the single fiber may be any of a circular shape, an elliptical shape, a multilobe shape, a star shape, a flat shape, and the like, but is not particularly limited, but from the viewpoint of a high cement reinforcing effect, it is a multilobe shape. It is preferable to have. Further, in the multi-lobed cross section, a gap is likely to be generated between fibers, but during dry mixing, the sulfosuccinate salt, which is a focusing component, can maintain the bundling property, and during the slurry mixing, moisture can be retained on the fiber side surface between the fibers. It is presumed that the sulfosuccinate salt is released from the sticking because it is easily held and the water permeability is improved. Specifically, the cross-sectional shape of the single fiber constituting the bundled fiber has 3 or more and 16 or less convex portions, preferably 3 or more and 8 or less convex portions, and particularly preferably 3 It has not less than 5 and not more than 5 convex portions. Examples of the multi-leaf shape include three-leaf having three convex portions, four-leaf having four convex portions, eight-leaf having eight convex portions, and the like. By using a fiber having a multi-lobed cross section in which the number of convex portions satisfies the above range, the area in contact with the cement particles, the coarse aggregate and the fine aggregate is increased, and the cement reinforcing effect is enhanced. Further, in the multilobe cross-sectional shape, it is preferable that the convex portions are radially formed from the vicinity of the center of the fiber. By forming the protrusions radially, the cement particles easily enter between the adjacent protrusions, the cross-linking between the cement particles is strengthened, and the cement reinforcing effect is enhanced. Examples of the multi-lobed cross-sectional shape in which the convex portions are radially formed include a four-lobed shape shown in FIG. 1A and an eight-lobed shape shown in FIG. 1B. There are two types of fiber cross sections: a fiber cross section cut into a plane perpendicular to the longitudinal direction of the fiber and a fiber cross section cut into a plane parallel to the longitudinal direction of the fiber. In the present invention, unless otherwise specified, the fiber cross section refers to a cut surface cut to be a plane perpendicular to the longitudinal direction of the fiber, and the cross-sectional shape is perpendicular to the longitudinal direction of the fiber. It refers to the shape of the cut surface that is cut so that it becomes a flat surface.

In the at least one convex portion existing in the fiber cross section, it is preferable that the tip portion is substantially curved and the width of the root portion toward the center of the fiber is smaller than the maximum width of the tip portion. More preferably, in all the convex portions existing in the fiber cross section, the tip end portion is substantially curved, and the width of the root portion toward the center of the fiber is smaller than the maximum width of the tip end portion. By having such a shape, it is easy to deform from the root, and the cement particles contained in the cement hardened body easily enter the concave portion between the adjacent convex portions. As shown in FIG. 2, the maximum width of the tip portion of the convex portion is obtained by drawing a line connecting the midpoint u of the line connecting the two roots of the convex portion to the tip (vertex t) of the convex portion. It means the maximum length D when a perpendicular line is drawn from the line toward the outer shape of the convex portion, and the width of the root portion of the convex portion in the fiber cross section is the two roots of the convex portion as shown in FIG. It means the length W of the connecting line. In the convex portion, the ratio (D/W) of the maximum width D of the tip portion and the width W of the root portion is preferably 1.1 or more and 4.0 or less, more preferably 1.3 or more and 3. It is 0 or less, particularly preferably 1.4 or more and 2.4 or less, and most preferably 1.5 or more and 2.0 or less. When D/W satisfies the above range, the maximum width of the tip portion of the convex portion becomes larger than the width W of the root portion of the convex portion at a constant rate, so that the cement particles and the particle diameter inside the cement hardened body are increased. Since it becomes difficult for the convex portions of the fibers that have bitten between the small aggregates to pull out, the crosslinking of the fibers is strengthened. The maximum width of the tip portion of the convex portion and the width of the root portion of the convex portion can be obtained by enlarging the fiber cross section of the fiber bundle with an electron microscope or the like and averaging the values of five arbitrary fibers.

The maximum width D of the tip portion of the convex portion is preferably 3 μm or more and 45 μm or less. It is more preferably 5 μm or more and 35 μm or less, still more preferably 6 μm or more and 30 μm or less, and particularly preferably 7 μm or more and 28 μm or less. Within the above range, cement particles or aggregates having a small particle diameter easily enter the concave portions formed between the adjacent convex portions, and in the cement hardened body, the added fibers become difficult to pull out, and an excellent locking effect Easy to exert (anchor effect).

The width W of the root portion of the convex portion is preferably 1.5 μm or more and 32 μm or less. It is more preferably 2 μm or more and 26 μm or less, still more preferably 2.5 μm or more and 23 μm or less, and particularly preferably 3.5 μm or more and 18 μm or less. When the width W of the root portion of the convex portion is within the above range, cement particles or aggregates having a small particle diameter are likely to enter the concave portions formed between the adjacent convex portions, and the fibers are difficult to pull out. Further, when the width W of the root portion is within the above range, a part of the convex portions tends to be easily peeled off from the vicinity of the root, fibrillated, or separated due to the shearing force generated by mixing during the slurry preparation. , Easy to improve dispersibility.

The length of the convex portion in the fiber cross section is, as shown in FIG. 2, the length of the line connecting the midpoint u of the line connecting the two roots of the convex portion to the tip (vertex t) of the convex portion. Denote by L. In the single fiber constituting the bundled fiber, it is preferable that the ratio L/S of the length L of the convex portion to the maximum passing length S when viewed in the fiber cross section is 0.3 or more and 0.48 or less, It is more preferably 0.35 or more and 0.45 or less, and particularly preferably 0.38 or more and 0.42 or less. By using a fiber having a multilobe cross section satisfying the above range, not only the area of contact with cement particles, coarse aggregate and fine aggregate is increased, but also because the concave portion formed between adjacent convex portions becomes deeper, The cross-linking effect of the fibers, especially the cross-linking strengthening by increasing the contact area between the fibers and the cement particles, is promoted.

In the monofilament constituting the bundled fiber, the length L of the convex portion is preferably 2 μm or more and 70 μm or less, more preferably 4 μm or more and 60 μm or less, and further preferably 6 μm or more and 50 μm or less, and most preferably It is preferably 8 μm or more and 40 μm or less. When the length L of the convex portion is 2 μm or more, the convex portion is easily deformed from the root. When the length L of the convex portion is 70 μm or less, the concave portion formed between the adjacent convex portions is not blocked by the deformed convex portion, cement particles or the like easily enter the concave portion, and the fiber is difficult to pull out. .. The length L of the convex portion can be obtained by enlarging the fiber cross section of the fiber bundle with an electron microscope or the like and averaging the values of 5 arbitrary fibers.

The ratio (L/W) of the length L of the convex portion to the width W of the root portion of the convex portion is preferably 1.0 or more and 5.0 or less, more preferably 1.2 or more. It is 5 or less, more preferably 1.5 or more and 4.0 or less, particularly preferably 1.7 or more and 3.8 or less, and most preferably 1.8 or more and 3.5 or less. When L/W satisfies the above range, the convex portions are easily deformed from their roots without closing the concave portions formed between the adjacent convex portions, so that the fibers in the cement hardened material are firmly attached to the cement particles. Since the fibers are locked with each other and become difficult to pull out, the cross-linking of the fibers is strengthened.

In the single fiber constituting the bundled fiber, the convex portion existing in the fiber cross section may be continuous or discontinuous with respect to the length direction (fiber side surface) of the fiber, but the manufacturing processability is taken into consideration. Then, it is preferable that the convex portions are continuously present on the fiber side surface.

The strength (single fiber strength) of the bundled fibers measured according to JIS L 1015 is preferably 2 cN/dtex or more, and more preferably 3 cN/dtex or more. The preferable upper limit is 20 cN/dtex or less. Within such a range, the bending strength of the hardened cement will be improved. Further, fiber balls (fiber lumps) are less likely to be formed during stirring with a hydraulic material such as cement.

The bundled fibers preferably have a single fiber elongation (breaking elongation) measured according to JIS L 1015 of 15% or more and 160% or less, and more preferably 20% or more and 120% or less. Within such a range, the impact strength of the hardened cement will be improved. In addition, the hardened cement does not easily crack.

The fineness of the single fiber constituting the bundled fiber is not particularly limited, but is preferably 0.5 dtex or more and 30 dtex or less, more preferably 0.8 dtex or more and 20 dtex or less, and further preferably 1.0 dtex or more and 6 dtex or more. It is as follows. When the fineness is within the above-mentioned range, the sizing agent facilitates bundling and the dispersibility in the slurry becomes good.

Although there is no particular limitation on the bundled fiber, the number of single fibers is preferably 10 or more, and more preferably 20 or more, from the viewpoint of further improving the bundleability in a dry state and during dry mixing. In the above-mentioned bundled fibers, the number of single fibers is preferably 4500 or less, and more preferably 3000 or less, from the viewpoint of further enhancing dispersibility in water and dispersibility in slurry, although not particularly limited. preferable.

The bundled fiber has a total fineness of 20 dtex or more and 10000 dtex or less, preferably 40 dtex or more and 6000 dtex or less. When the total fineness is within the above range, the fiber bundles are not entangled with each other during storage or transportation, and do not become lumps or fiber balls.

The sizing fiber is not particularly limited, for example, by applying a treatment liquid of a sizing agent containing a sulfosuccinate salt to a tow in which a plurality of single fibers are bundled and then drying, the adhesion amount of the sizing agent is the fiber mass. Can be produced by bundling the single fibers with a sizing agent by adjusting the content to be 1.0% by mass or more.

The tow can be obtained, for example, by spinning a thermoplastic resin. For example, first, one or more thermoplastic resins such as polyolefin are used, and a single-type or a composite-type nozzle whose cross-sectional shape is a predetermined shape is used to melt the resin, for example, polypropylene. In that case, melt-spinning can be performed at a spinning temperature of 200° C. or higher and 350° C. or lower, and can be taken out at a take-up speed of 100 m/min or more and 1500 m/min or less to obtain a spun filament. In addition, in the above, if necessary, inorganic particles and the like are mixed with the thermoplastic resin, preferably the thermoplastic resin that serves as the sheath component.

The spun filament is then optionally stretched. The stretching temperature is appropriately set depending on the type of thermoplastic resin. For example, when the thermoplastic resin is polypropylene, it is preferable that the stretching temperature is 80° C. or more and 160° C. or less and the stretching ratio is 1.5 times or more and 8 times or less. A more preferable stretching temperature is 110°C or higher and 155°C or lower. A more preferable stretching ratio is 3 times or more and 6 times or less. The stretching method is not particularly limited, wet stretching in which stretching is performed while heating with a high temperature liquid such as high temperature hot water, dry stretching in which stretching is performed while heating in a high temperature gas or a high temperature metal roll, 100° C. The stretching treatment can be carried out by a known method such as steam stretching in which the fibers are stretched while heating the fibers under the atmospheric pressure or the pressurized state. The stretching process may be performed in one stage or in a so-called multistage stretching process performed in a plurality of stages. The obtained drawn filament (multifilament) may be used as it is as a tow, or if necessary, a plurality of drawn filaments may be bundled and used as a tow.

The treatment liquid for the sizing agent is not particularly limited as long as it contains a sulfosuccinate salt as a sizing agent, and may be, for example, an aqueous solution containing only a sulfosuccinate salt as a sizing agent. May be an aqueous solution containing one or more phosphorus-based surfactants selected from the group consisting of sulfosuccinate salts and normal alkyl phosphate alkali metal salts and polyoxyethylene alkyl phosphate salts, and sulfosuccinate as a sizing agent It may be an aqueous solution containing a salt and an alkali metal salt of normal alkyl phosphate, or an aqueous solution containing a sulfosuccinate salt and a polyoxyethylene alkyl phosphate ester salt as a sizing agent.

The mixing ratio of the sulfosuccinate salt and the phosphorus-based surfactant may be 10/90 or more and 90/10 or less in a mass ratio (sulfosuccinate salt/phosphorus-based surfactant). The above may be 85/15 or less, 20/80 or more and 80/20 or less, or 25/75 or more and 75/25 or less.

The mixing ratio of the sulfosuccinate salt and the normal alkyl phosphate alkali metal salt may be 10/90 or more and 90/10 or less in a mass ratio (sulfosuccinate salt/normal alkyl phosphate alkali metal salt). It may be /85 or more and 85/15 or less, 20/80 or more and 80/20 or less, or 25/75 or more and 75/25 or less.

The mixing ratio of the sulfosuccinate salt and the polyoxyethylene alkyl phosphate ester salt is 10/90 or more and 90/10 or less in a mass ratio (sulfosuccinate salt/polyoxyethylene alkyl phosphate ester salt). 15/85 or more and 85/15 or less, 20/80 or more and 80/20 or less, or 25/75 or more and 75/25 or less.

In addition, the treatment liquid of the sizing agent is, in accordance with the purpose or the like, other sizing agents described above in addition to a sulfosuccinate salt and a normal alkyl phosphate alkali metal salt and/or a polyoxyethylene alkyl phosphate ester salt as a sizing agent. It may be an aqueous solution containing the components.

The method of applying the treatment liquid of the sizing agent is not particularly limited, and may be any method such as a dipping method, a spraying method, or a coating method. After applying the treatment liquid for the sizing agent, in particular, after applying the treatment liquid for the sizing agent by the dipping method, it can be squeezed with a mangle roll, if necessary.

The drying is not particularly limited as long as it can be adjusted so that the amount of the sizing agent attached is 1.0% by mass or more with respect to the fiber mass. For example, it can be performed at a temperature of 60° C. or higher and 140° C. or lower for 5 minutes or longer and 120 minutes or shorter.

After the drying step, the bundled fibers are cut into a predetermined fiber length, if necessary. For example, the fiber length of the bundled fibers may be 2 mm or more and 50 mm or less, 3 mm or more and 30 mm or less, or 5 mm or more and 20 mm or less. When the fiber length is within the above range, the miscibility when mixing with a hydraulic material such as cement and stirring is good.

The bundled fibers may be dry mixed with cement to be used as a premix cement composition. When used for mortar, the premix cement composition may include cement, fine aggregate, and the bundled fibers. When used for concrete, the premix cement composition may include cement, fine aggregate, coarse aggregate, and the bundled fibers. If desired, functional agents such as an admixture may be added to the premix cement composition. As the cement, various cements such as normal Portland cement, early strength Portland cement, super early strength Portland cement, moderate heat Portland cement, low heat Portland cement and sulfate resistant Portland cement can be used. Quartz sand, river sand, sea sand, beach sand or the like can be used as the fine aggregate, and crushed stone or the like can be used as the coarse aggregate. Examples of the admixture include an AE agent, an AE water reducing agent, a highly functional AE water reducing agent, a fluidizing agent, a curing accelerator, a rust preventive, a setting retarder, a quick setting agent, and a shrinkage reducing agent. These admixtures can be appropriately selected and used according to the purpose and application.

The premix cement composition is not particularly limited, but for example, when the total mass of the premix cement composition is 100 mass %, the bundled fibers may include 0.05 mass% or more and 6.0 mass% or less. , 0.3 mass% or more and 3.0 mass% or less may be contained.

By adding an appropriate amount of water to the premix cement composition and thoroughly kneading the mixture to obtain a slurry, it is possible to obtain a hardened cement (hydraulic hardened body) such as mortar or concrete. In the premix cement composition, since the sizing properties and the water permeability of the sizing fibers are high, the fiber lumps are not formed in the slurry, the sizing fibers are scattered, and the dispersibility is high. In the hydraulically hardened body, for example, in the hydraulic material that is hardened by a hydration reaction such as concrete, mortar, and cement paste, the focusing fibers are added and dispersed because the fibers are dispersed. Highly effective for reinforcement by fibers and loose fibers.

Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to the examples below.

The measurement method and evaluation method used in the examples will be described.

(Dynamic viscoelasticity measurement)
The dynamic viscoelasticity was measured by using a dynamic viscoelasticity measuring device (Rheosol-G3000 manufactured by UBM) in a room temperature (20±2° C.) room at 140° C. for 5 hours, and the mass of sulfosuccinate was about 1 g. The salt was sandwiched between parallel plates (material: SUS) having a diameter of 20 mm, and the thickness was 1 mm (however, in the case of polyoxyethylene alkyl (C12-14) disodium sulfosuccinate, it was difficult to deform, so the thickness was set to 2 mm. ) Is measured under the condition of a frequency of 1 Hz/deg, G'(storage shear modulus (Pa)), G" (loss shear modulus (Pa)), and η'(dynamic). Dynamic viscosity (kPa·s)) was calculated, and tan δ (loss tangent (vibration absorption coefficient)) was calculated by the following formula.
tan δ (loss tangent (vibration absorption count))=G″/G′

(Adhesive force measurement (probe tack test))
A sulfosuccinate salt dried at 140° C. for 5 hours was placed on a sample table in a room temperature (20±2° C.) room using a probe-type adhesive force measuring device (Tack Tester TA500 manufactured by UBM). The sample was adjusted so that the sulfosuccinate salt had a thickness of about 5 mm in the flattened state, and a probe having a tip diameter of 5 mm was pressed against the sample of the sulfosuccinate salt at a speed of 0.1 mm/sec, After a load of 200 gf/cm ² was held for about 20 seconds, the tensile stress when the probe was raised at a speed of 0.1 mm/sec was measured and defined as the maximum tensile stress. The breaking energy was calculated by setting the amount of elongation until the tensile stress of the probe was 1 gf/cm ² or less as the test end point and integrating the tensile stress up to that point with the elongation.

(Fineness, strength and elongation)
It was measured according to JIS L 1015.

(Adhesion water content)
It was measured according to JIS L 1015 except that the sample was about 2 to 2.5 g.

(Amount of sizing agent)
The bundled fibers were loosened by hand and then weighed 4 g to prepare a sample. The sample was placed in a stainless steel column for oil extraction, and 10 mL of methanol was added. Two minutes later, the extraction liquid was squeezed out by pistoning the extraction container with an air cylinder for 10 minutes, and the extraction liquid flowing out from the outlet was received by a stainless steel dish. The mass of the stainless dish before receiving the extract was W0. Then, the stainless steel dish containing the extract was heated with a heater at 150° C. to evaporate the methanol component, and then cooled at room temperature (23° C.) for 2 minutes. Then, the mass (W1) of the stainless steel dish after evaporating the methanol component was measured, and the mass (W1-W0) of the increased amount was divided by the fiber mass to calculate a value, and the average value calculated twice The adhesion amount (mass %) of the sizing agent to the fiber mass was defined as A stainless steel column having a shape shown in FIG. 5 is used as the oil agent extraction stainless steel column. The total length of the column is 133.3 mm, the outer diameter is 21.5 mm, the inner diameter is 15.9 mm, and the conical tip (outlet) Part) had a length of 13.0 mm, and the outlet hole diameter was 1.6 mm.

(Amount of sizing agent (a sizing agent containing polyoxyethylene alkyl (C12-14) sulfosuccinic acid disodium salt))
The bundled fibers were loosened by hand and then weighed 4 g to prepare a sample. The sample was placed in a stainless steel column for extracting an oil solution, and 10 mL of boiling water was added. Two minutes later, the extraction liquid was squeezed out by pistoning the inside of the extraction container with an air cylinder for about 3 minutes, and the extraction liquid flowing out from the outlet was received by a stainless steel dish having a mass W0. Then, the cotton was taken out once, disentangled, put again in the stainless steel column, about 5 ml of boiling water was added, and after 2 minutes, the piston was made to act for 10 minutes by the air cylinder. Then, the stainless dish containing the extract was heated with a heater at about 150° C. to evaporate the water content, and then cooled at room temperature (23° C.) for 2 minutes. The mass (W1) of the stainless steel dish after evaporation of water was measured, and the increased mass (W1-W0) was divided by the fiber mass to calculate a value, which was calculated as the adhesion amount (mass %) of the sizing agent to the fiber mass. did.

(Dispersion property of bundled fiber in water)
Water is poured into a water tank (width 57 cm x thickness 18 cm x water surface height 43 cm), the bundled fibers cut to have a fiber length of 6 mm are put in from above, and the stirring blade is rotated at 4000 rpm for 1 minute, and then dispersed in water. The property was visually confirmed and evaluated according to the following criteria.
A: Dispersed in water, almost no floating seeds were formed.
B: Although dispersed in water, there are floating seeds, and the single fibers are scattered.
C: Although dispersed in water, there are floating seeds, and some of them are bundled.
D: Some of the fibers dispersed in water are bundled.
E: It does not disperse in water and remains as a bundle.

(Evaluation of sizing property of sizing fiber 1)
The sizing property of the sizing fiber was evaluated based on the appearance according to the following criteria.
A: A plurality of single fibers are bundled into one.
B: Most of the plurality of single fibers are bundled.
C: Half or more of a plurality of single fibers are bundled.
D: A part of a plurality of single fibers is bundled.
E: The single fibers are scattered.

(Evaluation of sizing property of bundling fiber 2)
The sizing property of the sizing fiber was evaluated based on the hardness according to the following criteria.
A: The gluing is effective and it is crisp, and even if the bundled fibers are lightly rubbed with a finger, it does not dissipate further.
B: Gluing is effective and it is crisp, but when the focusing fibers are lightly rubbed with a finger, a part of the fibers comes apart.
C: Gluing is effective and it is crisp, but if you rub the bundled fibers gently with your fingers, more than half will come apart.
D: The gluing is weakened, and when the bundling fibers are lightly rubbed with a finger, some of them are separated. E: The gluing is weakened, and more than half of the fibers are separated by gently rubbing the bundled fibers with a finger.

(Bundling property of bundling fiber in premix cement composition)
The sizing properties of the sizing fibers in the premix composition were evaluated by a dry mix test. Specifically, 333 g of cement (ordinary Portland cement) and 1000 g of fine aggregate (river sand) were placed in an omni mixer having a capacity of 10 L and stirred at 250 rpm for 1 minute, and then 1.33 g of a bundled fiber having a fiber length of 6 mm was added thereto. (0.1% by mass relative to the total mass of cement and fine aggregate) was added and stirred at 250 rpm for 10 seconds. The obtained premix cement composition was photographed with a camera and observed, and the sizing properties of the sizing fiber were evaluated according to the following criteria.
A: All fibers are kept in a bundle.
B: Half or more of the fibers remain bundled, but some of them are scattered into single fibers.
C: Some fibers are in a bundle shape, and about half (50%) are scattered into single fibers.
D: Some fibers are bundled, and about 75% are scattered into single fibers.
E: Most of the fibers are scattered into single fibers.

(Dispersibility of the bundled fibers in the mortar state)
60 g of water was added to 300 g of the premix cement composition obtained in the same manner as in the evaluation of the sizing property of the sizing fiber in the premix cement composition (W/C=80%, S/C=300%), Knead the mixture for 30 seconds at 250 rpm with an omni mixer, place it in a 4×16 cm mold, leave it in the air at room temperature (23° C.) for 24 hours, and then hit the molded body with a hammer to cut the cross section. It was observed and the dispersibility was evaluated according to the following criteria. In addition, W/C is a mass ratio of cement/water, and S/C is a mass of fine aggregate/cement.
A: The bundled fibers are dispersed and dispersed without forming fiber lumps.
B: Fiber lumps are present.

(Example 1)
<Production of tow>
A polypropylene resin (manufactured by Nippon Polypro Co., Ltd., trade name SA01A) was prepared. This resin was melt-extruded at a spinning temperature of 275° C. using a spinning nozzle having a four-leaf type nozzle hole shape to prepare a spun filament (unstretched yarn) having a single fiber fineness of 7.6 dtex. Then, the spun filament was dry drawn at 140° C. to 3.00 times to obtain a polypropylene fiber having a single fiber fineness of 2.57 dtex. The obtained polypropylene fiber has a four-lobed fiber cross-sectional shape with four convex portions, and the convex portion has a substantially curved tip portion, and the width of the root portion toward the center of the fiber is the maximum width of the tip portion. It was smaller than. The maximum crossover length S when viewed in the fiber cross section is 31.1 μm, the length L of the convex portion is 12.6 μm, the maximum width D at the tip of the convex portion is 10.7 μm, and the width W of the root portion is 5. It was 0.6 μm, L/S was 0.40, D/W was 1.90, and L/W was 2.24.
<Applying sizing agent>
The polypropylene fiber obtained above (tow having a total fineness of 22800 dtex) was treated with dioctyl sulfosuccinate sodium salt (storage shear modulus G′: 0.38 Mpa, loss tangent tan δ: 0.52, dynamic viscosity η′: 31 kPa.・S, maximum tensile stress: 700 gf/cm ² , breaking energy: 954 gf·mm/cm ² ) After immersing in an aqueous solution (treatment solution for sizing agent), squeeze with a mangle roll and dry at 80°C for 5 hours Then, 2.5 mass% of dioctyl sulfosuccinate sodium salt was adhered to obtain a bundled fiber in which polypropylene single fibers were bundled.

(Example 2)
An aqueous solution containing dioctyl sulfosuccinate sodium salt and potassium lauryl phosphate and having a mass ratio of dioctyl sulfosuccinate sodium salt/lauryl phosphate potassium salt of 76.9/23.1 was used as a treatment liquid for the sizing agent, and dioctyl was used. A bundled fiber in which polypropylene single fibers were bundled was obtained in the same manner as in Example 1 except that the total amount of sulfosuccinate sodium salt and potassium lauryl phosphate deposited was 2.69% by mass.

(Example 3)
An aqueous solution containing dioctyl sulfosuccinate sodium salt and potassium lauryl phosphate as a sizing agent treatment solution, wherein the mass ratio of dioctyl sulfosuccinate sodium salt:lauryl phosphate potassium salt is 23.1/76.9, is used. A bundled fiber in which polypropylene single fibers were bundled was obtained in the same manner as in Example 1 except that the total amount of sulfosuccinate sodium salt and potassium lauryl phosphate deposited was 2.39% by mass.

(Example 4)
<Production of tow>
A polypropylene resin (melting point: 168° C., MFR (measurement temperature 230° C., load 2.16 kgf): 8.9 g/10 min) was prepared. This resin was melt-extruded at a spinning temperature of 335° C. using a spinning nozzle having a circular nozzle hole to produce a spun filament (undrawn yarn) having a single fiber fineness of 15.0 dtex. Then, the spun filament was dry-stretched at 150° C. by a factor of 3.82 to obtain a polypropylene fiber having a single fiber fineness of 4.70 dtex.
<Applying sizing agent>
The polypropylene fiber (tow having a total fineness of 2430,000 dtex) obtained above was treated with the same sizing agent treatment solution as in Example 3, so that the total amount of sodium dioctylsulfosuccinate and potassium lauryl phosphate deposited was 1.87 mass. A bundled fiber in which polypropylene single fibers were bundled was obtained in the same manner as in Example 3 except that the content was changed to %.

(Example 5)
A tow of polypropylene fibers having a single fiber fineness of 2.35 dtex was prepared with a draw ratio of 3.20 times, and polyoxyethylene alkyl (C12-14) sulfosuccinic acid disodium salt ( Storage shear modulus G': 1.7 MPa, loss tangent tan δ: 0.20, dynamic viscosity η': 56 kPa·s, maximum tensile stress: 255 gf/cm ² , fracture energy: 18 gf·mm/cm ² ) The polypropylene single fibers were bundled in the same manner as in Example 1 except that the amount of polyoxyethylene alkyl (C12-14) sulfosuccinic acid disodium salt was 2.44% by mass using the aqueous solution containing the polypropylene single fibers. A bundle of fibers was obtained.

(Example 6)
A tow of polypropylene fibers having a single fiber fineness of 2.35 dtex was prepared with a draw ratio of 3.20 times, and polyoxyethylene alkyl (C12-14) sulfosuccinic acid disodium salt and An aqueous solution containing potassium lauryl phosphate and having a mass ratio of polyoxyethylene alkyl (12-14) disodium sulfosuccinate:lauryl phosphate potassium salt of 23.1/76.9 was used, and polyoxyethylene alkyl (12- 14) A bundle of polypropylene single fibers was obtained in the same manner as in Example 1 except that the total amount of sulfosuccinic acid disodium salt and potassium lauryl phosphate deposited was 1.98% by mass.

(Example 7)
A tow of polypropylene fibers having a single fiber fineness of 2.17 dtex was prepared at a draw ratio of 3.40, and 5 mol of dioctyl sulfosuccinate sodium salt and oxyethylene group (POE) were used as a treatment liquid for the sizing agent. An aqueous solution containing polyoxyethylene lauryl phosphate having a carbon chain length of 12 and having a mass ratio of dioctylsulfosuccinate sodium salt/potassium polyoxyethylene lauryl phosphate of 23.1/76.9, A bundled fiber in which polypropylene single fibers were bundled was obtained in the same manner as in Example 1 except that the total amount of dioctylsulfosuccinate sodium salt and potassium polyoxyethylene lauryl phosphate deposited was 2.47% by mass. It was

(Example 8)
A tow of polypropylene fiber having a single fiber fineness of 2.28 dtex was prepared with a draw ratio of 3.40 times, and the total amount of dioctylsulfosuccinate sodium salt and potassium lauryl phosphate deposited was 6.80% by mass. A bundled fiber in which polypropylene single fibers were bundled was obtained in the same manner as in Example 3 except that the above configuration was adopted.

(Example 9)
A tow of polypropylene fibers having a single fiber fineness of 2.28 dtex was prepared with a draw ratio of 3.40 times, and the amount of polyoxyethylene alkyl (C12-14) sulfosuccinic acid disodium salt attached was 7.73 mass. A bundled fiber in which polypropylene single fibers were bundled was obtained in the same manner as in Example 5 except that the content was changed to %.

(Example 10)
A tow of polypropylene fibers having a single fiber fineness of 2.28 dtex was prepared with a draw ratio of 3.40 times, and a total adhesion of polyoxyethylene alkyl (C12-14) sulfosuccinic acid disodium salt and lauryl phosphate potassium salt. A bundled fiber in which polypropylene single fibers were bundled was obtained in the same manner as in Example 6 except that the amount was adjusted to 5.87% by mass.

(Example 11)
A tow of polypropylene fibers having a single fiber fineness of 2.28 dtex was prepared with a draw ratio of 3.40, and the total amount of dioctyl sulfosuccinate sodium salt and potassium polyoxyethylene lauryl phosphate attached was 9.33 mass. A bundled fiber in which polypropylene single fibers were bundled was obtained in the same manner as in Example 7 except that the content was changed to %.

(Comparative Example 1)
As a treatment liquid, an aqueous solution containing a lauryl phosphate potassium salt was used, and except that the amount of the lauryl phosphate potassium salt attached was adjusted to 2.84% by mass, the polypropylene single fiber was focused in the same manner as in Example 1. Fiber was obtained.

(Comparative example 2)
<Production of tow>
A polypropylene resin (manufactured by Nippon Polypro Co., Ltd., trade name SA01A) was prepared. This resin was melt-extruded at a spinning temperature of 275° C. using a spinning nozzle having a four-leaf type nozzle hole shape to prepare a spun filament (unstretched yarn) having a single fiber fineness of 7.6 dtex. Then, the spun filament was dry-drawn at 140° C. by a factor of 3.35 to obtain a polypropylene fiber having a single fiber fineness of 2.65 dtex.
<Applying sizing agent>
As a treatment liquid for the sizing agent, an aqueous solution containing dioctyl sulfosuccinate sodium salt was used, and the concentration of polypropylene single fibers was converged in the same manner as in Example 1 except that the adhesion amount was 0.84% by mass. Fiber was obtained.

(Comparative example 3)
A polypropylene fiber tow having a single fiber fineness of 2.26 dtex was prepared with a draw ratio of 3.23 and a sizing agent treatment liquid containing 5 mol of oxyethylene groups (POE) and a carbon chain length of 12 A polypropylene single fiber was prepared in the same manner as in Example 1 except that an aqueous solution containing a certain potassium polyoxyethylene lauryl phosphate was used so that the amount of the deposited potassium polyoxyethylene lauryl phosphate was 3.29% by mass. A focused fiber bundle was obtained.

The cross sections of the bundled fibers of Examples 1 and 4 were observed with a scanning electron microscope (manufactured by HITACHI, model number “SU3500”), and the results are shown in FIGS. 3 and 4, respectively. From the scanning electron microscope photograph of FIG. 3 (100 times) observing the cross section of the bundled fibers of Example 1, it can be seen that the fibers are bundled and there are gaps between the single fibers in the four-lobed cross section. From this, it is presumed that the fibers of the four-leaf cross section are likely to retain water on the fiber side surfaces between the fibers when the slurry is mixed, and the dispersibility is improved. Although not shown, when the cross sections of the bundled fibers of Examples 2, 3, and 5 to 11 were observed with a scanning electron microscope, it was found that the fibers were similarly bundled and there were gaps between the single fibers. Similarly, from the scanning electron microscope photograph of FIG. 4 (100 times) observing the side surface of the bundled fibers of Example 4, the fibers are bundled in a circular cross section, and there is almost no gap between the single fibers. Recognize.

The dispersibility in water and the sizing property of the bundled fibers obtained in Examples and Comparative Examples were evaluated as described above, and the results are shown in Table 1 below. Further, the sizing properties and dispersibility in the mortar state of the bundled fibers obtained in Examples and Comparative Examples were evaluated as described above, and the results are shown in Table 1 below. The moisture content of the bundled fibers obtained in Examples and Comparative Examples was measured as described above, and the results are shown in Table 1 below. In addition, in Examples and Comparative Examples, the strength and elongation of the polypropylene fibers before applying the sizing agent were measured as described above, and the results are shown in Table 1 below.

As can be seen from Table 1 above, the bundling fibers of Examples 1 to 11 in which the sizing agent containing a sulfosuccinate salt was attached in an amount of 1.0% by mass or more, Comparative Example 1 in which no sulfosuccinate salt was attached, Bundability was improved as compared with the bundling fiber of Comparative Example 2 in which the adhesion amount of No. 3 and the sizing agent was less than 1.0% by mass. Among them, the bundled fibers of Examples 1 to 3 have better sizing properties than the bundled fibers of Examples 5 and 6, and thus it is found that the dialkyl sulfosuccinate salt is particularly preferable as the sizing agent. Since the bundled fibers of Example 3 have better bundleability than the bundled fibers of Example 7, it can be seen that the alkyl phosphate alkali metal salt is more excellent as the surfactant that imparts the affinity for the cement composition. .. The bundled fibers of Examples 8 to 11 are obtained by increasing the adhesion amount of the sizing agent of Example 1 and Examples 5 to 7, and are all bundled as compared with the bundled fibers of Example 1 and Examples 5 to 7. The property was improved and the dispersibility in the mortar state was good. In addition, the bundling fiber of the four-leaf cross section of Examples 1 to 3 to which the sizing agent containing a sulfosuccinate salt is attached by 1.0% by mass or more is the same as the bundling fiber of Comparative Example 1 to which the sulfosuccinate salt is not attached. Compared to Comparative Example 2 in which the premix cement composition had a high sizing property and the amount of the sizing agent attached was less than 1.0% by mass, the dispersibility in a mortar state was excellent. The bundled fibers having a circular cross section of Example 4 had the best bundleability in the premix cement composition as compared with Examples 1 to 3, but the dispersibility in the mortar state was poor. Therefore, the four-leaf cross section has excellent dispersibility because there is a gap between the leaves (projections), while the circular cross-section has few gaps, so that the single fibers adhere to each other and have good convergence. Presumed to be excellent.

Claims (18)

A bundled fiber in which a plurality of single fibers are bundled with a sizing agent,
The sizing fiber has 1.0% by mass or more of a sizing agent attached to the fiber mass,
The sizing agent contains a sulfosuccinate salt, and a sizing fiber for adding a hydraulically cured product. The focused fiber for adding a hydraulically cured product according to claim 1, wherein the sulfosuccinate salt has a maximum tensile stress in a probe tack test of 100 gf/cm ² or more. The water according to claim 1 or 2, wherein the sulfosuccinate salt has a storage shear modulus of 0.04 MPa or more and 4.0 MPa or less and a loss tangent tan δ of 0.05 or more and 5.0 or less in dynamic viscoelasticity measurement. Bundling fiber for addition of hardened material. The said sulfosuccinate salt has a dynamic viscosity in dynamic viscoelasticity measurement of 8 kPa*s or more, The focusing fiber for hydraulically hardening body addition of any one of Claims 1-3. The said sulfosuccinate salt is a dialkyl sulfosuccinate salt, The bundled fiber for hydraulically hardening body addition of any one of Claims 1-4. In the dialkyl sulfosuccinate salt, the bundled fiber for hydraulically hardening body addition according to claim 5, wherein the alkyl group has 4 to 22 carbon atoms. The hydraulically cured product according to any one of claims 1 to 6, wherein a sulfosuccinate salt is attached to the bundled fibers in an amount of 0.2% by mass or more and 15.0% by mass or less based on the mass of the fiber. Bundling fiber for. The sizing agent further contains one or more phosphorus-based surfactants selected from the group consisting of normal alkyl phosphate alkali metal salts and polyoxyethylene alkyl phosphate ester salts. Bundling fiber for the addition of the hydraulic set of. The bundled fiber for hydraulically-cured product addition according to claim 8, wherein the total amount of the sulfosuccinate salt and the phosphorus-based surfactant attached is 1.0% by mass or more based on the fiber mass of the bundled fiber. The mass ratio of the sulfosuccinate salt and the phosphorus-based surfactant is 10/90 or more and 90/10 or less, and the hydraulically cured product-added bundled fibers according to claim 8 or 9. The bundling fiber for adding a hydraulically cured product according to any one of claims 8 to 10, wherein the phosphorus-based surfactant is a normal alkyl phosphate alkali metal salt, and the alkyl group has 8 to 18 carbon atoms. The said focusing fiber is a polyolefin fiber, The shape of a fiber cross section is a multileaf shape, The focusing fiber for hydraulically hardening body addition of any one of Claims 1-11. A premix cement composition comprising cement and the bundled fiber for hydraulically hardening material addition according to any one of claims 1 to 12. A hydraulically set body, comprising cement and the bundled fiber for adding the hydraulically set body according to any one of claims 1 to 12. It is a manufacturing method of the bundled fiber for hydraulically hardening body addition of any one of Claims 1-12, Comprising:
A step of applying a treatment liquid of a sizing agent containing a sulfosuccinate salt to the tow bundled with a plurality of single fibers,
Bundling for adding a hydraulic cured product, which includes a step of drying the tow and adjusting the attached amount of the sizing agent to 1.0% by mass or more with respect to the mass of the fiber to bundle a plurality of single fibers. Fiber manufacturing method. The method for producing a bundled fiber for adding a hydraulically cured product according to claim 15, wherein the sulfosuccinate salt has a maximum tensile stress in a probe tack test of 100 gf/cm ² or more. The water according to claim 15 or 16, wherein the sulfosuccinate salt has a storage shear modulus of 0.04 MPa or more and 4.0 MPa or less and a loss tangent tan δ of 0.05 or more and 5.0 or less in dynamic viscoelasticity measurement. A method for producing a bundled fiber for adding a hardened body. The method for producing a focused fiber for adding a hydraulically cured product according to any one of claims 15 to 17, wherein the sulfosuccinate salt has a dynamic viscosity of 8 kPa·s or more in dynamic viscoelasticity measurement.