JP2005179840A - Method for washing fiber structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for washing a fiber structure by which the fiber structure in which the residual amount of an oil solution attached to the fiber surface is adequately controlled can be obtained. <P>SOLUTION: The method for washing the fiber structure comprises carrying out washing treatment of a fiber structure to which an oil solution is attached with a washing solution containing a nonionic surfactant in 1:5 to 1:50 bath ratio for 20-120 min at 60-100°C so as to keep the residual oil solution of the fiber surface in an amount of 0.01-2 mass% based on the fiber structure. When the treated fiber structure is used as a reinforcing fiber substrate for a fiber-reinforced resin, a fiber structure excellent in a resin-impregnating property and capable of optimizing processability in resin finishing can be obtained. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for cleaning a fiber structure, and more particularly to a method for cleaning a fiber structure used for a fiber reinforced resin product or the like.

  As a reinforcing fiber used for a composite material such as a fiber reinforced resin, an aramid fiber is generally used. In the process of producing these fibers, a spinning oil is used in the spinning process in order to impart necessary characteristics, so that the oil adheres to the fiber surface before washing.

  In the case where the fiber to which such an oil agent is attached is used as the reinforcing fiber base material of the fiber reinforced resin, the final finished product is not subjected to an appropriate treatment on the fiber in the step of impregnating the fiber base material with a resin such as a phenol resin. There was a problem that it was not what was intended.

Therefore, a scouring step for removing the spinning oil is performed before the resin impregnation treatment. Conventionally, in the scouring step, it has been considered that the oil agent should be removed as much as possible and there should be no residue (residual oil agent) on the fiber surface. However, when the fiber from which the residual oil agent is completely removed is used as the reinforcing fiber of the fiber reinforced resin, there is a drawback that a defect occurs in the resin permeability in the resin impregnation step.
In addition, as a well-known document relevant to this invention, there exist the following.
JP 2001-295913 A

  The present invention has been made in view of the above circumstances, and when used as a reinforcing fiber base material for a fiber reinforced resin, a fiber structure that is excellent in resin permeability and can optimize workability during resin processing. It aims at providing the washing | cleaning method of the fiber structure which can be obtained.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors have made it possible to appropriately retain the oil on the fiber surface rather than removing all the oil used in the spinning and spinning stages. As a result of finding out that it is preferable to use as a reinforced fiber base material for resin and further examining various chemicals (cleaning solutions) and cleaning methods, the amount of residual oil on the fiber surface is 0.01-2. In the case of mass%, when this is used as a reinforced fiber base material for fiber reinforced resin, it has been found that the permeability of the resin to the fiber base material is improved and the workability at the time of resin processing can be optimized. It came to.

  Accordingly, the present invention provides the oil-attached fiber structure and the cleaning solution containing the nonionic surfactant at a bath ratio of 1: 5 to 1:50 at 60 to 100 ° C. for 20 to 120 minutes. Is provided, and the amount of the residual oil on the fiber surface is set to 0.01 to 2% by mass with respect to the fiber structure.

  According to the cleaning method of the present invention, it is possible to obtain a fiber structure in which the remaining amount of the oil attached to the fiber surface is appropriately adjusted, and when this is used as a reinforcing fiber base material for fiber reinforced resin, It is possible to obtain a fiber structure that is excellent in properties and can optimize processability during resin processing.

Hereinafter, the present invention will be described in more detail.
In the cleaning method of the present invention, the oil-attached fiber structure and the cleaning solution containing a nonionic surfactant are used at a bath ratio of 1: 5 to 1:50 at 60 to 100 ° C. for 20 to 120 minutes. A thing is wash-processed and the amount of residual oil agents on the fiber surface shall be 0.01-2 mass% with respect to a fiber structure.

  Here, the fiber structure used in the present invention is not particularly limited, and examples thereof include yarn, woven fabric, knitted fabric, non-woven fabric (felt, etc.), cut fiber, and the like. Examples of the structure of the fiber structure include, for example, a plain weave, a twill weave, a satin weave, and the like as a woven structure, and a flat knitting, a circular knitting, and the like as a knitting structure. Further, the shape of the woven fabric, the knitted fabric, the nonwoven fabric or the like is not particularly limited, but examples thereof include a cylindrical shape and a sheet shape. The fibers used in these fiber structures are not particularly limited. For example, meta-aramid fibers, para-aramid fibers, polyamide fibers such as nylon, polyester fibers, carbon fibers, glass fibers, polypropylene fibers, polyethylene fibers, rayon, etc. Natural fibers such as synthetic fibers, chemical fibers, cotton, silk, and wool. These fibers can be used alone or in combination of two or more. In the present invention, among these, polyester fiber, aramid fiber, carbon fiber, polyamide fiber (nylon, etc.), cotton and the like can be preferably used, and in particular, aramid fiber, especially para-type aramid fiber is 0 to 100% by mass. And those containing 100 to 0% by mass of meta-type aramid fibers, more preferably those containing 40 to 50% by mass of para-type aramid fibers and 60 to 50% by mass of meta-type aramid fibers have high heat resistance and high strength. From this point, it can be preferably used.

  The oil agent adhering to the fiber structure is an oil agent used in a fiber spinning process, a spinning process, or a spinning spinning process, or a machine oil used in a weaving and knitting process, as a component of these oil agents. For example, mineral oil, ester-based smoothing agent, ether-based smoothing agent such as polyethylene oxide-polypropylene oxide copolymer, silicone oil, various waxes, nonionic, anionic and cationic surfactants, emulsification Stabilizers, antistatic agents, bundling agents and the like can be mentioned.

  Specifically, mineral oils include naphthenic and paraffinic mineral oils and mixtures thereof, and ester-based smoothing agents include esters of higher alcohols and fatty acids, diisooctyl phthalate, diisooctyl adipate, diisopropylene. Esters of adipic acid such as octyl azelate, polybasic acids such as azelaic acid, phthalic acid, trimellitic acid and higher alcohols, polyhydric alcohols such as ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, neopentyl glycol Examples of silicone oils such as esters of higher fatty acids, aromatic carboxylic acid esters and higher fatty acid esters include amino-modified silicone oils. The total amount of oil agent attached to the oil agent-attached fiber structure used in the present invention is usually 0.1 to 5.0% by mass, particularly 0.2 to 1.0% by mass, based on the fiber structure.

  In the present invention, a nonionic surfactant is used as the surfactant used for cleaning the oil-attached fiber structure. Examples of the nonionic surfactant used in the present invention include polyoxyalkylene alkyl ether, polyoxyalkylene alkyl phenyl ether, polyoxyalkylene allyl ether, polyoxyalkylene glycol, polyoxyalkylene alkylamine and the like. . In addition, examples of the polyoxyalkylene group include a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group, etc. The number of moles added of these groups is preferably 6 to 50, more preferably 30 to 40. is there. In the present invention, it is preferable to use polyoxyethylene alkyl ether as a main component from the viewpoint of detergency and resin permeability, and those having a polyoxyethylene addition mole number of 6-50, especially 30-40. It can be used suitably.

  In the present invention, from the point of removal or dispersion of fiber deposits (adhesive oil), 0.5 to 30 o. w. Preferably used at a concentration of f%, 1-5o. w. It is more preferable to use f%. If the amount of the nonionic surfactant used is too small, deposits (residual oil agent) remain too much, and if it is too much, most of it may be removed.

  In the present invention, a surfactant other than the above may be used in combination as long as the effects of the present invention are not impaired, and anionic surfactants, cationic surfactants, amphoteric surfactants, etc. are all commercially available products. Can be used. Examples of the anionic surfactant include fatty acid soaps that are saturated or unsaturated fatty acid salts such as lauric acid, myristic acid, palmitic acid, stearic acid, and oleic acid, alkyl sulfate esters, alkyl sulfates, and alkylbenzene sulfates. , Polyoxyalkylene alkyl ether sulfate ester salt, polyoxyalkylene alkyl ether phosphate ester salt, sulfosuccinate and the like. Examples of the salt include sodium salt, potassium salt, ammonium salt, alkanolamine salt and the like. Moreover, as an alkyl group, a C10-C20 thing is preferable and a C16-C18 thing is more preferable. Examples of the polyoxyalkylene group include a polyoxyethylene group and a polyoxypropylene group.

  Examples of the cationic surfactant include alkyltrimethylammonium salts and dialkyldimethylammonium salts, and those having an alkyl group having 8 to 20 carbon atoms, particularly 12 to 17 carbon atoms are preferable. Examples of the salt include chloride salts and bromide salts.

Examples of amphoteric surfactants include alkyl betaines and alkylamidopropyl betaines.
These surfactants can be used individually by 1 type or in mixture of 2 or more types. Moreover, water etc. can be used as a solvent of the said washing | cleaning solution.

  In the above-mentioned cleaning solution, alkali builder such as sodium hydroxide, sodium carbonate, sodium phosphate, etc. used in ordinary scouring process, ethylenediaminetetraacetate, diethylenetriaminepentaacetate, as long as the object of the present invention is not impaired It is optional to contain a chelating agent such as a polycarboxylate.

  In the cleaning method of the present invention, the oil agent-adhered fiber structure is cleaned with a cleaning solution containing a nonionic surfactant, and the residual oil agent adhering to the fiber surface is within the above range. In this case, the cleaning method is not particularly limited, and can be performed by a known method, and examples thereof include a dipping method and a padding method.

Here, the processing conditions of the cleaning method of the present invention are such that the bath ratio is 1: 5 to 1:50, more preferably 1:10, the processing temperature is 60 to 100 ° C., and the processing time is 20 to 120 minutes. In particular, a treatment temperature of 100 ° C. and a treatment time of 40 to 60 minutes are preferable, and the number of washings is preferably 1 to 5 times. If the cleaning treatment conditions are below, too much fiber deposit (residual oil) remains, and if it exceeds, the fiber deposit (residual oil) is almost removed.
Moreover, after washing | cleaning, it can wash with water, spin-dry | dehydrate, and dry by a conventional method.

  According to the cleaning method of the present invention, it is possible to obtain a fiber structure in which the residual adhesion amount of the oil agent adhered to the fiber surface is adjusted to 0.01 to 2% by mass, particularly 0.1 to 1.5% by mass. Is. Here, as the residual oil agent, the same oil agents as those containing the above-mentioned components can be exemplified, but in particular, one or two or more kinds selected from waxes, anionic surfactants, and nonionic surfactants are included. It is preferable that the oil agent remains and adheres. In this case, even if the residual oil agent adhesion amount of the fiber structure after washing is too small or too large, the permeability of the resin when used as a reinforcing fiber substrate of the fiber reinforced resin is deteriorated.

  Moreover, the moisture content of the fiber structure after washing is preferably 0.01 to 1.0% by mass, more preferably 0.05 to 0.2% by mass from the viewpoint of resin permeability. In addition, the measuring method of the oil agent adhesion amount of a fiber structure and a moisture content is as mentioning later.

  Since the fiber structure obtained by the cleaning method of the present invention has a surface residual oil amount adjusted to the above range, particularly when used as a reinforcing fiber base material for fiber reinforced resin, Resin permeability can be improved.

  Here, the resin used for the fiber reinforced resin is not particularly limited, and examples thereof include a phenol resin, an epoxy resin, a polyester resin, a polyimide resin, and a CP resin (crosslinked polyesteramide, crosslinked polyaminoamide). These resins can be used by impregnating the reinforcing fiber base material, or can be used by placing the base material in the mold and then injecting the liquid resin into the mold to impregnate the base material, or The base material may be impregnated and dried in advance and used as a semi-cured state, and can be appropriately selected depending on the type of the fiber base material, the shape of the target molded product, the molding method thereof, and the like.

  As a method for molding the fiber reinforced resin, known methods such as injection molding, compression molding, injection molding, and extrusion molding can be employed. The fiber structure obtained by the cleaning method of the present invention can be suitably used especially for molding a fiber reinforced resin molded body by injection molding, compression molding or the like. Specifically, a resin gear, a resin bearing It can use suitably for manufacturing molded objects, such as.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following examples. In the following examples,% indicates mass%.

[Example 1]
A 20/1 aramid fiber (trade name: Cornex, manufactured by Teijin Ltd.) was knitted into a cylinder of 8 cm in diameter and placed in a protective bag, and filled into an overmeier dyeing machine. As a cleaning solution, male spin 40D (polyoxyethylene alkyl ether, manufactured by Tokai Oil Co., Ltd.) 3o. w. Used as an aqueous solution of f%, the temperature was raised from a water temperature (25 ° C.) to 100 ° C. in 30 minutes at a bath ratio of 1:10, and the cleaning liquid was circulated at 100 ° C. for 60 minutes. Thereafter, the liquid was drained and washed once with water. Subsequently, it was dehydrated with a centrifugal dehydrator for 30 minutes and dried with a low-temperature high-frequency dryer for 2 hours. The moisture content and residual oil adhesion amount of the obtained tubular knitted fabric were measured by the following methods, and found to be 0.93% and 0.095% (components: wax, anionic and nonionic surfactant), respectively. It was.

<Method of measuring moisture content>
The moisture content of the tubular knitted fabric was calculated by the following equation by measuring the mass change before and after drying the sample.
Moisture content (%) = [mass before washing (g) −mass after drying (g)] / mass after drying (g)
× 100
<Measurement method of oil adhesion amount>
Using a set of rapid residual oil extraction devices (R-II type, manufactured by Tokai Keiki Co., Ltd.), a sample obtained by loosening a tubular knitted fabric into a yarn shape was measured according to the following operation using cyclohexane as a solvent.
(1) Weigh 2 g of sample and tray in a natural state.
(2) Place the tray between the two rings, loosen the sample, and lightly pack the tube between the samples.
(3) Add 10 ml of solvent and drop about 5 ml.
(4) When the dropped solvent evaporates, press the remaining solvent with a push rod 3 to 6 times, and drop the solvent onto the tray.
(5) When the solvent evaporates, add 5 ml of the solvent and push it with a push rod as described above.
(6) When the solvent evaporates, take out the tray, let it cool, and weigh it.
The oil agent adhesion amount was calculated from the following formula.
Oil amount (%) = (w′−w) / [W− (w′−w)]
w: Mass before extraction of tray (g)
w ′: mass after extraction of the tray (g)
W: Mass of sample (g)

  When this tubular knitted fabric was used as a reinforcing fiber base material and injection molding was performed to form a fiber reinforced resin molded body (resin gear), good results were obtained in the affinity of the resin during resin injection.

Claims (5)

  The oil-attached fiber structure and the cleaning solution containing the nonionic surfactant are washed at a bath ratio of 1: 5 to 1:50 at 60 to 100 ° C. for 20 to 120 minutes, and the fiber-attached fiber structure is washed. A method for cleaning a fiber structure, characterized in that the amount of residual oil on the surface is 0.01 to 2% by mass relative to the fiber structure.   2. The method for cleaning a fiber structure according to claim 1, wherein the nonionic surfactant is polyoxyethylene alkyl ether.   The fiber structure according to claim 1 or 2, wherein the fiber structure contains one or more selected from polyester fiber, aramid fiber, carbon fiber, polyamide fiber, and cotton fiber. How to wash things.   4. The fiber structure cleaning product according to claim 1, 2 or 3, wherein the residual oil agent is an oil agent containing one or more selected from wax, anionic surfactant and nonionic surfactant. Method.   The method for cleaning a fiber structure according to any one of claims 1 to 4, wherein the fiber structure is for a fiber reinforced resin gear or a fiber reinforced resin bearing.