JP4998018B2 - Manufacturing method of fiber molded body - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a fiber molded body formed by bonding fibers with a binder resin, and more specifically, a fiber molding formed by mixing and impregnating a fiber sheet with a thermosetting resin as a binder and its curing agent. The present invention relates to a method for manufacturing a body .

  In recent years, since it is lightweight and has significant strength, etc., a fiber molded body in which fibers are bonded with a binder resin is used as an alternative member to conventional metal material molded products and plastic material molded products, such as automobiles, building materials, and electrical equipment. It is attracting attention in a wide range of fields. As the binder resin, a thermoplastic resin or a thermosetting resin is used. However, when a thermosetting resin is used, the thermosetting resin has been conventionally used because of easy impregnation and uniform impregnation of fibers. In many cases, the fiber was impregnated as a solution obtained by melting in a solvent or as a dispersion in which a thermosetting resin was dispersed in water. However, in this case, a drying process for removing the solvent component is necessary before press-molding the fiber body impregnated with the binder resin, which causes a problem of high cost.

  Therefore, there is Patent Document 1 as a method for manufacturing a fiber molded body that does not require a drying step while using a thermosetting resin as a binder. In the said patent document 1, the epoxy resin which is a thermosetting resin as a binder and this hardening | curing agent are impregnated to the fiber sheet, and it makes a prepreg, and the prepreg is hot-pressed and it is set as the fiber molded object. Specifically, a powdery thermosetting resin composition (hereinafter, the thermosetting resin composition is simply referred to as a composition) is obtained by applying mechanical energy to a mixture of an epoxy resin and a curing agent to react them. In addition, the fiber sheet is impregnated with the powdery composition.

JP 2000-280242 A

  By the way, since it is a depleted resource that cannot be reproduced because it is a fossil resource, and the negative impact on the environment after disposal becomes a problem, the need for a non-oil dependent society has increased in recent years. Therefore, the fiber molded body of Patent Document 1 using a petroleum-derived epoxy resin as a binder is not suitable for the social trend. In addition, the fiber sheet is impregnated with the powdered composition. However, simply adhering or applying the powder composition to the fiber sheet does not ensure adhesion to the fiber sheet. Heat treatment is required for adhering to the sheet, which increases the energy cost. And if it is a powder composition, it will be difficult to remove the composition once sprinkled etc. from a fiber sheet. In other words, for example, when the supply amount of the composition is uneven due to, for example, malfunction of the manufacturing apparatus, it is almost impossible to redo it.

Accordingly, an object of the present invention is to provide a method for producing a fiber molded body that can reduce the dependence on petroleum by using a plant-derived resin and can also reduce the energy cost.

  As a means for solving the above-mentioned problem, the method for producing a fiber molded body according to the present invention described in claim 1 comprises kneading a liquid curing agent into powdered phenolized lignin to obtain a clay-like phenolized lignin resin, The clay-like phenolated lignin resin applied as a binder to the fiber sheet is pressed. Here, “applying” the binder to the fiber sheet includes not only “impregnating” the binder with the fiber sheet but also simply “attaching” the fiber sheet. “Clay-like” means a state showing the same properties as general clay. That is, by kneading a liquid into a non-viscous powder, each powder develops a certain viscosity and becomes a single flexible lump, and the lump can hold a predetermined shape in a stationary state. It is also in a state equipped. The “fiber sheet” is a flat body made of fibers, and is a concept including a fiber mat having a relatively large thickness in the present invention as well as a sheet-like body having an extremely thin or thin thickness. The fiber sheet may be a non-woven sheet or a sheet woven with fibers. Moreover, a single layer sheet may be sufficient and the lamination sheet which laminated | stacked two or more sheets may be sufficient. In the present invention and the present specification, for the sake of convenience, among the phenolized lignins, the powdery one before kneading the liquid curing agent is directly used as “phenolized lignin” and the clay-like one kneading the liquid curing agent. “Phenolized lignin resin” is used separately.

  According to a second aspect of the present invention, in the method for producing a fiber molded body according to the first aspect, the clay-like phenolized lignin resin is impregnated into the fiber sheet by a non-heated press, and the prepreg It is formed into a predetermined shape by hot pressing. The “hot press” is a press in a heated state.

  According to a third aspect of the present invention, there is provided the method for producing a fiber molded body according to the second aspect, wherein the prepreg is formed by laminating the clay-like phenolized lignin resin into a sheet and laminating the fiber sheet. It is obtained by heat pressing. The lamination method at this time is not particularly limited. For example, one sheet-like phenolized lignin resin is laminated on one fiber sheet, or one sheet-like phenolized lignin resin is laminated on one fiber sheet from above and below. In some cases, a plurality of fiber sheets and sheet-like phenolized lignin are alternately laminated.

  According to a fourth aspect of the present invention, there is provided the method for producing a fiber molded body according to any one of the first to third aspects, wherein the clay-like phenolized lignin resin is separated from above and below by the two fiber sheets. It is sandwiched and pressed. The form of the clay-like phenolized lignin resin here is not particularly limited, for example, a sheet form or a dumpling form.

  Plant-derived raw materials have the advantage of being reproducible and friendly to the global environment because they are biomass resources. Therefore, according to the present invention in which phenolic lignin, which is a plant-derived thermosetting resin, is used as a binder, the dependence on petroleum can be reduced. In addition, since the phenolic lignin is made into a clay by kneading a liquid curing agent, it has good adhesion to the fiber sheet, so there is no need for heating when adhering or impregnating the fiber sheet, and no drying process is required. , Energy cost can be reduced. Moreover, since it has a shape-retaining property if it is in the form of clay, it can be applied to the fiber sheet after the binder is formed into a certain shape. Therefore, since the binder can be handled (gripped and moved), it is easy to select the amount to be applied to the fiber sheet and the application location, and if it is before pressing, the application location can be changed after the application once. Is possible. Thus, by making the binder clay, the degree of freedom of selection of various application forms according to the purpose and application is increased.

  If the prepreg is made by impregnating a fiber sheet with a binder before hot-pressing the fiber molded body into a predetermined shape, a bully and low-volume prepreg can be transported to various main molding factories. , Transportation costs can be reduced. For example, it is advantageous when the fiber used as the raw material of the fiber molded body is imported from overseas. In addition, if the prepreg is stored one step before it is stored in the final product state until shipment, it is advantageous for securing the storage location. Since the prepreg can be manufactured by a non-heating press, the energy cost is low.

  If the clay-like binder is formed into a sheet and laminated on the fiber sheet and then pressed, it can be impregnated uniformly. If a clay-like binder is sandwiched and pressed between two fiber sheets from above and below, it can be reliably impregnated without any waste.

  The fiber molded body of the present invention is obtained as a board member having a certain strength and the like by using a thermosetting resin as a binder, impregnating the fiber sheet with a curing agent mixed therein, and press-molding it into a predetermined shape. . As the binder, a powdery phenolized lignin obtained from a plant which is a lignocellulosic material is used, and a liquid one is used at room temperature (around 23 ° C.). When impregnating the fiber sheet with the binder, the powdery phenolized lignin is made into a clay by kneading a liquid curing agent (hereinafter, the clay-like phenolized lignin resin is also referred to as a clay-like binder). is there).

  The lignocellulosic substance is a substance mainly composed of cellulose or hemicellulose as a carbohydrate and lignin as a resin component, and typically corresponds to woody plants or herbaceous plants. The phenolized lignin obtained from this is a lignin in a state where the phenol derivative is chemically bonded to the molecular chain in the lignin and stabilized (grafted) when the lignin is isolated from the lignocellulosic substance in the presence of the phenol derivative. Lignin accounts for 20-30% of the wood, and is produced in tissues such as canal, temporary canal, and fiber as it grows in higher plants. It is known that this lignin can be used as a so-called biodegradable resin, and even if it is discarded, it is reduced in molecular weight by white rot fungi and further mineralized by being decomposed by bacteria such as Sphingomonas paucimobilis SYK-6. It has been. Therefore, phenolized lignin can be used as a resin friendly to the global environment. Phenolized lignin is typically obtained by subjecting a lignocellulosic material to concentrated sulfuric acid treatment in the presence of a phenol derivative to hydrolyze the lignocellulosic material, followed by steps such as washing and drying. Then, the obtained phenolized lignin is pulverized with various mills to obtain powder. In this case, the particle size of the phenolized lignin should be as fine as possible. When the particle size of the phenolized lignin is large, there are disadvantages such that even if a liquid curing agent is kneaded, it cannot be made into a good clay shape, and uniform impregnation becomes difficult. As a standard, the average particle size is about 1 to 50 μm, preferably about 1 to 30 μm.

  The phenolic lignin curing agent is not particularly limited as long as it is a liquid at room temperature capable of curing the phenolized lignin, and various types can be used. As the curing agent, for example, bisphenol A type epoxy resin, tetrabromobisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, tetramethylbiphenyl type epoxy resin, etc. Difunctional aromatic glycidyl ether, phenol novolac type epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene-phenol type epoxy resin, tetraphenylolethane type epoxy resin, etc., polyfunctional aromatic glycidyl ether, polyethylene glycol type epoxy resin , Polypropylene glycol type epoxy resin, neopentyl glycol type epoxy resin, dibromoneopentyl glycol type epoxy resin, hexanediol Multifunctional glycidyl ether such as epoxy resin, bifunctional alicyclic glycidyl ether such as hydrogenated bisphenol A epoxy resin, trimethylolpropane epoxy resin, sorbitol epoxy resin, glycerin epoxy resin Bifunctional aromatic glycidyl esters such as aliphatic glycidyl ether, diglycidyl phthalate, etc., bifunctional alicyclic glycidyl esters such as tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, dimer acid diglycidyl ester, Bifunctional aromatic glycidylamines such as N, N-diglycidylaniline, N, N-diglycidyltrifluoromethylaniline, N, N, N ′, N′-tetraglycidyl-4,4-diaminodiphenylmethane, 1, Polyfunctional aromatic glycidylamines such as bis (N, N-glycidylaminomethyl) cyclohexane, N, N, O-triglycidyl-p-aminophenol, alicyclic diepoxy acetals, alicyclic diepoxy adipates, ants Bifunctional alicyclic epoxy resins such as cyclic diepoxycarboxylate and vinylcyclohexene dioxide, bifunctional heterocyclic epoxy resins such as diglycidylhydantoin, polyfunctional heterocyclic epoxy resins such as triglycidyl isocyanurate, organopoly Examples thereof include bifunctional or polyfunctional silicon-containing epoxy resins such as siloxane type epoxy resins, dicarboxylic acid modified epoxy resins such as dimer acid modified epoxy resins, and trimethylol type epoxy resins. Among these, bisphenol A type epoxy resin, glycerin type epoxy resin, and trimethylolpropane type epoxy resin are preferable. One of these curing agents may be used alone, or two or more thereof may be mixed and used.

Moreover, a hardening accelerator (catalyst) can also be mixed as needed. The curing accelerator has effects such as accelerating the curing rate of the phenolized lignin and the curing agent and improving the crosslinking density. Examples of the curing agent include acid anhydrides, quaternary phosphonium salts, quaternary ammonium salts, imidazoles, DBU fatty acid salts, metal salts, and triphenylphosphine. Examples of acid anhydrides include dodecenyl succinic anhydride, polyazeline anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methyl nadic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetra Carboxylic acid, tetrabromophthalic anhydride, head acid anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic acid anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride Examples of the quaternary phosphonium salt system include tetrabutyl phosphonium diethyl phosphodithionate, tetraphenyl phosphonium bromide, and tetrabutyl phosphonium bromide. As tetraethylammonium bromide, tetrabutylammonium bromide and the like. Examples of imidazole compounds include 2-ethyl-4-methylimidazole, 2-phenylimidazole, 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole, 2,4-diamino-6- [2-methylimidazolyl- (1)] ethyl-s-triazine, 2-phenylimidazoline, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-heptadecylimidazole, etc. Examples of amine-based compounds include DBU (1,8-diaza-bicyclo- (5,4,0) -undecene-7) 2-ethylhexanoate, diethylenetriamine, triethylenetetramine, metaxylylenediamine, isophoronediamine. 1,3-bisami Methylcyclohexane, diaminodiphenylmethane, meta-phenylenediamine, diaminodiphenylsulfone, dicyandiamide, organic acid dihydrazide, benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol and the like, BF ₃ mono Lewis acid Examples include ethylamine and BF ₃ piperazine, and examples of the metal salt system include zinc octylate and tin octylate. Of these, amine-based and imidazole-based curing accelerators are preferable. These curing accelerators may be used alone or in a mixture of two or more, regardless of liquid or powder.

  Clay-like phenolized lignin resin is a mixture of powdered phenolized lignin and a liquid curing agent and a curing accelerator if necessary. Planetary mixer, Henschel mixer, Reika machine, planetary mixer, ball mill, medium It can be obtained by kneading with a stirring mill, a jet mill, an ang mill, a multistage mortar-type kneading extruder or the like. These kneaders are preferable in that they can be kneaded while applying a shearing force, but they may be hand-kneaded. Alternatively, it can also be obtained by diluting the phenolized lignin and the curing agent with a solvent such as acetone, methanol, tetrahydrofuran (THF), and distilling off only the solvent by vacuum concentration or the like.

  When kneading powdered phonolized lignin and a liquid curing agent with a kneader, the powdered phenolized lignin or between the powdered phenolized lignin and the kneading machine is ground by friction or shearing force, via a liquid curing agent. For example, heat of about 20 to 50 ° C. is generated due to fusion. The generated heat increases the kneading efficiency, and a good viscosity and the like can be expressed. Therefore, kneading is basically performed at normal temperature, but if the amount of heat generation is small, it may be heated slightly. When heating, the temperature of the raw material should not be 70 ° C. or higher. This is because when the temperature of the raw material exceeds 70 ° C., the reaction between the phenolized lignin and the curing agent proceeds. Therefore, the raw material temperature during kneading is preferably in the range of 30 to 60 ° C, more preferably 40 to 50 ° C, regardless of whether it is heated.

  The mixing amount of the liquid curing agent with respect to the powdered phenolized lignin can be adjusted as appropriate while combining the reaction equivalent (epoxy equivalent) with the powdered phenolized lignin, but it should be at least smaller than the weight of the powdered phenolized lignin. It is necessary that the clay-like binder has a suitable shape retaining property and viscosity. For example, if the mixing amount of the liquid curing agent is too large with respect to the powdered phenolized lignin, all of the curing agent does not react completely during hot pressing, and costs are wasted. The problem that it becomes easy to generate | occur | produce and a binder does not have shape retention property arises. On the other hand, if the amount of the liquid curing agent is too small relative to the powdered phenolized lignin, the phenolic lignin does not cure reliably, the binder does not become clay-like, and the strength of the fiber molded product decreases. Occurs.

  When knead | mixing powdery phenolized lignin, a liquid hardening | curing agent, etc., inorganic fibers, such as glass fiber and a carbon fiber, an inorganic filler, or a natural fiber can further be added and mixed as needed. Inorganic filler materials include silica, alumina, titanium oxide, beryllium oxide, magnesium oxide, calcium carbonate, titanium nitride, silicon nitride, boron nitride, titanium boride, tungsten boride, silicon carbide, titanium carbide, zirconium carbide, carbonized Examples include molybdenum, mica, clay, zinc oxide, carbon black, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, and antimony trioxide. Natural fibers are fibers that can be collected from trees and herbs. As woody species, coniferous trees such as cedar and cypress, broad-leaved trees such as shii, oak, cherry, and tropical trees can be used, and as herbs, bast plants that are easy to obtain good quality fibers are preferable, Examples include kenaf, ramie (flax), linen (flax), abaca (manila hemp), heneken (sisal hemp), jute (hemp), hemp (palm), palm, palm, mulberry, straw and bagasse. Further, mechanical pulp, chemical pulp, semi-chemical pulp, and various artificial cellulosic fibers synthesized from these pulps may be used.

  If these are added, the strength of the fiber molded body is improved, and the effect of reducing the voids of the fiber molded body due to air bubbles during the main molding can be obtained. Inorganic fibers and inorganic fillers mainly contribute to improvement in strength, impact resistance, and heat resistance, and natural fibers mainly contribute to reduction of voids in the fiber molded body. Further, various other additives can be added as necessary. Examples of these various additives include fillers, coupling agents, flame retardants, plasticizers, reactive diluents, pigments, and the like. By kneading these additive fibers and other additives into a clay-like binder, it is possible to simultaneously impregnate the fiber sheet with the binder and to apply the additives, thereby simplifying the production process. is there. Moreover, the trouble of storing the binder and the additive separately can be saved. In addition, when preparing a clay-like binder and storing it for a certain period of time without immediately using it, it is necessary to store it at a temperature of at least room temperature or less in order to suppress the reaction between the phenolized lignin and its curing agent. There is. Refrigerated storage is preferable, and frozen storage is more preferable.

  The clay-like binder thus obtained is impregnated into the fiber sheet. The fiber sheet is a fiber sheet made of natural fibers, and may be formed of the same natural fibers as those listed above. Among these, kenaf can be preferably used. Kenaf is an annual plant of the genus Hyacinth, which gives a remarkable growth potential that matures in only about five months, and tough long fibers that surpass wood fibers. Therefore, the use of kenaf can protect forest resources that take many years to become mature trees. In addition, with its vigorous growth potential, it absorbs and decomposes a large amount of carbon dioxide in the air in a short period of time and fixes it as carbon, which has the advantage of contributing to the improvement of the global environment such as global warming. Even if the fiberboard is burned as waste material, the carbon dioxide originally taken from the air only returns to the atmosphere, so the amount of carbon dioxide in the atmosphere does not increase. Compared to the use of petroleum-derived resources in which carbon dioxide is unilaterally stored, there is an advantage that is friendly to the global environment.

  What is necessary is just to manufacture a fiber sheet by a known method. For example, kenaf fibers obtained by biodegradation (letting), steaming, blasting, etc. are first defibrated using a card machine or an air array machine. Next, a web may be formed with the obtained defibrated fibers and formed into a sheet shape with a needle punch or a fleece. Alternatively, a kenaf fiber can be woven into a sheet shape. If it is a non-woven sheet, the fiber direction may be oriented as necessary, or may be laminated. If the thickness at this time is large, the fiber mat is actually exhibited. The size and shape of the fiber sheet are not particularly limited, and may be set as appropriate from the viewpoint of the purpose of using the fiber molded body and the transportability of the prepreg described later.

  Next, a method for impregnating a fiber sheet with a clay-like phenolized lignin resin including a curing accelerator as required, that is, a method for producing a prepreg will be described. The impregnation of the clay-like binder into the fiber sheet is performed by placing or laminating and pressing a clay-like binder formed in a predetermined shape on the surface of the fiber sheet. Specifically, as shown in FIG. 1, a clay-like binder 10 is formed into a sheet shape and sandwiched between two fiber sheets 20 and 20 from above and below to form a laminated body. By pressing at a normal temperature in a heated state (cold press), a prepreg in which a fiber sheet is impregnated with a binder can be obtained. Since the clay-like binder also has a certain fluidity, the clay-like binder 10 penetrates into the upper and lower fiber sheets 20 and 20 by pressing the laminate. Further, since the clay-like binder has a certain viscosity, it has a significant adhesion, and even when pressed in a non-heated state, the binder and the fiber sheet can be favorably adhered. In other words, heating energy is not required when forming a prepreg. Furthermore, uniform impregnation is possible if it is in sheet form.

  The sheet-like binder can be obtained by pressing a clay-like binder and extending it thinly. At that time, it is possible to prevent the binder from sticking to the press machine by disposing a fluororesin sheet having high peelability such as tetrahydrofuran on the press machine surface or applying a release agent. The thickness at the time of making the clay-like binder into a sheet is not particularly limited, and may be appropriately set depending on the thickness of the fiber sheet 20 or the required amount of the binder according to the purpose of use of the fiber molded body. . Further, the size and shape of the clay-like binder in the form of a sheet are not particularly limited, but it is preferable that the size is about one smaller than the fiber sheet 20. If the sheet-like binder 10 is set to the same size as the fiber sheet 20, the clay-like binder 10 may leak out to the outside of the fiber sheet 20 when pressed to form a prepreg. It is also possible to stack a plurality of relatively small sheet-like binders 10 side by side.

  Alternatively, as shown in FIG. 2, the clay-like binder 10 can be placed in a dumpling shape and placed on the fiber sheet 20. There are no particular restrictions on the size, number of places, and place of placement at that time, but it is preferable to place the fiber sheets 20 adjacent to each other at equal intervals so that the fiber sheets 20 can be entirely impregnated. However, if only a part of the fiber sheet 20 is to be impregnated with the binder, the fiber sheet 20 may be placed only in a corresponding place.

  Further, as shown in FIG. 1 and FIG. 2, the clay-like binder 10 may not only be sandwiched between the two fiber sheets 20, 20 but may be simply placed or stacked on the single fiber sheet 20. In this case, it is preferable that a release sheet or a release agent is also provided on the surface of the press machine when the prepreg is formed. Furthermore, the peelability of the clay-like binder 10 can be improved by cooling the press with a refrigerant or the like.

  Then, when the prepreg obtained as described above is hot-pressed (main molding) with a press machine in which one or a plurality of prepregs are laminated and formed into a predetermined shape, the phenolized lignin impregnated in the fiber sheet and By reacting with the curing agent and curing, a board-like fiber molded body formed in a predetermined shape can be obtained. FIG. 3 shows this series of manufacturing flow. The temperature during the main molding is at least 160 ° C., which is a temperature at which the phenolized lignin can react with the curing agent, and is preferably 180 ° C. or more. Further, in order to avoid carbonization of fibers due to the heat of the hot press and useless energy costs, the main molding temperature is preferably 220 ° C. or less, and more preferably 200 ° C. or less.

  The ratio of the fiber and the binder is within a range that can be used as a board member having at least a certain strength, and the amount of the binder (resin ratio) in the fiber molded body is 10 to 99% by weight. What is necessary is just to set suitably according to the purpose of use. However, when the resin ratio is 30% by weight or less, the specific gravity of the obtained fiber molded body is decreased, and voids due to hot pressing tend to increase remarkably. The resin ratio in the fiber molded body is preferably 30 to 80% by weight, more preferably 50 to 70% by weight, and still more preferably 55 to 65% by weight.

(Example)
Dry phenolized lignin powder (average particle size 5 to 10 μm) isolated from kenaf by concentrated sulfuric acid treatment, and trimethylolpropane type epoxy curing agent (trade name: Denacol EX-321 manufactured by Nagase ChemteX Corporation) which is liquid at room temperature Is mixed at a ratio of 2: 1, and a small amount of DBU fatty acid salt catalyst (trade name: U-CAT5002 manufactured by San Apro Co., Ltd.) is added as a curing accelerator (1% by weight with respect to the total amount of the binder). A kneading machine (Miyazaki Tekko Co., Ltd., trade name: FM-P) kneaded at a rotational speed of 60 rpm while maintaining the raw material temperature at about 40 to 60 ° C. to prepare a clay-like binder. About 6 g of the obtained clay-like binder was cold-pressed to obtain an elliptical sheet-like binder having a size one size smaller than the fiber sheet. This was laminated so as to be sandwiched from above and below by a kenaf fiber sheet having a length of 120 mm, a width of 120 mm, and a basis weight of 900 g / m ² , and the laminate was cold pressed to obtain a prepreg having a resin rate of 60% by weight. Then, one prepreg was hot pressed at a temperature of 180 ° C. and a pressure of 20 kg / cm ² for 3 minutes to obtain a flat fiber board having a thickness of 1.8 mm.

  The bending strength, flexural modulus, and Izod impact of the fiber board thus obtained were measured, and compared with a comparative example of a solvent-based kenaf fiber board in which phenolic lignin was melted and impregnated with acetone. The performance was confirmed. The results are shown in FIGS. In addition, the external dimensions, thickness, resin ratio, and the like of the comparative example used at this time are the same as those in the above example.

The measurement method for each data is as follows.
Bending strength: measured based on JIS R1663 Flexural modulus: measured based on JIS K6911 Izod impact: measured based on JIS K7062

  From the results of FIGS. 4 and 5, the bending strength and the bending elastic modulus of the example and the comparative example were equivalent. Further, from the results shown in FIG. 6, the Izod impact strength of the example was higher than that of the comparative example. From the above results, it was confirmed that even when the binder was impregnated in the form of clay, the binder could be uniformly impregnated similarly to the conventional solvent impregnation, and an inferior performance could be obtained.

It is a perspective view which shows one form which provides a binder to a fiber sheet. It is a perspective view which shows the other form which provides a binder to a fiber sheet. It is a flowchart which shows a manufacturing process. It is a graph which shows a bending strength test result. It is a graph which shows a bending elastic modulus test result. It is a graph which shows an Izod impact test result.

Explanation of symbols

10 Clay-like phenolized lignin resin 20 Fiber sheet

Claims (4)

  A method for producing a fiber molded body, in which a liquid curing agent is kneaded into powdery phenolized lignin to form a clay-like phenolized lignin resin, and the fiber-like sheet is pressed with the clay-like phenolated lignin resin as a binder.   The method for producing a fiber molded body according to claim 1, wherein the clay-like phenolized lignin resin is used as a prepreg in which the fiber sheet is impregnated by a non-heated press, and the prepreg is finally formed into a predetermined shape by a hot press.   The said prepreg is a manufacturing method of the fiber molded object of Claim 2 obtained by non-heat-pressing, after making the said clay-like phenol-ized lignin resin into a sheet form, laminating | stacking on the said fiber sheet. The method for producing a fiber molded body according to any one of claims 1 to 3, wherein the clay-like phenolized lignin resin is sandwiched and pressed between the two fiber sheets from above and below .

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