JP3695980B2 - Paper liquefaction method, paper liquefaction composition, and method for producing molded article - Google Patents

Description

【００５４】
（比較例１）
使用済のＯＡ紙（Ａ４）をシュレッダーにより、幅５mmの帯状に裁断した。さらに、はさみを用いて短く切断した。こうして裁断された紙は、最長辺の長さが５mm以下のものは１％未満であった。
【００５５】
得られた紙１００部に対して、ポリエチレングリコール（平均分子量約４００）１４０部、グリセリン６０部、硫酸６部を加えて、ニーダー（ダルトン社製、ＫＭ−５型）に投入し、１５０℃において１時間攪拌した。攪拌中、特に裁断紙を投入した攪拌開始初期において、絡み合った紙が攪拌子と容器の間に挟まれることにより機械が異常音を発生して作動停止することが数回発生し、その度に絡み合った紙を解いて操作を続行した。
【００５６】
１時間後、得られた混合物は液状であったが、紙の断片が多数残っているのが目視で観察され、液化は不十分であった。
【００５７】
（比較例２）
使用済のＯＡ紙（Ａ４）をシュレッダーにより、幅５mmの帯状に裁断した。さらに、はさみを用いて短く切断した。こうして裁断された紙は、最長辺の長さが５mm以下のものは１％未満であった。
【００５８】
紙の液化装置として、万能混合攪拌機の代わりに１７０℃に調温された口径２０mmの卓上押出機（原田製作所社製）を用いて、比較例１と同様に液化を試みた。ところが、原料紙が押し出し機中に入り難く、大部分が投入口に残り、液化操作が進行しなかった。押出機のスクリュー回転数を１３rpmの低速から３０rpm まで変えてみても結果は同じであった。
【００５９】
（実施例９）
実施例５で得られた液化物１００重量部に、イミダゾール４重量部及び整泡剤（ＳＺ−１６２７、日本ユニカー製）２重量部を添加し、２０秒間高速攪拌した。この混合物に、イソシアネート（ＭＤＩ−１００、日本ポリウレタン工業（株）製）７５重量部を加えて１０秒間高速攪拌し、あらかじめ用意しておいた型に注入して成形体を作製した。この方法によって、室内照明の枠、緩衝材、自動車内装用のクッション材等を作製することができた。
【００６０】
（実施例１０）
新聞紙、雑誌及びシュレッダーで裁断されたＯＡ紙が混合された古紙を鉄製のタンクに投入し、水を加えてゆっくりと一晩攪拌した。液状になった紙をタンクから吸い上げて水を切り、さらに乾燥器を用いて十分に乾燥した。得られた紙を、穴の直径が１mmのふるいを取り付けたカッター式破砕機（森田精機工業社製、ＪＣ―５型）によりさらに裁断した。こうして裁断された紙は、繊維同士が絡まり難い流動性のある粉末状繊維であった。顕微鏡で観察すると、繊維長が１mmを超えた紙繊維の含有量は、７．４％であった。
【００６１】
こうして得られた裁断紙１００部と共に、フェノール１００重量部及び硫酸３重量部を万能混合攪拌機（ダルトン社製、ＤＭＶ型）に投入し、この混合物を１５０℃において１時間攪拌した。得られた液化物の未液化残渣率を実施例の測定方法によって測定したところ、未液化残渣率は８．２％であり、液化物は室温で固体であった。
【００６２】
得られた固形物１００重量部に、平均粒径１０μｍのシリカ（商品名ＮＡ１、龍森社製）１００重量部、長さ１mmのガラス繊維のチップストランド５０重量部（日本板硝子社製）、カルナバワックス２重量部、水酸化カルシウム６重量部及び硬化剤としてヘキサメチルテトラミン２５重量部を加えて、ヘンシェルミキサーを用いて２分間混合した。さらに、２本ロールを用いて１２０℃で１分間溶融混練した。得られた溶融混合物を室温で固化し粉砕した後に、プレスにより１０φ×１０mmのタブレットに成形した。
【００６３】
こうして得られたタブレット状の成形材料を圧縮成形することによって、プリント基板用の基板、パソコンの筐体、携帯電話の筐体などの各種成形品を作製することができた。成形品の外観は良好で、実用上の要件を満たすものであった。
【００６４】
【発明の効果】
以上の記載から明らかなように、本発明よれば、使用済の古紙から効率よく低コストで紙液化物を調製することができ、これを用いて使用価値の高い各種のプラスチック成形体を作ることが実用化可能となる。従って、古紙のリサイクル用途の開発及び化石資源の使用量の低減を進めることができ、資源の保全及び有効利用の観点からその価値は極めて大きい。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper liquefaction method, a paper liquefaction composition, and a method for producing a molded body using the same, for efficiently producing a chemical product such as a plastic molded body from waste paper.
[0002]
[Prior art]
Mankind has created various products using resources on the earth to improve and enrich their lives. For example, paper used as a recording medium for newspapers, magazines, OA, etc. is produced from wood resources, and plastic and other chemical products are produced from fossil raw materials such as petroleum, which are consumed for producing chemical products. The amount of fossil raw material to be produced has reached an enormous amount at present. However, since the amount of resources that seem to be abundant is actually limited, from the viewpoint of environmental conservation and effective use of resources, reduction of resource usage and resource reuse are strongly desired. Development of resource recycling technology is underway.
[0003]
However, the recycling of chemical products as fossil resources has various problems that cannot be easily overcome technically and economically, so that the chemical products are not collected and regenerated so much. In particular, since the range of chemical products that can be recycled is limited, it is difficult to reduce the amount of fossil resources that are required as raw materials for production even if the recovery and recycling of chemical products is ongoing. Are not considered to progress sufficiently.
[0004]
On the other hand, with regard to wood resources, technologies for recycling used paper have been established, and collection of used paper such as OA paper, newspaper, and magazines has been promoted in order to expand recycling as recycled paper. However, due to the cost and other problems associated with the deinking process that occurs when paper is recycled, the used paper that is effectively used for paper recycling is limited to a portion of the total recovered recovered paper, and a large amount of excess recovered Waste paper is generated. If this situation continues, the recovery of waste paper will be suppressed, which will be a major obstacle to the effective use of wood resources.
[0005]
[Problems to be solved by the invention]
Under these circumstances, in order to promote effective use of resources, we will develop technologies that enable the use of resources for new recycling applications that promote the recycling of resources, in particular, develop cross-resource recycling technologies and activate recycling. It is necessary to make it.
[0006]
In order to solve the above problem, the present invention provides a resource cross-recycling technology that enables sufficient recycling of paper by activating recycling by using surplus recovered waste paper for new recycling applications. This is the issue.
[0007]
Another object of the present invention is to provide a cross-resource recycling technology that can convert raw materials other than chemical products into plastic raw materials in order to reduce the amount of fossil resources used.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present inventors have conducted intensive research and found that it is possible to efficiently liquefy waste paper and produce a high-quality chemical product using the obtained paper liquefaction product. .
[0009]
The paper liquefaction method of the present invention heats a mixture of at least one liquid compound selected from the group consisting of a hydroxyphenyl compound, a polyhydric alcohol compound, and a cyclic ester compound, an alkali catalyst or an acid catalyst, and paper. This is a method for liquefying paper, and includes a step of defibrating the paper to be liquefied in advance.
[0010]
The defibrated paper has a bulk density of 200 g / L or less, a fiber length of 0.2 mm to 2 mm in fibers of 50% or more of the paper, and the defibrated paper is previously wetted in the mixture A step of causing
[0011]
Pulp sludge is used as the liquefied paper, and the fiber having a fiber length of 0.2 to 2 mm in the defibrated paper is 50% or more.
[0013]
Furthermore, the gist of the method for producing a molded body of the present invention is to add a curing agent for isocyanate or phenol resin to the liquefied paper liquefied by the above-described paper liquefaction method, and to perform curing and molding.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Paper is manufactured using pulp composed of cellulosic fibers of wood and other plants, and is mainly composed of lignocellulose (a general term for cellulose, hemicellulose, and lignin). As for lignocellulose of wood, a method for preparing a resin by liquefying this is known. For example, JP-A 61-261358, JP-A 62-79230, JP-A 8-225653, etc. It is disclosed. Therefore, it is considered that a lignocellulose liquefied product can be prepared and a chemical product can be produced using the lignocellulose liquefied product by liquefying the lignocellulose of paper using such a liquefaction technique.
[0015]
However, when the paper is liquefied by the above liquefaction method, the following points are problematic.
[0016]
First, the above-described liquefaction method requires a long time to liquefy a small amount of woody lignocellulose at an experimental level, and cannot cope with the above processing at an industrial production level. Furthermore, since the method is aimed at liquefaction of wood, it is not adapted to liquefaction of paper having a composition and a structure different from those of wood.
[0017]
Secondly, since paper is an aggregate of fibers and has a structure that easily retains air, contact with a highly viscous liquefying agent is likely to be hindered by air. Substances for adding various functions other than lignocellulose have been added, and the progress of the liquefaction reaction tends to be hindered due to contact inhibition by these substances. Moreover, the fact that the fibers are closely entangled with each other and the density is relatively high is also the cause of the low liquefaction rate per unit weight of paper and the long time required for liquefaction.
[0018]
Therefore, in order to put paper liquefaction into practical use as a recycling technology, it is important that paper can be liquefied efficiently in large quantities on an industrial production scale. For this reason, in the present invention, in order to facilitate the contact with the liquefying agent and improve the liquefaction rate per unit weight, the air held between the paper fibers by unraveling the liquefied paper fibers is used for liquefaction. It is easily dissociated at the time of contact with the drug, and liquefies by ensuring contact between the paper and the liquefying drug containing the catalyst. By defibrating the paper, the liquefaction of the paper fibers in the drug progresses as a whole, and the unliquefied fibers that are being liquefied easily disperse and the size of the undecomposed residue is reduced. Further, contact inhibition with a drug due to a coating agent or the like on the paper surface can be greatly reduced. Since paper is closely entangled with fibers, liquefaction hardly progresses to the center of the cut piece even when cut finely, and a granular fiber lump tends to remain as an unliquefied residue. No lump remains, and the unliquefied residue becomes fine fibers. Therefore, the liquefied material obtained becomes more homogeneous, and the appearance and quality of the molded product produced using the liquefied material are also improved. Further, the non-liquefied residue remaining in a fibrous form may exhibit a specific function such as a reinforcing material in the manufactured molded body. Therefore, in the present invention, taking into account the physical properties of the molded article to be manufactured, controlling the liquefaction rate of the paper and adjusting the state of the liquefied product, it is possible to obtain a chemical product of a quality that could not be obtained with the conventional paper liquefied product. It is done.
[0019]
The starting material used for producing the lignocellulose liquefied product may be any paper, and examples thereof include OA paper, newspaper, magazine, cardboard, wrapping paper, thermal paper, and pulps. Pulp sludge generated in the paper production process or shearing process cannot be used for paper production because of its short fiber length and is discarded, but such a thing can also be suitably used as a raw material. In addition, according to the present invention, it is possible to effectively use cut old paper that has been cut and discarded because it cannot be used for paper recycling because of the necessity for information management.
[0020]
The raw paper is defibrated so that there are many gaps between the fibers. Preferably, defibration is performed so that the bulk density is about 200 g / L or less. Defibration methods include, for example, a method of removing water after immersing in paper and dispersing paper fibers, while crushing paper using an impact crusher such as a hammer (impact) crusher, a sample mill, a mixer, etc. Examples of the method include, but are not limited to, a method of unraveling, and the fiber can be defibrated by a means that a tensile force acts on the paper. When an impact crusher is used, crushing is performed by repeated impact between the impact blade attached to the rotor that rotates at high speed and the repulsion plate, so that the size distribution of the defibrated paper pieces is relatively uniform and finer Since a thing is obtained, a contact area with the chemical | medical agent for liquefaction can be increased. The fiber length of the defibrated paper is preferably about 0.2 to 2 mm, and it is desirable that 50% or more of the fibers are in this range.
[0021]
It is more preferable that the defibrated paper is further broken using a shearing machine or the like so that the fibers are not easily entangled with each other and the workability is improved. In this respect, it is preferable to use pulp sludge or the like that has a short fiber length and cannot be used for papermaking as a liquefied raw material.
[0022]
In addition, wood flour or starch such as corn and rice may be added to the liquefied raw material paper, and it is filled with silica, alumina, talc, etc. with an average particle size of 5 μm or less for the purpose of improving fluidity during liquefaction. Materials may be added.
[0023]
When the defibrated paper is agitated to mix with a liquefied drug having a high viscosity, the fibers tend to be entangled into a lump, and it is bulky, so it is difficult to adjust when combined with the drug. Therefore, the defibrated paper is treated with the liquefaction agent. For example, there are techniques such as applying pressure to the defibrated paper to force it to be immersed in the liquefying chemical, or degassing the defibrated paper by reducing the pressure to infiltrate the liquefied chemical. Thoroughly wet the paper with the liquefying agent. When a kneader or a mixer having a compression function is used, it can be well blended with the liquefying drug. When a kneader is used, kneading by compression, shearing, folding, and convection mixing by twisting the wing is performed between the tip of the rotating blade and the trough, and it can be suitably mixed with the drug, and the liquefaction reaction can proceed as it is. it can.
[0024]
The defibrated paper combined with the liquefying agent as described above is heated to liquefy the paper, and a lignocellulose liquefied product is obtained. The liquefying agent is a mixed solution containing an alkali catalyst or an acid catalyst and one or more liquid compounds selected from a hydroxyphenyl compound, a polyhydric alcohol compound, and a cyclic ester compound.
[0025]
As the hydroxyphenyl compound, for example, phenol, cresol, xylenol, resorcinol, acrylic resorcinol, bisphenol A and the like are preferably used, but are not particularly limited thereto.
[0026]
Examples of the polyhydric alcohol compound include ethylene glycol, propylene glycol, trimethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-hexanediol, 2, 4-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, pinacol, cyclopentane-1,2-diol, cyclohexane-1,4- Dihydric alcohols such as diol, polyethylene glycol, polyoxypropylene glycol, polyoxypropylene-polyoxyethylene glycol, glycerin, trimethylolpropane, triethanolamine, 1,2,6-hexanetriol, pentaerythritol, methyl group Examples thereof include, but are not particularly limited to, trifunctional or higher functional polyhydric alcohols such as sid, sorbitol, mannitol, sucrose and the like, or polyether polyols containing polycaprolactone as a starting material. . Of these, a mixture of glycerin and polyethylene glycol, which is inexpensive and easily available industrially, is particularly preferably used.
[0027]
Further, as the cyclic ester compound, those which can be polymerized by a ring-opening reaction are suitable, for example, propiolactone, β-butyrolactone, α, α′-bischloromethylpropiolactone, α, α-dimethyl-β. -Propiolactone, δ-valerolactone, 1,4-dioxane-2-one, glycolide, trimethyl carbonate, neopentyl carbonate, ethylene oxalate, propion oxalate, ε-caprolactone, α-methyl-ε-caprolactone, β -Methyl-ε-caprolactone, γ-methyl-ε-caprolactone, 4-methyl-7-isopropyl-ε-caprolactone, 3,3,5-trimethyl-ε-caprolactone, cis-disalicylide, trisalicylide, etc. In particular, it is not limited to these. Among these, ε-caprolactone, which is inexpensive, easily available industrially, and easily liquefies paper, is particularly preferably used.
[0028]
Examples of the alkali catalyst include alkali metal oxides such as sodium hydroxide and potassium hydroxide; alkaline earth metal oxides such as calcium hydroxide; alkali metal carbonates such as calcium carbonate; amines such as ammonia or monoethanolamine However, it is not particularly limited to these.
[0029]
Examples of the acid catalyst include inorganic acids, organic acids, Lewis acids and the like, and specifically, for example, sulfuric acid, hydrochloric acid, toluenesulfonic acid, phenolsulfonic acid, aluminum chloride, zinc chloride, boron trifluoride and the like are preferable. Although used, it is not particularly limited to these.
[0030]
In order to promote liquefaction of paper, it is necessary to perform an operation such as stirring or kneading, and it is preferable to use an apparatus having a heating function and a kneading function as the liquefying apparatus. When the defibrated paper is intertwined into a large lump, kneading becomes difficult and the progress of the liquefaction reaction becomes uneven. From this point, a method of mixing the defibrated paper with the liquefaction agent using a kneader and moistening the liquefaction operation as it is is suitable.
[0031]
The heating temperature at the time of liquefaction is about 100 to 200 ° C, preferably about 150 to 190 ° C. The time required for liquefaction varies depending on the degree of stirring and kneading, but is about 5 to 120 minutes when kneading.
[0032]
In this way, the paper is liquefied. A neutralized agent is added to the obtained paper liquefied product, that is, a paper liquefied composition containing lignocellulose liquefied product, and a chemical product is produced using this. For example, it is used as a raw material for urethane paints and urethane adhesives. In addition, isocyanates, catalysts, surfactants, foam stabilizers, foaming agents, fillers, etc. are added and molded by molds, and various molded products such as cushioning materials, heat insulating materials, building materials, RIM, R-RIM. It is possible to produce molded parts of automobile parts, various elastomers, flooring materials and the like. The isocyanate that can be used in this case is generally only required to have two or more -NCO groups, and in particular, use of MDI, TDI, NDI, and H12MDI having low toxicity is preferable.
[0033]
Moreover, when a paper is liquefied using a hydroxyphenyl compound, a normal phenol resin curing agent can be added to the liquefied paper and cured.
[0034]
Since lignocellulose liquefaction proceeds from the contact portion with the liquefaction agent, a large amount of residue remains in the liquefied product when the liquefaction efficiency is low, but liquefaction while kneading the defibrated paper using a kneader or the like As a result, a lignocellulose liquefaction product having a residue rate of 30% or less and a residue content of about 20% by weight or less can be obtained in a liquefaction time of about 5 to 120 minutes. Since the paper to be liquefied is defibrated, the residue remaining in the liquefied product is very fine and the fiber lump does not remain as a residue, so the quality of the chemical product produced using the liquefied product is also improved. Further, even when there is a certain amount of non-liquefied residue, the fiber residue is uniformly dispersed, so that the fiber residue can be used for improving the physical properties of the chemical product.
[0035]
In this way, according to the above-described method, paper liquefaction can be produced in a large amount efficiently and continuously at low cost, and the quality of the obtained liquefaction does not vary, and a stable chemical product can be produced. Can be manufactured.
[0036]
【Example】
Hereinafter, the present invention will be described in detail by way of examples. In the following description, “%” and “part” are weight indications unless otherwise specified.
[0037]
(Example 1)
Used OA paper cut in advance to a 3 cm square was put into a small pulverizer (SK-M2 type, manufactured by Kyoritsu Riko Co., Ltd.) and pulverized. The paper was defibrated by pulverization, and a fibrous pulverized paper having a fiber length of 0.2 mm to 2 mm of 99% or more and a bulk density of 200 g / L was obtained.
[0038]
In addition to 100 parts by weight of fibrous pulverized paper, 140 parts by weight of polyethylene glycol (average molecular weight of about 400), 60 parts by weight of glycerin and 6 parts by weight of sulfuric acid (concentration 97%) were put into a kneader (Dalton, model KM-5). And kneaded at 150 ° C. for 1 hour. As a result, a paper liquefied product was obtained, and the liquefied product obtained was measured for the unliquefied residue rate, the content ratio of the unliquefied residue, and the viscosity of the liquefied product by the following methods. The results are shown in Table 1.
[0039]
[Measurement method of unliquefied residue ratio and non-liquefied residue content ratio]
Ion-exchanged water was added to 2 g of the liquefied sample, diluted, and sufficiently stirred to dissolve, then filtered using a filter paper that had been dried in advance and weighed, and the filtered filter paper was constant at 110 ° C. After drying until it was weighed, the residue weight was obtained from the weight of the filter paper before and after filtration, and the unliquefied residue ratio (%) and the unliquefied residue content ratio (%) were calculated.
[0040]
Unliquefied residue rate (%) = residue weight (g) / feed paper weight (g) × 100
Content ratio of unliquefied residue (%) = residue weight (g) / liquefied material weight (g) × 100
[0041]
[Measurement of viscosity of liquefied product]
The liquefied material sample was put in a 40φ glass container and immersed in a constant temperature bath at 80 ° C. After the temperature became constant, the viscosity was measured with a B-type viscometer (manufactured by Toki Sangyo Co., Ltd.).
[0042]
(Examples 2-3)
The same operation as in Example 1 was repeated except that the amount of fibrous pulverized paper used for liquefaction was changed to 150 parts by weight (Example 2) or 200 parts by weight (Example 3). The unliquefied residue ratio, the content ratio of the unliquefied residue and the viscosity were measured. The results are shown in Table 1.
[0043]
(Examples 4 to 5)
The used OA paper was pulverized in the same manner as in Example 1.
[0044]
Next, as a device for liquefying the fibrous pulverized paper, a universal mixing stirrer (manufactured by Dalton, DMV type) was used. The temperature of the kneading tank of the stirrer was set to 150 ° C., and 150 parts of fibrous pulverized paper (Example) 4) or 200 parts (Example 5), 140 parts of polyethylene glycol (average molecular weight of about 400), 60 parts of glycerol and 6 parts by weight of sulfuric acid (concentration 97%) were added and kneaded at 150 ° C. for 1 hour.
[0045]
As a result, a liquefied product was obtained, and the unliquefied residue ratio, the content ratio of the unliquefied residue, and the viscosity of the obtained liquefied product were measured in the same manner as in Example 1. The results are shown in Table 1.
[0046]
(Example 6)
The paper obtained by cutting the used OA paper (A4) with a shredder into a strip having a width of 5 mm was further finely pulverized using a table crusher. The obtained paper had a bulk density of 200 g / L and was defibrated into a cotton shape.
[0047]
150 parts of this pulverized paper was impregnated with a mixture of 140 parts of polyethylene glycol (average molecular weight of about 400), 60 parts of glycerin and 6 parts of sulfuric acid using a kneader. A paper liquefied product was obtained by putting into the inlet and kneading for 1 hour. The unliquefied residue ratio, the unliquefied residue content ratio, and the viscosity of the obtained liquefied product were measured in the same manner as in Example 1. The results are shown in Table 1.
[0048]
(Example 8)
Using a cutter-type crusher (Morita Seiki Kogyo Co., Ltd., JC-5 type), which is a paper cut from a used OA paper (A4) with a shredder into a 5mm wide strip. Cut. The obtained cut paper was a scale-valve shape, and when this was further finely pulverized by a table crusher, a fibrillated pulverized paper was obtained. When this was observed with a microscope, fibers having a fiber length of 0.2 to 2 mm accounted for 90% or more. The bulk density was 100 g / L.
[0049]
100 parts by weight of the paper thus pulverized together with 140 parts by weight of polyethylene glycol (average molecular weight of about 400), 60 parts by weight of glycerin and 6 parts of sulfuric acid are put into a kneader (Dalton, model KM-5) and mixed. The mixture was kneaded at 150 ° C. for 1 hour. As a result, a paper liquefied product was obtained, and the unliquefied residue rate and the viscosity of the liquefied product were measured for the obtained liquefied product by the same method as in Example 1. As shown in Table 1, the unliquefied residue rate was It was 7.5% and the viscosity was 38 poise.
[0050]
(Example 8)
Prepare pulp sludge discarded from the papermaking process at the paper mill as liquefied raw paper, wash with ion-exchanged water to remove the various processing agents used in the papermaking process, and further dry using a dryer. Water was sufficiently removed from.
[0051]
100 parts by weight of the pulp sludge thus obtained (bulk density 100 g / L), 140 parts by weight of polyethylene glycol (average molecular weight of about 400), 60 parts by weight of glycerin and 6 parts by weight of sulfuric acid, kneader (Dalton, KM-5) ) And kneaded at 150 ° C. for 1 hour to obtain a paper liquefied product.
[0052]
When the unliquefied residue ratio and viscosity of the obtained liquefied product were measured by the method of Example 1, as shown in Table 1, the unliquefied residue ratio was 6.5% and the viscosity was 33 poise. It was.
[0053]
[Table 1]

[0054]
(Comparative Example 1)
Used OA paper (A4) was cut into a 5 mm wide strip with a shredder. Further, it was cut short with scissors. The paper cut in this way was less than 1% when the longest side had a length of 5 mm or less.
[0055]
To 100 parts of the obtained paper, 140 parts of polyethylene glycol (average molecular weight of about 400), 60 parts of glycerin and 6 parts of sulfuric acid are added and put into a kneader (Dalton Co., KM-5 type). Stir for 1 hour. During agitation, especially at the beginning of the agitation when cutting paper was put in, the entangled paper was pinched between the agitator and the container, and the machine generated several abnormal noises and stopped operating several times. The operation continued after untangling the paper.
[0056]
After 1 hour, the resulting mixture was in a liquid state, but a large number of pieces of paper remained were visually observed, and liquefaction was insufficient.
[0057]
(Comparative Example 2)
Used OA paper (A4) was cut into a 5 mm wide strip with a shredder. Further, it was cut short with scissors. The paper cut in this way was less than 1% when the longest side had a length of 5 mm or less.
[0058]
As a paper liquefying apparatus, liquefaction was attempted in the same manner as in Comparative Example 1 by using a desktop extruder having a diameter of 20 mm (produced by Harada Seisakusho Co., Ltd.) adjusted to 170 ° C. instead of the universal mixing stirrer. However, it was difficult for the raw paper to enter the extruder, and most of the raw paper remained at the inlet, and the liquefaction operation did not proceed. Even when the screw speed of the extruder was changed from a low speed of 13 rpm to 30 rpm, the result was the same.
[0059]
Example 9
To 100 parts by weight of the liquefied product obtained in Example 5, 4 parts by weight of imidazole and 2 parts by weight of a foam stabilizer (SZ-1627, manufactured by Nihon Unicar) were added and stirred at high speed for 20 seconds. To this mixture, 75 parts by weight of isocyanate (MDI-100, manufactured by Nippon Polyurethane Industry Co., Ltd.) was added, stirred at high speed for 10 seconds, and poured into a mold prepared in advance to prepare a molded body. By this method, a frame for interior lighting, a cushioning material, a cushioning material for automobile interior, etc. could be produced.
[0060]
(Example 10)
Waste paper mixed with newspapers, magazines, and shredded OA paper was put into an iron tank, and water was added and stirred slowly overnight. The liquid paper was sucked up from the tank, drained, and further dried sufficiently using a dryer. The obtained paper was further cut by a cutter type crusher (Morita Seiki Kogyo Co., Ltd., JC-5 type) equipped with a sieve having a hole diameter of 1 mm. The paper thus cut was a powdered fiber having fluidity that hardly entangled with each other. When observed with a microscope, the content of paper fibers having a fiber length exceeding 1 mm was 7.4%.
[0061]
100 parts by weight of phenol and 3 parts by weight of sulfuric acid together with 100 parts of the cutting paper thus obtained were put into a universal mixing stirrer (manufactured by Dalton, DMV type), and this mixture was stirred at 150 ° C. for 1 hour. When the unliquefied residue rate of the obtained liquefied product was measured by the measurement method of the example, the unliquefied residue rate was 8.2%, and the liquefied product was solid at room temperature.
[0062]
To 100 parts by weight of the obtained solid, 100 parts by weight of silica having an average particle size of 10 μm (trade name NA1, manufactured by Tatsumori Co., Ltd.), 50 parts by weight of glass fiber chip strand having a length of 1 mm (manufactured by Nippon Sheet Glass Co., Ltd.), carnauba 2 parts by weight of wax, 6 parts by weight of calcium hydroxide and 25 parts by weight of hexamethyltetramine as a curing agent were added and mixed for 2 minutes using a Henschel mixer. Further, melt kneading was performed at 120 ° C. for 1 minute using two rolls. The obtained molten mixture was solidified and pulverized at room temperature, and then formed into a 10φ × 10 mm tablet by pressing.
[0063]
By compression molding the tablet-shaped molding material thus obtained, various molded products such as a printed circuit board substrate, a personal computer housing, and a mobile phone housing could be produced. The appearance of the molded product was good and met practical requirements.
[0064]
【The invention's effect】
As is apparent from the above description, according to the present invention, it is possible to efficiently prepare a paper liquefied product from used waste paper at a low cost, and using this, various plastic molded articles having a high use value can be produced. Can be put to practical use. Therefore, it is possible to proceed with the development of recycling use of waste paper and the reduction of the amount of fossil resources used, and its value is extremely great from the viewpoint of resource conservation and effective use.

Claims (4)

  A method of liquefying paper by heating a mixture of at least one liquid compound selected from the group consisting of a hydroxyfunil compound, a polyhydric alcohol compound and a cyclic ester compound, an alkali catalyst or an acid catalyst, and paper. A method for liquefying paper, comprising a step of defibrating the paper to be liquefied in advance.   The defibrated paper has a bulk density of 200 g / L or less, a fiber cone length of 0.2 to 2 mm in fibers of 50% or more of the paper, and the defibrated paper in the mixture in advance. The method for liquefying paper according to claim 1, further comprising a step of wetting.   The paper liquefaction method according to claim 1, wherein pulp sludge is used as the liquefied paper.   A method for producing a molded body, comprising adding a curing agent for isocyanate or a phenol resin to the paper liquefied product liquefied by the paper liquefying method according to any one of claims 1 to 3, followed by curing and molding. .