Patent Publication Number: US-2023145833-A1

Title: Composition of Biodegradable Plant Fiber Raw Material Grains, and Production Method Thereof

Description:
TECHNICAL FIELD 
     The present invention relates to composition components of raw material grains for use in a processing molding machine, and a production method thereof. Particularly, the present invention relates to a production method for producing raw material grains by using a natural plant fiber, starch, and the like as raw materials. 
     BACKGROUND ART 
     Along with the development of scientific technologies, plastic products are further increasing in the modern daily life. Plastics can be produced at low costs, have a variety of characteristics, and are easy to use, thus contributing to the convenience of living. However, if a plastic product is not naturally decomposed and is carelessly thrown away, the plastic product flows into the sea, and is eventually carried by the ocean flows to across the world. As a result, various living organisms in the sea erroneously take in plastics into death or are entangled with plastic products and are thus hindered from moving, or become unable to feed. Such plastics not only bring about damage against the oceanic ecosystem, but also are accumulated in the food chain to consequently harm humans as well. Such marine debris does not only harm the health and the natural ecosystem, but also affect the governments, the life of local people, and leads to economical loss. Particularly, damages on fishing, tourism, and shipping are largest. In addition, most plastics, when heated, generate toxins to harm the human bodies. The best solution is to stop the use of plastic products and to use alternative materials that can be naturally decomposed. Currently, as alternative materials, paper products, products produced using natural materials such as wood and fiber, for example, bowls, cups, straws, bottles, and the like, produced using plant fibers are known. The above fiber material products are produced by using different processing machines for, for example, injection molding, extrusion molding, blow molding, and the like depending on the products. Depending on the technique for processing and molding products, there is a case where the prescription and the production process of raw material grains need to be changed, which is very undesirable for spread of the environmental protection industry, which has been just started. For this reason, how to produce raw material grains for use in different processing machines by using the same raw material prescription and production process has been the development target in the industry. 
     In view of this, the present inventor and others have earnestly conducted studies on the above problem, and actively sought a solution based on the long-term experiences of development and production in the industry. As a result of the long-term research and development, the present inventor and others have successfully developed a “composition of biodegradable plant fiber raw material grains, and a production method thereof” of the present invention for reducing the conventional problems. 
     SUMMARY OF INVENTION 
     A major object of the present invention is to provide a “composition of biodegradable plant fiber raw material grains, and a production method thereof”. The present invention makes it possible to produce raw material grains for use in processing machines for injection molding, extrusion molding, blow molding, and the like through the same production process using the same raw material prescription only by adjusting the blending ratio in production of plant fiber raw material grains. Therefore, the productivity and practicality of environment protection products can be improved. 
     In order to achieve the above object, in the “composition of biodegradable plant fiber raw material grains, and a production method thereof” of the present invention, a blending ratios of raw material grains are 40 to 60% for plant fiber powder, 20 to 30% for starch, 10 to 20% for vegetable gum powder obtained by fermenting starch, 2 to 15% for water-soluble polymer glue, and 1 to 10% for water-soluble cellulose derivative. 
     In addition, the production process includes the following steps. 
     A. &lt;Acquisition of Raw Materials&gt; 
     Raw materials such as the above plant fiber powder, starch, vegetable gum powder obtained by fermenting starch, water-soluble polymer glue, and water-soluble cellulose derivative are acquired. The ratio of each raw material is adjusted as appropriate depending on the processed product of raw material grains, and the processing and molding method. That is, although the prescription for the raw material grains is the same, the ratios are different depending on the processing such as injection molding, extrusion molding, or blow molding. Note that the differences in ratios are adjusted to be within the above ranges for the raw material ratios. 
     B. &lt;Kneading of Fiber Powder&gt; 
     The fiber powder is put into a first kneader, and is rotated and kneaded at a high speed under conditions of 10 to 30 minutes, 40 to 60° C., and 600 to 1200 RPM to soften the fiber powder. 
     C. &lt;Kneading of Starch&gt; 
     The starch and the water-soluble cellulose derivative are put into a second kneader, and are rotated and kneaded at a high speed under conditions of 10 to 20 minutes and 600 to 1200 RPM to activate the fluidity of the powder granules. 
     D. &lt;Kneading of Vegetable Gum Powder&gt; 
     The vegetable gum powder is put into a third kneader, and is rotated and kneaded under conditions of 10 to 40 minutes and a rotation speed of 100 RPM or less to be made viscous. 
     E. &lt;Overall Kneading&gt; 
     The fiber powder, starch, and vegetable gum powder kneaded, and the water-soluble polymer glue are put into a fourth kneader, and are agitated for 10 to 40 minutes while the temperature is set to 40 to 80° C. to uniformly knead a mixed raw material. 
     F. &lt;Molding of Strands&gt; 
     The molding device includes a raw material inlet provided at one end, a raw material outlet provided at the other end, and a transport unit provided between the raw material inlet and the raw material outlet. The mixed raw material is loaded into the molding device, is rotated and agitated while being transported from an end of the raw material inlet to an end of the raw material outlet by using the transport unit and also heated, and is extrusion-molded into a plurality of string-shaped strands through the raw material outlet. 
     G. &lt;Cutting Granulation&gt; 
     The strands are first cooled by using a first cooling system, and then the strands are cut into granular raw material grains by using a cutting unit. 
     H. &lt;Cooling of Raw Material Grains&gt; 
     The raw material grains thus cut are cooled by using a second cooling system, and transported to a storage tub, and are thereafter packaged into products. 
     Therefore, it is possible to produce plant fiber raw material grains for use in different processing machines through the same production process only by adjusting the blending ratio in the above prescription and production process. 
     Hereinafter, the technique, the means, and the advantageous effect of the present invention will be described by giving a preferable embodiment with reference to the drawings so that the above object, configuration, and characteristic of the present invention can be more deeply and specifically understood. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic diagram illustrating processing to obtain strands by kneading in accordance with the raw material prescription of the present invention. 
         FIG.  2    is a schematic diagram illustrating a first cooling system and a cutting unit of the present invention. 
         FIG.  3    is a schematic diagram illustrating a configuration structure of a second cooling system of the present invention and use thereof. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     As shown in  FIGS.  1  to  3   , in a “composition of biodegradable plant fiber raw material grains, and a production method thereof” of the present invention, the blending ratios of the fiber raw material grains are 40 to 60% for plant fiber powder, 20 to 30% for starch, 10 to 20% for vegetable gum powder obtained by fermenting starch, 2 to 15%, and preferably 5 to 10% for water-soluble polymer glue, and 1 to 10%, and preferably 3 to 5% for water-soluble cellulose derivative. The production equipment includes a plurality of kneaders  11 ,  12 ,  13 , and  14 , a molding device  20 , a first cooling system  30 , a cutting unit  40 , and a second cooling system  50 . The production process includes the following steps. 
     A. &lt;Acquisition of Raw Materials&gt; 
     Prescription raw materials for fiber raw material grains are each acquired. The prescription raw materials contain 40 to 60% plant fiber powder, 20 to 30% starch, 10 to 20% vegetable gum powder obtained by fermenting starch, 2 to 15%, and preferably 5 to 10% water-soluble polymer glue, and 1 to 10%, and preferably 3 to 5% water-soluble cellulose derivative, and the like. Among these, the plant fiber powder is obtained by using stem, bark, leaves, pericarp, or the like of a natural plant as a fiber raw material, pulverizing and drying the fiber raw material, and then processing the fiber raw material into a powder having a water content of 20% or less. The grain size of the powder is around 100 to 200 mesh. The starch may be one derived from a plant such as wheat, potato, corn, sweet potato, cassava, lotus root, rice, or algae. The vegetable gum powder is vegetable gum powder obtained by adding a fermenting strain to starch to ferment the starch. The water-soluble polymer glue is general polymer glue for adjusting the viscosity of vegetable gum. The water-soluble cellulose derivative is used to increase the viscosity and is preferably at least one selected from the group consisting of hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, carboxymethyl ethyl cellulose, ethyl hydroxyethyl cellulose, cellulose acetate, methyl cellulose, ethyl cellulose, and cellulose gum. The ratio of each of the above respective raw materials is adjusted as appropriate depending on a planned fabricated processed product of the raw material grains, and the processing and molding method. That is, although the prescription of raw material grains is the same, the ratios are different depending on the processing such as injection molding, extrusion molding, press molding, round bar molding, heat extrusion molding, or blow molding. Note that the difference in ratio is adjusted to be within the above ranges for the raw material ratios. 
     B. &lt;Kneading of Fiber Powder&gt; 
     The fiber powder is put into a first kneader  11 , and is rotated and kneaded at a high speed under conditions of 10 to 30 minutes, 40 to 60° C., and 600 to 1200 RPM to soften the fiber powder. In addition, 2 to 5% bamboo vinegar solution may be added to decompose pesticides remaining in the plant fiber as necessary. 
     C. &lt;Kneading of Starch&gt; 
     The starch and the water-soluble cellulose derivative are put into a second kneader  12 , and are rotated and kneaded at a high speed under conditions of 10 to 20 minutes and 600 to 1200 RPM to activate fluidity of powder granules. 
     D. &lt;Kneading of Vegetable Gum Powder&gt; 
     The vegetable gum powder is put into a third kneader  13 , and is rotated and kneaded under conditions of 10 to 40 minutes and a rotation speed of 100 RPM or less to be made viscous. 
     E. &lt;Overall Kneading&gt; 
     The fiber powder, the starch, and the vegetable gum powder kneaded in the respective steps B, C, and D, and the water-soluble polymer glue are put into a fourth kneader  14 , and are agitated for 10 to 40 minutes while the temperature is set to 40 to 80° C. to uniformly knead the mixed raw material. 
     F. &lt;Molding of Strands&gt; 
     The molding device  20  includes a raw material inlet  21  provided at one end through which the mixed raw material is loaded, and a raw material outlet  22  provided at the other end. The raw material inlet  21  is used to load the mixed raw material. The raw material outlet  22  is provided with a molding extrusion platen  23 , and a plurality of opening holes  231  are formed in the extrusion platen  23 . A transport unit  24  is provided between the raw material inlet  21  and the raw material outlet  22 . The mixed raw material is loaded into the molding device  20 , is rotated and agitated while being transported from an end of the raw material inlet  21  to an end of the raw material outlet  22  by using the transport unit  24  and also heated, and is extrusion-molded into a plurality of string-shaped strands through the extrusion platen  23  to the outside. 
     Moreover, the transport unit  24  includes two power screws  25 , and each of the power screws  25  includes four transport rods  251 ,  252 ,  253 , and  254  separated in multiple stages. A blade  255  is provided on the outer periphery of each transport rod  251 ,  252 ,  253 , or  254 . In addition, the size of the blade  255  of the first transport rod  251  which is located on the raw material inlet  21  side is larger than the blades  255  of the other transport rods  252 ,  253 , and  254 . The size of the blade  255  of the fourth transport rod  254  which is located on the raw material outlet  22  side is smaller than the blades  255  of the other transport rods  251 ,  252 , and  253 . In other words, the blades  255  on the outer peripheries of the transport rods  251 ,  252 ,  253 , and  254  become gradually smaller from the end of the raw material inlet  21  toward the raw material outlet  22 . Note that the temperature of each transport rod  251 ,  252 ,  253 , or  254  is controlled to be 140 to 190° C. by a plurality of temperature adjusting devices (not shown). In addition, in the molding device  20 , a plurality of exhaust pipes  26  are provided at positions corresponding to the first and second transport rods  251  and  252 . The exhaust pipes  26  are connected to a vacuum machine  27 , and water and water vapor are discharged to the outside through the exhaust pipes  26  when the mixed raw material is agitated and transported by the first and second transport rods  251  and  252 . In this way, when the mixed raw material is transported by the transport unit  24 , the mixed raw material is first uniformly agitated by the first and second transport rods  251  and  252 , and then the mixed raw material is gradually extruded to the outside by the third and fourth transport rods  253  and  254  to be molded into string-shaped strands. 
     G. &lt;Cutting Granulation&gt; 
     The strands are first cooled by the first cooling system  30 , and then the strands are cut into granular raw material grains by the cutting unit  40 . The first cooling system  30  includes a transport stage  31 , a power device  32  provided at an end of the transport stage  31 , and a plurality of fans  33  provided above the transport stage  31 . A plurality of rollers  311 , on which the strands are to be placed and moved, are provided on the transport stage  31 . Alternatively, the strands may be transported by a conveyor belt. Note that the power device  32  is a power source for moving the strands, and includes two rolls  321  on the opposite sides in the vertical direction. The two rolls  321  are separated at a certain interval, and can be rotated by a power source  322 . During transportation, after the strands are extrusion-molded, the strands are placed on the transport stage  31 , and the outer peripheries of the strands are sandwiched by the two rolls  321 . As the strands are continually extrusion-molded, the power source  322  is simultaneously operated to move the strands on the transport stage  31 . While the strands are moved, air is blown by the fans  33  to cool the strands. 
     Moreover, the cutting unit  40  is provided outside the adjacent two rolls  321 . A motor  42  is provided on a cutter table  41 , and a cutter blade  43  is rotated by the motor  42 . The radius of the cutter blade  43  is larger than the width of the surface of the transport stage  31 . The strands are moved through between the two rolls  321  and are cut into raw material grains by the rotating cutter blade  43 . In addition, a slide rail  44  is provided between the bottom of the motor  42  and the cutter table  41 . By moving the motor  42  on the slide rail  44 , the cutting position of the cutter blade  43  can be adjusted. 
     H. &lt;Cooling of Raw Material Grains&gt; 
     The raw material grains thus cut are cooled by the second cooling system  50  while being transported. The second cooling system  50  includes a raw material collecting tub  51 , a first blower  52 , a first cooling tub  53 , a second cooling tub  54 , a second blower  55 , and a storage tub  56 . A first conduit  57  is provided between the raw material collecting tub  51  and the first cooling tub  53 , a first second conduit  58  is provided between the first cooling tub  53  and the second cooling tub  54 , and a third conduit  59  is provided between the second cooling tub  54  and the storage tub  56 . In addition, the first blower  52  is provided at an appropriate position in the first conduit  57 . The second blower  55  is provided at an appropriate position in the third conduit  59 . After the raw material grains are cut and molded, the raw material grains drop or are put into the raw material collecting tub  51 . Then, after the raw material grains are sent into the first cooling tub  53  by the first blower  52 , the raw material grains inside the first cooling tub  53  are sent into the storage tub  56  by the second blower  55 . A raw material drop opening  561  is provided in the bottom portion of the storage tub  56 , so that the packaging work can be conducted by placing a packaging bag below the raw material drop opening  561 . Hence, the present invention makes it possible to improve the efficiency in producing and manufacturing plant material grains by producing plant fiber raw material grains for use in different processing machines through the same production process only by adjusting the blending ratio in the above prescription and production process, and is useful in promoting the development of the industry. 
     In summary of the above, the present invention involves an excellent inventive step and practicality as compared with products of the same type. In addition, as a result of investigating domestic and overseas technical data and documents on similar configurations, it has not been found that the same structure existed previously. Hence, the present invention has novelty. Therefore, a patent application is going to be filed in compliance with the law. 
     The above embodiment is only an example for explaining the present invention. It goes without saying that modifications, improvements, and applications made by a person skilled in the art based on the embodiment without departing from the spirit of the present invention are encompassed within the scope of claims of the present invention. 
     REFERENCE SIGNS LIST 
     
         
           11  first kneader 
           12  second kneader 
           13  inside of third kneader 
           14  inside of fourth kneader 
           20  molding device 
           21  raw material inlet 
           22  raw material outlet 
           23  extrusion platen 
           231  opening hole 
           24  transport unit 
           25  power screw 
           251  first transport rod 
           252  second transport rod 
           253  third transport rod 
           254  fourth transport rod 
           255  blade 
           26  exhaust pipe 
           27  vacuum machine 
           30  first cooling system 
           31  transport stage 
           311  roller 
           32  power device 
           321  roll 
           322  power source 
           33  fan 
           40  cutting unit 
           41  cutter table 
           42  motor 
           43  cutter blade 
           44  slide rail 
           50  second cooling system 
           51  raw material collecting tub 
           52  first blower 
           53  first cooling tub 
           54  second cooling tub 
           55  second blower 
           56  storage tub 
           561  raw material drop opening 
           57  first conduit 
           58  second conduit 
           59  third conduit