JP4305129B2 - Bacteria bed bag filter and bacteria bed container or fungus bed bag using the same - Google Patents

Description

  The present invention relates to a filter for a fungus bed bag, and a fungus bed container or a fungus bed bag using the same. Specifically, when storing and cultivating fungus beds such as shiitake mushroom, maitake mushrooms, agarisuka, beech shimeji, enoki mushrooms, sea cucumbers, mushrooms, oyster mushrooms, mushrooms, etc. The present invention also relates to a fungus bed container or a fungus bed bag for mycelium culture using the same.

  As a conventional cultivation method of edible fungi, seasonal wood cultivation is carried out in a natural environment, but recently, the promotion cultivation fungus bed cultivation method that can be cultivated year-round with the spread of air conditioning equipment has become popular It has become. Bacteria bed cultivation is a method of cultivation in plastic bottles or bags, usually called fungus bed containers or fungus bed bags, and mainly ocago, rice bran or bran with different particle sizes made from hardwood. A medium in which the Videl (nutrient) is mixed at an appropriate ratio with a mixer and the water content is adjusted to 60 to 65% is used. For cultivation, after filling the medium in the container for the fungus bed or the bag for the fungus bed, sterilize the medium by high-pressure steam sterilization, etc., inoculate the inoculum in a clean room after cooling, and then culture the fungus in the culture room Has been done.

The high-pressure steam sterilization is performed to prevent germs from growing on the medium. In the so-called high-pressure sterilization method, the medium is heated to about 120 ° C. for about 1 to 2 hours under a pressure of about 0.12 MPa. Then, deaeration treatment is performed. Moreover, in the normal pressure sterilization method, it is normally performed in a sterilization pot at a medium temperature of about 95 to 100 ° C. for 6 to 10 hours.
When using a container for fungus beds, culture with the stoppers sealed in the opening of the container. However, if the stoppers are too tight, the amount of air supply required to grow the bacteria will be insufficient, and if it is too weak, Penicillius (Aochobi) In addition, there are problems such as invasion of various germs such as Trichoderma, or invasion of hyphae and spores other than the hyphae to be cultured, which requires very skill and labor.

  On the other hand, when using a bag for fungus beds, culturing in a state where the opening of the bag is sealed with a heat seal or various jigs, it is necessary to supply the air necessary for growing the fungus, In general, a vent hole is provided in the upper part of the fungus bed main body, and this hole is covered with a filter for a fungus bed bag through which air passes but does not pass various bacteria. In such a fungus bed bag, air is supplied from the vent through the fungus bed filter, but invasion of various germs and dust is prevented by the fungus bed filter. When a medium containing moisture comes into contact with the filter for the mycelia bag, miscellaneous bacteria and mycelia and spores other than the mycelia to be cultured may be easily mixed. There are no pores.

When using a bag for fungus beds, it is not necessary to apply a tight stopper, so skill is not required, and there is no need for trouble, but since the vent is provided only in the upper part, air supply to the medium located in the lower part If the amount of the filter is clogged for some reason during sterilization or culture, sufficient air will not be supplied to the fungus bed, which will adversely affect growth.
Bacteria grow gradually from the upper part of the inoculated medium toward the lower part and vary depending on the type of bacteria, but the bacteria spread throughout the medium over a certain period of time. Therefore, it is desirable to supply air not only from the upper part of the fungus bed bag but also from the lower part in order to spread the bacteria quickly throughout the medium.

  As a conventional filter for a fungus bed bag, a porous plastic filter, a nonwoven fabric filter, a filter having a perforated type hole, and the like have been proposed. Porous plastic filters have been disclosed in various manufacturing methods. After making a thin film by mixing an elution substance into a polymer, the elution substance is eluted and removed from the film to make pores. In contrast, a method of using a liquid acting as a non-solvent as a coagulant, a method of removing a solvent from a polymer solution containing a polymer, a solvent and a non-solvent, and then removing the non-solvent to create pores. In a method in which the voids in the particles are made into pores by mixing the polymer, a method in which a part of the film is damaged by irradiating radiation and the part is dissolved and removed to make the pores, and the swelling substance is swollen After mixing with the polymer and drying, the voids due to volume shrinkage are made into pores, and after a crystalline polymer film is stretched under specific conditions to develop a lamellar structure, heat is applied in a state where appropriate elongation deformation is applied. Fixed A method of developing macrovoids, a method of forming fine pores by stretching a film made by adding a fine powdery inorganic filler to a polymer, and having fine pores by melting and blowing fine fibers of several microns It is a method to make a sheet.

  Bacteria bed bags (for example, refer to Patent Document 1) in which pores (0.01 to 0.3 μm) having a filter action against various germs are formed sufficiently supply air necessary for the growth of the germs. However, there is a disadvantage that the growth of bacteria is insufficient. Bacteria bed bags having a pore size of 0.01 to 100 μm (see, for example, Patent Documents 2, 3, and 4) can sufficiently supply air necessary for the growth of bacteria, but 1 to 10 μm of Penicillus (Aochobi) There are drawbacks such as invasion of bacteria such as Trichoderma or invasion of mycelia and spores other than the mycelium to be cultured.

  On the other hand, component A composed of ethylene-propylene block copolymer, component B composed of polypropylene homopolymer or random copolymer, and component C composed of low molecular weight polypropylene, and optionally composed of component D composed of calcium carbonate and beta spherulite nucleating agent A porous membrane made of a polymer composition to which component E is added is disclosed (for example, see Patent Document 5). In these technologies, the ethylene-propylene block copolymer alone does not exhibit sufficient porosity and gas permeability, so improvement is made with a multi-component system. However, since these components are multi-component, they are uniformly dispersed. Otherwise, it is difficult to obtain a uniform porous film. Moreover, when the pores formed in the porous membrane have a large diameter and are used as a filter for a mycelia bag, invasion of miscellaneous bacteria such as Penicillius (Ao mold) and Trichoderma, or hyphae other than the hyphae to be cultured, It has problems such as the invasion of spores and the like, and is difficult to use as a filter for fungus bed bags.

As the nonwoven fabric filter, a nonwoven fabric filter produced by a known method such as a spunbond method, a melt blow method, a flash spinning method, or a dry card method using a thermoplastic resin as a raw material is known. In any case, the air necessary for the growth of fungi can be sufficiently supplied, but the pore size of the filter is as large as 1 μm or more. Invasion of various germs such as 1-10 μm penicillus (Trichoderma) or Trichoderma, or mycelium other than the mycelium to be cultured There are drawbacks such as invasion of spore and spores.
The perforated type filter for bacteria bed bag can supply enough air necessary for the growth of bacteria, but the pore size of the filter is as large as 100-450μm, and it is also difficult for bacteria such as Penicillius (Aochabi) Trichoderma having 1-10μm There are disadvantages such as invasion or invasion of mycelia or spores other than the mycelium to be cultured.

Japanese Utility Model Publication No. 57-22518 JP 55-85331 A JP-A-9-187168 Japanese Patent Laid-Open No. 9-248059 JP-A-4-309546

  An object of the present invention is to solve the above problems and to have high gas permeability in a state in which invasion of germs such as Penicillius (Aochobi) and Trichoderma, and hyphae and spores other than the hyphae to be cultured is prevented. For this reason, the air necessary for the growth of the fungus can be sufficiently supplied to the lower part of the culture medium, which can shorten the cultivation period, improve the fruit body quality and increase the yield, and has a simple composition. Nevertheless, it is an object of the present invention to provide a fungus bed bag filter and a fungus bed container or a fungus bed bag excellent in productivity.

  As a result of intensive studies, the inventors of the present invention contain a polyolefin resin (C) composed of crystalline polypropylene (A) and a propylene-α-olefin copolymer (B) dispersed in the crystalline polypropylene (A). A filter formed by melting and kneading a resin composition to form a film-like melt and stretching the film-like molding in at least one direction, and having pores communicating with the copolymer (B) region The present invention has been completed based on the finding that this problem is solved by a filter for a fungus bed bag and a fungus bed container or a fungus bed bag using the same. In the present invention, the pores communicating with each other means pores that are continuously formed in the copolymer (B) region, and as a result, connect the both surfaces of the filter for the fungus bed bag.

The present invention is constituted by the following.
1. A resin composition containing a polyolefin resin (C) composed of crystalline polypropylene (A) and a propylene-α-olefin copolymer (B) dispersed in the crystalline polypropylene (A) is melted and kneaded to form a film. A filter formed by forming a film-like melt, forming the film-like melt into a film-like molding, and then stretching the film-like molding in at least one direction, wherein the polyolefin resin (C) is crystalline. Polypropylene (A) is composed of 30 to 90% by weight and propylene-α-olefin copolymer (B) is composed of 10 to 70% by weight, and polyolefin resin (C) produces crystalline polypropylene (A) in the first stage. And a draft obtained when a film-like melt is formed into a film-like molded article obtained by a multi-stage polymerization method including a step of continuously producing the propylene-α-olefin copolymer (B) in the second stage. The ratio is in the range of 1 to 10,
A filter for a fungus bag having pores communicating with the copolymer (B) region.

2. The melt flow rate ratio MFR _PP / MFR _RC of the melt flow rate MFR _PP of the crystalline polypropylene (A) and the melt flow rate MFR _RC of the propylene-α-olefin copolymer (B) is 0.1 to 10. 2. The filter for a fungus bed bag according to 1 above.

3. 3. The filter for a fungus bed bag according to 2 above, wherein the melt flow rate ratio MFR _PP / MFR _RC is 0.2 to 5.

4). Any one fungal bed bag filter according wherein said 1-3, wherein, wherein the draft ratio at the time of forming the film-like melt film-shaped molded product is in the range of 1-3.

5. Any one of said 1-4 characterized by polyolefin resin (C) consisting of crystalline polypropylene (A) 40 to 70 weight% and polypropylene-alpha-olefin copolymer (B) 30 to 60 weight%. The filter for fungus bed bags according to 1.

6). 6. The fungus bag filter according to any one of 1 to 5, wherein the propylene content of the propylene-α-olefin copolymer (B) is 30 to 80% by weight.

7). The filter for bacterial bed bags according to any one of 1 to 6 above, wherein the propylene content of the propylene-α-olefin copolymer (B) is 40 to 70% by weight.

8). 8. The filter for a bacterial bed bag according to any one of 1 to 7 above, wherein the air permeability resistance (Gurley) is 10 to 300 seconds / 100 ml and the pore diameter measured by ASTM F316 method is 0.1 to 1 μm.

9. A resin composition containing a polyolefin resin (C) composed of crystalline polypropylene (A) and a propylene-α-olefin copolymer (B) dispersed in the crystalline polypropylene (A) is melted and kneaded to form a film. A filter formed by forming a film-like melt, forming the film-like melt into a film-like molding, and then stretching the film-like molding in at least one direction, wherein the polyolefin resin (C) is crystalline. It consists of 30 to 70% by weight of polypropylene (A) and 30 to 70% by weight of propylene-α-olefin copolymer (B) to produce crystalline polypropylene (A) in the first stage, and continuously in two stages. It is obtained by a multistage polymerization method including a step of producing a propylene-α-olefin copolymer (B), and a draft ratio when forming a film-like melt into a film-like molding is in the range of 1 to 10. , Filters for mushroom bed bag having pores communicating with the polymer (B) region.

10. The melt flow rate ratio MFR _PP / MFR _RC of the melt flow rate MFR _PP of the crystalline polypropylene (A) and the melt flow rate MFR _RC of the propylene-α-olefin copolymer (B) is greater than 10 and 1,000 or less. 10. The filter for a fungus bed bag according to 9 above.

11. 11. The filter for a bacterial bed bag according to 9 or 10 above, wherein the draft ratio when the film-shaped melt is formed into a film-shaped product is in the range of 1 to 5.

12 The filter for a fungus bed bag according to any one of 9 to 11 above, wherein the propylene content of the propylene-α-olefin copolymer (B) is 30 to 80% by weight.

13. The filter for a fungus bed bag according to any one of 9 to 11 above, wherein the propylene content of the propylene-α-olefin copolymer (B) is 40 to 70% by weight.

14 14. The filter for a bacterial bed bag according to any one of 9 to 13, wherein the air permeability resistance (Gurley) is 50 to 500 seconds / 100 ml and the pore diameter measured by ASTM F316 method is 0.5 to 1 μm.

15. A container for fungus beds or a bag for fungus beds using the filter for fungus bed bags according to any one of 1 to 14 above.

  Since the filter for a fungus bed bag of the present invention has a small pore diameter and a long communication hole, the gas permeability can be increased in a state in which contamination by bacteria and other bacteria is prevented. Necessary air can be sufficiently supplied, and air can also be sufficiently supplied to the lower part of the medium, thereby shortening the cultivation period, improving fruit body quality and increasing yield. In addition, the filter for fungus bed bag and the container for fungus bed or the bag for fungus bed of the present invention has a simple composition and easy uniform dispersion in the production process. Bacteria bed filter and fungus bed container or fungus bed bag.

Hereinafter, embodiments of the present invention will be described.
(1) Polyolefin resin The filter for a fungus bed bag of the present invention includes crystalline polypropylene (A) and a propylene-α-olefin copolymer (B) (hereinafter simply referred to as “copolymer (B)”). And a polyolefin resin (C) in which the copolymer (B) is finely dispersed as a region in the matrix of the crystalline polypropylene (A).

(I) Crystalline polypropylene (A)
The crystalline polypropylene (A) is a crystalline polymer mainly composed of propylene polymerized units, preferably polypropylene having 90% by weight or more of propylene polymerized units. Specifically, it may be a propylene homopolymer, or may be a random or block copolymer of 90% by weight or more of propylene polymer units and 10% by weight or less of α-olefin. As the α-olefin used when the crystalline polypropylene (A) is a copolymer, ethylene (included in the α-olefin in the present invention), 1-butene, 1-pentene, 1-hexene, 1-octene, Examples include 1-decene, 1-dodecene, 4-methyl-1-pentene, and 3-methyl-1-pentene. Among these, it is preferable from the viewpoint of production cost to use a propylene homopolymer or a propylene-ethylene copolymer having a propylene polymer unit content of 90% by weight or more.

The melt flow rate MFR _PP of the crystalline polypropylene (A) is preferably in the range of 0.1 to 50 g / 10 min from the stability of film formation.

(ii) Propylene-α-olefin copolymer (B)
The copolymer (B) is a random copolymer of propylene and an α-olefin other than propylene. The content of propylene polymerized units is preferably in the range of 30 to 80% by weight, more preferably 40 to 70% by weight, based on the weight of the entire copolymer (B). When the content of the propylene polymerized unit is within the above range, pores are easily formed in the copolymer (B) region existing in the matrix of the crystalline polypropylene (A), and the copolymerized with the crystalline polypropylene (A). Since the interfacial peeling of the combined body (B) is difficult to occur, a filter for a fungus bed bag having good low-temperature stretchability and a small pore diameter is obtained.

  Examples of the α-olefin other than propylene used in the copolymer (B) include ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, and 4-methyl-1. -Pentene, 3-methyl-1-pentene, etc. are mentioned. Among these, a propylene-ethylene copolymer using ethylene as an α-olefin is preferably used from the viewpoint of production cost.

The melt flow rate MFR _RC of the copolymer (B) is not particularly limited, but a range of 0.1 to 20 g / 10 min is preferable because of excellent molding processability.

(iii) Polyolefin resin (C)
The polyolefin resin (C) is composed of crystalline polypropylene (A) and a copolymer (B). The melt flow rate ratio MFR _PP / MFR _RC (hereinafter referred to as “MFR ratio”) between the melt flow rate MFR _PP of the crystalline polypropylene (A) and the melt flow rate MFR _RC of the copolymer (B) is not particularly limited. However, 0.1 to 1,000 is preferable from the viewpoint of moldability.

Among them, when the MFR ratio is 0.1 to 10, preferably 0.2 to 5, the copolymer (B) is more uniformly and finely dispersed in the crystalline polypropylene (A). When the stretching treatment (C) is performed, uniform and fine pores are formed in the copolymer (B) region dispersed in the crystalline polypropylene (A), and as a result, an excellent fungus bed with high gas permeability. A bag filter is obtained.
Further, when the MFR ratio is greater than 10 and 1,000 or less, the pore diameter of the pores formed by stretching is larger than that when the MFR ratio is 0.1 to 10, and the proportion of the pores communicated is Since the air resistance is lowered and the air resistance is increased, the air supply amount for growing bacteria tends to decrease and the growing period tends to increase, but the resin composition is less susceptible to fluctuations in film forming conditions and stretching conditions, so the characteristics are stable. It is easy to obtain a filter for a fungus bed bag.

  The filter for a bacterial bed bag of the present invention preferably has a gas permeability index (Gurley) of 10 to 500 seconds / 100 ml and a pore diameter of 0.1 to 1 μm. If the air permeability resistance and pore diameter are within the above ranges, the air necessary for the growth of the bacteria can be supplied sufficiently, and it is difficult for bacteria and bacteria to invade, so it is contaminated with bacteria such as Penicillius and Trichoderma. It is hard to be done.

  The content of the crystalline polypropylene (A) in the polyolefin resin (C) is 30 to 90% by weight, preferably 40 to 70% by weight when the MFR ratio is 0.1 to 10, and the copolymer (B ) Is 10 to 70% by weight, preferably 30 to 60% by weight. When the content of the copolymer (B) is less than 10% by weight, it is difficult to obtain the continuous pores of the present invention because the continuous pores formed in the copolymer (B) region is reduced. When it exceeds 70% by weight, it is difficult to obtain a dispersion structure of the copolymer (B) present in the crystalline polypropylene (A).

  When the MFR ratio is greater than 10 and 1,000 or less, the content of the crystalline polypropylene (A) in the polyolefin resin (C) is 30 to 70% by weight, preferably 40 to 60% by weight. The content of the α-olefin copolymer (B) is 30 to 70% by weight, preferably 40 to 60% by weight. If the content of the crystalline polypropylene (A) and the copolymer (B) is in the above range, the dispersibility of the copolymer (B) from which continuous pores are obtained is good.

In the method for producing the polyolefin resin (C) , the crystalline polypropylene (A) is produced in the first stage, and then the copolymer (B) is produced in the presence of the crystalline polypropylene (A) in the second stage, This is a method for continuously producing a polyolefin resin (C). This continuous polymerization method is lower in production cost than the melt mixing method described above, and a polyolefin resin (C) in which the copolymer (B) is uniformly dispersed in the crystalline polypropylene (A) can be stably obtained. Therefore, it is preferable.

In order to obtain the polyolefin resin (C) having the MFR ratio as described above by a continuous polymerization method, specifically, a method described in International Publication No. 97/19135, JP-A-8-27238, or the like is used. Can be used.
In addition, the polyolefin resin (C) can be produced by the above-described method, and one having a desired specification may be selected from commercially available products.

The MFR ratio is usually determined by measuring MFR _PP of the crystalline polypropylene (A) and MFR _RC of the copolymer (B). However, when the polypropylene resin is continuously produced by multistage polymerization (when the crystalline polypropylene (A) is first polymerized and then the copolymer (B) is polymerized), the MFR _{RC of the} copolymer (B) is used. Of MFR _PP of crystalline polypropylene (A) that can be directly measured, melt flow rate MFR _{WHOLE of} the resulting polyolefin resin (C), and content of copolymer (B) in polyolefin resin (C) The MFR ratio can be obtained by calculating MFR _RC from W _RC (weight%) by the following formula.
log (MFR _RC ) = {log (MFR _WHOLE ) − (1−W _RC / 100) log (MFR _PP )} / (W _RC / 100)

  In the filter for fungus bed bags of the present invention, many fine cleavages are observed in the copolymer (B) region dispersed in the crystalline polypropylene (A). Since the copolymer (B) contains a propylene component, the copolymer (B) is compatible with crystalline polypropylene. The copolymer (B) having compatibility with the crystalline polypropylene (A) is a crystalline polypropylene ( Since the strength is lower than A), it is presumed that cleavage occurred in the copolymer (B) region by stretching. This mechanism is fundamentally different from the conventional multicomponent stretching method in which inorganic fillers and different polymers are mixed and stretched. As a result, the obtained filter for a fungus bed bag has a small pore diameter, a long communication hole, and a large effect of preventing invasion of bacteria and bacteria.

In the present invention, the copolymer (B) region means a region occupied by the copolymer (B) itself. Thus, the pores occurring in the copolymer (B) region, a pore by cleavage occurring in a region occupied by the copolymer (B) itself.

(2) Resin composition for filter formation for fungus bed bags The resin composition, which is a molding material of the film-like molded product for forming the filter for fungus bed bags of the present invention, is usually in addition to the polyolefin resin (C). Antioxidants, neutralizers , hindered amine weathering agents, UV absorbers, antifogging agents, antistatic agents, surfactants , lubricants, antiblocking agents, antibacterial agents, antifungal agents, pigments Etc. can be blended as required.

  In addition, the resin composition for forming the filter for a fungus bed bag of the present invention includes a propylene homopolymer and a monomer other than propylene containing propylene as a main component within a range not impairing the effects of the present invention. Two or more random polymers, and other olefin resins such as polyethylene resin, polybutene resin, and polymethylpentene resin may be used in combination.

  Further, an ethylene-diene elastic copolymer, ethylene-propylene elastic copolymer, styrene polymerized with a single site catalyst or a known multi-site catalyst in order to lower the softening temperature of the resin composition or improve flexibility. -An elastic copolymer such as a butadiene elastic copolymer may be added.

  The method for blending the polyolefin resin (C) and the above additives is not particularly limited, and is blended by a usual blending device such as a mixer with a high-speed stirrer such as a Henschel mixer (trade name), a ribbon blender, and a tumbler mixer. A method (dry blending) can be exemplified, and further a pelletizing method using a normal single screw extruder or twin screw extruder can be exemplified.

(3) Formation of filter for fungus bed bag The filter for fungus bed bag of the present invention is obtained by melting and kneading the resin composition mainly composed of polyolefin resin (C) to form a film-like melt. It can be formed by forming a product into a film-shaped product in a draft ratio of 1 to 10 and then stretching the film-shaped product in at least one direction at a temperature of 100 ° C. or lower. The process consists of a film forming process and a stretching process. The main component is the most abundant component.

(i) Film-forming process For the film-forming process for obtaining a film-shaped molded product from the resin composition, a known method such as an inflation film molding method, a T-die film molding method, or a calendar molding method is used.

  The resin composition can be formed at an extrusion molding temperature of 180 ° C. or higher, but the purpose is to reduce the pressure inside the die and reduce the draft ratio described later, and the rigidity of the crystalline polypropylene (A) as a matrix. An extrusion temperature of 220 to 300 ° C. is suitably used in order to improve and facilitate the formation of uniform pores in the copolymer (B) region dispersed in the crystalline polypropylene (A).

The melt-kneaded resin composition is extruded from the die lip. At this time, the linear velocity V _{CL in} the flow direction (MD) of the resin composition passing through the die lip and the flow direction (MD) line of the film-shaped molded product The draft ratio (V _CL / V _f ) defined by the ratio of the speed V _f is an important factor for achieving the present invention. Generally, the draft ratio is about 10 to 50 when a thermoplastic resin film is formed. In the present invention, the draft ratio at the time of film formation of the resin composition is 1 to 10, among them, when MFR ratio is 0.1 to 10, the 1-3 good Mashiku, MFR ratio is from 10 It is large when the 1,000, 1-5 good preferable. When the draft ratio is within the above range, the obtained film-shaped molded article is excellent in stretchability, and fine communicating pores are easily formed by stretching.

  According to the above method, even in the polyolefin resin (C) in which continuous pores are difficult to be obtained in a general draft ratio, it is possible to form continuous pores, and the polyolefin resin (C) is made of crystalline polypropylene (A ) And propylene-α-olefin copolymer (B) alone, the obtained filter for fungus bed bag has sufficient gas permeability.

In the case of an inflation film molding method, in addition to the draft ratio, a filter obtained by a blow ratio L _f / L _m represented by a ratio of a circumferential length L _f of the inflation film and a circumferential length L _m of the circular lip Although gas permeability changes, if the draft ratio is within the above range, a blow ratio in the range of about 1 to 10 is preferably used. If the blow ratio is within the above range, stable production of the film-shaped molded product is possible, and the resulting film-shaped molded product can be easily made porous.

  A film extruded from a die lip in order to improve the rigidity of the crystalline polypropylene (A) as a matrix and to easily form uniform pores in the copolymer (B) region dispersed in the crystalline polypropylene (A). The cooling of the shaped product is desirably slow cooling, and in the T-die molding method, the temperature of the cooling roll is desirably 60 to 120 ° C, more preferably 70 to 110 ° C. If the temperature of the chill roll is within the above range, the desired filter for microbial bed bags can be easily obtained, and there is no fear that the molten resin will adhere to the roll and impair the productivity. Also, in the inflation molding method, the molten cylindrical body extruded from the die lip is usually cooled with air, but the cylindrical body is gradually cooled by lowering the air volume or heating the air. Is desirable.

  The thickness of the film-like molded product obtained in the film-forming process is not particularly limited, but is determined by the required characteristics of the stretching and heat treatment conditions in the next stretching process and the use of the filter for the fungus bed bag, from 20 μm to The thickness is 2 mm, preferably about 50 μm to 500 μm, and the film forming speed is suitably in the range of 1 to 100 m / min. The film-shaped moldings having these thicknesses are composed of a combination of an inflation molding apparatus, an air knife having the cooling roll and an air outlet, the cooling roll and a pair of metal rolls, the cooling roll and a stainless belt, and the like. It can be obtained by various film forming apparatuses such as a T-die film forming apparatus and a calendar forming apparatus.

  Furthermore, the filter for fungus bed bags of the present invention is obtained by coextruding a resin composition containing a known inorganic filler, organic filler, etc. with the resin composition for forming the filter for fungus bed bags of the present invention. A film-like molded product may be used. In this case, the polymer constituting the resin composition containing a filler or the like is preferably a polyolefin resin such as a polypropylene resin or a polyethylene resin from the viewpoint of compatibility.

  In addition, you may heat-process in order to further improve a crystallinity degree before using for the obtained film-form molding to the next extending process. The heat treatment is performed, for example, by heating at a temperature of about 80 to 150 ° C. for about 1 to 30 minutes with a heated air circulation oven or a heating roll.

(ii) Stretching process The film-shaped molded product formed in the film-forming process is then stretched in at least one of the machine direction (MD) direction or the transverse (TD) direction, and into the crystalline polypropylene (A). Fine pores communicating with the finely dispersed propylene-α-olefin copolymer (B) region are formed.

  In addition to the uniaxial stretching method of stretching in one direction, the stretching method includes a sequential biaxial stretching method of stretching in the other direction after stretching in one direction, a simultaneous biaxial stretching method of stretching simultaneously in the longitudinal and transverse directions, and A method of performing multi-stage stretching in a uniaxial direction or a method of further stretching after sequential biaxial stretching or simultaneous biaxial stretching may be used, and any method may be used.

The first stage stretching temperature is preferably lower than the melting point T _mα of the copolymer (B), and a temperature range of 10 to 100 ° C. is preferably used. In the present invention, the polyolefin resin (C) It has been found that the composition has excellent stretchability in these low temperature regions. The draw ratio is not particularly limited and is determined from the required properties of the second-stage draw conditions performed as necessary and the use of the filter for the fungus bed bag, but is usually excellent in the range of 1.5 to 4 times. A filter for a fungus bed bag having excellent characteristics is obtained, and there is no fear of a decrease in productivity due to frequent stretching.

The filter for the fungus bed bag of the present invention performs the second-stage stretching in the direction perpendicular to the first stage, if necessary, when the air permeability is further required, but the second-stage stretching temperature is The melting point T _{mc of} the crystalline polypropylene (A) is preferably 10 ° C. or more lower. Moreover, when this _{extending | stretching} temperature is higher than melting _| fusing point Tm ( _alpha ) of a copolymer (B), there exists a tendency for the porosity not to increase so much and to reduce the thickness of the filter for microbial bed bags obtained. Furthermore, when the _stretching temperature is lower than T _mα , the porosity increases, but the thickness tends not to decrease much.

The draw ratio of the second stage is determined by characteristics such as required air permeability, but when the MFR ratio is 1 to 10, the drawability is higher than when the MFR ratio is greater than 10 and 1,000 or less. Is usually in the range of 1.5 to 7 times. When the MFR ratio is greater than 10 and 1,000 or less, the draw ratio is usually in the range of 1.5 to 4 times.
If the draw ratio is within the above range, the drawing effect is sufficient, and there is no possibility that the productivity is lowered due to the drawing being cut.

  It is preferable that the membrane-shaped molded product that has been formed into pores by the above stretching step and then becomes porous is then heat-treated. This heat treatment is mainly intended for heat fixation for maintaining the formed pores, and is usually carried out on heating rolls, between heating rolls or through a hot air circulating furnace.

This heat treatment (heat setting) heats the film-shaped molded product having pores while maintaining the stretched state to a temperature lower by 5 to 60 ° C. than the melting point T _mc of the crystalline polypropylene (A), and reduces the relaxation rate to 0 to 50. It is carried out by making into%. When the heating temperature is within the above range, the formed pores are not blocked and the heat setting is sufficiently performed.

  The thickness of the filter for a fungus bed bag of the present invention is not particularly limited, but is preferably 10 to 100 μm, more preferably 30 to 50 μm from the viewpoint of productivity and flexibility.

  The filter for fungus bed bags of the present invention can be used as a filter material for fungus bed bags by bonding a known non-woven fabric or woven fabric in the same manner as a general filter, but the filter for fungus bed bags of the present invention has high strength. In addition, since the weight can be reduced, the thickness can be increased to some extent, so that a sufficient strength can be obtained by itself, which is economically advantageous.

  Although there is no restriction | limiting in particular as a nonwoven fabric, For example, 1 or more types can be suitably selected and used from well-known nonwoven fabrics, such as a spun bond nonwoven fabric, a spunlace nonwoven fabric, a hot air guard nonwoven fabric, a hot emboss guard nonwoven fabric, a melt blown nonwoven fabric. A known method such as hot embossing, ultrasonic sealing, or hot melt is used for bonding the filter and the nonwoven fabric.

(4) Bacteria bed container or fungus bed bag The method for attaching the filter for fungus bed bag of the present invention to the fungus bed container or fungus bed bag is to remove a part of the container or bag and remove it to that part. For example, there is a method in which a filter for a bacterial bed bag that is one size larger than the above portion is attached by an adhesive or heat bonding. It is also possible to paste a filter for a fungus bed in advance on a part of the film and then make a bag into the bag for the fungus bed. The shape of the filter for the bacteria bed bag to be attached is not particularly limited, and may be any shape such as a round shape, a square shape, or a linear shape. Further, one or two or more places may be used per one container or bag. The size of the filter portion for the fungus bed bag preferably has an area of 0.1 to 1% of the surface area of the container or bag. As an example of this method, a bacterium cut into 5 to 7 cm square so as to cover the perforated portion by drilling a hole having a diameter of 2 to 3 cm in one to several places on the side surface of the container or bag. The filter for floor bags can be thermocompression bonded with a circular heat sealer of 4 to 6 cm to obtain a container for bacteria beds or a bag for bacteria beds. If the size of the filter part for the fungus bed bag is 0.1 to 1% of the surface area, the amount of air necessary for the culture is sufficient, and heat generation from the culture medium does not accumulate, and mold generation and decay occur. There is no fear, and there is no fear that the amount of water evaporation will increase and the humidity necessary for fungal culture cannot be maintained.

  In the present invention, the bacteria bed container or the bacteria bed bag is not particularly limited as long as it can hold a medium suitable for the growth physiology of the bacteria. Examples of the material include polyolefins such as polyethylene, polypropylene, and poly-4-methyl-1-pentene, polyesters, polyamides, and the like. Polyolefins and transparent ones are preferable. This is because it is inexpensive and the culture state can be observed from the outside.

  In the present invention, the shape of the fungus bed container or the fungus bed bag is not particularly limited, and examples thereof include an arbitrary shape such as a gusset shape, a stand pouch shape, a flat bag shape, and a bottle shape.

  In the container for a fungus bed or the bag for a fungus bed of the present invention, a medium is placed in the container or bag, and the bacteria are cultured on or in the medium. In this case, since the filter for the fungus bed bag attached to the container or the bag is excellent in gas permeability, air is supplied through the filter, so that the growth rate of the mycelium is high.

  Bacteria cultured in the fungus bed container or fungus bed bag of the present invention are not particularly limited as long as they can be cultivated. For example, shiitake mushrooms, maitake mushrooms, agaricus koji, beech shimeji mushrooms, enoki mushrooms, nameko, mushrooms, oyster mushrooms , Jellyfish, bamboo shoots, chestnut mushrooms, scallops, scallops, mushrooms, oyster mushrooms, mushrooms, aratake, willow matsutake, yamabushitake, matsuouji, beech haritake and the like.

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by these.
The polyolefin resin (C) used in Examples and Comparative Examples polymerizes crystalline polypropylene (A) at the first stage by a continuous polymerization method, and propylene-α-olefin copolymer (B) at the second stage. It was obtained by polymerizing (propylene-ethylene copolymer).
In addition, the measuring method and evaluation method used by the Example and the comparative example are as follows.

(1) Melt flow rate (MFR): Measured according to JIS K 7210 under conditions of a temperature of 230 and a load of 21.18N.

(2) Porosity: The bulk specific gravity is obtained from the filter sample 100 × 100 mm for the fungus bed bag, and the automatic specific gravity manufactured by Toyo Seiki Seisakusho Co., Ltd. is obtained from the non-porous membrane-shaped molded product sample 100 × 100 mm before stretching. The true specific gravity was calculated | required by the total DENSIMETER and DS, and the porosity was calculated | required from the following formula.
Porosity (%) = (1-bulk specific gravity / true specific gravity) × 100

(3) Air permeability resistance (Gurley): an index indicating gas permeability, and time required for 100 ml of air to pass through a B-type Gurley densometer (trade name, manufactured by Tester Sangyo Co., Ltd.) according to JIS P 8117 Was measured.

(4) Pore size: An index indicating the pore size. Based on ASTM F 316, the pore size of the filter for bacterial bed bags was measured using a Perm-Porometer manufactured by PMI, and the average flow pore size was taken as the pore size.

(5) Bacterial contamination: The bacterial contamination of the medium was visually observed and evaluated according to the following criteria.
A: No contamination was observed in all 10 bags.
○: Contamination of some bacteria is observed for one bag. Δ: Contamination of bacteria is observed for each part of 3 bags or less.
X: Contamination of bacteria is remarkable for 4 bags or more

(6) Breeding period: The growing period of Shiitake mushrooms was observed with the naked eye, and the number of days when the entire medium was grown after inoculating the medium with the inoculum was taken as the growing period.

1) Preparation of filter resin composition for fungus bed bag Using polyolefin resin (C) shown in Example 1 of Table 1, tetrakis [methylene-3- (3 ′, 5'-di-t-butyl-4'-hydroxyphenyl) propionate] 0.1% by weight of methane and 0.1% of tris (2,4-di-t-butylphenyl) phosphite as a phosphorus antioxidant. 1% by weight calcium stearate as a neutralizing agent, mixed with a Henschel mixer (trade name), melt-kneaded using a twin-screw extruder (caliber 50 mm), pelletized, and used for bacterial bed bags A resin composition for a filter was obtained.

2) Preparation of filter for fungus bed bag [Film forming process / Creation of unstretched film-shaped product]
Using a 20 mm extruder equipped with a T die with a lip width of 120 mm, the pellet-shaped resin composition was melted at an extrusion temperature of 280 ° C. and a discharge rate of 4 kg / h, and the lip clearance was adjusted to 0.20 mm. The film was further extruded into a film shape and cooled and solidified on a cooling roll at 80 ° C. to prepare a film-shaped molded product having a width of 100 mm and a thickness of 200 μm. When the film-like molded product in a molten state was cooled and solidified, the non-contact surface with the cooling roll was air-cooled with an air knife.

3) [Drawing process / Preparation of filter for fungus bed bag]
The film-shaped product was uniaxially stretched in the machine direction (MD) using a longitudinal uniaxial stretching machine under the conditions of a stretching roll temperature of 23 ° C., a feeding speed of 10 m / min, and a stretching ratio of 3 times. Further, stretching was performed in the transverse direction (TD) while restraining the longitudinal direction under the conditions of a stretching temperature of 23 ° C. and a deformation rate of 200% to obtain a filter for a fungus bed bag. The obtained filter for fungus bed bags had excellent gas permeability and strength. The characteristics evaluation results of the filter for the fungus bed bag are shown in Table 1.

4) Production of container for fungus bed A tubular film having a thickness of 30 μm and a width of 30 cm was formed by a blown film forming method using high density polyethylene having a density of 0.946 g / cm ³ and MFR of 0.04 g / 10 min. Next, using a tubular film, both sides were folded by 5 cm by a gusset type bag making machine to form a polyethylene bag having a length of 45 cm and a finished width of 20 cm. The bottom seal is a boat bottom heat seal with a heat sealer, and when the inside is filled with sawdust of the culture medium, the bottom becomes a square bottom and the bag is made so as to be able to stand by itself stably. As shown in FIG. 1, holes for a diameter of 2.5 cm are perforated at two locations above and below the central portion of the side surface of the bag, and the above-mentioned fungus bed bag cut into 5 cm squares so as to cover the perforated portion. The filter was pressure-bonded with a circular heat sealer having a diameter of 4 cm to obtain a fungus bed bag.

5) Cultivation method In the above-mentioned bag for bag, araogaga waste and bran were mixed at a volume ratio of 10: 1, and 1 kg of a medium adjusted to a moisture content of 62% was filled per bag. Next, after sterilizing at 117 ° C. for 90 minutes in a high-pressure steam sterilizer, the medium was cooled to room temperature. Next, Shiitake fungus was inoculated in a clean room, and the opening of the bag was heat sealed with a heat sealer and sealed. This was cultured in a culture room at a room temperature of 21 ° C., and the culture period and the degree of contamination of bacteria and bacteria in the medium were observed at two locations above and below the medium in the bag. The results are shown in Table 1.

  A filter for a fungus bed bag was obtained according to Example 1 except that the polyolefin resin (C) shown in Example 2 of Table 1 was used. The evaluation results of the characteristics of the filter for fungus bed bags and the bag for fungus beds are shown in Table 1.

  A filter for bacterial bed bags was obtained in the same manner as in Example 1 except that the polyolefin resin (C) shown in Example 3 of Table 1 was used. The evaluation results of the characteristics of the filter for fungus bed bags and the bag for fungus beds are shown in Table 1.

(Comparative Example 1)
Henschel mixer (trade name) of 40% by weight of linear low density polyethylene (FS150A (trade name), manufactured by Tosoh Corporation, density 0.921, MFR 1.0 g / 10 min) and 60% by weight of calcium carbonate having an average particle diameter of 1 μm ), The mixture was melt-kneaded and pelletized using a twin-screw extruder (caliber 50 mm) to obtain a resin composition for a filter for bacterial bed bags. An unstretched film-shaped molded product was prepared according to Example 1, and the film-shaped molded product was then stretched at a stretching roll temperature of 60 ° C., a feeding speed of 10 m / min, and a stretching ratio of 2 times using a longitudinal uniaxial stretching machine. Under the conditions, uniaxial stretching was performed in the machine direction (MD). Furthermore, 1.5 times of stretching was performed in the transverse direction (TD) while constraining the longitudinal direction under the conditions of a stretching temperature of 80 ° C. and a deformation rate of 200% to obtain a filter for a fungus bed bag. The obtained mycelia bag had a low resistance to air permeability, and good hyphal growth could not be obtained. The occurrence of blue mold was also observed. The characteristics of the filter for fungus bed bags and the bag for fungus beds are shown in Table 1.

(Comparative Example 2)
Using the polyolefin resin (C) shown in Comparative Example 2 in Table 1, a filter for a fungus bed bag was prepared according to Example 1. In Comparative Example 2, when the film was stretched in the horizontal direction, the film was cut at a draw ratio of less than 2 and the stretchability was inferior, and the characteristics as a filter for a fungus bed bag were not obtained.

(Comparative Example 3)
Instead of the polyolefin resin (C), 50% by weight of a propylene homopolymer (crystalline polypropylene having an MFR of 2.5 g / 10 min) and an ethylene homopolymer (MFR of 0.75 g / min (temperature 190 ° C., load 21. 18N) HDPE) Except for using 50% by weight, a filter for a fungus bed bag was prepared according to Example 1. However, when stretched in the transverse direction, the stretch breakage occurred at a stretch ratio of less than 1.5 times. It was inferior to stretchability.

  In the film forming step, the same procedure as in Example 3 was performed except that the draft ratio was 3.6 and the thickness of the film-shaped molded product was 200 μm. Table 2 shows the evaluation results of the characteristics of the filter for fungus bed bags and the bag for fungus beds.

  In the film forming step, the same procedure as in Example 3 was performed except that the draft ratio was 7.2 and the thickness of the film-shaped molded product was 200 μm. Table 2 shows the evaluation results of the characteristics of the filter for fungus bed bags and the bag for fungus beds.

  The stretching process was performed in the same manner as in Example 3 except that the transverse stretching temperature was 80 ° C. Table 2 shows the evaluation results of the characteristics of the filter for fungus bed bags and the bag for fungus beds.

(Comparative Example 4)
In the film forming step, the same procedure as in Example 3 was performed except that the draft ratio was set to 12 and the thickness of the film-shaped molded product was set to 200 μm. The obtained fungus bed bag had a high resistance to air permeability, and good hyphal growth could not be obtained. Table 2 shows the characteristics of the filter for fungus bed bag and the bag for fungus bed bag.

  A filter for a fungus bed bag was obtained according to Example 1 except that the polyolefin resin (C) shown in Example 7 of Table 3 was used. Table 3 shows the evaluation results of the characteristics of the filter for the fungus bed bag and the fungus bed bag.

  A filter for a fungus bed bag was obtained according to Example 1 except that the polyolefin resin (C) shown in Example 8 of Table 3 was used. Table 3 shows the evaluation results of the characteristics of the filter for the fungus bed bag and the fungus bed bag.

  In the film forming step, the same procedure as in Example 7 was performed except that the draft ratio was 1.2 and the thickness of the film-shaped molded product was 200 μm. Table 3 shows the evaluation results of the characteristics of the filter for the fungus bed bag and the fungus bed bag.

  In the film forming step, the same procedure as in Example 7 was performed except that the draft ratio was 7.2 and the thickness of the film-shaped molded product was 200 μm. Table 3 shows the evaluation results of the characteristics of the filter for the fungus bed bag and the fungus bed bag.

(Comparative Example 5)
In the film forming step, the same procedure as in Example 7 was performed except that the draft ratio was set to 12 and the thickness of the film-shaped molded product was set to 200 μm. Table 3 shows the evaluation results of the characteristics of the filter for the fungus bed bag and the fungus bed bag. The obtained fungus bed bag had a high resistance to air permeability, and good hyphal growth could not be obtained. Table 3 shows the characteristics of the filter for fungus bed bags and the bag for fungus beds.

(Comparative Example 6)
As a filter for a fungus bed bag, a fungus was used in the same manner as in Example 1 using a porous polypropylene film (trade name: JURAGARD manufactured by Celanese, USA) having a pore size of 0.1 μm, an air permeability of 600 seconds / 100 ml, and an air gap ratio of 38%. Floor bags were made and evaluated. The obtained fungus bed bag had a high resistance to air permeability, and the growth period of the fungus was as long as 110 days. Thus, good hyphal growth could not be obtained.

(Comparative Example 7)
Using a non-woven fabric (trade name, manufactured by Tyvek Deyupon Co., Ltd.) having a basis weight of 74.6 g / m ² , a pore diameter of 2.4 μm, and a thickness of 210 μm as a filter for the fungus bed bag, evaluated. The resulting fungus bed bag had low resistance to air permeability, and a good hypha growth environment was in place, but contamination of bacteria such as blue mold was observed in 7 out of 10 bags, and generation of blue mold was extremely good. Growth was not obtained.

(Table 1)

(Table 2)

(Table 3)

  The filter for the fungus bed bag of the present invention is not particularly limited as long as the fungus can be used in fungus bed cultivation. For example, fungus beds such as shiitake mushroom, maitake mushroom, agaricus koji, bunashimeji, enoki mushroom, nameko, mushroom, oyster mushroom, and jellyfish It is suitably used for a filter for bacteria beds such as a container for bacteria and a bag for bacteria beds.

An example of the bag for fungus beds of the present invention is shown.

Explanation of symbols

1: Bacteria bed bag 2: Opening for ventilation 3: Bacteria bed bag filter 4: Junction 5: Medium (Naraogaga waste and bran)

Claims (15)

A resin composition containing a polyolefin resin (C) composed of crystalline polypropylene (A) and a propylene-α-olefin copolymer (B) dispersed in the crystalline polypropylene (A) is melted and kneaded to form a film. A filter formed by forming a film-like melt, forming the film-like melt into a film-like molding, and then stretching the film-like molding in at least one direction, wherein the polyolefin resin (C) is crystalline. Polypropylene (A) is composed of 30 to 90% by weight and propylene-α-olefin copolymer (B) is composed of 10 to 70% by weight, and polyolefin resin (C) produces crystalline polypropylene (A) in the first stage. And a draft obtained when a film-like melt is formed into a film-like molded article obtained by a multi-stage polymerization method including a step of continuously producing the propylene-α-olefin copolymer (B) in the second stage. The ratio is in the range of 1 to 10,
A filter for a fungus bag having pores communicating with the copolymer (B) region. The melt flow rate ratio MFR _PP / MFR _RC of the melt flow rate MFR _PP of the crystalline polypropylene (A) and the melt flow rate MFR _RC of the propylene-α-olefin copolymer (B) is 0.1 to 10. The filter for a fungus bed bag according to claim 1, The filter for fungus bed bags according to claim 2, wherein the melt flow rate ratio MFR _PP / MFR _RC is 0.2 to 5. The filter for a fungus bed bag according to any one of claims 1 to 3 , wherein a draft ratio when the film-shaped melt is formed into a film-shaped molded product is in a range of 1 to 3. The polyolefin resin (C) is composed of 40 to 70% by weight of a crystalline polypropylene (A) and 30 to 60% by weight of a polypropylene-α-olefin copolymer (B). The filter for fungus bed bags according to 1. The filter for bacterial bed bags according to any one of claims 1 to 5, wherein the propylene content of the propylene-α-olefin copolymer (B) is 30 to 80% by weight. The filter for bacterial bed bags according to any one of claims 1 to 5, wherein the propylene content of the propylene-α-olefin copolymer (B) is 40 to 70% by weight. The filter for a fungus bed bag according to any one of Claims 1 to 7, wherein the air permeability resistance (Gurley) is 10 to 300 seconds / 100 ml, and the pore diameter measured by the ASTM F316 method is 0.1 to 1 µm. A resin composition containing a polyolefin resin (C) composed of crystalline polypropylene (A) and a propylene-α-olefin copolymer (B) dispersed in the crystalline polypropylene (A) is melted and kneaded to form a film. A filter formed by forming a film-like melt, forming the film-like melt into a film-like molding, and then stretching the film-like molding in at least one direction, wherein the polyolefin resin (C) is crystalline. It consists of 30 to 70% by weight of polypropylene (A) and 30 to 70% by weight of propylene-α-olefin copolymer (B) to produce crystalline polypropylene (A) in the first stage, and continuously in two stages. It is obtained by a multistage polymerization method including a step of producing a propylene-α-olefin copolymer (B), and a draft ratio when forming a film-like melt into a film-like molding is in the range of 1 to 10. , Filters for mushroom bed bag having pores communicating with the polymer (B) region. Melt flow rate MFR of crystalline polypropylene (A) _PP Flow rate MFR of propylene-α-olefin copolymer (B) _RC Melt flow rate ratio MFR _PP / MFR _RC 10. The filter for a fungus bed bag according to claim 9, wherein is more than 10 and 1,000 or less. The filter for a fungus bed bag according to claim 9 or 10, wherein a draft ratio when the film-shaped melt is formed into a film-shaped molded product is in the range of 1 to 5. The filter for fungus bed bags according to any one of claims 9 to 11, wherein the propylene content of the propylene-α-olefin copolymer (B) is 30 to 80% by weight. The filter for a fungus bed bag according to any one of claims 9 to 11, wherein the propylene content of the propylene-α-olefin copolymer (B) is 40 to 70 wt%. The filter for a fungus bed bag according to any one of claims 9 to 13, wherein the air permeability resistance (Gurley) is 50 to 500 seconds / 100 ml, and the pore diameter measured by ASTM F316 method is 0.5 to 1 µm. A container for fungus beds or a bag for fungus beds using the filter for fungus bed bags according to any one of claims 1 to 14.

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