JP4889285B2 - Manufacturing method of parts for chuck in biodegradable chuck bag. - Google Patents

Description

  The present invention relates to a method for efficiently manufacturing a chuck component with high dimensional accuracy in a biodegradable chuck bag using a biodegradable resin as a chuck.

A packaging bag provided with a chuck portion (also called a zipper, hereinafter referred to as a chuck portion) that can be repeatedly opened and closed at the mouth portion of the bag is a food, clothing, medicine, miscellaneous goods and many other Used in the packaging field. The packaging bag (chuck bag) provided with these chuck parts is provided with chuck parts consisting of convex members and concave parts in the chuck part, and can be opened and closed repeatedly by fitting the convex members and concave parts. It has become. Polyolefin resins such as polyethylene, polypropylene, and ethylene vinyl acetate copolymers are widely used as materials for these chuck bags.
Chuck bags using polyolefin resin are discarded as waste after use and are incinerated or landfilled. However, there is a problem that the amount of generated heat during combustion is large and the landfill is insufficient because it does not decompose over a long period of time. In recent years, research on a chuck bag using a biodegradable resin that has a low combustion heat amount and decomposes quickly after landfilling has been conducted due to increasing interest in environmental problems.

Patent Document 1 describes a biodegradable bag with a chuck in which a film made of a polylactic acid polymer and an aliphatic polyester is provided with a chuck made of an aliphatic polyester. This biodegradable bag with a zipper is transparent, and it is described that the chuck does not come off the bag even when the chuck is repeatedly opened and closed. On the other hand, the important point of the function of the chuck bag is that the chuck portion can be easily opened and closed, and the contents are not spilled when the chuck portion is closed. For this reason, strict dimensional accuracy is required for manufacturing the convex member and the concave member of the chuck component. If the opening of the concave member is small with respect to the convex member, an excessive force is required for opening and closing, and the chuck portion may not fit in some cases. On the other hand, if the opening of the concave material is large relative to the convex member, opening and closing is easy, but repeated opening and closing will reduce the strength of the chuck part, and if the bag is tilted with the contents in place, the contents will The chuck may open and the contents may spill.
In the case of a polyolefin chuck, it is relatively easy to manufacture a chuck component with high dimensional accuracy. However, if a biodegradable resin is used, a chuck component with high dimensional accuracy cannot be produced or even 500 m. It may be difficult to stably produce a chuck component having a high dimensional accuracy continuously over a distance of 2000 m.
JP 10-146936 A

  An object of the present invention is to provide a manufacturing method of a chuck part with high dimensional accuracy in a bag with a biodegradable chuck using a biodegradable resin for a chuck part, that is, the chuck part can be easily opened and closed repeatedly. It is an object of the present invention to provide a method for stably producing a biodegradable bag with a chuck having excellent durability in which the strength of the chuck portion does not greatly decrease even when the chuck portion is opened and closed.

In the biodegradable chuck bag using the biodegradable resin for the chuck portion, the present inventors have a phenomenon that the shape stability of the chuck component is lowered when the chuck component is solidified during the manufacture of the chuck portion. Is that it is a cause of the reduction in the dimensional accuracy of the chuck parts, after melting a specific resin composition with an extruder, extruded from a die having an opening for forming a convex member, a concave material, It discovered that the said subject was solved by cooling at a cooling rate of 40 to 60 degree-C / sec, and came to make this invention.
That is, the present invention is as follows.
(1) It has a chuck part for opening and closing the bag at the mouth part of the bag formed of a film containing aliphatic polyester as a main component, and the chuck part is composed of a convex member and a concave material that can be fitted to each other. A method for manufacturing a chuck part in a biodegradable chuck bag made of a chuck part, wherein the value of bending elastic modulus is 150 MPa to 300 MPa , and the value of 70 ° C. storage elastic modulus is 10 ⁵ to 10 ⁷ Pa . there, melting a resin composition mainly composed of an aliphatic polyester resin, after each is formed from a die having an opening for components chuck formed by extruding convex member and the chuck parts comprising a recessed member, the speed A method for producing a chuck part of a biodegradable chuck bag comprising cooling at 40 ° C./second to 60 ° C./second.
(2) The chuck part of the biodegradable chuck bag according to (1) , wherein the film forming the bag and the aliphatic polyester as the main component of the chuck portion are polylactic acid-based resins. Method.
(3) The biodegradable chuck according to (1) or (2), further comprising 0.05 to 10 parts by mass of a crystallization nucleating agent with respect to 100 parts by mass of the resin composition constituting the chuck part A method of manufacturing a bag chuck part.

  According to the present invention, it is possible to manufacture a chuck bag chuck component having high dimensional accuracy and high chuck strength. Therefore, it is easy to open and close the chuck portion, and it is possible to obtain a chuck bag provided with a highly durable chuck portion that does not greatly reduce the chuck strength even if the chuck portion is repeatedly opened and closed.

The present invention will be described in detail focusing on preferred embodiments.
The biodegradable chuck bag of the present invention comprises at least a biodegradable film and a biodegradable chuck portion. The chuck portion may include a lead that makes it easier to pinch the opening, an opening / closing device (slider) that makes opening and closing of the chuck easier, in addition to the chuck component made of a convex member and a concave member.
When manufacturing a biodegradable chuck bag based on the present invention, for example, a biodegradable film and a biodegradable chuck component constituting the bag are simultaneously extruded from a die, and at that time, a chuck comprising a convex member and a concave member Adjusting the positional relationship so that the parts are fitted to each other and fusing the chuck parts on the film, manufacturing the biodegradable film and the biodegradable chuck parts individually, For example, a method may be used in which the positional relationship is adjusted so that the chuck parts made of members are fitted to each other, and the chuck parts are bonded onto the film. The latter method is preferable in that a zipper bag having a design property can be obtained because the chuck can be bonded after printing on the film.

Hereinafter, a method of individually manufacturing and bonding the film and the chuck portion will be described.
The film constituting the biodegradable chuck bag of the present invention may be a single-layer film or a multilayer film, but a multilayer film is preferred from the viewpoint of easily satisfying the flexibility and sealing strength required for the chuck bag. .
Resin containing 50 mass% or more of aliphatic polyester is used for the film which comprises the main body of the biodegradable chuck bag of this invention. Examples of the aliphatic polyester include a polylactic acid resin, a polycondensation product of an aliphatic diol and an aliphatic dicarboxylic acid. Examples of the polylactic acid-based resin include polylactic acid, a copolymer of lactic acid and other hydroxycarboxylic acid, and the like. Examples of hydroxycarboxylic acids include glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 3-hydroxyvaleric acid, 4-hydroxyvaleric acid, 6-hydroxycaproic acid and the like.

  In the polycondensation product of the aliphatic diol and the aliphatic dicarboxylic acid used in the present invention, urethane bonds, amide bonds, ether bonds, etc. are introduced in the molecule within a range that does not substantially affect biodegradability. Also good. Examples of the aliphatic diol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, , 3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol and the like. Examples of aliphatic dicarboxylic acids include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, suberic acid, sebacic acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, Examples include 1,3-cyclohexanedicarboxylic acid and diglycolic acid.

Other resins may be used for the film constituting the biodegradable chuck bag of the present invention as long as the biodegradability is not inhibited. As other resins, for example, it is preferable to use aliphatic-aromatic polyester in an amount of 50% by mass or less, more preferably 30% by mass or less, based on the film-constituting resin, since the impact resistance of the film and bag is improved. Other examples include natural polymers, cellulose esters, and ethylene-vinyl alcohol copolymers.
Furthermore, additives such as a plasticizer, a lubricant, an antistatic agent, an ultraviolet absorber, an antioxidant and a flame retardant may be used for the film constituting the biodegradable chuck bag of the present invention.
Examples of suitable plasticizers include aliphatic alcohols, alicyclic alcohols, polyhydric alcohols thereof, and polycondensates thereof; at least one alcohol component selected from these, aliphatic fatty acids, aliphatic polyhydric acids. Esters with at least one acid component selected from monovalent carboxylic acids and aromatic polycarboxylic acids; Natural fatty acid esters; Esters of aliphatic hydroxycarboxylic acids and alcohols; Esters of aliphatic hydroxycarboxylic acids and aliphatic fatty acids , Esters of aliphatic hydroxycarboxylic acids with alcohols and aliphatic fatty acids, and modified products of these esters; polyoxyethylene alkyl ethers and esters thereof; oligomers of aliphatic polyesters, cyclic dimers and monomers; Low weight consisting of mineral oil, liquid paraffin and saturated hydrocarbon compounds Thing, and the like. These plasticizers may use one kind or a mixture of one or more kinds. The addition amount of the plasticizer is preferably in the range of 0.5 to 30 parts by mass with respect to 100 parts by mass of the resin constituting the film.

Examples of suitable lubricants include talc, kaolin, calcium carbonate, magnesium carbonate, bentonite, mica, graphite, magnesium hydroxide, aluminum hydroxide, antimony trioxide, barium sulfate, zinc borate, zinc stearate, magnesium stearate. Etc. The addition amount of the lubricant is adjusted in the range of 0.05 to 3 parts by mass with respect to 100 parts by mass of the resin constituting the film.
As the additives such as ultraviolet absorbers, antioxidants, and flame retardants, those equivalent to those used for polyester films such as known polyethylene terephthalate are suitable.
The film can be produced by a known method. For example, after melt-kneading raw materials such as aliphatic polyester and additives in an extruder, the film extruded from a T-die, I-die, round die, etc. is cooled and solidified by a cast roll, water, or compressed air to form an unstretched film. obtain. Thereafter, a stretched film stretched by a stretching method such as a roll method, a tenter method, or a tubular method may be used. The film thickness is preferably 15 μm to 100 μm, more preferably 20 μm to 70 μm, which is appropriate for the chuck bag.

For the chuck portion constituting the biodegradable chuck bag of the present invention, 50% or more of aliphatic polyester is used. The resin composition used for the chuck portion and the resin composition used for the film may be the same or different. Since heat bonding such as heat sealing is generally used when bonding the film and the chuck part, it is high when 50% or more of the resin composition constituting the film and the resin composition constituting the chuck part are the same resin composition. Since adhesiveness is obtained, it is preferable.
In order to satisfy the flexibility required for the chuck, the flexural modulus of the resin composition constituting the chuck component provided in the chuck portion must be 150 MPa to 300 MPa. Further it may turn smaller reduction of the chuck strength upon repeated opening and closing the chuck when in the range of 150～300MPa. If the flexural modulus is lower than 150 MPa, the chuck strength is insufficient, and the contents may spill when the bag is tilted. When the flexural modulus is higher than 400 MPa, a large force is required to open the bag, and the chuck component may peel from the bag when the bag is opened. By adding an appropriate amount of plasticizer to the biodegradable resin used for the chuck component, the bending elastic modulus of the resin constituting the chuck component can be set to 150 MPa to 400 MPa. As the plasticizer, those described in the example of the plasticizer used in the film constituting the biodegradable chuck bag of the present invention can be used. The amount of the plasticizer added is generally adjusted in the range of 0.5 to 30 parts by mass with respect to 100 parts by mass of the resin constituting the chuck component.

Range of storage elastic modulus (G') at 70 ° C. of the resin composition constituting the component chucks is ¹⁰ 5 ^~10 7 Pa. When the storage elastic modulus at 70 ° C. is lower than 10 ⁴ Pa, solidification at the time of cooling after extruding the chuck component is slow, and the shape stability of the chuck component described later may be easily lowered. If the storage elastic modulus at 70 ° C. is higher than 10 ⁹ Pa, the load on the extruder at the time of manufacturing the chuck portion becomes high, and the production rate may not be increased.
A crystallization nucleating agent may be used in the chuck portion constituting the biodegradable chuck bag of the present invention. When a crystallization nucleating agent is used, solidification at the time of cooling after extruding the chuck part is accelerated, and the storage elastic modulus at 70 ° C. can be increased. Examples of suitable crystallization nucleating agents include talc, kaolin, calcium carbonate, magnesium carbonate, bentonite, mica, graphite, magnesium hydroxide, aluminum hydroxide, antimony trioxide, barium sulfate, zinc borate, zinc stearate, Examples include magnesium stearate. The addition amount of the crystallization nucleating agent is generally adjusted in the range of 0.05 to 10 parts by mass with respect to 100 parts by mass of the resin constituting the chuck part.

Next, a method for manufacturing the chuck portion will be described. As shown in FIG. 1, the chuck part is provided with a chuck component including a concave member 12 and a convex member 11 on a film 13 constituting a bag body, and a lead, a slider, and the like are provided as necessary. In the manufacture of the chuck component, the resin composition constituting the chuck component is melt-kneaded in an extruder, and then extruded from a die having an opening for forming a concave member and a convex member. As shown in FIG. 2, it is preferable to provide the chuck base 14 on the film 13 in the shape of the concave material and the convex member, because the chuck part and the bag body can be easily bonded.
When the lead is provided in the chuck portion, it is preferable that the resin composition constituting the lead is made the same composition as the chuck component and is extruded from a die having an opening for lead formation at the same time as the chuck component.

When the slider is provided, the resin mentioned as an example of the aliphatic polyester suitable for the film constituting the biodegradable chuck bag is injection molded into the shape of the slider, and the slider and chuck are used when making the bag. After the parts are integrated, a zipper bag is made.
As shown in FIG. 3, the chuck component and the film (when the lead is provided, the chuck component and the lead and the film) are bonded to the film before the resin of the extruded chuck component is solidified. Examples include a method of extruding the chucked tapes 15 and 16 having an enlarged chuck base and cooling and solidifying them, and then bonding the film and the tape with chucks in a later step.

  In the former manufacturing method, while a film is fed at a constant speed, a predetermined amount of a molten resin composition constituting a chuck component is extruded onto the film by the above-described method. It may be heat-bonded to the film before the resin composition is solidified. Next, it is cooled with water or the like so that the molten resin composition is solidified to obtain a film with a chuck. Thereafter, the film is dried if necessary, and the film with a chuck is wound up in a roll by a winder. The obtained film with a chuck is made into a bag using a bag making machine having functions such as heat sealing and fusing sealing to obtain a biodegradable chuck bag. As the bag making machine, a bag making machine equivalent to that used for manufacturing polyolefin chuck bags can be used.

In the latter manufacturing method, when extruding a chuck component composed of the convex member 11 and the concave member 12, the resin composition is extruded into the shape of the chucked tapes 16 and 17 shown in FIG. Cool with water. Next, the tape with chuck is dried as necessary, and then wound with a winder. Thereafter, the film and the tapes with chucks 15 and 16 are bonded by means of heat sealing or the like. Even with the bonding method using an adhesive. The film and the tape with chuck are bonded and bag-formed using a bag-making machine equipped with functions such as heat sealing and fusing sealing, which can perform the bonding process and the bag manufacturing process of the chuck bag. can get.
Since the chuck part immediately after being extruded is in a molten state, deformation is likely to occur before cooling and solidification. In particular, as shown in FIG. 4, the resin composition extruded from a deformed die that forms the concave member and the convex member may collapse the convex member 17 and the concave member 18, thereby reducing the shape stability. The decrease in the dimensional accuracy of chuck parts made of biodegradable resin is mainly due to the decrease in shape stability. If you try to fit these concave and convex members with reduced shape stability, if you can not fit at all, you can fit, but the chuck strength is too strong, and excessive force is required to open the chuck part The chuck strength is weak, and the chuck strength may be greatly reduced by repeatedly opening and closing the chuck portion.

When manufacturing chuck parts with a length of 500 m to 2000 m, high dimensional accuracy of the chuck parts is required, but it is possible to form a part of a chuck part with a length of 500 m to 2000 m. If a chuck component with reduced stability is included, the productivity is significantly reduced. Aliphatic polyester resins with biodegradability are characterized by the time required to solidify from the melted state compared to polyolefin resins, and the problem that shape stability decreases as cooling takes more time is more likely to appear. The present inventors have discovered.
In order to solve this problem, the resin composition constituting the chuck component of the present invention is 40 ° C./second to 60 ° C./second after being extruded from a die having an opening for forming a concave member and a convex member. It is necessary to cool at. More preferably, it is 45 ° C./second to 60 ° C./second. When the cooling rate is lower than 40 ° C./second, the shape stability is lowered, and when it is higher than 60 ° C./second, there is no problem in the shape stability, but the cooling equipment becomes excessive and is not economical. In order to set the cooling rate to 40 ° C./second or less, it is preferable to cool the resin composition extruded from the die with a low-temperature fluid or a low-temperature metal roll. A preferred fluid is water. The combination of cooling with a fluid such as water and cooling with a metal roll is more preferable because it has the effect of increasing the cooling rate.

Specific cooling means include a method in which a resin composition extruded from a die is passed through a cooling tank for storing water, a method in which water is injected into a resin composition extruded from a die, and a resin extruded from a die. Examples include a method of cooling the composition in contact with a rotating metal roll. The resin composition extruded from the die is preferably in contact with a cooling medium such as water, a cooling metal roll, or the like within 0.5 seconds, more preferably within 0.3 seconds. The cooling medium temperature such as water and the surface temperature of the metal roll are preferably 40 ° C. or lower, more preferably 25 ° C. or lower.
The cooling rate of the resin composition constituting the chuck component of the present invention can be calculated by the following formula.
(T1-T2) / 3 Unit: ° C./second Here, T1 is the surface temperature of the resin composition immediately after being extruded from the die. Unit: ° C.
T2 is extruded from the die and the surface temperature of the resin composition after 3 seconds. Unit: ° C

EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to these Examples.
The measuring method used in the present invention is as follows.
(1) Flexural modulus It conforms to JISK7171.
The chuck parts are peeled off from the chuck bag, press-molded at 20 ° C. for 2 minutes with a hot press at 190 ° C., and immediately cooled in water at 20 ° C. immediately after forming to form a sheet having a thickness of 2 mm. A test piece is cut out from the obtained sheet into a width of 10 mm and a length of 40 mm, and the flexural modulus is measured according to the measurement method of JIS K7171 (test speed: 10 mm / min).

(2) Storage elastic modulus Conforms to JISK7244-10.
A 2 mm-thick sheet used for measuring the flexural modulus was used as a measurement sample. For the measurement, a rheometer (ARES) manufactured by Rheometrics (currently TA Instruments) is used. For the measurement, an 8 mm diameter parallel plate was used, the frequency was 1.0 rad / sec, the measurement start temperature was equal to or higher than the melting point (180 ° C. in the case of the example resin), and the measurement end temperature was 50 ° C. Strain is performed at 0.01%.
(3) Surface temperature of resin composition A non-contact type radiation thermometer (manufactured by Horiba: IT-550S) is used for measuring the surface temperature of the resin composition. The measurement points are the surface temperature (T1) of the resin composition (part for concave material chuck) immediately after being extruded from the die having an opening for forming the concave material, and the resin after 3 seconds from the extrusion. The surface temperature (T2) of the composition (part for concave material chuck) is measured.

(4) Chuck strength Two test pieces are cut out from the chuck bag in a size of 15 mm × 100 mm so that the concave material and the chuck component of the convex member are included in the direction perpendicular to the long side (the upper part of the test piece). The recessed part and the chuck part for the convex member are located at a position 30 mm from the top). Next, each test piece is set on the gripping tool of a tensile tester (Shimadzu Autograph AG-IS) with two pieces of 70mm film at the bottom of the chuck part fitted into the concave and convex parts. Then, the maximum value of the tensile stress is measured according to JISK7127 (the distance between grips is 100 mm, the tensile test speed is 50 mm / min), and the values obtained by five measurements are averaged to obtain the chuck strength.

(5) Dimensional accuracy of parts for chuck A chuck bag having a length of 500 m or more in terms of film length is manufactured, and the chuck bag is sampled at 10 points from the point corresponding to the 50 m interval in film length. The chuck strength is measured by the method (4), the standard deviation of the chuck strength at 10 points is obtained, and the determination is made according to the following criteria.
○: Quasi-deviation is less than 3 △: Standard deviation is 3 or more and less than 5 ×: Standard deviation is 5 or more

(6) Durability of the chuck bag Of the ten chuck bags measured in (5), the opening / closing operation is repeated 100 times for the five chuck bags whose chuck strength is close to the average value. Thereafter, the chuck strength is measured again, and the change rate of the chuck strength is calculated for each of the five points according to the following equation. An average value obtained by averaging the change rates of the chuck strength at five points is determined according to the following criteria.
Chuck strength change rate = (initial chuck strength−chuck strength after opening / closing 100 times) / initial chuck strength × 100 (%)
◎ Change rate of chuck strength is less than 5% ○ Change rate of chuck strength is 5% or more and less than 10% △ Change rate of chuck strength is 10% or more

[Example 1]
Film (A)
Polylactic acid (PLA) (manufactured by NatureWorks, NatureWorks (registered trademark) 4032D) was melted with a twin screw extruder having a screw diameter of 40 mm, and a plasticizer DACG (manufactured by Riken Vitamin Co., PL-019) was added to 100 parts by weight of the resin. (Product Name) was injected into the extruder at a rate of 20 parts by weight using an injection pump and mixed to obtain a resin composition. Thereafter, the resin composition is extruded from a T-die having a slit of 340 mm × 1.0 mm, cooled by a cast roll adjusted to 20 ° C., and then wound by a winder, and then unstretched film having a width of 30 cm, a length of 500 m, and a thickness of 50 μm. Got.
Chuck (B)
A plasticizer DACG (PL made by Riken Vitamin Co., Ltd.) is added to 100 parts by weight of polybutylene succinate (PBS) (Showa Polymer Co., Ltd., Bionore (registered trademark) # 1001) and PBS resin with a single screw extruder having a screw diameter of 20 mm. -19) was mixed in advance at a ratio of 1.5 parts by weight and 3 parts by weight of crystallization nucleating agent talc (manufactured by Matsumura Sangyo Co., Ltd., High Filler (registered trademark) # 5000PJ) to 100 parts by weight of PBS resin. After melt-kneading the product, the product was extruded from a die having a concave member and a convex member-shaped opening. The surface temperature of the resin at this time was 170 ° C.

Subsequently, the chuck (extruded resin composition) of each of the concave material and the convex member is heated at a position 30 mm from both ends of the film on the film (A) wound in a roll shape. After being bonded and cooled by a metal roll adjusted to 20 ° C. and water jet at a water temperature of 20 ° C., the adhering water was removed and wound up by a winder at a constant speed of 15 m / min. The time required for the resin composition extruded from the die to be cooled with cooling water was 0.3 seconds. At this time, the cooling rate of the resin composition (chuck B) was 45 ° C./second.
Ten sheets of the film with a chuck thus obtained are cut into a size of 30 cm in width and 20 cm in length at intervals of 50 m, the film is folded in half and the concave material and the convex member are fitted, and then the chuck and the vertical portion are separated by 2 A chuck bag was obtained by heat sealing at 110 ° C. for 4 seconds.
The obtained chuck bag was evaluated for bending elastic modulus, storage elastic modulus, chuck strength, dimensional accuracy of chuck parts, and durability of the chuck bag. The results are shown in Table 1.

[Example 2]
Film (A)
Polylactic acid (PLA) (manufactured by NatureWorks, NatureWorks (registered trademark) 4032D) 70 wt%, polybutylene adipate terephthalate (PBAT) (manufactured by BASF, Ecoflex FBX7011 (product) Name)) 30% by weight, polylactic acid (PLA) (manufactured by NatureWorks, NatureWorks (registered trademark) 4032D) as the resin composition of the inner layer (second layer), and plasticizer DACG (RIKEN vitamins) with respect to 100 parts by weight of the resin Each resin composition was melt-kneaded with two twin-screw extruders having a screw diameter of 35 mm, with 20 parts by weight of PL-019 (trade name) manufactured by the company.
Thereafter, the resin composition was extruded from a three-layer T die (opening shape width 340 mm thickness 1 mm) so that the layer ratio of surface layer / inner layer / surface layer was 1/4/1, and the temperature was adjusted to 20 ° C. The film was cooled with a cast roll and then wound with a winder to obtain an unstretched film having a width of 30 cm, a length of 500 m and a thickness of 50 μm.
A chuck bag was obtained in the same manner as in Example 1 except that the above film (A) was used, and evaluated. The results are shown in Table 1.

[Example 3]
A film (A) was obtained in the same manner as in Example 2.
Chuck (B)
60% by weight of polylactic acid (PLA) (manufactured by NatureWorks, NatureWorks (registered trademark) 4032D), polybutylene succinate (PBS) (manufactured by Showa Polymer Co., Ltd., Bionor (registered trademark)) with a single screw extruder having a screw diameter of 20 mm # 1001) A resin composition premixed at a ratio of 3 parts by weight of crystallization nucleating agent talc (manufactured by Matsumura Sangyo Co., Ltd. High Filler (registered trademark) # 5000PJ) with respect to 40% by weight and 100 parts by weight of the mixed resin was melt-kneaded. Thereafter, the plasticizer DACG (manufactured by Riken Vitamin Co., Ltd., PL-019 (trade name)) is press-fitted into the extruder using an injection pump and mixed so that the resin is 100 parts by weight. A resin composition was obtained.

Thereafter, the resin composition was extruded from a die having a concave member and a convex member-shaped opening. The surface temperature of the resin at this time was 170 ° C. Subsequently, the chuck (extruded resin composition) of each of the concave material and the convex member is heated to a position 30 mm from both ends of the film (A) wound in a roll shape continuously from the feeding machine. After being bonded and cooled by a metal roll adjusted to 20 ° C. and water jet at a water temperature of 20 ° C., the adhered water was removed and wound up by a winder at a constant speed of 15 m / min. The time required for the resin composition extruded from the die to be cooled with cooling water was 0.3 seconds. The cooling rate of the resin composition (chuck B) at this time was 45 ° C./second.
The thus obtained film with a chuck was evaluated by obtaining a chuck bag in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 1]
A film (A) was obtained in the same manner as in Example 1.
Chuck (B)
After melt kneading polybutylene succinate adipate (PBSA) (manufactured by Showa Polymer Co., Ltd., Bionore (registered trademark) # 3001) with a single screw extruder having a screw diameter of 20 mm, it has a concave material and a convex member-shaped opening. Extruded from die. The surface temperature of the resin at this time was 170 ° C. Subsequently, the chuck (extruded resin composition) of each of the concave material and the convex member is heated at a position 30 mm from both ends of the film on the film (A) wound in a roll shape. After being bonded and cooled by a metal roll adjusted to 20 ° C. and water jet at a water temperature of 20 ° C., the adhered water was removed and wound up by a winder at a constant speed of 10 m / min. The time required for the resin composition extruded from the die to be cooled with cooling water was 0.6 seconds. At this time, the cooling rate of the resin composition (chuck B) was 37 ° C./second.
The thus obtained film with a chuck was evaluated by obtaining a chuck bag in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 2]
A film (A) was obtained in the same manner as in Example 1.
Chuck (B)
60% by weight of polylactic acid (PLA) (manufactured by NatureWorks, NatureWorks (registered trademark) 4032D), polybutylene succinate (PBS) (manufactured by Showa Polymer Co., Ltd., Bionor (registered trademark)) with a single screw extruder having a screw diameter of 20 mm # 1001) 40% by weight of the mixed resin was melted and extruded from a die having a concave member and a convex member-shaped opening. The surface temperature of the resin at this time was 170 ° C.
Subsequently, the chuck (extruded resin composition) of each of the concave material and the convex member is heated at a position 30 mm from both ends of the film on the film (A) wound in a roll shape. After being bonded and cooled by a metal roll adjusted to a temperature of 20 ° C. and water jet at a water temperature of 20 ° C., the adhered water was removed and wound up by a winder at a constant speed of 15 m / min. The time required for the resin composition extruded from the die to be cooled with cooling water was 0.3 seconds. At this time, the cooling rate of the resin composition (chuck B) was 45 ° C./second.
The thus obtained film with a chuck was evaluated by obtaining a chuck bag in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 3]
A film (A) was obtained in the same manner as in Example 1 except that the resin composition was 100 parts by weight of low-density polyethylene: LDPE (Suntech (registered trademark) F1920 manufactured by Asahi Kasei Chemical Co., Ltd.).
Chuck (B)
60 parts by weight of low-density polyethylene (LDPE) (manufactured by Asahi Kasei Chemical Co., Ltd., Suntec (registered trademark) M6520.4) and ethylene vinyl acetate (EVA) (manufactured by Sumitomo Chemical Co., Ltd., Evertate (registered trademark) D1012) 40 weights A film with a chuck was prepared in the same manner as in Comparative Example 1 except that the film was a part. At this time, the time required for the resin composition extruded from the die to be cooled with cooling water was 0.6 seconds. The cooling rate of the resin composition (chuck B) at this time was 37 ° C./second.
The thus obtained film with a chuck was evaluated by obtaining a chuck bag in the same manner as in Example 1. The results are shown in Table 1.

  The present invention is suitably used in food, clothing, pharmaceuticals, sundries and many other packaging fields. In addition, since it has biodegradability, it decomposes early after composting and landfilling, so there is little impact on the environment.

Sectional drawing of the film which provided the components for chuck | zipper which consists of the recessed part material and convex part of this invention. Sectional drawing of the film which provided the components for chuck | zipper which consists of the convex member of this invention, a recessed part material, and a chuck | zipper base. Sectional drawing of the tape with a chuck | zipper which consists of the convex member of this invention, a recessed part material, and a large chuck | zipper base. Sectional drawing of the ti-film provided with the components for the chuck | zipper which consists of the recessed part material and convex member which shape stability fell.

Claims (3)

A chuck part having a chuck part for opening and closing the bag at the mouth part of the bag formed of a film mainly composed of aliphatic polyester, and the chuck part is formed of a convex member and a concave member that can be fitted to each other. a method of manufacturing a component chuck in biodegradable chuck bag made of the value of the flexural modulus is the 150MPa~ 300 MPa, the value of 70 ° C. storage elastic modulus of 10 ⁵ to 10 ⁷ Pa, fat After melting a resin composition mainly composed of a group polyester resin and extruding from a die having an opening for forming a chuck component, a chuck component composed of a convex member and a concave member is formed, and then a speed of 40 ° C. / A method for producing a chuck part for a biodegradable chuck bag comprising cooling at a second to 60 ° C./second.   2. The method for manufacturing a chuck part for a biodegradable chuck bag according to claim 1, wherein the film forming the bag and the aliphatic polyester as the main component of the chuck portion are polylactic acid resins. The component for chuck of a biodegradable chuck bag according to claim 1 or 2, further comprising 0.05 to 10 parts by mass of a crystallization nucleating agent with respect to 100 parts by mass of the resin composition constituting the chuck part. How to manufacture.

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