KR20170112731A - Manufacturing method of polylactic acid vessel having improved heat-resisting property, polylactic acid vessel manufactured by the manufacturing method, and manufacturing machine of the polylactic acid vessel - Google Patents

Abstract

A polylactic acid container manufacturing method improved in heat resistance, a polylactic acid container manufactured by the manufacturing method, and an apparatus for producing the polylactic acid container are disclosed.
A disclosed polylactic acid container manufacturing apparatus for producing a polylactic acid container, comprising: a polylactic acid film supply member for supplying a polylactic acid film containing polylausic acid and formed in a film form; A preheating member for preheating the polyphthalate film supplied by the polyphthalate film supplying member; A main heating member for heating the preheated polyphtic acid film via the preheating member for molding; A mold member for molding the poly (ethylacetate) film heated through the main heating member into a desired container form of the poly (lactic acid) container; And a temperature holding member for holding the temperature of the mold member at a required mold crystallization temperature, wherein the temperature of the mold member is maintained at the required mold crystallization temperature by the temperature holding member, And the poly (lactic acid) film introduced for molding is crystallized together with molding in the mold member.
According to the polylactic acid container manufacturing method, the polylactic acid container manufacturing apparatus, and the polylactic acid container manufacturing apparatus described above, which have improved heat resistance, a polylactic acid film supplying member, a preheating member, a main heating member, And a temperature holding member are used to produce a polylactic acid container so that the polylactic acid film drawn for the molding with the mold member can be crystallized together with the molding in the mold member, The polylactic acid container does not need to be subjected to a post-crystallization process after being molded in the mold member, so that the polylactic acid container can be improved in the production efficiency of the polylactic acid container while the crystallization process is performed to improve the heat resistance of the polylactic acid container There are advantages to be able to.

Description

Technical Field [0001] The present invention relates to a polylactic acid container having improved heat resistance, a polylactic acid container manufactured by the method, and a polylactic acid vessel manufactured by the manufacturing method, manufacturing machine of the polylactic acid vessel}

The present invention relates to a polylactic acid container manufacturing method with improved heat resistance, a polylactic acid container manufactured by the manufacturing method, and an apparatus for producing the polylactic acid container.

Polylactic acid (PLA) is an eco-friendly resin made from raw materials extracted from corn starch. It is a safe material because it does not detect harmful substances such as environmental hormones and heavy metals even if it contains hot food or infants are bitten or sucked , While it has the same characteristics as ordinary plastics during use, it is a material that is 100% biodegraded by microorganisms at the time of disposal.

The above polylactic acid is a biodegradable raw material, but its price is not relatively high and it can be used for various applications.

It is a polylactic acid container which is molded with such a polylactic acid and contains food or the like, and the following patent documents can be presented as an example of such a polylactic acid container.

There is also a method of melting polylactic acid and using a hopper and a mold to dip the polylactic acid container. However, since this method requires a long time for the operation, the working efficiency is lowered. Therefore, in order to increase the production efficiency, A polylactic acid container is manufactured by molding a lactic acid film using a mold.

The problem that is frequently encountered when producing containers made of poly (lactic acid) film is that poly (lactic acid) has a relatively low heat deflection temperature, so that the poly (lactic acid) container is thermally deformed during the distribution and storage stages of the poly Or damaged.

In order to solve such a problem and to improve the heat resistance of the polylactic acid container, the polylactic acid film was put into a mold, the container was molded into a desired shape, and a step of crystallizing the molded polylactic acid container was performed separately.

However, according to the conventional method of producing a poly (lactic acid) container, the post-process of molding a poly (lactic acid) film into a desired shape through a die working process involves crystallizing the formed poly The polylactic acid container thus formed was moved to a heated chamber and put into a heated chamber, and after crystallization, it had to be taken out again and moved, thereby causing a problem that the production efficiency of the polylactic acid container was greatly reduced there was.

Published Patent Application No. 10-2011-0045588 Disclosure of the Invention Title of the Invention Polylactic acid sheet having excellent heat resistance and container using the same

The present invention relates to a method for producing a polylactic acid container having improved heat resistance capable of improving the production efficiency of a polylactic acid container while performing a crystallization process for improving the heat resistance of the polylactic acid container, An object of the present invention is to provide a lactic acid container manufacturing apparatus.

According to an aspect of the present invention, there is provided a method for manufacturing a polylactic acid container with improved heat resistance, comprising the steps of: (a) forming a polylactic acid film extruded into a film by mixing polylactic acid and an additive; (b) preheating the poly (lactic acid) film formed in step (a) in a preheating member at a temperature in the range of 150 to 250 ° C; And (c) drawing the poly (ethylacetate) film preheated in the step (b) into a mold member, and molding and crystallizing the poly (lactic acid) film into a desired container form in the mold member.

A polylactic acid container according to one aspect of the present invention comprises: (a) a polylactic acid film extruded in a film form by mixing polylactic acid and an additive; and (b) (C) bringing the poly (ethylacetate) film preheated in the step (b) into a mold member to mold the poly (lactic acid) film into a desired container form in the mold member; And crystallizing the molten metal together with the molten metal, wherein crystallization is completed in the mold member at the same time as molding.

An apparatus for producing polylactic acid containers according to one aspect of the present invention is for producing polylactic acid containers,

A poly (lactic acid) film supply member for supplying a poly (lactic acid) film containing poly (lactic acid) and formed in a film form; A preheating member for preheating the polyphthalate film supplied by the polyphthalate film supplying member; A main heating member for heating the preheated polyphtic acid film via the preheating member for molding; A mold member for molding the poly (ethylacetate) film heated through the main heating member into a desired container form of the poly (lactic acid) container; And a temperature holding member for maintaining the temperature of the mold member at a required mold crystallization temperature,

Characterized in that the temperature of the mold member is maintained at the required molding crystallization temperature by the temperature holding member so that the poly (ethylacetate) film pulled in for the molding with the mold member is crystallized together with molding in the mold member .

According to the method for producing a polylactic acid container with improved heat resistance according to an aspect of the present invention, the polylactic acid container manufactured by the method and the apparatus for producing a polylactic acid container, the polylactic acid film supply member, the preheating member, A polylactic acid container is produced by using a polylactic acid container manufacturing apparatus including a mold member and a temperature holding member so that the polylactic acid film drawn for the molding with the mold member can be crystallized together with molding in the mold member So that the polylactic acid container is molded in the mold member and then subjected to a post-crystallization process in a separate device. Therefore, a crystallization process is performed to improve the heat resistance of the polylactic acid container, The manufacturing efficiency can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a configuration of an apparatus for producing polylactic acid containers according to an embodiment of the present invention; FIG.
FIG. 2 is a view showing a poly (lactic acid) film drawn into a mold member constituting an apparatus for producing a poly (lactic acid) container according to an embodiment of the present invention for molding; FIG.
Fig. 3 is an enlarged view of part A shown in Fig. 2; Fig.
4 is a view showing a state in which a poly (lactic acid) film is molded by the mold member shown in Fig. 2; Fig.
4 is a view showing a state in which a polylactic acid container is molded by the mold member shown in Fig. 4; Fig.
6 is a view showing the present heating member constituting an apparatus for producing a polylactic acid container according to an embodiment of the present invention.

Hereinafter, a method for manufacturing a polylactic acid container with improved heat resistance according to an embodiment of the present invention, a polylactic acid container manufactured by the method, and the apparatus for producing a polylactic acid container will be described with reference to the drawings.

FIG. 1 is a schematic view showing the construction of a polylactic acid container manufacturing apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a polylactic acid film forming apparatus according to an embodiment of the present invention, Fig. 3 is an enlarged view of part A shown in Fig. 2, Fig. 4 is a view showing a state where the poly (lactic acid) film is molded by the mold member shown in Fig. 2 FIG. 4 is a view showing a state in which the polylactic acid container is molded by the mold member shown in FIG. 4, and FIG. 6 is a view showing the present heating member constituting the apparatus for producing a polylactic acid container according to an embodiment of the present invention. FIG.

1 to 6 together show a polylactic acid container manufacturing apparatus 100 according to the present embodiment for producing a polylactic acid container 20. The apparatus 100 comprises a polylactic acid film supply member 101, A main heating member 130, a mold member 140, and a temperature holding member 150. The heating member 130,

The polyphthalate film supply member 101 supplies a polyphasic acid film 10 containing a poly (lactic acid) and formed in the form of a film, wherein the poly (ethy) acid film 10 is in contact with the poly And can be supplied while being unwound from the outermost periphery.

Here, the poly (ethylacid) film 10 can be formed by mixing the poly (lactic acid) with an additive and extruding the mixture into a film form. The additive to be added to the poly (lactic acid) may be at least one of talc, filler, and calcium carbonate.

The preheating member 110 preheats the poly (ethylacetate) film 10 supplied by the poly (ethylacetate) film supply member 101.

In detail, the preheating member 110 is arranged in a zigzag fashion up and down along the proceeding direction of the poly (ethylacetate) film 10 to form a plurality of preheating transfer rollers And a preheater 115 disposed below the preheat transfer roller 111 to transfer radiant heat to the polyphthalic acid film 10 moved along the preheat transfer roller 111 by being heated .

The main heating member 130 heats the preheated poly (ethylacetate) film 10 via the preheating member 110 for molding.

The main heating member 130 includes main heating heaters 131, 132, and 133 that gradually become finer in a progressing direction of the poly (ethylene terephthalate) film 10.

For example, as shown in FIG. 6, the first heating element 131, which can integrally heat the entire width direction of the poly (lactic acid) film 10, A second main heating body 132 which can heat the width direction of the poly (ethylacetate film) 10 via the first main heating body 131 in three equal parts, and a second main heating body 132 And a third main heating body 133 which can divide the width direction of the poly (ethylacetate film)

The polyethercanic film 10 can be gradually finely divided and heated by the main heating heaters 131, 132, and 133 gradually finely divided while moving along the proceeding direction of the poly So that the lactic acid film 10 can be accurately formed in the mold member 140.

The mold member 140 is to heat the heated poly (ethylacetate film) 10 via the heating member 130 into a desired container form of the poly (lactic acid) container 20.

In detail, the mold member 140 includes a lower mold body 142 for forming the desired bottom surface shape of the polythene container 20, and a lower mold member 142 for forming a desired upper surface shape of the poly A plurality of the molds 140 are inserted in at least one of the lower mold body 142 and the upper mold body 141 so that the heat applied by the temperature holding member 150 is transferred to the mold member 140 ) And an electrothermal material 145 for transferring for molding and crystallization as a whole.

Reference numeral 121 designates the lower mold body 142 and the upper mold body 141 to be in close contact with each other so that the mold member 140 can be formed by taking the poly (ethylacetate) film 10, The mold moving means.

The mold moving means 121 may be represented by a hydraulic cylinder, and the piston 122 may be connected to the upper mold body 141. Of course, it is an exemplary one that the mold moving means 121 is shown as a hydraulic cylinder, and that the piston 122 is connected to the upper mold body 141, Shaped body 142 as shown in FIG.

The heat transfer member 145 is installed in at least one of the upper mold member 141 and the lower mold member 142 and is provided in a plurality of units and is provided in a lattice form or the like so that the mold member 140 is uniformly To be heated.

A plurality of the heat transfer members 145 are disposed in the mold member 140 so as to be spaced apart from each other so that the surface temperature of the mold member 140 can be made uniform, Are arranged at the same depth from the surface of the member (140). 3, the surface of the mold member 140 may have a different height. In correspondence with this different height, the respective heat conductive members 145 may be formed so as to have the same height from the surface of the mold member 140 And is arranged in the same shape as the height of the surface of the mold member 140 as a whole.

When the mold member 140 is formed as described above, the surface of the mold member 140 can be uniformly heated, so that the molding and crystallization in the mold member 140 can be uniformed as a whole.

Meanwhile, the mold member 140 may be made of ceramic. That is, the mold member 140 may be formed by baking and ceramicizing the conductive member 145 in a lattice form or the like. Therefore, compared with a case where the mold member 140 is made of a metal material, the warmth of the mold member 140 is excellent, and the amount of heat generated by the heat conductive member 145 can be reduced.

The temperature holding member 150 keeps the temperature of the mold member 140 at a desired mold crystallization temperature.

The temperature of the mold member 140 is maintained at the required mold crystallization temperature by the temperature holding member 150 so that the polyphosphoric acid film 10 drawn in for the molding with the mold member 140, The polylactic acid container 20 can be crystallized together with the molding in the member 140 so that the polylactic acid container 20 does not need to be molded in the mold member 140 and then subjected to a crystallization process in a separate apparatus.

The molding crystallization temperature for molding and simultaneous crystallization of the poly (lactic acid) film 10 may be determined while changing the temperature of the mold member 140 in multiple stages.

For example, in the first stage of the molding crystallization, the temperature of the mold member 140 is maintained in the range of 50 to 60 캜, which is the glass transition temperature of the poly (ethylacetate) film 10, The temperature of the mold member 140 is maintained at a temperature between the glass transition temperature and the melting point of the poly (lactic acid) film 10, which is 90 to < RTI ID = 0.0 & The molding crystallization temperature, which is a temperature optimized for molding and crystallization of the poly (lactic acid) film 10, can be determined while the temperature is maintained at a temperature in the range of 100 to 100 ° C., The continuous molding process of the polylactic acid container 20 is performed in the mold member 140 under the environment in which it is maintained.

The temperature holding member 150 may circulate the circulating fluid to the heat transfer member 145 by heating the circulating fluid such as oil. In this case, Which circulates the circulating fluid. In this case, the heat transfer means 151 for connecting the temperature holding member 150 and the circulation member becomes a circulating fluid flow pipe.

The temperature holding member 150 may function as a power supply and a control unit for supplying and controlling electricity. In this case, the heat holding member 145 is electrically connected to the temperature holding member 150 by electricity supplied from the temperature holding member 150 It becomes a heat ray that generates heat. In this case, the heat transfer means 151 for connecting the temperature holding member 150 and the circulation member is a cable for supplying electricity.

The apparatus 100 for producing a polylactic acid liquid may further include an insulating sealing member 125.

The heat insulating sealing member 125 seals the mold member 140 adhered to the outside so as to prevent the mold member 140 heated and maintained by the temperature holding member 150 from being cooled .

The heat insulating sealing member 125 may surround the mold member 140 to form an isolation space from the outside, and a heat insulating film may be formed on the inner wall of the heat insulating sealing member 125.

The heat dissipation sealing member 125 can prevent the mold member 140 from being cooled arbitrarily so that energy consumption required for molding and crystallization in the mold member 140 can be reduced .

Hereinafter, a method of manufacturing the polylactic acid container 20 according to the present embodiment will be described with reference to the drawings using the apparatus for producing polylactic acid containers 100 described above.

First, a polylactic acid film 10 extruded in the form of a film is formed by mixing polylactic acid and an additive (step (a)).

In the step (a), the additive to be added to the poly (lactic acid) may be at least one of talc, filler and calcium carbonate, and 1 to 5 parts by weight of the additive may be added to 100 parts by weight of the poly (lactic acid) have.

The poly (ethylacetate) film 10 formed as described above is wound around the poly (ethylacetate) film supply member 101 and then supplied.

Then, the step of preheating the poly (ethylacetate) film 10 formed in the step (a) within the temperature range of 150 to 250 ° C is performed in the preheating member 110 (step (b)),

More specifically, the step (b) may include a preheating step of performing preheating while maintaining the temperature of the preheating member 110 in a range of 150 to 160 ° C, a preheating step of heating the temperature of the preheating member 110 Is preheated while maintaining the temperature of the preheating member (110) heated to 220 ° C and maintaining the temperature of the preheating member (110) through the preheating second stage, A preheating step 4 in which the preheating step is performed while the temperature of the preheating member 110 having been heated through the preheating step is increased to 230 ° C. and the preheating step is performed after the preheating step, And the preheating step is carried out while the temperature of the preheating step is maintained at 240 < 0 > C.

Then, the poly (ethylacetate) film 10 preheated in the step (b) is drawn into a mold member 140, and the poly (ethylacetate) film 10 is molded into the form of a container required in the mold member 140 (Step (c)).

Specifically, in the step (c), the temperature of the mold member 140 in the first stage of the molding crystallization is maintained in the range of 50 to 60 캜, which is the glass transition temperature of the poly (ethylacetate) film 10, The temperature of the mold member 140 is raised and maintained in the range of 70 to 80 ° C in the third step of the molding crystallization and the temperature of the mold member 140 is maintained between the glass transition temperature and the melting point of the poly The molding crystallization temperature, which is a temperature optimized for molding and crystallization of the poly (lactic acid) film 10, can be determined while maintaining the temperature within the range of 90 to 100 ° C, The polylactic acid container 20 is continuously mass-produced in the mold member 140 under the environment in which the polylactic acid container 20 is maintained by the continuous casting process.

Here, the first shaping crystallization step, the second shaping crystallization step, and the third shaping crystallization step may be performed for a range of 1 to 10 seconds, respectively.

The method of manufacturing the polylactic acid container 20 may further include a trimming step (step (d)) of removing the scrap of the polylactic acid container 20 molded and crystallized in the step (c).

At the outer periphery of the polylactic acid container 20 molded and crystallized in the step (c), scrap is formed, and such scrap is removed through the scrap removing member 160 having a blade or the like.

Since the poly (lactic acid) container 20 having been subjected to the above process has already been molded and crystallized in the mold member 140, a post-process for crystallization is not required separately.

Meanwhile, the poly (lactic acid) container 20 according to the present embodiment is formed by mixing a poly (lactic acid) with an additive to form a poly (lactic acid) film 10 extruded in a film form (step (a)), A step (b) of preheating the poly (ethylacrylate) film 10 in the preheating member 110 at a temperature in the range of 150 to 250 ° C; (b) And a step (c) of drawing the poly (lactic acid) film (10) into a container form required in the mold member (140) and crystallizing the poly (lactic acid) film And crystallization is completed in the mold member 140 at the same time as molding.

As described above, in the polylactic acid container manufacturing apparatus 1 including the polylactic acid film supply member 101, the preheating member 110, the main heating member 130, the mold member 140, and the temperature holding member 150, The polylactic acid film 10 is formed by using the mold member 100 so that the polylactic acid film 10 drawn for molding with the mold member 140 can be crystallized together with the molding in the mold member 140 The polylactic acid container 20 is formed in the mold member 140, and then it is not necessary to undergo a post-crystallization process in a separate device. Therefore, in order to improve the heat resistance of the polylactic acid container 20, The production efficiency of the poly (lactic acid) container 20 can be improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the following claims And can be changed. However, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

According to the method for producing a polylactic acid container with improved heat resistance according to one aspect of the present invention, the polylactic acid container manufactured by the method, and the apparatus for producing a polylactic acid container, a crystallization process is performed for improving the heat resistance of the polylactic acid container, The production efficiency of the poly (lactic acid) container can be improved, so that the possibility of industrial application is high.

100: polylactic acid container manufacturing device
101: Poly (lactic acid) film supply member
110:
130:
140: mold member
150: Temperature holding member

Claims (15)

A polylactic acid container manufacturing apparatus for producing a polylactic acid container,
A poly (lactic acid) film supply member for supplying a poly (lactic acid) film containing poly (lactic acid) and formed in a film form;
A preheating member for preheating the polyphthalate film supplied by the polyphthalate film supplying member;
A main heating member for heating the preheated polyphtic acid film via the preheating member for molding;
A mold member for molding the poly (ethylacetate) film heated through the main heating member into a desired container form of the poly (lactic acid) container; And
And a temperature holding member for maintaining the temperature of the mold member at a required mold crystallization temperature,
Characterized in that the temperature of the mold member is maintained at the required molding crystallization temperature by the temperature holding member so that the poly (ethylacetate) film pulled in for the molding with the mold member is crystallized together with molding in the mold member Wherein the apparatus is a polyla The method according to claim 1,
The mold member
A lower metal mold for forming a desired bottom face shape of the polylactic acid container,
An upper metal mold for forming a desired top surface shape of the polylactic acid container,
And a plurality of heaters arranged in an interpolated form in at least one of the lower mold and the upper mold to transfer the heat applied by the temperature holding member to the entire mold for molding and crystallizing. Wherein the polylactic acid is produced by the polylactic acid. 3. The method of claim 2,
A plurality of the heat transfer elements are disposed in the mold member so as to be spaced apart from each other so that the surface temperature of the mold member can be made uniform and each of the heat transfer elements is disposed at the same depth from the surface of the mold member Wherein the apparatus is a polyla 3. The method of claim 2,
Wherein the mold member is made of ceramic. The method according to claim 2 or 4,
Wherein the temperature holding member circulates the circulating fluid to the heat transfer body by heating the circulating fluid,
Wherein the heat transfer member is a pipe for circulating the circulating fluid circulated in the temperature holding member. The method according to claim 2 or 4,
The temperature holding member is for supplying and controlling electricity,
Wherein the heating element is a heating wire generated by electricity supplied from the temperature holding member. The method according to claim 1,
The polylactic acid container manufacturing apparatus
And a heat insulating sealing member for insulating the mold member from the outside so as to prevent cooling of the mold member heated and maintained by the temperature holding member. (a) a polylactic acid film extruded in a film form by mixing polylactic acid and an additive;
(b) preheating the poly (lactic acid) film formed in step (a) in a preheating member at a temperature in the range of 150 to 250 ° C; And
(c) drawing the poly (ethylacetate) film preheated in the step (b) into a mold member, and molding the poly (lactic acid) film into a container form required in the mold member and crystallizing the same; A method for producing a polylactic acid container. 9. The method of claim 8,
The method of claim 1, wherein the step (c) comprises: a first molding step of keeping the temperature of the mold member at a glass transition temperature of 50 to 60 ° C of the poly (lactic acid) film; And a mold crystallization step of heating the mold member in a temperature range of 90 to 100 DEG C, which is a temperature between a glass transition temperature and a melting point of the poly (lactic acid) film, It is possible to determine the molding crystallization temperature which is a temperature required for molding and crystallization of the lactic acid film and to carry out the molding process of the polylactic acid container in the mold member under the environment in which the predetermined molding crystallization temperature is maintained by the temperature holding member Wherein the polylactic acid is a polylactic acid. 10. The method of claim 9,
Wherein the forming crystallization first step, the shaping crystallization second step and the shaping crystallization third step are performed for a range of 1 to 10 seconds, respectively. 9. The method of claim 8,
The step (b)
A preheating step in which preheating is performed while maintaining the temperature of the preheating member in a range of 150 to 160 ° C,
A preheating second step in which the preheating is performed while the temperature of the preheating member having undergone the preheating first step is raised and maintained in a range of 190 to 200 ° C,
A preheating step 3 in which the preheating is performed while the temperature of the preheating member having undergone the preheating second step is raised to 220 캜 and maintained,
A preheating step (4) in which the preheating is performed while the temperature of the preheating member after the preheating step (3)
And a preheating step (5) wherein the preheating step is performed while the temperature of the preheating member after the preheating step (4) is raised to 240 캜 and maintained. 9. The method of claim 8,
Wherein the additive added to the poly (lactic acid) in the step (a) is at least one of talc, filler, and calcium carbonate. 9. The method of claim 8,
Wherein the additive is added in an amount of 1 to 5 parts by weight based on 100 parts by weight of the poly (lactic acid) in the step (a). 9. The method of claim 8,
The polylactic acid container manufacturing method
(d) a trimming step of removing scrap of the poly (lactic acid) container formed and crystallized in the step (c). (a) a polylactic acid film extruded in the form of a film by mixing polylactic acid and an additive; and (b) preheating the polylactic acid film formed in the step (a) in a preheating member at 150 to 250 ° C And (c) drawing the poly (ethylacetate) film preheated in the step (b) into a mold member to form the poly (lactic acid) film into a container form required in the mold member and crystallizing the poly Wherein the polylactic acid is produced by a container manufacturing method, and the polylactic acid container is completed to be molded and crystallized in the mold member.

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