JP2013170003A - Film welding method and device, method for producing packaged food and method for producing packaged fermented soybean - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film welding method by which a resin film can be sealed reliably, efficiently and stably to a container formed of foamed resin.SOLUTION: A method for welding a resin film 13 to a container 11 formed of a foamed resin having a buckling strength of 3.0 to 30.0 kgf is provided. A welding temperature is set in 80 to 240°C. Pressure when the resin film 13 is pressed against the container 11 is set at 1.0 to 6.2 kgf/cm.

Description

  The present invention relates to a film welding method and apparatus, a method for producing food in a container, and a method for producing natto in a container.

  Conventionally, various containers having a storage unit for storing the articles to be stored have been proposed. As specific examples, for example, a natto container having a storage recess for storing natto and seasonings is well known. Yes. Usually, this type of container is provided with an opening on the upper end surface for inserting / removing objects to / from the storage unit. And after storing a to-be-stored object in a storage part, the to-be-stored object is sealed by covering the opening with a resin film. In addition, several devices for performing such sealing have been proposed in the past (see, for example, Patent Documents 1 and 2). Further, as a method of covering and sealing the opening of the container, generally, a method in which a resin film is thermally welded so as to cover the entire upper end surface of the container and then a surplus portion is cut (so-called trimming) is widely adopted. ing.

  Here, there is a case where it is desired to seal the resin film by heat-welding to a container having an opening in only a part, not a container having an opening in the entire upper end surface of the container. In this case, it is necessary to use a resin film having an area larger than at least the opening. However, when sealing, for example, if the resin film protrudes from the outer edge portion of the upper end surface of the container, the appearance is deteriorated and the appearance is deteriorated. Further, not only the appearance is deteriorated, but also the amount of the resin film used is increased and the cost is lowered. Furthermore, even if the resin film is cut and trimmed after heat welding, a cutting means such as a blade comes into contact with a portion surrounding the opening in the container and damages the container. Therefore, the above-described sealing method has some disadvantages, and there is a problem that it is difficult to adopt in practice.

  Therefore, a sealing method capable of sealing the container without causing the resin film to protrude from the outer edge portion of the upper end surface of the container is desired, and a film welding apparatus (cover material mounting apparatus) capable of realizing such a sealing method. Has been conventionally proposed (see, for example, Patent Document 3).

  In this apparatus, first, a lid material is punched from a film material at a lid material punching portion. The punched lid member has a size and shape necessary to cover the opening. At substantially the same time as this operation, the lid member suction part operates to suck and hold the punched lid member. The lid suction part that adsorbs the lid is thermally welded by transferring the lid to the upper end surface of the container and applying a temperature for a predetermined time by pressing the lid.

JP 2003-252301 A JP 2002-179124 A JP 2010-6375 A

  By the way, this inventor provides a recessed part in the cover of a natto container provided with a container main body and a cover, stores food in the recessed part, and heat-welds the resin film to the upper end surface having the opening by the above method. I am thinking of that. However, food containers generally represented by natto containers and the like are weak in strength because they are made of foamed resin, and the strength itself varies. Therefore, in the case of a film welding apparatus of a type that presses and heats a resin film having a predetermined shape in advance, problems such as container breakage or leakage of contents due to insufficient sealing are likely to occur, and stable sealing is performed while avoiding these problems. It was difficult. Therefore, conventionally, it is necessary to severely set the conditions at the time of sealing, which has been a factor that hinders productivity improvement.

  The present invention has been made in view of the above problems, and an object thereof is to provide a film welding method and an apparatus therefor capable of reliably and stably sealing a resin film against a foamed resin container. There is. Another object of the present invention is to provide a method capable of efficiently and reliably producing food in a container or natto in a container by sealing the container by the excellent method as described above.

  Means [1] to [5] for solving the above problems are listed below.

[1] A method of welding a resin film to a foamed resin container having a buckling strength of 3.0 kgf or more and 30.0 kgf or less, wherein the welding temperature is set to 80 ° C. or more and 240 ° C. or less, and film deposition method characterized by setting the pressure for pressing the resin film to 1.0 kgf / cm ² or more 6.2kgf / cm ² or less.

  Therefore, according to the invention described in the means 1, by setting the welding temperature and the pressing force at the time of welding within the above-described preferable range, it is possible to reliably and stably avoid problems such as container destruction and content leakage. Can be sealed. Therefore, it is not always necessary to severely set the conditions at the time of sealing, and productivity can be easily improved.

  Here, a foamed resin container having a buckling strength of 3.0 kgf to 30.0 kgf is targeted. In the present specification, “buckling strength” means the strength with which a container can withstand vertical compression when sealing a foamed resin container. The “buckling strength” can be measured according to the following procedure using an apparatus such as a compression tester strograph (model VES5D manufactured by Toyo Seiki Seisakusho). First, the container with the lid closed is set directly under the compression tester, and the container is compressed by applying force from the top (the vertical direction of the container) with the compression tester (compression speed: 50 mm / min). The maximum intensity (peak) until the main body breaks is obtained. This value is defined as “buckling strength”.

  In the film welding method, the welding temperature is set to 80 ° C. or higher and 240 ° C. or lower. By setting the welding temperature within such a preferable range, a suitable sealing property can be obtained. This is because if the welding temperature is less than 80 ° C., the strength of the heat-welded portion may be insufficient and the sealing performance may be reduced. In addition, when trying to increase the strength of the heat-welded part by such low-temperature treatment, it is necessary to set the pressure when pressing the resin film higher or set the welding time longer, and the container will be destroyed. This is likely to lead to a decrease in productivity. On the other hand, if the welding temperature is higher than 240 ° C., the resin film or the foamed resin may be altered or deformed. In this case, the sealing performance may be lowered. In addition, when trying to avoid alteration and deformation by such high-temperature processing, it is necessary to set the welding time very short, so that the process becomes unstable and the strength of the heat-welded portion tends to vary.

In the above-described film deposition method, setting the pressure for pressing the resin film to the container 1.0 kgf / cm ² or more 6.2kgf / cm ² or less. By setting the film pressing force within such a preferable range, it is possible to obtain a suitable sealing property while avoiding the destruction of the container. This is because if the film pressing force is less than 1.0 kgf / cm ² , the strength of the heat welded portion may be insufficient, and the sealing performance may be deteriorated. Further, if the strength of the heat-welded portion is increased with such a film pressing force, the welding temperature must be set higher, and the resin film and the container are easily altered and deformed. On the other hand, if the film pressing force exceeds 6.2 kgf / cm ² , the vertical compressive force applied to the container becomes too large, and the container may be destroyed. The film pressing force ^is more preferably ^{3.0kgf / cm 2 ~6.2kgf / cm 2} , 4.5kgf / cm 2 ~6.0kgf / cm 2 is particularly preferred.

[2] The film welding method according to means 1, wherein the welding time is set as follows according to the temperature range of the welding temperature.
80 ° C or more and less than 100 ° C temperature range: 3 seconds or more and 9 seconds or less,
Temperature range from 100 ° C to less than 140 ° C: 0.4 seconds to 9 seconds,
140 ° C or more and less than 200 ° C temperature range: 0.2 seconds or more and 9 seconds or less,
Temperature range from 200 ° C. to less than 240 ° C .: 0.2 second to 1 second.

  Therefore, according to the invention described in the means 2, since a suitable welding time is set according to the temperature range of the welding temperature, it is possible to reliably obtain a suitable sealing property in each temperature range, and to produce It is possible to efficiently and stably seal without reducing the performance. Here, the preferred range of the welding time tends to be shorter as the welding temperature becomes higher, but if the welding time is less than the lower limit value of the preferred range in each temperature range, the amount of heat necessary for thermal welding cannot be given. In addition, the strength of the heat welded portion may be insufficient, and the sealing performance may be reduced. On the other hand, if the welding time exceeds the upper limit value of the preferred range in each temperature range, the amount of heat exceeding the amount of heat necessary for heat welding is given, resulting in alteration or deformation of the resin film or foamed resin. There is a possibility that it may occur, and the sealing performance may be reduced. In this case, the productivity may be reduced.

  [3] A method for producing a food in a container, comprising filling a foamed resin container with food and then welding and sealing the resin film by the method described in Means 1 or 2.

  Therefore, according to the invention described in the means 3, after the foamed resin container is filled with food, welding is performed in this state, so that the opening of the housing recess is covered with the resin film and efficiently sealed. Therefore, it is possible to efficiently and reliably produce a food in a container in which food is stored in the storage recess.

  [4] Using a foamed resin natto container comprising a container body having a natto storage recess and a lid having a seasoning storage recess that opens at the upper surface, natto is stored in the natto storage recess, and the seasoning storage A method for producing natto in a container comprising a recess containing a liquid seasoning for natto, wherein after filling the seasoning storage recess with a liquid seasoning for natto, a resin according to the method described in means 1 or 2 A method for producing natto in a container, wherein a film is welded and the seasoning storage recess is sealed.

  Therefore, according to the invention described in the means 4, after the seasoning storage recess is filled with the liquid seasoning for natto, welding is performed in this state so that the opening of the seasoning storage recess is covered with the resin film. Well sealed. Therefore, it is possible to efficiently and surely manufacture natto in a container in which a liquid seasoning for natto is stored in the lid.

  [5] An apparatus for welding a resin film to a foamed resin container by the method described in means 1 or 2, and a cutting means for cutting out a resin film having a predetermined shape and size from the original film of the resin film; And a holding means for pressing the resin film to a predetermined position of the container in a state where the cut-out resin film is held and heated.

  Therefore, according to the invention described in the means 5, the holding means holding the resin film cut out by the cutting means can be pressure-bonded to a predetermined position of the container while the resin film is heated. Therefore, according to this apparatus, the excellent method described in the means 1 can be easily and reliably realized, and the foamed resin container can be reliably sealed.

  Therefore, according to invention of Claim 1, 2, the film welding method which can seal a resin film reliably with respect to a foamed resin container can be provided.

  According to invention of Claim 3, the method which can manufacture a foodstuff with a container efficiently and reliably can be provided by sealing a container efficiently with the above outstanding methods.

  According to invention of Claim 4, the method which can manufacture natto containing a container efficiently and reliably can be provided by sealing a container efficiently with the above outstanding methods.

  According to the invention described in claim 5, since the resin film can be reliably and stably sealed without protruding from the outer edge of the foamed resin container, the above excellent sealing method is realized. It is possible to provide a film welding apparatus that can be used.

The top view which shows the natto container which is a to-be-sealed thing in embodiment which actualized the film welding method and film welding apparatus of this invention. The front view which shows a natto container (after a cover is closed and after sealing). The schematic sectional drawing of the natto container of FIG. The schematic sectional drawing when the natto container of FIG. 2 is cut at another position. The principal part expansion schematic for demonstrating the container sealing process by a film welding apparatus. The principal part expansion schematic for demonstrating the container sealing process by a film welding apparatus.

  Hereinafter, a film welding apparatus according to an embodiment embodying the present invention will be described in detail with reference to FIGS.

  The film welding apparatus of this embodiment is used in the manufacturing process of containered natto. First, the natto container, which is an object to be sealed, will be described.

  As shown in FIG. 1 to FIG. 4, the natto container 11 of the present embodiment stores the natto 2 and the liquid seasoning 3 for natto separately inside, and if necessary, a liquid seasoning for natto This is a food container having a structure in which 3 can be poured into natto 2. This natto container 11 is a container comprising a molded body 12 made of a foamed resin sheet and a resin film 13, and the molded body 12 made of a foamed resin sheet has a structure including a container body 22, a lid body 23, and a hinge portion 24. have. The container body 22 has a rectangular shape in plan view, and has a natto storage recess 25 in which an opening 26 is formed on the upper side. The natto 2 is stored in the natto storage recess 25. The lid 23 is a portion for closing the opening 26 of the container main body 22, and has a rectangular shape in plan view like the container main body 22. The container body 22 and the lid body 23 are connected via a hinge part 24.

  As shown in FIG. 1 and the like, the molded body 12 made of a foamed resin sheet constituting the natto container 11 is preferably within 3 mm in thickness, and here, one having a thickness of about 1.5 mm is used. . As the resin constituting the foamed resin sheet, a foamed polystyrene resin is used, but a foamed polyethylene resin, a foamed polyurethane resin, or the like may be used. In the molded body 12 made of the foamed resin sheet, the direction of the short side (that is, the left-right direction in FIG. 1) is the winding direction of the original sheet (longitudinal direction of the original sheet). The molded body 12 made of a foamed resin sheet has a large number of bubbles inside. These bubbles are rotating ellipsoidal (or spheroid) independent bubbles, and their major axes are arranged along a certain direction. This direction is referred to as “bubble orientation direction D1”. Therefore, in the molded body 12 made of the foamed resin sheet, it can be understood that the bubbles are oriented in the direction of the short side.

  As shown in FIGS. 1 to 4, the lid body 23 of the present embodiment has a circular surrounding ridge 30 on the lid outer surface 23 a (opening end surface), and an inner region of the surrounding ridge 30. Is a seasoning storage recess 32 opened at the lid outer surface 23a. In the seasoning storage recess 32, a pair of pressed portions 38 having a shape protruding toward the lid outer surface 23a side are provided. These pressed parts 38 are arranged opposite to both sides of the lid 23 with the cleavage groove 31 interposed therebetween.

  As shown in FIGS. 1 to 4, a resin film 13 having flexibility and liquid impermeability is thermally welded to the lid outer surface 23 a side of the lid 23. The resin film 13 is not particularly subjected to uneven processing, and has a substantially flat and simple configuration. The resin film 13 in the present embodiment is obtained by cutting out a piece having an outer diameter and a dimension corresponding to the outer shape and dimensions of the circular surrounding ridge 30 from the original film. Therefore, the resin film 13 is formed so as to be slightly larger than the seasoning storage recess 32 and not to protrude from the outer edge of the lid outer surface 23 a of the lid 23.

  As the resin forming the resin film 13, a general-purpose thermoplastic resin such as polyethylene or polypropylene, for example, can be used. The resin film 13 is a central portion (specifically, the surrounding ridge) of the lid outer surface 23 a (that is, the opening end surface). 30), the liquid seasoning 3 for natto in the seasoning storage recess 32 is hermetically sealed. The resin film 13 can be selected regardless of whether it is transparent or opaque. For example, in the former case, even after storage, the state of the liquid seasoning 3 for natto can be visually confirmed or confirmed by an inspection machine. Further, the position where the pair of pressed parts 38 are present can be visually confirmed. If it is the latter, deterioration of the liquid seasoning 3 for natto due to light can be prevented. Here, as the liquid seasoning 3 for natto, a liquid natto sauce or the like is given as a specific example. Moreover, in this embodiment, although the back surface of the resin film 13 is not in contact with the upper surface of a pair of to-be-pressed part 38, both may contact and may be heat-welded mutually.

  Next, the film welding apparatus 41 of this embodiment is demonstrated based on FIG. 5, FIG. The film welding apparatus 41 includes a conveyor device 43 that conveys the main frame 42 and the natto container 11 in a loaded state.

  A subframe (not shown) is disposed above the main frame 42. A first air cylinder (not shown) and a second air cylinder (not shown) are attached to the subframe. A cutting means 51 having a blade 52 is connected to the second air cylinder, and when the second air cylinder is driven, the cutting means 51 moves up or down (retracting or moving forward). . The cutting means 51 plays a role for cutting out the circular resin film 13 having a predetermined size from the original film of the resin film 13. FIG. 5 shows a state before the cutting means 51 cuts out the resin film 13.

  The first air cylinder is connected to a heat tool 61 as a holding means and a pressure bonding means. The heat tool 61 is a substantially columnar member, and is disposed above and coaxially with the cutting means 51 in a state (initial state) before starting the film cutting operation. An adsorption recess 63 is formed on the lower end surface 62 of the heat tool 61. A plurality of vacuum suction passages 64 are formed in the heating plate 61 a of the heat tool 61, and vacuuming means (not shown) is connected via the vacuum suction passages 64 and the hose 65. The cut-out resin film 13 is vacuum-sucked by evacuation and is held on the lower end surface 62.

  When the first air cylinder is driven, that is, it passes through the inner hole 53 of the cutting means 51, the heat tool 61 moves upward or downward (retracting or moving forward). The natto container 11 placed on the conveyor device 43 is disposed at the tip of the forward movement of the heat tool 61. The lower end surface 62 of the heat tool 61 can reach the lid outer surface 23a of the natto container 11, and can transfer and press the resin film 13 to the lid outer surface 23a. FIG. 6 shows a state in which the heat tool 61 holding and transferring the resin film 13 cut out by the cutting means 51 presses the resin film 13 on the lid outer surface 23a.

  Next, several methods for producing natto in a container using the film welding apparatus 41 of the present embodiment will be specifically described.

(First manufacturing method)
The first manufacturing method is as follows. First, the natto container 11 in the state shown in FIG. 1 is prepared, and the lid outer surface 23a side is directed downward, and the opening 26 side of the natto storage recess 25 in the container body 22 is disposed upward. Then, a predetermined amount of steamed soybean is filled into the natto storage recess 25 in the container body 22 of the natto container 11 using a filling device (not shown) (steamed soybean filling step). Next, the natto container 11 filled with steamed soybeans is folded at the hinge portion 24 and the lid 23 of the natto container 11 is closed so as to close the natto storage recess 25 (lid closing step). Next, a predetermined amount of the liquid seasoning 3 for natto is filled in the seasoning storage recess 32 in the lid 23 using another filling device (not shown) (seasoning filling step). Next, using the film welding apparatus 41 of FIGS. 5 and 6, the resin film 13 is thermally welded so as to close the opening of the seasoning storage recess 32 filled with the liquid seasoning 3 for natto, and the seasoning is stored. The concave portion 32 is sealed so as not to leak (the sealing step by the above film welding). Next, the natto container 11 filled with the steamed soybeans and the liquid seasoning 3 for natto is stored for a predetermined time in the fermentation chamber to perform natto fermentation (fermentation process), thereby completing the desired containered natto. .

(Second manufacturing method)
The second manufacturing method is as follows. First, the natto container 11 in the state shown in FIG. 1 is prepared, and the lid outer surface 23a side is directed downward, and the opening 26 side of the natto storage recess 25 in the container body 22 is disposed upward. And the natto storage recessed part 25 in the container main body 22 of the natto container 11 is filled with a predetermined amount of steamed soybeans using a filling device (not shown) (steamed soybean filling step). Next, the natto container 11 in which the natto storage recess 25 is filled with steamed soybeans is bent by the hinge portion 24, and the lid 23 is closed so as to close the natto storage recess 25 (lid closing step). Next, the natto container 11 filled with steamed soybeans is stored in the fermentation room for a predetermined time to perform natto bacteria fermentation (fermentation process). Next, the liquid seasoning 3 for natto is filled in the seasoning storage recess 32 in the lid 23 (seasoning filling step). Next, using the film welding apparatus 41 of FIGS. 5 and 6, the resin film 13 is thermally welded so as to close the opening of the seasoning storage recess 32 filled with the liquid seasoning 3 for natto, and the seasoning is stored. The recess 32 is sealed so as not to leak (sealing step by the above-mentioned film welding), and a desired containered natto is completed.
Hereinafter, examples in which the embodiment is more specific will be described.

[Example 1]
In Example 1, the natto container 11 (with a buckling strength of 14 kgf to 20 kgf) having the structure shown in the above embodiment was used as a sample. After filling a predetermined amount of the liquid seasoning 3 for natto into the seasoning storage recess 32 in the lid 23 of the natto container 11, a resin film is used to close the opening of the seasoning storage recess 32 using a film welding device 41. 13 was heat-welded. At that time, the welding temperature (° C.) and the welding time (seconds) were set as shown in Table 1. In welding, the pressing amount of the heat tool 61 was uniformly set to 3 mm. The measured value of the film pressing force at that time was about 4.5 kgf / cm ² . The pressing amount refers to an amount when the heat tool 61 is pressed from the position where the resin film 13 and the lid 23 of the natto container 11 are in contact with each other.

  And the container 11 immediately after welding was visually observed as it was, and the presence or absence of the liquid leak from a seal part was investigated (normal test). In addition, in order to predict the possibility of occurrence of “post-process defects”, whether or not the resin film 13 is slightly peeled by visual observation after setting a severe condition that the container 11 immediately after welding is intentionally distorted. (Severe test). In this evaluation test, 10 samples were used in one test section.

Evaluation was made into three grades of "◎", "○", and "x". Specifically, “◎” indicates that 10 out of 10 samples did not leak and there was no possibility of occurrence of defects in the post-process. “◯” indicates that there is no possibility of a post-process failure although there is no liquid leakage for 10 out of 10 samples. “X” indicates that liquid leakage occurred in one or more of 10 samples. The results are shown in Table 1.

[Example 2]

In Example 2, the same test as in Example 1 was performed. Here, the welding temperature was uniformly set to 160 ° C. and the welding time was set to 1 second. On the other hand, as shown in FIG. 1, several pressing amounts of the heat tool 61 were set within a range of 0 mm to 10 mm, and welding was performed. Table 2 shows the film pressing force at that time. Since the pressing force is very small when the pressing amount is 0 mm to 0.4 mm, the measured value is 0.0 kgf / cm ² .

  And also in this evaluation test, while using 10 samples in 1 test section, the natto container 11 immediately after welding was visually observed as it was, and the presence or absence of the liquid leak from a seal part was investigated.

Evaluation was made into two grades of "(circle)" and "x". Specifically, “◯” indicates that there was no liquid leakage for 10 out of 10 samples, and “X” indicates that there was liquid leakage for one or more of the 10 samples. . The results are shown in Table 2.

As is apparent from Table 2, as a result of the test, when the pressing amount was 0.9 mm or less, that is, when the film pressing force at the time of welding was 0.7 kgf / cm ² or less, some liquid leakage occurred. Therefore, under such condition setting, the strength of the heat-welded portion becomes insufficient, and the required suitable sealing performance cannot be obtained. On the contrary, when the pressing amount was 11 mm, that is, when the film pressing force during welding exceeded 6.2 kgf / cm ² , the natto container 11 came to break. In contrast, when the pressed amount of 1 mm to 10 mm, i.e. when the film pressing force at the time of welding of 1.0kgf ^/ cm ² ~6.2kgf ^/ cm 2 is not cause liquid leakage, natto container 11 also destroys There wasn't. Therefore, in order to give sufficient strength to the heat-welded portion and obtain the necessary suitable sealing properties, the pressing amount is set to 1 mm to 10 mm (film pressing force is set to 1.0 kgf / cm ^{2 to} 6.2 kgf / It was concluded that it must be set to cm ² . In consideration of the fact that the foamed resin natto container 11 has a considerable variation in strength, for example, the pressing amount is set to ² mm to 10 mm (film pressing force is set to 3.0 kgf / cm ^{2 to} 6.2 kgf / cm ² ), and the pressing amount was set to 3 mm to 8 mm (the film pressing force was set to 4.5 kgf / cm ^{2 to} 6.0 kgf / cm ² ).

  As described above, the present embodiment is characterized in that the welding temperature and the film pressing force at the time of welding are set in the above-described preferable range. For this reason, it can seal reliably and stably, avoiding malfunctions, such as container destruction and the leakage of the contents. Therefore, it is not always necessary to severely set the conditions at the time of sealing, and productivity can be easily improved. Furthermore, in this embodiment, since a suitable welding time is set according to the temperature range of the welding temperature, it is possible to surely obtain a suitable sealing property in each temperature range, and efficiency without reducing the productivity. It can seal well well.

  In addition, you may change embodiment of this invention as follows.

  -In above-mentioned embodiment, although the container main body 22 and the cover body 23 were integrally formed, you may form as a different body, respectively. Moreover, the separation process part (perforation etc.) for isolate | separating the container main body 22 and the cover body 23 may be formed in the hinge part vicinity.

  In the above embodiment, the blade 52 is employed as the cutting portion of the cutting means 51, and the cutting process is performed by moving the cutting means 51 in the axial direction (downward) of the cylindrical body in the cutting process. However, when the blade 52 is employed as the cutting portion, the cutting process may be performed by moving the blade 52 in a direction (for example, circumferential direction) different from the axial direction. Further, instead of a member such as the blade 52, for example, a cutting means including a laser processing machine as a cutting portion may be used.

  -Although the film welding apparatus 41 of the said embodiment was provided with the cutting means 51 which cuts out the resin film 13 of predetermined shape and magnitude | size from the raw fabric of the resin film 13, instead of this, for example, predetermined shape and Means for punching out the resin film 13 having a size may be provided.

  In the film welding apparatus 41 of the above embodiment, the heat tool 61 serves as both the holding means and the pressure bonding means for the resin film 13, but the holding tool and the pressure bonding means may be provided separately.

  In the above embodiment, the present invention is embodied in the natto container 11 in which the natto 2 is stored in the natto storage recess 25 and the liquid seasoning 3 for natto is stored in the seasoning storage recess 32, but other than the natto container Of course, the food container may be embodied. Furthermore, it can also be embodied in a container for storing things other than food.

DESCRIPTION OF SYMBOLS 2 ... Natto 3 ... Liquid seasoning for natto 11 ... Natto container as a container 13 ... Resin film 22 ... Container body 23 ... Lid body 25 ... Natto storage recessed part 32 ... Seasoning storage recessed part 41 ... Film welding apparatus 51 ... Cutting means 61 ... Heat tool as holding means

Claims (5)

A method of welding a resin film to a foamed resin container having a buckling strength of 3.0 kgf or more and 30.0 kgf or less,
Sets the welding temperature to 80 ° C. or higher 240 ° C. or less, the film welding and sets the pressure when pressing said resin film to said container below 1.0 kgf / cm ² or more 6.2kgf / cm ² Method. 2. The film welding method according to claim 1, wherein the welding time is set as follows according to the temperature range of the welding temperature.
80 ° C or more and less than 100 ° C temperature range: 3 seconds or more and 9 seconds or less,
Temperature range from 100 ° C to less than 140 ° C: 0.4 seconds to 9 seconds,
140 ° C or more and less than 200 ° C temperature range: 0.2 seconds or more and 9 seconds or less,
Temperature range from 200 ° C. to less than 240 ° C .: 0.2 second to 1 second.   A method for producing a food in a container, comprising filling a foamed resin container with a food and then welding and sealing the resin film by the method according to claim 1. Using a foamed resin natto container having a container body having a natto storage recess and a lid having a seasoning storage recess that opens at the upper surface, natto is stored in the natto storage recess, and natto is stored in the seasoning storage recess A method for producing natto in a container containing a liquid seasoning for use,
After filling the said seasoning accommodation recessed part with the liquid seasoning for natto, the resin film is welded by the method of Claim 1 or 2, and the said seasoning accommodation recessed part is sealed, Production method. An apparatus for welding a resin film to a foamed resin container by the method according to claim 1 or 2,
A cutting means for cutting out a resin film of a predetermined shape and size from the raw film of the resin film;
A film welding apparatus including holding means for pressing the resin film to a predetermined position of the container in a state where the cut out resin film is held and heated.

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