JPWO2012011558A1 - Check valve, manufacturing method thereof, and container provided with check valve - Google Patents

Abstract

In order to provide a check valve that can sufficiently suppress the mixing of air into a container even when an impact is applied to the container and can stably maintain the excellent discharge performance of the contents, the check according to the present invention The valve 10 is made of a rubber material and manufactured by integral molding, and has a cylindrical main body 1 having openings 1a and 1b at both ends, and a lid disposed so as to close one opening 1a of the main body 1. Part 3 and hinge part 5 which connects body part 1 and lid part 3 are provided, and lid part 3 has a protruding part 3a which contacts the peripheral edge part of opening 1a of body part 1 on side face 3b.

Description

  The present invention relates to a check valve, a method for manufacturing the check valve, and a container including the check valve.

  Some foods and beverages gradually deteriorate in quality over time, and the cause is oxidation due to contact with air. A so-called vacuum container is known as a container for suppressing the oxidation of the contents (see, for example, Patent Document 1).

  In the container described in Patent Document 1, a check valve that prevents air from entering the container is attached to the spout. This check valve has a structure in which a cut is provided in the dome-shaped head, and the cut opens when pressure is applied in the direction of dispensing the contents, and conversely closes when pressure is applied in the filling direction. It has become.

JP 10-338239 A

  By the way, when manufacturing a container with a check valve built into the spout, the size of the container spout is designed according to the type and viscosity of the contents, and the check valve should be built into the spout accordingly. The size of is determined. For example, when a vacuum container is employed as a soy sauce container used at a table and a check valve is provided at the spout, the outer diameter of the check valve is limited to about 10 to 15 mm. In order to produce such a small check valve in large quantities at low cost, integral molding using a mold is suitable.

  The inventors of the present invention prototyped various types of check valves and containers including the same by integral molding, and evaluated the presence or absence of air in the container and the discharge of contents. As a result, the check valve 50 shown in FIG. 8 finds that when an impact is applied to the container, the lid portion 53 enters the cylindrical main body portion 51, and the lid portion 53 does not sufficiently function as a valve. (See Comparative Example 1). A hinge portion 55 shown in FIG. 8 is a portion connecting the main body portion 51 and the lid portion 53.

  The present invention has been made in order to solve the above-described problems, and even when an impact is applied to the container, air can be sufficiently suppressed from being mixed into the container, and the excellent discharge property of the contents can be stably maintained. It is an object of the present invention to provide a check valve that can be maintained at the same time and a container having the check valve. It is another object of the present invention to provide a method for manufacturing a check valve that exhibits the above effects sufficiently efficiently and at low cost.

  The check valve according to the present invention is made of a rubber material and manufactured by integral molding, and has a cylindrical main body portion having openings at both ends, and a lid portion disposed so as to close one opening of the main body portion. And a hinge portion for connecting the main body portion and the lid portion and opening one opening when a force is applied to the lid portion from the main body portion side toward the outside. The side surface has a protruding portion that comes into contact with the peripheral edge of one of the openings.

  The check valve is provided with a protrusion on the side surface of the lid, and in a state where one opening of the main body is closed, this protrusion contacts the peripheral edge of the one opening of the main body. Touch. By providing such a projecting portion, even if an impact is applied to the check valve, the lid portion hardly enters the opening of the main body portion, and the lid portion can stably exhibit the function of the valve.

  By the way, the protrusion provided on the side surface of the lid portion is a portion that becomes a so-called undercut in the molding process. When a molded body is manufactured by integral molding, if there is an undercut portion, the portion is caught at the time of mold release, and the molded body cannot be properly taken out from the mold, and in some cases, the molded body is damaged. On the other hand, if the number of parts of the mold is increased so that an undercut portion does not occur, another problem that costs increase is caused.

  The check valve of the present invention can sufficiently avoid the problems caused by undercut without using a special mold. That is, since the check valve of the present invention is made of a rubber material having a predetermined hardness and elongation, even if the protruding portion of the lid portion is an undercut portion, it can be properly taken out from the mold. Therefore, the manufacturing cost of the check valve can be kept sufficiently low. In the present invention, the hardness of the silicone rubber means a value measured according to JIS K6249, and the elongation means a value measured according to JIS K7127.

  In the check valve of the present invention, from the viewpoint of simplifying the manufacturing process, it is preferable that one opening of the main body portion is constituted by a linear portion forming a hinge portion and an arc-shaped portion. Here, “arc” means a part of a circle or a part of an ellipse.

In the check valve according to the present invention, from the viewpoint that the cover portion is prevented from entering into the through hole of the main body more reliably, arcuate portion of the outer diameter R ₁ is the opening of the arcuate portion of the lid portion greater than the diameter _{R 2} of, and the difference between the _{R 1} and _{R 2} are 0.06Mm～0.50Mm. In this check valve, the angle formed between the side surface of the lid portion and the inner surface of the main body portion is more preferably 15 to 25 °. If the rubber material has a hardness of 30 to 80 degrees and an elongation of 200 to 900%, it is easy to obtain a check valve with sufficient mechanical strength without causing problems due to undercut in the manufacturing process. This is further preferable.

  The container which concerns on this invention is equipped with the container main body which consists of films, and the said non-return valve with which the container main body was mounted | worn. Since this container is provided with the above-described check valve, even if an impact is applied to the container, air can be sufficiently prevented from entering the container. Thereby, it can fully suppress that the contents deteriorate by oxidation. Moreover, since the excellent discharge property of the contents can be stably maintained by the action of the check valve, it can be used for a sufficiently long time without any special work by the user.

  The container according to the present invention preferably further includes a spout loaded with a check valve. In this case, it is also preferable that the liquid discharge port at the tip of the spout has a shape that is once narrowed in the middle and further widened.

  Further, in the container according to the present invention, at least a part of the main body of the check valve is deformed according to the difference from the atmospheric pressure when the inside of the check valve becomes negative pressure, and the check valve It is preferable to be formed thin enough to reduce the volume. When the container is changed from the discharged state to the upright state, the liquid returning to the lower part of the container generates a negative pressure in the upper part of the container. When the negative pressure acts in this manner, the main body portion of the check valve is deformed so as to be recessed by an amount corresponding to the difference from the atmospheric pressure. Then, as the check valve is deformed, the space from the check valve to the tip of the liquid discharge port in the spout becomes negative pressure, so the liquid remaining at the tip of the liquid discharge port is deformed integral of the check valve. Only suck back (return to the container side). After the suckback, even if the cap is attached, liquid does not adhere to the periphery of the liquid discharge port, so that dripping does not occur.

  In the above container, it is preferable that the main body portion of the check valve has a stepped shape including a small diameter portion and a large diameter portion, and one opening is formed in the small diameter portion.

  Furthermore, in the above container, it is also preferable that the small diameter portion is formed thinner than the large diameter portion.

  The present invention provides a method for manufacturing the check valve. That is, the check valve manufacturing method according to the present invention includes a cylindrical main body having openings at both ends, a lid disposed so as to close one opening of the main body, and the main body and the lid. And a hinge portion for opening one opening when a force is applied to the lid portion from the main body side toward the outside, and the lid portion has a peripheral edge portion of the one opening of the main body portion. A method for manufacturing a check valve having a projecting portion on its side surface, and a rubber material having a hardness of 30 to 80 degrees and an elongation of 200 to 900% in a cavity having a recess for forming the projecting portion A molding step for obtaining a molded body comprising: a mold releasing step for taking out the molded body from the cavity; and a cutting step for separating the main body portion and the lid portion while leaving a portion to be a hinge portion.

  According to the above manufacturing method, the hardness of the rubber material is 30 to 80 degrees and the elongation is 200 to 900%, thereby sufficiently preventing the portion that becomes the protruding portion of the lid portion from being caught in the concave portion of the cavity. The molded product can be smoothly taken out from the mold. For this reason, it is not necessary to use a special metal mold, and the manufacturing cost can be kept sufficiently low.

  By using the check valve according to the present invention, it is possible to sufficiently suppress the mixing of air into the container even when an impact is applied to the container and to stably maintain the excellent discharge property of the contents. . Moreover, according to the check valve manufacturing method according to the present invention, the check valve having the above-described effects can be manufactured sufficiently efficiently and at low cost.

1 is a perspective view showing a preferred embodiment of a check valve according to the present invention. (A) And (b) is the top view and sectional drawing of a non-return valve shown in FIG. It is sectional drawing which shows the state which the cover part of the non-return valve shown in FIG. 1 opened. It is a fragmentary sectional view which expands and shows the cover part vicinity of the non-return valve shown in FIG. It is a perspective view which shows the flexible vacuum vessel provided with the non-return valve shown in FIG. (A) And (b) is the perspective view and sectional drawing of the exterior body which incorporated the non-return valve shown in FIG. It is a fragmentary sectional view showing other embodiments of a check valve concerning the present invention. 6 is a cross-sectional view showing a check valve according to Comparative Example 1. FIG. It is sectional drawing of the exterior body (spout) with which the check valve and this check valve were loaded which show other embodiment of this invention. It is sectional drawing of a non-return valve. It is sectional drawing of the non-return valve in the state which a part of main body deform | transformed. It is sectional drawing which expands and shows the liquid discharge port of an exterior body (spout).

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted.

<Check valve>
With reference to FIGS. 1 to 4, an example of a check valve incorporated in a container for containing household soy sauce will be described. The check valve 10 according to the present embodiment is made of an elastomer such as a rubber material and is manufactured, for example, by integral molding. As shown in FIGS. 1 and 2, the check valve 10 includes a cylindrical main body portion 1 having openings 1 a and 1 b at both ends, and a lid portion 3 arranged so as to close the opening 1 a on the distal end side of the main body portion 1. The hinge part 5 which connects the main-body part 1 and the cover part 3 is provided. As shown in FIG. 3, the hinge portion 5 has a function of a hinge of the lid portion 3, and when a force F is applied to the lid portion 3 from the main body portion 1 side toward the outside, It has the flexibility to open the opening 1a.

  The main body 1 has a through hole 1c penetrating in the longitudinal direction, and the openings 1a and 1b form both ends of the through hole 1c. From the viewpoint of the dischargeability and ease of use of soy sauce, the inner diameter of the through hole 1c is preferably about 5.0 to 7.0 mm. As shown in FIG. 1, the lower portion of the main body 1 is thick and the upper portion is thin. The outer diameter of the lower part (thick part) of the main body 1 is preferably about 12.8 mm, and the outer diameter of the upper part (thin part) is preferably about 7.7 to 10.0 mm.

  As shown in FIG. 1, a part of the outer surface of the lower part of the main body 1 is a flat surface 1d, and a protrusion 1e is provided on the flat surface 1d. The protrusion 1e functions as a positioning mark when the check valve 10 is fixed to the exterior body 32 (see FIG. 6).

  As shown in FIG. 1, the opening 1 a on the distal end side of the main body 1 is composed of a linear portion L and an arc-shaped portion R. The linear portion L of the opening 1 a is formed by a raised portion 1 f provided in the vicinity of the opening 1 a in the through hole 1 c of the main body 1, and the linear portion L and the linear portion of the lid portion 3 are continuous. The hinge part 5 is comprised by doing. There is an advantage that the manufacturing process can be simplified by making the part other than the part constituting the hinge part into an arc shape. That is, after integral molding, the lid 3 can be separated from the main body 1 while leaving the hinge 5 by a simple method of pressurizing the inside of the main body 1.

  The lid 3 is connected to the main body 1 via the hinge 5 and is disposed so as to close the opening 1 a of the main body 1. The lid portion 3 has a protruding portion 3 a on the side surface 3 b that contacts the peripheral edge portion of the opening 1 a of the main body portion 1. By providing the protruding portion 3a on the side surface 3b of the lid portion 3, even if an impact is applied to the check valve 10, the lid portion 3 is difficult to enter the through hole 1c of the main body portion 1, and the lid portion 3 The function can be demonstrated stably. In addition, when the hinge part 5 side is made into the base end side and the opposite side is made into the front end side in the cover part 3, it is preferable to provide the protrusion part 3a in the front end side.

  The height of the protrusion 3a (the length from the side surface 3b of the lid 3 to the tip of the protrusion 3a) is preferably 0.4 to 0.6 mm, more preferably 0.45 to 0.55 mm. . If the height of the protruding portion 3a is less than 0.35 mm, the effect of preventing the lid portion 3 from entering the through-hole 1c tends to be insufficient, and if it exceeds 1.0 mm, problems due to undercuts tend to occur in the manufacturing process. .

From the viewpoint of the lid 3 is prevented from entering the through hole 1c of the main body 1 more reliably, the outer diameter R ₁ of the arcuate portion of the lid 3 than the diameter R ₂ of arcuate portions R of the opening 1a Is also preferably large. The difference between R ₁ and R ₂ is preferably 0.06 mm to 0.50 mm, and more preferably 0.08 mm to 0.25 mm. By being larger than 0.06 mm, even when an impact is applied to the container due to dropping or the like, the lid portion is difficult to enter into the through hole of the main body portion, so that pouring is not hindered. By being smaller than 0.50 mm, since the lid portion and the main body portion are hardly pseudo-adhered, the dispensing is not hindered. Incidentally, when the outside diameter of the lid portion is not constant, for example, when the side surface of the lid portion 3 is tapered as shown in FIG. 2 (b), the maximum outer diameter is R _1.

  The side surface 3b of the lid 3 has a smaller outer diameter from the upper side toward the main body 1 so that the hinge 5 can be formed and the main body 1 and the lid 3 can be efficiently separated in the manufacturing process. A taper is preferred. The angle formed between the side surface 3b of the lid 3 and the inner surface of the main body 1 (angle α shown in FIG. 4) is preferably 15 to 25 °. If the angle is greater than 15 °, the lid portion is unlikely to enter the through hole of the main body portion, so that the pouring is not hindered. When the angle is smaller than 25 °, the check valve function is more likely to be exhibited, and air mixing is less likely to occur.

  Moreover, it is also preferable that the unevenness | corrugation is provided to one or both of the contact parts of the main-body part 1 and the cover part 3 of the non-return valve 10. When the unevenness is provided, the surface tension can be lowered, thereby preventing the main body portion 1 and the lid portion 3 from adhering due to the surface tension of the content liquid and making the valve easy to open. As a method for imparting unevenness, addition of a filler to a rubber material, more specifically, a rubber material in which a filler is kneaded is used for one or both of the main body portion 1 and the lid portion 3 of the check valve 10. Can be used. As filler, calcined silica fine powder, titanium oxide powder, alumina powder, ground quartz, ground cristobalite, diatomaceous earth powder, aluminosilicate powder, magnesium oxide powder, aluminum hydroxide powder, iron oxide powder, zinc oxide powder, Heavy calcium carbonate powder is mentioned. The content of the filler in the rubber material is preferably 1 to 50% by weight, and more preferably 5 to 40% by weight. The average particle size of the filler is preferably 0.1 to 50 μm, more preferably 5 to 40 μm.

  The check valve 10 is made of a rubber material and is manufactured by integral molding. Specific examples of the rubber material include silicone rubber and NBR. When the check valve is used in a food container, it is preferable to employ silicone rubber as the rubber material.

  The hardness of the rubber material constituting the check valve 10 is 30 to 80 degrees, preferably 40 to 70 degrees, and more preferably 50 to 60 degrees. The elongation of the rubber material is 200 to 900%, preferably 300 to 800%, more preferably 400 to 700%. If the hardness of the rubber material is less than 30 degrees or the elongation exceeds 900%, the mechanical strength of the check valve 10 becomes insufficient, while the hardness of the rubber material exceeds 80 degrees or the elongation is less than 200%. In the manufacturing process, problems due to undercuts occur.

<Production method of check valve>
The manufacturing method of the check valve 10 includes (a) a molding step, (b) a cutting step, and (c) a cutting step.

(A) Molding step This step is for obtaining a molded body made of a rubber material having a hardness of 30 to 80 degrees and an elongation of 200 to 900% in a cavity having a recess for forming the protruding portion 3a. belongs to. When the raw material is cured by applying heat or pressure in the cavity, the processing conditions are set so that the hardness and elongation of the molded body are in the above ranges.

(B) Mold release process This process is for taking out the molded body from the cavity. For example, the molded body is taken out from the cavity by pulling the female mold and the male mold in opposite directions along the longitudinal direction of the molded body. In this embodiment, although the part used as the protrusion part 3a of the non-return valve 10 becomes an undercut, since the rubber material which makes a molded object has the hardness and elongation of the said range, the malfunction resulting from the part of an undercut Can be sufficiently suppressed.

(C) Cutting process This process is for cutting off the main body 1 and the lid 3 while leaving a portion to be the hinge 5. Since the opening 1a of the main body 1 is composed of a linear portion L and an arc-shaped portion R, when air is supplied to the inside of the molded body to pressurize the inside, stress concentrates on the arc-shaped portion R. Thus, only the arc-shaped portion R can be cut.

<Flexible vacuum vessel with check valve>
Next, a flexible vacuum vessel 30 that is self-supporting and easy to transport will be described with reference to FIG. The container 30 includes a container body 31 made of a transparent film having flexibility, an exterior body 32 provided obliquely on a shoulder portion of the container body 31, and a check valve 10 in which the exterior body 32 is built. . In the check valve 10, the lid portion 3 is positioned on the distal end side of the exterior body 32, and the hinge portion 5 is in the horizontal direction when the container 30 is stood in a state where the bottom portion of the container 30 is down (state shown in FIG. 5). It is built in such a way that the protruding portion 3a is positioned below the hinge portion 5 and extending.

  The film constituting the container body 31 may be a single layer, but is preferably composed of a plurality of layers. When the film is composed of a plurality of layers, for example, it is composed of a base material layer that forms an outer layer when processed into a bag shape, a sealant layer that forms an inner layer, and an adhesive layer that bonds the base material layer and the sealant layer together. Is done.

  The exterior body 32 includes a cap attachment portion 32a, a check valve fixing portion 32b provided in the lower portion thereof, and a joint portion 32c provided in the lower portion thereof. Note that the cap is not shown in FIG. The outer peripheral surface of the joint portion 32 c and the peripheral edge portion of the container main body 31 are bonded together, and the cap attaching portion 32 a and the check valve fixing portion 32 b are attached so as to protrude out of the container main body 31. As the exterior body 32, one produced by an injection molding method or the like can be used. Examples of the material of the exterior body 32 include synthetic resins such as polyethylene and polypropylene. The welding of the container body 31 and the joint portion 32c can be performed by heat sealing, high frequency sealing, hot air sealing, microwave heating, ultrasonic sealing, or the like.

  When the container 30 containing the soy sauce is tilted, a force directed from the inside to the outside is applied to the lid portion 3 of the check valve 10, and the lid portion 3 opens to the outside to discharge the soy sauce. When the container 30 is returned to the original orientation, the inside of the container 30 becomes negative pressure, and a force directed from the outside to the inside is applied to the lid portion 3. As a result, the opening 1 a of the check valve 10 is blocked and air is prevented from entering the container 30.

  Since the container 30 includes the check valve 10, even when an impact is applied to the container 30, air can be sufficiently prevented from entering the container 30. Thereby, it can fully suppress that soy sauce deteriorates by oxidation. Moreover, since the excellent discharge property of the contents can be stably maintained by the action of the check valve 10, it can be used for a sufficiently long time without any special work by the user.

  The preferred embodiment of the present invention has been described in detail above, but the present invention is not limited to the above embodiment. For example, in the said embodiment, although the case where the partial protrusion part 3a was provided in the side surface 3b of the cover part 3 was shown in FIG. 7, the whole side surface 13b of the cover part 13 becomes a taper shape. Further, the upper portion may form the protruding portion 13a. In this case, the protruding portion 13a becomes an undercut portion. However, similarly to the above-described embodiment, by using a rubber material having the hardness and elongation in the above range, problems caused by the undercut portion can be sufficiently obtained. Can be prevented.

  Further, the shape of the main body portion of the check valve is not limited to a cylinder, and may be a cylindrical shape whose cross-sectional shape is an ellipse, a rectangle, or a polygon. Furthermore, the channel cross section of the through-hole 1c and the shape of the lid are not limited to a substantially circular shape, and may be an ellipse, a rectangle, or a polygon.

  Moreover, in the said embodiment, although the non-return valve used for the container for soy sauce was demonstrated, the use of the non-return valve and the container of this invention is not limited to soy sauce, The non-return valve of this invention You may fill a container provided with liquids, such as a soft drink, an alcoholic beverage, salad oil, or a liquid detergent.

<Suckback mechanism>
Hereinafter, as another embodiment of the present invention, a container 30 having a suck back mechanism will be described (see FIGS. 9 to 12).

  In the container 30 according to the present embodiment, the liquid discharge port 32d formed at the tip of the exterior body (hereinafter also referred to as spout) 32 has a shape excellent in drainage of liquid such as soy sauce, for example, once constricted in the middle. The shape is widened first (see FIG. 9). However, when the container 30 is tilted to discharge a necessary amount of soy sauce and the container 30 is returned to the upright state, a part of the soy sauce remains in the liquid discharge port 32d, and the liquid dripping and dirt thereafter. It may cause. In consideration of such points, in this embodiment, the container 30 is provided with a suck back mechanism.

  That is, in this container 30, at least a part of the main body 1 of the check valve 10 is deformed according to the difference from the atmospheric pressure when the inside of the check valve 10 becomes negative pressure, and the reverse It is formed thin enough to reduce the volume of the stop valve 10 (see FIG. 10 and the like). In this case, the thinly formed portion is not particularly limited, but in the present embodiment, the main body portion 1 has a stepped shape including the small diameter portion 11 and the large diameter portion 12, and the small diameter portion 11 is acceptable. A check valve 10 formed of a peripheral wall thinner than the large-diameter portion 12 is used so as to have flexibility (see FIG. 11 and the like).

  The operation of the suck back mechanism in such a container 30 is as follows. First, when the container 30 is returned from an inclined discharge state to an upright (upright) state, the discharge of soy sauce stops. When the erect state is restored, the lid 3 of the check valve 10 naturally closes due to the elasticity of the elastomer, and the space from the lid 3 of the check valve 10 to the liquid discharge port 32d in the spout 32 (in FIG. 9). , And a space (indicated by reference symbol B in FIG. 9) inside the container 30 relative to the lid portion 3 of the check valve 10 is blocked. At this time, with the soy sauce remaining at the tip of the liquid discharge port 32d (see FIG. 12), when a cap (not shown) is attached to the cap mounting portion 32a of the spout 32, the remaining soy sauce is around the liquid discharge port 32d. It may adhere to and cause dripping.

  In this regard, in the present embodiment, when the container 30 is changed from the discharged state to the upright state, the soy sauce that is going to return to the lower portion of the container 30 is subjected to a negative pressure (indicated by symbol P in FIG. Cause it to occur. When negative pressure acts in this manner, a part of the main body portion 1 of the check valve 10 (in the case of the present embodiment, the peripheral wall of the small diameter portion 11) is deformed so as to be recessed by an amount corresponding to the difference from the atmospheric pressure ( FIG. 11). Then, as the check valve 10 is partially deformed, the space A in the spout 32 (the space from the lid 3 of the check valve 10 to the liquid discharge port 32d) becomes negative pressure, so the tip of the liquid discharge port 32d The soy sauce remaining in the container sucks back only the deformed body integral of the check valve 10 (see FIG. 12). After the suckback, even if the cap is attached, the soy sauce does not adhere to the periphery of the liquid discharge port 32d, so that no dripping occurs. In addition, although it is assumed that the time required for the user to put on the cap after returning the container 30 in the discharged state to the upright state is 1 to 2 seconds at the earliest, It is sufficient time to suck back the soy sauce remaining in the liquid discharge port 32d in the container 30.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

(Production of molded bodies of Examples 1 to 3)
In order to produce check valves having the configuration shown in FIG. 1 and the dimensions shown in Examples 1 to 3 of Table 1, molded articles were produced as follows. That is, after a silicone rubber raw material was placed in the cavity, the raw material was cured at 175 ° C. for 6 minutes in a cavity constituted by two molds to obtain a molded body. After the molded body was taken out, the protrusion was observed with a microscope, and no damage was observed. The silicone rubber constituting the molded bodies according to Examples 1 to 3 had a hardness of 55 degrees and an elongation of 380%.

(Production of molded bodies of Examples 4 and 5)
In order to produce check valves having the configuration shown in FIG. 1 and the dimensions shown in Examples 4 and 5 of Table 2, molded articles were produced as follows. That is, after a silicone rubber raw material was placed in the cavity, the raw material was cured at 170 ° C. for 135 seconds in a cavity constituted by nine molds to obtain a molded body. After the molded body was taken out, the protrusion was observed with a microscope, and no damage was observed. All of the silicone rubbers constituting the molded bodies according to Examples 4 and 5 had a hardness of 60 degrees and an elongation of 350%.

(Preparation of the molded body of Comparative Example 1)
In order to produce a check valve having the configuration shown in FIG. 8 and the dimensions shown in Comparative Example 1 of Table 2, a silicone rubber raw material was poured into a cavity constituted by one mold, and Examples 1 to 3 The raw material was cured in the same manner. Thereby, the molded object without a protrusion part in a cover part was produced. The silicone rubber constituting the molded body according to Comparative Example 1 had a hardness of 55 degrees and an elongation of 380%.

[Production of check valves of Examples 1 to 5 and Comparative Example 1]
The inside of the obtained molded body was pressurized, and portions other than the linear portion serving as the hinge portion were cut into an arc shape, and check valves of Examples 1 to 5 and Comparative Example 1 were produced. In any of the check valves of Examples 1 to 5 and Comparative Example 1, the angle α formed by the side surface of the lid portion and the inner surface of the main body portion was 20 °.

[Production of flexible vacuum vessel]
The check valves of Examples 1 to 5 and Comparative Example 1 were mounted in the exterior body, and the exterior body and the container body were welded to produce a container having the configuration shown in FIG. Note that a laminated film made of PET / ON / L-LDPE was used as the flexible film forming the container body.

[Evaluation test]
Samples were prepared by filling the containers according to Examples 1 to 5 and Comparative Example 1 with 500 ml of soy sauce, and the following drop test was performed. After the specimen was naturally dropped from the drop heights shown in Tables 1 and 2, the presence or absence of air mixing (Air mixing) into the container and the dischargeability of soy sauce were evaluated. In addition, the presence or absence of air mixing was judged by visual observation, and whether the dischargeability of soy sauce was good or bad was judged by whether or not the soy sauce was smoothly produced when the container was tilted by about 45 °. Tables 1 and 2 show the results.

  Next, a plurality of containers according to Example 1 were prepared and filled with 500 ml of soy sauce to prepare specimens. The performance of the check valve was evaluated in more detail by performing the following test on the specimen.

(Standing test)
The container containing the soy sauce was stored at room temperature, and after 12, 24, 36, 48 and 120 hours, the presence or absence of air in the container and the discharge of the soy sauce were confirmed. Five specimens were tested under each condition. Table 3 shows the results.

  After 12, 24, 36, and 48 hours, no air was mixed in all the specimens. Moreover, the dischargeability was good. After 120 hours (5 days), no air was mixed in, but even if the soy sauce was slightly solidified at the part where the lid and the peripheral edge of the opening of the main body were in contact (seal part) and the container was tilted Soy sauce was not discharged spontaneously.

(Drop test I)
Under the conditions (i) and (ii) below, the container containing the soy sauce was dropped. The height at which the container was dropped was changed, and the presence or absence of air in the container after dropping and the dischargeability of soy sauce were confirmed. The presence / absence of air mixing and the evaluation criteria for the discharge of soy sauce are as described above. Five specimens were tested under each condition.
(I) Without attaching a cap to the cap attachment portion of the outer package, the container was naturally dropped once with the bottom portion of the container body down. Table 4 shows the results.
(Ii) A cap was attached to the cap attachment portion of the outer package, and the container was naturally dropped once with the bottom of the container body down, and then once with the side of the container body down. Table 5 shows the results.

  Regardless of whether a cap was attached or not, no air was mixed in all samples up to a drop height of 140 cm. Moreover, the dischargeability was good. On the other hand, at a drop height of 160 cm, the check valve lid portion entered and air contamination occurred. And since the lid part of the check valve entered, the soy sauce was not spontaneously discharged even if the container was tilted. In addition, the leakage of the contents was not observed in each test up to a drop height of 160 cm.

(Drop test II)
For a container without a cap attached to the cap attachment part of the outer package, the fall height is fixed to 120 cm, the number of drops is 5 or 10, and the container is allowed to fall naturally with the bottom of the container body down. It was. Table 6 shows the results. Two specimens were tested under each condition.

  In five consecutive drops, no air was mixed in all specimens. Moreover, the dischargeability was good. On the other hand, in the case of 10 consecutive drops, the check valve lid portion entered and air contamination occurred. And since the lid part of the check valve entered, the soy sauce was not spontaneously discharged even if the container was tilted.

DESCRIPTION OF SYMBOLS 1 ... Main-body part, 1a, 1b ... Opening, 3,13 ... Cover part, 3a, 13a ... Projection part, 3b, 13b ... Side surface, 5 ... Hinge part, 10 ... Check valve, 11 ... Small diameter part, 12 ... Large Diameter: 30 ... Flexible vacuum vessel (container), 31 ... Container body, 32 ... Exterior body (spout), 32d ... Liquid discharge port, F ... Force, L ... Linear portion, P ... Negative pressure, R ... Arc shape portion.

Claims (12)

A check valve made of a rubber material and manufactured by integral molding,
A cylindrical main body having openings at both ends;
A lid portion arranged to close one opening of the main body portion;
A hinge portion for connecting the body portion and the lid portion and opening the one opening when a force is applied to the lid portion from the body portion side toward the outside;
With
The said cover part is a check valve which has the protrusion part which contact | abuts the peripheral part of said one opening of the said main-body part in the side surface.   2. The check valve according to claim 1, wherein the one opening is configured by a linear portion forming the hinge portion and an arc-shaped portion. The reverse diameter according to claim 2, wherein an outer diameter R ₁ of the arc-shaped portion of the lid portion is larger than a diameter R ₂ of the arc-shaped portion of the opening, and a difference between R ₁ and R ₂ is 0.06 mm to 0.50 mm. Stop valve.   The check valve according to claim 3, wherein an angle formed between a side surface of the lid portion and an inner surface of the main body portion is 15 to 25 °.   The check valve according to claim 4, wherein the rubber material has a hardness of 30 to 80 degrees and an elongation of 200 to 900%. A container body made of a film;
The check valve according to any one of claims 1 to 5, which is attached to the container body;
Container.   The container of claim 6, further comprising a spout loaded with the check valve.   The container according to claim 7, wherein the liquid outlet at the tip of the spout has a shape that once narrows in the middle and further spreads further.   At least a part of the main body of the check valve is formed thin enough to reduce the volume of the check valve by deforming according to the difference from atmospheric pressure when the inside of the check valve becomes negative pressure The container according to claim 8.   The container according to claim 9, wherein the main body portion of the check valve has a stepped shape including a small diameter portion and a large diameter portion, and the one opening is formed in the small diameter portion.   The container according to claim 10, wherein the small diameter portion is formed thinner than the large diameter portion. A cylindrical main body having openings at both ends, a lid disposed so as to close one opening of the main body, and the main body and the lid are connected to the lid. A hinge portion for opening the one opening when a force is applied outward from the main body portion side, and a protrusion that the lid portion contacts with a peripheral edge portion of the one opening of the main body portion. A check valve manufacturing method on a side surface;
A molding step of obtaining a molded body made of a rubber material having a hardness of 30 to 80 degrees and an elongation of 200 to 900% in a cavity having a recess for forming the protruding portion;
A mold release step of taking out the molded body from the cavity, and a cutting step of separating the main body portion and the lid portion leaving a portion to be the hinge portion;
A check valve manufacturing method comprising:

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