JP4301357B2 - A tube, a tube molded product, and a method of manufacturing the tube. - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tube having an axial vertical stripe on an outer surface, a tube molded product using the tube, and a method for manufacturing the tube.
[0002]
[Prior art]
Conventionally, tube containers are often used for storing pasty products such as pasty drugs, quasi drugs, cosmetics, and industrial products. By forming the torso so as to be squeezable, an appropriate amount of content can be easily taken out, and as described in Patent Document 1, depending on the nature of the content, usage form such as long-term storage, for example, A tube container having an outer layer and an inner layer made of polyethylene, an intermediate layer made of an oxygen barrier resin, and a wall laminated structure is used.
[0003]
In many cases, a single-layer tube or a laminated tube obtained by extruding a synthetic resin into a cylindrical shape is used for the tube body of the tube container.
[0004]
In the case of a laminated tube, several types of molten resin flow paths are separately provided in the mold, and a co-extrusion molding method using a molding die in which the flow paths are merged in the mold, or the outer diameter of the tube-shaped substrate layer There is a method in which another layer is extruded from a large die into a pipe shape, and this is adhered to the base material layer by vacuum suction from the nipple side of the die outlet to uniformly coat the other layer.
[0005]
Also, as described in Patent Document 1, for example, the tube is cut to a predetermined length, and a head composed of a shoulder and a mouth is attached to one open end by injection molding or compression molding, and the contents are further added. After filling, the other open end is sealed with a heat seal or the like and used as a tube container product.
[0006]
[Patent Document 1]
JP 2003-54589 A
[Problems to be solved by the invention]
However, tube forming is basically a method of extruding a synthetic resin into a cylindrical shape, and it provides functions such as making the contents of the tube container identifiable on the outer surface of the tube only with a decorative or tactile sensation. It is difficult to form irregularities for the purpose, and even if realized, there are problems in terms of productivity and cost.
[0008]
Even when forming a laminated tube with other layers laminated on the outer surface of the tube, to maintain a certain level of uniformity in order to achieve a high-class feel in addition to the aesthetic appearance. Therefore, it is necessary to form unevenness.
[0009]
Therefore, the present invention has a technical problem of forming a vertical strip maintaining a certain degree of uniformity on the outer surface of the tube while ensuring high productivity. It is an object of the present invention to provide a laminated tube and a tube molded product having functionality such that identification is possible.
[0010]
[Means for Solving the Problems]
Among the present invention for solving the above technical problems, the means of the invention according to claim 1 is based on a molding method in which a longitudinal belt-shaped synthetic resin layer mixed with a foaming agent is co-extruded with at least one cylindrical synthetic resin layer. Being a thing,
The longitudinal strips in the axial direction are formed on the outer surface by the foamed layer formed on the cylindrical synthetic resin layer by foaming of the vertical strip-shaped synthetic resin layer accompanying the coextrusion molding .
[0011]
According to the above configuration of the first aspect, vertical stripes are formed on the outer surface of the tube by the vertical band-shaped foam layer, the decorativeness and appearance of the tube are improved, and the tube surface can be used only by tactile sensation due to the unevenness of the tube surface. It becomes possible to distinguish from the tube. Here, the foam layer does not necessarily need to be positioned in the outermost layer, and if it is positioned at least in the intermediate layer, the strips can be formed in the outer layer by increasing the thickness of the foam layer.
[0012]
In addition, the tube can be easily crushed along the vertical stripe, and the contents stored in a tube molded product such as a tube container formed from this tube can be easily extruded. It functions as an aggregate of the tube, and the shape of the tube can be stably maintained.
[0013]
The means of the invention described in claim 2 is that, in the invention described in claim 1, it has a cylindrical outer layer and an inner layer, and an intermediate layer has a vertical belt-like foam layer.
[0014]
According to the above configuration of the second aspect, the longitudinal strip can be formed on the outer surface of the laminated tube having the inner layer and the outer layer by the longitudinal strip-like foam layer of the intermediate layer, and the entire outer surface is formed by the outer layer of the cylindrical strip. Longitudinal stripes can be formed on the outer surface while maintaining constant uniformity on the outer surface. Further, the entire inner surface of the tube can be formed almost smoothly by the inner layer, and the same contents as those of a normal tube can be obtained with respect to the storage capacity of the contents when used for a tube container or the like.
[0015]
The resins forming the outer layer, the inner layer and the foamed layer can be different types of synthetic resins depending on the purpose, and can also be the same type or the same type of synthetic resins.
[0016]
The means of the invention described in claim 3 is that, in the invention described in claim 1 or 2, a plurality of vertical stripes are provided.
[0017]
According to the above-described configuration of the third aspect, a plurality of vertical stripes are formed in a stripe shape on the tube, the decorativeness of the tube is further improved, and the number of the vertical stripes is determined so that only the tactile sensation is obtained. Tubes can be individually identified.
[0018]
According to a fourth aspect of the present invention, in the invention of the third aspect, the longitudinal stripes are provided symmetrically.
[0019]
According to the above-described configuration, since the vertical stripes are provided symmetrically about the axis, the tube can be flattened along the axially symmetrical vertical stripe, and the tube bottom is sealed to seal the tube container It is convenient when forming a tube molded product such as. Further, when taking out the stored item from the tube molded product formed from the tube, there is an advantage that the vertical strip serves as a guide to easily crush the tube molded product and to easily push out the stored product.
[0020]
According to a fifth aspect of the present invention, in the tube according to the third or fourth aspect, the vertical stripes have different widths.
[0021]
According to the above-described configuration, since the vertical stripes have different widths, it is possible to improve the fun of appearance, and it is possible to print characters or the like on wide vertical stripes, and further due to the difference in width. An identification function can be provided.
[0022]
According to a sixth aspect of the present invention, in the first, second, third, fourth, or fifth aspect of the invention, a cylindrical layer formed of an aluminum laminate material is provided.
[0023]
According to the above configuration of the sixth aspect, a tube (laminated tube) having good properties of an aluminum laminate material such as oxygen barrier property and excellent in the modification property and functionality by the vertical stripe formed on the outer surface is provided.
[0024]
According to a seventh aspect of the present invention, there is provided the invention according to the first, second, third, fourth, fifth or sixth aspect, wherein the cylindrical layer and the foamed layer have different colors.
[0025]
According to the above-described configuration of the seventh aspect, for example, a striped pattern having different colors can be formed on the outer surface of the tube by making the foam layer different color, and the decorativeness can be improved by the color.
[0026]
Further, for example, even when the outer layer and the inner layer are provided and the foamed layer is an intermediate layer, the decorativeness due to the color can be exhibited by making the outer layer transparent or translucent.
[0027]
According to an eighth aspect of the present invention, the tube according to the first, second, third, fourth, fifth, sixth or seventh aspect is cut into a predetermined length, and one open end is crushed into a flat shape and closed. The other open end is provided with a head composed of a shoulder and a mouth to form a tube molded product.
[0028]
According to a ninth aspect of the present invention, the tube according to the first, second, third, fourth, fifth, sixth or seventh aspect is cut into a predetermined length, and both open ends are crushed flatly to be closed. To make a tube molded product.
[0029]
According to the above-described configuration according to claim 8 or 9, a tube molded product having high designability and functionality can be provided using a tube in which decorativeness and functionality are taken into account by forming a vertical shape.
[0030]
The method for producing a laminated tube of the invention according to claim 10 coextrudes a longitudinal synthetic resin layer mixed with 0.1 to 10% by weight of a foaming agent together with a cylindrical synthetic resin layer,
By forming a longitudinal strip-like foam layer on the cylindrical synthetic resin layer by foaming of the longitudinal strip-like synthetic resin layer accompanying coextrusion,
This foam layer is to form an axial longitudinal strip on the outer surface.
[0031]
According to the manufacturing method of claim 10, since the longitudinal strip-shaped synthetic resin layer mixed with the foaming agent in the multilayer die for extrusion is coextruded to the outside in a state of being joined to the cylindrical synthetic resin layer, the cylindrical synthetic resin layer A vertical belt-like layer containing a foaming agent can be stably formed on the tube, and a tube having a uniform shape of vertical stripes can be obtained.
[0032]
If the amount of the foaming agent is less than 0.1% by weight, foaming is insufficient, and if it exceeds 10% by weight, it is difficult to control foaming and it becomes difficult to obtain a certain vertical shape and formability. Productivity will be lowered due to defects.
[0033]
The manufacturing method of the tube of the invention of claim 11 is the manufacturing method of claim 10, wherein the cylindrical synthetic resin layer forming the outer layer, the cylindrical synthetic resin layer forming the inner layer, and between the outer layer and the inner layer And coextruding the longitudinal belt-shaped synthetic resin layer.
[0034]
The production according to claim 11, wherein generally forming a vertical strip-shaped synthetic resin layer containing a foaming agent into a certain shape results in low-productivity molding because of the foaming behavior of the resin layer and the vertical strip shape. By the method, the longitudinal strip synthetic resin layer can be joined between the outer layer and the inner layer in the multilayer die for extrusion, so that it can be stably co-extruded while keeping the shape constant, and the entire outer surface is formed by the outer layer. Therefore, it is possible to obtain a tube in which vertical stripes having a uniform appearance and properties are formed.
[0035]
In addition, it is possible to form vertical stripes by foaming the vertical belt-shaped synthetic resin layer without forming irregularities in the resin passage at the tip of the die, the die structure can be simplified, and coextrusion can be achieved smoothly, Productivity will be high.
[0036]
A method for manufacturing a tube according to a twelfth aspect of the present invention is the method of manufacturing a tube according to the tenth or eleventh aspect, wherein the cylindrical synthetic resin layer and the vertical belt-shaped synthetic resin layer are coated on the cylindrical body serving as the base layer. Co-extrusion.
[0037]
According to the manufacturing method of the twelfth aspect, it is possible to form vertical stripes on the outer surface of a tube having a layer that cannot be co-extruded, such as an aluminum laminate material.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an (a) side view and (b) cross-sectional view of a tube 1 showing an embodiment of the tube of the present invention, and FIG. 2 is an enlarged view of a part of FIG. Is.
[0039]
As shown in FIG. 2, the tube 1 has a laminated structure formed of an outer layer 2, an inner layer 3, and a single longitudinal strip-shaped foam layer 4 that is an intermediate layer, and the foam layer 4 deforms the outer layer into a convex shape. Thus, one vertical strip 5 is formed on the outer surface.
[0040]
Here, the foam layer 4 itself for forming the vertical shape 5 is not exposed on the surface, and the entire outer surface including the vertical shape 5 portion is formed of the outer layer. The appearance of the vertical shape 5 can be achieved without worrying about a decrease in aesthetics due to the exposure of the foam layer 4.
[0041]
The synthetic resin used for the outer layer 2, the inner layer 3 and the foamed layer 4 can be selected according to the purpose. However, if all the layers are made of, for example, a polyethylene-based resin, the adhesiveness between the layers can be improved. An excellent laminated tube can be obtained. Further, a gas barrier layer, an adhesive layer or the like can be added depending on the purpose.
[0042]
FIG. 3 shows an example of a tube container 9 which is a tube molded product of the present invention. The tube 1 shown in FIG. 1 is cut into a predetermined length, and a shoulder 6 and a mouth are formed at one open end. A state in which the head 8 composed of the portion 6 is melt-bonded by injection molding or compression molding is shown. Normally, after the contents are filled from the other open end, the other open end is heat-sealed in a flat shape by a heat seal method, an ultrasonic seal method or the like, and the content is sealed and used.
[0043]
As shown in FIG. 3, the tube container 9 has a single vertical strip 5 formed on the body portion, and the vertical strip 5 forms irregularities on the outer surface of the tube container 9. The decorativeness of the container 9 and the visual interest can be improved.
[0044]
Moreover, since this tube container 9 can recognize the vertical stripe 5 just by touching, the example of the tube container 9 is one in which the vertical stripe 5 is formed. By changing the number, formation position, width, etc., the tube container 9 can be identified by touch when touched by hand.
[0045]
For example, if the contents to be stored in the tube container 9 are determined according to the number of the vertical strips 5, the contents stored in the tube container 9 can be identified simply by touching the tube container 9 with a hand. This is convenient for people who have visual impairments, etc., and also for healthy people, for example, when using a plurality of tube containers 9 or the like in situations where it is difficult to see the display of contents, such as during face washing.
[0046]
FIG. 6 shows another embodiment of the tube 1 of the present invention, and the layer structure is the same as that of the embodiment shown in FIG. 1, but four vertical strips 5 are formed on the tube 1 in an axial symmetry, Two of them are close to each other. In this case, when the tube 1 is crushed, the groove 5a sandwiched between the two vertical stripes 4 protrudes outward using the vertical stripes 5 as a guide, and the tube 1 can be easily crushed flat.
[0047]
FIG. 7 shows another example of the tube container 9, and the container shape and layer structure are the same as those of the tube container shown in FIG. 3, but the vertical stripes 5 are formed at equal intervals over the entire circumference. As a result, it has a striped uneven shape, improves the decorativeness, and can easily crush the tube container 9 into a flat shape using the vertical strip 5 as a guide. Also when taking out a thing, since the tube container 9 can be crushed by using the vertical strip 5 as a guide, the contents can be neatly pushed out from the tube container 9 and the like, and the handleability is improved.
[0048]
Further, here, for example, if the inner layer 3 and the foamed layer 4 are made different colors and the outer layer 2 is made colorless and transparent or translucent, a color decoration is given to the surface of the body portion of the tube container 9 along with striped irregularities. can do.
[0049]
FIG. 8 shows still another example of the tube molded product, and the bag container 10 can be formed from the tube 1. The tube 1 is cut into a predetermined length, one open end of the tube 1 is flattened and closed with a heat sealing machine or an ultrasonic sealing machine, and the contents are filled from the other open end. The other open end is similarly closed and the contents are sealed and stored.
[0050]
FIG. 4 shows an embodiment of a method of manufacturing the tube 1 according to the present invention shown in FIG. 1, in which one vertical strip 5 is formed in the axial direction by the foam layer 4 of the vertical strip on the outer surface. It is a longitudinal cross-sectional view which shows the one part schematic block diagram of the coextrusion molding apparatus for doing, and FIG. 5 (a) and (b) is shown along the AA line and BB line in FIG. 4, respectively. FIG.
[0051]
As shown in FIG. 4, the coextrusion molding is an extrusion machine that supplies a molten resin that is a material of the inner layer 3 (not shown) and a molten resin in which a foam material that is the material of the foam layer 4 is mixed. And an extruder for supplying a molten resin as a material for the outer layer 2, and the molten resin is supplied from these extruders to the respective resin inlets 13 a, 14 a, and 12 a.
[0052]
First, the molten resin as the material of the inner layer 3 is supplied from the resin inlet 13a to the manifold having a function for achieving the annular flow, and the annular inner resin passage 13 forms the annular flow. The molten resin mixed with the foaming agent as the material of the foam layer 4 passes through the resin inflow port 14a, and is formed into a narrow strip shaped foam having a rectangular cross section formed at the circumferential position indicated by reference numeral 14 in FIG. It flows through the layer resin passage 14 and joins the inner layer resin passage 13.
[0053]
Further, the molten resin that becomes the material of the outer layer 2 forms an annular flow in the resin passage 12 for the outer layer through the resin inlet 12a and the manifold, and the molten resin in the form of the vertical band that becomes the material of the foamed layer 4 becomes the material of the inner layer 3. A cylindrical resin layer that forms the outer layer 2 from the die 11 and the inner layer 3 are formed by being joined to the annular flow of the molten resin that is the material of the inner layer 3 from the outside so as to be sandwiched between the molten resin. The cylindrical resin layer to be formed and the vertical belt-shaped resin layer forming the foamed layer 4 are coextruded out of the die 11 in a laminated state.
[0054]
Here, a foaming agent is mixed with the molten resin used as the material of the foam layer 4, and this foaming agent has already decomposed in the die 11, but the foaming in the die is suppressed by the pressure of the molten resin. Therefore, as shown in FIG. 5A, the laminated molten resin can maintain and maintain a smooth annular flow even after merging.
[0055]
When the laminated molten resin is pushed out from the die 11, the resin pressure rapidly decreases, and foaming in the longitudinal belt-shaped molten resin layer mixed with the foaming agent proceeds, and the thickness of the foamed layer 4 is increased. The outer layer 2 which is increased and still in a molten state is deformed in a state of pushing up from the inside, and as a result, the vertical strip 5 can be formed on the outer surface of the tube 1. (See FIG. 5 (b))
[0056]
As described above, in the manufacturing method of the present embodiment, the vertical stripes 5 are formed on the outer surface of the tube 1 by the increase in thickness due to foaming of the foam layer 4 when extruded from the die 11 to the outside. There is no need to form irregularities in the annular resin passage inside, and it is possible to form with a normal annular die for multilayer molding, and it is possible to manufacture the tube 1 having the vertical stripes 5 with high production.
[0057]
The mixing amount of the foaming agent is 0.1 to 10% by weight, more preferably 0.2 to 5% by weight. If the amount is too small, the expansion ratio is not increased and the vertical strip 5 is not sufficiently formed, and is too much. The vertical strip 5 has a certain aesthetic appearance because foaming in the die 11 occurs and coextrusion cannot be performed, the size of the foamed foam after exiting the die 11 becomes too large, and foam breakage occurs. The problem that it becomes impossible to make a certain thing occurs.
[0058]
In general, the foaming agent is mixed by preparing a so-called master batch in the form of a pellet after mixing the foaming agent with a predetermined synthetic resin at a relatively high concentration, and mixing this master batch with the resin that is the material of the foam layer 4. Implemented by
[0059]
In the embodiment of the present manufacturing method, the foamed layer 4 of the vertical strip is made one, but a plurality of resin passages are formed through the manifold from the resin inlet 14a of the molten resin mixed with the foaming agent in FIG. A plurality of foamed layers 4 can be formed at a desired position by branching into a vertical strip-shaped passage.
[0060]
Further, reference numeral 15 in FIG. 4 denotes a mandrel, which stably holds the shape of the tube 1 extruded from the forming die 11. Although not shown, in the manufacture of the tube 1, a cooling device that cools the tube 1 extruded from the molding die 11 while maintaining the shape with the mandrel 15, a tension device that pulls the extruded tube 1, and the tube 1. For example, a cutting device or the like that cuts the material into an appropriate length is provided.
[0061]
FIG. 9 shows a schematic configuration of a part of an apparatus for forming a tube 1 by co-extruding a cylindrical synthetic resin layer and a vertical strip-shaped synthetic resin layer on a cylindrical body to be a base material layer 16 in a covering form. FIG. 10A and FIG. 10B are cross-sectional views taken along lines CC and DD in FIG. 9, respectively.
[0062]
As shown in FIG. 9, this co-extrusion molding supplies an extruder that supplies a molten resin that is a material of the inner layer 3 (not shown) and a molten resin that is mixed with a foaming agent that is a material of the foam layer 4. It has an extruder, and each molten resin is supplied to the resin inflow ports 13a and 14a.
[0063]
First, the molten resin as the material of the inner layer 3 is supplied from the resin inlet 13a to the manifold having a function for achieving the annular flow, and the annular inner resin passage 13 forms the annular flow. A molten resin in which a foaming agent as a material of the foam layer 4 is mixed is formed through a resin inflow port 14a at a circumferential position indicated by reference numeral 14 in FIG. A vertical belt-like synthetic resin layer in which a foaming agent as a material of the foam layer 4 is mixed is laminated on the outer surface of the cylindrical synthetic resin forming the inner layer 3 by flowing through the resin passage 14 and joining the resin passage 13 for the inner layer. In this state, it is coextruded on the base material layer 16 of the tubular body in a covering form.
[0064]
When the resin pressure drops from the die 11, the foaming of the resin layer mixed with the foaming agent progresses, and the vertical shape 5 including the foamed layer 4 is formed on the inner layer 3. (See FIG. 10 (b))
[0065]
As the base material layer 16, for example, a flexible aluminum laminate material formed into a cylindrical shape can be used. Of course, the co-extrusion can be made into three layers of the outer layer 2, the foam layer 4 and the inner layer 3, and depending on the purpose, a gas barrier layer, an adhesive layer, etc. can be added to form a multilayer. it can.
[0066]
【The invention's effect】
Since the present invention has the above-described configuration, the following effects can be obtained.
In the first aspect of the present invention, vertical stripes are formed on the outer surface of the tube by the vertical band-shaped foam layer, and the decorativeness and appearance of the tube are improved. Tubes can be distinguished from other tubes.
[0067]
In addition, the tube can be easily crushed along the vertical strip, the contents stored in the tube molded product molded from the tube can be easily extruded, and the vertical strip functions as the aggregate of the tube body. Thus, it is possible to provide added value in terms of function, such as maintaining the shape of the tube stably.
[0068]
In the invention according to claim 2, it has a cylindrical outer layer and an inner layer, and by forming the intermediate layer as a foamed layer, a vertical strip is formed on the outer surface of the tube by the vertical band-shaped foamed layer of the intermediate layer. In addition, since the entire outer surface is formed by the outer layer, the vertical stripes can be formed while maintaining a certain uniformity of the outer surface.
[0069]
In the invention according to claim 3, by providing a plurality of vertical stripes, a plurality of vertical stripes are formed in a strip shape on the tube, and the decorativeness of the tube is further improved. By deciding the number, it is possible to identify the tubes individually only by touch.
[0070]
In the invention according to claim 4, by providing the vertical stripes symmetrically about the axis, the tube can be flattened along the axially symmetrical vertical stripe, and the bottom of the tube is sealed. This is convenient when forming tube molded products such as tube containers and bag containers.
[0071]
In addition, when taking out stored items from a tube molded product formed from a tube, the vertical strips serve as guides to easily crush the tube molded product. For example, it is easy to extrude a cream-like content having a certain viscosity. The handleability of the molded product can be improved.
[0072]
In the invention described in claim 5, by making the vertical stripes different in width, it is possible to improve the appearance of the appearance, and it is possible to print characters etc. on a wide vertical stripe, Can have an identification function based on the difference in width.
[0073]
In the invention of claim 6, by having a cylindrical layer formed from an aluminum laminate material, it has good properties of an aluminum laminate material such as oxygen barrier property, and is modified by a vertical stripe formed on the outer surface Providing tubes with excellent performance and functionality.
[0074]
In the invention of claim 7, by making the foam layer different color, for example, a striped pattern with different colors can be formed on the outer surface of the tube, and the decorativeness can be improved also by the color. it can.
[0075]
In invention of Claim 8 or 9, the tube molded article with high designability and functionality can be provided using the tube which considered the decorativeness and functionality by vertical formation.
[0076]
In the invention of claim 10, since the strip-shaped synthetic resin layer mixed with the foaming agent in the multilayer die for extrusion is extruded to the outside in a state where it is merged with the synthetic resin layer of the tube, A vertical belt-like layer containing a foaming agent can be stably formed on the layer, and a tube having a uniform shape of vertical stripes can be obtained.
[0077]
In the invention of claim 11, the longitudinal belt-shaped synthetic resin layer containing the foaming agent is merged by joining the longitudinal-band synthetic resin in which the foaming agent is mixed between the outer layer and the inner layer in the multilayer die for extrusion. Co-extrusion can be carried out more stably, and a tube having a certain level of uniformity and good appearance and formed with vertical stripes can be obtained without impairing productivity.
[0078]
In the invention of claim 12, by co-extrusion of the cylindrical synthetic resin layer and the strip-shaped synthetic resin layer on the cylindrical body serving as the base material, the co-extrusion of, for example, an aluminum laminate material can be performed. Even for a tube having a layer that cannot be formed, it is possible to easily form a vertical stripe on the outer surface.
[Brief description of the drawings]
FIG. 1A is a side view of a tube and FIG. 1B is a cross-sectional view showing an embodiment of the tube of the present invention.
FIG. 2 is a cross-sectional view showing an enlarged main part of FIG.
FIG. 3 is a side view showing an example of a tube molded product of the present invention.
FIG. 4 is an explanatory view showing an embodiment of the method for producing a tube of the present invention.
5 is a cross-sectional view taken along line (a) AA and line (b) BB in FIG. 4;
6A is a side view of a tube and FIG. 6B is a cross-sectional view showing another embodiment of the tube of the present invention.
7A is a side view showing another example of the tube-formed product of the present invention, and FIG.
FIG. 8 is a perspective view showing an example of a bag container formed from a tube, which is still another example of the tube molded product of the present invention.
FIG. 9 is an explanatory view showing another embodiment of the method for producing a laminated tube of the present invention.
10 is a cross-sectional view taken along line (a) CC and line (b) DD in FIG. 9;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Tube 2; Outer layer 3; Inner layer 4; Foamed layer 5; Vertical strip 5a; Groove 6; Shoulder part 7; Mouth part 8; Head 9; Tube container 10: Bag container 11; Die 12; Resin inlet 13; Inner layer resin passage 13a; Resin inlet 14; Foamed layer resin passage 14a; Resin inlet 15; Mandrel 16;

Claims (12)

It is based on a molding method in which a longitudinal strip-shaped synthetic resin layer mixed with a foaming agent is co-extruded together with at least one cylindrical synthetic resin layer,
A tube in which an axial vertical strip (5) is formed on the outer surface by a vertical strip-shaped foam layer (4) laminated on the cylindrical synthetic resin layer by foaming of the vertical strip-shaped synthetic resin layer accompanying the coextrusion molding . The tube according to claim 1, wherein the tube has a cylindrical outer layer (2) and an inner layer (3), and an intermediate layer has a longitudinal belt-like foam layer (4). The tube according to claim 1 or 2, wherein a plurality of vertical strips (5) are provided. 4. The tube according to claim 3, wherein the longitudinal stripes (5) are provided symmetrically about the axis. The tube according to claim 3 or 4, wherein the vertical stripes (5) have different widths. 6. A tube according to claim 1, 2, 3, 4, or 5 having a cylindrical layer formed from an aluminum laminate material. The tube according to claim 1, 2, 3, 4, 5 or 6, wherein the cylindrical layer and the foamed layer (4) have different colors. The tube according to claim 1, 2, 3, 4, 5, 6 or 7 is cut into a predetermined length, and one open end is flattened and closed, and the other open end is shouldered (6 ) And a head (8) comprising a mouth part (7). A tube molded article obtained by cutting the tube according to claim 1, 2, 3, 4, 5, 6 or 7 into a predetermined length and crushing both open ends into a flat shape. Along with the cylindrical synthetic resin layer, a longitudinal strip synthetic resin layer mixed with 0.1 to 10% by weight of a foaming agent is coextruded, and the longitudinal synthetic resin layer is foamed by the coextrusion to form a cylindrical synthetic resin layer. A method for producing a tube, in which a longitudinal strip-like foam layer (4) is formed by lamination, and an axial longitudinal strip (5) is formed on the outer surface by the foam layer (4). A cylindrical synthetic resin layer that forms the outer layer (2), a cylindrical synthetic resin layer that forms the inner layer (3), and a longitudinal belt-shaped synthetic resin layer between the outer layer (2) and the inner layer (3) are coextruded. The method for producing a tube according to claim 10. The manufacturing method of the tube of Claim 10 or 11 which coextrudes a cylindrical synthetic resin layer and a vertical strip | belt-shaped synthetic resin layer on a cylindrical body used as a base material layer (16) in a covering form.

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