How wooden straws are made

Abstract

To provide a method of more surely manufacturing wooden straws by reducing generation of defective pieces.SOLUTION: The method of manufacturing wooden straws 10 includes: a first wetting process which wets a veneer of 0.1 mm to 0.4 mm thick; a coating process for coating an adhesive on the wetted veneer; a winding process which cylindrically winds the veneer coated with the adhesive; a first drying process for drying the cylindrically wound veneer; a second wetting process for wetting the dried cylindrical veneer; a cutting process for cutting both ends of the wetted cylindrical veneer; and a second drying process for drying the cylindrical veneer whose both ends were cut.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for producing wooden straws, and more particularly to a method for producing wooden straws by rolling a veneer into a cylindrical shape. [Background technology]

[0002] Plastic straws are widely used, but because they are harmful to the environment, alternatives are needed. Paper straws are also used as an alternative, but because paper is prone to absorbing moisture, when a paper straw is placed in a drink, it becomes soft over time and loses strength, causing the problem of breaking. To solve this problem, wooden straws made from highly durable wood are known (for example, Patent Document 1).

[0003] Specifically, it is a wooden straw made by molding a sheet of straight-grained wood (veneer) into a straw shape and fixing it with a water-resistant adhesive. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Utility Model Registration No. 3220607 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when processing and molding the veneer, the material used to make wooden straws, into straw shapes, there was an issue of many defective products being produced.

[0006] Therefore, the present invention has been made in consideration of the above problems, and one of the objects of the present invention is to provide a method for producing wooden straws more reliably while reducing the occurrence of defective products. [Means for solving the problem]

[0007] In order to achieve the above object, the present invention has at least the following configuration or executes the following procedure. In the following description, reference numerals and the like shown in the drawings may be added to facilitate understanding of the present invention, but each component of the present invention is not limited to those shown in the drawings, and should be interpreted broadly to the extent that a person skilled in the art can technically understand.

[0008] A manufacturing method for wooden straws according to one aspect of the present invention is a method for manufacturing wooden straws, comprising a first wetting step of wetting a veneer having a thickness of 0.1 mm to 0.4 mm, a coating step of applying an adhesive to the wetted veneer, a winding step of rolling the adhesive-coated veneer into a cylindrical shape, a first drying step of drying the cylindrically-rolled veneer, a second wetting step of wetting the dried cylindrical veneer, a cutting step of cutting both ends of the wetted cylindrical veneer, and a second drying step of drying the cylindrical veneer with both ends cut. This configuration makes it possible to more reliably manufacture wooden straws.

[0009] In addition, preferably, the pH of the liquid used to moisten the veneer in the first moistening step and the second moistening step is in the range of pH6 to pH7. This structure can prevent black stains from appearing on wooden straws, presumably because it inhibits the reaction between lignin or tannin contained in wood and alkali.

[0010] In addition, preferably, the winding step is performed on a paper cloth. This configuration allows the veneer to be wrapped around the core rod more reliably.

[0011] In addition, preferably, in the first drying step, an end portion of the cylindrically wound veneer is secured by a clip. With this configuration, the cylindrical shape can be more reliably maintained during drying.

[0012] Preferably, the clip is made of silicon. With this configuration, even if adhesive is attached to the clip, the clip can be easily removed, since adhesive does not easily adhere to a silicone clip.

[0013] Preferably, the first drying step is characterized in that drying is performed at an atmospheric temperature of 60° C. to 90° C. for at least 3 hours. With this configuration, the veneer can be sterilized more reliably.

[0014] Preferably, the adhesive has a viscosity in the range of 4000 to 4400 cps. This configuration makes it easy to roll the veneer into a cylindrical shape, with almost no tucks occurring. Effect of the Invention

[0015] As described above, according to the present invention, the occurrence of defective products can be reduced and wooden straws can be manufactured more reliably. [Brief description of the drawings]

[0016] [Figure 1] 1 is a wooden straw 10 manufactured by a wooden straw manufacturing method 100 according to the present invention. [Diagram 2] FIG. 1 is a process diagram showing a manufacturing method 100 for wooden straws according to the present invention. [Diagram 3] FIG. 4 is a diagram showing a winding process 400 in which a veneer is wound into a cylindrical shape. [Figure 4] This is a diagram showing the end portion 410 of a cylindrically rolled veneer being fastened with a clip 420. [Diagram 5] 13 is a diagram showing the shape of a clip 420. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Note that the embodiment described below is merely a specific example for carrying out the present invention, and is not intended to limit the present invention.

[0018] Fig. 1 shows a wooden straw 10 manufactured by a wooden straw manufacturing method 100 according to the present invention. It is about 20cm to 25cm long, and is formed by overlapping veneer in a spiral shape. Since it is overlapped in a spiral shape, it has sufficient strength.

[0019] 2 is a process diagram showing a method 100 for manufacturing wooden straws according to the present invention. The method 100 for manufacturing wooden straws according to the present invention includes a first wetting step 200 for wetting the veneer, a coating step 300 for coating the wet veneer with adhesive, a winding step 400 for winding the veneer coated with adhesive into a cylindrical shape, a first drying step 500 for drying the cylindrically wound veneer, a second wetting step 600 for wetting the dried cylindrical veneer, a cutting step 700 for cutting both ends of the wet cylindrical veneer, and a second drying step 800 for drying the cylindrical veneer with both ends cut.

[0020] The wood used for veneer is softwood such as cedar and cypress. This is because softwood such as cedar and cypress have excellent processing characteristics. Wood is mainly harvested, but thinned wood can also be used because this allows for more effective use of resources. Furthermore, broadleaf trees such as cherry, zelkova, and beech can also be used if necessary.

[0021] For the veneer, we use veneer with a straight grain. This is because the force generated when rolling is distributed evenly on straight grain veneer, making it less likely to tear. However, if veneer with a cross grain instead of straight grain is used, there is a problem that it will tear more easily when rolling.

[0022] The size of the veneer is in the range of 40 to 80 mm in length, 200 to 240 mm in width, and 0.1 mm to 0.4 mm in thickness, and preferably 60 mm in length, 220 mm in width, and 0.15 mm in thickness. With a veneer of this size, a wooden straw 10 of an appropriate length can be manufactured. The size of the veneer may be changed depending on the length and thickness of the wooden straw 10.

[0023] In the first wetting step 200, the veneer is wetted for at least 30 minutes in an enclosed space at room temperature with a humidity of 90% to 100%. Note that a humidifier or the like is used to set these conditions.

[0024] By wetting the veneer under these conditions, it is possible to make the veneer contain an appropriate amount of moisture. Specifically, 20% to 80% of the weight of the dry veneer is given to the veneer. By wetting the veneer and allowing it to contain the appropriate amount of moisture, it becomes a veneer with appropriate flexibility. This makes the veneer easier to process. If the veneer is not wetting in the first wetting step 200, the veneer will not be flexible in the next step, the winding step 400, and a problem will arise in that it will tear along the grain.

[0025] The liquid used for wetting is tap water adjusted to a pH range of 6 to 7 using a commercially available water purifier or the like. When the pH is within this range, it is possible to suppress the darkening that occurs on the surface of the wooden straw 10. This is thought to be because a pH that is on the acidic side suppresses the reaction between the lignin or tannin contained in the wood and the alkali, thereby suppressing discoloration. However, if the liquid used for wetting is on the acidic side, specifically below pH 6, a problem occurs in that the veneer is damaged by the acid and becomes more likely to crack.

[0026] In the application step 300, a brush is used to apply adhesive to the veneer that has been moistened in the first wetting step 200. By using a brush, the adhesive can be applied quickly and more reliably. In addition, a mesh screen is used when applying the adhesive with a brush. By using the mesh screen, the adhesive can be applied evenly. The mesh screen is 240 mm wide by 30 mm long. Depending on the situation, the adhesive may be applied by a method other than using a brush and mesh screen.

[0027] A cross-linking emulsion type adhesive is used as the adhesive. By using a cross-linking emulsion type adhesive, it is possible to bond the veneers together and to provide the wooden straw 10 with the ability to prevent water absorption. It is also possible to prevent the wooden straw 10 from re-emulsifying when placed in a beverage such as water or juice, and to prevent the components of the wood from dissolving in the beverage. Note that adhesives other than cross-linking emulsion type adhesives may be used as long as they are highly water-resistant and safe.

[0028] The components and ratios of the cross-linking emulsion type adhesive used in this embodiment are 46% to 48% by weight of polyvinyl acetate, 1% to 3% by weight of polyvinyl alcohol, 46% to 48% by weight of water, 1% to 6% by weight of aluminum chloride, and 1% to 5% by weight of diethylene glycol monobutyl ether. The cross-linking emulsion type adhesive used in this embodiment has the characteristic of not emitting formaldehyde through the cross-linking reaction.

[0029] Furthermore, in the case of the cross-linking emulsion-type adhesive used in this embodiment, cross-linking proceeds even at room temperature, but cross-linking can be accelerated by heating.

[0030] The viscosity of the emulsion-type adhesive used in this embodiment is in the range of 4000 cps to 4400 cps. With a viscosity in the range of 4000 cps to 4400 cps, the veneer can be easily rolled into a cylindrical shape in the next step, the rolling step 400, with almost no tack occurring. However, the viscosity of the adhesive is not limited to this and can be adjusted according to the properties of the veneer, the moisture content, temperature, humidity, rolling method, etc.

[0031] Furthermore, adhesives that have strong tack after application will adhere to the veneer without shifting when it is rolled, resulting in gaps and insufficient adhesion. Diluting the adhesive weakens the tack, making it easier to shift, but the adhesive strength decreases and water resistance deteriorates. Conversely, adhesives with too little tack will leave areas where the veneer does not adhere when rolled, preventing it from becoming one piece.

[0032] The emulsion-type adhesive used in this embodiment is a 50% solids adhesive applied to the veneer at a rate of 50 to 100 g / m 2 Preferably, the coating is applied at a rate of 60 to 80 g / m 2 If the amount of adhesive applied is small, the adhesion between the veneers is insufficient, and the wooden straw 10 is likely to peel off. Conversely, if the amount of adhesive applied is too large, the adhesive will overflow onto the surface of the wooden straw 10.

[0033] The area to which the emulsion-type adhesive is applied is about 1 / 2 to 1 / 3 of one side of the veneer. Specifically, it is about 30 mm wide across the entire width of the veneer, that is, about 200 to 240 mm wide by 30 mm long. If the emulsion-type adhesive is applied to this area, it becomes easier to roll the veneer into a cylindrical shape in the next step, the rolling step 400, and tacks are less likely to occur.

[0034] FIG. 3 shows the winding process 400 in which the veneer is rolled into a cylindrical shape, with FIG. 3(a) showing the start of the winding, FIG. 3(b) showing the middle of the winding, and FIG. 3(c) showing the end of the winding. In the winding process 400, the veneer coated with adhesive in the coating process 300 is rolled into a cylindrical shape. Specifically, the veneer coated with adhesive in the coating process 300 is wound spirally around a core rod made of stainless steel (diameter 4 mm, length about 30 cm). When the winding starts, the veneer is wound so that the core rod and the veneer are at an angle of 4° to 20°. By winding at an angle of 4° to 20°, it is possible to prevent the veneer from cracking. The particularly preferable range is 4° to 10°. However, if the veneer is wound at an angle of less than 4°, that is, in a state close to parallel, a problem occurs in that the veneer will tear along the grain of the wood. Furthermore, if the angle is large, i.e., 20° or more, the veneer will tend to return to its original shape, which can cause problems such as tearing. When starting to roll, the veneer is rolled from a place where no adhesive is applied, and as the veneer is being rolled, the surface where the adhesive is applied overlaps and adheres to the veneer. The end of the roll 410 is then firmly adhered to form a cylindrical veneer.

[0035] When wrapping the veneer around the core rod, the core rod is pulled towards you while wrapping. This allows the veneer to be wrapped around the core rod in a cylindrical shape without leaving any gaps. Also, the veneer is wrapped within five minutes of applying the adhesive. This is because if the veneer is not wrapped within five minutes, some of the adhesive will harden, increasing the possibility of poor adhesion.

[0036] Additionally, the winding process 400 is performed on a paper cloth. By working on a paper cloth, the veneer can be more reliably wound around the core rod. This is because the moisture in the moistened veneer is evenly distributed over the entire veneer, and the paper cloth deforms in response to the pressure applied from above, making it less likely that gaps will form between the core rod and the veneer.

[0037] FIG. 4 shows the end 410 of the veneer rolled into a cylinder being secured with a clip 420. After the veneer is rolled into a cylinder, the core rod is removed, and then the end 410 of the veneer is secured with a silicon clip 420. It is recommended to dry the veneer with the clip 420 attached until sufficient adhesion is achieved. This allows the veneer to maintain its cylindrical shape even after drying in the next step, the first drying step 500. Note that the silicon clip 420 is easy to remove even if adhesive is attached, so that even if the veneer is clamped with adhesive attached, it can be easily removed. Note that the clip 420 is not limited to silicon, and an inexpensive rubber clip may be used.

[0038] Fig. 5 is a diagram showing the shape of clip 420. Fig. 5(a) is a plan view of clip 420, and Fig. 5(b) is a perspective view of clip 420. Clip 420 has a cylindrical shape with an outer diameter of 10 mm, an inner diameter of 4 mm, and a length of about 12 mm, with part of the cylinder cut out into a sector shape. This shape makes it easy to attach to and remove from a cylindrical veneer.

[0039] In the first drying step 500, the veneer rolled into a cylindrical shape in the rolling step 400 is dried. In the drying step, the veneer is dried for about 3 to 4 hours at an atmospheric temperature of about 60°C to 90°C while exchanging outside air. Drying for about 3 hours at this temperature allows the moisture in the adhesive to be sufficiently dried and cross-linked. The veneer can also be sterilized. A dehumidifying dryer may be used in the first drying step 500. Once the veneer is sufficiently dried, the clips 420 are removed.

[0040] In the second wetting step 600, the tubular veneer dried in the first drying step 500 is moistened. By wetting, when both ends of the tubular veneer are cut in the next cutting step 700, cracks and burrs on the cut surface can be prevented. This is because when both ends of the tubular veneer are cut, the veneer is hard and the fibers become loose and burrs occur. In order to prevent this burrs, the tubular veneer dried in the first drying step 500 is moistened and then cut. In addition, by wetting the veneer in the second wetting step 600, the formaldehyde contained in the veneer can be removed. Generally, wood is stressed when processed, which generates formaldehyde, but we use the fact that formaldehyde can be removed by wetting.

[0041] The liquid used for wetting is tap water whose pH has been adjusted using a commercially available water purifier or the like. The pH is set in the range of pH6 to pH7. When the pH is within this range, it is possible to suppress the darkening that occurs on the surface of the wooden straw 10. This is thought to be because when the pH is on the acidic side, it suppresses the reaction between the lignin or tannin contained in the wood and the alkali, thereby suppressing discoloration. However, if the liquid used for wetting is on the acidic side, specifically, if the pH is below 6, a problem occurs in that the veneer is damaged by the acid and becomes more likely to crack.

[0042] In the cutting process 700, both ends of the tubular veneer moistened in the second moistening process 600 are cut. The length to be cut can be adjusted to the desired length of the straw. As a guide, the cut length is about 2cm to 5cm from the end of the tubular veneer. After cutting, the veneer is immersed again in water at about 40°C to 60°C and pH 6 to 7, and then moved to the next process.

[0043] In the second drying step 800, the cylindrical veneer, both ends of which have been cut in the cutting step 700, is dried. The drying temperature is an atmospheric temperature of about 80°C to 90°C, and the veneer is dried for about three hours. Drying at this temperature for about three hours also makes it possible to sterilize the veneer. Note that a dehumidifying dryer may be used in the second drying step 800.

[0044] Through the above steps, the veneer becomes the wooden straw 10. Note that although the wooden straw manufacturing method 100 according to the present invention is premised on manual manufacturing, it may also be done by machine.

[0045] Although adhesive is used in the wooden straw 10 produced by the wooden straw manufacturing method 100 of the present invention, the main material of the wooden straw 10 is veneer, so it can be disposed of as combustible waste.

[0046] As described above, according to the wooden straw manufacturing method 100 of the present invention, the wooden straw 10 can be manufactured more reliably. [Industrial Applicability]

[0047] By using the wooden straw manufacturing method 100 of the present invention, the occurrence of defective products can be more reliably reduced, which leads to cost reduction. [Explanation of symbols]

[0048] 10 Wooden Straws 100 How to make wooden straws 200 First wetting step 300 Coating process 400 Winding process 410 End of winding 420 clips 500 1st drying process 600 Second Wetting Process 700 Cutting process 800 2nd drying process

Claims

1. A method for producing wooden straws, comprising the steps of: A first wetting step of wetting a veneer having a thickness of 0.1 mm to 0.4 mm; a coating step of applying an adhesive to the wet veneer; a winding step of winding the adhesive-coated veneer into a cylindrical shape; A first drying step of drying the cylindrically wound veneer; A second wetting step of wetting the dried cylindrical veneer; A cutting step of cutting both ends of the wet tubular veneer; A second drying step of drying the cylindrical veneer having both ends cut, The method for manufacturing wooden straws, wherein the pH of the liquid used to wet the veneer in the first wetting step and the second wetting step is acidic, ranging from pH 6 to less than pH 7.

2. The method for manufacturing wooden straws according to claim 1, wherein the winding step is carried out on a paper cloth.

3. 3. The method for manufacturing wooden straws according to claim 1 or 2, wherein in the first drying step, the end of the rolled veneer is secured in place with a clip.

4. The method for manufacturing wooden straws according to claim 3, wherein the clip is made of silicone.

5. The method for manufacturing wooden straws according to claim 4, characterized in that the shape of the clip is such that, when the clip is attached to the end of the cylindrically wound veneer, the cross-sectional shape when cut perpendicular to the longitudinal direction of the cylindrically wound veneer is approximately C-shaped.

6. The method for manufacturing wooden straws according to any one of claims 1 to 5, wherein in the first drying step, the straws are dried at an atmospheric temperature of 60°C to 90°C for at least 3 hours.

7. The method for manufacturing wooden straws according to any one of claims 1 to 6, characterized in that the viscosity of the adhesive is in the range of 4000 cps to 4400 cps.

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