TWI251537B - Sheet for leaching - Google Patents

Abstract

A sheet (1) for leaching in accordance with the present invention comprises a laminated sheet comprised of a long fiber non-woven fabric (2) comprising a synthetic fiber of a high melting point resin having a METSUKE of 5 to 30 g/m<2> and a short fiber non-woven fabric (3) comprising a synthetic fiber of a low melting point resin and having a METSUKE of 3 to 15 g/m<2>. The short fiber non-woven fabric (3) comprises fibers having a fiber length of 3 to 15 mm randomly dispersed, deposited, and thermally adhered to one another in a dry manner. In a chart of a void diameter distribution of the sheet for leaching, the maximum peak exhibits a distribution percentage ten times or more that of another peak.

Description

1251537 (1) 发明, the description of the invention (the description of the invention should be described: the technical field, the prior art, the content, the embodiment and the schematic description of the invention) TECHNICAL FIELD The present invention relates to leaching raw materials such as black tea, coffee, green tea, and traditional Chinese medicine. The leaching sheet used was taken out. The leaching sheet used for the extraction of the leaching raw materials such as black tea, coffee, green tea, and traditional Chinese medicines requires good leaching property, and the leaching sheet used in the form of a tea bag must have bag-making properties. That is, the use of a heat sealer requires easy bag making. Then, in the prior art, the leaching sheet is made of a synthetic fiber nonwoven fabric having low water absorbing property and high leaching property. In addition, it is suitable for the leaching sheet for bag making (FULL VEIL), a spunbonded nonwoven fabric made of laminated high-melting polyester fibers, and a low-melting polyester fiber. The combed hair is not woven. The sheet for leaching of the high-melting point spunbonded nonwoven fabric and the low-melting combed nonwoven fabric is arranged such that the low-melting comb is not woven on the inner side, the two leaching sheets are overlapped, and a heat sealing machine is used. The heating head of the heat sealing machine does not melt the attached fibers, and can be easily heat-sealed. However, the woven sheets of the prior spunbonded nonwoven fabric and the combed nonwoven fabric are laminated, and the fibers of the comb-non-woven fabric are assigned 1251537 in a specific direction set by the carding machine ( 2) The direction cannot be uniformly dispersed in the irregular direction, so the pore diameter distribution of the non-woven voids will be widely distributed. Therefore, when the viscosity of the sheet for leaching is adjusted to obtain a desired liquid passing speed, the fine powder of the leaching raw material is passed through the sheet for leaching, and further, the fine powder of the leaching material is completely prevented from passing through There is a problem that the flow rate is extremely low. In addition, in the recent market where the width of the sealing portion of the tea bag is reduced from the previous 5 mm to about 2 mm, when the sealing width is reduced by laminating the previously woven non-woven fabric and the woven fabric sheet. Since the comb-non-woven fabrics having the sealing function are aligned in a specific direction and cannot be uniformly dispersed in the irregular direction, there is a problem in that the sealing portion has a portion having a low sealing strength. In order to solve such a problem, the present invention relates to a sheet for leaching which has a bag-like property, and which does not cause a portion having a low sealing strength in the sealing portion even when the width of the sealing is reduced, and the object is a leaching material. At the time of extraction, one of the ramen faces maintains an ideal liquid passing speed, and on the other hand, the fine powder of the leaching raw material is prevented from passing. DISCLOSURE OF THE INVENTION The present inventors have found that when a high-melting point non-woven fabric and a low-melting-point non-woven fabric are laminated, a low-melting point non-woven fabric is formed by dry-discretely dispersing and stacking short fibers and mutually thermally bonding these parent points. Because any part of the short fiber in the irregular direction can be dispersed with the same intensity sentence, even if the non-woven fabric 1251537 Ο) 丨 money ^! ^ for heat sealing, in addition, the pore size distribution of the non-woven fabric is concentrated in extremely narrow Since the range is small, there is no void having an excessively large pore diameter, and when the leaching raw material is taken out, the fine powder of the leaching raw material can be prevented from passing. That is, the present invention provides a sheet for leaching, characterized in that a sheet for leaching is formed by laminating at least a part of a synthetic fiber of a high-melting point resin to form a long-fiber non-woven fabric having a viscosity of 5 to 30 g/m2. And at least a part of the synthetic fiber of the low melting point resin, forming a short fiber non-woven fabric with a viscosity of 3 to 15 g/m2, and a short fiber non-woven fabric, which is a dry-type irregularly dispersed fiber with a fiber length of 3 to 15 mm, which is mutually heat-adhesive. In the pore size distribution map shown by the relationship between the pore diameter of the void of the sheet for leaching and the distribution ratio thereof, the distribution ratio of the maximum peak is 10 times or more of the other peak distribution ratio. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing a sheet for leaching of the present invention. Fig. 2 is a photograph showing the alignment state of the fibers of the empty bag non-woven fabric (a) and the carded nonwoven fabric (b). Fig. 3 is an explanatory view of a sealing strength test method. Fig. 4 is a view showing the pore size distribution of the voids of the sheet for leaching of the first embodiment. Fig. 5 is a view showing the pore size distribution of the voids of the sheet for leaching of Comparative Example 1. -9- 1251537 (4) 丨健_苏 Figure 6 is a pore size distribution diagram of the voids of the leaching sheet of Comparative Example 2. Fig. 7 is a view showing the pore size distribution of the voids of the sheet for leaching of the second embodiment. Fig. 8 is a view showing the pore size distribution of the voids of the sheet for leaching of the second embodiment. Fig. 9 is a view showing the pore size distribution of the voids of the sheet for leaching of the second embodiment. Fig. 10 is a view showing the pore size distribution of the voids of the sheet for leaching of the second embodiment. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the drawings. Fig. 1 shows a sheet 1 for leaching of the present invention, which has a laminated structure of a long-fiber nonwoven fabric 2 and a short-fiber nonwoven fabric 3. Among them, a long-fiber non-woven fabric, at least a part of which is a synthetic fiber of a high-melting point resin, is preferably formed of at least a part of a synthetic fiber of a high melting point resin having a melting point of 170 ° C or more. Thereby, the short fibers are not woven on the inner side, and the two sheets for leaching are superposed, and in the case of using a heat sealer, the heat head of the heat sealer prevents the fibers from being melted and adhered. Here, at least a part of the synthetic fiber having a high melting point resin having a melting point of 170 ° C or more forms a long fiber non-woven fabric, and a synthetic fiber of a long fiber non-woven fabric is formed, which comprises a synthetic resin having a melting point of only 170 ° C or more. In the case of a synthetic resin composed of a synthetic resin having a melting point of 170 ° C or more and a synthetic resin having a melting point of less than 170 ° C; at least the surface layer (sheath) is composed of a synthetic resin having a melting point of 170 ° C or more. The situation of the fiber of the sheath structure -10-

1251537 (5) Synthetic resin with a melting point of 170 ° C or higher, which can be exemplified by high melting point polyester (high melting point polyethylene terephthalate: melting point 245 ° C), polyamide (nylon) 66: melting point 245 ° C), polyphenylene sulfide (melting point 290 ° C), polylactic acid (melting point 178 〇 C) and the like. The fiber diameter of the synthetic fiber forming the long-fiber non-woven fabric is preferably 3 μηι or less from the viewpoint of the stability of the nonwoven fabric.

In the method of non-woven synthetic fibers, melt-blown or the like may be used, but the lattice is not blocked, and from the viewpoint of obtaining high strength, it is preferable to be spun. In addition, the long fiber non-woven fabric has a viscosity of 5 to 30 g / m 2 . When the viscosity is less than 5 g/m2, the strength is insufficient. On the other hand, when the viscosity exceeds 30 g/m2, the leaching property or mechanical applicability is low, which is not preferable.

Further, in the leaching sheet of the present invention, the short fiber non-woven fabric, at least a part of which is a synthetic fiber of a low melting point resin, is preferably a synthetic fiber of a low melting point resin having at least a melting point of 80 ° C or more and less than 170 ° C. Formed. Thereby, the short fibers are not woven on the inner side, and the two sheets for leaching are superposed, and the heat sealing machine can be used to easily seal the heat. Here, at least a part of the synthetic fiber having a low melting point resin having a melting point of 80° C. or more and less than 170° C. constitutes a short fiber non-woven fabric, and a synthetic fiber of a short fiber non-woven fabric is formed, which comprises only a melting point of 80° C. or more. a case where a synthetic resin having a temperature of 170 ° C is formed; and a synthetic resin having a melting point of 80 ° C or more and less than 170 ° C constitutes a mixed fiber of fibers and fibers other than the melting point; to -11 -

1251537 (6)

The case where the surface layer is composed of a synthetic resin having a melting point of 8 or less (TC above 170 ° C) constitutes a core-sheath structure. Even in the case where the long-fiber non-woven fabric is bonded to the short-fiber non-woven fabric, it is preferable that the non-woven fabric void is not damaged. The fiber of the core-sheath structure is used. Further, from the viewpoint of improving the bonding strength between the long-fiber non-woven fabric and the short-fiber non-woven fabric, the fibers forming the long-fiber non-woven fabric and the fibers forming the short-fiber non-woven fabric are preferably made of the same kind of resin, in particular, In the case of a core-sheathed fiber, it is preferable to use a resin of the same type as the resin of the surface layer (sheath). A synthetic resin having a melting point of 80 ° C or more and less than 170 ° C may be exemplified by a low melting point polyester (low melting) Point polyethylene terephthalate: melting point 100~160 ° C), polyethylene (melting point 90 ~ 140 ° C), polypropylene (melting point 160 ~ 168 ° C) and so on.

Further, the fiber of the core-sheath structure may be, for example, a core/sheath, and is a high melting point polyester/low melting point polyester, a high melting point polyester/polyethylene, a polypropylene/polyethylene, or the like. The synthetic fiber forming the short fiber non-woven fabric has a fiber length of 3 to 15 mm, preferably 5 to 7 mm. When the fiber length is too short, the strength of the non-woven fabric is lowered, and in addition, as the fiber density becomes large, the liquid passing speed becomes slow. Conversely, when the fiber length is too long, it will make it difficult to uniformly disperse the fibers. The fiber diameter of the synthetic fiber forming the short fiber non-woven fabric, and the leaching material is also related to the pore size distribution of the sheet for leaching to be applied. For example, the sheet for leaching is used in a general black tea bag, preferably 0.1. ~3.0d( -12- 1251537 l_ (7) : Daniel), Ο . 5~2 . Od is better. When the fiber diameter is too small, the pore diameter of the non-woven fabric becomes small, and the liquid passing speed becomes slow. On the other hand, when the fiber diameter is too large, the fine powder of the leaching raw material such as tea leaves is passed through the nonwoven fabric, and the texture or appearance of the extract liquid is deteriorated. In the method of non-woven synthetic fibers, first, the fibers are dispersed by irregularly dispersing the fibers, and secondly, the intersections of the fibers are thermally bonded to each other. More specifically, the web is formed by an empty bag method, and the web is heat-treated with an embossing wheel, calendering or the like. In the web formed by the empty bag method, the fibers will be dispersed in a uniform thickness in an irregular direction. Further, even if the web is heat-treated by an embossing wheel or the like, the uniformity of fiber dispersion is not impaired. Therefore, in the short fiber non-woven fabric thus formed, the pore size distribution is concentrated in a narrow range, and if the pore size distribution map is obtained by the relationship between the pore diameter and the distribution ratio (°/〇), the distribution ratio of the maximum peak value is other peak distribution ratio. More than 10 times, preferably, the pore size distribution is not less than 1 〇〇μηι, more preferably 50 μηι or less, and has a single ♦ value. Further, in the present invention, the pore size distribution is measured by the bubble point method (JIS Κ 3832). Further, the pore size distribution of the short fiber non-woven fabric thus formed can be sharply controlled by adjusting the fiber diameter and the viscosity. In addition, the non-woven fabric in which the fibers are dispersed in an irregular direction can be obtained by the wet paper method, but from the viewpoint of productivity, it is preferable to use the empty bag method 1251537 (8)

In the present invention, the method of laminating the long-fiber non-woven fabric and the short-fiber non-woven fabric may be formed by separately forming the long-fiber non-woven fabric and the short-fiber non-woven fabric, and then laminating them by heat treatment such as embossing, rolling, or the like. Further, the web of the short fiber non-woven fabric may be formed on the long-fiber non-woven fabric, and heat-treated by embossing, rolling, or the like, and the web non-woven fabric forming the short-fiber non-woven fabric, and the short-fiber non-woven fabric and the long-fiber non-woven fabric may be simultaneously formed. Lamination bonding.

According to the leaching sheet of the present invention, a short fiber non-woven fabric having a low melting point and a long fiber non-woven fabric having a high melting point are laminated, and a pore size distribution of the short fiber non-woven fabric is concentrated in a narrow range as described above, and on the other hand, a long fiber non-woven fabric is used. When the pore diameter is large, as the pore size distribution of the entire sheet for leaching, for example, the pore size distribution map of the relationship between the pore diameter and the distribution ratio (%) is obtained, the distribution ratio of the maximum peak value is also 10 times or more of the other peak distribution ratio, preferably. Therefore, the pore size distribution has a single symplectic value with a non-uniform width of ΙΟΟμιη or less, preferably 50 μm or less. Thus, the desired liquid passing rate is ensured, and when the leaching raw material is taken out, the fine powder of the leaching raw material can be prevented from passing through the leaching sheet. Further, when the sheet for heat-sealing the sheet is heat-sealed, the low-melting point fiber which is a non-woven fabric of the non-woven fabric is dispersed in a uniform thickness in an irregular direction, so that heat can be applied to the same strength even in any part of the non-woven fabric. seal. Therefore, even if the sealing width is narrow, in the sealing portion, a portion having insufficient sealing strength will not be produced. As described above, the sheet for leaching of the present invention is an extremely useful sheet for forming a tea bag which is a leaching material such as black tea, coffee, green tea or Chinese medicine, which is described in the paragraph -14-1251537. As shown in Fig. 1, the leaching sheet of the present invention has a laminated structure of long-fiber nonwoven fabric 2 and short-fiber nonwoven fabric 3, and may be laminated with other woven fabrics, non-woven fabrics or the like as necessary. For example, in order to improve the bonding strength between the long-fiber non-woven fabric and the short-fiber non-woven fabric, a non-woven fabric for bonding may be provided between them. Hereinafter, the present invention will be specifically described based on examples. Test Example One core/sheath using high melting point polyethylene terephthalate / low melting point polyethylene terephthalate core sheath construction fiber (fiber diameter 1.0 d, fiber length 5 mm), with empty bag method The web was formed into a web, and an air bag was used to make an empty bag non-woven fabric. In addition, the same fiber was used to make a comb non-woven fabric. Next, a sample of 9.0 cm x 6.0 cm and ten samples of 100 cm x 100 cm were cut out from each non-woven fabric, and the weight was measured. The results are shown in Tables 1 and 2. In addition, Figure 2(a) shows a photograph of an empty bag non-woven fabric, and Figure (b) shows a photo of a comb non-woven fabric -15- 1251537

Do) I invention description Continued page I Table 1

[g / 9.0 cmx6. Ο cm] Sample empty bag non-woven combed wool non-woven fabric 1 0.044 0.056 2 0.045 0.054 3 0.044 0.059 4 0.043 0.057 5 0.044 0.055 6 0.044 0.056 7 0.045 0.059 8 0.044 0.057 9 0.044 0.055 10 0.044 0.058 Average 0.044 0.057 standard deviation 0.00054 0.00162

-16- 1251537 发_明绩买(11) Table 2 [g/ lOOcmxlOO cm] Sample empty bag non-woven carded wool non-woven fabric 1 8.14 10.42 2 8.02 10.58 3 8.29 10.32 4 8.23 10. 12 5 8.15 10.71 6 8.31 10.44 7 8.22 10.28 8 8.16 10.41 9 8.07 10.35 10 7.99 10.40 Average 8.16 10.40 Standard deviation 0.10245 0.15238 According to Table 1, Table 2, by comparing the standard deviation of the weight of the empty bag non-woven fabric and the comb non-woven fabric, it can be known that the empty bag non-woven fabric is more woven than the non-woven fabric. There is very little unevenness in the grid. Further, from Fig. 2, it can be seen that the empty bag non-woven fabric fibers are uniformly dispersed in an irregular direction, and the comb-non-woven fabric fibers are aligned in a certain direction, and the adhesiveness is uneven. In the first embodiment, the first comparative example and the second comparative example, the high-melting polyester with a fiber diameter of 2 · Od is used to make a spunbonded non-woven fabric, and the above-mentioned 17-(12) 1251537 invention illustrates that the use of the heart/sheath is a high melting point.埽对#

Desirable, 芯 dimethyl dimethyl terephthalate core sheath structure fiber diameter mm), the empty bag method to form the beam belly, and w 蜃 flower, dot grid 12g / m2) on the laminated empty bag A small woven fabric (adhesive sheet (Example 1). In addition, the use of an empty bag non-woven fabric, m, _ degree is SI mm), in the same as the above-mentioned spunbond 1 'cloth (viscous laminated comb non-woven fabric ( The 淳 / / / / / / / / / / / / / / / / In addition to g/m2, the laminated empty bag non-woven fabric is produced on the spunbonded nonwoven fabric. (1) Sealing strength test The empty bag is not woven on the inner side, and the heat sealing port (heating temperature 150 ° C) is 15 mm wide. , a cut shape (15 mm x 50 mm), and a peeling load of the shape 4 which is torn by the non-sealing side. In Fig. 3, the symbol 2 indicates that the number 3' indicates an empty bag non-woven fabric. Material, also set #毛尧ester / low melting point polyethylene 2 · Od, fiber length 5 in spunbonded non-woven fabric (6g / m2) leaching with ^ Wei (but, The material of the length of 12g/m2) (Comparative Example 1). In the same manner as in the first comparative example 1, the sheet for E was used. The two sheets for leaching were as shown in the short form of Fig. 3, and the sealing portion was calculated. Sticky non-woven fabric, non-woven fabric on the inside, -18-

1251537 (13) and perform overlapping and heat sealing, and calculate the peeling load of the sealing portion. The results are shown in Table 3. Table 3 [kg/15 mm] sample Example 1 Comparative Example 1 0.22 0.46 2 0.22 0.68 3 0.23 0.37 4 0.21 0.39 5 0.21 0.41 6 0.22 0.70 7 0.24 0.62 8 0.23 0.33 9 0.20 0.41 10 0.23 0.54

Average 0.22 0.49 standard deviation 0.01136 0.12778

From Table 3, as compared with the sheet for leaching of Comparative Example 1, it was found that the sheet for leaching of Example 1 had extremely small unevenness in sealing strength. (2) Pore size distribution Each of the leaching sheets of Example 1, Example 2, Comparative Example 1, and Comparative Example 2 was measured by a bubble point method (JIS K3832) using a pore size distribution machine (Perm Poro Meter) manufactured by PMI Corporation, USA. The pore size distribution of the voids. Showing results in -19- 1251537

Figure 4 ~ Figure 10. Further, regarding the leaching sheet of the second embodiment, four places (Fig. 7 to Fig. 10) in which the positions in the width direction are different from each other were measured. From the above figures, the leaching sheet of Comparative Example 1 and Comparative Example 2 has a pore size distribution having a non-uniformity of 140 μm or more and having a plurality of peaks therein, and the pore size distribution of the leaching sheet of Example 1 is less than or equal to ΙΟμηι. There is a single peak in the heterogeneity, and it can be known that the pore size distribution is concentrated there. Further, at the measurement point of the sheet for leaching of Example 2, the maximum peak distribution ratio was also 10 times or more of the other peak distribution ratio, and it was found that the pore size distribution was concentrated on the maximum value. Industrial Applicability As described above, according to the sheet for leaching of the present invention, even when the width of the seal is reduced, the unevenness of the seal strength of the seal portion can be remarkably reduced. In addition, since the pore size distribution of the non-woven fabric gap can be sharply controlled, it is preferable to make the pore size distribution of the non-woven fabric voids have a single peak value, so that when the leaching raw material is extracted, on the one hand, the ideal liquid passing speed can be maintained, and on the other hand, the leaching can be prevented. The passage of the fine powder of the raw material. -20-

Claims (1)

1251537 Picking up, patent application scope 1. A sheet for leaching, characterized by laminating long fiber non-woven fabric, at least a part of which is composed of synthetic fibers of high melting point resin, and having a viscosity of 5 to 30 g/m2; a fiber non-woven fabric, at least a part of which is composed of a synthetic fiber of a low melting point resin, and has a viscosity of 3 to 15 g / m 2 , wherein the short fiber is not woven, and the fiber having a length of 3 to 15 mm is dispersed in a dry irregular manner. In the pore size distribution diagram shown by the relationship between the pore diameter of the void of the leaching sheet and the distribution ratio thereof, the distribution ratio of the maximum peak is 10 times or more of the other peak distribution ratio. 2. The leaching sheet according to item 1 of the patent application has a non-uniform pore size distribution of ΙΟΟμπι or less and a single peak. 3. The leaching sheet according to item 1 of the patent application, wherein the melting point of the high melting point resin is 170 ° C or more, and the melting point of the low melting point resin is 80 ° C or more and 170 ° C or less. 4. The leaching sheet according to claim 1, wherein the fiber constituting the short fiber nonwoven fabric is formed of a low melting point polyester having a core structure formed by a melamine point.