LEE, Chang Seop (9-204, Greenville Jugong Apt. 14-danjiChoji-dong, Danwon-gu, Ansan-si, Gyeonggi-do 425-876, KR)
JUNG, Hyun Joo (5f 502, 881-3 Bongcheon 4-dong, Gwanak-gu, Seoul 151-054, KR)
LIM, Hyun Chang (101 116-15, Sillim 2-dong Gwanak-gu, Seoul 151-855, KR)
PARK, Ji Young (203 Tehearanart, 828-13 Yeoksam-dong Gangnam-gu, Seoul 135-080, KR)
CHUNG, Chan Il (6-907, Hongsil Apt.Samseong 1-dong, Gangnam-gu, ilSeoul 135-866, KR)
CHANG, Jun Keun (501 Granciel Villa, Bangbae 4-dong Seocho-gu, Seoul 137-064, KR)
PARK, Jun Ha (8 Daewolmaeul, Jeongja 3-dong Jangan-gu, Suwon-si, samGyeonggi-do 440-729, 17-1905, KR)
LEE, Chang Seop (9-204, Greenville Jugong Apt. 14-danjiChoji-dong, Danwon-gu, Ansan-si, Gyeonggi-do 425-876, KR)
JUNG, Hyun Joo (5f 502, 881-3 Bongcheon 4-dong, Gwanak-gu, Seoul 151-054, KR)
LIM, Hyun Chang (101 116-15, Sillim 2-dong Gwanak-gu, Seoul 151-855, KR)
PARK, Ji Young (203 Tehearanart, 828-13 Yeoksam-dong Gangnam-gu, Seoul 135-080, KR)
CHUNG, Chan Il (6-907, Hongsil Apt.Samseong 1-dong, Gangnam-gu, ilSeoul 135-866, KR)
CHANG, Jun Keun (501 Granciel Villa, Bangbae 4-dong Seocho-gu, Seoul 137-064, KR)
| Claims
[1] A chip for analyzing fluids comprising: a body; a fluid loading hole formed in one end of the body; a passage switching portion formed in the other end of the body; and a passage formed inside the body to communicate with the fluid loading hole, wherein the passage includes a first channel extending from the fluid loading hole to the passage switching portion to have a first depth, and second channels being open against the first channel and parallel with the first channel to have a second depth, wherein the second depth is greater than the first depth from an end of the fluid loading hole to the one position below the fluid loading hole, and is reduced from one position below the fluid loading hole to the passage switching portion to have the same height as that of the first depth in the passage switching portion. [2] The chip for analyzing fluids according to claim 1, wherein the second channels are formed in both sides of the first channel. [3] The chip for analyzing fluids according to claim 1 or 2, wherein the opposite sides of the second channels to the first channel are opened. [4] The chip for analyzing fluids according to claim 3, wherein the opposite sides of the second channels to the first channel are opened against the one position below the fluid loading hole to the passage switching portion. [5] The chip for analyzing fluids according to claim 1 or 2, wherein the second depth is constant from the fluid loading hole to the one position below the fluid loading hole. [6] The chip for analyzing fluids according to claim 1 or 2, wherein the second depth is continuously reduced from the one position below the fluid loading hole to the passage switching portion. [7] The chip for analyzing fluids according to claim 6, wherein the second depth is linearly reduced from the one position below the fluid loading hole to the passage switching portion. [8] The chip for analyzing fluids according to claim 1 or 2, wherein the second depth is discontinuously reduced from the one position below the fluid loading hole to the passage switching portion. [9] The chip for analyzing fluids according to claim 1 or 2, wherein the one position below the fluid loading hole is in a downstream of a reaction part of the fluid sample and a probe. [10] The chip for analyzing fluids according to claim 1 or 2, further comprising a side wall formed through a part of a passage from the fluid loading hole to the passage switching portion for blocking the first channel against the second channels.
[11] A chip for analyzing fluids comprising: a body; a fluid loading hole formed in one end of the body; a passage switching portion formed in the other end of the body; and a passage formed inside the body to communicate with the fluid loading hole, wherein the passage includes a first channel extending from the fluid loading hole to the passage switching portion to have a first depth, second channels being open against the first channel parallel with the first channel to have a second depth, and third channels being open against the second channels parallel with the second channels to have a third depth, wherein the second depth is greater than the first depth from an end of the fluid loading hole to the one position below the fluid loading hole, and is reduced from one position below the fluid loading hole to the passage switching portion to have the same height as that of the first depth in the passage switching portion, and the third depth is less than or equal to a depth in the one position below the fluid loading hole.
[12] The chip for analyzing fluids according to claim 11, wherein the second channels are formed in both sides of the first channel.
[13] The chip for analyzing fluids according to claim 11 or 12, wherein the second depth is constant from the fluid loading hole to the one position below the fluid loading hole.
[14] The chip for analyzing fluids according to claim 11 or 12, wherein the second depth is continuously reduced from the one position below the fluid loading hole to the passage switching portion.
[15] The chip for analyzing fluids according to claim 14, wherein the second depth is linearly reduced from the one position below the fluid loading hole to the passage switching portion.
[16] The chip for analyzing fluids according to claim 11 or 12, wherein the second depth is discontinuously reduced from the one position below the fluid loading hole to the passage switching portion.
[17] The chip for analyzing fluids according to claim 11 or 12, wherein the one position below the fluid loading hole is in a downstream of a reaction part of the fluid sample and a probe.
[18] The chip for analyzing fluids according to claim 11 or 12, further comprising a side wall formed through a part of a passage from the fluid loading hole to the passage switching portion for blocking the first channel against the second channels. |
Description
CHIP FOR ANALYZING FLUIDS
Technical Field
[1] The present invention relates to a chip with a micro channel through which fluids flow, more particularly, to a chip for analyzing fluids capable of securing a flow rate required for washing using a sample loading hole and at least two channels communicating with each other.
[2]
Background Art
[3] A biologic, chemical, and/or optical analysis of a fluid sample has been widely used for a clinical analysis of blood or body fluids extracted from a patient and a disease diagnosis thereof as well as in the chemical or biotechnological field. In order to provide more miniaturized analysis and/or diagnosis equipment capable of efficiently analyzing a fluid sample, various types of chip structures have been developed and used.
[4] The development of a lab-on-a-chip enables manufacturing of a rapid kit that performs various functions to increase efficiency of analysis and disease diagnosis in one chip. The lab-on-a-chip implements various experimental procedures normally performed in a laboratory on a small-sized chip. In this case, the various experimental procedures involve separation, purification, mixing, labeling, analysis, and washing of samples. Micro-fluidics and micro-LHS related technologies have been widely used to design the lab-on-a-chip. Further, for manufacturing a chip structure implementing the micro-fluidics and micro-LHS, a chip in which a micro channel is implemented using semiconductor circuit design technology has come into the market.
[5] Generally, the following is a description of a procedure of analyzing a small amount of an analysis target material included in a fluid sample such as blood or body fluids using the lab-on-a-chip along a moving passage of the fluid sample with reference to FIG. 1 to FIG. 3 showing a conventional chip 10 for analyzing fluids.
[6] First, a fluid sample (not shown) is loaded through a fluid loading hole 21 formed on one end of an upper plate 11 of the chip 10 for analyzing fluids. The loaded fluid sample flows to the other end of the chip 10 in a channel 22 formed in the chip 10 by surface tension between the fluid sample and inner walls 22a, 22b, 22c, and 22d of the channel 22. The fluid sample flowing through the channel 22 passes through a conjugation part 30 and a reaction part 40. The conjugation part 30 has a label conjugated with the analysis target material included in the fluid sample. The reaction part 40 has a probe for fixing the analysis target material adhered to the inner walls
22a, 22b, 22c, and 22d of the channel 22. The analysis target material included in the fluid sample passes through the reaction part 40 to fix the position thereof with respect to the inner walls 22a, 22b, 22c, and 22d of the channel 22 by the probe.
[7] Since the label of the conjugation part 30 has a fluorescent material, checking light is irradiated to the reaction part 40 to check a resulting intensity of the light. Accordingly, the analysis target material included in the fluid sample may be indirectly inspected. However, there may be a plurality of labels such as labels not conjugated with the analysis target material or floating labels conjugated with the analysis target material not to be fixed thereto by the probe in the reaction part 40. In order to achieve an exact checking, there is a need to remove the floating labels from the reaction part 40. This may be achieved by increasing a flow speed of the fluid sample to a value greater than a predetermined value to perform a washing procedure washing out the floating labels present in the reaction part 40.
[8] Meanwhile, as the loaded fluid sample flows inside the channel 10, due to a weight increase of the fluid sample present in the channel 10 and increase of Poiseuille pressure, a moving speed of the fluid sample is gradually reduced so as not to secure a sufficient flow rate for a time period required for washing.
[9] Methods for solving the above-described problem in the prior art have been attempted. A first method is to secure a necessary flow rate by pumping fluid using an outer pump (not shown) to be flown by force. In a second method, plural capillary channels are further formed in the downstream of the reaction part 40. As a result, a surface tension being a driving force moving fluid is increased to secure a necessary flow rate.
[10] However, in the first method, a configuration of a chip is complicated, thereby increasing manufacturing time and cost and making a checking procedure complicated. The second method has a disadvantage that it increases a term reducing a flow rate of the fluid, such as the Poiseuille pressure, in proportion to the increase of the surface tension. In this way, both of the first method and the second method are undesirable.
[11] Moreover, in the conventional chip for analyzing fluids in which the fluid sample is flowed through by a surface tension between the inner walls 22a, 22b, 22c, and 22d of the channel 22 and the fluid sample, as shown in FIG. 4, the fluid sample 50 flows at a relatively high speed in corner parts of the inner walls 22a, 22b, 22c, and 22d of the channel 22. This causes a flow rate in a center part of the fluid sample 50 not to keep up with that in each corner part, with the result that a bubble 51 forms in the center part of the fluid sample 50, as shown in FIG. 5. The fluid does not react in the part in which the bubble 51 forms. This causes serious problems in checking the fluid sample such as increase of measurement errors.
[12]
Disclosure of Invention
Technical Problem
[13] The present invention has been made in view of the above problems, and it is an object of the present invention to provide a chip for analyzing fluids capable of suppressing the occurrence of a bubble in a fluid sample by causing the fluid sample to uniformly flow inside a channel.
[14] It is another object of the present invention to provide a chip for analyzing fluids in which a fluid flow channel that enables securing a sufficient flow rate for a washing procedure in order to remove floating labels.
[15] It is another object of the present invention to provide a chip for analyzing fluids which may be simply structured at low cost.
[16] It is another object of the present invention to provide a chip for analyzing fluids that may reduce measurement errors.
[17] Additional objects will be more apparent by those skilled in the art to which the present invention pertains according to the specification. Technical Solution
[18] Prior to a description of the present invention, terms used in the present invention will be explained. As used herein, the term "channel" includes a form which has at least one open side. As used herein, the term "free boundary" means a flow surface of fluid not in contact with an inner wall of a channel. As used herein, the term "forward direction" means a flow direction of fluid loaded through a fluid loading hole before the fluid changes direction of a passage. As used herein, the term "reverse direction" means a flow direction of fluid loaded through a fluid loading hole after the fluid changes direction of a passage.
[19] In accordance with an exemplary embodiment of the present invention, there is provided a chip for analyzing fluids comprising: a body; a fluid loading hole formed in one end of the body; a passage switching portion formed in the other end of the body; and a passage formed inside the body, including a first channel extending from the fluid loading hole to the passage switching portion to have a first depth, and second channels being open against the first channel and parallel with the first channel to have a second depth, wherein the second depth is greater than the first depth from the fluid loading hole to the one position below the fluid loading hole, and is reduced from one position below the fluid loading hole to the passage switching portion to have the same height as that of the first depth in the passage switching portion.
[20] By this structure, the fluid sample uniformly flows through the first channel to suppress the occurrence of bubbles. Further, the fluid reaching a passage switching portion flows through the second channel, so that a free boundary of the fluid sample is
damaged in an adjacent part of a passage switching portion of the first channel to secure a flow rate required for washing.
[21] There is also provided a chip for analyzing fluids comprising: a body; a fluid loading hole formed in one end of the body; a passage switching portion formed in the other end of the body; and a passage formed inside the body to communicate with the fluid loading hole, the passage including a first channel extending from the fluid loading hole to the passage switching portion to have a first depth, second channels being open against the first channel parallel with the first channel to have a second depth, and third channels being open against the second channels parallel with the second channels to have a third depth, wherein the second depth is greater than the first depth from an end of the fluid loading hole to the one position below the fluid loading hole, and is reduced from one position below the fluid loading hole to the passage switching portion to have the same height as that of the first depth in the passage switching portion, and the third depth is less than or equal to a depth in the one position below the fluid loading hole.
[22] By this construction, the fluid sample may uniformly flow through the second channel.
[23] In an embodiment of the present invention, the second channels are formed in both sides of the first channel. This enables a flow rate of the fluid sample for washing to be stably secured.
[24] In the embodiment, the opposite sides of the second channels to the first channel are opened. In other embodiment, the opposite sides of the second channels to the first channel are opened against the one position below the fluid loading hole to the passage switching portion.
[25] Under this arrangement, the fluid sample may uniformly flow through the second channels.
[26] In an embodiment of the present invention, the second depth is constant from the fluid loading hole to the one position below the fluid loading hole. In the embodiment, the second depth is continuously reduced from the one position below the fluid loading hole to the passage switching portion. In the embodiment, the second depth is linearly reduced from the one position below the fluid loading hole to the passage switching portion. In the embodiment, the second depth is discontinuously reduced from the one position below the fluid loading hole to the passage switching portion. In the embodiment, the one position below the fluid loading hole is in a downstream of a reaction part of the fluid sample and a probe. The chip for analyzing fluids further comprises a side wall formed through a part of a passage from the fluid loading hole to the passage switching portion for blocking the first channel against the second channels.
[27] Under this arrangement, a flow rate of the fluid sample may be controlled.
Advantageous Effects
[28] According to the present invention, a sufficient flow rate may be secured in a washing procedure for removing floating labels by a cheap and simple structure. A fluid sample may uniformly flow to suppress the occurrence of bubbles in the fluid sample, thereby enabling a significant reduction in measurement errors.
Brief Description of Drawings [29] The objects, features and advantages of the present invention will be more apparent from the following detailed description in conjunction with the accompanying drawings, in which: [30] FIG. 1 is a schematic perspective view illustrating a conventional chip for analyzing fluids;
[31] FIG. 2 is a transverse sectional view of the chip for analyzing fluids shown in FIG. 1;
[32] FIG. 3 is a vertical sectional view of the chip for analyzing fluids shown in FIG. 1 ;
[33] FIG. 4 is a schematic view illustrating a flow shape of a fluid sample inside a channel of the conventional chip for analyzing fluids;
[34] FIG. 5 is a view illustrating the occurrence of a bubble in a channel of the conventional chip for analyzing fluids; [35] FIG. 6 is an exploded perspective view schematically illustrating a chip for analyzing fluids in accordance with an embodiment of the present invention; [36] FIG. 7 is a plan view illustrating a lower plate of the chip for analyzing fluids shown in FIG. 6; [37] FIG. 8 is a side cross-sectional view illustrating an engagement state of the chip shown in FIG. 6; [38] FIG. 9 is an exploded perspective view schematically illustrating a chip for analyzing fluids in accordance with another embodiment of the present invention; [39] FIG. 10 and FIG. 11 are views illustrating an alternative embodiment of a slope portion of the present invention;
[40] FIG. 12 is a cross-sectional view taken along line A-A of FIG. 18;
[41] FIG. 13 and FIG. 14 are schematic views illustrating a flow state of a fluid sample by steps inside a channel of the chip for analyzing fluids in accordance with an embodiment of the present invention; [42] FIG. 15 is a schematic view illustrating a flow shape of a fluid sample by steps inside a channel of the chip for analyzing fluids in accordance with an embodiment of the present invention; and [43] FIG. 16 is an exploded perspective view schematically illustrating a chip for analyzing fluids without a third channel in accordance with an embodiment of the
present invention. [44]
Mode for the Invention
[45] Hereinafter, exemplary embodiments of the present invention are described in detail with reference to the accompanying drawings. The same reference numerals are used throughout the drawings to refer to the same or like parts. Detailed descriptions of well-known functions and structures incorporated herein may be omitted to avoid obscuring the subject matter of the present invention.
[46] <constitution>
[47] FIG. 6 is an exploded perspective view schematically illustrating a chip 10 for analyzing fluids in accordance with an embodiment of the present invention. As shown in FIG. 6, the chip 10 for analyzing fluids in accordance with an embodiment of the present invention includes a body 100 defining a passage therein through which a fluid sample may flow. As shown in FIG. 6, it is preferred that the body 100 is composed of an engagement structure of an upper plate 110 and a lower plate 120. A fluid loading hole 130 for loading the fluid sample is formed in the upper plate 110. Since shaping portions are complementarily formed on the upper plate 110 and the lower plate 102, respectively, a passage is formed by engagement of the upper plate 110 and the lower plate 120. In this case, the fluid sample may flow through the passage. The passage communicates with the fluid loading hole 130.
[48] The passage includes a first channel 141 and second channels 142. The fluid sample flows through the first channel 141. The second channels 142 are formed in both sides of the first channel 141 parallel with the first channel 141. In a preferred embodiment, the passage further has third channels 143 formed parallel with the second channels 142. As described below, the third channels 143 form a free boundary in a side of a reverse direction flow flowing from a passage switching portion 160 to the fluid loading hole 130. Accordingly, as an alternative embodiment, as shown in FIG. 16, a side of the lower plate 120 is open against a part of the reverse direction flow to obtain the same effect. In the preferred embodiment, the second channels 142 are provided in both sides of the first channel 141, respectively. The third channels 143 are provided in respective sides of the second channels 142.
[49] FIG. 12 is a cross-sectional view taken along line A-A of FIG. 18. As illustrated in
FIG. 12, the first channel 141 is defined by an upper inner wall 111 and a lower inner wall 112a. The second channels 142 is defined by the upper inner wall 111, first and second lower inner walls 112b and 112b' and a first sidewall 114. The third channels 143 are defined by the upper inner wall 111, the first lower inner wall 112b, and the second side wall 113. In this case, the first side wall 114 has a height lower than that of
the second side wall 113 so that the first channel 141 and the second channels 142 may be open against each other since there are no inner walls therebetween. However, it is unnecessary to open the first channel 141 and the second channels 142 against each other through a whole flow passage of the fluid sample. As shown in FIG. 9, according to a control requirement of the flow rate of the fluid sample, the first channel 141 and the second channels 142 may be blocked against each other by an inner wall 150 partially formed through a part of the flow passage of the fluid sample. Accordingly, the first channel 141 and the second channels 142 may be closed against each other in a part of the flow passage of the fluid sample. The number, installation position, a shape, and the like of the inner wall 150 may be suitably selected depending on a flow control purpose of the fluid sample.
[50] The second channels 142 and the third channels 143 are intrinsically open against each other but are not separated from each other by side walls. The first channel 141, the second channels 142, and the third channels 143 extend from an end of the fluid loading hole 130 side to a passage switching portion 160 as explained below. The first channel 141 forms a passage through which the fluid sample loaded through the fluid loading hole 130 substantially flows. A width and a depth of the first channel 141 have sufficient sizes to produce surface tension required to cause the fluid sample to flow.
[51] Meanwhile, a depth h of each second channel 142 is preferably formed to be greater than a depth h of the first channel 141. A connection part of the first channel 141 and the second channel 142 is formed as a sloped portion of a sufficient angle so that the fluid sample flowing through the first channel 141 forms a free boundary in a side of the second channel 142. In the preferred embodiment, a sloped angle of the sloped portion is 90 .
[52] The depth h of the second channel 142 is gradually reduced from one position 170 below the fluid loading hole 130, and becomes identical with the depth h of the first channel 141 in the passage switch portion 160 as explained below. Namely, the first channel 141 and the second channels 142 are joined together in the passage switching portion 160 to define one channel.
[53] The position 170 in which the depth h of the second channel 142 starts to be reduced may be suitably selected in consideration of a desired flow amount and flow rate of the fluid sample. It is preferred that the position 170 is in a downstream of a reaction part of the fluid sample and a probe as described later. It is shown that respective depths of second right and left channels 142 are reduced from the same position 170. However, the present invention is not limited thereto. It is preferred that the height of the second channel 142 is maintained constant in remaining parts. However, the present invention is not limited thereto. To meet the requirements, it is readily apparent to those skilled in the art to which the present invention pertains that the height of the second channel
142 may be formed as a suitable profile. The height of the second channel 142 as shown in drawings is reduced to form first, second, and third stepped portions 180b, 181b, and 182b in the position 170. However, the first, second, and third stepped portions 180b, 181b, and 182b may be removed.
[54] FIG. 10 and FIG. 11 show views in which the depth of the second channel 142 is reduced in different patterns. In FIG. 8, the depth of the second channel 142 is reduced in a linear pattern 180a. In FIG. 10, the depth h of the second channel 142 is reduced in a concave curve pattern (exponential pattern) 181a. In FIG. 11, the depth of the second channel 142 is discontinuously reduced in a step function pattern 182a. It is readily apparent to those skilled in the art that different reduction patterns may be used.
[55] A depth of the third channel 143 is less than the least depth of the second channel
142, namely, a depth in one position 170 in below the fluid loading hole on the whole.
[56] Operation
[57] Hereinafter, an operation of the chip 10 for analyzing fluids in accordance with an embodiment of the present invention constructed as above will be described.
[58] FIG. 13 is a view showing a flow state of a fluid sample immediately after the fluid sample is loaded on the chip 10 for analyzing fluids through a fluid loading hole 130 in accordance with an embodiment of the present invention. For the purpose of illustration, only the fluid sample 190 flowing through the first channel 141 is shown.
[59] As shown in FIG. 13, so as to detect an analysis target material included in the fluid sample, when the fluid sample is loaded through the fluid loading hole 130, it moves as shown by an arrow due to surface tension occurring between the fluid sample 119 and upper and lower inner walls 111 and 112a of the first channel 141.
[60] When the fluid sample 119 moves along the first channel 141, because the first channel 141 and the second channels 142 are open against each other, and a depth h of the first channel 141 is less than that h of each second channel 142, right and left sides 192 of the fluid sample 190 define internally concave free boundaries. Meanwhile, since surface tension occurs in parts of the fluid sample 190 contacting with the upper inner wall 111 and the lower inner wall 112a of the first channel 141, a free boundary formed in a front portion 191 of the fluid sample 190 has a concave shape toward an upstream thereof. Since surface tension in a center part of the fluid sample 190 is increased as compared with both sides thereof due to opening between the first channel 141 and the second channels 142, the front portion 191 of the fluid sample 190 has a center part of a convex shape. As the result of complex factors, the front portion 191 of the fluid sample 190 has a free boundary of a horse saddle shape as shown in FIG. 15.
[61] In the meantime, the flowing fluid sample 190 passes through a conjugation part 230 disposed below the fluid loading hole 130. In this case, the analysis target material included in the fluid sample 190 is generally engaged with a label with a fluorescent
material to be detected through an optical measurement.
[62] Next, the fluid sample 190 passes through a reaction part 240 disposed in a downstream of the conjugation part 230. In this case, the analysis target material conjugated with the label reacts and engages with a probe, which is fixed to the first channel 141.
[63] By surface tension between the fluid sample 190 and the upper and lower inner walls
111 and 112a, the fluid sample 190 passes through the reaction part 240 and then moves to a passage switching portion 160. When a front portion 191 of the fluid sample 190 reaches the passage switching portion 160, the fluid sample 190 flows from right and left sides of the passage switching portion 160 to a second channel 142. Thereafter, the fluid sample 190 reversely flows to the fluid loading hole 130 side along a sloped portion of the second channel 142.
[64] Meanwhile, after the fluid sample 190 changes a passage in the passage switching portion 160, in the moment it reversely flows to the fluid loading hole 130 side, first parts (flowing parts in a reverse direction) of the fluid sample 190 flowing to the fluid loading hole 130 and second parts (flowing parts in a forward direction) thereof flowing to the passage switching portion 160 become adjacent to each other. Accordingly, surface tension occurs between the first parts and the second parts, such that a side free boundary present in the flowing parts in a forward direction is broken. Due to breakdown of the side free boundary, the surface tension between the flowing parts in a forward direction and the flowing parts in a reverse direction occurs even in a front position of the passage switching portion 160. As a result, the breakdown of the side free boundary is sequentially progressed in a direction of the fluid loading hole 130 as a domino phenomenon.
[65] Flow variation of the fluid sample due to the breakdown of the free boundary leads to an increase in a flow rate of the fluid sample in the reaction part, thereby securing a flow rate required for washing.
[66] Meanwhile, in a flow in the reverse direction to the fluid loading hole 130 side along the slope portion of the second channel 142, the flow due to stepped portions 180b, 181b, and 182b present in the position 180 is terminated in the position 180. Since a side not adjacent to the first channel 141 of the slope portion of the second channel 142 is open against a third channel, a free boundary is formed in a side of the third channel of the flowing parts in a reverse direction to uniformly form the flow.
Next Patent: PLASMA DISPLAY PANEL AND PROCESS OF MANUFACTURING THE SAME