JPH04277060A - Quantitatively discharging method - Google Patents

Abstract

PURPOSE:To avoid the lowering of a discharge amount due to the lowering of a liquid head accompanied by the advance of coating with the elapse of time and to always discharge the liquid agent in a container in a constant discharge amount to the last in a pressure control type discharge apparatus. CONSTITUTION:The lowering of a discharge amount due to the lowering of the liquid head of a stored liquid agent accompanied by the advance of the discharge of the coating solution in a barrel 5 is compensated by successively correcting the pressure of the air supplied by a pressure controller 4 to keep the discharge amount constant.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention aims to prevent a drop in the discharge amount due to a drop in the liquid head in a pressure-controlled discharge device that applies a pattern of a reagent layer and a developing layer on a support layer, for example, in the production of analytical elements, etc. This invention relates to a fixed amount dispensing method that avoids this problem and always maintains a constant dispensing amount.

0002

[Prior art] Various low and high viscosity liquids (instant adhesives,
A so-called dispenser is used as a dispensing device capable of dispensing a fixed amount with high accuracy when dot coating, pattern coating, intermittent small amount dispensing, and small continuous dispensing of oil, flux, solvent). The dispenser includes a so-called pressure-controlled dispenser that applies air pressure to the liquid stored in a container and causes the liquid to be discharged from a discharge part that communicates with the container, and a pressure-controlled dispenser that applies air pressure to the liquid stored in the container and causes the liquid to be discharged from a discharge part that communicates with the container. There is a so-called mono dispenser that is equipped with a mono pump and is powered by a motor to forcibly discharge a liquid agent.

[0003] The use of the dispenser is as follows:
For example, it is effectively used in the field of manufacturing dry analytical elements such as biochemical analytical elements. The analytical element has a reagent layer, other functional layers, and a developing layer layered on top of a transparent support sheet made of polyethylene terephthalate, etc., for example, to develop a sample such as blood or serum. When it is spotted on the layer, it is dispersed in the development layer and then brought into contact with the reagent layer to cause a coloring reaction,
Blood analysis is performed by measuring the process and result of this color change by measuring the reflected light from the analysis element of the light irradiated from the lower surface of the transparent support. Note that the analysis device is
It is commonly known as "dry chemistry".

[0004] In the analytical element, the spreading layer has a thickness of 10 μm.
By spotting about 1 liter of liquid sample, 10
Since it is sufficient for analysis to obtain diffusion of about mmφ, for example, coating the reagent layer and the developing layer over the entire area of a 14 mm x 14 mm element piece is a waste of the coating solution for the reagent and the developing layer. Especially for the above-mentioned reagents, which cost as much as 100 million yen per gram, eliminating waste is of great significance. Therefore, the dispenser is used as a device for applying the reagent and the developing layer to the minimum necessary extent. Application methods include, for example, a method in which the material is applied in dots and circular diffusion is used, and a so-called pattern application method in which a robot moves a dispenser circumferentially to apply the material in a circular manner.

[0005]

[Problems to be Solved by the Invention] Generally, in the case of application using the pressure-controlled dispenser, the discharge amount is adjusted by adjusting the discharge time, the set value of the discharge pressure, and using the needle (
This is done by selecting the nozzle size. However, in the above-mentioned discharge amount adjustment method, in order to cope with a decrease in the discharge amount due to a drop in the liquid head due to a decrease in the amount of coating liquid stored in the cartridge, the needle diameter of the dispenser is made thinner or longer. There is a problem in that it is not possible to ensure a constant ejection amount by simply making the liquid head less susceptible to the drop as much as possible. For example, when discharging a system containing solids, especially a dispersion system, it is necessary to make the needle diameter thicker and shorter, and in this case, it becomes difficult to discharge a fixed amount due to the influence of the lowering of the liquid head.

Therefore, an object of the present invention is to avoid a decrease in the discharge amount due to a drop in the liquid head as coating progresses over time in a pressure-controlled discharge device, and to always discharge a constant discharge amount until the end of the liquid in the container. The object of the present invention is to provide a method for dispensing a fixed amount.

[0007]

[Means for Solving the Problems] The above problem is solved by applying air pressure to a liquid agent stored in a container and discharging the liquid agent from a discharge portion communicating with the container. Compensating for a decrease in the discharge amount due to a decrease in the liquid head of the stored liquid agent by successively correcting the air pressure,
This problem can be solved by keeping the discharge amount constant.

[0008] Alternatively, the ejection amount may be kept constant by sequentially correcting the ejection time.

[0009]

[Operation] In the pressure-controlled dispenser, the relationship between the discharge amount and the discharge time and between the discharge amount and the discharge pressure are as shown in FIGS. 4 and 5, for example. Figure 4 shows the discharge conditions: discharge material: silicone, viscosity: 40,000 cp
s, discharge pressure: 3.0 kgf/cm2, needle diameter: 0
．． The relationship between the discharge amount (mg) and the discharge time (t) when the diameter is 97 mm2 (nominal size 17G) is shown. Also, Figure 5
The discharge conditions are: discharge material: silicone, viscosity: 40000
cps, discharge time: 0.5 sec, needle diameter: 0.9
Discharge amount (mg) for 7mm2 (nominal size 17G)
) and discharge pressure (t).

As can be seen from FIGS. 4 and 5, when other discharge conditions are fixed, the relationships between the discharge amount and the discharge time and between the discharge amount and the discharge pressure are constant, and it is easy to determine this by testing. Be able to understand relationships. Further, the degree of decrease in the discharge amount due to the drop in the liquid head can also be ascertained in advance through a test. Note that the above-mentioned relationship between the discharge amount, discharge pressure, and liquid head can be controlled if a certain relational expression can be derived, and a complex relationship such as a quadratic or cubic curve may be used.

[0011] In the present invention, as described above, the liquid head of the coating liquid in the container as it is discharged is adjusted based on the relationship between the discharge amount, the discharge time, and the discharge pressure, and the degree of decrease in the discharge volume due to a decrease in the liquid head. By successively correcting the discharge pressure, the discharge amount can be kept constant. Also, instead of correcting the discharge pressure,
The ejection amount can also be kept constant by sequentially correcting the ejection time.

0012

EXAMPLES The present invention will be explained in detail below using examples relating to the production of analytical elements. FIG. 1 shows a pattern coating apparatus using a pressure-controlled dispenser, and FIG. 2 shows a procedure for coating onto a support. The pattern coating device includes a discharge device 1 consisting of a discharge section 3 and a pressure controller 4, and a robot 8 that grips a barrel (container) 5 of the discharge section 3 and can freely scan. As the discharge device 1, for example, a commercially available pressure-controlled dispenser manufactured by Iwashita Engineering Co., Ltd. can be used. Further, as the robot 8, Panarobo MN-6310 (ST type) manufactured by Matsushita Electric Industrial Co., Ltd. can be used. During coating, a coating liquid is put into the barrel 5, and the pressure controller 4 sends air through an air tube 7 communicating with the inside of the barrel 5, so that the coating liquid is discharged from the needle 6. The discharge pressure of the air can be freely controlled by the controller 4, and continuous discharge or point discharge is possible as desired.

On the other hand, the analytical element 10 to be manufactured has, for example, a shape of 14 mm x 14 mm, as shown in FIG.
A reagent layer 11, a buffer layer 12, and a developing layer 13 each having a diameter of about 10 mm are sequentially laminated on a polyethylene terephthalate 2 having a thickness (t) of 180 μm. The spreading layer 13 is a layer for diffusing and distributing the dropped sample, and the buffer layer 12 is a layer for spreading and distributing the dropped sample and the reagent layer 1.
A layer for optimally adjusting the color reaction in 1,
The reagent layer 11 is a layer that exhibits a color reaction upon contact with a sample. In order to obtain the analytical element 10, for example, 500
An adhesive layer is coated on the entire surface of a polyethylene terephthalate support 2 measuring mm x 1000 mm using a coating machine such as a blade coater, and the reagent layer 11, buffer layer 12 and spreading layer are coated on this support 2. 13 laminated coating is performed.

At the time of coating, after setting the discharge pressure to a predetermined value and setting the gap G between the support 2 and the needle 6, the robot 8 is operated to form an array with an interval of 14 mm vertically and horizontally as shown in FIG. After applying a pattern with a diameter of 10 mm and completing the laminated coating of the three layers, the analytical element 10 can be obtained by cutting along the cutting line shown by the broken line.

In this embodiment, in order to continue discharging a constant amount until the coating liquid in the barrel 5 is exhausted, coating is performed while sequentially correcting the discharge pressure in accordance with the drop in the liquid head as the coating liquid decreases. I do. The discharge pressure may be corrected by checking the decrease in the coating liquid in the barrel 5 and manually operating the discharge pressure setting range of the controller 4 according to the decrease. Data such as the relationship between the drop in the liquid head and the discharge amount and the relationship between the discharge amount and the discharge pressure can be input in advance, and the discharge pressure can be automatically corrected as the coating progresses.

[0016]

As described in detail above, according to the present invention, in a pressure-controlled discharge device, it is possible to avoid a decrease in the discharge amount due to a drop in the liquid head as the coating progresses, and to maintain a constant discharge amount at all times.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a pattern coating device using a pressure-controlled dispenser.

FIG. 2 is a diagram showing a procedure for coating onto a support.

FIG. 3 is a layer configuration diagram of an analytical element.

FIG. 4 is a diagram showing the relationship between ejection amount and ejection time under predetermined conditions.

FIG. 5 is a diagram showing the relationship between discharge amount and discharge pressure under predetermined conditions.

[Explanation of symbols]

Claims (2)

[Claims] 1. A fixed-quantity dispensing device that applies air pressure to a liquid stored in a container and discharges the liquid from a discharge portion communicating with the container, wherein the liquid is discharged due to a drop in the liquid head of the stored liquid as the discharge progresses. A quantitative dispensing method characterized in that the drop in the amount is compensated for by successively correcting the air pressure to keep the dispensing amount constant. 2. The quantitative dispensing method according to claim 1, wherein the dispensing amount is kept constant by sequentially correcting the dispensing time.