JP2919927B2 - Improved mechanical cleaning collision mixing type mixing module - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention discharges a liquid A and a liquid B of a two-liquid mixed-curable resin such as urethane, epoxy and unsaturated polyester from a discharge port, and employs a collision mixing method. This improvement relates to a collision-mixing type mixing module (a part integrally formed with a discharge chamber (orifice) for liquid A and liquid B and a mixing chamber for collision-mixing the two liquids) used for mixing and spraying or injection molding. At the start and end of discharge
It is possible to mix the components while maintaining the mixing ratio of the components at the set value, and it is possible to mold without discarding the liquid that does not match the mixing ratio at the start and end (liquid drainage) and stable physical properties And a mixing module for spraying and casting, which can improve the spray condition in the case of spray molding.

In the present specification, the liquid A indicates one liquid of the two-liquid mixed-curable resin, and the liquid B indicates the other liquid.

[Conventional technology]

When molding a two-component fast-curing material with a high reaction rate,
Usually, a collision mixing method is used. This is because mechanical mixing and static mixing do not have sufficient time for cleaning the mixing chamber due to the rapid reaction. The collision mixing method has a feature that the cleaning of the mixing chamber can be performed in a short time by a method of mechanically cleaning the mixing chamber by taking in and out a rod after discharging the mixed liquid, or by using a solvent or air.

Examples of mechanically-cleaning collision mixing heads for mechanically moving rods in and out include D-Gun, GX-7 gun, and RIM (reaction injection molding) heads for spraying and injecting heads of Gasmer, USA. Examples include Toho Kikai, Klaus Muffei, and Canon. In the case of the D-gun, rectangular holes are opened at the top and bottom of the mixing chamber on both sides of the integrated mixing chamber, one at a time, and the liquid discharged into the mixing chamber is ejected after mixing while swirling, Used for spraying or pouring. The problem with this gun is that the number of holes is one each, and in the case of a highly viscous liquid, etc., the mixing characteristics deteriorate, and since the mixing of the two liquids is mainly due to rotational movement, the mixed liquid ejected from the head In particular, in the case of spray molding, the spray state (pattern) is deformed and a density difference occurs. For this reason, when performing the spraying operation, it is necessary to adjust the length of the mixing chamber by changing the retreat position of the valving rod in accordance with the set conditions each time the molding operation is performed.

In the case of the GX-7 gun, it has an integrated mixing module structure, and discharge is A
The liquid is discharged from the front and the liquid B is discharged from the rear. Since the discharge angles are all perpendicular to the rod, there is no direct collision. Therefore, when the rod retreats and the liquid is ejected, the liquid A in the front part is always ejected independently into the mixing chamber first and then the liquid B is ejected. Since the mixed mixture is discharged, a draining operation is required. Further, the same occurs at the time of termination, and the liquid needs to be drained. In the case of spray molding, it is necessary to start spraying (draining) the gun at a place other than the object first at the time of molding, and then spray it onto a mold, etc. Similarly, at the end, after moving the gun from the surface of the molded article to another In addition, the workability is reduced due to the stoppage, and the yield is poor. In the case of injection molding, the same draining operation as in spraying is required. In addition, if the work is not performed reliably, the physical properties are reduced due to the change in the mixing ratio.

The heads used for RIM molding are usually one on each side.
Many types have two orifices and directly collide and mix two liquids.There is a problem with the mixing characteristics. At the same time as installing a remixing auxiliary device such as an "after mixer" or "film gate" on the mold side, The last mixture is designed to be used as a relief part or left in the after-mixer part, and measures are taken to prevent the above-mentioned inappropriate mixture from entering the product, and to deal with variations in the mixing ratio that occurs at the start and end of discharge. doing.

[Problems to be solved by the invention]

When the liquid A and liquid B of a two-component mixed-curable resin such as urethane, epoxy, and unsaturated polyester are discharged from the discharge port and sprayed or injected by a collision mixing method, as described above, the conventional mixing methods are various. Of the present invention, the present inventors can perform molding without discarding the liquid at the start and end of discharge (liquid drainage), and at the same time, have stable physical properties and a good spray condition in the case of spray molding. It was studied to determine a mixing module for spraying and casting in which (pattern) was obtained.

[Means for solving the problem]

When the cleaning characteristics of the head of the collision mixing type are considered, the air cleaning type and the solvent cleaning type cannot be completely cleaned, and the mixture is deposited on the mixing chamber and the nozzle portion with the number of uses, so that the mixing characteristics change. For this reason, the spray condition (pattern) changes in spray molding. Therefore, a mechanical cleaning method is reliable, and there is little change and decrease in mixing efficiency. In order to always maintain the mixing ratio at the start and at the end with the machine washing method, it is necessary to open the orifices of the A liquid and the B liquid at the same time, and it is necessary to keep both orifices on the same circumference. This is a mandatory requirement. This makes it possible to perform molding without discarding the liquid at the start and end of discharge (liquid drainage). In the case of impingement mixing, orifice size accuracy and location accuracy are important factors and affect mixing characteristics. Therefore, by forming the orifices for the liquid A and the liquid B as an integrally molded product, it is possible to prevent the mixing property from varying. It is extremely effective to increase the chance of contact between the two liquids in order to improve the mixing characteristics and obtain stable physical properties. Specifically, the number of orifices and / or the number of orifices used in the raw material are increased to two or more. ± 50% of compounding ratio
To design within. When materials having different mixing ratios are used, it is preferable to adjust the number of orifices from the area in order to improve the mixing characteristics. When the viscosity of the raw materials used is the same, the number and area of the orifices may be the same,
In practice, the viscosities of the two liquids are often different, and the discharge of the high-viscosity raw material tends to be delayed. Although it is possible to adjust the viscosity by providing a temperature difference between the two liquids, it is effective to slightly change the orifice size to increase the working width during molding. Usually, this variation range corresponds to an increase or decrease within ± 50%. Furthermore, in order to obtain a favorable spraying state during spray molding, it is an important element that the mixing of the two liquids is mainly from collision by mixing only by rotation, and that no rotation remains in the mixed liquid. That is, the mixing chamber portion where the two liquids collide is a module that is integrally formed. (1) The liquid A and the liquid B each have two or more discharge ports (orifices). (2) The liquids A and B The positions of the liquid discharge ports are on the same circumference. (3) Both or one of the liquids A and B is discharged linearly toward the center of the mixing chamber. (4) The liquids A and B The design is such that the ratio of the total opening area of the liquid discharge ports is within ± 50% of the mixing ratio of the liquid A and the liquid B, so that the mixing ratio does not change at the start and the end of the discharge, and the liquid needs to be drained. A mixing module that does not need to be manufactured can be manufactured. In addition, since the mixing characteristics of this module are also improved, it is possible to stabilize the physical properties and obtain a good spray condition in the case of spray molding.

Here, “within ± 50% of the mixing ratio of the liquid A and the liquid B” means, for example, when the mixing ratio of the liquid A and the liquid B is 1: 2, the value of this ratio is 1/2, that is, , 0.5, so "±
"Within 50%" means in the range of 0.25 to 0.75, that is, 1: 4 to
3: 4 range.

The mechanical cleaning type collision mixing type mixing apparatus having the structure according to the present design can be used for connecting a nozzle to the tip of the head for spray head, casting pore head and injection, and also for reaction injection. However, in view of the liquid sealing property and the control of the spray pattern, the gas module GX-7 type mixing module having orifices uniformly arranged on the circumference has a high degree of freedom in design and is suitable. The liquid used may be changed to a one-way type instead of a circulating type, and a fixed head type with good control of the liquid temperature and a hand-held gun type with a small size may be used.

As an example of the high-pressure two-liquid discharge machine used for the molding of the present invention, any type can be used without particular limitation as long as it can raise the liquid pressure to about 100 kg / cm ² . As actual examples, THD-2K manufactured by Toray Engineering Co., Ltd. using a gear pump as a pump, NR-230 high pressure polyurethane foaming machine manufactured by Toho Machinery Co., Ltd. using an axial piston pump, and Gasmer Co., Ltd. using a plunger pump ( USA)
H-2000 and T-3H of Glasscraft (USA).

〔Example〕

 Hereinafter, the present invention will be described with reference to examples.

The spray type head is most suitable for examining the mixing performance of the mixing head and the state of the discharged liquid,
The following examples show the results of studies with a spray head. Casting and pouring heads can be made and used with similar designs.

(Explanation of terms) (1) Spray condition (pattern): The following items were visually observed and the results were shown.

・ Concentration distribution: concentration difference of particles ejected from the gun, straining, etc. ・ Particle size: size of particles ejected from the gun, confirmation of atomization status ・ Shape: shape, deformation of ejected material sprayed on the target (2) Tack-free time: The shortest time during which the surface of the sprayed or injected material is lightly touched with a finger and the material does not transfer to the finger.

(3) Stripe pattern on the surface: A situation in which a poorly mixed portion remains as a striped pattern when the mixing ratio or mixing characteristics of the two liquids is poor.

(3) Surface properties: Spray-molded on a polypropylene plate to a thickness of about 2 mm, and the smoothness of the surface and the presence or absence of pinholes were examined.

(4) Physical property test: Measured at 23 ° C according to JIS K-6301.
After curing for one week in a condition of 55% humidity. (Molding material) A rim spray (a quick-curing two-part urethane spray material manufactured by Mitsui Toatsu Chemicals) was used. The following two brands having different mixing ratios and viscosities were used.

In each case, a quick-curing material reacts and cures immediately after spraying, so that an impingement mixing gun is indispensable for mixing.

Liquid A: Isocyanate component [The main ingredient is a modified product of diphenylmethane diisocyanate (MDI-PH), Mitsui Toatsu Chemicals] Liquid B: Resin component (High-pressure two-liquid discharge machine) US Gasmer H-2000 type did. This machine is a one-way type that hydraulically drives a single-shaft, double-action plunger pump, and can be used for injection and spraying. The liquid pressure can be raised to 2000 psi (about 140 kg / cm ² ), and the liquid temperature can be set separately for Liquid A and Liquid B.

 Hereinafter, the present invention will be described in detail with reference to the drawings and embodiments.

FIGS. 1 and 2 show the modified GX- used in Example-1.
FIG. 3 is a sectional view and a front view showing the structure of a mixing module for 7 guns, and FIGS. 3 and 4 show an improved GX used in Example-2.
FIGS. 5 and 6 are sectional and front views showing another modified GX-7 gun mixing module used in Example-3, and FIG. 7 and 8 are side and front sectional views showing an improved mixing module for a D-gun shown in Example-4.

In the figure, 1 is a mixing module, 2 is a balving
1a is an inflow hole for liquid A, 1b is an inflow hole for liquid B,
Reference numeral 1c denotes an outlet for the mixed solution.

Example 1 As a spray head, a GX-7 gun of a mechanical cleaning method manufactured by Gasmer was used, and a mixing module was shown in FIGS. 1 and 2. The schematic diagram in Table 2 shows the discharge angles of the A liquid and the B liquid into the mixing chamber and the collision angles of these two liquids. Both the number and the area of the orifices of the liquid A and the liquid B were designed for A: B = 1: 2 which is the same as the volume ratio of the raw materials. The two orifices for liquid A (isocyanate component) are 180 degrees at each other and the orifices for liquid B (resin component) are 90 degrees at each other.
The two liquids were opened so that the two liquids were linearly directed to the center of the mixing chamber, and the positions of the discharge ports were on the same circumference. That is, the two liquids are mixed in a state where no rotational movement occurs. The diameter of all the orifices was 0.406 mm, and the diameter of the mixing chamber was 3.175 mm. The material was a polyacetal resin (Delrin, a trademark of Du Pont) in consideration of the abrasion resistance and liquid sealing properties due to repeated use. A spray tip (# 212: fan-shaped pattern) was attached to the tip of the gun for molding. The raw material used is Rim Spray PD-450 (Solution A: Solution B = 1: 2 volume ratio), the liquid temperature is 50 ° C for Liquid A, 65 ° C for Liquid B, and the discharge pressure is 112kg / cm ² respectively. The condition was 120 kg / cm ² . As a result, as shown in Table 2, the tack-free time was 9 to 11 seconds, and the setting was fast, and the tack disappeared rapidly as the setting progressed. Since the liquid A and the liquid B were ejected in a state of being mixed at a predetermined mixing ratio from the start of the discharge, no stripe pattern was observed when the mixing ratio was out of order or the mixing was poor. Further, at the end of the molding, it was possible to carry out molding without discarding the liquid (liquid drainage). When a 2 mm thick sheet was molded for measuring physical properties, the yield was as good as 90%.
Observation of the spray condition (pattern) revealed that the concentration distribution was uniform, the particle size was fine, the shape was fan-shaped and normal, and no deformation or the like was observed. The surface of the molded product was smooth and no irregularities were observed. There is enough curability,
The physical property test results of the created sheet are excellent in hardness, modulus, tensile strength, elongation and tear strength,
It also showed that the mixing characteristics were good.

Example 2 A GX-7 gun was used in the same manner as in Example 1, and the mixing module shown in the sectional view and the front view of FIG. 3 and FIG. 4 was used. In addition, Table 2 shows a schematic diagram of the flow direction of the liquid A and the liquid B. The number and area ratio of the orifices were the same as the mixing ratio of the raw materials, ie, liquid A: liquid B = 1: 1. The four orifices for liquid A (isocyanate component) are opened at an angle of 90 degrees to each other, and the liquid is ejected linearly toward the center of the mixing chamber. Liquid B (resin component)
The four orifices were designed such that the positions of the holes were 90 degrees with each other, and four holes were opened. The discharge angle of the liquid was the same as that of the liquid A, and the two liquids were designed so as not to cause rotational movement. The diameter of all the orifices was 0.406 mm, and the diameter of the mixing chamber was 3.175 mm.
Spray tip at tip of gun (# 212: fan-shaped pattern)
And molding was performed.

The raw materials were rim spray PD-190 (A: B liquid = 1: 1 volume ratio). The liquid temperature was 65 ° C for Liquid A, 50 ° C for Liquid B, and the discharge pressure was 116kg / cm ² respectively. The condition was 108 kg / cm ² . As can be seen from Table 2, the tack-free time was 12 to 14 seconds, which was fast curing, the tack disappeared quickly, and the liquid A and the liquid B were mixed from the start at the same time as in Example 1. The mixture was discharged in a mixed state at a ratio, and no stripe pattern observed when the mixing ratio was out of order or when mixing was poor, and molding could be performed without drainage. Observation of the spray condition (pattern) revealed that the concentration distribution was uniform, the particle size was fine, the shape was fan-shaped and normal, and no deformation was observed. The surface of the molded product was smooth and no irregularities were observed. The curability was sufficient, and the physical property test results of the prepared sheet showed that all of the hardness, modulus, tensile strength, elongation, and tear strength were excellent, and that the mixing properties were also good.

Example 3 The same GX-7 gun as that of Example 1 was used, and the mixing module having the cross-sectional view and the front view shown in FIGS. 5 and 6 was used. The number and area ratio of the orifices were designed to be A: B = 1: 1, and as shown in the schematic diagram of Table-2,
The four orifices for the liquid (isocyanate component) are opened with the positions of the holes at 90 degrees to each other, the discharge angle to the mixing chamber is the direction in which the liquid rotates, and the orifices for the liquid B (resin component) are 4 with the position of 90 degrees
The liquid was ejected, and the discharge angle of the liquid was such that no rotational movement occurred on a line toward the center of the mixing chamber. That is, the design is such that mixing is performed in a state where only the A component rotates and the B component does not rotate. The diameter of all the orifices was 0.406 mm, and the diameter of the mixing chamber was 3.175 mm.
Spray tip at tip of gun (# 212: fan-shaped pattern)
And molding was performed.

The raw materials used were rim spray PD-190 (liquid A: liquid B = 1: 1 volume ratio), the liquid temperature was 65 ° C for liquid A, 50 ° C for liquid B, and the discharge pressure was 112 kg / cm ² and 106 kg /, respectively. cm ² conditions. As shown in Table 2, the tack-free time was 12
The curing time was as fast as 1414 seconds, no stripe pattern was observed at the start and end of the jetting, and molding could be performed without draining. Observation of the spray condition (pattern) revealed that the concentration distribution was uniform, the particle size was fine, the shape was fan-shaped and normal, and no deformation was observed. The surface of the molded product was smooth and no irregularities were observed. The curability was sufficient, and the physical property test results of the prepared sheet showed that all of the hardness, modulus, tensile strength, elongation, and tear strength were excellent, and that the mixing properties were also good.

Example-4 A D-Gun manufactured by Gasmer Co. was used, and the mixing module had the structure shown in FIG. 7 (side sectional view) and FIG. 8 (front sectional view), and the number and area ratio of the orifices were A liquid: B. Liquid =
The one designed at 1: 1 was used. The orifice for liquid A (isocyanate component) and the orifice for liquid B (resin component) are opened at three sides each, and as shown in Table-2, the discharge angles of the liquid are all at the center of the mixing chamber. The two liquids collided and collided with each other directly.

The size of the orifice was 0.15 mm × 2 mm, and the diameter of the mixing chamber was 1.32 mm. The spray tip cannot be mounted on the tip of the gun. Raw material is rim spray
Using PD-190 (Solution A: Solution B = 1: 1 volume ratio)
65 ° C., B solution was 50 ° C., and each condition of 74 kg / cm ² and 73kg / cm ² the pressure during jetting (for withstand voltage of the cancer of 70kg / cm ^2). As shown in Table-2, the tack-free time was 13-16 seconds and the setting was fast, and A
The component and the B component were discharged in a state of being mixed at a predetermined mixing ratio, and there was no stripe pattern observed when the mixing ratio was out of order or when mixing was poor, and it was recognized that the mixing characteristics were good.
Further, since the mixing of the two liquids was caused by direct collision, no rotational movement was left in the liquids and the spraying condition was good. Although the surface of the molded product was slightly uneven, it was at an excellent level without any problem in practical use.
The curability was sufficient, and the physical property test results of the prepared sheet showed that there was no problem in any of hardness, modulus, tensile strength, elongation and tear strength, and that the mixing properties were good.

Comparative Example-1 A GX-7 gun was used in the same manner as in Example-1, and the same mixing module # 10 type manufactured by Gasmer was used. A
Table 2 is a schematic diagram showing the liquid flow directions of the liquid and the B liquid. Two orifices for the main agent (isocyanate component) are open at the front, and two orifices for the resin are open at the back. The structure is such that the liquid is discharged in a flow parallel to the liquid, so that none of the liquids directly collides and no rotation occurs. All orifices had a diameter of 0.194 mm. As shown in Table 2, the discharge rate of the molding test was 5.1 kg / min.
The number is twice as high and the number of Reynolds nozzles is higher, which is more advantageous than Example-1. The spray condition was fine, the particle size was fine, the shape was fan-shaped and normal, but the concentration distribution was dark at the end,
In addition, the lines were uneven and uneven. The tack-free time was 9 to 11 seconds, which was equivalent to that of Example 1, but the liquid A and the liquid B were not mixed at a predetermined mixing ratio from the start of jetting.
At the same time that a striped pattern was observed, the tackiness on the surface was strong and it did not disappear even after a lapse of time. Further, the mixture ejected at the end also had a stripe pattern as in the start, and the tack was strong and sticky at any time. Therefore, in this mixing module, it was impossible to carry out molding without discarding the liquid (liquid drainage). When a 2mm-thick sheet was formed, the drainage rate was 45%.
And about half of Example-1.

In the physical property test results, all items were lower, and the mixing efficiency is considered to be poor.

Comparative Example-2 Mixing module (52L) for D-Gun manufactured by Gasmer
Was used. The schematic diagram showing the liquid flows of the A liquid and the B liquid in this mixing module is as shown in Table-2.
The mixing module has an integrated structure and has one rectangular orifice on each side having the same diameter.
The orifice size is 0.3 × 3 mm, and discharge is performed in the direction that rotation in the same direction occurs in a cylindrical mixing chamber that is machine-cleaned. The machine body and raw materials were the same as in Example-6. As shown in Table 2, the ejection volume was 3.2 kg / min, which was a moderate ejection volume. The cure / reactivity was slightly delayed with a tack-free time of 14 to 18 seconds. Observation of the spraying state revealed that the sheet had poor smoothness and large surface irregularities due to the large particle size. The spray condition showed a difference in the concentration distribution, and the shape was deformed at the same time as the streaks entered the end. This gun was implemented because the position of the rod could be adjusted to change the length of the mixing chamber and change the spray conditions, but the deformation and concentration distribution were not significantly improved. The results of the physical property tests were such that all of the items of hardness, modulus, tensile strength, elongation and tear strength were considerably low and stirring and mixing were not sufficiently performed.

[Effect of the Invention] In the method of mixing the two-component type fast-curing material by the mechanical cleaning type collision mixing, the structure of the present invention, in which the mixing chamber portion where the two liquids collide with each other, is made into an integrally molded product, so that when the discharge starts And at the end, it is possible to secure a predetermined blending ratio, eliminating the need for draining operation,
1) Improvement in yield 2) Stabilization of physical properties of products 3) Improvement in workability can be achieved. In the case of spray molding, the spray condition (pattern) is always stable, and adjustment of working conditions is unnecessary.

[Brief description of the drawings]

1 and 2 show the modified GX-7 used in Example-1.
FIG. 3 is a cross-sectional view and a front view showing the structure of the gun mixing module, and FIGS. 3 and 4 show the modified GX- used in Example-2.
FIG. 5 and FIG. 6 are sectional and front views showing another modified GX-7 gun mixing module used in Example-3, and FIG. FIG. 8 and FIG. 8 show in Example-4.
It is the side and front sectional drawing which shows the improved mixing module for D guns.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B29B 7/76 B05B 7 / 04,15 / 02 B01F 5/02

Claims (1)

(57) [Claims] 1. An apparatus for discharging a liquid A and a liquid B of a two-liquid mixed-curable resin from a discharge port and mixing them by a collision mixing method, wherein a mixing chamber portion for causing the two liquids to collide is provided.
(1) It has two or more discharge ports (orifices) for liquid A and liquid B, respectively. (2) The positions of the liquid A and liquid B discharge ports are the same circumference. (3) Both or either solution A and solution B are discharged linearly toward the center of the mixing chamber. (4) The total opening area ratio of the discharge ports of solution A and solution B is An improved machine-cleaning collision mixing type mixing module, characterized in that the mixing ratio of the liquid A and the liquid B is within ± 50%.