JPS58175637A - Manufacture of stable foamed object - Google Patents

Abstract

PURPOSE:To obtain the foamed object of a stable quality economically, by pouring a main component from the pouring port of the peripheral part of the shaft of a frothing machine for mechanical forth toward the central part of the shaft and a curative in an outer peripheral direction of the shaft. CONSTITUTION:The purpose product is obtained by pouring a main component (R) (e.g., the resin liquid of a urea resin, a urethane resin, etc.) from the pouring port 2 of the peripheral part of the shaft of the frothing machine for mechanical froth toward the central part of the shaft via the place shown by an arrow (R1) and a curative (H) (together with an air for foaming) from the place shown by the arrow (H1) in the outer peripheral direction of the shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for stably producing a foam using a water-soluble or water-dispersible thermosetting resin as a raw material and using a mechanical 70 bath foaming machine. The body has excellent performance as an insulator, saving energy and
Large demand is expected due to the need to conserve resources. In addition, from the perspective of resource conservation, there is an increasing demand for foams with a high expansion ratio.

Conventional methods for producing highly foamed materials include resin foam raw materials, curing agents, and blowing agents that are liquid at room temperature and pressure but vaporize when the temperature rises, or liquid under pressure but at room temperature and pressure. A common method has been to mix a gaseous foaming agent (hereinafter simply referred to as a liquid foaming agent) and then foam and harden the mixture.

However, such a method has the disadvantage that a large amount of foaming agent must be used in order to increase the foaming magnification sound, which increases the cost of producing the foam. In addition, when manufacturing a foam using a liquid foaming agent, the foaming rate differs depending on the temperature of the atmosphere, making quality control difficult. It is easy to cause parts to freeze.

On the other hand, hydrophilic thermosetting resins can be foamed using air as a foaming agent, and in this method, there is almost no volumetric expansion after discharge from a foaming machine, making quality control easy. As described above, there is a strong demand for hydrophilic thermosetting resins because they use air as a blowing agent, so the manufacturing cost is low and workability is good.

In the method of producing foam from hydrophilic thermosetting resin using air as a foaming agent, resin liquid, air, and a curing agent are foamed and cured using a foaming machine. Most preferably, a foaming machine is used. The structure of this mechanical floss foaming machine is shown in FIG.

Conventionally, when injecting each component of base resin (resin liquid) R1 curing agent H5 and foaming air A through the injection port 2 provided around the shaft 1, the shaft part, especially the curing agent inlet part, was frequently clogged, and the composition ratio There were concerns about instability in production and quality due to changes in foam, contamination of gelled substances, reduction in expansion ratio, and reduction in yield. The above problems can be solved by injecting the base agent toward the center of the shaft from the injection port provided at the periphery, and the curing agent alone or together with foaming air toward the outer circumference of the shaft, resulting in a stable foam. This led to the invention of a manufacturing method.

This will be explained using drawings. Figure 1 is Mechanica/l/7
This is a cross-sectional view of the 0-s foaming machine. The mechanical floss foaming machine moves a large number of blades (
It has a structure in which a rotor 5 having projections) 4 rotates, and the blades 4 rotate between the projections together with the rotation of the rotor 5 without contacting the projections 3. The foam raw material injected mainly from the periphery of the supported shaft 1 is mechanically mixed and foamed between the blades 4 and the protrusions 3 to form a foamed state.

2 and 3 are XX' cross-sectional views in FIG. 1. Conventionally, for example, air, curing agent, The main agent was injected toward the center of the shaft. However, as mentioned above, clogging occurred at the curing agent inlet. Therefore, the hardening agent injection port is H8~.

A method of injecting from the cylindrical container portion was also attempted, but this also resulted in curing of the tζ portion, which was inconvenient.

In contrast, the present invention injects air, a hardening agent, and a base agent from the locations indicated by arrows A, Hl, and R in FIGS. Inject towards. At this time, the curing agent H1'f
c May be injected together with air A.

By injecting the curing agent toward the outer circumference, the production and quality of the foam were stably improved.

Examples of the thermosetting resin foam of the present invention include urea resin, phenol resin, and urethane resin.

Next, a more specific explanation will be given with reference to Examples.

Unless otherwise specified, "parts" or "chi" refer to parts by weight or percent by weight.

Examples and Comparative Examples The urea resin initial condensates used in Examples and Comparative Example 1 were produced as follows. By concentrating commercially available urea resin Euroform RIOI (manufactured by Mitsui Toatsu Chemical Co., Ltd.) under reduced pressure, it has a viscosity of 2500 centiboise and a non-volatile content of 73%.
A urea resin initial condensate was obtained. Water was added to this urea resin initial condensate to give a non-volatile content of 52q6, and 1 part of sodium alkyl diphenyl ether disulfonate was added and mixed to 100 parts to obtain Tree (5) bile fluid. On the other hand, as the curing liquid, an aqueous solution containing 2.0% phosphoric acid, 10% resorcinol, and 1% sodium alkyldiphenyl ether disulfonate was used.

In Examples and Comparative Examples, Figures 1 and 3, Figure 1
The mechanical 70s foaming machine (manufactured by Toho Kikai Kogyo ■, model Toho' IM302, shown in Figures and Figure 2) has many protrusions 3 on the inner wall of the cylindrical container, and a large number of stirring blades 4 (protrusions).
A rotor 5 having a rotor 5 is injected into the container (6) (a structure in which it rotates close to the protrusions 3) at a flow rate of a weight ratio of resin liquid and curing liquid of 100/35, and compressed air is injected into the foaming machine. The mixture was continuously injected so as to keep the internal pressure at 35 to 45 kf/cII, and the rotor 5 of the foaming machine was rotated at a rotation speed of 45 Orpm. In the example, as shown in FIGS. 1 and 3, the resin liquid was injected through the inlet R1, the curing liquid was injected through the inlet H1, and the compressed air was injected through the inlet A.

On the other hand, in the comparative example, in FIGS. 1 and 2, compressed air was injected from the resin liquid K I ('2) through the injection port A rather than the curing liquid H2.

Continuous discharge is started through the discharge port 3 of the foaming machine and an injection hose (not shown), and the foam-containing mixture f 30 c is pumped out at regular intervals.
It was cured in an m square cardboard box. Table 1 shows the properties of the obtained foam and the density after drying.

Furthermore, in the example, the foam density reached approximately 17 klf/ln'' when the foam was operated continuously for 8 hours a day, washed with water, and then reused the next day without disassembly and cleaning. Because the properties became somewhat uneven, it became necessary to disassemble and clean it.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a mechanical 70 bath foaming machine. Figure 2 shows lf of the conventional injection method taken along the line XX in Figure 1.
FIG. 3 is an explanatory diagram illustrating an example of the method of the present invention taken along the line XX' in FIG. 1. 1...Shaft, 2...Inlet, 3...Protrusion, 4
...Blade, 5...Rotor, 6...Bearing, A...
Air, H...hardening agent, R...main agent. Patent applicant: Mitsui Toatsu Chemical Co., Ltd. Representative patent attorney: Masaru Inoue Main tube 2 Figure 3

Claims (1)

[Claims] 1. When producing foam using a mechanical floss foaming machine, the main agent is injected toward the center of the shaft from the injection port provided around the shaft, and the curing agent is injected alone or together with air toward the outer circumference of the shaft. 1. A method for producing a water-soluble or water-dispersible thermosetting resin foam, the method comprising injecting a water-soluble or water-dispersible thermosetting resin foam.