JPS6254647B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to cleaning compositions for various molding machines,
More specifically, the object of the present invention is to provide a cleaning composition useful for cleaning extrusion molding machines, injection molding machines, etc. used for molding various synthetic resins. Conventionally, various types of plastics are colored at the same time as they are molded using various molding machines such as extrusion molding machines and injection molding machines. However, when various types of coloring are performed using the same molding machine, the molding machine is changed every time the color is changed. need to be cleaned. These cleaning methods are as follows:
- The method described in Publication No. 7185 and the method of pouring a large amount of uncolored resin into the molding machine when changing colors are used, but with such methods, a large amount of resin is wasted and the molding machine is The operating rate also decreases, which is economically unfavorable. Therefore, there is a need for a method that can clean a molding machine in a short time while using a small amount of resin. As a result of intensive research to satisfy the above-mentioned industry demands, the present inventor discovered that a composition with excellent detergency can be obtained by blending various ingredients, and completed the present invention. did. That is, the present invention provides at least one resin selected from the group consisting of polyethylene, polypropylene, polystyrene, AS resin, ABS resin, polycarbonate resin, polyamide resin, and polyester resin.
thermoplastic resin, at least one inorganic filler selected from the group consisting of calcium carbonate, barium sulfate, magnesium carbonate, talc, silica and alumina, and liquid paraffin, natural paraffin, micro wax, synthetic paraffin, polyethylene wax , higher fatty acids, oxyfatty acids, higher fatty acid amides, alkylenebishigher fatty acid amides, higher fatty acid lower alcohol esters, higher fatty acid polyglycol esters, higher fatty alcohols, higher polyhydric alcohols, polyglycols, polyglycerols, higher fatty acid metal soaps, and various other types. A cleaning composition for a molding machine, comprising at least one lubricant selected from the group consisting of waxes, wherein the inorganic filler accounts for about 30 to 70% by weight, and the lubricant accounts for about 1 to 30% by weight. It is. To explain the present invention in detail, the thermoplastic resin used in the present invention includes polyethylene such as low density LD polyethylene and high density HD polyethylene, polypropylene, polystyrene, AS resin,
ABS resin, polycarbonate resin, polyamide resin, polyester resin, etc., and these thermoplastic resins account for approximately
Preferably, it is used in an amount of 30 to 60% by weight. The inorganic filler used in the present invention acts as a kind of abrasive for the inner wall of the cylinder of the molding machine and the surface of the screw, and preferable examples include:
These include those conventionally called extender pigments and inorganic fillers, such as calcium carbonate, barium sulfate, magnesium carbonate, talc, silica, alumina, and the like. These inorganic fillers are preferably used in an amount of about 30 to 70% by weight of the cleaning composition. If the amount used is less than 30% by weight, the abrasive action of the inorganic filler will be insufficient;
If the amount exceeds 70% by weight, the fluidity of the cleaning composition within the cylinder will decrease, which is not preferable. The lubricant used in the present invention means that if the above-mentioned thermoplastic resin and inorganic filler are used alone, the inorganic filler concentration is too high and the fluidity of the composition is insufficient, and the lubricant tends to adhere to the cylinder wall surface and screw surface. Therefore, this tendency is prevented to prevent the fluidity of the composition within the cylinder and the adhesion to the cylinder wall surface and screw surface. Preferred examples include liquid paraffin, natural paraffin, micro wax, synthetic paraffin, polyethylene wax, higher fatty acid, oxyfatty acid, higher fatty acid amide, alkylene bis higher fatty acid amide, higher fatty acid lower alcohol ester, higher fatty acid polyglycol ester, These lubricants include higher fatty acid alcohols, higher polyhydric alcohols, polyglycols, polyglycerols, higher fatty acid metal soaps, and various waxes, and these lubricants are used in a proportion of about 1 to 30% by weight in the cleaning composition. is preferred. If the amount used is less than 1% by weight, its action as a lubricant will be insufficient, while if it exceeds 30% by weight, the fluidity of the composition will be too high and the inorganic filler will have an abrasive effect on the cylinder wall surface and screw surface. This is not preferable because it reduces the In the present invention, these lubricants can be used alone or in a mixture. When used in a mixture, a lubricant that provides internal lubricity and a lubricant that provides external lubricity (C ₂₈
to _C32 higher fatty acids, paraffin, polyethylene wax, etc.), and the weight ratio of the former to the latter is 1:0.1 to 10, preferably 1:0.5 to 5.
The best effects can be obtained when used at a ratio of The essential components of the cleaning composition of the present invention are as described above, but optional components such as various other additives such as plasticizers, stabilizers, ultraviolet absorbers, and antistatic agents may be simply mixed as necessary. However, it is generally preferable to mix each component, melt-knead it using an extruder, etc., and form it into a pellet before use. When the cleaning composition of the present invention as described above is used as a cleaning agent when producing colored molded articles using an extrusion molding machine or an injection molding machine, it exhibits extremely excellent cleaning properties.
For example, when molding different colored molded products using the same molding machine, conventionally a large amount of uncolored resin was used each time the color was changed, and cleaning took a long time, but the present invention If you use a cleaning agent of
It is possible to achieve the same cleaning effect at 1/10th the size. Next, the present invention will be specifically explained with reference to Examples. Note that parts and percentages in the text are based on weight. Examples 1 to 6 After blending each component in Table 1 below using a mixer,
The mixture was melt-kneaded using a vented 40 mm extruder and formed into pellets to obtain the cleaning composition of the present invention. Note that the numbers in the table represent parts by weight.

[Table] Usage Example 1 (Example of cleaning an injection molding machine) Cleaner compositions obtained in Examples 1 to 6 after injection molding colored resin pellets containing 1% phthalocyanine blue in a 5-ounce injection molding machine. The molded product was injection molded using a material and cleaned, and the amount until the molded product was no longer colored was determined. In addition, the amount of resin required when sweeping was performed under the same conditions using the same uncolored resin as the colored resin was determined.

[Table] Usage example 2 (Example of cleaning an injection molding machine) After extruding a resin blended with 5% phthalocyanine blue using a 30 mm extruder, clean the hopper,
The cleaning compositions obtained in Examples 1 to 6 were extruded and cleaned. Then, the amount of resin required until the extruded product was no longer colored was determined. In addition, the amount of resin required when sweeping was performed under the same conditions using the same uncolored resin as the colored resin was determined.

[Table] As described above, the cleaning composition of the present invention is extremely useful for cleaning various molding machines when changing colors. Note that the cleaning composition of the present invention is useful not only for changing colors, but also for general cleaning. For example, regardless of whether the molding machine is colored or uncolored, if you stop using the molding machine, the molding machine will not cool down rapidly, so the resin remaining in the molding machine will burn or carbonize due to the residual heat of the molding machine. However, by using the cleaning composition of the present invention when restarting the molding machine, these foreign materials can be removed. It can be easily removed and the above problems have been solved.

Claims (1)

[Claims] 1. At least one thermoplastic resin selected from the group consisting of polyethylene, polypropylene, polystyrene, AS resin, ABS resin, polycarbonate resin, polyamide resin, and polyester resin, calcium carbonate, barium sulfate, magnesium carbonate, At least one inorganic filler selected from the group consisting of talc, silica and alumina, and liquid paraffin, natural paraffin, micro wax, synthetic paraffin, polyethylene wax,
Higher fatty acids, oxyfatty acids, higher fatty acid amides,
At least one member selected from the group consisting of alkylene bishigher fatty acid amide, higher fatty acid lower alcohol ester, higher fatty acid polyglycol ester, higher fatty alcohol, higher polyhydric alcohol, polyglycol, polyglycerol, higher fatty acid metal soap, and various waxes. A cleaning composition for a molding machine comprising a lubricant, wherein the inorganic filler accounts for about 30 to 70% by weight and the lubricant accounts for about 1 to 30% by weight. 2. The cleaning composition according to claim 1, which is melt-kneaded and formed into pellets. 3. The cleaning composition according to claim 1, wherein the lubricant comprises an internal lubricant and an external lubricant. 4. The cleaning composition according to claim 3, wherein the ratio of the internal lubricant to the external lubricant is 1:0.1 to 10.