JPS6134104A - Organic impregnant having good stability for metal - Google Patents

Abstract

PURPOSE:To provide an impregnant having an extended stable period in a pot life by adding a metallic chelate compd. to an org. impregnant consisting of a (meth)acrylate, polymn. initiator and polymn. inhibitor. CONSTITUTION:This impregnant for metal consists of the acrylate or methacrylate monomer, polymn. initiator, polym. inhibitor and the metallic chelate compd. as a stabilizer. The characteristic of the impregnant after impregnation is exactly the same as the characteristic of the basic compsn. consisting of the (meth)acrylate monomer and polymn. initiator and polymn. inhibor and only the stable perod in the pot life is extended. The metallic chelate compd. which is the stabilizer refers to ethylenediaminetetraacetic acid, N-hydroxyethyl ethylenediamine N, N', N' trictid acid, etc. which produce a water soluble chelate compd. by binding with metallic ions.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to organic impregnating agents for metals with improved stability. As is already known, a metal impregnating agent is a mixture of a radically polymerizable acrylic ester and/or methacrylic ester monomer that exhibits anaerobic curing properties, a polymerization initiator, and a polymerization inhibitor; The agent is used because it can fill in defects caused by casting or powder metallurgy, etc., and improve the airtightness of parts. Conventionally, impregnation treatment for castings has used an impregnating agent whose main ingredient is sodium silicate as a means of saving cast parts that need to maintain airtightness, but as the quality requirements of parts manufacturers have become higher, Reliability of cast parts treated with soda-based impregnation agents is reduced. The main reason for this is the solid content and curing mechanism of sodium silicate, which tends to cause problems such as uncured impregnating agent flowing out during machining, painting, and assembly processes after treatment.

Known organic impregnating agents have the following characteristics that can overcome the drawbacks of such sodium silicate-based impregnating agents, and their performance after treatment is stable.

■ Compared to sodium silicate impregnation agents, it has a lower viscosity and surface tension, so it penetrates better.

(2) Compared to a sodium silicate impregnation agent, the liquid becomes a solidified product of 100*.

(2) Since the curing (polymerization) temperature is fixed, the change over time after impregnation is very small.

However, compared to the sodium silicate impregnating agent, it has an important drawback in handling during impregnation treatment, in that it cannot withstand long-term use unless it is kept cold.

Generally, the use of known organic impregnating agents requires stainless steel and cooling equipment.

In addition, if the ambient temperature is high during the impregnation process, gelation occurs on the surface of the casting, making cleaning difficult and resulting in poor appearance.

As a result of repeated research to improve the above-mentioned drawbacks, the present inventor found that
It has been found that a composition comprising a radically polymerizable (meth)acrylic acid ester monomer, a polymerization initiator/polymerization inhibitor, and a metal chelate compound can serve as an optimal organic impregnating agent for the purpose of the present invention.

In the organic impregnating agent according to the present invention, the properties after impregnation are (meta)
Compared to the basic composition consisting of an acrylic acid ester monomer and a polymerization initiator/polymerization inhibitor, there is no deterioration at all, and only the stability period during use is increased.

Next, the monomer most suitable for use in the impregnating agent of the present invention is (
It is a meth)acrylic acid ester, and examples include meth)acrylic acid esters.

(meth)acrylic acid 2- and droxyethyl, (meth)acrylic 12-hydroxypropyl, (meth)acrylic I
l! 1゜4butanediol, (meth)acrylic 8!1.
6-hexanediol, glycidyl methacrylate, methacrylic + 1!2-ethylhexyl, alkyl methacrylate, tridecyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, polyethylene glycol dimethacrylate, dimethacrylate-strength poly-10-pyrene glycol, triedyl dimethacrylate Ren glycol, diethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, dimethacrylate l! 16 hexanediol and the like.

Polymerization inhibitors include 0-nitrosophenol, hydroquinone, 4-methoxyphenol, and methoquinone.

Polymerization initiators include peroxy esters, hydroperoxides, diacyl peroxides, and the like.

The metal chelate compound as a stabilizer in the present invention refers to EDT, which combines with metal ions to form a water-soluble chelate compound.
A (ethylenediaminetetraacetic acid), HEEDTA (N
-human 0xyethylethylenediamine N,N',N-triacetic acid), DTPA (diethylenetriamine panacetic acid), T
HPED (N, NN-, N-, tetrakis 2-hydroxypropylethylenediamine), EDDA (ethylenediamine N, N" diacetate m'), HEDPA (1-hydroxyethylidene 1-1. diphosphorus! lj), TTHA
(, t-lyethylenetetramine N, N-, N-, N=
, N-hexaacetic acid).

Next, Examples will be given to show the details of the present invention more specifically.

The impregnation effect, stability against zinc and copper, and stability against light and temperature were measured by the following methods.

Impregnation effect: Five ring-shaped iron sintered bodies with a specific gravity of 6.2 were impregnated using the immersion/vacuum method, and were immersed in hot water at 90 degrees Celsius for 15 minutes to undergo a hardening airtightness test (pressure 5 to 9/d). Let's do it.

Stability against zinc and copper: 2 d of impregnating agent was placed in a 5 d colorless and transparent glass bottle, zinc and copper rods were immersed, and the gelation period was measured in an atmosphere of 25 degrees G.

Stability against light and temperature: 300 d of impregnating agent was placed in a 300 d colorless and transparent glass bottle, placed in the sun (temperature 23 to 35 degrees Celsius), and the gelation period was measured.

Example Using a mixture of 800 parts of 2-hydroxyethyl methacrylate, which is a type of monomer of methacrylic acid ester, 100 parts of polypropylene glycol dimethacrylate, and 100 parts of glycidyl methacrylate, the following components were added and prepared for l+81 impregnation. obtained the drug.

20 parts of t-7 tilveroxy 2-edylhexylnate (polymerization initiator) 2 parts of hydroquinone monomethyl ether (1 polymerization inhibitor) The metal chelate compound within the range of N.

THPED was added to 1 to 3, HEDPA was added to Nf14 to 6, and for comparison, hydroquinone was added to Nα7, and HEDPA was added to Nf14 to 6.
No. 0 nlubento was added, β-puftholaldehyde was added to 11Q9, and no addition was made to No. 10.

For each, the stability against zinc and copper, the stability against light and temperature, and the impregnation effect were measured. The results are shown in Table-1.

Table-1 Based on the above, the product of the present invention can be applied to metals as well as light and plates. It is an organic impregnating agent that is stable even with respect to temperature.

Claims (1)

[Claims] Impregnating agent for metals consisting of an acrylic ester and/or methacrylic ester monomer, a polymerization initiator, a polymerization inhibitor, and a metal chelate compound as a stabilizer