JPS5871379A - Preventing method for rust - Google Patents

Abstract

PURPOSE:To prevent the formation of rust on a metal in a packaging meaterial coated with a volatile corrosion inhibitor or in a container contg. the inhibitor due to internal dew condensation, the inflow of rain water, etc. and the release of the inhibitor by using a porous material having open pores and causing practically no water permeating phenomenon as at least a part of the packaging material or the lid of the container. CONSTITUTION:A porous material having open pores and causing practically no water permeating phenomenon is used as a part or the whole of a packaging material for a metal coated with a volatile corrosion inhibitor or as a part or the whole of the lid of a container for the metal contg. the inhibitor sealed therein. The porous material is a water repellent nonwoven fabric of synthetic fibers, water repellent sponge or paper provided with water repellency by petroleum resin, aspahlt or the like. Because of the moderate gas permeability of the porous material, internal dew condensation due to a temp. change can be prevented effectively, and since no water permeating phenomenon is caused, the inflow of rain water, etc. can be prevented effectively. The remarkable loss of the volatile corrosion inhibitor is also prevented. The reason is not known.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rust prevention method for effectively sustaining the rust prevention effect on a metal object treated with a rust preventive agent.

BACKGROUND ART Conventionally, a method of using a rust preventive agent has been commonly used to prevent metals from rusting from the viewpoints of economy, workability, and the like.

Unlike rust prevention methods using paint or lining, rust prevention methods using rust preventive agents are often intended for temporary or transitional rust prevention effects, so metal objects that have been treated with rust preventive agents are generally are appropriately packaged and their openings are appropriately sealed before being stored or transported.

Usually, in such cases, the entire metal object is covered with a polyethylene sheet or metal foil polyethylene laminate to protect the metal object treated with a rust preventive agent from rusting factors such as humidity, rainwater, and temperature changes during storage and transportation. Cover the opening of a metal object wrapped with a sheet or sealed with a rust preventive agent using a polyethylene sheet.

A method of sealing with a blind 7 lunge or the like is used.

However, since polyethylene is not breathable, condensation tends to form inside the package or metal objects due to temperature changes.
As a result, rust often develops, and metal foil polyethylene laminate sheets -? The use of blind flanges is not common in mass produced objects due to the high cost.

Although the use of silica gel in combination is effective to some extent, it is not preferable because if it is degraded by ultraviolet rays or rainwater, the water absorbing agent will turn into a water retaining agent and cause rust.

Further, although it is possible to prevent dew condensation by providing ventilation holes in the packaging material, cap, etc., it becomes difficult to prevent the inflow of rainwater and the dissipation of the enclosed rust preventive agent, especially the volatile rust preventive agent.

The present invention was made to improve the above problem, and its gist is that a porous material having continuous ventilation holes that does not substantially cause water permeation is used as a vaporizable rust preventive agent. The rust prevention method is characterized in that the method is used as a packaging material or a part of a packaging material for a metal object, or as a lid or a part of the lid for an opening of a metal object sealed with a volatile rust preventive agent.

The porous material used in the present invention is a material that does not substantially cause water permeability and has continuous ventilation pores with appropriate air permeability and moisture permeability, such as synthetic fiber non-woven fabric that has water repellency in itself. Other examples include petroleum resins, anupart, wax, and treated paper, but water-repellent treated paper is preferred because it is inexpensive and can be easily recycled by incineration or recovery after use.

It is preferable to use water-repellent paper with a density of 0.05 to 5 og/J. Paper with a density of 0.05 g/J or less has low strength and high air permeability, and is especially evaporative. When a rust agent is used, its dissipation also increases. Also, the density is 0
．． 50! /cm3 or more has high strength, but has the disadvantage of poor air permeability.

When paper is used as a material, the paper itself may be treated to be water-repellent as described above, but it may also be a non-woven fabric mixed with various water-repellent synthetic fibers, and if desired, the mixed non-woven fabric may be treated to be water-repellent. good. In addition, when particularly high strength is required, for example when subjecting to severe transportation or cargo handling conditions, reinforcing nets made of resin and/or fiber may be laminated.

The porous material used in the present invention is generally JIs-L
-1092 water repellency is 50-lo.

Points preferably 80-100 points, JIS-P-8117
The air permeability is 400 seconds or less. The thickness of the paper can be freely selected within the above air permeability range.

Such porous rope materials should be molded into an appropriate size and shape depending on the type, size, form, transportation method, case and period of storage, etc. of the metal object to be treated with rust preventive agent. Bye.

For example, in the case of metal objects such as bolts and nuts, the entire metal object coated with a rust preventive agent is packaged or stored using the porous material (sheets, bags 1, and boxes made of O. In the case of a metal object of type 1, such as a steel pipe, a rust preventive agent is sealed inside the pipe, and the above-mentioned porous material is provided at the opening.

In such cases, the packaging material and lid are usually entirely n'+1
However, if desired, only a portion thereof may be made of the porous material.

The porous material used in the uninvented rust prevention method has appropriate breathability, so it effectively prevents internal condensation caused by temperature changes.
Also, since it has water repellency that virtually does not cause water permeation, it effectively prevents the inflow of rainwater, etc., and eliminates the problems of rust and corrosion caused by these causes, and is also effective as a rust preventive agent. Effectively sustained.

What is even more surprising is that metals treated with volatile rust preventives have been thought to have little effect unless they are sealed to prevent the dissipation of vaporized rust inhibitors. It was found that when used, there was no noticeable wear and tear, and the effectiveness of the volatile rust preventive agent was not affected in any way.

Although scientific proof of this phenomenon has not yet been made, the molecular volume of a volatile rust inhibitor is not as small as that of gaseous water molecules or air, so it cannot penetrate as easily as these, and the relationship between vaporization and adsorption properties. It can be inferred that there is a

Hereinafter, the present invention will be explained by examples.

Example 1 Volatile rust preventive agent vp-1 (commercial product from Neos) was sprayed inside a 150A Sch 40 (L = 70α) steel pipe (manufactured by Kawasaki Steel Corporation) at a rate of 5 f/wl, and the opening was Water repellency (J l5-L-10L2) 100 points, air permeability (JIS
-P-8117) Paste 9 with water-repellent paper (thickness = 25 pus, density: 0.108f/α3) made of 2 seconds material,
I left it outdoors in the open air for 6 months, but no rust was observed.

Furthermore, the rust preventive agent remained in a smooth state when it was sealed, and no visible dissipation of the rust preventive agent was observed.

Comparative Example 1 A water-repellent paper similar to that of Example 1 was attached to the opening of a 150A Sch 40 (t=70α) steel pipe at 6 hours outdoors in the open air.
When I ran it for a month, small rust spots were found all over the inside of the tube.

Comparative Example 2 150A Sch 40 (L=70ffi) 51.5% of the lambda-resistant rust preventive agent vr'-1 was applied inside the steel pipe. /Wf, and when the opening was covered with a polyethylene cap and fixed with vinyl tape and left outdoors for 6 months, condensed water collected inside the cap and rust was observed near the opening.

Even the non-rusting parts inside the steel pipes were damp and covered with ivy.

Comparative Example 3 A polyethylene cap was placed over the opening of a 150A Sch 40 (L = 701) steel pipe, fixed with vinyl tape, and left outdoors in the open air for 6 months. As a result, condensed water accumulated inside the cap and covered the entire inside of the steel pipe. Rust was scattered, and corrosion was seen in the opening where water had collected.

Patent applicant: Neohnu Co., Ltd. 42

Claims (1)

[Scope of Claims] 1. A packaging product or a part of a packaging material for a metal object or a part of a packaging material, or a part of a packaging material for a metal object coated with a non-porous composite material having continuous ventilation holes that do not substantially cause water permeation phenomenon, or a volatile rust preventive agent. j! A rust prevention method characterized in that it is used as a lid or a part of a lid for an opening of a metal object sealed with rli. 2. The method according to item 1, wherein the porous substrate is water-repellent paper with a density of 0.05 to 0.50 y/-. 3. Porous cord (water repellency according to JIS-L-1092 in 4. 50 to 100 points, preferably 80 to 100 points, JI
5-P-s 117, the method of combat described in paragraph 1, in which the air permeability is 400 seconds or less.