JPS6149839A - Reinforcing material for thin steel plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a reinforcing material for thin steel plates, and more specifically, to a reinforcing material for reinforcing thin steel plates such as automobile doors and rear fenders. Regarding materials.

[Conventional technology]

For metal outer panels (thin steel plates, etc.) such as automobile doors,
When driving on rough roads, there is a risk that stress will concentrate at certain points on the outer skin, leading to out-of-plane deformation of the outer skin, and to prevent this, reinforcing materials have traditionally been attached to these locations. There is.

An epoxy prepreg type material is known as one of such reinforcing materials. This is constructed by laminating a thermosetting adhesive layer made of a mixture of an epoxy resin, a hardening agent, and a filler on one side of a reinforcing layer (glass cloth).

In addition, an epoxy foam type is known, and this is used to reduce the thickness of the reinforcing material of the previous R1 and epoxy prepreg type to improve economic efficiency and weight reduction, as well as improve the fixation to the plate material. , an unfoamed foam material is attached to one side of the metal plate, leaving only a surface to be adhered to the metal plate. (
(For example, Japanese Patent Application Laid-open No. 57-151348) [Problems to be solved by the invention] However, the conventional epoxy prepreg type has poor oil fixing properties (particularly tackiness at low temperatures f).
J'- had the disadvantage of being significantly inferior.

Furthermore, even if the epoxy foam type is used, it still has poor oil surface fixing properties (h') and therefore can only be applied to coated plates.

Furthermore, both of the conventional reinforcing methods described above have the disadvantage that storage stability is poor (and the adhesive layer easily deteriorates when stored at high temperatures for a long period of time).

An object of the present invention is to provide a new 4HrsM material that eliminates the drawbacks of the conventional reinforcing materials.

[Means for solving problems]

In order to achieve the above object, the present invention provides a reinforcing material for a thin steel plate comprising a thermosetting adhesive layer and a metal reinforcing layer serving as a reinforcing material supporting one side of the thermosetting adhesive layer. When forming the adhesive layer into a sheet shape, the added mixed component is mainly 10 to 40% by weight of SBR.

10-40% by weight of acrylic polyfunctional monomer, 30-40% by weight
A reinforcement is provided consisting of 60% by weight inorganic filler and the required amount of peroxide as a polymerization agent for the acrylic polyfunctional monomer.

That is, the reinforcing material of the present invention is characterized by specifying the mixed components and their proportions that constitute the thermosetting adhesive layer.
As a result, a reinforcing material was obtained that has excellent oil surface fixation and storage stability that could not be achieved with conventional force reinforcing materials, as well as high mechanical strength.

Among the mixed components of the thermosetting adhesive layer, 5DR (styrene/endetadiene rubber) contributes to improving the bondability of the mixture of the acrylic polyfunctional monomer and the inorganic filler to the oil surface. The mixing ratio of SBH is preferably 10 to 40% by weight, particularly preferably 15 to 23% by weight. S
If the BH mixing ratio is 10% heavy elongation, the oil surface fixing property at low levels will be poor, and if it exceeds 40% heavy elongation, the reinforcing property (
bending strength) decreases.

The acrylic polyfunctional monomer is not particularly limited as long as it provides reinforcing properties to the adhesive layer (e.g., ethylene glycol dimethacrylate, 1,6 hegysanglycol dimethacrylate, ethoxylated (Et
Diesters such as bisphenol A dimethacrylate, triesters such as trimethylolpropane trimethacrylate, and tetraesters such as tetramethylolmethanetetraacrylate may be used.

The mixing ratio is preferably 10 to 40% by weight, especially 15% by weight.
~20 Z batting % is preferred. If this mixing ratio is less than 10% by weight, the reinforcing properties will be reduced, and if it exceeds 40% by weight, the rigidity will become too high, and the thin steel plate will be distorted due to shrinkage of the adhesive layer during curing.

Among the acrylic monomers, the reason why we selected multifunctional ones is that when using monofunctional ones, the specific odor can be reduced by P2.
Therefore, this was avoided.

The inorganic filler is used to improve the reinforcing properties of the adhesive layer, prevent sagging, increase the strength, etc., and its type is not particularly limited, and calcium carbonate, silica, etc. are usually used.

The mixing ratio is 30~6o weight! %, particularly preferably 30 to 45% by weight.

When this mixing ratio is less than 30% by weight, the viscosity decreases significantly and it becomes difficult to maintain the shape of the sheet-like molded layer, while when it exceeds 60% by weight, the viscosity increases significantly and the oil surface fixing property decreases.

Peroxide r is added in a necessary amount as a polymerization agent for the acrylic polyfunctional monomer, and is usually added in an amount of 0.1 to 5 parts by weight per 100 parts of the acrylic polyfunctional monomer. Peroxy V preferred in the present invention has a decomposition temperature of 80 to 13
For example, a dialkyl peroxide such as 1#1-di(t-butylperoxy)3.3.5-trimethylcyclohexane or a ketone peroxide such as methyl isobutyl ketone peroxide is used at 0°C. Ru.

In addition, the metal reinforcing layer, which is a support that supports one side of the thermosetting adhesive layer, is not particularly limited as long as it has good shape followability, high rigidity, and conductivity, but generally aluminum, iron, or galvanized material is used. Steel plates, tin-plated copper plates, etc. are used.

In order to improve adhesion, the reinforcing material for thin steel sheets of the present invention has a thermosetting adhesive layer of 2 to 8% by weight when forming into a sheet shape.
It is desirable to further add 2 to 20% by weight of a synthetic resin such as a hydrogenated ester resin or a natural resin having an adhesion-imparting effect to the epoxy resin.

If the epoxy resin content is less than % double needle, the adhesion will be poor;
If it exceeds the weight percentage, it will easily flow and retain its shape before heat curing. - There are some difficulties, and it becomes too hard after thermosetting (it causes distortion in the reinforcing material, which is not preferable).

If the amount of synthetic resin or natural resin is less than 2% by weight, the adhesion will be poor like that of epoxy resin, and if it exceeds 20% by weight, the resin will melt during thermosetting, causing sagging and shifting, which is not preferable.

Furthermore, the metal reinforcing layer of the thin steel plate reinforcing material in the present invention is
It is preferable to add 5 to 15% by volume of general-purpose metal fibers such as aluminum, copper, nickel, iron, etc. to the adhesive layer so that the electrodeposition paint for rust prevention can be attached.

If the metal fiber content is less than 5% by volume, no conductive effect will be obtained and the electrodeposition paint will not adhere to the metal reinforcing layer, resulting in 1 volume M1
If it exceeds %, the amount of metal fibers h'' will be too high, resulting in poor oil surface fixing properties and causing distortion in the reinforcing material, which is undesirable.

The reinforcing material for thin steel plates according to the present invention will be explained based on the drawings.

That is, the reinforcing material for thin copper plates of the present invention is mainly made by adding and mixing SBR, an acrylic polyfunctional monomer, an inorganic filler, and a required amount of peroxy-P as a polymerization agent for the acrylic polyfunctional monomer, and forming the mixture into a sheet. Thermosetting adhesive layer 1
is constructed by laminating one side thereof as a surface 2 to be adhered to the steel plate, and laminating a metal reinforcing layer 3 serving as a reinforcing material supporting the adhesive layer 1 on the other side.

Next, a method for manufacturing a reinforcing material for thin steel plates according to the present invention will be explained.

SDR and acrylic polyfunctional monomers are put into a kneader (mixer) used for operation, stirred and mixed thoroughly, and then inorganic fillers and peroxides are added (if necessary, epoxy resins, synthetic resins, Natural resins, metal fibers, etc. are also added.) Further kneading is performed. Next, the kneaded product is formed into a sheet to form a thermosetting adhesive layer, and a metal reinforcing layer is laminated on one side, thereby completing the reinforcing material h'' of the present invention.

The other side of the contact M layer will be the surface to be attached to the thin steel plate,
This surface is covered with a release paper to prevent contamination due to dust, etc., and to prevent deterioration of adhesion.

[Function 1] The reinforcing material for thin steel plates of the present invention is attached to the stress concentration area of a metal outer plate (thin steel plate) such as the rear fender of a car, etc., and then, for example, about 180 'O in 2
By heating and curing for 0 to 60 minutes, it can be attached with good fixing and adhesion properties even to thin steel plates whose surfaces are oily, and is effective in preventing out-of-plane deformation of the thin copper plates when driving on rough roads. prevent it from happening.

〔Effect of the invention〕

Since the reinforcing material for thin steel plates of the present invention has the above-described structure and function, it not only has high mechanical strength such as bending strength, shear strength, and impact resistance after heat hardening, but also has high oil surface fixability and It has excellent adhesion to oil surfaces, and has very good storage stability, and the adhesive layer does not easily gel even if stored at high temperatures for a long period of time.

Further, if the reinforcing material is applied to a thin steel plate in a normal flow, then electrocoated and then heated, the curing process of the reinforcing material and the electrocoated coating can be performed at the same time, which is economical.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

As a reinforcing material, unless otherwise specified, the reinforcing layer is 0.
．． A sample was prepared by laminating 2 mm thick galvanized steel plates with a 1 mm thick adhesive layer. Thin steel plate is 0.
8+nm thickness [Nippon Steel Corporation cold rolled steel plate 5PO
After adhering the reinforcing material to the thin steel plate, the heating curing conditions were 180'c x 20 minutes.

〔Test method〕

■Oil surface fixability After attaching the sample at room temperature to an oil surface thin steel plate that has been drained of oil for 2Δ hours and leaving it for 1.1 minutes, it was fixed to a thin oil surface (1N!). ! Measure the deviation of the test guide when the board is placed vertically. There is no pre can,
The ladle had no cracks, but the sample was partially floating due to the thin copper plate.

■Slamming Test Measure surface 4 impact resistance based on J Engineering 5K6830Ha 26.6 (2).

■Strain test of thin copper plate: Paste the material on a thin bent plate, and measure the strain of one thin forceps plate after heating and curing using a three-dimensional measurement rock. Less than 0.1 dragon is nothing, 0
．． A value of 1 vm or more was considered to be present.

■Reinforcement property (bending strength): 5 mm/mi after pasting the sample on a thin copper plate and heating and curing.
The load at the time of one step of deformation when deformed by n was taken as the bending strength. 6kQ/25 fights (1 taste) or more high, 4 to 9/25*
A width of less than 6 kq/25 mm (width) was defined as medium, and a width of less than 4 kq/25 mm (mA) was defined as low.

■Difference during curing A sample is attached to a thin plate, and after curing by heating, the deviation of the sample is measured when the thin copper plate is held vertically. If there was no deviation, it was judged as “no”, and if there was a deviation h″-, it was judged as “present”.

■Shear strength Measured on a heat-cured adhesive layer with a thickness of 1.5 mm in accordance with J-Tech 5x6850.

■ Possibility of electrodeposition coating?Immerse the reinforcing material in a cationic electrodeposition coating solution at room temperature,
After energizing for 0VI minutes, it was visually confirmed whether or not the reinforcing layer was coated with electrodeposition coating/I''.If it was coated, it was judged as acceptable, and if it was not coated, it was judged as unacceptable.

[Examples 1 to 4, Comparative Examples 1 to 8] After mixing the SDR and the acrylic polyfunctional monomer using a kneader (Niegu manufactured by Irie Seisakusho, PNV-1 type), peroxide and an inorganic filler were further added, Kneaded. The mixing ratio is shown in Table 1. This kneaded product was formed into a sheet, a reinforcing layer was laminated on one side of the sheet, and its mechanical strength, properties, etc. were measured according to the test method described above. The results are shown in Table 2.

0LrI 0 Hit 1'O.

Hanging 0 sun ! -t, 11 skewers - o.

U) Comparative Example 1 is a conventional epoxy silipreg type reinforcing material, in which a glass cloth (reinforcing layer) is coated with an adhesive layer (thickness 1.5 mm) consisting of an epoxy resin, a hardening agent, a filler, and a filler. Comparative Example 2 is a conventional epoxy foam type, in which a glass cloth is laminated with an adhesive layer (0.5 mm thick) consisting of a 2+ resin, a hardening agent, a filler, and In addition, a foamed material (5 to 7 m thick) was attached to a thin steel plate, leaving the adhesive surface intact.

[Examples 5 to 7] Regarding the reinforcing materials of the present invention, the shear strength (kg/cIrL2) of the cured adhesive layer was measured. The addition mixing ratio (wt%) and results are shown in Table 6 below.

In addition, AFloo is the interface failure rate of 100%, 0F30.
AF70 means a cohesive failure rate of 30% and an interfacial failure rate of 70%.

No. 6 1,6 Hexane Recall; 20 Dimethacrylate i 1.0 0.9 49 48.6 0.5 [Examples 8-9, Comparative Examples 9-10] Mixing ratio used in Example 7 above Table 4 shows the oil surface fixability, distortion of thin steel sheets, and whether or not electrodeposition coating is possible when samples were prepared by changing the amount of aluminum fiber mixed in composition A. % is expressed as a volume ratio.

4th table work casting
A row [Example 10] Acrylic polyfunctional monomer was converted into ethoxylatera t' (
Kthoxyla, ted, ) bispheno-/l/A
Joki Example 1~ except for changing to dimethacrylate
The same test was conducted under the same conditions as in Example 7. As a result, the same result h1 as in Examples 1 to 7 was not obtained.

[Brief explanation of drawings]

The drawing is a sectional view of the reinforcing material for thin steel plates of the present invention. 1...Touching M layer 2...Steel plate adhesion surface 3...Reinforcement layer Akira Asamura

Claims (3)

[Claims] (1) In a reinforcing material for thin steel sheets consisting of a thermosetting adhesive layer and a metal reinforcing layer serving as a reinforcing material supporting one side of the reinforcing material, the thermosetting adhesive layer is mainly made of SBR, acrylic polyfunctional A sheet-like molded layer formed by adding and mixing a required amount of peroxide as a polymerization agent for an acrylic polyfunctional monomer to the three components of a monomer and an inorganic filler, and the mixing ratio of the three components is SBR 10 to 40% by weight, A reinforcing material for a thin steel sheet, characterized in that it contains 10 to 40% by weight of an acrylic polyfunctional monomer and 30 to 60% by weight of an inorganic filler. (2) When forming the thermosetting adhesive layer into a sheet shape, 2
The reinforcing material according to claim 1, characterized in that up to 8% by weight of an epoxy resin and 2 to 20% by weight of a synthetic resin or a natural resin are added and mixed. (3) When forming the thermosetting adhesive layer into a sheet shape, 5
The reinforcing material according to claim 1 or claim 2, characterized in that metal fibers are added in an amount of 15% by volume.