JP2003117483A - Coating method for coating type steel plate reinforcement material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a deformation of a surface of a steel plate caused by a cure shrinkage of a coating type steel plate reinforcement material. SOLUTION: The coating type steel plate reinforcement material is applied in a constant width by a rotary nozzle controlled by a coating robot in the state that a main agent and a curing agent are mixed and heated to 30-50 deg.C. The coating type reinforcement material in which a center part is thick and an edge part is thin is formed on a surface of the steel plate by coating it such that a coating film is deviated from the first coating position and is superposed thereon and a stepped part of the coated reinforcement material is made small. The coating films are provided in a row and a coating is again carried out on the center part to form the coating film having a thick center part. The center part of the reinforcement material has a thickness required for reinforcing the steel plate. The thickness of the edge of the reinforcement material is formed to thin and the stepped part is made small. Thereby, a deformation of the steel plate caused by a cure shrinkage of the reinforcement material is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating method for coating a coating type reinforcing material on a steel sheet for automobiles and the like.

[0002]

2. Description of the Related Art Reducing the weight of an automobile is an important issue,
Steel sheets used for automobiles have been thinned to the limit of safety and structural requirements. For this reason, in particular, a steel plate reinforcing material called a dent material is attached to the steel plate forming the outer shell of the automobile or heat-sealed to improve the rigidity.

A coating type steel plate containing a two-component curing resin as a main component, which is attached to a place where it is difficult to attach the reinforcing material as a molded product, or is applied to the steel sheet as a lighter reinforcing material to form a reinforcing material. Reinforcement materials have been proposed. This reinforcing material has a problem of high viscosity and poor workability in coating. Further, as shown in the graph of the film thickness of the reinforcing material and the reinforcing performance, the reinforcing material needs to be applied to a certain thickness or more in order to exert the reinforcing function, but since it has high viscosity, it is highly advanced. Required skill. In order to solve this problem, it was considered to apply a uniform coating thickness using a slit nozzle.

[0004]

However, when the coating type reinforcing material 2 is applied with a constant thickness by the slit nozzle, a step 3 is formed at the boundary between the applied and non-applied portions as shown in FIG. When the applied reinforcing material 2 is heat-cured, the reinforcing material 2 and the steel plate 1 have different shrinkage rates during cooling, so that the steel plate 1 is pulled and the surface of the steel plate is wavy, which may cause a defect in the appearance. According to the present invention, the coating-type reinforcing material is applied so as not to have a large step, and the steel sheet is pulled during curing so as to prevent a wavy phenomenon.

[0005]

[Means for Solving the Problems] A coating type steel plate reinforcing material is applied so as to overlap the steel sheet surface by a nozzle that moves while drawing a swirling trajectory so that the step of the coating film becomes small and the steel sheet is contracted by the contraction of the coating film. Prevented distortion. Further, the coating film width was made constant, and the coating film positions were shifted to form overlapping portions so that the coating could be performed efficiently. Furthermore, the swivel trajectory of the coating nozzle and the movement of the coating position are carried out by a coating robot so that the reinforcing material is accurately coated on a predetermined swivel trajectory so that the overlapping amount can be accurately controlled.

[0006] The application of the reinforcing material is not a spray type but an extrusion coating, and is a swirl type which moves while drawing a known swirl orbit disclosed in JP-A-11-179257 and JP-A-11-235544. Use a nozzle. Further, by heating the pipe and the coating nozzle to 30 to 50 ° C. to apply the coating, the viscosity and the viscosity of the reinforcing material are reduced and a uniform and smooth coating surface of the reinforcing material is formed, so that stable quality and reinforcing effect can be obtained. Can be obtained. When the heating temperature is lower than 30 ° C., the viscosity is not sufficiently lowered, and when the heating temperature is higher than 50 ° C., the curing reaction is promoted and the reinforcing material may gel before coating.

The main component of the reinforcing material for steel sheet used is a room temperature curing two-component type coating material such as polyurethane resin or epoxy resin, but the type of resin is not particularly limited. Polyurethane resin is cured by a reaction between an isocyanate and an active hydrogen compound, and as the isocyanate, tolylene diisocyanate (TDI), methylene diphenyl diisocyanate (MDI), isophorone diisocyanate (IPDI), xylene diisocyanate (XDI), water addition For example, MDI (H ₁₂ MDI). The epoxy resin is bisphenol A type, bisphenol F type, urethane-modified epoxy resin, or the like.

As the curing agent, polyamines, polyamides, polyols and the like can be used, and examples of amines include aliphatic amines, aromatic amines, acid anhydrides, urea resins, melamine resins and phenol resins. Aliphatic amines include diethylenetriamine (DTA), triethylenetetramine (TETA) and the like, and adducts having an amino group at their ends, and aromatic amines include metaphenylenediamine (MPD) and diaminodiphenylmethane (DDM). , Diaminodiphenyl sulfone (DDS) can be used.

In order to improve the coating workability of the coating type steel plate reinforcing material, it is necessary to reduce the viscosity of the epoxy resin coating material, and for this purpose, it is desirable to add an epoxy reactive diluent. Various diluents are known, and the diluent is not limited to a specific diluent.

Fillers, which are well known as additives for paints, are added as necessary. Fillers include various extender pigments and coloring pigments such as calcium carbonate, barium sulfate, talc, clay, kaolin, zinc white, titanium oxide, silica, alumina, plastic balloons, glass balloons, ceramic balloons, silica balloons, shirasu. Lightweight and low specific gravity fillers such as balloons can be used. Other additives include a dehydrating agent, a hygroscopic agent, an anti-sagging agent, a thixotropic additive, a dispersant, an ultraviolet absorber, a high boiling point solvent for improving coating workability, a plasticizer, and an oil surface adhesion effect increasing effect. Powder rubber, acrylic resin for increasing the steel plate reinforcing effect, etc. are added as necessary. The addition amount of these additives is appropriately 0 to 10% by mass.

The coating type steel plate reinforcing material is manufactured by using a conventionally known disperser for paints, and a disperser such as a dissolver, a planetary mixer, an open kneader, a vacuum kneader, a roll mill, a ball mill or a Glen mill can be used. . As a method of mixing the main component and the curing agent of the quick-curing coating material, there is a method of mixing the two in an equivalence ratio in advance, and feeding the mixture by pressure to apply it by a coating machine. In this case, the coating operation is continuously performed. If there is a line stop for lunch break or some other reason,
There is a risk that the curing reaction will proceed in the pipe and block the pipe. The main agent and the curing agent are pressure-fed by separate pipes,
Immediately before the coating machine, collision type mixer (static mixer)
There is a method in which a known two-component mixer such as the above is arranged and the reinforcing material mixed at the reaction equivalent ratio is applied. In this case, it is only necessary to wash only the portion ahead of the mixer, and it is possible to prevent embolism in the piping and the coating machine.

As for the coating pattern, as shown in the schematic view of FIG. 1 and the embodiment of FIG. 2, the swirl width and moving speed of the swirl type nozzle are appropriately determined so that a coating film having a predetermined film thickness can be obtained. The nozzle is swiveled to apply a uniform width. The next coating film is applied side by side to the formed coating film, and is applied again to the central portion of the formed coating film by the swirling nozzle. The cross-sectional shape of the coating film is as shown in FIG. The step 3 is gentle. A thicker coating film in the central portion of the upper layer is more effective in relaxing the occurrence of strain than the coating film thickness in the lower layer.

As other coating patterns, as shown in FIG. 4, (1) the swirling nozzles are arranged so that the coating positions are shifted and overlapped so that the central portion becomes thicker and the edge portion becomes thinner. ) Although it is applied so that it overlaps, the moving speed of the swirling nozzle is increased so that circular coating films are not overlapped in a strip shape,
A spiral shape, or (3) increasing the first application width and applying a narrower application width on top of it.
The reinforcing material can be applied to the steel sheet in various patterns. Such change of the coating pattern can be freely set by the coating robot.

[0014]

Example 1 100 parts by mass of a bisphenol F type epoxy resin having an epoxy equivalent of about 300, 50 parts by mass of an epoxy reactive diluent having an epoxy equivalent of about 250 as a main agent, and an amine adduct of diethylenetriamine (DTA) as a curing agent. 50 parts by mass of curing agent, calcium carbonate 300
30 parts by mass of the additive and 30 parts by mass of the additive are mixed and dispersed by a planetary mixer, the main agent and the curing agent are pressure-fed by an airless pump, and the main agent and the curing agent are mixed at a reaction equivalence ratio by a mixer arranged immediately before the nozzle, and piping and With a swirl type nozzle that heats the nozzle to about 50 ° C, a coating film thickness of 0.5 mm is applied to a 0.8 mm thick steel sheet for automobiles on which rust preventive oil is attached
Apply with a swirl width of 40 mm, 2 with the same coating thickness and swirl width
The first with a total width of 60 mm, which is applied so that it has an overlap of 0 mm and has an overlap of 20 mm in the center.
A layer coating film was obtained. The coating thickness of 1.
It was applied with a swirl width of 0 mm and a width of 40 mm, the second layer coating was applied on both sides of the first layer coating 10 mm, and the central portion was formed thick, and the required rigidity was obtained and the corrugated surface of the steel plate was obtained. No such deformation was observed.

[0015]

Example 2 As in Example 1, 100 parts by mass of a bisphenol F type epoxy resin having an epoxy equivalent of about 300 as a main component, 50 parts by mass of an epoxy reactive diluent having an epoxy equivalent of about 250, and diethylenetriamine (D
50 parts by mass of a curing agent by an amine adduct of (TA), 300 parts by mass of calcium carbonate, and 30 parts by mass of an additive are mixed by a planetary mixer, and the main component, the curing agent and the additive are pressure-fed by an airless pump, and they are arranged immediately before the nozzle. The main component and the curing agent were mixed in a reaction equivalence ratio by the mixing machine, and the film thickness was applied to the 0.8 mm thick steel plate for automobiles on which the rust preventive oil was adhered by the swivel nozzle in which the pipe and the nozzle were heated to about 50 ° C. A first layer with a total width of 70 mm, which is applied with a swirl width of 0.5 mm and 50 mm, and adjacently applied so as to have an overlapping portion of 30 mm with the same coating film thickness and swirling width, and having an overlapping portion of 30 mm in the central portion. A coating film was obtained. Apply to the center of the inside of this coating film with a coating thickness of 1.0 mm with a swirl width of 50 mm,
Apply the second layer coating on both sides 10 mm inside the first layer coating,
When the central portion was formed thick, the required rigidity was obtained, and no deformation such as corrugation of the steel plate surface was observed.

[0016]

According to the method for applying a reinforcing material for steel sheet of the present invention, the edge portion of the reinforcing material after application is formed thinner than the central portion, and the force of pulling the steel sheet during curing shrinkage is weak. There is no distortion and the wave phenomenon on the steel plate surface is prevented. Since the swivel nozzle is controlled by the coating robot, it is possible to accurately control the coating width, the overlapping amount of coating films, and the like.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a coating pattern by a swirl nozzle.

FIG. 2 is an example of a coating pattern using a swirl nozzle.

FIG. 3 is a sectional view of a reinforcing material applied by the method of the present invention.

FIG. 4 is an explanatory diagram of another coating pattern.

FIG. 5 is a cross-sectional view of a conventional coating-type reinforcing material.

FIG. 6 is a graph showing the relationship between the film thickness of the reinforcing material and the reinforcing property.

[Explanation of symbols]

1 steel plate 2 Reinforcement material 3 steps

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masamitsu Kawazoe             4-16 Isoyama, Suzuka City, Mie Prefecture (72) Inventor Yoshiaki Watanabe             8-16-15 Toyoshima, Kita-ku, Tokyo Japan Special             Paint Co., Ltd. Development Center (72) Inventor Akio Sato             8-16-15 Toyoshima, Kita-ku, Tokyo Japan Special             Paint Co., Ltd. Development Center (72) Inventor Hirofumi Kondo             8-16-15 Toyoshima, Kita-ku, Tokyo Japan Special             Paint Co., Ltd. Development Center F term (reference) 3D003 AA01 BB01 CA05 CA36 CA42                       CA45                 4D075 AA37 AA38 AC08 AC88 AE04                       AE05 CA12 DA06 DB02 DC11                       EA27 EA31 EA35 EB32 EB33                       EB34 EB37 EB38 EB39 EB45

Claims (4)

[Claims] 1. A coating type steel plate reinforcing material, which is applied a plurality of times so as to overlap a steel sheet surface by a nozzle that moves while drawing a swirling trajectory to form a strip-shaped coating film with a thick center and thin edges. How to apply. 2. The method for applying a coating type steel plate reinforcing material according to claim 1, wherein the coating film width is constant and the coating film positions are shifted to form overlapping portions. 3. The method for applying a coating type steel plate reinforcing material according to claim 1, wherein coating films having a constant width are provided side by side and the coating film is formed thereon. 4. The coating method of a coating type steel plate reinforcing material according to claim 1, wherein the orbit of the coating nozzle and the movement of the coating position are performed by a coating robot which is program controlled.