JP2549326B2 - Roof coating composition - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating composition for a roof, which can be applied in a thick film and has excellent corrosion resistance.

[0002]

2. Description of the Related Art When a metal plate such as a galvanized iron plate and an iron plate is used in a roofing material for general houses, warehouses, livestock houses, etc., various coating materials are usually coated for the purpose of imparting corrosion resistance and aesthetic appearance. ing. Oil-based paints, synthetic resin-based paints and bituminous-based paints have been widely used as such coating materials.

[0003]

However, among the conventional coating materials, for example, the oil-based coating material has a problem that when it is applied to a galvanized sheet, it forms a metal salt, is easily peeled off, and has poor weather resistance. Synthetic resin-based paints have excellent weather resistance and corrosion resistance, but it is difficult to form a thick film and therefore have limited durability; and bituminous paints such as asphalt and coal tar are Although it is excellent in corrosion resistance and can be formed into a thick film, it suffers from problems such as softening and sagging of the coating film in high humidity such as summer, and poor aesthetics because it is only black.

In view of the above situation, the present inventors have developed a roof coating material capable of thick film coating, excellent in weather resistance and corrosion resistance, and capable of directly coating an old coating film. As a result of intensive investigations to achieve the present invention, the present invention has been achieved.

[0005]

Means for Solving the Problems That is, the present invention comprises (A) 100 parts by weight of a petroleum resin having a number average molecular weight of 2000 or less, (B) 20 to 100 parts by weight of a thermoplastic polystyrene-based elastomer, and (C) a plasticizer 20 to The present invention relates to a roof coating composition containing a coating film forming component consisting of 150 parts by weight, (D) 50 to 300 parts by weight of scale-like aluminum pigment, and (E) 10 to 300 parts by weight of fibrous material.

Hereinafter, the present invention will be described in detail. The petroleum resin (A) which is a constituent of the coating composition of the present invention is an aliphatic petroleum resin in which a conjugated diene of C ₅ fraction such as cyclopentadiene and 1,3-pentadiene is partially cyclopolymerized; petroleum naphtha Aromatic petroleum resin obtained by polymerizing C ₉ fraction such as styrene derivative and indene from heavy oil by-produced by decomposition;
Copolymerized petroleum resin obtained by copolymerizing ₅ fractions and C ₉ fraction; number average molecular weight 2 such as hydrogenated aromatic petroleum resin and alicyclic petroleum resin obtained by polymerizing dicyclopentadiene
It is a polymer of 000 or less.

The petroleum resin is added in order to enable thick film coating and impart corrosion resistance, but the number average molecular weight is preferably within the above range, particularly preferably in the range of about 500 to 2000, and more than 2000. If so, it becomes difficult to dissolve in a solvent and the coating workability deteriorates, which is not preferable. Examples of the polystyrene-based thermoplastic elastomer (B) which is a constituent of the coating composition of the present invention include styrene-butadiene-styrene block polymer (SBS) and styrene-
A typical example is isoprene-styrene block polymer (SIS).
~ 50% by weight, viscosity is 25% by weight in toluene solution 30
The one of 0 to 3000 CPS (25 ° C.) [B-type viscometer] is suitable.

The polystyrene-based thermoplastic elastomer is
It is added in order to impart flexibility, adhesion, durability, etc. to the obtained coating film, and the amount thereof is preferably 20 to 100 parts by weight with respect to 100 parts by weight of the petroleum resin (A). is there. As the plasticizer (C) which is a constituent component of the coating composition of the present invention, process oil is desirable, but other dibutyl phthalate, dioctyl phthalate, diethyl phthalate, tricresyl phosphate, trioctyl phosphate, diethyl adipate, etc. Various known plasticizers can be used. The plasticizer is added in order to improve the compatibility of each component and to impart flexibility, cold resistance and the like to the resulting coating film, and the amount thereof is 100 parts by weight of the petroleum resin (A). On the other hand, 20 to 150 parts by weight is suitable.

The flaky aluminum pigment (D) which is a constituent of the coating composition of the present invention has an average particle size of about 5 to 3
The thickness of 0 μm is applicable, and either a leafing type or a non-leafing type is preferable, and a paste type is preferable. That is, it is a mixture of flake-shaped aluminum powder, a medium such as mineral spirit, solvent naphtha, a solvent such as toluene and xylene, a lubricant such as stearic acid and a fatty acid such as oleic acid, a dispersant, and an anticorrosive agent.

The flake-shaped aluminum pigment not only colors the coating film but also blocks the sunlight to impart weather resistance, and prevents corrosion factors such as water from entering the coating film.
It is added in order to impart corrosion resistance, and the amount is 50 to 100 parts by weight of the petroleum resin (A).
300 parts by weight is suitable. Examples of the fibrous material (E) which is a constituent component of the coating composition of the present invention include inorganic fibrous materials such as potassium titanate, asbestos, rock wool and glass fiber; pulp, cellulose and synthetic resin. Typical examples include organic fibrous substances such as a system. The fibrous material has an average length of 2 mm or less and a diameter of 0.1 to 30 μm.
Those of about m are suitable. The fibrous material is added to prevent sagging when the film is thickened, and to prevent cracking of the resulting coating film, and the amount thereof is 100 parts by weight of the petroleum resin (A). 10 to 300 parts by weight is suitable.

The coating composition of the present invention contains the above-mentioned coating film forming components as essential components, and if necessary, various extender pigments, anticorrosive pigments, coloring pigments, modified resins or dispersants, thickeners, surface modifiers. Additives such as agents, antioxidants, ultraviolet absorbers and coupling agents are blended. The coating composition of the present invention, in these coating film forming components, an organic solvent, for example, a usual coating solvent such as xylene, toluene, cyclohexane, diethyl ether, butyl acetate, butyl cellosolve, and mineral spirit, the solid content of the coating composition. Is about 4
It is composed of a mixture of 0 to 90% by weight.

The coating composition according to the invention can be applied not only to new metal roofs, but also to roofs with old coatings. However, for a roof with an old paint film, if the old paint film has chalking, blistering, etc., it is desirable to adjust the surface of the old paint before applying. As a coating method, ordinary coating means such as spray coating, roller coating, and brush coating can be used, but in the case of thick film coating, airless spray coating is particularly preferable. The coating film thickness is not particularly limited, but is usually 100 to 1
It is suitable to have a thickness of about 000 μm.

[0013]

The roof coating composition of the present invention has corrosion resistance,
It has excellent weather resistance, bending resistance, etc., and since it can be applied to thick film coating without sagging, it has excellent durability.
Furthermore, since it has good penetrability and adaptability to the old paint film, it has the feature that it can be applied on the old paint film.

[0014]

EXAMPLES The present invention will now be described in more detail with reference to examples. In addition, "part" and "%" are shown on a weight basis. In the following Examples 1 to 3 and Comparative Examples 1 to 4, the compounding ingredients were sufficiently mixed and dissolved to prepare roof coating compositions. Example 1 Petroleum resin Note 1) 100 parts Thermoplastic elastomer Note 2) 40 parts Naphthene-based process oil 70 parts Aluminum paste Note 3) (Solid content equivalent) 80 parts Fibrous material Note 4) 80 parts Toluene 300 parts Note 1) "Petrogin 120" (trade name, manufactured by Mitsui Petrochemical Co., Ltd.), number average molecular weight 1200 Note 2) Styrene / isoprene / styrene block polymer; styrene content 15%, 25% toluene solution viscosity 14
00CPS (25 ° C) * 3) "Alpaste # 2" (trade name, manufactured by Asahi Kasei Co., Ltd.), solid content 67% * 4) Rock wool (average length 100μm, diameter 5μ
m) Example 2 Petroleum resin Note 1) 100 parts Thermoplastic elastomer Note 2) 80 parts Naphthene-based process oil 40 parts Aluminum paste Note 3) (as solid content) 120 parts Fibrous material Note 4) 50 parts Toluene 300 parts Comparison Example 1 Petroleum resin Note 1) 120 parts Naphthene-based process oil 80 parts Aluminum paste Note 3) (as solid content) 90 parts Fibrous material Note 4) 80 parts Toluene 300 parts Comparative Example 2 Petroleum resin Note 1) 120 parts Thermoplastic Elastomer Note 2) 60 parts Aluminum paste Note 3) (Solid content equivalent) 100 parts Fiber material Note 4) 90 parts Toluene 300 parts Comparative Example 3 Petroleum resin Note 1) 120 parts Thermoplastic elastomer Note 2) 60 parts Naphthene-based process Oil 90 parts Aluminum paste Note 3) (as solid content) 100 parts Toluene 300 parts Comparative Example 4 Petroleum resin Note 1) 100 parts Thermoplastic Rustomer Note 2) 80 parts Naphthenic process oil 80 parts Fibrous substance Note 4) 60 parts Toluene 250 parts Example 3 Petroleum resin Note 5) 100 parts Thermoplastic elastomer Note 6) 50 parts Paraffinic process oil 70 parts Aluminum paste Note 7) (Solid content equivalent) 100 parts Fibrous substance Note 8) 100 parts Toluene 320 parts Note 5) "Quinton 1525L" (product name of Nippon Zeon Co., Ltd.), number average molecular weight 1500 Note 6) Styrene / butadiene / styrene block polymer Styrene content 20%, 25% toluene solution viscosity 18
00CPS (25 ℃) Note 7) "Sap110" (trade name of Showa Aluminum Powder Co., Ltd.,
66% solids Note 8) Calcium sulfate whiskers (average length 60 μm,
Diameter 2 μm) Reference Example 1 A mild steel sheet was coated with a coating composition of Examples 1 to 3, a coating composition of Comparative Examples 1 to 4 and a commercially available oil-based paint as Comparative Example 5 so that a dry film thickness was 200 μm. Then, the coated plate was prepared by leaving it at room temperature for 2 days. Reference Example 2 An iron plate coated with an alkyd resin coating so that the dry film thickness was 50 μm was exposed outdoors for one year. After removing dusts and other deposits on the coated plate with a thinner, each coating material was applied again in the same manner as in Reference Example 1 to prepare a coated plate.

The coated plates of Reference Examples 1 and 2 were tested for weather resistance, corrosion resistance and bending resistance, and the results are shown in Table 1. (Weather resistance test) After outdoor exposure, visually check the state of the coating film ◎: No abnormality, ○: Slight abnormality such as blistering, chalking, cracks △: Abnormal occurrence of blistering, chalking, cracking, etc. ×: Coating Film peeling (corrosion resistance) Cross-cut on the coated surface, salt spray test 7
After 00 hours, the state of the coating film is visually judged. ◎: No abnormality, ○: Rust flow is present △: Blistering, some rusting is present, ×: Blistering, rusting is significantly present (bending resistance) Bending the coated plate 90 °, Visual observation of the coating film state at the bent part ◎: No abnormality, ○: Slight cracks occurred △: Large cracks occurred, ×: Film peeling Table 1 ─────────────── ─────────────── Reference example 1 Reference example 2 Weather resistance Weather resistance Flex resistance Flex resistance 1 year after 3 years Corrosion resistance Flexibility 1 year after 3 years Corrosion resistance Flexibility implementation Example 1 ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ 〃 2 ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ 〃 3 ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ Comparative Example 1 ○ ○ ○ × ○ △ △ × 〃 2 ○ ○ ○ △ ○ △ △ × 〃 3 ○ ○ △ × ○ △ × × 〃 4 △ × △ ○ △ × △ ○ 〃 5 ○ △ × × ○ × × × As is clear from Table 1, the coating composition of the present invention is excellent. It had good coating performance. On the other hand, Comparative Example 1 containing no thermoplastic elastomer, Comparative Example 2 containing no plasticizer, and Comparative Example 3 containing no fibrous material had particularly poor flex resistance. In addition, Comparative Example 4 containing no flake-shaped aluminum pigment had particularly poor weather resistance. In addition, Comparative Example 5 using the conventional oil-based paint had poor corrosion resistance, bending resistance, and the like.

Claims (1)

(57) [Claims] 1. (A) 100 parts by weight of a petroleum resin having a number average molecular weight of 2000 or less, (B) 20-100 parts by weight of a thermoplastic polystyrene elastomer, (C) 20-150 parts by weight of a plasticizer, (D) flaky. A roof coating composition containing a coating film forming component consisting of 50 to 300 parts by weight of an aluminum pigment and 10 to 300 parts by weight of (E) a fibrous material.