JPS5922671B2 - Weather resistant laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laminate with improved weather resistance, and more specifically, a laminate made of polyvinyl chloride sheets laminated on a base material, and a large number of plasticizers added to the surface of the sheet. By forming a thin film-like protective layer made of vinyl chloride plastisol or organosol, weather resistance can be significantly increased without sacrificing the excellent secondary workability (bending workability) required for laminates and properties such as cold resistance. This invention relates to a laminate plate that has been improved.

Conventionally, base materials such as metal plates, wood, plastic plates, and glass plates used as building materials have often been coated with polyvinyl chloride sheets for purposes such as rust prevention, pollution prevention, or decoration. The above polyvinyl chloride sheet is usually colored or printed, and a protective film made of a transparent polyvinyl chloride resin film is further laminated for the purpose of preventing damage to the colored or printed surface and enhancing the decorative effect (
(commonly known as an overcoat) is generally known.

However, when the above-mentioned overcoated laminate is used outdoors, compared to the non-overcoated laminate,
The overcoated laminates are hardly used outdoors because the laminate sheets are severely blackened and lose their original decorative effect.

The cause of the above defects is volatile substances generated from various additives contained in the polyvinyl chloride film coated on the base material, or a relatively thick protective film containing decomposition products of polyvinyl chloride resin and additives. It is thought that the sheet and the protective film are sealed in and prevented from escaping to the outside, so heat, light, or the interaction between the two accelerates the deterioration of the sheet and protective film, resulting in decomposition and coloring.

Therefore, the inventors of the present invention have conducted various studies in order to obtain a material with excellent weather resistance and other properties required for a laminate even if a protective film is formed on the sheet, and as a result of various studies, the present invention has been developed. The gist of this is that on a laminate board in which polyvinyl chloride sheets are laminated as a base material, 100% of vinyl chloride resin is
The present invention relates to a weather resistance-improved laminate comprising a protective coating film having a thickness of 5 to 30 microns made of plastisol or organosol containing 20 to 80 parts by weight of plasticizer per 0 part by weight. As described above, the present invention is based on a polyvinyl chloride sheet (hereinafter simply referred to as "P").
VC sheet) was laminated on a base material, and a soft thin film made of vinyl chloride plastisol or organosol with a thickness of 5 to 30 μm was formed on the PVC sheet to form a protective layer, so it was not included in the above sheet or protective coating. Volatile substances generated from various additives, or decomposition products of resins and additives, do not remain at the laminated interface between the sheet and the protective coating, but permeate through the thin protective coating and dissipate into the outside air. However, deterioration and blackening are prevented.

The base material used in the present invention may be a metal plate such as a steel plate or an aluminum plate, plywood, or a plastic plate, which are commonly used as materials for building materials, and among them, a steel plate is preferably used.

The PVC sheet to be laminated on the above base material is obtained by blending polyvinyl chloride resin with plasticizers, stabilizers, lubricants, colorants, and other additives such as antistatic agents and UV inhibitors as necessary, and then molding the mixture. It is a sheet or a sheet with decorative printing applied, and usually has a wall thickness of about 100 to 500μ.In the present invention, the protective coating formed on the PVC sheet is chlorinated. 5-30 consisting of plastisol or organosol in which vinyl resin is dispersed in a plasticizer
It is a thin film in the μ thickness range.

That is, the above-mentioned plastisol is a sol prepared by dispersing vinyl chloride resin powder such as polyvinyl chloride or vinyl chloride monovinyl acetate copolymer with an average particle size of about 0.8μ and a particle size distribution of about 0.2 to 2 in a plasticizer. It is made into a paste. Examples of plasticizers added to the vinyl chloride resin include diphenyl phthalate (DPP), tricresyl phosphate (TCP), and dioctyl adipate (DOA).
), trioctyl phosphate (TOP), dioctyl phthalate (DOP), dimethyl phthalate (DMP
), etc., and the amount added is in the range of 20 to 80 parts by weight per 100 parts by weight of the vinyl chloride resin. If it is below the above range and is less than 20 parts by weight, the cold resistance and bending workability of a laminate based on a metal plate will be poor in practice, and if it is above the above range and it is more than 80 parts by weight, This causes problems in terms of the adhesiveness of the protective coating and the surface hardness. Furthermore, the organosol used in the present invention is obtained by diluting the plastisol with an appropriate amount of an aliphatic hydrocarbon solvent that does not dissolve the vinyl chloride resin to lower the viscosity of the sol. It may also contain additives such as stabilizers.

Examples of the aliphatic hydrocarbon solvents used as the diluent include petroleum ether (BP: 60-80°C), petroleum benzine (BP: 80-100°C), and ligroin (BP: 10°C).
0-120℃), mineral spirits (BP: 140-
Gasoline such as 220° C.) is suitable. The above plastisol or organosol is applied to the PVC sheet surface using a coating device such as a roll coater or a blade coater, dried at room temperature to form a sol film, and then the sol film is heated to a predetermined temperature to gel and melt. A protective coating film with a film thickness in the range of 5 to 30 μm is obtained. If the film thickness is below the above range and is thinner than 5μ, it will lose its function as a protective film for the laminate.
Conversely, if it exceeds the above range and is thicker than 30μ, it is likely to turn black. As mentioned above, the present invention forms a thin film on the surface of PVC sheets constituting a laminate using plastisol made by dispersing vinyl chloride resin powder with a large amount of plasticizer or organosol made by diluting plastisol with a solvent that does not corrode the resin. As a result, it maintains the excellent properties required for laminates, such as bending workability (for laminates based on metal plates) and cold resistance, and also allows laminates to be used outdoors. In this case, it does not turn black or deteriorate like conventional products, and maintains a good appearance for a long period of time. That is, the protective coating film formed on the laminate protects the surface of the polyvinyl chloride sheet formed on the base material from damage and abrasion for the purpose of rust prevention, pollution prevention, or decoration of the base material, and also protects the surface of the polyvinyl chloride sheet from damage and abrasion. It has the effect of preventing sheet deterioration due to heat and heat and eliminating blackening. The reason for this is thought to be that the volatile substances and decomposition products generated from the sheet as described above are not confined inside but are constantly escaping into the outside air through the thin protective coating. The present invention will be further explained below with reference to Examples, but it goes without saying that the present invention is not limited thereto.

Example 1 200μ thick PVC obtained by calendar molding method
A woodgrain pattern was printed on the surface of the sheet, and plastisol of Formulation A was applied to the printed sheet using a blade coater, followed by drying at room temperature to obtain a protective coating film with a thickness of 30 μm.

Blend A O polyvinyl chloride powder (Zeon 121 manufactured by Nippon Zeon Co., Ltd.)
Straight resin, average degree of polymerization: 1650)...
・・・・・・・・・・・・・・・・・・・・・100 parts by weight 0 Plasticizer (dioctyl phthalate) 80 parts by weight O Calcium stearate ・・・・・・・・・
...1 part by weight O Zinc stearate ...
・・・・・・・・・・・・・・・1 part by weight Next, the protective coating surface of the printed sheet was heated at 185°C for 5 minutes to gel and melt the coating, and then the back side of the sheet was heated. A 2m thick steel plate was laminated on the laminate, and the protective coating surface of the resulting laminate was coated with a standard plate manufactured by Toyo Rika Kogyo Co., Ltd. When irradiated with Sunshine Weather Meter, no discoloration was observed even after 1500 hours.

Note that even when the above-mentioned laminate was bent, no abnormality was observed in the bent portion. On the other hand, when the protective coating film was formed to a thickness of 50 μm, it turned black after approximately 900 hours of irradiation.

Example 2 An organosol having the following formulation B was coated on the surface of the printing sheet used in Example 1 using a blade coater, and dried at room temperature to obtain a protective coating film with a thickness of 15 μm.

Compound B O Vinyl chloride resin powder (Zeon 135J manufactured by Nippon Zeon Co., Ltd.)
Copolymer with vinyl acetate content of 3%)
・・・・・・・・・・100 parts by weight O Plasticizer (tricresyl phosphate)・・・・・・・・・・・・・・・・
・・・・・・・・・・・・40 parts by weight O dibasic lead phosphite ・・・・・・・・・・・・・・・・・・2
Weight part O Regroin・・・・・・・・・・・・・・・
30 parts by weight Next, the surface of the protective coating film was heated at 140°C for 5 minutes to gel and melt the coating film, and then the back side of the printing sheet was heated. 2Trr on the side
Steel plates having a thickness of 1 rL were laminated, and then an irradiation test was conducted in the same manner as in Example 1, and no discoloration was observed even after 1500 hours.

Note that the obtained laminate had no problems in bending workability.

Example 3 An organosol having the following formulation C was coated on the surface of the printing sheet used in the example using a roll coater, and dried at room temperature to obtain a protective coating film with a thickness of 5 μm.

Blend C Polyvinyl chloride powder (Nippon Zeon Co., Ltd. Zeon 121, straight resin, average degree of polymerization: 1650)...
...100 parts by weight plasticizer (dioctyl adipate)
...20 parts by weight dibutyltin malate...
2 parts by weight Mineral spirit...60 parts by weight Next, the above protective coating surface was heated at 160°C for 10 minutes,
After gelling and melting the coating film, 2
When steel plates with a thickness of mm were laminated and the resulting laminate was then heat treated in a hot air dryer set at a temperature of 185°C, no discoloration was observed even after 210 hours.

Note that even when the laminate obtained here was bent, there was no abnormality in the folded portion, and the protective effect of the printed surface was sufficient.

On the other hand, when the thickness of the protective coating is 40μ, the temperature is 185℃,
Coloring started in 90 minutes.

Claims (1)

[Claims] 1. Add 2 parts of plasticizer to 100 parts by weight of vinyl chloride resin on a laminate made of polyvinyl chloride sheets laminated as a base material.
A weather resistance-improved laminate comprising a protective coating film having a thickness of 5 to 30 microns and made of plastisol or organosol containing 0 to 80 parts by weight.