JPH06287258A - Raw material for resin composition of decorative laminated sheet, resin composition of decorative laminated sheet and decorative laminated sheet using thereof - Google Patents

Abstract

PURPOSE:To provide the subject raw material composition consisting of a polymerizable compound containing a specific amount of a specific (meth) acrylate prepolymer and a curing stimulating agent and excellent in resistance of discoloration with age and easiness in a management, e.g. storage. CONSTITUTION:The objective raw material composition capable of curing by the addition of a curative agent and consisting of (A) a polymerizable compound compounded with (meth)acrylate prepolymer having a triazine ring of an average molecular weight of 200-8,000 which is synthesized from an aminotriazine compound, paraformaldehyde and 2-hydroxyethyl (meth)acrylate and expressed by formula I [R<1> is phenyl, methyl, cyclohexenyl, cyclohexyl, etc.; R<2>, R<3>, R<4> and R<5> are -CH2- or -CH2OCH2-; R<6> and R<7> are hydroxyl group or group of formula II (R10 is hydroxy or methyl); (n) is 1-10] in an amount of >=5wt.% based on the total amount of the polymerizable compound and (B) a curing promoting agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel triazine ring-containing acrylate prepolymer or triazine ring-containing methacrylate prepolymer
The abbreviated as "triazine ring-containing (meth) acrylate prepolymer"} was used, a decorative board resin composition raw material, a decorative board resin composition obtained from the raw material, and the decorative board resin composition were used. Regarding veneer.

[0002]

2. Description of the Related Art Conventionally, a decorative board having an unsaturated polyester resin applied and cured on the surface thereof has been widely used as a surface material for furniture such as tables, counters, wall surfaces and the like.

[0003]

However, in these conventional decorative boards, since the unsaturated polyester resin on the surface has a large discoloration property (yellowing) on the surface, discoloration occurs in the stock before or after shipping in the distribution process. The color tone may change depending on the length of the day, which was a problem. It was difficult to prevent this discoloration with time even by improving the storage environment such as storing in a dark place.

When the color tone changes with time in this manner, the products of which the production period has been delayed or the products of different storage environments have different color tones. Therefore, when old lot products and new lot products are sold in a mixed manner and are mixedly installed on a wide wall surface, etc., the variation in the degree of discoloration of each decorative board may significantly impair aesthetics. was there.

[0005] Therefore, for example, products which have been manufactured later are preferably stored in the same lot so as not to be used in the same place as much as possible. Was there. The present invention is to provide a resin composition for a decorative board and a decorative board with improved discoloration with time.

[0006]

[Means for Solving the Problems] That is, the gist of the invention according to claim 1 is for a decorative board which comprises one or more kinds of polymerizable compounds and a curing accelerator, and which is cured by the addition of a curing agent. In the resin composition raw material, an aminotriazine compound, paraformaldehyde, and 2-
Synthesized from hydroxyethyl (meth) acrylate,
A triazine ring-containing (meth) acrylate prepolymer represented by the following formula (1) and having an average molecular weight of 200 to 8000:
It is a raw material for a resin composition for decorative board, which is blended so as to be 5% by weight or more with respect to the total amount of the polymerizable compound.

Formula (1):

[0008]

[Chemical 4]

However, n = 1 to 10. R ₁ is a functional group selected from the group of monovalent or polyvalent functional groups represented by the following formula (2). Formula (2):

[0010]

[Chemical 5]

R _{2 to} R ₅ , R ₈ and R ₉ are --CH _2- , --C
H ₂ OCH ₂ — is a functional group selected from the group consisting of a divalent functional group and a hydrogen group represented by H ₂ OCH ₂ —, and is a functional group selected from the group consisting of two or more species. Among them, —CH ₂ OCH ₂ — bonds triazine rings together. It is a functional group only for. R ₆ and R ₇ are monovalent functional groups selected from a functional group group having a hydroxyl group and an ethylenically unsaturated bond including the formula (3), and among R _{2 to} R ₅ , R ₈ and R ₉ , It is bonded as an end group to —CH ₂ — which does not bond to another triazine ring.

Formula (3):

[0013]

[Chemical 6]

However, at least one functional group of formula (3) is present in the molecule, and R ₁₀ thereof is a hydrogen group or —CH ₃
Is a functional group selected from the group Further, the gist of the invention according to claim 2 is a resin composition for decorative boards, characterized in that a curing agent is added to the resin composition raw material for decorative boards according to claim 1.

Further, the gist of the invention according to claim 3 resides in a decorative board surface-treated with the resin composition for decorative board according to claim 2. The details of the present invention will be described below. First, the raw material and synthesis of the triazine ring-containing (meth) acrylate prepolymer, which is a component of the raw material resin composition for decorative board of the first invention, will be described. (1) 2-Hydroxyethyl (meth) acrylate 2-hydroxyethyl (meth) acrylate is an expression that includes both 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate, as described above. In the invention, it does not mean that both are used alone, but that each is used alone. Hereinafter, "(meta)" has the same meaning.

In addition to the 2-hydroxyethyl (meth) acrylate, if necessary, a compound having an ethylenically unsaturated bond having at least one hydroxyl group, such as 2-hydroxypropyl (meth) acrylate, polyethylene glycol. Mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, trimethylolpropane mono (meth) acrylate, trimethylolpropane di (meth) acrylate,
Allyl alcohol, ethylene glycol allyl ether, glycerin (mono, di) allyl ether, N-methylol (meth) acrylamide, etc., or a mixture thereof can be added. The term "(mono, di)" means both glycerin monoallyl ether and glycerin diallyl ether. Again, this does not mean that both are used together, but that each is used alone. (2) Aminotriazine Compound “Aminotriazine” is a compound having a structure in which an amino group is bonded to each of the three carbon atoms of a triazine ring made of C ₃ N ₃ , and the aminotriazine compound is aminotriazine itself or aminotriazine. A triazine derivative is shown.

Examples of the aminotriazine itself include melamine, and examples of the aminotriazine derivative include benzoguanamine, acetoguanamine, cyclohexanecarboguanamine, cyclohexenecarboguanamine, norbornanecarboguanamine, and nobornenecarboguanamine.

In the synthesis of the prepolymer, any of the aminotriazine compounds may be used alone or as a mixture thereof. However, in addition to this, other compounds that can react with formaldehyde (for example, ureas, ketones, phenols, etc.) for the reason of required characteristics and cost are reacted with formaldehyde in the same system as the reaction system of the aminotriazine compound. May be. (3) Paraformaldehyde It is a solid at room temperature and is used as a formaldehyde source. In the present invention, since it can be used by dissolving it in 2-hydroxyethyl (meth) acrylate together with the aminotriazine compound, the dehydration and desolvation steps are basically unnecessary. Further, during the reaction for synthesizing the prepolymer, unreacted paraformaldehyde is gasified into formaldehyde and is released from the reaction product, so that the unreacted paraformaldehyde recovery process is not particularly necessary. (4) Prepolymer Synthesis Reaction The triazine ring-containing (meth) acrylate prepolymer of the present invention comprises a methylol group introduced into an aminotriazine compound by paraformaldehyde and a hydroxyl group in 2-hydroxyethyl (meth) acrylate. Dehydration condensation etherified by the reaction, or
It is understood that the compound is dehydrated and condensed etherified by the reaction of an aminotriazine compound and 2-hydroxyethyl (meth) acrylate to formaldehyde hemiacetal.

In this prepolymer synthesis reaction, 2-hydroxyethyl (meth) acrylate is liquid at room temperature without using a solvent. Therefore, if the aminotriazine compound and paraformaldehyde are dissolved in it,
It is possible to carry out an efficient reaction in one system.
However, in some cases, it may be carried out by adding an appropriate amount of toluene, alcohol, alcoholic formalin or the like in order to facilitate the reaction such as viscosity reduction and azeotropic distillation with water.

The molar ratio of the aminotriazine compound, paraformaldehyde, and 2-hydroxyethyl (meth) acrylate at the time of synthesis was determined by the kind of raw materials,
When a typical melamine as an aminotriazine compound is used for the reaction in the absence of a solvent, the melamine: paraformaldehyde = 1: 2 or more is preferable, and the melamine: 2 is different depending on the desired physical properties of the cured product. -Hydroxyethyl (meth) acrylate = 1: 2 or more is preferable.

When the ratio of paraformaldehyde to melamine is low, or when the ratio of 2-hydroxyethyl (meth) acrylate to melamine is low, the solubility of melamine is poor and gelation due to self-condensation of melamine is likely to occur. The prepolymer synthesis reaction proceeds by a condensation reaction. The progress of this reaction is indicated by the amount of water released by the condensation reaction. Therefore, the condensation reaction can be stopped at a desired stage by observing this water content and stopping the further water distillation when the desired water content is distilled. The rate of water distillation varies depending on the reaction temperature, stirring efficiency, catalyst, amount of air blown, solvent and the like.

The prepolymer synthesis reaction can be carried out without a catalyst, but in order to accelerate the solubility and / or the etherification reaction of the raw material aminotriazine compound, caustic soda, sodium carbonate, ammonia, triethylamine are added at the time of charging. Organic / inorganic alkali such as
Alternatively, an inorganic or organic acid such as paratoluenesulfonic acid or hydrochloric acid, which is a general etherification catalyst, can be used during charging or during the reaction.

In this reaction system, an ethylenically unsaturated bond is always present. Therefore, during the synthesis of the prepolymer, gelation may occur due to the addition polymerization of the ethylenically unsaturated bond. In order to prevent the gelation, a phenol type or amine type ethylenically unsaturated bond polymerization inhibitor may be added, or oxygen having a polymerization inhibiting action may be blown into the reaction system to carry out the synthesis reaction. Of course, both a polymerization inhibitor and oxygen may be used. In particular, it is desirable to use air, which is industrially easy, for blowing oxygen into the reaction system. In addition, the blowing of these is also preferable in order to promote the evaporation of water by the condensation reaction and to move the equilibrium to the ether bond formation side.

The reaction temperature for preventing the gelation and proceeding the reaction is about 50 to 150 ° C., particularly preferably about 70 to 130 ° C., and the preferable reaction time is about 0.5 to 10 hours. Is. The reaction may be carried out under reduced pressure in order to accelerate the evaporation of water. (5) Product (prepolymer) The triazine ring-containing (meth) acrylate prepolymer thus produced has a (meth) acrylate group and an alkyl ether group and / or
Alternatively, it is a compound containing a methylol group and / or an amino group and / or a methylene group.

As described above, the average molecular weight is controlled within the range of 200 to 8000 by adjusting the charging and / or reaction temperature and / or the amount of water distilled. When the average molecular weight exceeds 8000, the viscosity is high,
Difficult to use. If it is less than 200, a prepolymer having sufficient performance cannot be obtained.

These compounds are usually obtained as colorless and transparent viscous liquids, which do not necessarily need to be purified, but may be purified by means such as washing with water depending on the purpose of use. next,
The raw material for the resin composition for decorative boards, which is characterized by blending the triazine ring-containing (meth) acrylate prepolymer obtained above, will be described.

The resin composition raw material for decorative board of the present invention can be obtained by blending the above-mentioned triazine ring-containing (meth) acrylate prepolymer alone or in combination with another polymerizable compound and a curing accelerator. Further, it is preferable to add a polymerizable monomer for adjusting the viscosity.

The polymerizable compound which can be used in combination is, for example, unsaturated polyester, monofunctional or polyfunctional (meth)
Examples thereof include acrylic oligomers and monofunctional or polyfunctional allyl oligomers, but are not particularly limited thereto. As the curing accelerator, metal soaps represented by cobalt naphthenate, tertiary amines, β-diketones, mercaptans and the like can be used, but the curing accelerator is not particularly limited thereto.

Examples of the polymerizable monomer for adjusting the viscosity include styrene, vinyltoluene, α-methylstyrene, P
-Terbutyl styrene, divinylbenzene, vinyl acetate, monofunctional or polyfunctional (meth) acrylic acid ester, diallyl phthalate and the like can be used, but not limited thereto.

In addition to the above, stabilizers, ultraviolet absorbers, air blocking agents, air curing agents, flame retardants,
Colorants, fillers and the like can be added. Examples of the stabilizer include hydroquinone, t-butylcatechol,
Polymerization inhibitors such as t-butyl hydroquinone and p-benzoquinone, and antioxidants such as phosphoric acid esters can be used.

As the ultraviolet absorber, benzotriazole type, salicylate type, hydroxyaryl type,
A compound such as a benzophenone type can be added in advance. Paraffin wax can be used as the air blocking agent, and an aryl ether compound or the like can be used as the air curing agent.

The colorant is not particularly limited, but for example, titanium oxide, various pigments and dyes, or various commercially available color pastes can be used. As the flame-retardant material, it is effective to use phosphorus, a halogen compound, aluminum hydroxide or the like. Examples of the filler include calcium carbonate, aluminum hydroxide, silica, talc, glass fiber, metal powder and the like.

It should be noted that it is also possible to add saturated polyester, isocyanates, various plasticizers, etc. as the non-polymerizable compound for modification according to the purpose of use. Next, the resin composition for decorative boards will be described. The decorative board resin composition is obtained by adding a curing agent to the above decorative board resin composition raw material.

The curing agent may be selected from peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide, acetylacetone peroxide, acetoacetic acid ester peroxide, and benzoyl peroxide, either alone or in combination. The curing agent is not limited to these.

The resin composition for decorative boards, which depends on the type of the curing agent and the ambient temperature, starts polymerization and curing reaction immediately after addition of the curing agent and gels in about 100 to 700 seconds. Therefore, it is preferable to add a curing agent at the time of applying to the decorative board to obtain a resin composition for decorative board. The compounding ratio of the curing agent depends on the type, but is about 1 wt% with respect to the resin composition raw material for decorative board. However, when the temperature of the construction environment is low, such as in winter, the curing time becomes longer, so it is preferable to increase the amount somewhat.

Next, a decorative board using the resin composition for decorative board will be described. The decorative board of the present invention is (1) spread a transparent or colored liquid resin composition for a decorative board on a plate-shaped substrate.

(2) After coating the resin composition for decorative boards that has been spread with a release film, the resin composition for decorative boards is spread over the entire surface of the substrate by pressing on the release film to obtain a uniform thickness. Spread. (3) Wait for the resin composition for decorative boards to cure.

(4) After the resin composition for decorative boards is cured,
The release film is peeled off. It is manufactured in the process of. The base material used in the present invention is not particularly limited, and wood-based, inorganic-based and metal-based particle boards, fiber boards, plywood, natural boards, calik boards, metal boards and the like can be used. These plate materials may be used as a base material as they are, or titanium paper, printing paper,
A pressure plate sheet film, a decorative sheet such as a metal foil, or the like may be used as the base material.

The spreading on the base material is carried out by pouring a predetermined amount of the resin composition for decorative board directly onto the base material from the container, but it may be applied using a brush or the like. For spreading, it is easy to spread the resin composition for decorative boards in the front, rear, left and right by moving the roller or the base material by a mechanical roller, but the coating film should have a uniform thickness. However, other means may be used. If the thickness of the coating film becomes non-uniform, color shading may occur partially, and variations in color tone due to differences in light transmittance may occur. Therefore, it is preferable to make the thickness as uniform as possible.

As the release film, a usual molded film such as a vinylon film or a polypropylene film is used, but the film may be embossed so as to have moldability. Since the curing time of the resin composition for decorative boards varies depending on the type and blending degree of the curing agent and the curing accelerator, it is advisable to determine an appropriate curing time in advance by experiments or the like.

The peeling of the release film is not limited as long as it does not damage the decorative plate. Also,
Since there is no problem even if it is not peeled off until the time of use, the effect of protecting the resin surface at the time of transportation and storage by the release film can be obtained by doing so. The decorative board obtained in the present invention has excellent resistance to discoloration over time, but the compounding ratio of the triazine ring-containing (meth) acrylic prepolymer in the resin composition for decorative board to be used is 5 wt% based on all polymerizable compounds. If it is less than%, the discoloration resistance with time may be inferior. When the compounding ratio of the triazine ring-containing (meth) acrylic prepolymer in the resin composition for decorative boards is 5 wt% or more based on all polymerizable compounds, good discoloration resistance over time can be obtained. A particularly preferable compounding ratio is 20 wt% or more. The whole amount of the polymerizable compound may be the triazine ring-containing (meth) acrylic prepolymer.

[0042]

EXAMPLES Examples will be described below. 1. Synthesis of triazine ring-containing methacrylate polymer 2-hydroxyethyl methacrylate 781 g (6 mol), melamine 126 g (1 mol) in a separable flask equipped with a stirrer, a thermometer, a gas blowing pipe, and a cooling pipe for distilling fractions. 189 g of 95% paraformaldehyde (6 mol as formaldehyde), paratoluenesulfonic acid 3.
0 g was added and the temperature was raised while blowing air. After the melamine and paraformaldehyde were dissolved in 2-hydroxyethylmethacrylate, the reaction was continued until the amount of water distilled out was 108 g (6 mol) while maintaining the internal temperature at 90 to 120 ° C. The obtained triazine ring-containing methacrylate prepolymer had a bromine number of 92.1 (Brg / 100 g) and a Hazen color number of 10 or less.

The above 1. Examples of resin composition raw materials for decorative boards using the triazine ring-containing methacrylate prepolymer synthesized in Example 1 are shown in Table 1 as Examples 1 to 7. In addition, the same table shows the resin composition raw material for decorative board of Comparative Example 1.

[0044]

[Table 1]

In the table, the room temperature gelation time is
This is the gelling time when a curing agent is added to the decorative plate resin composition raw material to form a decorative plate resin composition. Next, a method for producing a decorative board using the resin composition material for decorative board of the present invention shown in Table 1 and the resin composition material for decorative board obtained from the resin composition material for decorative board of Comparative Example will be described.

The base material was 80 g / ply on a 2.7 mm thick plywood.
It is a paper-laminated board in which white titanium paper of m ² is adhered with an unsaturated polyester adhesive. On the plywood, 1 wt% of methyl ethyl ketone peroxide (Kayamek A manufactured by Kayaku Akzo Co., Ltd.) as a curing agent was added to each of the resin composition raw materials for decorative boards of Examples 1 to 7 and Comparative Example 1 shown in Table 1. Then, the obtained resin composition for decorative board was applied to a substrate at an ambient temperature of 25 ° C., covered with a vinylon film, and uniformly rolled so that the coating film thickness became about 70 μ. After the coating film gelled, it was left in an atmosphere of 40 ° C. for 2 hours to cure the resin composition for decorative board, and then the film was peeled off.

The characteristics of the decorative boards prepared from the resin compositions for decorative boards of Examples 1 to 7 and Comparative Example 1 are shown in Table 2 as Examples 8 to 14. Examples 8-14 are the same as Examples 1-7.
The resin composition for a decorative plate, which was obtained from the resin composition raw material for a decorative plate, of 1. Similarly, Comparative Example 2 shown in the same table corresponds to Comparative Example 1.

The degree of discoloration (yellowing) in the table is represented by the b value in the Hunter color difference formula (Lab). The larger the b value, the larger the yellowness.

[0049]

[Table 2]

As is clear from Examples 8 to 14 and Comparative Example 2, the decorative boards using the resin composition for decorative boards of the present invention have good resistance to discoloration over time. Moreover, it has been shown that the resin composition for decorative boards of the present invention brings good resistance to discoloration to decorative boards. In particular, the use of copper-based metal soap as the curing accelerator further improves the discoloration resistance over time.

In the above examples, the triazine ring-containing methacrylate prepolymer was used. However, the use of the triazine ring-containing acrylate prepolymer or the combination of the triazine ring-containing methacrylate prepolymer and the triazine ring-containing acrylate prepolymer was used. Can also be implemented. Also in these cases, the same effect as that of the above-described embodiment is produced.

In the above, only the synthesis example of the triazine ring-containing methacrylate prepolymer is shown. Similarly to, by using 2-hydroxyethyl acrylate instead of 2-hydroxyethyl methacrylate, the triazine ring-containing acrylate prepolymer usable in the first invention can be synthesized.

[0053]

As described in detail above, the decorative board resin composition obtained from the decorative board resin composition raw material of the present invention provides a decorative board with good discoloration resistance with time. Further, the decorative board of the present invention has good resistance to discoloration over time.

Therefore, in the decorative board according to the present invention,
Since the change in color tone over time is slight, even if the product is manufactured at a later time or has a different storage environment, the color tone is not different for each product. Therefore, even when products of various lots are mixed and installed, the obstruction of aesthetics due to the variation in color tone is prevented.

Further, shipping, storage, construction, etc. for each lot are not necessary, so that the effect of being free from the troublesomeness of management can be obtained together.

Claims (3)

[Claims] 1. A raw material for a resin composition for a decorative board, which comprises one or more kinds of polymerizable compounds and a curing accelerator and is cured by the addition of a curing agent, wherein an aminotriazine compound, paraformaldehyde, and 2-hydroxyethyl are used. An average molecular weight of 200 to 800 represented by the following formula (1) synthesized from (meth) acrylate.
A triazine ring-containing (meth) acrylate prepolymer of 0 was blended in an amount of 5% by weight or more based on the total amount of the polymerizable compounds, and a resin composition raw material for decorative board. Formula (1): However, n = 1 to 10. R ₁ is a functional group selected from the group of monovalent or polyvalent functional groups represented by the following formula (2). Formula (2): R _{2 to} R ₅ , R ₈ and R ₉ are —CH ₂ —, —CH ₂ OCH ₂ —.
In a divalent functional group and a functional group selected one or more from the group of hydrogen radicals represented, of which, -CH ₂
OCH ₂ — is a functional group only for connecting the triazine rings. R ₆ and R ₇ are monovalent functional groups selected from a functional group group having a hydroxyl group and an ethylenically unsaturated bond including the formula (3), and among R _{2 to} R ₅ , R ₈ and R ₉ , It is bonded as an end group to —CH ₂ — which does not bond to another triazine ring. Formula (3): However, at least one functional group of formula (3) is present in the molecule, and R ₁₀ thereof is a hydrogen group and a functional group selected from the group of —CH ₃ . 2. A resin composition for decorative boards, which is obtained by adding a curing agent to the resin composition raw material for decorative boards according to claim 1. 3. A decorative board having a surface resin processed with the resin composition for decorative board according to claim 2.