JPH05194690A - Cross-linkable mixture and production of coating agent and molded article using the same - Google Patents

Abstract

PURPOSE:To obtain a cross-linkable mixture providing films having diversity and excellent chemical resistance by blending a polyfunctional amide with a substituted alkoxyalkylamino resin and a reaction diluent and cross-linking the blend in the presence of a strongly acidic catalyst. CONSTITUTION:A mixture of (A) a polyfunctional amide, preferably formamide and (B) a substituted alkoxyalkylamide resin having 400-1,500g/mol molecular weight is mixed with a solvent comprising a resin alcohol, an ether alcohol, a diether and/or a tertiary amide and cross-linked in the presence of 0.10-2wt.% strongly acidic catalyst, preferably aqueous solution of an organic sulfonic acid to give the objective mixture having a weight ratio of the component A: the component B of 5:95 to 75:25 and 10-80wt.% total content of the component A and the component B.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a crosslinkable mixture which is cured over a wide temperature range. This mixture consists of a polyfunctional formamide, an alkoxylated melamine-formaldehyde resin, hereinafter abbreviated as melamine resin, or other similarly reactive amino resin, and a reactive diluent, which is crosslinked after the addition of a strongly acidic catalyst. What is done,
It is preferably used for the production of coating agents and molded products.

[0002]

Amino resins are formaldehyde and active polyamines such as 1,3,5, also known as melamine.
It is a polycondensate with -triamino-2,4,6-triazine, benzoguanamine, glycoluril or urea.
In the process, not only oligomers linked via methylene and ether groups but also free methylol groups are formed, which are lower alcohols, preferably methanol, n-butanol and i-butanol under acid catalysis. Etherified. Crosslinking then occurs by an acid-catalyzed transesterification reaction with a polyol, preferably a polyhydroxyl compound such as polyesters containing hydroxyl groups and polyacrylates. This cross-linking reaction occurs at temperatures in the range of 120-250 ° C. to remove low boiling alcohols such as methanol or isobutanol.

A prominent polymer of this type having excellent coating properties is the melamine-formamide polycondensate, which is etherified by a lower alcohol, preferably methanol, ethanol or n-butanol or i-butanol. . As a result, the amino group is completely alkoxymethylated, or is still free-
Oligomeric product having a NH group or NH-CH ₂ -OH group can be obtained. Depending on the conditions of synthesis, two or more triazine ring CH ₂ - they are connected to each other by bridging bonds, the molecular weight increases.

Non-etherified melamine-formaldehyde adducts have very high reactivity towards polyhydroxyl compounds, but on the other hand the partial elimination of formaldehyde is one drawback. This is an alcohol, preferably n
-Inhibited by etherification with butanol or i-butanol. The crosslinking activity of these melamine resins is reduced from methyl etherification products to butyl etherification products.

Such products are, for example, CYMEL (Amenrican Cyanamid), Resimene
(Monsant), Meprenal (Hoechst
T) company, or Luwinal (BASF) and other known trade names. These are medium to high viscosity colorless products with a free solvent content in the range 2 to 30% by weight.

Melamine resins are very versatile crosslinkers for polyfunctional, low molecular weight and polymerizable hydroxy and carboxy compounds. These are reacted under acid catalysis, preferably with a sulfonic acid, such as paratoluene sulfonic acid and other aromatic sulfonic acids,
It forms a glossy, transparent and chemically very stable coating. Here, an essential step in cross-linking is that a carbocation capable of reacting with —OH group, —COOH group, —CONH ₂ group and with itself is generated from an alkoxymethylolamino group and a proton. According to the American Cyanamide pamphlet (Cymel 303 crosslinker, 1988), this step is represented by the following reaction formula (XXII).
As shown.

[0007]

[Chemical 5]

Generally, the melamine resin has a --OH group, a --COOH group or a --CON group at 90.degree. C. or higher in the presence of a strong acid catalyst.
Crosslinks only with low and high molecular weight compounds containing H ₂ groups. Under such conditions, the -OH group has the highest reactivity. On the contrary, -COOH group and -CON
The H ₂ group reacts only at 130 ° C. or higher in the presence of an acidic catalyst. In addition to this, as a cross-linking active group-
There are SH residues and acetoxy residues. The cross-linking of the aforementioned functional groups with the melamine resin occurs non-stoichiometrically. For hexamethoxymethylmelamine, it is generally speculated that only two of the six methoxymethyl groups participate in the reaction with other reactive functional groups. However, in addition to this, the self-crosslinking of the melamine resin must be considered.

Since melamine resins crosslink with low molecular weight compounds to form brittle films, polymerizable crosslinkers, preferably --OH and --COOH groups, are functionalized to impart the desired mechanical properties to the coating. Polyacrylates and polyesters with groups are used as binders. Such a coating may be 120-150
It is characterized by having excellent weather resistance, light stability, chemical stability and mechanical properties when dried at a temperature of ° C.

[0010]

However, as mentioned above, these conventional crosslinkable resins have a relatively high heating temperature, for example, about 120 to 250 ° C. for the crosslinking. Therefore, there is a disadvantage that the base material to which this can be applied as a paint is limited to those having sufficient heat resistance.

[0011]

The crosslinkable mixture of the present invention comprises (a) at least one multifunctional amide, preferably formamide, and (b) at least one 400 to about 1: 1.
A reactive mixture of substituted alkoxyalkylamino resins having a molecular weight in the range of 500 g / mol and one solvent or solvent mixture selected from the group consisting of aliphatic alcohols, ether alcohols, diethers or tertiary amides; A crosslinkable mixture of 10 to 2% by weight of a strongly acidic catalyst, preferably an aqueous solution of organic sulfonic acid, wherein the weight ratio of (a) :( b) in the above reactive mixture is 5:95 to 75: 25, preferably 10: 90-5
It can be varied within a wide range of 0:50, and the total content of (a) and (b) in the above reactive mixture is 10
-80% by weight, preferably 55-70% by weight. Or (a) at least one multifunctional amide, preferably formamide,
(B) at least one substituted alkoxymethylamino resin having a molecular weight in the range of 400 to about 1500 g / mol,
And (c) a reactive mixture consisting of a cyclic carbonate, and 0.10 to 2% by weight of a strongly acidic catalyst, preferably an aqueous solution of an organic sulfonic acid, which is a crosslinkable mixture,
The weight ratio of (a) :( b) :( c) in the above reactive mixture is 1: 1: 1 to 0.2: 1: 0.2, preferably 0.2: 1: 0.2 to 0. Within a wide range of 5: 1: 0.5, particularly preferably 0.2: 1: 0.5, the total content of (a), (b) and (c) in the above reactive mixture is 85. It is characterized in that it is in the range of up to 100% by weight. Or (a) at least one polyfunctional amide, preferably formamide, (b) at least one alkoxymethylamino resin, and (c) a secondary having 1 to 12 carbon atoms in the aliphatic residue. A reactive mixture of linear or branched aliphatic formamide, 0.
A crosslinkable mixture comprising 10 to 2% by weight of a strongly acidic catalyst, preferably an aqueous solution of organic sulfonic acid, wherein the weight ratio of (a) :( b) :( c) in the above reactive mixture is 1: 1. : 1 to 0.2: 1: 0.2, preferably 0.2:
1: 0.2 to 0.5: 1: 0.5, particularly preferably 0.
Within the wide range of 2: 1: 0.5, the total content of (a), (b) and (c) in the above reactive mixture is 85-85.
It is characterized by being in the range of 100% by weight.

In the present invention, a polyfunctional amide, preferably formamide, is excellent in crosslinking with an amino resin, preferably a melamine resin, in the presence of a strongly acidic catalyst at a wide range of temperatures from room temperature to 150 ° C. It was surprising to find that it produced a transparent, colorless, flexible film with hardness and chemical resistance.

In the present invention, a formamide-melamine mixture having the desired composition is a suitable volatile solvent or a low volatility reactive diluent such as cyclocarbonate, preferably propylene carbonate and a secondary formamide, preferably N-. It can be dissolved in methylformamide. A low viscosity paint is thus obtained and can be applied over a variety of basecoats using conventional paint application techniques. Such a crosslinkable mixture has a molecular weight of 60 to 1,000 g / mol, preferably 90 to 400 g / m.
It consists only of low molecular weight compounds in the ol range,
A three-dimensional network is formed after thermal crosslinking.

Suitable polyfunctional amides, preferably formamides, are aliphatic, cycloaliphatic, aromatic and arylaliphatic monoamines, diamines and polyamines, polyetherdiamines and polyamines, and at least one --OH group. And aminoalcohols having one primary or secondary amine group and are prepared from these compounds by simple reactions, eg transamidation reactions. The resulting amide, in contrast to the starting amine, has low volatility, is physiologically harmless, and is stable to oxidation by atmospheric oxygen and salt formation by carbon dioxide.

Hydroxyalkylformamides, for example
2-Hydroxyethylformamide-2, 1-hydroxy-2-methyl-propylformamide-2, N-formyl-amino-N-formylaminoethanol and N-formyldiethanol have been found to be particularly effective. Diformamides such as ethane-1,2-diformamide, propane-1,2-diformamide, propane-1.3
-Diformamide, hexamethylene-1,6-diformamide, 4.7-dioxadecane-1,10-diformamide and even m-xylenediformamide are suitable crosslinkers for melamine resins.

Particularly advantageous is the use of liquid polyfunctional formamides because they are mostly compatible with melamine resins without other solvents. Solid diformamide,
For example, α, ω-terminated aliphatic diformamides, aromatic diformamides, and aromatic polyformamides having an even number of carbon atoms in the backbone include straight chain and 1 to 4 carbon atoms in the backbone. It dissolves in branched alcohol,
Their solubility decreases as the formamide chain length increases.

All formamides having the structures represented by the following general formulas (I) to (XVII) are substantially suitable as crosslinking agents.

[0018]

[Chemical 6]

[0019]

[Chemical 7]

[0020]

[Chemical 8]

(In the above general formulas (I) to (XVII),
R ₁ is hydrogen or methyl group, R ₂ is alkyl group, aryl group or benzyl group, Ar is an unsubstituted or substituted mononuclear or polynuclear aromatic compound, X is —CH ₂ —, —C
_{(CH 3) 2 -, -} O -, - S- or -SO ₂ -, Y is an alicyclic compound 5- or 6-membered ring which is unsubstituted or substituted. )

Diformamides and polyformamides having the ability to crosslink can be prepared in a suitable solvent such as a ketone,
It can be obtained by reacting monohydroxyalkylformamide and dihydroxyalkylformamide with dipolyisocyanates and polyisocyanates or polyurethane prepolymers having free NCO groups. The products thus obtained are characterized by a molecular weight in the range from 300 to 2,000 g / mol and are usually relatively well soluble in the commonly used coating solvents and their mixtures. Since these products can be produced by numerous combinations of diols and polyols, diamides and polyamides with isocyanates, they are preferably used to improve the adhesiveness, flexibility, etc. of crosslinked materials. Better yet, its utilization characteristics can be improved.

Suitable diisocyanates and polyisocyanates are, for example, hexamethylene diisocyanate,
2,4-toluylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate and their dimerization and trimerization products. Also, diols, diamines or polyamines, oligomers and polymer addition products of polyacrylates and polyesters having hydroxyl groups as functional groups, and still N.
Also suitable are the above-mentioned diisocyanates and polyisocyanates containing CO groups, which compounds are further reacted with monohydroxyalkylformamides or dihydroxyalkylformamides to form urethanes and polyurethanes containing formamide groups.

Still other types of diformamides and polyformamides have ester groups and monohydroxyalkylformamides or dihydroxyalkylformamides can be converted into Schotten-Baumann
By reacting with a chloride of a dicarboxylic acid or a polycarboxylic acid, or by a transesterification reaction, with a dialkyl ester of a dicarboxylic acid, or an ester of a polycarboxylic acid, preferably their methyl ester or ethyl ester. Can be prepared by These products also have improved solubility in paint solvents and exhibit very good compatibility with melamine resins. Suitable dicarboxylic acid dichlorides and diesters are, for example, succinic acid, maleic acid, adipic acid or sebacic acid or dodecane dibasic acid, the isomeric phthalic acid, 1,3,5-benzenetricarboxylic acid, 1,2,4- Obtained from benzenetricarboxylic acid or pyromellitic acid.

Suitable melamine resins are the usual commercial methoxylated, mixed methoxyl-ethoxylated, butoxylated and mixed methoxy-butoxylated products, which can be used with different molecular weights. Further, a product having a free amino group and a product having a non-etherified methylol group can also be preferably used. Cymel 303 is mentioned as an example of a suitable fully methylated melamine crosslinker having a high hexamethoxymethylmelamine monomer content and also has the highest degree of reactivity with formamide. An example of a fully butylated melamine resin is Cymel 1156, but Cymel 11
16 and Cymel 1130 are suitable melamine crosslinkers etherified with methanol / ethanol and methanol / butanol, respectively. Cymel 370 and 1158
Still has free -NH groups remaining due to incomplete methylolation and also crosslinks with polyfunctional formamide. Carboxyl-modified melamine resins such as Cymel 1141 are also excellent as crosslinkers for the formamide. Apart from the particularly suitable melamine resins, other etherified amino resins can also be used, such as urea-formaldehyde resins, glycoluril and benzoguanamine-formaldehyde resins. These examples are UFR-60, Cymel 11 from Dyno Cyanamid Products.
70, 1173 and 1123.

In order to mix the melamine component with the polyfunctional formamide, solvent or reactive diluent, the viscosity of the resin should not exceed 15-20,000 mPa.S. The mixing ratio of the reactive components required for proper crosslinking can be varied within wide limits. Depending on the molecular weight and functionality of formamide, 5 to 75% by weight, based on the melamine resin used,
Formamide crosslinkers, preferably in the range of 10 to 50% by weight, are required. Suitable catalysts are strong acids, preferably 1.0
Aliphatic and aromatic sulphonic acids having the following pKa values, used in a proportion of 0.1 to 2% by weight, based on the total weight of the coating mixture. Particularly preferably, 0.2 to 1.5% by weight of 70% methanesulfonic acid aqueous solution is used.

These mutually incompatible mixtures have a content of 20 to
Blending 45% by weight of solvent, the pot life will be several months,
It is possible to obtain transparent low-viscosity paints that are at least one month long. Solvents which can be used are aliphatic straight-chain alcohols having 1 to 8 carbon atoms, ether glycols, diethers and tertiary formamides or mixtures thereof. Methanol, ethanol, i-propanol,
n-butanol, i-butanol, butyl glycol,
Methoxypropyl glycol, diethylene glycol dimethyl ether, N, N-dimethylformamide, N,
N-dimethylacetamide and N-methylpyrrolidone are given as examples. A particularly preferred solvent mixture is composed of 3 parts n-butanol and 1 part butyl glycol. The above ingredients are mixed using a simple stirring device without significant energy consumption,
It is possible to produce a paint having a transparent fluidity.
The non-volatile components of this paint are in the range of 10-80% by weight, preferably 55-70% by weight.

Such paints are prepared by known methods, for example by dipping, coating, knife coating or spraying, on many metal substrates such as untreated and phosphated steel sheets, tin and aluminum sheets, glass, It can be applied to substrates such as ceramics, paper, wood, chipboard, wood fiberboard and various surface-treated plastics. These base materials are stable in the crosslinking temperature range of 40 to 130 ° C. and have dimensional stability. Then, the coating material is crosslinked in the state of a wet film having a thickness of up to 150 μm, and becomes a transparent film having high hardness and flexibility. A typical drying time for drying such a thick wet film is 10 to 2 at 120 ° C.
0 minutes, 80 ° C. for 30 to 60 minutes, 60 ° C. for 2 to 3 hours. The resulting coating is glossy, colorless and transparent, and is extremely stable against organic solvents such as methyl ethyl ketone and xylene, as well as against water and dilute alkaline solutions.

The paints prepared using the mixtures according to the invention have a relatively low amount of solvent, in contrast to conventional paints having similar rheological properties based on polymers. It seems desirable to formulate coatings with even lower solvent contents, preferably from 0 to 15% by weight. Surprisingly, cyclic carbonates, such as ethylene carbonate, particularly preferably propylene carbonate, have proved to be suitable reactive diluents for the thermally crosslinked mixtures according to the invention. By adding a cyclic carbonate, preferably propylene carbonate, 40 to 15
The content of volatile solvents which can be evaporated at crosslinking temperatures in the range of 0 ° C. can be reduced to 0-15% by weight in the paint. Infrared spectroscopy on films crosslinked at temperatures of 40-130 ° C shows that the cyclic carbonate participates in the crosslinking reaction and does not remain in the film as a low volatility solvent.

The mixing ratio of the three reaction components of melamine resin, hydroxyalkylformamide or diformamide or polyformamide can be freely selected within a wide range. Melamine resin / formaldehyde /
The weight ratio of cyclic carbonate is 1: 1 to 1: 0.2:
A range of 2 is possible, differing only in the crosslinking temperatures available. A range of 1: 0.2: 0.2 to 1: 0.5: 0.5 is advantageous. Mixtures in a weight ratio of 0.2: 1: 0.5 are particularly advantageous and are crosslinked at temperatures in the range 40 to 130 ° C. As catalyst, it is possible to use 0.05 to 2% by weight of said strongly acidic compounds, in particular 70% methanesulphonic acid solution.

The addition of a volatile solvent to compatibilize the crosslinkable mixtures is such that these mixtures are β-hydroxyethylformamide, bis- (2-hydroxyethyl)-.
Hydroxyalkyl formamide, such as formamide,
Or when N-formylethyl-N-formylaminoethanol or propane-1,3-diformamide, diformamide such as 4,7-dioxadecane-1,10-diformamide, or polyurethane containing a formamide group is required. Absent. In such cases, the amount of propylene carbonate required for crosslinking is generally sufficient for thorough mixing.

Since aliphatic and certain aromatic diformamides such as m-xylenediformamide are also soluble in β-hydroxyethylformamide, these diformamide / hydroxyethylformamide mixtures,
Crosslinkable mixtures of melamine resins of different molecular structure and cyclic carbonates, preferably propylene carbonate, are also suitably produced. At this time, the molar ratio of the reactive groups to each other must correspond to the above-mentioned conditions.

The inclusion of volatile solvents is unavoidable because many melamine resins and other suitable amino resins contain from about 10 to 20% by weight of etherified alcohol from their synthesis. Therefore, it is preferable to use a resin containing no solvent. Propylene carbonate may be partially or wholly replaced by secondary formamides, such as N-methylformamide or other N-alkylformamides, in solvent-free mixtures. These low volatility compounds also
It exhibits better solubility in aromatic formamide and polymerizable formamide crosslinkers compared to propylene carbonate. In the composition of the crosslinkable mixture,
These reactive diluents replace some of the multifunctional crosslinker components.

Several chemically different formamide crosslinkers can be combined with at least one melamine resin and propylene carbonate, which makes it possible to adjust certain mechanical properties such as hardness, flexibility and the like. . The aforementioned crosslinkable solvent-containing mixture has a low viscosity and contains up to 70% by weight of crosslinkable components,
It is crosslinked at a temperature of 160 ° C. to give a hard, transparent coating with excellent chemical stability.

Crosslinkable mixtures of polyfunctional formamides, melamines and, preferably, reactive diluents such as propylene carbonate or -alkylformamides and coatings prepared therewith have some excellent properties. . These mixtures consist of low molecular weight compounds and thus have characteristic rheological properties. That is, it has a low viscosity and good spreadability on many substrates. Even for "high molecular weight" melamine resins, the molecular weight is not much higher than 1,000 g / mol.

Compared to coatings based on polymers with similar processability, these crosslinkable mixtures have a significantly lower content of volatile solvents, 0 to 20% by weight, preferably 0 to 10% by weight. %, Which is due only to the solvent content of the melamine resin used. Many suitable melamine resins, such as hexamethoxymethyl melamine, contain up to 2% by weight of volatile solvents, and practically solvent-free mixtures for these resins are possible.
Has a pot life of several months before the viscosity of these mixtures rises appreciably even after addition of 0.5-0.5% by weight of strongly acidic catalyst in a closed vessel at room temperature. . Other additives such as pigments, light stabilizers and other additives may be added to the mixture as needed.

In contrast to solvent-containing mixtures, solvent-free mixtures can be crosslinked in a wide range of temperatures from room temperature to 180 ° C. It has been found that a temperature range of 35 to 80 ° C. at which the coating crosslinks and exhibits dimensional stability is particularly suitable. The fully cured film is colorless, highly transparent, glossy and has excellent resistance to water, organic solvents and dilute alkalis. The cure time is necessarily determined by the crosslinking temperature and the relative humidity of the atmosphere. The higher the relative humidity, the faster the crosslinked coating at temperatures of 35-60 ° C. reaches maximum hardness and solvent resistance. For example, 5% under conditions of relative humidity 25% and 35 ° C
Time-crosslinked films require one week to reach good MEK resistance, but only one day when the relative humidity is 60% and other crosslinking conditions are the same. A similar post-cure effect is observed with increasing König pendulum hardness (DIN 53 157). In general, all films crosslinked below 80 ° C. and still tacky, after curing at room temperature, have more or less varying degrees of relative humidity depending on relative solvent resistance and high hardness.

The curing behavior of these mixtures according to the invention is similar to that of air-dried alkyd resins as used in the preparation of wood coatings in the do-it-yourself field. The advantages of the crosslinkable mixtures according to the invention are the absence of volatile, harmful or offensive odor components, no yellowing, low viscosity of the mixture, good chemical resistance after complete curing and good optical properties. To have specific characteristics. Substrates suitable for use in the present invention are steel, aluminum, glass, pretreated plastics, and especially materials with residual moisture, such as wood, paper, paperboard, leather and textiles.

One or several polyfunctional formamides,
Solvents according to the invention consisting of one or several solvent-free amino resins, preferably melamine resins, and cyclic carbonates, wholly or partly substituted with secondary formamides, preferably N-methylformamide, preferably propylene carbonate. The cross-linkable mixture containing no C can not only be cross-linked in a thin film having a thickness of up to 100 μm, but can also be poured into a mold and cured to form a molded product having a wall thickness of up to 1 cm. These moldings are hard, transparent, colorless and free of bubbles.

Due to the low viscosity of the mixture according to the invention,
It has the ability to fill molds of complex shapes sufficiently and completely. The cross-linking of such a molded article is 60 to 180.
It can be performed in the temperature range of ° C. The rate of curing in this step depends on the crosslinking temperature and the wall thickness. For example, the time required to completely cure a molded product with a wall thickness of 0.5 cm is 60
It takes 12 to 15 hours at 0 ° C, about 4 hours at 80 ° C and about 5 minutes at 150 ° C. In order to reduce the shrinkage of moldings and to eliminate air bubbles, the liquid mixture is first pre-cured in a suitable mold at a temperature of 60-80 ° C. to a molding which is elastic but already dimensionally stable. After that, take out from the mold, and at the temperature of 140-180 ℃
It is preferable to cure for ~ 3 minutes. The mechanical properties of such moldings can be adjusted over a wide range by selecting the formamide and melamine components. Formamides having two or more functional groups are advantageous for dense cross-linking, and low molecular weight hexamethoxymethylmelamine resins having free -NH groups for rapid curing even at relatively low temperatures and Melamine resins are particularly preferred.

The use of the mixtures according to the invention in the production of moldings offers several decisive advantages compared to known resin molding systems. The mixture containing the catalyst has a very high storage stability and a low viscosity.
These mixtures cure at much lower temperatures than in the epoxy / anhydride and phenolic resin systems, for example. Due to the crosslinking, the chemical resistance is considerably better than the moldings made of thermoplastics. Due to the low thermal and mechanical stresses, the required moldings can be made from inexpensive materials and can be reused. Due to the low curing temperature, heat-sensitive parts such as electric parts can be encapsulated under mild conditions. The cured moldings are completely colorless and have a high degree of transparency.

In order to improve the mechanical properties, the mixtures according to the invention can be crosslinked with appropriately pretreated glass fibers, carbon fibers or aramid fibers, polybutadiene lattices, polystyrene lattices or other fillers and reinforcing substances. Yes, but this results in the loss of very good optical transparency. By this method, 80 to 10
After pre-curing the reinforcing plate at a low temperature of 0 ° C., for example, 150 to
It can also be finally cured through a forming process by deep drawing at a relatively high temperature of 180 ° C. The crosslinkable mixture of the present invention is composed of usual commercially available or easily prepared low molecular weight, low volatility and low toxicity compounds, which are completely cured in a wide temperature range from room temperature to 180 ° C. It is possible to obtain a colorless and highly transparent coating or a molded article having excellent chemical resistance.

[0043]

EXAMPLES The present invention will be described in more detail below with reference to examples. Example 1 1.5 g of 2-hydroxyethylformamide and 13.0 g of Cymel 303 hexamethoxymethylmelamine (Dyno Cyanamid)
After dissolution in a mixture of 8.0 g of n-butanol and 2.0 g of butyl glycol and complete homogenization, 0.1 g of a 70% aqueous solution of methanesulfonic acid (Aldrich).
Company). The results of the coating test are shown in Table 1 below.

Example 2 1.5 g of 2-hydroxyethylformamide and 19.0 g of Cymel 303 hexamethoxymethylmelamine (Dyno Cyanamide Co.) were added to 10.
It was dissolved in a mixture of 0 g of n-butanol and 3.0 g of butyl glycol and, after complete homogenization, treated with 0.1 g of 70% aqueous methanesulfonic acid solution (Aldrich).
The results of the coating test are shown in Table 1 below.

(Example 3) 2.6 g of propane-1,3-diformamide and 2.0 g of propylene carbonate were stirred to obtain a transparent solution. While stirring this solution 1
Mixing with 5.6 g of Cymel 303 gave a clear stable mixture. The solvent-free coating was treated with stirring with 0.16 g of 70% aqueous methanesulfonic acid solution. The results of the coating test are shown in Table 1 below.

(Example 4) 2.6 g of propane-1,3-diformamide and 8.0 g of propylene carbonate were stirred to obtain a transparent solution. While stirring this solution 1
Mixing with 5.6 g of Cymel 303 gave a clear stable mixture. The solvent-free coating was treated with stirring with 0.16 g of 70% aqueous methanesulfonic acid solution. The results of the coating test are shown in Table 1 below.

Example 5 4.0 g of the reaction product from 1 mol of isophorone diisocyanate (Huls) and 2 mol of 2-hydroxyethylformamide was added to 6 parts.
Stirring with 4.0 g of propylene carbonate at 0 ° C. gave a clear solution. 7.8 g of this solution
Mixing with el 303 gave a clear mixture. After cooling to room temperature, 0.17 g of 70% aqueous methanesulfonic acid solution was added to this solution. The results of the coating test when the time of post-curing under the conditions of room temperature and 50% relative humidity at two different atmospheric humidity are changed are shown in Table 2 below.

Example 6 An aluminum dish (55 mm x 15 mm) was filled with 6 g of the mixture of Example 5 and (a) 15 ° C. at 15 ° C.
C. (b) 80.degree. C. for 15 hours, (c) 80.degree. C. for 2 hours, removed from the dish and then cured at 160.degree. C. for a further 5 minutes. (a) is flexible, but has dimensional stability.
(b) and (c) were hard. In all the molded articles, the weight loss due to curing was 18 to 20%. The molded product was colorless and transparent, contained almost no air bubbles, and had a smooth and highly glossy surface.

(Example 7) 2.6 g of propane-1,3-diformamide and 8.0 g of propylene carbonate were stirred to obtain a transparent solution. 17.3g C in this solution
ymel 327, free -NH group, solid content 90%
The melamine resin of was mixed with stirring to obtain a transparent and stable mixture. The solvent-free coating was then treated with stirring with 0.16 g of 70% aqueous methanesulfonic acid solution. The results of the coating test are shown in Table 1 below.

Example 8 6.3 g of the mixture of Example 7
Curing in an aluminum dish at 80 ° C. for 15 hours,
A transparent, fracture-resistant molding having a slight surface structure was obtained.

(Example 9) 2.6 g of propane-1,3-diformamide and 8.0 g of propylene carbonate were stirred to obtain a transparent solution. 17.0 g C in this solution
ymel 370, free methylol group, solid content 8
8% melamine resin was mixed with stirring to obtain a transparent and stable mixture. The solvent-free coating was treated with stirring with 0.20 g of 70% aqueous methanesulfonic acid solution. The results of the coating test are shown in Table 1 below.

Example 10 7.4 g of the mixture of Example 9
Was cured in an aluminum dish at 80 ° C. for 15 hours to obtain a transparent molded product having a slight surface structure.

Example 11 0.5 mol of industrial toluene diisocyanate (Bayer), 0.25 mol of 2
-Formamide-2-methylpropane-1,3-diol,
And 4.8 g (0.01 mol) of an oligourethane formed from 0.5 mol of 2-hydroxyethylformamide-1 and 80 to 10
Dissolved in 6 g propylene carbonate at 0 ° C. and mixed with 11.7 g Cymel 303 to give a clear solution. After cooling to room temperature, add 0.3 to a moderately viscous mixture.
g of 70% methanesulfonic acid solution was added. The results of the coating test are shown in Table 1 below.

Example 12 5.2 g of the mixture of Example 7
Was crosslinked in an aluminum dish at 100 ° C. for 2 hours to obtain a hard pale yellow molded product containing almost no bubbles.

Example 13 3.6 g of the adduct of Example 5
Was stirred at 60 ° C. with 3.6 g of propylene carbonate to give a clear solution. This solution and 7.0
g of Cymel 1158, 7.0 g of butoxylated melamine resin with free --NH groups and 80% solids content, were mixed to obtain a clear mixture. After cooling to room temperature, 0.18 g of 70% aqueous methanesulfonic acid solution was added to this mixture. The results of the coating test are shown in Table 1 below.

(Example 14) 4.5 g of the adduct of Example 5
Was stirred at 60 ° C. with 4.5 g of propylene carbonate to give a clear solution. 8.8 with this solution
A clear mixture was obtained by mixing with g Cymel 1158, 80% solids methoxy / ethoxy melamine resin. After cooling to room temperature, 0.29 g of 70% aqueous methanesulfonic acid solution was added to this mixture. The results of the coating test are shown in Table 1 below.

(Example 15) 5.0 g of the adduct of Example 5
Was stirred with 5.0 g of propylene carbonate at 60 ° C. to obtain a clear solution. 9.7 with this solution
A clear mixture was obtained by mixing g of Cymel 1156 and butoxylated melamine resin having a solid content of 100%. After cooling to room temperature, 0.26 g of 70% aqueous methanesulfonic acid solution was added to this mixture. The results of the coating test are shown in Table 1 below.

(Example 16) 3.9 g of the adduct of Example 5
Was stirred at 60 ° C. with 3.9 g of propylene carbonate to give a clear solution. This solution and 9.7g
Cymel 327, which has a free -NH group and a solid content of 1
A transparent mixture was obtained by mixing with 00% melamine resin. After cooling to room temperature, 0.26 g of 7
A 0% methanesulfonic acid aqueous solution was added. The results of the coating test are shown in Table 1 below.

Example 17 Mixture of Example 16 10.
0 g was cured in an aluminum dish at 80 ° C for 18 hours,
A hard colorless and clear molded product was obtained.

(Example 18) 7.8 g of Cymel 303 was added to 1.
Mixing with 5 g of N-methylformamide gave a clear, moderately viscous solution, which was treated with 0.1 g of 70% methanesulphonic acid. The results of the coating test are shown in Table 1 below.

Example 19 1.3 g of propane-1,3-
Diformamide was dissolved in 1.2 g N-methylformamide and mixed with 7.8 g Cymel 303 to give a clear solution. To this solution was added 0.1 g of 70% methanesulfonic acid. The results of the coating test are shown in Table 1 below.

Example 20 3.6 g of the adduct of Example 5
Were prepared and stirred together with 3.6 g of propylene carbonate at 60 ° C. to obtain clear solutions, and 7.0 g of Cymel 303 was mixed with each. After cooling to room temperature, the mixture was mixed with (a) 0.1 g of p-toluenesulfonic acid (p
Ka: 0.70), (b) 0.1 g of dichloroacetic acid (pKa: 1.48) and
(c) Treated with 0.5 g of pivalic acid (pKa: 5.03). Four
After drying at 0 ° C for 16 hours and at 80 ° C for 2 hours, p
-Only the mixture containing toluenesulfonic acid was crosslinked.

(Coating test example) 100 μm of all paints
Was coated on a glass plate with a spiral coating knife and cross-linked in a paint drying cabinet (Heraeus) for given time and temperature conditions. Cross-linking experiments under controlled weather conditions include air-circulation weather cabinets (Weis
s)) in. Resistance to MEK and H ₂ O was measured by rubbing backwards and forwards (double strokes (DS)) using saturated absorbent paper. The König pendulum hardness was measured according to DIN 52157. Both tests were performed 24 hours after crosslinking unless otherwise indicated.

[0064]

[Table 1]

[0065]

[Table 2]

[0066]

[Table 3]

[0067]

Industrial Applicability As described above, the crosslinkable mixture of the present invention is composed of a commercially available or easily prepared compound having a low molecular weight, low volatility and low toxicity.
It can be completely cured in a wide temperature range up to 80 ° C. to obtain a colorless and highly transparent coating or a molded article, or a composite material molded article having excellent mechanical properties and chemical resistance.

Claims (9)

[Claims] 1. A reactive mixture of (a) at least one polyfunctional amide, preferably formamide, and (b) at least one substituted alkoxyalkylamino resin having a molecular weight in the range of 400 to about 1500 g / mol. Consists of one solvent or solvent mixture selected from the group consisting of aliphatic alcohols, ether alcohols, diethers or tertiary amides, and 0.10-2% by weight of strongly acidic catalyst, preferably an aqueous solution of organic sulfonic acid. A crosslinkable mixture, wherein (a) in the above reactive mixture:
The weight ratio of (b) is 5:95 to 75:25, preferably 1
It can be varied within a wide range from 0:90 to 50:50, and the total content of (a) and (b) in the above reactive mixture is 10 to 80% by weight, preferably 55 to 70% by weight. Crosslinkable mixture characterized by a range. 2. (a) at least one polyfunctional amide, preferably formamide, (b) at least one substituted alkoxymethylamino resin having a molecular weight in the range of 400 to about 1500 g / mol, and (c) a cyclic carbonate. A cross-linkable mixture comprising a reactive mixture consisting of 0.10 to 2% by weight of a strong acid catalyst, preferably an aqueous solution of an organic sulfonic acid, wherein (a) :( b) :( The weight ratio of c) is from 1: 1 to 0.
2: 1: 0.2, preferably 0.2: 1: 0.2-0.
Within the wide range of 5: 1: 0.5, particularly preferably 0.2: 1: 0.5, (a) in the above reactive mixture,
The total content of (b) and (c) is 85 to 100% by weight.
The crosslinkable mixture is characterized in that 3. (a) at least one polyfunctional amide, preferably formamide, (b) at least one alkoxymethylamino resin, and (c) having 1 to 12 carbon atoms in the aliphatic residue. A reactive mixture of secondary linear or branched aliphatic formamide, 0.1
A crosslinkable mixture comprising 0 to 2% by weight of a strongly acidic catalyst, preferably an aqueous solution of an organic sulfonic acid, wherein the weight ratio of (a) :( b) :( c) in the above reactive mixture is 1:
1: 1 to 0.2: 1: 0.2, preferably 0.2: 1:
0.2-0.5: 1: 0.5, particularly preferably 0.2:
Within a wide range of 1: 0.5, the total content of (a), (b) and (c) in the above reactive mixture is 85-10.
Crosslinkable mixture, characterized in that it is in the range of 0% by weight. 4. The polyfunctional amide is preferably a formamide having any one of the structures represented by the following general formulas (I) to (XVII).
The crosslinkable mixture according to any one of to 3. [Chemical 1] [Chemical 2] [Chemical 3] (In the general formulas (I) to (XVII), R ₁ is hydrogen or a methyl group, R ₂ is an alkyl group, an aryl group or a benzyl group, Ar is an unsubstituted or substituted mononuclear or polynuclear aromatic compound, X is _{-CH 2 -, - C (CH} 3) 2
—, —O—, —S— or —SO ₂ —, Y is an unsubstituted or substituted 5-membered or 6-membered alicyclic compound. ) 5. The substituted alkoxymethylamino resin having a molecular weight in the range of 400 to about 1500 g / mol is substituted with at least one different substituent having a structure represented by the following general formulas (XVIII) to (XXI). The crosslinkable mixture according to any one of claims 1 to 3, which is a thing. [Chemical 4] (In the above general formulas (XVIII) to (XXI), A is 1,3,5
- substituted triazine ring, 3,5-substituted 1-phenyl-triazine ring, represents a tetrasubstituted glycoluril ring and urea formaldehyde polycondensates, R represents -H, -CH _3, -C
_{It represents 2} H ₅ , n-C ₄ H ₉ or i-C ₄ H ₉ . ) 6. The crosslinkable mixture according to claim 2, wherein the cyclic carbonate is propylene carbonate. 7. Use of the crosslinkable mixture according to any one of claims 1 to 3 and, if necessary, new additives such as pigments, light stabilizers and other additives at room temperature for at least 1 month. Has a pot life of preferably 3 to 4 months and is applied to a non-metal substrate such as glass, plastic, wood, leather, paper or textile material, and has a range of 20 to 150 ° C, particularly preferably 40 to 80 ° C. A method for producing a coating agent, which comprises cross-linking at a temperature of 1 to obtain a coating agent having very good chemical resistance, water resistance and mechanical properties. 8. When using the crosslinkable mixture according to any one of claims 2 and 3 and, if necessary, new additives and reinforcing agents in casting in an open or closed mold, A colorless transparent, bubble-free molded article, which is first cured to some extent at a temperature in the range of 60 to 130 ° C., preferably at 60 to 90 ° C., and then at 150 to 180 ° C. for 2 to 3 minutes. A method for producing a molded article, which comprises: 9. A cross-linkable mixture according to claim 2 or 3 made of glass fiber for producing a composite material,
It is cured with a mat of carbon or aramid fibers or an elastomer latex and optionally other additives such as coupling agents to form a resilient but already dimensionally stable plate, which is then A composite characterized by being cured after the molding step or during molding at a temperature in the range of 150 to 180 ° C. to obtain a composite molded article with good mechanical properties and very good chemical resistance. Material Manufacturing method of molded products.