JPH0674372B2 - Melamine resin molding material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention shows excellent improving properties and a good balance of these properties for molding applications of melamine-based resin molded products such as various compression molded products. The present invention relates to an improved melamine-based resin molding material that also serves as a material.

In particular, the present invention is suitable without adversely affecting preferable properties such as heat resistance, hardness, high gloss, crack resistance, weather resistance, light resistance, stain resistance, and electrical properties of the melamine-based resin molding material. With excellent discretionary disc flow characteristics and suitable minimum mold pressure characteristics, and with excellent bleed-out prevention and mold release properties of polyoxyalkylene-based modifiers that are difficult to achieve at the same time. The present invention relates to a melamine-based resin molding material that has well-balanced improvement properties such as suitability, bleed-out prevention property, and mold release property.

More specifically, the present invention provides (I) the following (a) and (b), (a) a melamine / formaldehyde resin, and (b) the above (a) melamine / formaldehyde resin, and (a) urea / formaldehyde. -Based resin and / or (b) 100 parts by weight of a melamine-based resin selected from the group consisting of a mixed resin composed of ureas, (II) a polyoxyalkylene group, and a saturated or unsaturated group having 8 to 20 carbon atoms. A polyoxyalkylene-based compound containing in the same molecule a group composed of a saturated higher aliphatic compound
The present invention relates to a melamine-based resin molding material characterized by being mixed with 0.4 to 3 parts by weight.

[Prior art]

Heretofore, several proposals regarding the use of polyoxyalkylene-based modifiers have been known in the technical field of melamine-based resins.

For example, Japanese Examined Patent Publication No. 36-22883 shows that the mold shrinkage (mould
Polyoxyalkenes such as polyethylene glycol having a molecular weight of 200 to 1500 or polypropylene glycol having a molecular weight of 150 to 500 in a urea and melamine resin initial condensate for the purpose of reducing shrinkage) and after-shrinkage. On the other hand, there has been proposed a method for producing a modified urea and melamine resin molding material having a small shrinkage, particularly a small shrinkage after molding, which is characterized in that it is added as a modifier in an amount of about 0.5 to 7%.

In this proposal, there is no mention of the polyoxyalkylene compound modifier of the present invention, and it is a technical idea to combine excellent moldability with bleed-out prevention property and mold release property of the modifier. No suggestion is disclosed regarding the problem and its solution. The use of the low molecular weight polyethylene glycol or polypropylene glycol modifier disclosed in this proposal cannot solve the above problems.

In addition, in Japanese Examined Patent Publication No. 39-1808, degassing in the molding process becomes easy, and undesired gaseous substances such as formaldehyde and water remain in the molded product, and a "striped" pattern is generated. For the purpose of preventing deterioration of quality and at the same time improving the moldability of the molding material, a filler such as amino resin initial condensate and pulp, a curing catalyst, a lubricant, a plasticizer, a colorant, or other additives is used. 0.1 to 1 for the final molding material when manufacturing amino resin molding materials
0% polyethylene glycol (average molecular weight 2,000 to 1
A method for producing an amino resin molding material has been proposed, which comprises using an initial condensate solution to which 0,000) has been added at any stage of the reaction.

Also in this proposal, there is no mention of the polyoxyalkylene compound modifier of the present invention, and it is a technical idea to combine excellent moldability with bleed-out prevention property and mold release property of the modifier. There is no suggestion of the problem and its solution. Even if a polyethylene glycol modifier having a higher molecular weight than the above proposal of this proposal is used, the above problems cannot be solved yet.

Further, in British Patent No. 851,295, the following formula HO · CH ₂ · CH ₂ (O · CH ₂ · CH ₂ ) _n OH, where n is 15 to 170 and the amount of amino group (—NH ₂ ) per A thermosetting composition comprising an aminotriazine-aldehyde resin modified by incorporating a polyethylene glycol represented by the following formula having an aldehyde group (-CHO) of 0.43 to 2 has been proposed.

As mentioned above, this proposal has an average molecular weight (n) of about 70.
Only the use of polyethylene glycol modifiers corresponding to 0 to about 7500 is disclosed, and no reference is made to the polyoxyalkylene compound modifiers of the present invention. This proposal refers to improvements in plasticity, flowability, meltability, dimensional stability, crazing resistance, etc., but it also has excellent moldability as well as bleed-out prevention and release properties of the modifier. There is no suggestion of a technical problem to solve the problem and its solution, and the problem cannot be solved as described in the above-mentioned prior proposal.

[Problems to be solved by the invention and means therefor]

The present inventors have conducted research and development on an improved melamine-based resin molding material suitable for producing an excellent molded product with a shortened molding cycle.

As a result, 100 parts by weight of the melamine-based resin selected from the group consisting of (a) and (b) and a specific polyoxyalkylene-based compound in an amount of 0.4 to 3 parts by weight are used to mold the melamine-based resin. The material has excellent moldability indicated by appropriate disc flow characteristics and appropriate minimum imprinting pressure characteristics, without adversely affecting the preferable properties as described above as the melamine-based resin molding material, In addition, it is possible to combine the bleed-out prevention property of the polyoxyalkylene-based modifier which is difficult to be compatible with the mold release property at the time of molding with an excellent improving effect, and further, these excellent moldability, bleed-out prevention property, and It was discovered that the melamine-based resin molding material has well-balanced improvement properties such as releasability.

According to the research conducted by the present inventors, when the polyoxyalkylene compound modifier specified by the present invention is added to the molding melamine resin, the amount of the polyoxyalkylene compound specified in the present invention is If the conditions are important and the above conditions are not satisfied, it will be extremely difficult to achieve both excellent moldability and satisfactory bleed-out prevention and satisfactory releasability. It was

Bleed-out of the polyoxyalkylene-based modifier causes contamination of the molding die, making it impossible to carry out the joint molding operation, and also causes problems such as lower gloss of the molded product, skin blemishes, and deterioration of stain resistance. In addition, the deterioration of releasability makes it impossible to adopt a shortened molding cycle,
Not only further promoting the above problems when attempting to shorten, but problems such as molding failure and deterioration of the physical properties of the molded product cannot be avoided, leading to a loss of the molding purpose, but satisfying the compounding amount conditions specified in the present invention. Therefore, it is possible to combine the modifier bleed-out prevention property and the releasability, which have excellent moldability and are difficult to be compatible with each other, with a satisfactory improvement effect in a well-balanced manner. Wakatsuta.

Therefore, an object of the present invention is to provide a melamine-based resin molding material having the above-mentioned various improved properties.

These and many other objects and advantages of the present invention will become more apparent from the description below.

〔Constitution〕

The melamine-based resin molding material of the present invention comprises (I) the following formulas (a) and (b), (a) melamine / formaldehyde-based resin, and (b) the above (a) melamine / formaldehyde-based resin, ) Urea / formaldehyde resin and / or (b) 100 parts by weight of melamine resin selected from the group consisting of urea and mixed resins, (II) polyoxyalkylene group, and 8 to 20 carbon atoms A polyoxyalkylene-based compound containing a saturated or unsaturated higher aliphatic compound-containing group in the same molecule.
It is a melamine-based resin molding material characterized by being mixed with 4 to 3 parts by weight.

The melamine / formaldehyde resin of the above structural requirement (I) (a) is a melamine alone or a mixture of melamine and a urea and / or a melamine cocondensation component consisting of an amino component other than urea and urea. On the other hand, formaldehyde alone or a mixture of formaldehyde and one or more aldehyde components other than formaldehyde can be obtained by condensation reaction by a method known per se.

Examples of the above ureas include urea, thiourea, ethylene urea and the like, and examples of the melamine cocondensation component include benzoguanamine, formguanamine, acetoguanamine, phenylacetoguanamine, CT.
Examples thereof include guanamines such as U guanamine; and other amino compounds such as guanidine, dicyanamide, and paratoluene sulfonamide.

The amount of the urea and / or melamine cocondensation component used is up to 0.7 mol per 1 mol of melamine, preferably in the range of the amount used, and the urea and / or melamine cocondensation component It is preferable to use it in a range where the weight used does not exceed the weight used for melamine. When the amount of the urea and / or melamine co-condensation component exceeds 0.7 mol per 1 mol of melamine, the light resistance, weather resistance, heat resistance and stain resistance of the resulting melamine-based molded article tend to decrease. Not preferable.

Examples of aldehyde components other than formaldehyde include aliphatic aldehydes such as acetaldehyde, propionaldehyde and butyraldehyde; aromatic aldehydes such as benzaldehyde; furfural; other components for melamine, urea and melamine cocondensation. Examples thereof include aldehyde compounds other than formaldehyde that can be attached / condensed with.

The amount of the aldehyde component other than the above-mentioned formaldehyde used is up to 0.5 mol per mol of formaldehyde, and preferably, the amount of the aldehyde component used is less than the amount of formaldehyde used while satisfying the range of the used amount. It is better to use it within the range. If the amount of aldehyde components other than the formaldehyde exceeds 0.5 mol per mol of formaldehyde, the melamine,
The reactivity of addition / condensation with the urea and the melamine co-condensation component tends to decrease, which is not preferable, and the curing rate of the resulting melamine-based resin molding composition may decrease, which is not preferable.

In the present invention, the term "formaldehyde" includes compounds such as paraformaldehyde that substantially act as formaldehyde in the addition / condensation reaction with the melamine, ureas and melamine cocondensation components. It is a name.

The melamine / formaldehyde resin (a) is preferably a melamine / formaldehyde resin or a melamine / urea / formaldehyde co-condensation resin which may contain up to 0.7 mol of urea per 1 mol of melamine.

Next, as the mixed resin of the constituent elements (I) and (b), for the melamine / formaldehyde resin of (a), (a) the urea alone or the urea, and melamine and the urea In addition to formaldehyde alone or a mixture of one or more aldehyde components other than the above-mentioned other aldehyde components, is added to a mixture with a urea co-condensation component consisting of other amino components by a method known per se. It is a specific mixed resin obtained by blending a urea / formaldehyde-based resin obtained by a condensation reaction, (b) the above ureas, and (a) and (b) or both of them.

Examples of the urea co-condensation component include the same compounds as the melamine co-condensation component.

The amount of the urea co-condensation component used in the urea / formaldehyde resin of the above (a) is up to 0.5 mol per 1 mol of urea, and preferably, the range of the amount used is satisfied and at the same time the urea co-condensation component is used. It is advisable to use the components in a weight range not exceeding the urea weight. If the amount of the urea co-condensation component exceeds 0.5 mol per 1 mol of urea, the light resistance and the like of the obtained melamine-based molded article tend to be deteriorated, which is not preferable.

Further, as the aldehyde component other than formaldehyde in the above (a) resin, the same aliphatic aldehydes as described in the case of the above (a) melamine / formaldehyde resin; aromatic aldehydes; furfural;
Other examples include aldehyde compounds other than formaldehyde capable of addition-condensation with the above-mentioned urea and urea co-condensation components.

The amount of the aldehyde component other than the above-mentioned formaldehyde used is up to 0.5 mol per mol of formaldehyde, and preferably, the amount of the aldehyde component used is less than the amount of formaldehyde used while satisfying the range of the used amount. It is better to use it within the range. When the amount of the aldehyde component other than the formaldehyde exceeds 0.5 mol with respect to 1 mol of formaldehyde, the reactivity of addition / condensation with the urea and the urea cocondensation component tends to decrease, and the melamine obtained. The curing speed of the resin-based molding material may also decrease, which is not preferable. In addition, the above
(b) In the mixed resin, formaldehyde also includes compounds that substantially act as formaldehyde during the addition / condensation reaction with the urea or melamine and other amino components other than urea, such as paraformaldehyde. Is the name of

As the above-mentioned (b) ureas, one or more of the above-mentioned ureas may be used alone or as a mixture, and the moldability such as disc flow characteristics and minimum shaping pressure characteristics, and the molded articles obtained are obtained. It is preferable to use urea alone from the viewpoint of the light resistance of the above.

Examples of the mixed resin (b) include urea formaldehyde, which is an addition / condensation product of urea alone and formaldehyde alone, to melamine / formaldehyde resin, which is an addition / condensation product of melamine alone and formaldehyde alone in (a). A mixed resin prepared by blending resins and a mixture prepared by blending urea with the melamine / formaldehyde resin (a) are preferred.

Further, the amount of urea in the mixed resin is up to 0.7 mol per 1 mol of melamine, and the amount of urea is 1 mol of melamine.
If the amount exceeds 0.7 mol per mol, the heat resistance and stain resistance of a molded article produced using the obtained melamine-based resin molding material tend to deteriorate, which is not preferable.

Further, by blending the melamine / formaldehyde resin of (a) and the melamine / formaldehyde resin of (b) with (a) urea / formaldehyde resin and (b) urea, or both. Mixed resin,
In the melamine-based resin selected from the group consisting of, the total amount of all aldehyde components including formaldehyde is preferably 1 or more and 2 or less with respect to 1 mol of total amino components including melamine and ureas.

If the above molar ratio exceeds 2, the molded product tends to be brittle, and properties such as crack resistance may deteriorate. On the other hand, when the molar ratio is less than 1, the curing rate of the obtained melamine-based resin molding material tends to be low, and the "bleeding" state of the melamine-based molding may be deteriorated.

The above (1) melamine-based resin includes (a) melamine in resin /
A formaldehyde resin, a melamine / urea / formaldehyde co-condensation resin and a resin (b) in which the melamine / formaldehyde resin is blended with urea / formaldehyde resin or urea are preferable.

As the polyoxyalkylene compound of the constituent requirement (II), for example, POE such as polyoxyethylene (hereinafter sometimes abbreviated as POE) / monolaurate, POE / monooleate, POE / distearate and the like, and a carbon number of 8 to 20 Mono- or diesters with saturated or unsaturated higher fatty acids; POE
・ POE such as monolauryl ether, POE ・ monooleyl ether, POE ・ distearyl ether and carbon number 8-20
Mono or diethers with saturated or unsaturated higher alcohols; POE / octylphenol ether, POE / noniphenol ether and other POE ethers with phenols substituted with saturated or unsaturated alkyl groups having 8 to 20 carbon atoms; POE-castor oil fatty acid ether and other POE and saturated or unsaturated higher oxy fatty acid having 8 to 20 carbon atoms and one or more hydroxyl groups; POE-sorbitan-
Monolaurate, POE, sorbitan, monooleate, P
Ethers of OE / sorbitan / tristearate and other POEs with sorbitan mono-, di- or tri-higher fatty acid (C8-20 saturated or unsaturated) esters; POE / glycerin / monooleate and other POEs and glycerin mono-higher Ether with fatty acid (C8-20, saturated or unsaturated) ester; POE / polyoxypropylene or less (sometimes abbreviated as POP) / POE / POP / block copolymer such as cetyl ether and C8-20 Ethers with saturated or unsaturated higher alcohols; and the like. The above polyoxyalkylene compounds may be used alone or in combination.

Among the polyoxyalkylene-based compounds, the disc flow characteristics of the melamine-based resin molding material obtained by blending with the melamine-based resin of the constituent requirements (I) of the present invention, such as the minimum pressurizing pressure characteristics and releasability. From the viewpoint, a monoester of POE and a saturated or unsaturated higher fat having 8 to 20 carbon atoms is preferable. Also, the above PO
Among the monoesters of E and saturated or unsaturated higher fatty acids having 8 to 20 carbon atoms, POE has an average molecular weight of about 100 to about 1000.
Those having about 150 to about 500 are particularly preferable. Further, POE having an average molecular weight of POE of about 150 to about 500.
Most preferred is monooleate.

The compounding amount of the polyoxyalkylene compound of the constituent requirement (II) to the melamine resin of the constituent requirement (I) of the present invention is 0.4 to 3 parts by weight based on 100 parts by weight of the melamine resin. If the amount is more than 3 parts by weight, the bleed-out prevention property tends to be unsatisfactory, and if it is less than 0.4 parts by weight, the substantial effect is difficult to appear, which is not preferable.

The melamine-based resin molding material of the present invention usually contains a pulp commonly used in this technical field, in addition to the melamine-based resin of the constituent requirements (I) and the polyoxyalkylene-based compound of the constituent requirements (II). It is normal. The pulp is usually a raw material for paper, chemical fibers, cellulose-based plastics, etc., and refers to a chain polymer derived from a cellulose raw material and containing α-cellulose as a main component, and generally industrially wood and linters. A fiber made from a cellulose raw material treated with is used.

The blending amount of the pulp is about 20 to about 80 parts by weight with respect to 100 parts by weight of the melamine resin from the viewpoint of molding suitability such as disc flow characteristics and minimum shaping pressure characteristics, and mechanical strength of the molded product. It is usually blended in the amount used.

If the amount of pulp is too small (less than 20% by weight), the bending strength tends to decrease. If the amount exceeds 80 parts by weight and the amount is too large, the moldability may decrease. Therefore, it is preferable to use within the above-mentioned exemplified amount range. Suitably, the amount used is about 30 to about 60 parts by weight with respect to 100 parts by weight of the melamine resin.

Further, the melamine-based resin molding material of the present invention may contain other appropriate additives depending on the desired purpose, as long as the performance of the composition is not impaired. Examples of such additives include, for example, rock wool, glass fiber, synthetic fiber, calcium carbonate, talc, clay,
Organic or inorganic fillers such as silica; for example, phthalic anhydride, p-toluenesulfonic acid, dimethyl oxalate, dibenzyl oxalate, dimethyl phthalate, benzoyl peroxide, epichlorohydrin, triethanolamine p-toluenesulphonate. , 2-aminoethysulfonic acid, dimethylaniline sulfonic acid hydrochloride, melamine oxalate, ammonium chloride, ammonium phosphate, trimethyl phosphate, acetamide, oxamide, etc. curing catalysts; for example, titanium oxide, zinc oxide, zinc sulfide red iron oxide , Navy blue, barium sulfate, iron black, ultramarine, carbon black, lithopone, titanium yellow, cobalt blue, hansa yellow, benzidine yellow, lake red, aniline black, dioxazine violet, quinacridon red, quinacrid. Nbaioretsuto, such inorganic or organic pigments such as naphthol yellow, phthalocyanine blue, phthalocyanine green; for example, zinc stearate, zinc myristate, aluminum stearate, calcium stearate, butyl cetearyl A, stearyl stearate, dioctyl phthalate,
Lubricants such as dibutyl phthalate, stearic acid amide, ε-caprolactam, oleic acid amide, linoleic acid amide, stearyl alcohol, polyoxyethylene stearate, glycerin, polyethylene glycol monooleate; lubricants and plasticizers are exemplified. You can

The melamine-based resin molding material according to the present invention can be suitably prepared, for example, by the so-called wet method as described below.

For example, with respect to 1 mol of so-called melamine crystal powder which can be produced by a method known per se such as a carbide method or a urea method, formalin aqueous solution having a concentration of 36% and / or paraformaldehyde in a form of about 1 to about formaldehyde is used.
At a reaction molar ratio of about 2 mol, in an aqueous medium, a pH of about 7-
Melamine resin liquid obtained by reacting at about 9; for example, pulp (μ-cellulose) is added to a melamine resin liquid having a resin solid content concentration of about 40 to about 60% by weight, and the solid content of the melamine resin liquid is 100 parts by weight. For example, POE monooleate having an average molecular weight of about 150 to about 500 in the POE portion is added in an amount of 0.4 to 3 parts by weight based on 100 parts by weight of the solid content of the melamine resin solution. It is blended so as to be parts by weight, kneaded, and dried at a temperature of, for example, about 70 ° to about 100 ° C to obtain, for example, a so-called popcorn having a diameter of about 3 cm to about 0.5 cm, which is finely processed. It can be obtained in the form of the resulting popcorn milled product.

The above-mentioned pulverization treatment can be performed by means such as an impact hammer mill, a ball mill, a vibration mill and a tower mill. If desired, for example, after preliminarily pulverizing with an impact hammer mill, further finely pulverizing with a means such as a ball mill, a vibration mill or a tower mill. Commercially available pulp and melamine resin-containing molding powder can be used, and if desired, the commercial molding powder can be further pulverized and used.

As the kneading means at the time of forming the popcorn, a kneader, a cokneader, or the like can be used, and as the drying means,
Hot air drying, band dryer drying, fluidized drying, etc. can be illustrated.

The form of the melamine-based resin molding material of the present invention can be appropriately selected and is not limited to the finely powdered powder.
It does not matter whether it is in a granular form or in any form as long as it has a particle size that can be used for molding.

The melamine-based resin molding material of the present invention obtained as described above is once heated and kneaded with an extruder, a heating roll machine or the like, and the obtained preliminary composition for molding is re-ground to be suitable for handling at the time of molding or the like. It is preferably used as a melamine-based resin molding material having a range of particle sizes.

At this time, in the above heating and kneading, an extruder can be appropriately selected without any limitation, and, for example,
A single screw extruder, a twin screw extruder, etc. can be illustrated.
The compression ratio and the temperature can be appropriately selected, and the compression ratio of 1.1 to 3 and the temperature conditions such as about 50 to about 130 ° C. can be exemplified. The extrusion end of the extruder may be of any type such as an open type or a screen die type, and the twin-screw extruder may be of the same-direction twin-screw type or different-direction twin-screw type. Further, the type of heating roll machine can be appropriately selected.

Re-grinding of the preliminary molding composition obtained by heat kneading can be carried out by using any re-grinding means capable of forming a re-ground product. If desired, sieving means can be used in combination. Examples of a crusher used for such re-crushing include an impact crusher, a hammer mill, an atomizer, a pin mill, a roll mill, a palpelizer and the like.

The re-ground product thus obtained has a particle size from the viewpoint of ease of handling, especially at the time of molding, etc., preferably a JIS sieve of 10 mesh sieve passing and 100 mesh sieve not passing, 80 parts by weight or more, More preferably, it is 85% by weight or more. Further, it is preferable that the condition of heating and kneading at 80 to 120 ° C. for 10 to 30 seconds exhibits excellent performance as a melamine-based resin molding material. The melamine resin molding material also exhibits excellent automatic metering suitability.

The melamine-based resin molding material of the present invention can be molded into a desired molded product by utilizing known means such as compression molding, transfer molding, injection molding and the like.
As described above, the melamine-based resin molding material of the present invention has a good balance of improving effects such as excellent moldability, bleed-out prevention property, and mold releasability. In multi-stage compression molding such as molding, pattern molding with decorative foil, surface coating molding, etc., the molding cycle can be remarkably shortened without any trouble of molding failure, which is useful for improving productivity.

For example, in the case of patterned molding by three-stage compression molding, after the initial pressure operation and the subsequent degassing operation, the first stage molding is not performed until the decorative fooil can be placed on the first stage molded product. After placing the oil, the mold is closed and the second stage molding is performed, then the mold is opened again and the surface coating glaze is supplied, and the mold is closed and the third stage molding is performed for the final molding. In such a three-stage compression molding, which is usually used as a product, when a conventional melamine-based resin molding material is used, the total pressing time is about 45 to 90 seconds and the molding cycle is about 180 to 220 seconds. Is. However, the melamine-based resin molding material of the present invention has excellent moldability as described above,
Since it has a good balance of mold releasability, etc., the initial pressure operation can be practically omitted, and the first stage molding can be performed. After the first stage molding, the mold is opened and degassing and fooil placement are performed together. Since it can be carried out and the holding time of the first stage molding pressure can be greatly shortened, the total pressurizing time is about 25 to 50 seconds, and the molding cycle is about 125 to 165 seconds, which is industrially remarkable and advantageous. Three-stage compression molding can be performed.

Furthermore, there is no risk of a surface step between the part covered with foyle and the part not covered with the molded product, a molded product with excellent uniformity of the glaze layer thickness is obtained, and the risk of over-curing is eliminated. Such advantages can be achieved.

[Examples and test method]

Hereinafter, several embodiments of the present invention will be described in more detail with reference to examples together with comparative examples.

The test methods and evaluations of the disc flow characteristics, the minimum applied pressure characteristics, the bleed-out prevention property, the releasability and the heat resistance are as follows.

(1) Disc flow characteristic test Using a disc test die shown in JIS.K6911 section 5.3.2, a sample 5g was kept at a die temperature of 150 ± 3 ° C. A sample is put into a conical shape using a metal cylinder of 50 mm and a height of about 10 mm, and compression molding is performed within 15 seconds under a load of 2000 kgf and a pressing time of 2 minutes.

Measure the major and minor diameters of the glossy part of the molded disc with a dimension measuring instrument.
Measure up to 1 mm, calculate the average value, and extend the sample (mm)
And

(2) Using the moldability test mold shown in Section 5.4 of JIS.K6911, the test of the minimum molding pressure characteristics,
Obtain the minimum mold pressure under conditions of mold temperature of 150 ℃ / 150 ℃, mold clamping time of 15 seconds, no preheating, and no degassing. The minimum imprinting pressure is the lowest pressure that does not cause scratches or cracks on the molded product, especially at the edges, and is calculated by changing the pressure in units of 5 kg / cm ² and repeating molding several times.

(3) Bleed-out prevention property A test piece with dimensions 70 x 60 x 3 mm is used at a mold temperature of 165 ° C / 165
Mold under the conditions of ℃, molding pressure of 200 kg / cm ² and curing time of 90 seconds, take out the molded product, remove the upper mold, and measure the specular gloss of the surface. The glossiness is measured according to JIS Z8741. The bleeding prevention property is evaluated by using the percentage of the specular gloss after the material is formed with respect to the specular gloss of the well-cleaned upper metal mold surface.

(4) Releasability test A 9-inch flat plate with a wall thickness of about 3 mm was charged with a melamine-based resin molding material in a mold at a mold temperature of 160 ° C / 150 ° C, then the mold was closed, and the molding pressure was 100 kg / cm. Pressurize for a certain time after reaching ² . When the semi-cured molded product is not detached from the upper mold when the mold is opened and a part of the molded product adheres to the upper and lower parts, it is evaluated that the mold has not been released. As for the mold releasability, the pressing time is shortened in units of 1 second, and the minimum time that the semi-cured molded product of the melamine-based resin molding material does not separate into the upper and lower molds and remains in the lower mold is obtained.

(5) Heat resistance test Performed in accordance with JIS.K6911, Section 5.23, “Appearance after heating” test.

Melamine resin molding material, gold temperature 160 ℃ / 160 ℃, molding time 3 minutes, diameter 50 ± 1mm without preheating, thickness 3 ±
Mold a 0.2 mm disc. The test piece thus obtained is hung near a thermometer in a constant temperature bath kept at a constant temperature, taken out after 2 hours, and examined for any remarkable change in appearance such as cracks or blister. The above test is carried out at different temperatures, and the maximum temperature in the range where no significant change in appearance occurs is taken as the value of heat resistance.

Example 1 Melamine (Oilized Melamine Co., Ltd .; oiled melamine) 1260
g (10 mol), 1379 g (17 mol) of 37% aqueous formalin solution and 900 g of water were placed in a flask equipped with a reflux condenser, and F /
The mixture was heated and reacted at 90 ° C. with stirring under the condition of M = 1.7. When the cloud point of the melamine resin liquid reached 60 ° C., 0.8 g of NaOH was added and the mixture was cooled to obtain a melamine resin initial condensate. The cloud point used as a guide for the end of the reaction is the temperature at which cloudiness occurs when 5 ml of resin solution is sampled and 45 ml of hot water at about 80 ° C. is added and stirred and cooled.

The melamine resin initial condensate thus obtained (solid content of about 50
% Of pulp) 600 g of pulp (about 43 parts by weight relative to 100 parts by weight of solid content of melamine resin), and POE monooleate with an average molecular weight of about 200 () about 7 g of POE monooleate (solid content of melamine resin) After adding 0.5 part by weight to 100 parts by weight and kneading with a kneader, the kneaded product was dried with a hot air dryer at 90 ° C. for 90 minutes to obtain popcorn.

To this popcorn 500g titanium oxide 5g, phthalic anhydride
0.5 g of zinc stearate and 2.5 g of zinc stearate were added and pulverized with a pot mill for 8 hours to obtain a powder of a melamine-based resin molding material.

The powder of the above molding material was then made into a cold roll compression molded product by a cold roll compressor. Cold roll compression has a diameter of 25
Use a roll with a width of 0 mm and a width of 200 mm,
A cold roll compression molded product was obtained under the conditions of a roll speed of 20 rpm, a roll pressure pump pressure of 150 kg / cm ² , and a roll clearance of 0.5 mm at 300 kg / hr.

After crushing the cold roll compression molded product,
It was crushed using a 2 mmφ impact crusher to obtain a melamine resin molding material.

Using the above composition, a physical property test was conducted according to the test methods (1) to (5). The test results are shown in Table 1. From these results, the melamine-based resin molding material of Example 1 has appropriate disc flow characteristics and appropriate minimum impression pressure characteristics, and also has excellent bleed-out prevention properties and excellent mold release. He had both sex. The molded product obtained from the above composition was also excellent in heat resistance.

Examples 2 to 4 and Comparative Examples 1 and 2 In Example 1, a melamine resin molding material was prepared by changing only the addition amount of POE monooleate of about 200.
Similarly, physical property tests were conducted. Table 1 shows the components and test results of the obtained melamine-based resin molding material.

Example 5 In Example 1, POE monooleate of about 400 was used, and the amount of the POE monooleate added was 14 g (1.0 part by weight based on 100 parts by weight of the solid content of the melamine resin). A resin molding material was prepared and a physical property test was conducted in the same manner. Table 1 shows the components and test results of the obtained melamine-based resin molding material.

Comparative Examples 3 to 5 In Example 1, = about 200 POE monooleate 7 g
Instead of using (0.5 parts by weight based on 100 parts by weight of the solid content of the melamine-based resin), polyethylene glycol (about PEG) of about 400 or about 6000 or propylene glycol of about 1000 (below) may be used. , PPG
Of the melamine-based resin is used in an amount of 14 g (1 part by weight based on 100 parts by weight of the solid content of the melamine-based resin).
Similarly, physical property tests were conducted. Table 1 shows the components and test results of the obtained melamine-based resin molding material.

Reference Example 1 Preparation of Urea / Formaldehyde Resin 600 g (10 mol) of urea (manufactured by Nissan Chemical Industries, Ltd.) and 1176 g (14.5 mol) of 37% by weight concentration formalin aqueous solution were put in a separable flask, and F / U = 1.45. Under the conditions, after reacting at 60 ° C for 100 minutes, 1.4 ml of 10% NH ₄ Cl aqueous solution is added, and after stirring for 10 minutes, the water bath temperature is lowered to 50 ° C and the reaction is further stirred for 20 minutes.

To 1000 g of the thus obtained urea resin liquid (solid content: about 58% by weight), 184 g of pulp (about 32 parts by weight based on 100 parts by weight of solid content of urea resin) was added and kneaded with a kneader. It was dried with a hot air dryer for 120 minutes to obtain a popcorn.

Example 6 In Example 1 = 20 g of POE monooleate of about 200
125 g of the popcorn obtained in Reference Example 1 was added to 375 g of the popcorn obtained in the same manner except that the titanium oxide was used.
Add 5 g, phthalic anhydride 0.5 g, zinc stearate 2 g,
It was pulverized for 8 hours with a pot mill to obtain a powder of a melamine-based resin molding material.

The powder of the above molding material was then granulated in the same manner as in Example 1. Using the melamine resin molding material thus obtained, a physical property test was conducted in the same manner as in Example 1. The test results are shown in Table 1.

Example 7 A melamine resin molding material was prepared in the same manner as in Example 6 except that POE monooleate of about 400 was used.
Similarly, physical property tests were conducted.

The components of the resin composition and the test results are shown in Table 1.

Example 8 Melamine (Oilized Melamine Co., Ltd .: Oiled melamine) 1260
g (10 mol), urea (manufactured by Nissan Chemical Industries, Ltd.) 300 g (5
Mol), 1950 g of 37% by weight aqueous formalin solution (about 24
Mol) and 643 g of water in a separable flask and at 80 ° C.
For 60 minutes, 1N-NaOH (about 20 ml) was added, and the mixture was cooled to obtain a melamine-based resin condensate having a solid content of about 55% by weight.

To 1000 g of the resin condensate thus obtained, 237 g of pulp (about 43 parts by weight based on 100 parts by weight of melamine-based resin solids), and further = about 200 g of POE monooleate (1 part by weight based on melamine-based resin solids). Part) and kneaded with a kneader, and the mixture was dried at 90 ° C. for 90 minutes with a hot air dryer to obtain popcorn.

To this popcorn 500g titanium oxide 5g, phthalic anhydride
0.5 g of zinc stearate and 2.5 g of zinc stearate were added and pulverized with a pot mill for 8 hours to obtain a powder of a melamine-based resin molding material.

The above molding material powder was then granulated in the same manner as in Example 1. Using the melamine-based resin molding material thus obtained, a physical property test was conducted in the same manner as in Example 1. The test results are shown in Table 1.

Example 9 A melamine-based resin molding material was prepared in the same manner as in Example 6 except that 400 g of the popcorn obtained in Example 3 and 100 g of the popcorn obtained in Reference Example 1 were used. It was The test results are shown in Table 1.

Example 10 A melamine-based resin molding material was prepared in the same manner as in Example 6 except that 450 g of the popcorn obtained in Example 3 and 50 g of the popcorn obtained in Reference Example 1 were used. Natsuta. The test results are shown in Table 1.

Examples 11 and 12 and Comparative Example 6 A melamine-based resin molding material was prepared in the same manner as in Example 6 except that the popcorn obtained in Example 3 and urea were used at different compounding ratios, and the physical properties were similarly tested. Was done. The components and test results of the obtained melamine-based resin molding material
Shown in the table.

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display area B29K 61:20 4F

Claims (3)

[Claims] 1. (I) The following (a) and (b), (a) melamine / formaldehyde resin, and (b) (a) melamine / formaldehyde resin, and (b) urea / formaldehyde resin. And / or (b) 100 parts by weight of a melamine-based resin selected from the group consisting of mixed resins consisting of ureas, (II) a polyoxyalkylene group, and a saturated or unsaturated C8-20 A polyoxyalkylene compound containing a group of a higher aliphatic compound in the same molecule.
A melamine-based resin molding material characterized by being mixed with 4 to 3 parts by weight. 2. The melamine according to claim 1, wherein the polyoxyalkylene compound is an ester of polyoxyethylene and a saturated or unsaturated higher fatty acid having 8 to 20 carbon atoms. Resin molding materials. 3. The melamine-based compound according to claim 1, wherein the polyoxyalkylene-based compound is polyoxyethylene monooleate having an average molecular weight of the polyoxyethylene portion of about 150 to about 500. Resin molding material.