CN104093507B - Mould using for organic binder, use its molding sand composition obtained and casting mold - Google Patents

Abstract

The present invention provides the generation of a kind of stink when making molds be greatly reduced, stimulation, cigarette etc., it is capable of the raising of the operability of gained casting mold, and advantageously improve the mould using for organic binder of anti-shelling, and also provide the RCS using this organic binder bond to obtain, and this RCS is used to carry out the casting mold with excellent specific property that moulding obtains.Usage rate is calculated as the linear phenol-aldehyde resin (A) of A:B=95:5～5:95 and fusible type phenolic resin (B) using quality criteria and at least Arrhenius alkali of curing accelerator and/or brnsted base as the curing reaction that can promote these phenolic resin combine, constitute mould using for organic binder.

Description

Mould using for organic binder, use its molding sand composition obtained and casting mold

Technical field

The present invention relates to mould using for organic binder, the molding sand composition using it to obtain and casting Type, particularly to achieving the improvement of working environment in sand casting, and can advantageously make Make the phenolic resin system mould using for organic binder of the casting mold with excellent specific property, use it to obtain Molding sand composition and use this molding sand composition moulding and the casting mold that formed.

Background technology

All the time, in using shell moulded casting as the sand casting represented, generally use following Shell casting mold, i.e. by fire resistance particle (molding sand) and phenolic resin (binding agent) and according to Need the firming agent such as the hexamethylenetetramine used further to carry out mixing, use the resin obtained Precoated sand (hreinafter referred to as " RCS "), carries out hot briquetting to it, is consequently formed tool There is the shell casting mold of intended shape.

But, when carrying out the manufacture of this RCS, if using hexamethylenetetramine conduct Firming agent, then when making molds when being heating and curing, except because use phenolic resin and produce Outside formaldehyde, also as the decomposition of hexamethylenetetramine and create ammonia, and these gas become For the reason of stench, also become the factor causing working environment to deteriorate, therefore should Reduce this addition as the hexamethylenetetramine of firming agent, and have been proposed for multiple having Close the countermeasure of the interpolation etc. of the curing accelerators modified, various of phenolic resin.

Such as, in patent documentation 1, it is proposed that alkali metal will be contained in linear phenol-aldehyde resin Salt of weak acid or alkali metal hydroxide and the phenol resin composition that formed and hexamethylenetetramine Together carry out mixing with fire resistance bulk material, thus manufacture shell mould casting mold RCS, thus may be used Know, it is possible to reduce the usage amount of hexamethylenetetramine, decrease ammonia generation amount, there is energy simultaneously The curable of enough making molds, and the effect that formative nature is also excellent can be played.But, for The intensity of the casting mold using this RCS to obtain is improved to the abundant degree in the most actually used, Need more hexamethylenetetramine usage amount, therefore, stink and the consequent thorn such as ammonia The problem swashed still exists.

Additionally, propose in patent documentation 2, in order to produce when obtaining and prevent from pouring into a mould in casting mold The RCS in crack, use linear phenol-aldehyde resin and/or fusible type phenolic resin as phenolic resin, And use Polyethylene Glycol, and be coated to casting mold with fire-resistant with these phenolic resin and Polyethylene Glycol Property shot-like particle, can be the use of and the conventional the most substantial amounts of hexa-methylene four as firming agent Amine, so ammonia, formaldehyde is gas generated many, there are the stink because these gas causes, The problem such as stimulate, be fuming, and in the hollow using this RCS to carry out overturning sediment outflow moulding In casting mold, the splitting when upset or anti-shelling (the anti peel-back that comes off Property) aspect there is also problem, and exist insertion defect when easily producing casting, The problems such as gas defects.

And then, Patent Document 3 discloses following methods: will by fusible type phenolic resin and The phenolic resin system binding agent that linear phenol-aldehyde resin is formed with by selected from tripolycyanamide, carbamide, double The reactive curing accelerator that the amine compound of cyanamide is formed is used along, coating fire resistance bone The surface of material, the method obtaining RCS, but use the casting mold that this RCS obtains, its behaviour The property made is poor, easily produce when the demoulding, the carrying of casting mold fracture, the problem such as slight crack, Er Qie Anti-shelling aspect is the most insufficient.

Additionally, Patent Document 4 discloses following methods: linear phenol-aldehyde resin quilt will be used Cover fire resistance aggregate that surface formed further with fusible type Phenolic resin emulsion or suspension Mixing, the surface of this fire resistance aggregate is implemented further resin-coated, thus manufacture and have Low odor, high intensity, the method for shell mould casting mold casting RCS of difficult adhesive.That is, because of This is fusible type phenolic resin the can serve as firming agent of linear phenol-aldehyde resin, but only with this two When kind of phenolic resin is coated to the surface of fire resistance aggregate, use the casting mold that this RCS obtains Operability is poor, and anti-shelling is the poorest, there is bigger problem in actual use.Additionally, Although also disclose that the fusible type Phenolic resin emulsion coating further for fire resistance aggregate or Containing the organonitrogen compound such as carbamide, tripolycyanamide or hexamethylenetetramine in suspension, but Even if containing this organonitrogen compound, it is also difficult to fully realize aforesaid operations, hollow casting mold The raising of anti-shelling during moulding, if additionally, increasing the usage amount of hexamethylenetetramine, then Also can produce the problem such as stink, stimulation.

Patent documentation 1: Japanese Unexamined Patent Publication 2003-170244 publication

Patent documentation 2: Japanese Laid-Open Patent Publication 58-119433 publication

Patent documentation 3: No. 4369653 publications of Japanese Patent No.

Patent documentation 4: Japanese Unexamined Patent Publication 11-244991 publication

Summary of the invention

Here, the present invention completes with above-mentioned situation as background, and it solves problem and is There is provided a kind of generation of stink, stimulation, cigarette etc. when making molds is greatly reduced, it is possible to realize The raising of the operability of gained casting mold, and advantageously improve the casting mold of anti-shelling with organic viscous Knot agent, and also the RCS using this organic binder bond to obtain is provided, and use this RCS Carry out the casting mold with excellent specific property that moulding obtains.

In order to solve such problem, the present invention can suitably use the various sides being exemplified below Formula is implemented, and, it would however also be possible to employ the combination in any of various modes set forth below.Need Illustrate, the mode of the present invention or technical characteristic, not any by content set forth below Limit, and be interpreted as overall record based on description recognizing.

(1) a kind of mould using for organic binder, it is characterised in that by linear phenol-aldehyde resin, The curing accelerator of fusible type phenolic resin and the curing reaction that these phenolic resin can be promoted Combination is formed, and this linear phenol-aldehyde resin (A) and this fusible type phenolic resin (B) Usage rate is calculated as A:B=95:5～5:95 with quality criteria, meanwhile, as this solidification Accelerator, at least contains Arrhenius alkali and/or brnsted base.

(2) mould using for organic binder described in (1) in the manner described above, it is characterised in that As described Arrhenius alkali, the pH using 0.1mol/l aqueous solution is 10～Ah Lei of 14 At least one of Ni Wusi alkali.

(3) mould using for organic binder described in (2) in the manner described above, it is characterised in that Described Arrhenius alkali is selected from sodium hydroxide, Lithium hydrate, calcium hydroxide and potassium hydroxide.

(4) the casting mold organic adhesive according to any one of (1)～(3) in the manner described above Agent, it is characterised in that as described brnsted base, use the pH of 0.1mol/l aqueous solution It is at least one of alkali metal inorganic salt of 8～14.

(5) mould using for organic binder described in (4) in the manner described above, it is characterised in that Described alkali metal inorganic salt is selected from sodium carbonate, sodium bicarbonate, potassium carbonate, lithium carbonate, sulfurous acid Sodium, sodium aluminate and sodium stannate trihydrate.

(6) the casting mold organic adhesive according to any one of (1)～(5) in the manner described above Agent, it is characterised in that as described brnsted base, use the pH of 0.1mol/l aqueous solution It is at least one of alkaline metal organic salt of 2～7.5.

(7) mould using for organic binder described in (6) in the manner described above, it is characterised in that Described alkaline metal organic salt is selected from sodium alginate, sodium salicylate, sodium benzoate, 1-naphthols-5 -sodium sulfonate, p-phenolsulfonic acid's sodium and paratoluenesulfonic acid sodium salt.

(8) the casting mold organic adhesive according to any one of (1)～(7) in the manner described above Agent, wherein, relative to the total amount of described linear phenol-aldehyde resin Yu described fusible type phenolic resin 100 mass parts, described Arrhenius alkali and/or brnsted base the solidification formed promotes The total amount of agent is in the range of 0.2～15 mass parts.

(9) the casting mold organic adhesive according to any one of (1)～(8) in the manner described above Agent, it is characterised in that contain hexamethylenetetramine further.

(10) a kind of molding sand composition, it is characterised in that make in fashion described above (1)～(9) According to any one of mould using for organic binder, and by described mould using for organic binder and type Sand is mixing and is formed.

(11) molding sand composition described in (10) in the manner described above, wherein, relative to molding sand 100 mass parts, described mould using for organic binder mixes with the ratio of 0.2～10 mass parts Refining.

(12) molding sand composition described in (10) or (11) in the manner described above, wherein, institute State linear phenol-aldehyde resin to promote in described solidification with the resin compound of described fusible type phenolic resin Before entering agent mixing with described molding sand.

(13) in the manner described above the molding sand composition described in (10) or (11), wherein, joins The described linear phenol-aldehyde resin and the described fusible type phenolic resin that have closed described curing accelerator divide Not mixing with described molding sand.

(14) a kind of casting mold, it is characterised in that make in fashion described above in (10)～(13) Molding sand composition described in any one carries out moulding, and is heating and curing and is formed.

Invention effect

Be as noted previously, as the mould using for organic binder of the present invention be by linear phenol-aldehyde resin, Fusible type phenolic resin with as the Arrhenius alkali of curing accelerator and/or Bronsted Alkali combines and constitutes, and does not the most use substantial amounts of hexamethylenetetramine as solid Agent, therefore can avoid pyrolysis based on this firming agent etc. and produce ammonia, formaldehyde, thus The generation amount of the ammonia from whole binding agents, formaldehyde can be reduced as far as, effectively suppress The problem produced based on stink, stimulation etc., and can be advantageously carried out working environment Improve.

And, for the mould using for organic binder of this present invention, due to by line style phenol Urea formaldehyde, fusible type phenolic resin with as the Arrhenius alkali of curing accelerator and/or Blang Si Taide alkali combines, so using the tunicle on the RCS Sand surface that this binding agent formed Can more rapidly and efficiently be solidified, and can advantageously improve and be obtained by this RCS The operability of the casting mold arrived.Additionally, by the raising of this operability, can effectively suppress Or fractureing when carrying out the demoulding, carrying after stoping firm making molds etc., the generation of slight crack etc., And the reduction of disqualification rate, the raising of productivity ratio during casting mold casting can be advantageously carried out.

Further, for the mould using for organic binder of this present invention, by using Its RCS obtained carries out in the casting mold of moulding, can be effectively improved its anti-shelling, by This, can be readily formed the casting mold of uniform wall thickness, can maintain the intensity of casting mold simultaneously, Thus advantageously suppress or avoid insertion defect when casting, the generation of gas defects.

Detailed description of the invention

In the mould using for organic binder of the present invention, constitute its linear phenol-aldehyde resin and fusible Type phenolic resin is to make phenols anti-with aldehydes in the presence of acidic catalyst or base catalyst The solid, shaped answered and obtain or the condensation product (root of liquid (such as, varnish shape or emulsion etc.) Line style or fusible type is formed according to the kind of the catalyst used), and be the solidification in regulation In the presence of agent or curing catalysts or in the absence of carry out heating and showing heat cured phenol Urea formaldehyde.

The phenols that can serve as this phenolic resin starting material refers to the derivant of phenol and phenol, example As, in addition to phenol, it is also possible to enumerate cresol, xylenols, p-t-butyl phenol, nonyl Polyhydric phenols and their mixture such as the alkyl phenols such as phenol, resorcinol, Bisphenol F, bisphenol-A Deng known material, and can be used alone one therein or two or more combinations are made With.

Additionally, as aldehydes, such as, except as formalin form formalin with Outward, it is also possible to enumerate paraformaldehyde, trioxane, acetaldehyde, paraldehydum, propionic aldehyde etc., And then known aldehyde compound in addition can also be suitably used.And these aldehydes Being used alone or being used in combination of two or more all does not has any problem.

The phenolic resin that the linear phenol-aldehyde resin that can use in the present invention is formed as: use Above-mentioned phenols and aldehydes, as is well known, by acidic catalyst, such as, hydrochloric acid, sulfur The mineral acids such as acid, phosphoric acid, oxalic acid, p-methyl benzenesulfonic acid, benzenesulfonic acid, xylene monosulfonic acid etc. are organic Acid, and the acidic materials such as zinc oxide, zinc chloride, magnesium oxide, zinc acetate carry out condensation reaction And formed.It should be noted that at this moment, rub with coordinating of phenols (P) as aldehydes (F) Your ratio (F/P), can properly select according to the kind of the catalysts used etc., Preferably select in the range of 0.55～0.80.

On the other hand, fusible type phenolic resin is to use above-mentioned phenols and aldehydes, and the most same Ground carries out condensation reaction by known base catalyst and is formed.It should be noted that conduct Base catalyst, it is possible to use the alkali metal such as sodium hydroxide, calcium hydroxide or the hydrogen of alkaline-earth metal Oxide, the oxide of alkaline-earth metal, in addition to this it is possible to use dimethylamine, triethylamine, The amines such as butylamine, dimethyl benzylamine, naphthylenediamine, ammonia, hexamethylenetetramine and divalent gold The naphthenate (naphthenate) of genus, the hydroxide etc. of divalent metal.Additionally, this contracting In conjunction reaction, aldehydes can be according to the catalytic reaction used with the mol ratio (F/P) that coordinates of phenols The kind of agent etc. and properly select, and generally in the range of 1.1～4.0 select.

In the mould using for organic binder of the present invention, as its resin-bonded composition, together make With the linear phenol-aldehyde resin obtained as mentioned above and fusible type phenolic resin, fusible type phenolic aldehyde Resin serves the function of the firming agent as linear phenol-aldehyde resin, is used simultaneously as improving casting The composition of the characteristics such as type bending strength.Further, by these linear phenol-aldehyde resins (A) with can Molten type phenolic resin (B) used time, their usage rate is counted with quality criteria to be needed as A: B=95:5～5:95, it is therefore highly desirable that, advantageously with A:B=30:70～70: The usage rate of 30.

If it should be noted that the usage rate of this fusible type phenolic resin relative to line style The total amount of phenolic resin is more than 95 mass %, and the usage rate of therefore linear phenol-aldehyde resin Less than 5 mass %, then when being used in mixed way both phenolic resin, it is difficult to by them equably Mixing, and it is not used as the residual quantitative change of the fusible type phenolic resin of linear phenol-aldehyde resin firming agent Many, create the problem that the raising effect of the curing rate overall as binding agent is insufficient.This Outward, in contrast, if the use ratio of fusible type phenolic resin is less than 5 mass %, and line The usage rate of type phenolic resin, then cannot be by fusible type phenolic resin more than 95 mass % Making its linear phenol-aldehyde resin solidified become many, this remaining linear phenol-aldehyde resin is uncured and remains Get off, it is difficult to realize being fully cured of binding agent, it is thus possible to the intensity of casting mold can be caused to decline.

Additionally it is believed that due to the curing reaction of this linear phenol-aldehyde resin Yu fusible type phenolic resin Essentially dehydration condensation, so by being carried by Arrhenius alkali and/or brnsted base For OH^-, accept H⁺So that the phenyl ring activation of linear phenol-aldehyde resin, promote above-mentioned solidification The dehydration of reaction, its response speed accelerates.

Herein, the Arrhenius alkali that can serve as reaction promoter is can to give birth to when being dissolved in water Become hydroxyl ion (OH^-) compound, wherein, 0.1mol/l can be preferably used in the present invention The pH of aqueous solution is the Arrhenius alkali of 10～14.Think when this Arrhenius aqueous alkali When the pH of solution is 10～14, demonstrating strong basicity, it is by providing OH^-, so that The phenyl ring activation of linear phenol-aldehyde resin, accelerates fusible type phenolic resin solid with linear phenol-aldehyde resin Dehydration condensation during change.

Additionally, as this Arrhenius alkali, particularly preferably sodium hydroxide (pH=13.5), Lithium hydrate (pH=13.0), calcium hydroxide (pH=13.1), potassium hydroxide (pH=13.4) In any one, and can be used alone one therein or two or more combinations made With.It should be noted that the pH value in each compound unquote is the 0.1mol/l of each compound The pH value of aqueous solution.

And then, in the present invention, as curing accelerator, can be by above-mentioned Arrhenius alkali Used along with the brnsted base of regulation, or substituted Ah tiring out by the brnsted base specified Ni Wusi alkali uses, described brnsted base in other words for receive proton material, I.e. can accept H⁺Compound.

Further, when this brnsted base is alkali metal inorganic salt, it may be preferred to use it The pH of 0.1mol/l aqueous solution is the material of 8～14.When the alkali gold as brnsted base When the pH of the 0.1mol/l aqueous solution belonging to inorganic salt is 8～14, hydrolysis generates OH^-Ion, Thus it is believed that by the reaction mechanism identical with above-mentioned Arrhenius alkali, accelerate line Dehydration condensation when type phenolic resin and fusible type phenolic resin curing.

Additionally, as the alkali metal inorganic salt of this brnsted base, preferably sodium carbonate (pH =11.6), sodium bicarbonate (pH=8.6), potassium carbonate (pH=11.5), lithium carbonate (pH =11.5), sodium sulfite (pH=9.3), sodium aluminate (pH=11.4), sodium stannate three water Any one in compound (pH=11.8), and can be used alone one therein or incite somebody to action It is used in combination.It should be noted that the pH value in each compound unquote is each The pH value of the 0.1mol/l aqueous solution of compound.

Additionally, when brnsted base is alkaline metal organic salt, it can be advantageous to use it The pH of 0.1mol/l aqueous solution is the material of 2～7.5.Think when giving this pH value, By accepting the H of the phenyl ring of linear phenol-aldehyde resin⁺, accelerate linear phenol-aldehyde resin and fusible type Dehydration condensation during phenolic resin curing.

It should be noted that as the alkaline metal organic salt of this brnsted base, be preferably Sodium alginate (pH=7.3), sodium salicylate (pH=6.3), sodium benzoate (pH=7.3), 1-naphthol-5-sulfonic acid sodium (pH=3.3), p-phenolsulfonic acid's sodium (pH=5.8), to first Any one in benzene sulfonic acid sodium salt (pH=6.5), and can be used alone one therein or Person is used in combination of two or more.It should be noted that the pH value in each compound unquote It it is the pH value of the 0.1mol/l aqueous solution of each compound.

Additionally, Arrhenius alkali, the usage amount of brnsted base as above, entirely In the range of the usage amount of portion's curing accelerator.That is, relative to as two kinds of resin-bonded composition Total amount 100 mass parts of phenolic resin, Arrhenius alkali and/or the conjunction of brnsted base Metering is generally in 0.2～15 mass parts, preferably use in the range of 0.5～8 mass parts. It should be noted that its reason is, if the usage amount of this curing accelerator reduces, then It is difficult to give full play to its solidification facilitation effect, if additionally, its usage amount is too much, then casting mold Intensity can decline.

As described previously for the mould using for organic binder of the present invention, use linear phenol-aldehyde resin With fusible type phenolic resin as resin-bonded composition, and at least use accelerates these line styles The Arrhenius alkali of dehydration condensation when phenolic resin and fusible type phenolic resin curing And/or brnsted base is as curing accelerator, and in addition to these neccessary compositions, also may be used To add known various gradation compositions further.Especially as curing accelerator or solidification Agent, adds hexamethylenetetramine further, is effective in terms of the raising of RCS characteristic, If but its interpolation quantitative change is many, the most again creates the problems such as stink, therefore relative to conduct Total amount 100 mass parts of two kinds of phenolic resin of resin-bonded composition, generally with 10 mass Ratio below part, below preferably 8 mass parts, below more preferably 5 mass parts uses.

And, by the organic binder bond so constituting the present invention formed, by with known type Sand coordinates and is coated to its surface, defines for the casting molds such as shell mould casting mold are carried out moulding RCS.Wherein, as the usage amount of the organic binder bond for obtaining RCS, it is to consider wherein The kind of phenolic resin, the required mould strength etc. that use determine, therefore can not be without exception Ground limits, typically, relative to molding sand 100 mass parts, about 0.2～10 mass parts In the range of, preferably in 0.5～8 mass parts, more preferably in the range of 0.5～5 mass parts.

Additionally, for the molding sand carrying out being coated to this organic binder bond, can suitably select to make Using known material, its kind is not particularly limited in the present invention.Due to this molding sand Constitute the base material of casting mold, as long as so have and be resistant to the fire resistance of casting and be suitable for casting Type forms the inorganic refractory particle of the particle diameter of (moulding), it is possible to uses and is used for all the time Shell-molded inorganic particulate known to any one.Additionally, as this fire resistance particle, example As, in addition to generally using silica sand (salica sand), it is also possible to enumerate olivine sand (olivine Sand), zircon sand (zircon sand), chromium sand (chromite sand), aluminum oxide sand (alumina The special sand such as sand)；The stoves such as ferrochrome class slag (slag), ferronickel class slag, converter slag Slag class particle；Naigai Cerabeads (trade name, ITOCHU Ceratech Co., Ltd.) it The mullite class faux particles of class；Or the regeneration grain of reclaiming after they are cast Sons etc., they can be used alone or are used in combination of two or more.

It should be noted that when using the organic binder bond manufacturing objective RCS of the present invention, Its manufacture method is not particularly limited, and can use dry type thermal coating method, half thermal coating method, cold Any one methods known such as rubbing method, powder solvent method, but special recommendation in the present invention Use so-called dry type thermal coating method, i.e. at sand muller or high-speed mixing mill (speed Etc. mixer) in mixing roll, by preheated molding sand with constitute the resin-bonded of organic binder bond After composition (linear phenol-aldehyde resin+fusible type phenolic resin) is mixing, the solidification adding regulation promotees Enter agent aqueous solution, and make block content disintegrate be granular by air-supply cooling, add tristearin Acid calcium (lubricant).In addition, it will thus provide constitute the resin-bonded one-tenth of organic binder bond of the present invention The two kinds of phenolic resin, the curing accelerator that divide carry out can suitably selecting with molding sand mixing opportunity Select, in addition to the most mixing, it is also possible to be combined as carrying out mixing.

And then, the casting mold using the RCS obtained as mentioned above to specify shell mould casting mold etc. is carried out During moulding, being heating and curing of this RCS to be realized, and carry out target casting mold under heating Moulding, as this heating formative method, is not particularly limited, it can be advantageous to use in the past Any one method known.For example, it is possible to obtain casting mold as follows: by above-mentioned RCS By gravity fall mode or be blown into mode etc. be filled into have give target casting mold desired Shape space and in being heated to the shaping mould of 150 DEG C～300 DEG C so that it is solidification, then will The demoulding from above-mentioned shaping mould of casting mold after solidification.The casting mold obtained as mentioned above can be by favorably Ground gives the feature of above-mentioned excellence.

Embodiment

Hereinafter, provide several embodiments of the present invention, further illustrate the present invention, do not say and Any restriction of the content that the analogy present invention is not recorded by these embodiments.In addition, it will be appreciated that be In the present invention, in addition to following example, and then in addition to above-mentioned concrete description, also include Knowledge based on those skilled in the art are made without departing from the spirit and scope of the invention Various changes, revise, improvement etc..

It should be noted that " part " and " % " is as long as no being particularly limited in set forth below, Represent " mass parts " and " quality % " respectively.It addition, the various characteristics of the following RCS manufactured are pressed It is measured according to following test method.

-the manufacture example of linear phenol-aldehyde resin-

Put in the reaction vessel possessing thermometer, agitating device and condenser 940 parts of phenol, 428 part of 47% formalin and 2.8 parts of oxalic acid.It should be noted that phenol and formalin Cooperation mol ratio (F/P) be 0.67.Then, reaction vessel is slowly heated up, arrive After reaching reflux temperature, carry out back flow reaction 90 minutes, be further heated to reacting liquid temperature and reach To 170 DEG C, concentrating under reduced pressure, thus obtain linear phenol-aldehyde resin.

-the manufacture example of fusible type phenolic resin-

Put in the reaction vessel possessing thermometer, agitating device and condenser 680 parts of phenol, After 535 part of 47% formalin and 101 parts of hexamethylenetetramines, heated up through about 60 minutes To 70 DEG C, reaction 5 hours at such a temperature.It should be noted that phenol and formalin Coordinating mol ratio (F/P) is 1.16.Then, the reactant liquor of gained is warming up to 90 DEG C, subtracts Press-dehydrating, thus obtains fusible type phenolic resin.

-embodiment 1-

The Flattery silica sand being heated to 145 DEG C by 7000 parts is put in sand muller, Putting into total amount with the compounding ratio (1:1) shown in table 1 below again is 175 parts above-mentioned The linear phenol-aldehyde resin obtained and fusible type phenolic resin, mixing 50 seconds.Then, by 0.9 Part is dissolved in 105 parts of water as the sodium hydroxide of the Arrhenius alkali of curing accelerator, will The solution being consequently formed supplies to sand muller, carries out mixing, until sand grains disintegrate, Then carry out air-supply cooling, add 7 parts of calcium stearates the most again, obtain shell mould RCS.

-embodiment 2～4-

Use 0.9 part of Lithium hydrate as Arrhenius alkali, calcium hydroxide or hydrogen-oxygen respectively Change potassium as curing accelerator, replace the sodium hydroxide in embodiment 1, in addition, according to Method similarly to Example 1 respectively obtains the RCS of embodiment 2～4.

-embodiment 5～11-

In embodiment 1, as curing accelerator, use 0.9 part respectively as cloth Lanace platform The sodium carbonate of alkali metal inorganic salt of moral alkali, sodium bicarbonate, potassium carbonate, lithium carbonate, sulfurous acid Sodium, sodium aluminate or sodium stannate trihydrate, in addition, according to side similarly to Example 1 Method respectively obtains the RCS of embodiment 5～11.

-embodiment 12～17-

In embodiment 1, as curing accelerator, use 3.5 parts respectively as cloth Lanace platform The sodium alginate of the alkaline metal organic salt of moral alkali, sodium salicylate, sodium benzoate, 1-naphthols-5 -sodium sulfonate, p-phenolsulfonic acid's sodium or paratoluenesulfonic acid sodium salt, in addition, according to embodiment 1 same method respectively obtains the RCS of embodiment 12～17.

-embodiment 18～21-

In embodiment 1, as curing accelerator, the ormal weight shown in Table 3 below is used The combination of Arrhenius alkali and brnsted base or brnsted base combination with one another, In addition, the various RCS of embodiment 18～21 are respectively obtained similarly to Example 1.

-embodiment 22～25-

Change as shown in table 4 making of linear phenol-aldehyde resin and fusible type phenolic resin in embodiment 6 By ratio, use the usage amount of sodium bicarbonate as shown in table 4 and sodium salicylate, in addition, Obtain the various RCS of embodiment 22～25 similarly to Example 6.

-embodiment 26～29-

In embodiment 1, as curing accelerator, use table 4 below, the regulation shown in 5 The Arrhenius alkali of amount and/or the combination of brnsted base and hexamethylenetetramine, except this with Outward, the various RCS of embodiment 26～29 are respectively obtained similarly to Example 1.

-embodiment 30-

The Flattery silica sand being heated to 145 DEG C by 7000 parts is put in sand muller, Put into wherein and coordinated 87.5 parts of linear phenol-aldehyde resins and 0.9 part of sodium bicarbonate to obtain in advance Material, mixing 50 seconds, adds 87.5 parts of fusible type phenolic resin the most again, carries out mixing, Until sand grains disintegrate, then carry out air-supply cooling, then add 7 parts of calcium stearates, obtain mesh Mark RCS.

-comparative example 1-

The Flattery silica sand being heated to 145 DEG C by 7000 parts is put in sand muller, The linear phenol-aldehyde resin manufactured before putting into 175 parts wherein, mixing 50 seconds, then adds Add and 26.3 parts of hexamethylenetetramines are dissolved in water the solution of formation as firming agent, mix Refining, until sand grains disintegrate.Then, carry out air-supply cooling, then add 7 parts of calcium stearates, Obtain RCS.

-comparative example 2-

Use fusible type phenolic resin to replace the linear phenol-aldehyde resin in comparative example 1, and do not add Add firming agent, in addition, obtain target RCS in the same manner as comparative example 1.

-comparative example 3,4-

In embodiment 1, do not use curing accelerator, or use 3.5 parts of tripolycyanamide generations For the sodium hydroxide as curing accelerator, in addition, obtain the most respectively To target RCS.

-evaluation of RCS characteristic-

For the various RCS obtained in above-described embodiment 1～30 and comparative example 1～4, according to Following determination of test method or evaluate its characteristic, its result is together shown in the composition of each RCS Table 1 below～table 6.

-mensuration of bending strength-

Use each RCS, according to JIS-K-6910, make JIS formula sample (10mm × 10mm × 60mm, firing condition: 250 DEG C × 60 seconds), obtains for this JIS formula sample, measures its bending strength (kgf/cm according to JACT test method(s): SM-1²)。 This bending strength is the highest, then it represents that casting mold is more for high intensity.

-mensuration of RCS fusion points-

For the fusion temperature of each RCS, according to JACT test method(s): C-1, (fusion points is tried Test method) it is measured.The fusion temperature of this mensuration is the highest, then the resistance to blocking of RCS is the most excellent Different.

-mensuration that bending (500gf) is measured-

According to the bending test method of JACT test method(s): SM-3, for using each RCS to obtain The each test film (180mm × 40mm × 5mm, firing condition: 250 DEG C × 40 seconds) arrived, Apply the loading of 500gf in the central portion, use amesdial (dial gauge) to read placement 3 The deflection (mm) of test film central part after minute, using this value as bending (500gf) amount. This amount of bow (deflection) is the operability after representing firm making molds and casting mold curing rate Standard index, this amount of bow is the least, then it represents that the curing rate of casting mold is the fastest, and operability is more Good.

-evaluation of anti-shelling-

Shelling test method(s) (the 5-2-1 rising sun organic material industry according to JACT test method(s): C-4 Method), evaluate the anti-shelling of each RCS.Specifically, by tipping bucket (dump box) to It is heated on the mould of 280 DEG C ± 2 DEG C of temperature supplying each RCS, after 40 seconds, from turning over Take apart a die on bucket, electric heater will be attached to the RCS on this mould and burn till to filbert, Make it solidify, thus on mould, form test film.Then, for the examination taken off on mould Test sheet, measure its quality, and by range estimation, the exfoliation state of RCS on its surface is carried out Evaluate, obtain anti-shelling mark.It should be noted that anti-shelling mark is without table by test film As 5 points during the stripping area of face, as 1 point when surface entirety is all peeled off, with 5 stages It is evaluated.Therefore, be 4 points when peeling off area and being 1/4,1/2 time be 3 points, 3/4 time It it is 2 points.Further, this anti-shelling mark is the biggest, then it represents that by being temporarily attached to heated mould The casting mold that RCS on tool is constituted is the fewest in the situation of its splitting or peeling.

Additionally, for the test film taken out from this mould, cut off its central part, measure respectively The central authorities of this section and the thickness at two ends, carry out the wall thickness at 3 positions different in test film Evaluate.The test film that the wall thickness at each position is thicker is the test film that anti-shelling is good, and The test film that the quantity at the position of more than 4mm thickness is the most, then it represents that anti-shelling is the best.

-mensuration of formaldehyde/ammonia generation amount-

In combustion tube, RCS each to 1000g heating 5 minutes at a temperature of 300 DEG C, separately On the one hand, take out the atmosphere gas in this combustion tube with the flow of 1L/ minute with pump, then, Formaldehyde gas in the atmosphere gas of this taking-up and ammonia are collected respectively the pure water of 40ml × 2 In.Then, with acetylacetone,2,4-pentanedione standard measure, this formalin obtained is carried out quantitatively, another Aspect, for the ammonia spirit obtained, is carried out quantitatively ammonia generation amount by titrimetry.Should Formaldehyde gas generation amount, ammonia generation amount are the most, then stink is the strongest, cause working environment more to be disliked Change.

From above-mentioned table 1～the result of table 6, each RCS's obtained in embodiment 1～30 Amount of bow is the lowest, additionally, in the evaluation of anti-shelling, anti-shelling mark is the highest, and really Recognize test film and also there is a lot of 4mm thicker portion with wall thickness.Therefore, for implementing The each RCS obtained in example 1～30, the curing rate of casting mold is fast, and can be effectively improved The operability of the casting mold after just moulding, and can advantageously contribute to prevent in the firm moulding of casting mold After the demoulding, carrying time fracture, the generation of slight crack etc., additionally, do not conform to when making molds The reduction of lattice rate and the raising aspect of productivity ratio are also advantageous.And, these embodiments 1～ Each RCS of 30 can realize the raising of anti-shelling, thus can be effectively improved casting mold wall thickness Uniformity, and can advantageously contribute to maintain casting mold intensity, eliminate casting time insert Enter defect, gas defects.

Additionally, for each RCS of this embodiment 1～30, owing to significantly reducing formaldehyde gas Body generation amount, ammonia generation amount, it is taken as that also be able to advantageously avoid such as comparative example 1 RCS uses conventional RCS that hexamethylenetetramine obtains as firming agent because of stink the most in a large number And the problem that the working environment caused deteriorates.

And then, each RCS of embodiment 1～30 in bending strength, fusion points at least one Individual aspect achieves significantly improvement, as such, it is advantageous to achieve the high intensity of casting mold, and And it also is able to be advantageously carried out the raising of resistance to blocking.Even if particularly confirming only to use on a small quantity Arrhenius alkali, brnsted base, the improvement effect of fusion points also becomes more significantly.

On the other hand confirm, be equivalent to the RCS obtained in the comparative example 1 of conventional RCS, Formaldehyde gas generation amount, ammonia generation amount are many, there is problem frowzy, and comparative example 1 RCS and the anti-shelling inequality of RCS of comparative example 2～4, additionally, fusion points, Amount of bow aspect is also poor than the RCS of embodiment 1～30.

Claims (15)

1. a mould using for organic binder, it is characterised in that by linear phenol-aldehyde resin, can Melt the group of type phenolic resin and the curing accelerator of the curing reaction that can promote these phenolic resin Close and formed, and the usage rate of this linear phenol-aldehyde resin A and this fusible type bakelite B It is calculated as A:B=95:5～5:95 with quality criteria, meanwhile, as this curing accelerator, At least contain Arrhenius alkali and/or brnsted base.

2. mould using for organic binder as claimed in claim 1, it is characterised in that as Described Arrhenius alkali, uses Ah the tiring out Buddhist nun that pH is 10～14 crow of 0.1mol/l aqueous solution At least one of this alkali.

3. mould using for organic binder as claimed in claim 2, it is characterised in that described Arrhenius alkali is selected from sodium hydroxide, Lithium hydrate, calcium hydroxide and potassium hydroxide.

4. mould using for organic binder as claimed in claim 1, it is characterised in that as Described brnsted base, use 0.1mol/l aqueous solution the alkali metal that pH is 8～14 without At least one of machine salt.

5. mould using for organic binder as claimed in claim 4, it is characterised in that described Alkali metal inorganic salt selected from sodium carbonate, sodium bicarbonate, potassium carbonate, lithium carbonate, sodium sulfite, Sodium aluminate and sodium stannate trihydrate.

6. mould using for organic binder as claimed in claim 1, it is characterised in that as Described brnsted base, uses the alkali metal that pH is 2～7.5 of 0.1mol/l aqueous solution to have At least one of machine salt.

7. mould using for organic binder as claimed in claim 6, it is characterised in that described Alkaline metal organic salt is selected from sodium alginate, sodium salicylate, sodium benzoate, 1-naphthols-5-sulphur Acid sodium, p-phenolsulfonic acid's sodium and paratoluenesulfonic acid sodium salt.

8. the mould using for organic binder as according to any one of claim 1～7, wherein, Total amount 100 mass relative to described linear phenol-aldehyde resin Yu described fusible type phenolic resin Part, described Arrhenius alkali and/or brnsted base the total of the curing accelerator formed Amount is in the range of 0.2～15 mass parts.

9. the mould using for organic binder as according to any one of claim 1～7, its feature It is, further with relative to described linear phenol-aldehyde resin and the conjunction of described fusible type phenolic resin The ratio below 5 mass parts of measuring for 100 mass parts contains hexamethylenetetramine.

10. mould using for organic binder as claimed in claim 8, it is characterised in that enter Step is with relative to described linear phenol-aldehyde resin and total amount 100 matter of described fusible type phenolic resin For amount part, the ratio below 5 mass parts contains hexamethylenetetramine.

11. 1 kinds of molding sand compositions, it is characterised in that use in claim 1～10 arbitrary Mould using for organic binder described in Xiang, and described mould using for organic binder is mixing with molding sand And formed.

12. molding sand compositions as claimed in claim 11, wherein, relative to molding sand 100 Mass parts, described mould using for organic binder carries out mixing with the ratio of 0.2～10 mass parts.

13. molding sand compositions as described in claim 11 or 12, wherein, described line style phenol The resin compound of urea formaldehyde and described fusible type phenolic resin is before described curing accelerator Mixing with described molding sand.

14. molding sand compositions as described in claim 11 or 12, wherein, have coordinated described The described linear phenol-aldehyde resin of curing accelerator and described fusible type phenolic resin respectively with institute State molding sand mixing.

15. 1 kinds of casting molds, it is characterised in that use institute any one of claim 11～14 The molding sand composition stated carries out moulding, and is heating and curing and is formed.