JPS6049830A - Production of casting mold - Google Patents

Abstract

PURPOSE:To improve the collapsing property of a casting mold by heating the coated sand on which a compsn. contg. a block isocyanate compd. and a resol type phenolic resin is coated to cure said sand and to have the urethane bond resulting from the reaction of methyrol group and hydroxyl group, etc. generated by such curing. CONSTITUTION:The resulting product of addition reaction of a polyisocyanate compd. and an isocyanate block agent is used as a block isocyanate compd. A resol resin for which a bisphenol or the like is used for the purpose of maintaining the dry strength of the sand is used as a resol type phenolic resin. Said resin is obtd. by bringing 1.5-4.0mol formaldehyde into reaction with 1mol bisphenol A. The heating temp. in the stage of manufacturing the casting mold is 150-350 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing casting metal, and is particularly applicable to castings with relatively low casting temperature, such as aluminum castings and alloy castings. Degradability of the mold! 1: This relates to a significantly improved method of manufacturing a mold.

Conventionally, there have been numerous processes for manufacturing limited quantities, but the shell molding method has been used in the automobile industry for phenolic resins because it has excellent dimensional stability of the mold, good mold skin, and quick curing. Widely used in the center. However, when used in a mold with a low pouring temperature such as an aluminum casting, the mold has poor disintegration properties and requires heat treatment for 6 to 12 hours at a surface temperature of about 500°C, which prevents the mold from pouring. Sand removal work requires a huge amount of cost and labor. Therefore, in order to improve the disintegration of the mold, polyisocyanate and polyol were added to the foundry river sand, and it was hardened with amine scum! :2 The method is one shot, and LC has a problem with Aminekasu's agility and energy countermeasures. Furthermore, a highly visible Saki-type R Hanito-Kinto was developed in which polyincyanate and amine-based polyol were added to foundry river sand, but there was a problem in that it took a long time until the ``fc'' was graded.

Therefore, the casting Raikai shell mold method and the next one Zl'
There is a strong demand for the development of a method for producing electricity that can be produced using the following methods:

In the present invention, TL- reduces and facilitates heat treatment.

A composition containing a block-in/anate compound and a resin-type phenolic resin was added to the foundry sand, which was developed by intensively studying the current shell mold method and the manufacturing method of molds that can produce I'JQ'P strips. Kad Yabusa for the downfall
Is it graded by heat and shaped into pieces? The disintegration properties of the cast molding have been significantly improved by using the molding method, and the current shell molding method and 11-item (fluidity of sand, hardening speed)
I discovered that it is possible.

In other words, according to the invention, the above is the same; sand is heated to 150°C to 650°C, and the mold is heated to 650°C.
IX chisei and the block oki of the block-in-a-to compound are 41 #1 generated in cyanate compound 9, and 1 m of lene-type phenol (the methylol group and hydroxyl group of Mk are The mold becomes strong due to the urethane bond that reacts and becomes strong enough to be removed from the mold.Also, the mold collapses significantly.It is thought that the cracking is due to the use of the urethane bond in forming the mold.

The block isocyanate compound used in the composition used in the present invention is an addition reaction product of a polyinyanate compound and an incyanate block. As the polyisocyanate compound, FI [any of the incyanate compounds known in the United States or the incyanate compounds having two or more atoms can be used, and these polyisocyanates -
compounds and ethylene glycol, globylene glycol
Le, to! 1 opposite ratio to active hydrogenated adducts such as metherol proha/, glycerin, and polyether polyol.
Compounds containing terminal incyanate groups may also be used.

As the incyanate block, it is possible to use not only those that have not been used conventionally, but also seven alcohols such as phenol, cresol, xylenol, and nonylphenol. Active methylene compounds such as alcoholic acid, acenaracetone, and malonated diesters, aromatic amines such as menalaniline and ginylamine, phthalate imides, lactams such as ε-cabrocyctam, and ethylene imine. imines such as

There are urinary tracts, oxime hammers, urinary tracts, and boric acids. Blockison anate compound q/
J is obtained by the above-mentioned isocyanate conversion method, the isocyanate conversion process, and the known method. The samurai will respond.

Father 1 The V-sol type phenol resin used in the present invention is preferably a resol using bisphenol pickling for sand & dirt retention. η (for example, methylol group 7j 7 , r-nol) lE jD, f can be used in any form, and the synthesis of resol-type phenol is not limited to phenol. , cresol.

Bisphenol A1 Bisphenol S, Bisphenol F = 4. Phenol cheeks and formaldehyde of NaO
Using a synthetic catalyst such as H, Ba (OH, ammonia, trimethylamine, etc.)
0 resol-type bisphenol iD, (ah tojitege, to bisphenol, hisphenol S1 bisphenol F No. bisphenol and formaldehyde)
z lNaOH, Ba (OH% ammonia, trimethylamine) is reacted using a catalyst τ. Formaldehyde is 1.5-4.0
The mole is reacted and served, and the gradient 4LljII is preferably used. If formaldehyde is less than 1.5 mol, methylol production will be low and 191II! ! The rate of reaction is slow
Furthermore, if the total amount of formaldehyde exceeds 4.0 moles, the odor of formaldehyde will become strong during JD thermal imaging of the sand mold, which is not preferable.

90 to 18
When heated to 0°C, μj material sand solid or Irl m
a(1) Blocked incyanate compound and resol-type resin (1) are stirred and mixed, and during this weighting step, the necessary VC and the common medium τ are evaporated to increase the uniformity.Casting. When the temperature of the sand reaches 180'C, the dissociation of the prosotysocyanate compound 'IyA' becomes a carp, and the life of the character is shortened and the frequency of sand molding is reduced. Also, the temperature is lower than 90℃, the handling axis of the resin is insufficient, and the bath medium is not good.
It's not good enough, and it's 1, 7, or 1 point, which is unfavorable for Prono Kings.

Also used are blocked incyate compounds and phenol 4fl I! The convex ratio of the ratio (Rindou ratio) (R95:57111 and 5:95 is used in the hase convexity is 85:, 157) - 50 near 0 in the single-legged four. It will be done. If the block isocyanate compound is used too many times, the curing will be slow, and if the resol type phenol side is used with 4 μm or more, the sand mold glue will be destroyed.

The heating temperature range when applying IR for the father's disease type is 150'C; ~65
φゐ at 0℃. Below 150℃, the hardening of the 64''Cψ core and the composition slows down, and above 650℃, the coercive force of iron 4 decreases and 1ζ
The skin of the $b seat is a shame. is 0 to 0.6 ri for casting river sand.
The percentage is 6.0 to 0.5%. 6. If the amount of 6% added to the fat base exceeds 7%, it will not only cause defects in the foot of the product, but also cause 1 + ft + weight (9 not good. Also 0
, With 5% wood droplets, the frequency of sand molding is low, and Vc1 needles cannot be used for practical purposes.

In addition, in the present invention, the anti-proboscis used in the treatment of maple sand can be used to block infiltration of the compound of dibutyl tin dilaurate, stannic chloride, etc. ,
Nanten, even if you blame Cobalt, please (Kurokoichi 7I)
In II payment, there is o, 0 + ~ 1.0 raw w%-c for the part of the kanji.

In addition, the thoracic tube's use of ``1'' is treated as ``1'' (: Ui; the stearin that is used in the 7 Hermold method to make it a woman's body is a wave of calcium). Nalu AI
Even if Jt is added, it will also be necessary to remove the sand plate mounting plate for casting proboscis.

There are no particular restrictions on the method of mixing the flocked incyanate compound 9 and the resol type phenolic resin. Good too.

The foundry river sand used in the present invention may be any of those normally used for νj materials, and zircon sand and oripin sand can also be used in one step.

An example of the uninvented Mei hIII is shown below.

Example 1 (Synthesis of resol type phenolic resin) Bisphenol A22 was placed in a four-bottle flask with a reflux condenser 916.
Add 80g 57% formalin 1620g and 20% Na
Add 40 g of OH water and react at reflux temperature for 2 hours to obtain a solid resin. Powerfully heated footer 1 no silica sand 8kg
K Coronet) AP Stable (manufactured by H Honbo 1 Urethane Co., Ltd., isocyanate compound masked with phenol,
Softening point: 100" Mixed for 20 seconds and mixed for 20 seconds, the 0 sand type sand was mixed with Hori-I VC.
c771! J*e 8 kg, 100 g of Coronate AP staples, and a bath solution consisting of 60 g of acetone and Example 1
1. Add 8 g of dissolved calcium stearin and mix the bath solution for 20 seconds with stirring in a container until the sand collapses. Tin) 'IIIJ for I stand ■ Ha'
Is the 0 sand mold custom made table 1 where fL Enoki sand was obtained?
l15 Mixed #l [8 kg of flata 1-no silica sand heated to 160°C
K Ri L / 5 N cross linking agent U
T (manufactured by Bayer Urethane GmbH, incyanate compound masked with ε-caprolactam, softening and disintegration + 00
℃) 100 gk7JVLc40 secondsm mixed defect Example 1 resol type fuz / -k4A
Mix 4 pieces of 60 g of methanol and 30 g of methanol with the bath liquid until the sand collapses.

The mixture was mixed in the same direction for 20 seconds to obtain sand covered with fat.

Table 1Vc shows the characteristics of the sand mold.

Example 4 Except for dibutyltin dilaurate, sand was obtained using the same methods as Example 6 and IO2. Sand mold characteristics 7 are shown in Table-1.

Comparative Example 1 (Novok type phenol 17J I nail 8171
) 1880 g of phenol in a 4-long lasco equipped with a laminar flow condenser. 57% formalin 244g. Add 488g of 80% paraformaldehyde and 4g of oxalic acid? r 硲〃
Talk back. After reacting for 5 hours in a No. 11 machine, the solid TiLI fat was removed by quick dehydration and #condensation. NLC Noholac Phenolic Resin 0
Stir with all your might for 40 seconds, pour 24g of xamethylenetetramine and 7XdOg77 into the mixed bales, and mix vigorously until the sand crumbles. Add 8 g of calcium and mix for 20 seconds. Table IK shows the physical properties of the sand mold.

Comparative Example 2 Kneading VC (heated to 160℃)
gVC Coronate AP, z. Using 100g of table and Comparative Example 1, 60g of nπ novolac type phenol street resin was mixed until the sand collapsed and the mixture was mixed.

After that, stearin relative calcium 8gt7IIJ Eshini 2
Mix for 0 seconds and pour out the foundry sand.

The physical properties of the sand mold are listed below.

Comparative Example 6 Nratari silica sand heated to 110°C in a kneader 8K
g ic:yonate AP tape #10 [a solution consisting of 1g and 60g of acetone and sannisox)] S-
20y' (Sanyo Kasei Kokuri Co., Ltd., Sucrose yarn polyol viscosity approximately 70 PI3 5℃) sag and A7ton 5
0 g77・ra l/) Add ash and mix for 1 dJ for 6 minutes. π Stearin Enemy Calcium Bgk) JDχ Mix for another 20 seconds.

Sand mold characteristics: Softness - 1 as shown in 〇*・ *1 Bending"jMe' JIS K 6 9 1
0 method Vc Te#4w*2 Melting point 2 JACT method 1] Mud GQ-6 Sand mold collapse i: Heated to 250℃ 7j30φX5om
A test piece is prepared by putting foundry sand in a NLH mold and curing it for 6 minutes in a 400"C electric furnace. Heat the mold to 500'C in a non-dispersible state. Shunpō Reitōi is baked in a 500°C oven for 20 minutes.

This test piece was placed on a 28-mesh sieve, and the rotor tab was used for 1 minute of IijJ and 9 strokes using a rotor tube of 2 and 2.
Flat plate mold 70X140 set in sub-constant vortex l building
111+1J: Koroku = YoJ Kinsan inner dimension 5 0 X 1 2
QInJ [1 δ 5 mmt Straighten 1 J Suitable position J Fat handling bale Sand button light sill t Furnace cylinder 650℃ IC 40 seconds and then scissors 9 out After 10 seconds, straighten 500 g on the odor with distance between fulcrums IQQm + n Measure the amount of deflection when multiplied by k
It is advantageous that items with low embroidery and a small number of weights and weights are quickly graded.

By using the molding method according to the present invention, it is possible to create a sand mold equivalent to the shell mold method.
A structure that has the hardening speed of a sand mold and has excellent mold collapse resistance! Is it impossible to serve you?0 11 Takeq-

Claims (1)

[Scope of Claims] 1. Hardening of foundry resin enucleated sand containing block incyanate compound and resol-type phenol resin in foundry river sand using Calothermal heat. #Yumanbi of the mold. 26 The resol m phenolic resin must be a resol bisphenol oil with a formaldehyde content of 1.5 to 4. [Claim 1 or 2]
A method for manufacturing a mold for mounting a tomb. 4. Make sure that the heating temperature is between 150℃ and 550℃.
A method for manufacturing an @-type according to claim 1, which includes Ff copying.