Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22C—FOUNDRY MOULDING
  • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
  • B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
  • B22C1/20—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents
  • B22C1/22—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins
  • B22C1/2233—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
  • B22C1/2246—Condensation polymers of aldehydes and ketones
  • B22C1/2253—Condensation polymers of aldehydes and ketones with phenols
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22C—FOUNDRY MOULDING
  • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
  • B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
  • B22C1/20—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents
  • B22C1/22—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins
  • B22C1/2233—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of resins or rosins obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
  • B22C1/2273—Polyurethanes; Polyisocyanates
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22C—FOUNDRY MOULDING
  • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
  • B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
  • B22C1/20—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22C—FOUNDRY MOULDING
  • B22C9/00—Moulds or cores; Moulding processes
  • B22C9/06—Permanent moulds for shaped castings
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22C—FOUNDRY MOULDING
  • B22C9/00—Moulds or cores; Moulding processes
  • B22C9/10—Cores; Manufacture or installation of cores
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/54—Polycondensates of aldehydes
  • C08G18/542—Polycondensates of aldehydes with phenols
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
  • C08G18/72—Polyisocyanates or polyisothiocyanates
  • C08G18/74—Polyisocyanates or polyisothiocyanates cyclic
  • C08G18/76—Polyisocyanates or polyisothiocyanates cyclic aromatic
  • C08G18/7657—Polyisocyanates or polyisothiocyanates cyclic aromatic containing two or more aromatic rings

Definitions

• Binder systems typically have an excess of NCO groups of up to 20%, based on the number of OH groups,
• the total amount of binder is usually in the range of foundry cores and foundry molds about 1% up 2% based on the mass of molding material used, and for feeders usually in the range of about 5% to 18% based on the other constituents of the feeder mass.
• the molding material mixture is then molded.
• Phenolic resin with etherified methylol groups Phenolic resin with etherified methylol groups
• the number of isocyanate groups of the polyisocyanate in the polyisocyanate component (ii) is preferably less than 80%, preferably 70% to 78% of the number of free hydroxyl groups of the ortho-fused phenolic resole in the Phenol resin component (i).
• the term likewise includes the "benzyl ether resins (ortho-phenolic resoles)" specified in VDG leaflet R 305 "Urethane cold box process” (February 1998) under 3.1.1.
• the term also includes the "phenol resins of the benzyl ether resin type" disclosed in EP 1 057 554 B1, see in particular paragraphs [0004] to [0006].
• the ortho-condensed phenolic resole of the phenolic resin component (i) to be used according to the invention has free methylol groups -CH 2 OH and / or etherified methylol groups -CH 2 OR.
• the ortho-fused phenolic resole of the phenolic resin component (i) is a modified resol comprising condensed phenolic resole units as described above, which are substituted and / or linked by esters of orthosilicic acid.
• Such resins are preparable by reacting free hydroxy groups (i.e., hydroxy groups of the unetherified methylol groups) of an ortho-fused phenolic resole with one or more esters of orthosilicic acid.
• Such modified resols and their preparation are described i.a. described in the patent application WO 2009/130335.
• the phenolic resin component comprises (i) an ortho-fused phenolic resole having free methylol groups and a solvent and optionally one or more additives.
• the polyisocyanate component (ii) of the two-component binder system according to the invention contains no polyisocyanate in the form of isocyanate compounds having at least two isocyanate groups per molecule, which furthermore have at least one carbodiimide group per molecule.
• the phenolic resin component (i) of the two-component binder system according to the invention comprises a solvent in which the above-described ortho- condensed phenolic resole is dissolved.
• the solvent for the phenolic resin component (i) comprises the constituents
• the solvent of the phenol resin component is free of aromatic compounds and / or the solvent of the polyisocyanate component is free of aromatic compounds. Accordingly, the above-mentioned solvents are not preferred substituted benzenes and naphthalenes, as well as substances selected from the group consisting of cashew nut shell oil, components of cashew nut shell oil and derivatives of cashew nut shell oil. In the case of substances from the group comprising cashew nut shell oil, components of cashew nut shell oil and derivatives of cashew nut shell oil, however, this disadvantage is counteracted by the advantage of recovering from renewable raw materials.
• the solvent of the phenolic resin component (i) and the solvent of the polyisocyanate component (ii) are free of aromatic compounds.
• phenolic resin component (i) and / or the polyisocyanate component (ii) comprises as additive one or more substances which are selected from the Group consisting of
• Acid chlorides e.g. Phosphoryl chloride, phthaloyl chloride and benzene phosphorous dichloride
• weight percentages are based on the total amount of the components (av), (bv) and (cv) in the premix.
• additives optionally contained in the phenolic resin component (i) and / or in the polyisocyanate component (ii) of the two-component binder system according to the invention consist in facilitating the removal of hardened feeders, foundry cores and foundry molds from the mold and in increasing the Storage stability, in particular moisture resistance, prepared feeders, foundry cores and foundry molds.
• the ratio of the mass of polyisocyanate to the mass of ortho-fused phenolic resole having etherified and / or free methylol groups is less than 1, 1, preferably less than 1.0, and at least 0.5.
• Such a mixture according to the invention can be used as a molding material mixture for producing a foundry mold or a foundry core according to the polyurethane-cold-box process.
• This mixture according to the invention in particular in its preferred embodiments, is characterized in that produced foundry molds and foundry cores have sufficient strength at a low binder content and with a small amount of tertiary amine. Due to the small amounts of binder and tertiary amine, the emissions, in particular of BTX aromatics, and the odor pollution are limited.
• (A) can be prepared by mixing the components of the two-component binder system according to the invention as defined above,
• mold base all mold bases commonly used for the production of feeders, foundry molds and foundry cores are suitable as indicated above.
• the process according to the invention in particular in its preferred embodiments, is characterized in that it allows the production of feeders, foundry molds and foundry cores with a low binder content and addition of a small amount of tertiary amine, without compromising the strength of the feeders, foundry molds and foundry cores , Due to the small amounts of binder and tertiary amine, the emissions, in particular of BTX aromatics, and the odor pollution are limited.
• the finished molding material mixture is filled directly after its preparation described above in the shooting head of Kernsch manmaschine.
• the parameters of the core shooting process are as follows: Shot time: 3 seconds, delay time after shot: 5 seconds, shooting pressure: 4 bar (400kPa).
• the test specimens are gassed for 10 seconds at a gassing pressure of 2 bar (200 kPa) with dimethylisopropylamine (DMIPA).
• DMIPA dimethylisopropylamine
• the dosage of the DMIPA (see Table 4) is effected by means of an injection needle.
• air is purged for 9 seconds at a purging pressure of 4 bar (400 kPa).
• the initial flexural strength is measured with a LRu-2e Multiserw tester at 15 seconds after flushing.
• the phenolic resin component (i) contains a solvent comprising dimethyl esters of C 4 -C 6 dicarboxylic acids (LM1) and tetraethyl silicate (TES) (LM2).
• LM1 dimethyl esters of C 4 -C 6 dicarboxylic acids
• TES tetraethyl silicate
• the phenolic resin component (i) contains a solvent comprising the ingredients
• LM4 rapeseed oil methyl ester (Examples 6.1-6.4, 7.1, 7.2).
• Examples 1.3, 2.3, 3, 4. 5.1-5.3, 6.1-6.3, 7.1, 7.2, 8.1, 8.2, 9.1 and 9.2 contrast the mass ratio of polyisocyanate MDI to resole and the total mass of polyisocyanate MDI and resole in the molding material mixture reduced the reference examples.
• comparable or even higher flexural strengths are achieved than in the reference examples, although the binder content of the molding material mixture is smaller than in the reference examples.
• the binder system of the invention is also more reactive than the binder system of the reference examples, because even at significantly lower levels of DMIPA high initial flexural strengths are obtained.
• LM 3 and LM 4 are conventional solvents for phenolic resins in the polyurethane cold box process.
• BTX aromatics aromatic compounds
• the use of LM3 is not preferred.
• tetraethyl silicate As the content of tetraethyl silicate (LM 2, Inventive Examples 4, 5-1-5.3, 6.1-6.3, 7.1, 7.2, 8.1, 8.2, 9.1 and 9.2) increases, the strength values increase in comparison with Examples 5.4 and 6.4 not according to the invention. This shows that tetraethyl silicate also brings about an improvement in combination with conventional solvents for phenolic resins in the polyurethane cold box process.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Mold Materials And Core Materials (AREA)
• Polyurethanes Or Polyureas (AREA)
• Adhesives Or Adhesive Processes (AREA)

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• 2015
  • 2015-01-30 DE DE102015201614.5A patent/DE102015201614A1/de active Pending
  • 2015-09-10 KR KR1020177009685A patent/KR102344347B1/ko active IP Right Grant
  • 2015-09-10 CA CA2960695A patent/CA2960695C/en active Active
  • 2015-09-10 BR BR112017004706-3A patent/BR112017004706B1/pt active IP Right Grant
  • 2015-09-10 US US15/510,460 patent/US20170282239A1/en not_active Abandoned
  • 2015-09-10 WO PCT/EP2015/070751 patent/WO2016038156A1/de active Application Filing
  • 2015-09-10 EP EP15766090.3A patent/EP3191239A1/de active Pending
  • 2015-09-10 EA EA201790567A patent/EA033864B1/ru not_active IP Right Cessation
  • 2015-09-10 CN CN201580048921.8A patent/CN107073559B/zh active Active
  • 2015-09-10 MX MX2017003158A patent/MX2017003158A/es unknown
  • 2015-09-10 JP JP2017513746A patent/JP6650927B2/ja active Active
• 2017
  • 2017-03-09 ZA ZA2017/01720A patent/ZA201701720B/en unknown

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