JPS63123858A - Binder for forming ceramic powder - Google Patents
Binder for forming ceramic powderInfo
- Publication number
- JPS63123858A JPS63123858A JP61268681A JP26868186A JPS63123858A JP S63123858 A JPS63123858 A JP S63123858A JP 61268681 A JP61268681 A JP 61268681A JP 26868186 A JP26868186 A JP 26868186A JP S63123858 A JPS63123858 A JP S63123858A
- Authority
- JP
- Japan
- Prior art keywords
- binder
- formulas
- ceramic powder
- tables
- parts
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000919 ceramic Substances 0.000 title claims description 28
- 239000000843 powder Substances 0.000 title claims description 21
- 239000011230 binding agent Substances 0.000 title claims description 18
- 229920006322 acrylamide copolymer Polymers 0.000 claims description 6
- 238000000465 moulding Methods 0.000 claims description 6
- DUZXVLRTMFAOLX-UHFFFAOYSA-N ethenyl acetate;prop-2-enamide Chemical compound NC(=O)C=C.CC(=O)OC=C DUZXVLRTMFAOLX-UHFFFAOYSA-N 0.000 claims description 5
- 125000004432 carbon atom Chemical group C* 0.000 claims description 4
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 3
- 229930195734 saturated hydrocarbon Natural products 0.000 claims description 3
- 239000001257 hydrogen Substances 0.000 claims description 2
- 229910052739 hydrogen Inorganic materials 0.000 claims description 2
- 239000000126 substance Substances 0.000 claims 5
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 21
- 229920001577 copolymer Polymers 0.000 description 12
- 238000000034 method Methods 0.000 description 12
- 239000000203 mixture Substances 0.000 description 11
- 229920002554 vinyl polymer Polymers 0.000 description 10
- 150000001241 acetals Chemical class 0.000 description 9
- 239000002904 solvent Substances 0.000 description 9
- DHKHKXVYLBGOIT-UHFFFAOYSA-N 1,1-Diethoxyethane Chemical compound CCOC(C)OCC DHKHKXVYLBGOIT-UHFFFAOYSA-N 0.000 description 8
- HRPVXLWXLXDGHG-UHFFFAOYSA-N Acrylamide Chemical group NC(=O)C=C HRPVXLWXLXDGHG-UHFFFAOYSA-N 0.000 description 8
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 7
- 239000002245 particle Substances 0.000 description 7
- 238000006116 polymerization reaction Methods 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 6
- 230000000704 physical effect Effects 0.000 description 5
- 229920000642 polymer Polymers 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- 238000005336 cracking Methods 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- 239000003377 acid catalyst Substances 0.000 description 3
- 150000001299 aldehydes Chemical class 0.000 description 3
- -1 amine compounds Chemical class 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 239000000178 monomer Substances 0.000 description 3
- 230000003472 neutralizing effect Effects 0.000 description 3
- 229920002037 poly(vinyl butyral) polymer Polymers 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- LTPBRCUWZOMYOC-UHFFFAOYSA-N Beryllium oxide Chemical compound O=[Be] LTPBRCUWZOMYOC-UHFFFAOYSA-N 0.000 description 2
- ZTQSAGDEMFDKMZ-UHFFFAOYSA-N Butyraldehyde Chemical compound CCCC=O ZTQSAGDEMFDKMZ-UHFFFAOYSA-N 0.000 description 2
- IMROMDMJAWUWLK-UHFFFAOYSA-N Ethenol Chemical group OC=C IMROMDMJAWUWLK-UHFFFAOYSA-N 0.000 description 2
- 239000004372 Polyvinyl alcohol Substances 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- XSTXAVWGXDQKEL-UHFFFAOYSA-N Trichloroethylene Chemical group ClC=C(Cl)Cl XSTXAVWGXDQKEL-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 238000006359 acetalization reaction Methods 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 238000005266 casting Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 238000010528 free radical solution polymerization reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000003505 polymerization initiator Substances 0.000 description 2
- 229920002451 polyvinyl alcohol Polymers 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000004080 punching Methods 0.000 description 2
- 238000010992 reflux Methods 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- JNYAEWCLZODPBN-JGWLITMVSA-N (2r,3r,4s)-2-[(1r)-1,2-dihydroxyethyl]oxolane-3,4-diol Chemical compound OC[C@@H](O)[C@H]1OC[C@H](O)[C@H]1O JNYAEWCLZODPBN-JGWLITMVSA-N 0.000 description 1
- HZAXFHJVJLSVMW-UHFFFAOYSA-N 2-Aminoethan-1-ol Chemical compound NCCO HZAXFHJVJLSVMW-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- CYTYCFOTNPOANT-UHFFFAOYSA-N Perchloroethylene Chemical group ClC(Cl)=C(Cl)Cl CYTYCFOTNPOANT-UHFFFAOYSA-N 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- FNYLWPVRPXGIIP-UHFFFAOYSA-N Triamterene Chemical compound NC1=NC2=NC(N)=NC(N)=C2N=C1C1=CC=CC=C1 FNYLWPVRPXGIIP-UHFFFAOYSA-N 0.000 description 1
- 239000011354 acetal resin Substances 0.000 description 1
- IKHGUXGNUITLKF-XPULMUKRSA-N acetaldehyde Chemical compound [14CH]([14CH3])=O IKHGUXGNUITLKF-XPULMUKRSA-N 0.000 description 1
- 230000001476 alcoholic effect Effects 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 229910052784 alkaline earth metal Inorganic materials 0.000 description 1
- 150000001342 alkaline earth metals Chemical class 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 1
- 229910002113 barium titanate Inorganic materials 0.000 description 1
- 238000012662 bulk polymerization Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- BXKDSDJJOVIHMX-UHFFFAOYSA-N edrophonium chloride Chemical group [Cl-].CC[N+](C)(C)C1=CC=CC(O)=C1 BXKDSDJJOVIHMX-UHFFFAOYSA-N 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- HDERJYVLTPVNRI-UHFFFAOYSA-N ethene;ethenyl acetate Chemical group C=C.CC(=O)OC=C HDERJYVLTPVNRI-UHFFFAOYSA-N 0.000 description 1
- 229920001038 ethylene copolymer Polymers 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical group [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 239000003999 initiator Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 150000002576 ketones Chemical class 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 125000001477 organic nitrogen group Chemical group 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- XNGIFLGASWRNHJ-UHFFFAOYSA-L phthalate(2-) Chemical compound [O-]C(=O)C1=CC=CC=C1C([O-])=O XNGIFLGASWRNHJ-UHFFFAOYSA-L 0.000 description 1
- 239000004014 plasticizer Substances 0.000 description 1
- 229920000139 polyethylene terephthalate Polymers 0.000 description 1
- 239000005020 polyethylene terephthalate Substances 0.000 description 1
- 229920006324 polyoxymethylene Polymers 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 238000007127 saponification reaction Methods 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000010557 suspension polymerization reaction Methods 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 238000010345 tape casting Methods 0.000 description 1
- 238000009864 tensile test Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 229950011008 tetrachloroethylene Drugs 0.000 description 1
- HGBOYTHUEUWSSQ-UHFFFAOYSA-N valeric aldehyde Natural products CCCCC=O HGBOYTHUEUWSSQ-UHFFFAOYSA-N 0.000 description 1
- RXPRRQLKFXBCSJ-GIVPXCGWSA-N vincamine Chemical group C1=CC=C2C(CCN3CCC4)=C5[C@@H]3[C@]4(CC)C[C@](O)(C(=O)OC)N5C2=C1 RXPRRQLKFXBCSJ-GIVPXCGWSA-N 0.000 description 1
- 239000000052 vinegar Substances 0.000 description 1
- 235000021419 vinegar Nutrition 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は微細なセラミック粉体を用いた表面平滑性に優
れ緻密なセラミック成形体を得るに適した成形用バイン
ダーに関するものであり、さらにくわしくは、平均粒径
１μｍ以下のセラミック粉体であっても良好なセラミッ
ク成形体を得るに通した成形用バインダーに関するもの
である。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a molding binder that uses fine ceramic powder and is suitable for obtaining a dense ceramic molded body with excellent surface smoothness. relates to a molding binder that can produce good ceramic molded bodies even with ceramic powder having an average particle size of 1 μm or less.
ポリビニルアルコールをアセタール化したポリビニルア
セタール樹脂は、接着強度、強じん性等の諸物性に優れ
ており、近年特にセラミック分野の発展に伴い、セラミ
ックバインダーとして実用化されている。特に、にフタ
−デレーｒを用い次テープキャスト法によるグリーン・
シートの作成用バインダーとしてポリビニルアセタール
が使用されている。特公昭５４−８３６２号公報に低重
合度と高重合度のポリビニルブチラールを混合して用い
ている例があるが、高重合度ポリビニルブチラールの溶
解がおそく、溶解により急激な粘度上昇が起り、そのた
めセラミック粉の混合分散不良となり易くなりグリーン
シートのヒビ割れの原因になるという問題がある。１之
、特開昭６０−５４９６７号公報に記載されているよう
に、酢酸ビニル−エチレン共重合体ケン化物のブチラー
ル化物はエチレン成分が存在する九めに可塑性に富むが
その反面引張強度が弱く接着性が劣るためにグリーン・
シート加工時、割れが入り易いなどの問題点がある。Polyvinyl acetal resin, which is made by acetalizing polyvinyl alcohol, has excellent physical properties such as adhesive strength and toughness, and has been put into practical use as a ceramic binder in recent years, especially with the development of the ceramic field. In particular, green casting by the following tape casting method using a lidder
Polyvinyl acetal is used as a binder for making sheets. Japanese Patent Publication No. 54-8362 has an example of using a mixture of polyvinyl butyral with a low degree of polymerization and a polyvinyl butyral with a high degree of polymerization, but the dissolution of the high degree of polymerization polyvinyl butyral is slow, and the dissolution causes a rapid increase in viscosity. There is a problem in that the ceramic powder tends to be mixed and dispersed poorly, causing cracks in the green sheet. 1. As described in JP-A No. 60-54967, the butyralized product of saponified vinyl acetate-ethylene copolymer has high plasticity due to the presence of an ethylene component, but on the other hand, it has low tensile strength. Green due to poor adhesion
There are problems such as easy cracking during sheet processing.
看近では、表面平滑性を重視したより高品質のセラミッ
ク・シートが要求され、増々セラミック粉の微粉末化が
進んでいる。そのためセラミック粉の表面積が著しく増
加し、キレンのないグリーン・シートを製造するために
はこれまでよりも高分散性でかつ強じんなバインダーが
望まれている。In recent years, there has been a demand for higher quality ceramic sheets with an emphasis on surface smoothness, and more and more ceramic powders are being made into fine powders. As a result, the surface area of ceramic powder has increased significantly, and binders with higher dispersibility and toughness than ever before are desired in order to produce green sheets free of oxidation.
従来のバインダーではセラミック粉の微細化に対して、
よりバインダー量を増加して対応する九めに、乾燥した
グリーン・シート表面の７クレ現象や端部の巻上り現象
が発生し、さらにキャリアーフィルムからのハクリ性に
も問題が起り、歩留りが低く生産性が上がらない。又グ
リーン・シートの打抜き加工時の伸び、寸法安定性にも
問題がある。このような問題点に鑑み、本出願人に特願
昭６１−４４０９４号明細書に於て、上記問題点の改良
を提案した。本発明は、アクリル酸部分とアクリルアミ
ド部分会分子中に存在させることにより、それを更に改
良するものである。With conventional binders, it is difficult to finely refine ceramic powder.
However, when the amount of binder was increased, cracking phenomenon on the surface of the dried green sheet and curling up of the edges occurred, and problems occurred in peeling from the carrier film, resulting in a low yield. Productivity does not increase. There are also problems with elongation and dimensional stability during punching of green sheets. In view of these problems, the present applicant proposed an improvement over the above problems in the specification of Japanese Patent Application No. 44094/1983. The present invention further improves this by including an acrylic acid moiety and an acrylamide moiety in the molecule.
本発明者らは上記問題点につき種々の検討を行なった結
果、バインダーとして特定の樹脂を用いることによって
解決できることを見い出した。The present inventors conducted various studies regarding the above-mentioned problems, and as a result, discovered that the problems could be solved by using a specific resin as the binder.
本発明の目的は平均粒径１μ口以下の微細なセラミック
粉を用いても良好なセラミック成形体を得るに適した成
形用バインダーを提供することにある。An object of the present invention is to provide a molding binder suitable for obtaining a good ceramic molded body even when using fine ceramic powder with an average particle size of 1 μm or less.
すなわち本発明は ＣＨ，。That is, the present invention CH.
〔但し、ｊ＝１〜１５、ｋ＝１ ２〜３０、ｍ＝０．１
〜５、ｍ＝０．１〜５、ｎ＝ １ ００− （ｊ −）
−に＋ｌ ＋ｍ＋ｎ ）、Ｒは水素又は炭素数１〜３の
直鎖状飽邪炭化水素である。〕のくり返し単位からなる
重量平均分子量１〜２０万の酢酸ビニル−アクリルアミ
ド共重合体ケン化物のアセタール化物金主成分とするセ
ラミック粉体成形用バインダーである。[However, j = 1 to 15, k = 1 2 to 30, m = 0.1
~5, m=0.1~5, n=1 00- (j-)
- to +l +m+n), R is hydrogen or a linear saturated hydrocarbon having 1 to 3 carbon atoms. This is a binder for molding ceramic powder, which is an acetal of a saponified vinyl acetate-acrylamide copolymer having a weight average molecular weight of 1 to 200,000 and consisting of repeating units of ], and whose main component is gold.
本発明で重量平均分子量が２０万を越えるとスラリー粘
度が著しく高くなり分散性塗布適正が著しく低下する。In the present invention, when the weight average molecular weight exceeds 200,000, the viscosity of the slurry becomes extremely high and the suitability for dispersion and coating is significantly reduced.
反対に重量平均分子量が１万未満ではグリーン・シート
に割れや亀裂が入り、強度、弾力性等が著しく低下する
。On the other hand, if the weight average molecular weight is less than 10,000, the green sheet will crack or crack, and its strength, elasticity, etc. will be significantly reduced.
本発明バインダーの主成分である酢酸ビニルアクリルア
ミド共重合体のケン化物のアセタール化物において、ビ
ニルアセタール部分のＲは水素原子ま九は炭素数１〜３
の飽和炭化水素であり、將に炭素数３が好まし込が、こ
れらの２種以上を混合してもよい。In the acetalized product of the saponified product of vinyl acetate acrylamide copolymer, which is the main component of the binder of the present invention, R in the vinyl acetal moiety is a hydrogen atom, and nine carbon atoms are 1 to 3.
It is a saturated hydrocarbon, preferably having 3 carbon atoms, but two or more of these may be mixed.
ビニルアルコール部分はことごとくアセタール化するこ
とはできず１２モル慢未満では反応が進みに＜＜、３０
モル係を越えると有機溶剤に対する溶解性が低下し実用
的でない。The vinyl alcohol moiety cannot be completely acetalized, and if the mole is less than 12 molar, the reaction will not proceed.<<, 30
If the molar ratio is exceeded, the solubility in organic solvents decreases, making it impractical.
残存ビニルアセテート部分が１．０モルチ未満では、グ
リーン・シートが硬くなるため可塑剤を大量に使用する
必要がある。このためバインダー自身の接着力の低下を
招く恐れがあり強度低下をもたらし好ましく々い。ビニ
ルアセテート部分が１５モル慢を越えるとポリマーが柔
軟すぎることや、熱安定性が悪いことなどの欠点が出る
。If the residual vinyl acetate portion is less than 1.0 molt, the green sheet becomes hard and it is necessary to use a large amount of plasticizer. This may lead to a decrease in the adhesive strength of the binder itself, which is undesirable since it leads to a decrease in strength. If the vinyl acetate moiety exceeds 15 molar ratios, disadvantages such as the polymer being too flexible and poor thermal stability will occur.
アクリルアミド部分又はアクリル酸部分が５モルチを越
えるとポリマーの溶解性が悪くなり、セラミック粉の分
散が悪くグリーン・シートの物性が低下する。アクリル
酸部分が０．１モルチ未満では１μｍ以下の微細なセラ
ミック粉に対して分散が悪く良好な成形体を得ることが
できない。If the acrylamide moiety or acrylic acid moiety exceeds 5 moles, the solubility of the polymer will be poor, the dispersion of the ceramic powder will be poor, and the physical properties of the green sheet will be degraded. If the acrylic acid moiety is less than 0.1 molar, fine ceramic powder of 1 μm or less is poorly dispersed, making it impossible to obtain a good molded body.
次に、本発明のバインダーの主成分を製造する一般的方
法を説明する。酢酸ビニル−アクリルアミド共重合体の
重合は通常行なわれる溶液重合法、懸濁重合法、塊状重
合、いずれの方法でも実施できるが、製造の容易さを考
慮すると溶液重合が好ましい。この方法は適当な重合溶
媒中に酢酸ビニルを所定量仕込み重合開始剤を添加して
加温すればよい。ここでアクリルアミドは重合の進行に
伴ない分割分添するか、連続分添する方法等が挙げられ
るが均一組成の共重合体を得るためにに連続分添したほ
うがよい。次に、このようにして得られ念共重合体溶液
から該共重合体ケン化物のアセタール化物を得る方法と
しては、公知の方法で該共重合体溶液をケン化した後、
さらに酸触媒の存在下アルデヒドと反応させる二段で行
なう方法と該共重合体を酸触媒の存在下にアルデヒドと
反応させ、ケン化とアセタール化を一段で行なう方法等
任意の方法で製造可能であるが、特に好ましいのは前者
の方法であり、より具体的には該共重合体溶液にアルカ
リ金属の水酸化物等を加えケン化して該共重合体ケン化
物を得る。さらに該共重合体ケン化物を水に溶解させる
か、メタノール、エタノールなどのアルコール系の溶媒
中に分散させた後塩酸や硫酸などの酸触媒存在下にアル
デヒドを一括しであるいは少量づつ又は段階的に添加し
て所定のアセタール化度に達した時点で中和剤を添加し
反応を中止させる。中和剤とじてに、モノエタノールア
ミン、ジェタノールアミン等のアミン化合物の他アルカ
リ金属、アルカリ土類金属等の水酸化物等が使用される
が、セラミック成形時の電気特性に及ぼす影響等を考慮
してアミン化合物が用いられる。Next, a general method for producing the main component of the binder of the present invention will be explained. The vinyl acetate-acrylamide copolymer can be polymerized by any of the commonly used methods such as solution polymerization, suspension polymerization, and bulk polymerization, but solution polymerization is preferred in view of ease of production. In this method, a predetermined amount of vinyl acetate is placed in a suitable polymerization solvent, a polymerization initiator is added, and the mixture is heated. Here, acrylamide can be added in portions as the polymerization progresses, or added in continuous portions, but it is better to add acrylamide continuously in order to obtain a copolymer with a uniform composition. Next, as a method for obtaining the acetalized product of the saponified copolymer from the thus obtained telecopolymer solution, after saponifying the copolymer solution by a known method,
Furthermore, it can be produced by any method such as a two-step method in which the copolymer is reacted with an aldehyde in the presence of an acid catalyst, and a method in which saponification and acetalization are performed in one step by reacting the copolymer with an aldehyde in the presence of an acid catalyst. However, the former method is particularly preferred, and more specifically, an alkali metal hydroxide or the like is added to the copolymer solution and saponified to obtain a saponified copolymer. Furthermore, after dissolving the saponified copolymer in water or dispersing it in an alcoholic solvent such as methanol or ethanol, the aldehyde is added all at once or in small amounts or stepwise in the presence of an acid catalyst such as hydrochloric acid or sulfuric acid. When a predetermined degree of acetalization is reached, a neutralizing agent is added to stop the reaction. As neutralizing agents, amine compounds such as monoethanolamine and jetanolamine, as well as hydroxides of alkali metals and alkaline earth metals, etc., are used. Amine compounds are used with consideration.
本発明ではアクリル酸部分とアクリルアミド部分を併用
することによりグリーン・シート物性を向上させること
ができる。In the present invention, the physical properties of the green sheet can be improved by using the acrylic acid moiety and the acrylamide moiety together.
本発明で使用するセラミック微粉とじてに特に制限はな
く、公知のセラミック微粉、例えばアルミナ、窒化アル
ミ、窒化珪素、炭化珪素、ジルコニア、チタン酸バリウ
ム、ベリリア等の１種又は２種以上が挙げられる。その
平均粒子径としては、通常使用されている１μｍ以上の
セラミック粉は勿論平均粒径１μｍ以下の微粉でも構わ
ない。The ceramic fine powder used in the present invention is not particularly limited, and examples include one or more known ceramic fine powders such as alumina, aluminum nitride, silicon nitride, silicon carbide, zirconia, barium titanate, and beryllia. . As for the average particle size, not only the commonly used ceramic powder with an average particle size of 1 μm or more, but also fine powder with an average particle size of 1 μm or less may be used.
セラミックシートを製造する配合としては重量割合でセ
ラミック粉１００部に対し、ポリビニルアセタール５〜
１２部、溶剤３０〜８０部が好ましい。溶剤としてはメ
タノール、エタノール、エタノール等のアルコール類及
ヒドルエン、キシレン等の芳香族炭化水素類、アセトン
、メチルエチルケトン等のケトン類、トリクロロエチレ
ン、テトラクロロエチレン等の塩素系溶剤等がちり、こ
れらを加工条件に適合させて混合溶剤として使用する。The composition for producing ceramic sheets is 5 to 5 parts of polyvinyl acetal per 100 parts of ceramic powder by weight.
12 parts and 30 to 80 parts of solvent are preferred. Solvents include alcohols such as methanol, ethanol, and ethanol, aromatic hydrocarbons such as hydrene and xylene, ketones such as acetone and methyl ethyl ketone, and chlorinated solvents such as trichlorethylene and tetrachloroethylene, which are compatible with the processing conditions. and use it as a mixed solvent.
以下実施例及び比較例を挙げて本発明を具体的に説明す
るが、本発明はこれらに限定されるものではない。尚例
中の部及び優は重量基準である。The present invention will be specifically explained below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In addition, parts and units in the examples are based on weight.
攪拌機、還流冷却器、滴下装置および温度針をつけた反
応器内にメタノール２５００部、酢酸ビニル７５００部
、重合開始剤としてα、ｄ−アゾビスイソデチロニトリ
ル０．０３部を投入する。窒素気流下に系内金攪拌しな
がら温度を上昇させ、重合が開始した時点からアクリル
アミド５部を連続的に添加し、系内の固形分濃度が５０
％になる時点で添加を終了させる。この共１合体溶液に
含まれる未反応のモノマーを除去し酢酸ビニル−アクリ
ルアミド共重合体のメタノール溶液を得几。2,500 parts of methanol, 7,500 parts of vinyl acetate, and 0.03 part of α, d-azobisisodethyronitrile as a polymerization initiator are charged into a reactor equipped with a stirrer, a reflux condenser, a dropping device, and a temperature needle. The temperature was raised while stirring the metal in the system under a nitrogen stream, and 5 parts of acrylamide was continuously added from the time polymerization started, until the solid concentration in the system reached 50%.
%, the addition is stopped. Unreacted monomers contained in this copolymer solution were removed to obtain a methanol solution of vinyl acetate-acrylamide copolymer.
次に、該共重合体溶液の共重合体濃度をメタノールで２
５優に調整し九溶液６０００部を４０℃に保ち、攪拌下
、水酸化ナトリウム４１．９部を含むメタノール溶液を
加えるとケン化物が析出し友。Next, the copolymer concentration of the copolymer solution was adjusted to 2 with methanol.
When 6,000 parts of the solution was adjusted to 50% and kept at 40°C, and a methanol solution containing 41.9 parts of sodium hydroxide was added while stirring, saponified products precipitated.
これを粉砕・洗浄後、８０°Ｃ気流中で乾燥して７５０
部の白色粉末状の重合体を得た。After crushing and washing, dry it in an air stream at 80°C to 750°C.
A white powdery polymer was obtained.
次に、攪拌機、還流冷却器及び温度計をつげた反応器内
にメタノール４７０部、３５ｅｌＩ塩酸１０部を仕込み
さらに、該ＰＶＡ系重合体１００部を攪拌しながら添加
した。次いでこれにプチルアルデμド１４０部を添加し
、温度６５°Ｃで６時間反応させた。反応終了後冷却し
、水酸化ナトリウム４部を添加し中和した。これを水よ
り析出させ、水洗・乾燥レポリビニルアセタール（１）
ｌｌ九。Next, 470 parts of methanol and 10 parts of 35elI hydrochloric acid were placed in a reactor equipped with a stirrer, a reflux condenser, and a thermometer, and then 100 parts of the PVA polymer was added with stirring. Next, 140 parts of butyralde was added to this, and the mixture was reacted at a temperature of 65°C for 6 hours. After the reaction was completed, the mixture was cooled and neutralized by adding 4 parts of sodium hydroxide. This is precipitated from water, washed with water and dried.Repolyvinyl acetal (1)
ll9.
このポリビニルアセタール（Ｉ）を分析した結果ｊ＝１
．０モルチ、ｋ＝２９．５モル優、１＝０−１モル優、
ｍ＝２．３モル優、ｎ＝６７．１モル優となり重量平均
分子量は１９．７万であった。As a result of analyzing this polyvinyl acetal (I), j=1
．． 0 mol, k=29.5 mol, 1=0-1 mol,
m=2.3 moles or more, n=67.1 moles or more, and the weight average molecular weight was 197,000.
前述の合成方法を基に、重合時のモノマー量、モノマー
と溶剤比率及び１合開始剤量を種々調節し酢酸ビニル−
アクリルアミド共重合体を得た。Based on the above-mentioned synthesis method, the amount of monomer during polymerization, the ratio of monomer to solvent, and the amount of 1-initiator were variously adjusted to produce vinyl acetate.
An acrylamide copolymer was obtained.
該共重合体を種々の条件でケン化及びアセタール化を行
ない表記載のポリビニルアセタール■〜■を製造した。The copolymer was saponified and acetalized under various conditions to produce polyvinyl acetals 1 to 2 listed in the table.
特性を表に示す。The characteristics are shown in the table.
また、ポリビニルアセタール（Ｉ〜■）をセラミックバ
インダーとしてグリーン・シートを作成し、物性を調べ
九結果を表に示した。表中のＰａｌ、Ａａｌｄ 、
Ｂａ１ｄはそれぞれホルムアルデヒド、アセトアルデヒ
ド、ブチルアルデヒドを示す。In addition, green sheets were prepared using polyvinyl acetal (I to ■) as a ceramic binder, and their physical properties were investigated and the results are shown in the table. Pal, Aald in the table,
Ba1d represents formaldehyde, acetaldehyde, and butyraldehyde, respectively.
グリーン・シートの作成方法
ポリ−ニルアセテート２部及びソルビタントリオレート
０．２５部とをエタノール／トリクロロエチレン（４０
／６０）４０部に溶解し、アルミナ（口軽化工品： ｔ
ｓ−２３（平均粒径Ｑ、６沌））１００部と共にな・−
ルミルに入れ２０時間混合粉砕後、後練りとしてフタル
酸ジプチル５部及び残りのポリビニルアセタール８部を
上記溶剤と同組成の溶剤４０部に溶解後、ポットに加え
２０時間混合してからスラリーを取り出して、脱泡・濃
縮した。これをドクターデレーばでポリエチレンテレフ
タレートフィルム上に膜厚１．２Ｂに塗布し、室温で４
時間礼譲後２０℃／Ｈｒの昇温速度で１２０℃まで昇温
し、１２０℃で１時間乾探してグリーン・シートを得た
。Method for making green sheet: 2 parts of poly-nylacetate and 0.25 part of sorbitan triolate are mixed with ethanol/trichlorethylene (40
/60) Dissolved in 40 parts, alumina (light-weighted product: t
With 100 parts of s-23 (average particle size Q, 6 chaos)
After mixing and pulverizing in Lumil for 20 hours, dissolve 5 parts of diptyl phthalate and the remaining 8 parts of polyvinyl acetal in 40 parts of a solvent with the same composition as the above solvent, add to the pot and mix for 20 hours, then take out the slurry. The mixture was defoamed and concentrated. This was applied to a film thickness of 1.2B on a polyethylene terephthalate film using a Dr. Delley coater, and the film was coated at room temperature for 4 hours.
After giving time, the temperature was raised to 120°C at a temperature increase rate of 20°C/Hr, and a green sheet was obtained by drying at 120°C for 1 hour.
測定法
ポリマー組成
Ｏビニルアルコール部分はＪ工５Ｋ−６７２８ポリビニ
ルデチラール試験方法（５，５，２）によった。Measuring method Polymer composition O Vinyl alcohol portion was determined according to J Engineering 5K-6728 Polyvinyl Decyral Test Method (5, 5, 2).
ｏｅビニルアセテート部分アクリルアミド部分及びアク
リル酸部分の和はｓｘｅ ｘ −６７２８の５．５．１
に記載の方法で行ないアルカリの消費量からＣ〕、１
＋［ｂ ＋ （）ｍの重量％を求めた。The sum of the oe vinyl acetate part, the acrylamide part, and the acrylic acid part is 5.5.1 of sxe x-6728.
C], 1 from the amount of alkali consumed using the method described in
The weight percent of +[b + ()m was determined.
Ｏビニルアセテート部分のみの定＋ｉは強アルカリ中で
エステル結合を切断し、中和後ガスクロマトグラフィー
法によジ遊離の酢ｒＲｔ一定量して求めた。The constant +i of only the O-vinyl acetate portion was determined by cleaving the ester bond in a strong alkali, neutralizing it, and then adding a fixed amount of di-free vinegar rRt by gas chromatography.
０ アクリルアミド部分はＪ工１３に−０１０２の４４
有機体窒素測定法によった。0 Acrylamide part is 44 of -0102 to J Engineering 13
Based on organic nitrogen measurement method.
Ｏアクリル酸部分は上記の績果から計算により求めた。The O acrylic acid moiety was calculated from the above results.
０ ビニル７ セタ−ル部分はＣ）ｎ／、＝ １００−
（Ｃ）＋＋（ｈ＋（ｈ＋（：１ｍ）として重量慢を求め
た。0 Vinyl 7 Cetal moiety is C) n/, = 100-
(C)++(h+(h+(:1m)).
以上の姑果より各組成の重量壬を求めモルチに計算し直
してｊｔ ｋ、 １．ｍ、ｎを求め次。Calculate the weight of each composition from the above results and recalculate it to molch, jt k, 1. Find m and n and then.
重量平均分子量 次の条件により九。Weight average molecular weight (9) subject to the following conditions.
機 種：東洋曹達製ＨＬＣ８０２Ａ／Ｓ検出器：Ｒエ
カラム： ＧＭＨ６２本流 量： １．Ｑｍｌ１分
、圧 カニ６９ｋｇ／ａｒｅ’注入量：５００μｔ ＃
ｋ 度二〇、１チ溶 剤ＣＴＨＥＮ カラム温
度：３８°Ｃグリーン・シートの物性
Ｏ引張試験；グリーン・シートのキャスティング方向に
平行に幅１ｃｒＩＬ長さ５のに切断したシートをテンシ
ロンで測定し単位面積当りの引張強度で示した。Model: Toyo Soda HLC802A/S Detector: R
Column: GMH62 main flow rate: 1. Qml 1 minute, pressure crab 69kg/are' injection amount: 500μt #
K degree 20, 1 degree Solvent CTHEN Column temperature: 38°C Physical properties of green sheet O Tensile test: A sheet cut parallel to the casting direction of the green sheet to a width of 1crIL and length of 5 is measured using a tensilon unit. It is expressed as tensile strength per area.
０ シート密度二見掛比！（ｇ／ｃｒＩＬ３）グリーン
シートのキレン、ノビ、モロサの判定基準
◎：特に良好
Ｏ：良好
Δ：やや不良
×：不良（使用不可）
なお各判定項目における不良の状態を以下に示す。0 Sheet density two-apparent ratio! (g/crIL3) Judgment criteria for green sheet loss, cracking, and morosa ◎: Particularly good O: Good Δ: Slightly poor ×: Poor (unusable) The defect status for each judgment item is shown below.
キレン不良ニゲリーンシートのひび割れの著しい状態
ノビ不良 ニゲリーンシートが極めて柔軟であり、製造
時の打抜きによる伸びを
生ずる状態
モロサネ良ニゲリーン・シート巻取り時に折れや亀裂を
生ずる状態
〔発明の効果〕
本発明のバインダーは従来キレンのないグＩＪ−ン・シ
ートの製造が難しかった平均粒径１μｍ以下の微細なセ
ラミック粉について特に有効である。A condition in which the Nigeleen sheet is severely cracked. A condition in which the Nigeleen sheet is extremely flexible and stretches due to punching during manufacturing. A condition in which folds or cracks occur when the Nigeleen sheet is rolled up. [Effects of the invention] Book The binder of the invention is particularly effective for fine ceramic powders with an average particle size of 1 .mu.m or less, for which it has been difficult to produce glass IJ sheets without cracking.
即ち従来のパンダーより添加量が少くてセラミック粉の
グリーンシート強度が高くなるので、薄く密度の高いセ
ラミックシートが得られる。That is, the amount added is smaller than that of conventional panders, and the strength of the green sheet of ceramic powder is increased, so that a thin and dense ceramic sheet can be obtained.
特許出願人 電気化学工業株式会社
手続補正書
昭和６１年１２月１６日
特許庁長官 黒 １）明 ′ｊＩＡ 殿１、事件の
表示
昭和６１年特許願第２６８＜５８１号
２、発明の名称
セラミック粉体成形用バインダー
６、補正をする者
事件との関係 特許出願人
住所 ■１００ 東京都千代田区有楽町１丁目４番１
号明細書の特許請求の範囲の欄及び発明の詳細な説明の
欄
５、１！正の内容
１）第１頁特許請求の範囲を別紙のとおり訂正する。Patent Applicant Denki Kagaku Kogyo Co., Ltd. Procedural Amendment December 16, 1985 Commissioner of the Patent Office Kuro 1) Ming 'jIA 1, Indication of Case 1985 Patent Application No. 268<581 2, Name of Invention Ceramic Powder Body molding binder 6, relationship with the amended case Patent applicant address ■100 1-4-1 Yurakucho, Chiyoda-ku, Tokyo
Claims column and Detailed description of the invention column 5, 1! Correct content 1) The claims on page 1 are corrected as shown in the attached sheet.
２）第５頁第４行の［＋ ｌ ＋ ｍ ＋ ｎ ） Ｊ
’ｅ ｒ＋ｌ＋ｍ）Ｊと訂正する。2) [+ l + m + n) J on page 5, line 4
'e r+l+m) Correct it as J.
６）第１１頁第１４行のｒ Ｐａ１ｄ Ｊ ｔ ｒ Ｆ
ａｌｄ 、Ｊと訂正する。6) r Pa1d J t r F on page 11, line 14
ald, correct J.
４）第１６頁、表の第９段「Ｐａ１ｄ ／ Ｂａ１ｄ
Ｊ ＠ｒ Ｆａｌｄ ／ Ｂａ１ｄ Ｊと訂正する。4) Page 16, column 9 of the table “Pa1d / Ba1d
Correct it as J @r Fald / Bald J.
別紙 特許請求の範囲 ＣＨ３゜ ■Attachment Scope of claims CH3゜ ■
Claims (1)
５、ｍ＝０．１〜５、ｎ＝１００−（ｊ＋ｋ＋ｌ＋ｍ＋
ｎ）、Ｒは水素又は炭素数１〜３の直鎖状飽和炭化水素
である。〕のくり返し単位からなる重量平均分子量１〜
２０万の酢酸ビニル−アクリルアミド共重合体ケン化物
のアセタール化物を主成分とするセラミック粉体成形用
バインダー。[Claims] (A) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (B) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (C) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (D) ▲ Mathematical formulas , chemical formulas, tables, etc. ▼ and (E) ▲ Numerical formulas, chemical formulas, tables, etc. ▼ [However, j = 1 ~ 15, k = 12 ~ 30, l = 0.1 ~
5, m=0.1~5, n=100-(j+k+l+m+
n), R is hydrogen or a linear saturated hydrocarbon having 1 to 3 carbon atoms. ] weight average molecular weight consisting of repeating units of 1~
A binder for ceramic powder molding whose main component is an acetalized product of a saponified vinyl acetate-acrylamide copolymer of 200,000.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61268681A JPS63123858A (en) | 1986-11-13 | 1986-11-13 | Binder for forming ceramic powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61268681A JPS63123858A (en) | 1986-11-13 | 1986-11-13 | Binder for forming ceramic powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63123858A true JPS63123858A (en) | 1988-05-27 |
Family
ID=17461914
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61268681A Pending JPS63123858A (en) | 1986-11-13 | 1986-11-13 | Binder for forming ceramic powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63123858A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5925491A (en) * | 1996-10-25 | 1999-07-20 | Kodak Polychrome Graphics Llc | Amido substituted acetal polymer binders and their use in photosensitive compositions |
| WO2001067179A3 (en) * | 2000-03-09 | 2002-01-17 | Clariant Gmbh | Use of carboxyl group-containing acetal polymers in light-sensitive compositions and lithographic printing plates |
| JP2010001488A (en) * | 2003-01-23 | 2010-01-07 | Kuraray Co Ltd | Binder for ceramic forming comprising vinyl acetal polymer and ceramic green sheet containing the same |
-
1986
- 1986-11-13 JP JP61268681A patent/JPS63123858A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5925491A (en) * | 1996-10-25 | 1999-07-20 | Kodak Polychrome Graphics Llc | Amido substituted acetal polymer binders and their use in photosensitive compositions |
| WO2001067179A3 (en) * | 2000-03-09 | 2002-01-17 | Clariant Gmbh | Use of carboxyl group-containing acetal polymers in light-sensitive compositions and lithographic printing plates |
| US6808858B2 (en) | 2000-03-09 | 2004-10-26 | Kodak Polychrome Graphics Llc | Use of carboxyl group-containing acetal polymers in light-sensitive compositions and lithographic printing plates |
| JP2010001488A (en) * | 2003-01-23 | 2010-01-07 | Kuraray Co Ltd | Binder for ceramic forming comprising vinyl acetal polymer and ceramic green sheet containing the same |
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