Tape casting slurry, green porcelain tape material and preparation method thereof

Abstract

The present application is applicable to the field of electronic material technology, and provides a tape casting slurry, a raw porcelain tape material and a preparation method thereof, wherein the tape casting slurry method comprises: according to mass percentage, 10-50% solvent, 1-2% dispersant, 40-80% porcelain powder, 3-10% sintering aid, 1-10% plasticizer, 5-15% binder and 1-3% tackifier; wherein the tackifier comprises a tackifying resin. The present application provides a tape casting slurry that can take into account both the sintering density and the fracture strength of the porcelain body and improve the interlayer bonding of the ceramic raw porcelain tape.

Description

Technical Field

[0001] The present application belongs to the technical field of electronic materials, and in particular relates to a tape casting slurry, a green porcelain tape material and a preparation method thereof. Background Art

[0002] With the rapid development of the electronic information technology industry, electronic products are developing towards miniaturization, multifunctionality, and high integration. As the core of electronic information technology, microelectronic packaging technology plays an extremely important role. The miniaturization and high integration of packaging means that the load value per unit area of ​​the packaging shell is getting larger and larger, and at the same time, it also puts forward higher requirements on the fracture strength of ceramic materials.

[0003] It is true that reducing the particle size of ceramic powder can increase the sintering density and fracture strength of the ceramic body, but the reduction of powder particle size will inevitably lead to a decrease in the mechanical bite force between the layers of ceramic green tape, thereby causing the bonding between the layers to deteriorate.

[0004] The prior art improves the bonding between layers by printing transition layers between raw porcelain tape layers, which not only increases the production process and production costs, but also causes problems such as extrusion deformation of the raw porcelain.

[0005] Therefore, there is an urgent need for a tape casting material that can take into account both the sintering density and the fracture strength of the porcelain body and improve the bonding of the ceramic green tape layer. Summary of the invention

[0006] In order to overcome the problems existing in the related technology, the embodiments of the present application provide a tape casting slurry, a green porcelain tape material and a preparation method thereof. The tape casting slurry not only takes into account the sintering density and the fracture strength of the porcelain body, but also improves the bonding between the layers of the ceramic green porcelain tape.

[0007] This application is implemented through the following technical solutions:

[0008] In the first aspect, an embodiment of the present application provides a casting slurry, which includes, in terms of mass percentage, 10-50% solvent, 1-2% dispersant, 40-80% porcelain powder, 3-10% sintering aid, 1-10% plasticizer, 5-15% binder and 1-3% tackifier; wherein the tackifier includes a tackifying resin.

[0009] The present application adopts a tackifying resin to increase the viscosity and fluidity of the base resin in the binder during the hot pressing process, especially under low hot pressing parameters, so that the interlayer bonding of the raw porcelain sheets can be achieved, and the prepared raw porcelain tape has excellent performance, especially the bonding surfaces between multiple raw porcelain sheets are complete, without defects such as stratification and cracks.

[0010] Preferably, the tackifying resin comprises styrene-methyl methacrylate oligomer.

[0011] In a possible implementation manner of the first aspect, the ceramic powder includes alumina powder, the alumina content of the alumina powder is 99%, and the particle size is 0.5 to 2.0 μm.

[0012] In a possible implementation of the first aspect, the solvent includes a binary solvent consisting of any two of anhydrous ethanol, n-butanol, isopropanol, methoxypropanol, ethoxypropanol, diacetone alcohol, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, cyclohexanone, butanone, methyl isobutyl ketone, dichloromethane, chloroform or toluene. The dispersant includes one or more of sodium oleate, carboxylates, sulfate ester salts, sulfonates, alkyl aryl phosphates, alkyl benzene sulfonates, phosphate ester salt-type polymers, polycaprolactone polyol-polyethyleneimine block copolymer-type dispersants, acrylate polymer-type dispersants, polyurethane or polyester polymer dispersants, and maleic anhydride copolymers. The sintering aid includes one or more of MgO, CaO, SiO2, TiO, MoO, Gr2O3, Fe2O3, MnO2, CaCO3, TiO2, La2O3, Y2O3, Nd2O3, CeO2, CoO, NiO, B2O3, and kaolin. The plasticizer includes one or more of dibutyl phthalate, dioctyl phthalate, butyl benzyl phthalate, polyethylene glycol, dialkyl adipate, dialkyl sebacate, trialkyl phosphate, trialkyl phosphite, dibutyl phthalate, and acrylic acid carbonate. The binder includes polyvinyl butyral.

[0013] The embodiment of the present application increases the mutual adhesion of the binder at the bonding surface of the green ceramic tape by introducing a tackifying resin into the tape casting slurry. The reason why the tackifying resin can increase the bonding between the layers of the tape casting green body is that, on the one hand, the tackifying resin can slow down the interaction between the matrix resin and the ceramic powder, thereby enhancing the adhesion of the matrix resin itself during hot pressing; on the other hand, the tackifying resin has low viscosity and good miscibility with the binder. In the slurry, adding a low molecular weight tackifying resin is beneficial to the movement of the molecular chain of the matrix resin and increases the fluidity of the matrix resin during hot pressing. Therefore, the mutual adhesion of the binder between the layers during hot pressing is greater, and the bonding is tighter.

[0014] In a second aspect, an embodiment of the present application provides a green porcelain tape material prepared from the tape casting slurry described in any one of the first aspects.

[0015] In the third aspect, the embodiment of the present application provides a method for preparing a green porcelain tape, which is used to prepare the green porcelain tape described in the second aspect, specifically comprising: mixing a solvent, a dispersant, a porcelain powder and a sintering aid in percentage by mass, and performing a ball milling once to obtain a basic slurry; adding a plasticizer, a binder and a viscosity enhancer in percentage by mass to the base slurry, mixing the mixture, and performing a second ball milling to obtain a tape-casting slurry; vacuum degassing and tape-casting the tape-casting slurry to form a green porcelain sheet having a thickness of 0.05 to 0.5 mm; and hot pressing and laminating at least two layers of green porcelain sheets to obtain a high-strength ceramic green porcelain tape.

[0016] Preferably, the rotation speed of the first ball mill is 20-40 rpm, and the duration is 24-48 h; the rotation speed of the second ball mill is 20-40 rpm, and the duration is 24-48 h.

[0017] Preferably, the vacuum degree of vacuum degassing is 0.05MPa-0.095MPa; the casting belt speed of tape casting is 0.1-0.8m / min, and the casting temperature is 0-90°C.

[0018] Preferably, the temperature of hot pressing lamination is 30-60° C., the pressure is 1 MPa-5 MPa, and the holding time is 2-8 min.

[0019] In a fourth aspect, an embodiment of the present application provides a high-strength ceramic, comprising a tape-casting slurry as described in any one of the first aspects as a raw material, or a green porcelain tape as described in the second aspect as a raw material, or a green porcelain tape prepared by the green porcelain tape preparation method as described in the third aspect as a raw material.

[0020] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 This is a cross-sectional view of a green porcelain strip material after hot pressing into which 10 g of tackifying resin is introduced, provided in one embodiment of the present application;

[0023] Figure 2 This is a cross-sectional view of a green porcelain strip material after hot pressing into which an additional 10 g of matrix resin is introduced, provided in one embodiment of the present application;

[0024] Figure 3is a cross-sectional view of another green porcelain strip material after hot pressing without introducing a tackifying resin provided in an embodiment of the present application;

[0025] Figure 4 This is a cross-sectional view of another green porcelain strip after hot pressing into which an additional 10 g of plasticizer is introduced, provided in one embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of this application clearer, the present application is described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the described embodiments are only part of the embodiments of this application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0027] The present application provides a casting slurry, which may include, by mass percentage:

[0028] Solvent 10-50%, dispersant 1-2%, porcelain powder 40-80%, sintering aid 3-10%, plasticizer 1-10%, binder 5-15% and tackifier 1-3%;

[0029] It should be noted that the tackifier includes a tackifying resin. The tackifying resin can increase the viscosity and fluidity of the base resin in the binder during the hot pressing process, especially under low hot pressing parameters, so that the interlayer bonding of the green porcelain sheets can be achieved, and the green porcelain tape material produced has excellent performance, especially the bonding surface between multiple green porcelain sheets is complete without defects such as delamination and cracks.

[0030] Preferably, the tackifying resin comprises styrene-methyl methacrylate oligomer.

[0031] Optionally, the ceramic powder includes one or more of alumina powder, silica powder, calcium oxide powder and magnesium oxide powder.

[0032] Preferably, the ceramic powder is alumina powder, wherein the alumina content of the alumina powder is 99% and the particle size is 0.5 to 2.0 μm.

[0033] In some embodiments, the solvent includes a binary solvent consisting of any two of anhydrous ethanol, n-butanol, isopropanol, methoxypropanol, ethoxypropanol, diacetone alcohol, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, cyclohexanone, butanone, methyl isobutyl ketone, dichloromethane, chloroform or toluene.

[0034] In some embodiments, the dispersant includes one or more of sodium oleate, carboxylates, sulfates, sulfonates, alkyl aryl phosphates, alkyl benzene sulfonates, phosphate-type polymers, polycaprolactone polyol-polyethyleneimine block copolymer-type dispersants, acrylate polymer dispersants, polyurethane or polyester polymer dispersants, and maleic anhydride copolymers.

[0035] In some embodiments, the sintering aid includes one or more of MgO, CaO, SiO2, TiO, MoO, Gr2O3, Fe2O3, MnO2, CaCO3, TiO2, La2O3, Y2O3, Nd2O3, CeO2, CoO, NiO, B2O3, and kaolin.

[0036] In some embodiments, the plasticizer includes one or more of dibutyl phthalate, dioctyl phthalate, butyl benzyl phthalate, polyethylene glycol, dialkyl adipate, dialkyl sebacate, trialkyl phosphate, trialkyl phosphite, dibutyl phthalate, and acrylic acid carbonate.

[0037] In some embodiments, the binder includes polyvinyl butyral.

[0038] The embodiment of the present application increases the mutual adhesion of the binder at the bonding surface of the green ceramic tape by introducing a tackifying resin into the tape casting slurry. The reason why the tackifying resin can increase the bonding between the layers of the tape casting green body is that, on the one hand, the tackifying resin can slow down the interaction between the matrix resin and the ceramic powder, thereby enhancing the adhesion of the matrix resin itself during hot pressing; on the other hand, the tackifying resin has low viscosity and good miscibility with the binder. In the slurry, adding a low molecular weight tackifying resin is beneficial to the movement of the molecular chain of the matrix resin and increases the fluidity of the matrix resin during hot pressing. Therefore, the mutual adhesion of the binder between the layers during hot pressing is greater, and the bonding is tighter.

[0039] The present application provides a green porcelain tape material, which is prepared based on the tape casting slurry described above.

[0040] The present application also provides a method for preparing a green porcelain tape material, which is used to prepare a green porcelain tape material based on a tape casting slurry, and the specific steps are as follows:

[0041] The solvent, dispersant, porcelain powder and sintering aid are mixed according to mass percentage and ball milled once to obtain a basic slurry.

[0042] Plasticizer, binder and tackifier are added to the base slurry in percentage by mass, mixed, and subjected to secondary ball milling to obtain a casting slurry.

[0043] The casting slurry is subjected to vacuum degassing and casting molding to form a green porcelain sheet, wherein the thickness of the green porcelain sheet is 0.05 to 0.5 mm.

[0044] At least two layers of green ceramic sheets are laminated by hot pressing to produce green ceramic strip material of high-strength ceramic.

[0045] The method for preparing green porcelain tape provided in the embodiment of the present application comprises mixing solvent, dispersant, porcelain powder, sintering aid, plasticizer, binder and tackifier according to mass percentage, and performing ball milling twice to obtain tape casting slurry, and then manufacturing high-strength ceramic green porcelain tape through vacuum degassing, tape casting and hot pressing lamination.

[0046] The specific process of the preparation method of the raw porcelain strip material is described in detail as follows:

[0047] In some embodiments, a solvent, a dispersant, a ceramic powder and a sintering aid are put into a ball mill according to mass percentage and ball-milled once to prepare a basic slurry.

[0048] Preferably, the rotation speed of one ball milling is 20-40 rpm and the duration is 24-48 hours.

[0049] Optionally, ball milling balls may be placed in the ball milling jar to improve the ball milling effect. The ball milling balls may be zirconia balls or steel balls, etc., and this application does not further limit this.

[0050] In some embodiments, a plasticizer, a binder, and a tackifier are added to the prepared base slurry and mixed, and then ball milled for a second time to prepare a casting slurry.

[0051] Preferably, the secondary ball milling has a rotation speed of 20 to 40 rpm and a duration of 24 to 48 hours.

[0052] In some embodiments, the prepared casting slurry is subjected to vacuum degassing, wherein the vacuum degree of the vacuum degassing is 0.05 MPa to 0.095 MPa.

[0053] In some embodiments, the degassed casting slurry is subjected to tape casting to form a green ceramic sheet with a thickness of 0.05 mm to 0.5 mm.

[0054] Preferably, a 4-stage zoned temperature-controlled casting machine is used to cast the degassed casting slurry.

[0055] Furthermore, the casting belt speed of the casting machine can be 0.1-0.8 m / min, and the temperature of the first zone to the fourth zone of the drying chamber of the casting machine are all set to 0-90°C.

[0056] In some embodiments, at least two layers of green ceramic sheets are stacked and then hot pressed.

[0057] Preferably, the temperature of the hot pressing lamination is set to 30-60° C., the pressure is set to 1 MPa-5 MPa, and the holding time is set to 2-8 min.

[0058] The present application also provides a high-strength ceramic, which is made from the casting slurry disclosed in the present application as a raw material, or from the green porcelain tape disclosed in the present application as a raw material, or from the green porcelain tape prepared by the green porcelain tape preparation method provided in the present application.

[0059] In order to verify the beneficial effects of the casting slurry provided in this application, the following specific examples are provided, which are described in detail as follows:

[0060] Embodiment 1:

[0061] The first method for preparing a green porcelain tape material, in which 10 g of styrene-methyl methacrylate oligomer is used, is specifically prepared as follows:

[0062] Step 101, weigh 100 g of a mixed solvent of anhydrous ethanol and butyl acetate (volume ratio 1:1), 6.5 g of phosphate, 500 g of HTCC ceramic powder, and 50 g of a sintering aid, and ball-mill at 40 rpm for 36 hours to obtain a uniformly dispersed first-stage slurry.

[0063] Step 102: add 150 g of a mixed solvent of anhydrous ethanol and butyl acetate (volume ratio 1:1), 25 g of butyl benzyl phthalate, 50 g of polyvinyl butyral, and 10 g of styrene-methyl methacrylate oligomer, and continue ball milling at 40 rpm for 36 hours.

[0064] Step 103, the slurry obtained by ball milling is degassed in a vacuum degassing machine, and the viscosity after degassing is 15000 cps.

[0065] Step 104, casting the slurry obtained after vacuum degassing on a casting machine to obtain a green tape of high-strength ceramics.

[0066] Embodiment 2:

[0067] The second method for preparing a green porcelain tape material is to replace 10 g of styrene-methyl methacrylate oligomer with 10 g of polyvinyl butyral. The specific preparation method is as follows:

[0068] Step 201, weigh 100 g of a mixed solvent of anhydrous ethanol and butyl acetate (volume ratio 1:1), 6.5 g of phosphate, 500 g of HTCC ceramic powder, and 50 g of a sintering aid, and ball-mill at 40 rpm for 36 hours to obtain a uniformly dispersed first-stage slurry.

[0069] Step 202: Add 150 g of a mixed solvent of anhydrous ethanol and butyl acetate (volume ratio 1:1), 25 g of butyl benzyl phthalate, and 60 g of polyvinyl butyral, and continue to ball mill at 40 rpm for 36 hours.

[0070] Step 203, the slurry obtained by ball milling is degassed in a vacuum degassing machine, and the viscosity after degassing is 15000 cps.

[0071] Step 204, casting the slurry obtained after vacuum degassing on a casting machine to obtain a green tape of high-strength ceramics.

[0072] Embodiment 3:

[0073] The third method for preparing a green porcelain tape material, in which 10 g of styrene-methyl methacrylate oligomer is not added, is specifically prepared as follows:

[0074] Step 301, weigh 100 g of a mixed solvent of anhydrous ethanol and butyl acetate (volume ratio 1:1), 6.5 g of phosphate, 500 g of HTCC ceramic powder, and 50 g of a sintering aid, and ball-mill at 40 rpm for 36 hours to obtain a uniformly dispersed first-stage slurry.

[0075] Step 302: Add 150 g of a mixed solvent of anhydrous ethanol and butyl acetate (volume ratio 1:1), 25 g of butyl benzyl phthalate, and 50 g of polyvinyl butyral, and continue to ball mill at 40 rpm for 36 hours.

[0076] Step 303: Degas the slurry obtained by ball milling in a vacuum degassing machine, and the viscosity after degassing is 15000 cps.

[0077] Step 304, casting the slurry obtained after vacuum degassing on a casting machine to obtain a green tape of high-strength ceramics.

[0078] Embodiment 4:

[0079] The fourth method for preparing green porcelain tape is as follows: In the method for preparing green porcelain tape, 10 g of styrene-methyl methacrylate oligomer is replaced with 10 g of butyl benzyl phthalate. The specific preparation method is as follows:

[0080] Step 401, weigh 100 g of a mixed solvent of anhydrous ethanol and butyl acetate (volume ratio 1:1), 6.5 g of phosphate, 500 g of HTCC ceramic powder, and 50 g of a sintering aid, and ball mill at 40 rpm for 36 hours to obtain a uniformly dispersed first-stage slurry.

[0081] Step 402: Add 150 g of a mixed solvent of anhydrous ethanol and butyl acetate (volume ratio 1:1), 35 g of butyl benzyl phthalate, and 50 g of polyvinyl butyral, and continue ball milling at 40 rpm for 36 hours.

[0082] Step 403, the slurry obtained by ball milling is degassed in a vacuum degassing machine, and the viscosity after degassing is 15000 cps.

[0083] Step 404, casting the slurry obtained after vacuum degassing on a casting machine to obtain a green tape of high-strength ceramics.

[0084] In order to verify the product performance, the green porcelain tapes prepared in Examples 1, 2, 3, and 4 were randomly sampled, wherein the green porcelain tapes prepared in Examples 1 to 4 were experimental samples 1 to 4, respectively.

[0085] The four samples were laminated by hot pressing, with the number of layers being greater than 2, the lamination temperature being set at 50°C, the pressure being set at 2 MPa, and the holding time being set at 8 min.

[0086] The attached drawings 1 to 4 are electron microscope photos of the cross sections of experimental samples 1 to 4. It can be clearly seen that the layers of the green porcelain tape prepared in Example 1 have been combined into a whole, and the interface marks have completely disappeared. There is obvious stratification between the layers of the green porcelain tape prepared in Examples 2, 3, and 4.

[0087] It can be seen from the test results that: under the same conditions, the interlayer bonding of the green porcelain tape experimental sample 1 prepared by the casting slurry disclosed in this application is significantly better than that of experimental samples 2, experimental sample 3 and experimental sample 4.

[0088] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A tape casting slurry, characterized in that: The casting slurry comprises, by mass percentage: 10%~50% solvent, 1%~2% dispersant, 40%~80% porcelain powder, 3%~10% sintering aid, 1%~10% plasticizer, 5%~15% binder and 1%~3% tackifier; wherein the tackifier comprises a tackifying resin; the tackifying resin comprises styrene-methyl methacrylate oligomer; the binder comprises polyvinyl butyral; the sintering aid comprises one or more of MgO, CaO, SiO2, TiO, Cr2O3, Fe2O3, MnO2, CaCO3, TiO2, La2O3, Y2O3, Nd2O3, CeO2, CoO, NiO, B2O3 and kaolin.

2. The tape casting slurry according to claim 1, characterized in that: The ceramic powder comprises alumina powder, the alumina content of the alumina powder is 99%, and the particle size is 0.5-2.0 μm.

3. The tape casting slurry according to claim 1, characterized in that: The solvent includes a binary solvent consisting of any two of anhydrous ethanol, n-butanol, isopropanol, methoxypropanol, ethoxypropanol, diacetone alcohol, methyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, cyclohexanone, butanone, methyl isobutyl ketone, dichloromethane, chloroform or toluene; The dispersant includes one or more of sodium oleate, carboxylates, sulfate esters, sulfonates, alkyl aryl phosphates, alkyl benzene sulfonates, phosphate ester type polymers, polycaprolactone polyol-polyethyleneimine block copolymer type dispersants, acrylate polymer dispersants, polyurethane or polyester polymer dispersants, and maleic anhydride copolymers; The plasticizer includes one or more of dibutyl phthalate, dioctyl phthalate, butyl benzyl phthalate, polyethylene glycol, dialkyl adipate, dialkyl sebacate, trialkyl phosphate, trialkyl phosphite, dibutyl phthalate, and carbonated acrylic acid.

4. A raw porcelain strip material, characterized in that: The method comprises preparing the tape casting slurry based on any one of claims 1 to 3.

5. A method for preparing a raw porcelain strip, characterized in that: For preparing the green porcelain strip material as claimed in claim 4, comprising: The solvent, dispersant, porcelain powder and sintering aid are mixed according to mass percentage and ball milled once to obtain a basic slurry; Adding plasticizer, binder and tackifier in percentage by mass to the base slurry, mixing, and performing secondary ball milling to obtain a casting slurry; The casting slurry is subjected to vacuum degassing and casting to form a green porcelain sheet, wherein the green porcelain sheet has a thickness of 0.05-0.5 mm; At least two layers of the green ceramic sheets are laminated by hot pressing to obtain a high-strength ceramic green ceramic strip.

6. A method for preparing a green porcelain strip material as claimed in claim 5, characterized in that: The rotation speed of the first ball milling is 20-40 rpm, and the duration is 24-48 hours; The secondary ball milling has a rotation speed of 20-40 rpm and a duration of 24-48 h.

7. A method for preparing a green porcelain strip material as claimed in claim 5, characterized in that: The vacuum degree of the vacuum degassing is 0.05MPa~0.095Mpa; The casting belt speed of the casting molding is 0.1-0.8 m / min, and the casting temperature is 0-90° C.

8. A method for preparing a green porcelain strip material as claimed in claim 5, characterized in that: The temperature of the hot pressing lamination is 30-60° C., the pressure is 1 MPa-5 MPa, and the holding time is 2-8 min.

9. A high-strength ceramic, characterized in that: The method comprises using the tape casting slurry as described in any one of claims 1 to 3 as a raw material, or using the green porcelain tape material as described in claim 4 as a raw material, or using the green porcelain tape material prepared by the green porcelain tape material preparation method as described in any one of claims 5 to 8 as a raw material.

Images