CN1071658A

CN1071658A - Self-releasing enamel low-temp ceramics

Info

Publication number: CN1071658A
Application number: CN 91106831
Authority: CN
Inventors: 杨子初; 陈海波; 谢晓静; 冯波
Original assignee: CERAMICS INST HUNAN PROV
Current assignee: CERAMICS INST HUNAN PROV
Priority date: 1991-10-23
Filing date: 1991-10-23
Publication date: 1993-05-05
Anticipated expiration: 2006-10-23
Also published as: CN1028017C

Abstract

A kind of self-releasing enamel low-temp ceramics is made up of kaolin, wollastonite, quartz, potassium felspar sand, calcination of talc, wedding agent.The present invention all adopts natural matter, the wollastonite upgrading is used, produce high-grade household china and decorative ceramic, can save glaze processing and execute operations such as inside and outside glaze, ground-coat enamel processing, simplified the technological process of production, reduce the processing of Production of Ceramics raw material, shaping work total amount about 50% has reduced the ratio of defects of finished product.Advantages such as product has the glaze bright and clean simultaneously, and is plump full, and porcelain is fine and smooth fine and close, and production cost is lower.

Description

Self-releasing enamel low-temp ceramics

The invention belongs to a kind of self-releasing enamel low-temp ceramics of ceramic industry.

At present, the ceramic of domestic band glaze all is made up of base and glaze two portions and (is promptly executed last layer K on the inside and outside surface of green compact (porcelain body) ₂O, Na ₂O; MgO; the high glaze of basic oxide content such as CaO; then; burn till by 1320 ℃～1430 ℃ (hard-paste) temperature; the base glaze is combined; and in the smooth glassiness of surface melting formation layer of smooth; thereby play the effect that beautifies and protect goods; not only operation sequence is numerous and diverse during the ceramic glazing of this band glaze; labour intensity is big; to glaze purity; the fineness requirement strictness; and; often not tight because of glazing control, bring such as cool glaze to goods; sagging; pin hole; spot; lose glaze; many macroscopic irregularitys such as breakage directly have influence on the raising of quality product and output.People were once once wanting to solve the problems referred to above by the automation glazing technology, but were to be difficult to get a desired effect for household china, the decorative ceramic of type complexity.

Can people accomplish that ceramic does not need glazing, can and reach the effect same of glost ware? very early, many ceramists carried out unremitting research, but never find a kind of practicable, can be used for big method of producing, up to the present, the household china of complicated type, decorative ceramic remain and adopt traditional glazing technology.

Hungarian patent HuT031-036-A introduces a kind of automatic vitreous ceramic; its method is that hydrogen pure aluminium silicate (aluminium hydrosilicate) and the red soil (redmud) with 20-50% is essentially consist; add the float stone that grain size is the 10-110 micron (pumice); make the content of alkali increase 5-20%(wt%), promptly obtain ceramic product by once-firing.The whiteness of this automatic vitreous ceramic, transparence, glossiness do not reach the requirement of high-grade household china and high-grade decorative ceramic.Secondly, owing to adopted the hydrogen pure aluminium silicate industrial chemicals of 20-50% in the prescription, cause production cost higher, problems such as raw material sources difficulty.And only can be used to produce material of construction.

Russian patent Su1470-719-A, the method of introducing is to adopt the volcanic ash of 14-46%, the yellow soda ash of 4-6%, the kaolin inferior of 50-80%, under the situation of the water content of 15-17%, make alkali move to the surface by pressurization, burn till the production face brick for 950 ℃ at muffle kiln, there are three problems in this patent: the one, and must make alkali move to surface, complex process through pressurization; Two are to use industrial chemicals yellow soda ash, cost height; The 3rd, can only be used to produce the material of construction face brick.

The object of the present invention is to provide and a kind ofly can save glazing operation (account for Production of Ceramics processing, shaping work total amount about 50%), can meet or exceed the glaze effect of glazed ceramics goods again, simplify the technological process of production, reduce production costs the self-releasing enamel low-temp ceramics of save energy.

Prescription of the present invention is kaolin 10-25% by weight percentage, wollastonite 30-50%, quartzy 40-50%, potassium felspar sand 4-10%.Calcination of talc 0-2%, wedding agent 0-5%, its various raw materials acting as in prescription: kaolin one has been plastic effect in prescription, guarantees to have enough physical strengths after formed product and the green compact drying, two provide a certain amount of Al ₂O ₃(less than 10%) and wollastonite mesosilicic acid calcium CaSiO ₃Generate the Calcium of intensifiens feldspar in the time of 900～1000 ℃, wollastonite is a critical materials of the present invention, and its consumption is higher, the Al in it and the kaolin ₂O ₃2SiO ₂, the Calcium of intensifiens feldspar of Sheng Chenging is short mutually molten with small amount of potassium feldspar that adds such as 4-10% at a lower temperature, make product at a lower temperature (1220-1300 ℃) burn till, thereby, reach purpose of energy saving.Most important be potassium felspar sand and lime feldspar be lower than under 1250 ℃ molten mutually, and the fusing point of potassium felspar sand is lower than anorthitic fusing point, so, potassium felspar sand at first fusion also moves (or claiming to discharge) owing to the inside and outside temperature difference of base substrate to billet surface, after being enriched in the surface, become surface local high-content potassium felspar sand by original base substrate low levels potassium felspar sand, thereby the quartz particle on fusion surface, and with the Calcium of intensifiens feldspar (this moment temperature near 1250 ℃ of potassium felspar sands, lime feldspar begins consolute), form Watch glass layer (being the glaze layer).Al in wollastonite and the kaolin ₂O ₃2sio ₂It is cristobalite that reaction generates another composition, and it plays skeleton function with the high-content quartz that adds at base substrate, guarantees that base substrate when liquid phase generates in a large number, has enough high-temperature stabilities, is unlikely to produce distortion.Wedding agent is generally wilkinite, and its effect is the associativity that improves blank forming, thereby improves the percentage of A-class goods of moulding.The adding of calcination of talc is in order to reduce firing temperature (reducing by 20 ℃ approximately) and beneficial to thermostability.

The chemical constitution of various raw materials is in the prescription: (seeing table 1 for details)

Various feed particles fineness and cooperation thereof are to moulding, the green compact dry tenacity of product in the prescription, and the product firing temperature reaches from the generation temperature of releasing glaze, and glaze layer plumpness all has important effect.The grain composition ratio of various raw materials is: whole fineness is greater than 30 microns particle＜5%, less than 15 microns particles＞60%, less than 5 micron particle＜10%.

The technological process of production of the present invention and existing household china and decorative ceramic production technique are basic identical, but have saved glaze processing, have cancelled and have executed inside and outside glaze, ground-coat enamel treatment process.

Embodiments of the invention are: take by weighing 300 kilograms of kaolin respectively, 525 kilograms of wollastonites, quartzy 600 kilograms, 60 kilograms of potassium felspar sands, 15 kilograms of calcinated talc powders, the chemical constitution of each raw material is (seeing table 2 for details), above-mentioned raw materials is all dropped into ceramic industry with in 1.5 tonnes of ball mills, in material: ball: the ratio of water=1: 1: 0.4 is added 1500 kilograms of ball milling bodies, 400 kg of water accurately take by weighing 6 kg of water glass again and add as thinner, ball milling about 40 hours after, granularity accounts for 2.4% greater than 30 microns, account for 90.3% less than 15 microns, account for 7.3% less than 5 microns, emit with 200 mesh sieves and sieve, proportioning raw material after will processing then adopts the gypsum mould grouting moulding to make various product, burn till in 1240 ℃ of temperature of pushed bat kiln with per fltting speed that pushed away a plate in 20 minutes dry back, promptly obtains the transparency height, smooth and bright surface, glaze layer thickness reach 50～270 microns release glaze household china or decorative ceramic product certainly.

It is as follows that the present invention reaches the key technical indexes:

Transparence 55～75%, glossiness 35-60%, hardness of glaze surface 5800-6500, mechanical folding strength 170-210MPa, glaze face thickness 50-270 micron.

The present invention compares with decorative ceramic with existing household china has following characteristics:

1, can save glaze and process and execute operations such as inside and outside glaze, ground-coat enamel processing, reduce the processing of Production of Ceramics raw material, shaping work total amount about 50% has been simplified the technological process of production, and operating skill does not have particular requirement;

2, firing temperature lower (1220-1300 ℃), the firing range broad, energy-conservation obvious, be applicable to big production requirement;

3, all adopt natural matter, and the wollastonite upgrading use that will only be used to produce the face brick goods, produce high-grade household china and high-grade decorative ceramic, the glaze bright and clean, plump full, porcelain is fine and smooth fine and close, beautiful texture is good, and transparence height, oxydizing flame firing whiteness can reach more than 80 °, reducing flame burns till then to blue green, as sparkling and crystal-clear as the greenstone;

4, can reduce the work in-process breakage of product, reduce the finished product ratio of defects, split as pin hole, spot, mistake glaze, sagging, cool glaze, glaze etc.

Claims

1, a kind of self-releasing enamel low-temp ceramics is characterized in that being made up of kaolin, wollastonite, quartz, potassium felspar sand, calcination of talc, wedding agent its weight percent: kaolin 10-25%, wollastonite 30-50%, quartzy 40-50%, potassium felspar sand 4-10%, talcum 0-2%, wedding agent 0-5%.

2, pottery according to claim 1, the chemical constitution of various raw materials (seeing Table 1) in it is characterized in that filling a prescription.

3, pottery according to claim 1, the grain composition ratio of various raw materials is in it is characterized in that filling a prescription: whole fineness is greater than 30 microns particle＜5%, less than 15 microns particles＞60%, less than 5 microns particles＜10%.