CN102643084B - Composition for preparing NTC (Negative Temperature Coefficient) thermistor chip and NTC thermistor produced by same - Google Patents
Composition for preparing NTC (Negative Temperature Coefficient) thermistor chip and NTC thermistor produced by same Download PDFInfo
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- CN102643084B CN102643084B CN 201210126494 CN201210126494A CN102643084B CN 102643084 B CN102643084 B CN 102643084B CN 201210126494 CN201210126494 CN 201210126494 CN 201210126494 A CN201210126494 A CN 201210126494A CN 102643084 B CN102643084 B CN 102643084B
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Abstract
The invention discloses a composition for preparing an NTC (Negative Temperature Coefficient) thermistor chip and an NTC thermistor produced by same, belonging to the field of thermistors. The composition comprises the following components in weight: 665-670 parts of Mn3O4, 110-115 parts of Fe2O3, 16-20 parts of SiO2 and 200-205 parts of NiO, all of which are nanometer powders and have the purityof chemically pure; and chip slurry is produced by the following steps: weighing the raw materials according to the components and content thereof; uniformly mixing the raw materials and then pouring the mixture into a ball mill, adding water and subsequently grinding for 30-50 hours inside; dehydrating and drying the ground raw materials; and adding adhesives into the dried raw materials and uniformly mixing to form the chip slurry. The invention further discloses a method for preparing the NTC thermistor by using the chip slurry. Based on the invention, the service life of the resistor is prolonged and the measurement precision is improved through the adjustment of the ratio of the components in the composition for preparing an NTC thermistor chip, and therefore temperature can be rapidly measured to better meet the use requirements of high temperature equipments.
Description
Technical field
The present invention relates to the thermistor field, particularly a kind of for the composition of NTC thermistor chip and the NTC thermistor that uses the chip of said composition making.
Background technology
Thermistor is a class of senser, be divided into PTC (Positive Temperature Coefficient according to the temperature coefficient difference, positive temperature coefficient) thermistor and NTC (Negative Temperature CoeffiCient, negative temperature coefficient) thermistor.The typical feature of thermistor is to responsive to temperature, shows different resistance values under the different temperature.PTC thermistor resistance value when temperature is more high is more big, and NTC thermistor resistance value when temperature is more high is more low, and they belong to semiconductor device.
That the NTC thermistor has is highly sensitive, response speed is fast, volume is little, be easy to realize advantages such as far distance controlled and measurement, is widely used in fields such as refrigerator, air-conditioning, electric heater, integral bathroom, electronic calendar, microwave oven, barn temperature measuring, dishwasher, electric cooker, electronics toilet facility, refrigerator-freezer, soy bean milk making machine, battery of mobile phone, charger, electromagnetic oven, bread producing machine, disinfection cabinet, water dispenser, temperature control instrument, Medical Instruments, automobile thermometric, roaster, fire alarm.
In realizing process of the present invention, the inventor finds that there is following problem at least in prior art: the thermal time constant of Chang Yong NTC thermistor the slow phenomenon of temperature-sensitive in use often occurs about 7s in the market; When such thermistor is applied to high-temperature service (as large-scale water dispenser, large-scale water heater), need under hot environment, to work for a long time, generally under hot environment 1000 hours, the resistance deviation of this quasi-resistance namely reaches about 5% on the market, can't satisfy the long-time requirement of using of high-temperature service; Because chip thickness and density are not enough, repeatedly by electric current the time, the easy breakdown inefficacy of chip.
Summary of the invention
In order to solve prior art problems, the embodiment of the invention provides a kind of composition for the NTC thermistor chip and has used the resistance of this chip.Described technical scheme is as follows:
On the one hand, the invention provides a kind of composition for the preparation of the NTC thermistor chip, the component that wherein comprises and content thereof are:
More than each component be nano-powder, purity is chemical pure,
And make the chip slurry by above-mentioned composition by following step:
(1) takes by weighing raw material according to said components and content;
(2) pour ball mill into after described raw material is mixed, add water grinding 30-50 hour;
(3) the described raw material behind the grinding is carried out dewatered drying;
(4) add adhesive in the described raw material after oven dry and stir, form the chip slurry.
Preferably, the component that comprises and content thereof are:
On the other hand, the invention provides a kind of method of making the NTC thermistor with above-mentioned composition, described method comprises:
(1) component and the content according to above-mentioned composition takes by weighing raw material;
(2) pour ball mill into after described raw material is mixed, add water grinding 30-50 hour;
(3) the described raw material behind the grinding is carried out dewatered drying;
(4) add adhesive in the described raw material after oven dry and stir, form the chip slurry;
(5) described chip slurry is pressed into thin slice;
(6) described thin slice is polished, form ganoid embryo sheet;
(7) with described embryo sheet 1290-1310 ℃ of following high temperature sintering 48 hours, form potsherd;
(8) give described potsherd coated on both sides silver slurry, make electrode;
(9) require to cut the described potsherd that has adhered to silver-colored slurry according to resistance, obtain electroded NTC thermistor chip;
(10) give described electroded NTC thermistor chip welding lead, form the NTC thermistor.
Further, described step (10) also comprises afterwards:
Described NTC thermistor is carried out glass packaging, obtain the NTC thermistor of glass packaging.
Adhesive described in the step (4) is dibutyl phthalate and polyvinyl alcohol milky white adhesive, and its operation specifically comprises:
Adding dibutyl phthalate and polyvinyl alcohol milky white adhesive stir in the described raw material after oven dry, form the chip slurry, the weight of wherein said dibutyl phthalate is 4% of the described raw material weight after drying, and the weight of described polyvinyl alcohol milky white adhesive is 1.5% of the described raw material weight after drying.
Described step (5), (6) specifically comprise:
By repeatedly punching press-dry and repeatedly punching press subsequently-bake operation described chip slurry is pressed into the thick thin slice of 0.8-0.85mm;
By sander described thin slice is polished into the thick ganoid embryo sheet of 0.8mm.
The present invention also provides a kind of usefulness NTC thermistor that above-mentioned manufacture method is made.
The B of described NTC thermistor
25/50Value is 3930K ± 2%.
The beneficial effect that the technical scheme that the embodiment of the invention provides is brought is: by adjusting the proportioning for the preparation of each component in the composition of NTC thermistor chip, the NTC thermistor chip that it is made is thicker than the chip of identical B value, thereby can in the resistance manufacture craft, increase the surface grinding operation of chip embryo sheet, guarantee chip embryo sheet smoothness of the surface and consistency, prevent the resistance drift that resistance long-term work generation performance change causes even the problem that lost efficacy, prolong the useful life of resistance, improved its certainty of measurement; The thermal time constant of the NTC thermistor that the embodiment of the invention provides can reach 3.8s, can quick temperature measurement, and experiment 1000 hours under 150 ℃ of high temperature, resistance deviation can better satisfy the instructions for use of high-temperature service less than 1%; Simultaneously, because the chip thickening, electric current is resistance to sparking easily, has improved the anti-rush of current performance of resistance.
Description of drawings
In order to be illustrated more clearly in the technical scheme in the embodiment of the invention, the accompanying drawing of required use is done to introduce simply in will describing embodiment below, apparently, accompanying drawing in describing below only is some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the potsherd that the embodiment of the invention provides;
Fig. 2 is the potsherd that has adhered to silver-colored slurry that the embodiment of the invention provides.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, embodiment of the present invention is described further in detail below in conjunction with accompanying drawing.
One, material therefor and instrument in the embodiment of the invention
Mn
3O
4Nano-powder, Fe
2O
3Nano-powder, SiO
2Nano-powder, NiO nano-powder, silver slurry (comprise silver slurry and silver slurry diluent complete sets of products, product type is SR402H) all buy the CO. from KOJUNDO CHEMICAL LABORATORY, LTD (Japanese high-purity chemical research institute), the purity of each nano-powder all reaches chemical pure; Dibutyl phthalate (B oil) is bought from Korea S OCI company, and model is (C
16H
22O
4)=278.35; Polyvinyl alcohol milky white adhesive model is C-501, buys from Korea S OKONG company; The silica gel model is KR-251, buys from Japan XINYUE.
Ball mill is bought from Korea S DAE WHA TECH company, and the thermistor glass shell is bought from Shenzhen Hua Keyuan Science and Technology Ltd..
The manufacture method of the NTC thermistor that two, adopts in the embodiment of the invention
Step (1): take by weighing raw material by following weight portion proportioning: Mn
3O
4665-670 part, Fe
2O
3110-115 part, SiO
216-20 part, NiO 200-205 part.
Step (2): the described raw material that will weigh up mixes, and pours in the ball mill, adds 2500ml water, grinding 30-50 hour in ball mill.
Step (3): the raw material behind the taking-up grinding, put into baking oven, under 125 ℃, bake 10-12 hour to the raw material dewatered drying.
Step (4): take out the raw material of oven dry, take by weighing 500g in the described raw material after oven dry, add adhesive and stir, form the chip slurry.The adhesive that uses in this step is 20g dibutyl phthalate and 7.5g polyvinyl alcohol milky white adhesive.According to the adhesive bonding force of this method proportioning by force, not volatile, the chemical property of raw material is not had influence, and its material viscosity is moderate, is conducive to evenly mix with raw material.
Step (5): the embryo sheet that described chip slurry is pressed into 0.8mm.
Earlier by technologies such as repeatedly punching press-dry or punching presses-bake described chip slurry is pressed into the thick thin slice of 0.8-0.85mm in the embodiment of the invention, by sander described thin slice is polished into the thick embryo sheet of 0.8mm then.
For example, concrete operations step is:
A, with tablet press machine the chip slurry is pressed into the thick thin slice of 0.9mm;
B, fix with the big clip thin slice that 0.9mm is thick, hang 20min at ambient temperature thin slice is dried;
C, the thin slice that 0.9mm is thick are pressed into the thick thin slice of 0.85mm;
D, the thin slice that 0.85mm is thick are cut into the rectangular of wide about 44mm, and with rectangular the coming on the stainless (steel) wire of being cut into, positive and negative respectively dried in the air 10 minutes at ambient temperature;
E, the rectangular thin slice that 0.85mm is thick are pressed into thick rectangular of 0.83mm;
F, the rectangular thin slice that 0.83mm is thick are cut into the square sheets that the length of side is 44mm, and the square sheets that is cut into is come on the stainless (steel) wire, put into baking oven and bake 10min;
G, the square sheets that 0.83mm is thick are pressed into the thick thin slice of 0.82mm;
F, the thin slice that 0.82mm is thick are placed on the glass plate, under the control of PID (proportional-integral-differential) controller, under 60 ℃, baked 12 hours earlier, be cooled to carry out secondary behind the normal temperature and cure, when secondary cured, PID controller temperature control baked 1 hour under 60 ℃, under 70 ℃, baked 1 hour, under 80 ℃, baked 1 hour, under 90 ℃, baked 1 hour, under 100 ℃, baked 1 hour, under 110 ℃, baked 1 hour, under 125 ℃, baked 6 hours.
Step (6): bake and finish the thick thin slice of back taking-up 0.82mm, be polished into the thick embryo sheet of 0.8mm with the sander two sides.
Step (7): described embryo sheet 1290-1310 ℃ of following high temperature sintering 48 hours, is formed potsherd shown in Figure 1.
Step (8): give described potsherd coated on both sides silver slurry, make electrode (referring to Fig. 2).
In following embodiment of the present invention, these step concrete operations are as follows:
Dilution silver slurry: the silver slurry is 100: 5 with the weight ratio of silver slurry diluent;
Print electrode: after treating that potsherd cools off fully, to the silver slurry after the potsherd printing dilution, printing is carried out at twice, and the potsherd that all will be brushed with the silver slurry after each printing finishes is arranged on the stainless (steel) wire, bakes 10-15 minute until drying under 125 ℃;
Roasting: the fire-resistant box of packing into of the potsherd after printing dried, put into sintering furnace 850 ℃ of following sintering 8 hours, make electrode.
Step (9): require to cut the described potsherd that has adhered to silver-colored slurry according to resistance, obtain electroded NTC thermistor chip.
In following embodiment of the present invention, the potsherd that will have electrode is cut into the fritter of 0.43*0.40mm, and the formation resistance is R
25 ℃=100K Ω ± 2%, B
25/50The electroded NTC thermistor chip of=3930K ± 2%.
Step (10): give described electroded NTC thermistor chip welding lead, form the NTC thermistor.
All adopt the scolding tin welding lead in the concrete operations.
For better protection NTC thermistor chip, improve the useful life of chip, the manufacture method that the embodiment of the invention provides also comprises the steps:
Step (11): described NTC thermistor is carried out glass packaging, obtain the NTC thermistor of glass packaging.
This step is specially:
The NTC thermistor is inserted in the thermistor glass shell, clamps thermistor glass shell and NTC thermistor with frock clamp, in 660 ℃ of bakings down of high temperature, make thermistor glass shell shrink wrapped resistance, realize encapsulation.
Three, the performance test methods of the NTC thermistor chip that provides of the embodiment of the invention comprises rush of current test, high temperature test, stability test, thermal time constant test etc., and every embodiment has chosen three samples in the test, and concrete method of testing is as follows:
(1) rush of current test: the NTC thermistor chip that under 120 ℃ the embodiment of the invention is provided (the benchmark resistance is 3.811K Ω) carries out the direct current energizing test, the direct voltage that the NTC thermistor chip is loaded raises gradually from 5V, in galvanization, detect the resistance output of resistance, choose resistance or B value respectively and change above the current point of original value 3% and the current point of chip puncture, test data is referring to table 1;
(2) high temperature test: under the 5V direct voltage, resistance toasted 1000 hours in the environment of 150 ℃ ± 2 ℃ of high temperature, the variation of test resistance and B value, and test data is referring to table 2;
(3) stability test: under the 5V direct voltage, with the thermal shock machine NTC thermistor chip that the embodiment of the invention provides is carried out impact experiment ,-40 ℃ following 20 minutes, 150 ℃ following 20 minutes, 2 minutes intermediate conversion time, carry out 1000 circulations, test data is referring to table 3;
(4) thermal time constant is measured: the NTC thermistor that the embodiment of the invention provides is put into 50 ℃ of Water Tanks with Temp.-controlled, treat the stable back of resistance its resistance of mensuration, record initial resistance data; Then described NTC thermistor is transferred to rapidly in 25 ℃ of Water Tanks with Temp.-controlled, observed change in resistance, the record change in resistance is the 63.2% o'clock used time of initial resistance, and this time is the thermal time constant of NTC thermistor.
The making of 1 one kinds of NTC thermistors of embodiment
Described NTC thermistor makes according to above-mentioned two described manufacture methods, and wherein: the raw material that takes by weighing in the step (1) is: Mn
3O
4665g, Fe
2O
3110g, SiO
216g, NiO 200g.
The making of 2 one kinds of NTC thermistors of embodiment
Described NTC thermistor makes according to above-mentioned two described manufacture methods, and wherein: the raw material that takes by weighing in the step (1) is: Mn
3O
4670g, Fe
2O
3115g, SiO
220g, NiO 205g.
The making of 3 one kinds of NTC thermistors of embodiment
Described NTC thermistor makes according to above-mentioned two described manufacture methods, and wherein: the raw material that takes by weighing in the step (1) is: Mn
3O
4668g, Fe
2O
3112g, SiO
218g, NiO 202g.
The making of 4 one kinds of NTC thermistors of embodiment
Described NTC thermistor makes according to above-mentioned two described manufacture methods, and wherein: the raw material that takes by weighing in the step (1) is: Mn
3O
41490gg, Fe
2O
3250g, SiO
240g, NiO 450g.
The data parameters of the NTC thermistor performance test that embodiment 1-4 provides is as follows:
The rush of current test data of the NTC thermistor chip that table 1 embodiment of the invention 1-4 provides
The high temperature test data of the NTC thermistor chip that table 2 embodiment of the invention 1-4 provides
The stability test data of the NTC thermistor chip that table 3 embodiment of the invention 1-4 provides
The thermal time constant data of the NTC thermistor chip that table 4 embodiment of the invention 1-4 provides
Referring to table 1, the chip of the NTC thermistor that embodiment of the invention 1-4 provides all can tolerate the above electric current of 16mA, and according to the specification of like product as can be known, the resistance chip of most of like products generally tolerates the electric current of 5mA only, so the NTC thermistor chip that the embodiment of the invention provides has good anti-rush of current;
Referring to table 2, the NTC thermistor chip that the embodiment of the invention provides toasted 1000 hours under 150 ℃ of hot environments, and change in resistance is no more than 0.4%, and resistance is stable, has the good temperature resistance energy;
Referring to table 3, the NTC thermistor chip that the embodiment of the invention is provided carries out cold shock testing, and resistance varying-ratio and B value rate of change are all less than 1% after 1000 shock tests.
Referring to table 4, the thermal time constant of the NTC thermistor that the embodiment of the invention provides all can reach 3.8 seconds, be significantly shorter than existing similar NTC thermistor, thereby the NTC thermistor temperature detecting speed that the embodiment of the invention provides is fast.
Test the rate of finished products of the NTC thermistor that the embodiment of the invention provides as follows:
The NTC thermistor that embodiment of the invention 1-4 is provided is divided into 5 batches respectively, detects resistance and the B value of each batch resistance, and resistance and B value change and be no more than 1% product and be qualified finished product.
The NTC thermistor rate of finished products that the embodiment of the invention is made reaches 95.3%, and at present the rate of finished products of the NTC thermistor produced of other domestic production enterprise mostly about 70%, the present invention has improved the rate of finished products of NTC thermistor greatly, has reduced production cost, has tangible price advantage.
The above only is preferred embodiment of the present invention, and is in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (6)
1. a method of making the NTC thermistor is characterized in that, described method comprises:
(1) take by weighing raw material according to component and content for the preparation of the composition of NTC thermistor chip, the component that described composition comprises and content thereof are:
(2) pour ball mill into after described raw material is mixed, add water grinding 30-50 hour;
(3) the described raw material behind the grinding is carried out dewatered drying;
(4) add adhesive in the described raw material after oven dry and stir, form the chip slurry;
(5) described chip slurry is pressed into thin slice, specifically comprises: by repeatedly punching press-dry and punching press subsequently-bake operation described chip slurry is pressed into the thick thin slice of 0.8-0.85mm;
(6) described thin slice is polished, form ganoid embryo sheet, specifically comprise: by sander described thin slice is polished into the thick ganoid embryo sheet of 0.8mm;
(7) with described embryo sheet 1290-1310 ℃ of following high temperature sintering 48 hours, form potsherd;
(8) give described potsherd coated on both sides silver slurry, make electrode;
(9) require to cut the described potsherd that has adhered to silver-colored slurry according to resistance, obtain electroded NTC thermistor chip;
(10) give described electroded NTC thermistor chip welding lead, form the NTC thermistor.
2. according to claim 1 for the method for making the NTC thermistor, it is characterized in that the component that described composition comprises and content thereof are:
3. the method for making according to claim 1 NTC thermistor is characterized in that described step (10) also comprises afterwards:
Described NTC thermistor is carried out glass packaging, obtain the NTC thermistor of glass packaging.
4. the method for making NTC thermistor according to claim 1 is characterized in that the adhesive described in the step (4) is dibutyl phthalate and polyvinyl alcohol milky white adhesive, and its operation specifically comprises:
Adding dibutyl phthalate and polyvinyl alcohol milky white adhesive stir in the described raw material after oven dry, form the chip slurry, the weight of wherein said dibutyl phthalate is 4% of the described raw material weight after drying, and the weight of described polyvinyl alcohol milky white adhesive is 1.5% of the described raw material weight after drying.
5. with any NTC thermistor that described manufacture method is made among the claim 1-4.
6. NTC thermistor according to claim 5 is characterized in that, the B of described NTC thermistor
25/50Value is 3930K ± 2%.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109133901A (en) * | 2018-10-29 | 2019-01-04 | 惠州嘉科实业有限公司 | Thermistor containing iron series and preparation method thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104370526B (en) * | 2013-08-15 | 2016-07-13 | 中国振华集团云科电子有限公司 | A kind of preparation method with resistance negative temperature coefficient Magnetite |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101922980A (en) * | 2010-07-23 | 2010-12-22 | 深圳市敏杰电子科技有限公司 | NTC (Negative Temperature Coefficient) temperature sensor and molding process thereof |
| CN102270531A (en) * | 2011-04-28 | 2011-12-07 | 中国科学院新疆理化技术研究所 | Preparation method of laminated sheet-type negative temperature coefficient thermistor |
Family Cites Families (1)
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|---|---|---|---|---|
| JPH0797269A (en) * | 1993-09-27 | 1995-04-11 | Mitsubishi Materials Corp | Production of low-temperature sintering ceramic |
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2012
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101922980A (en) * | 2010-07-23 | 2010-12-22 | 深圳市敏杰电子科技有限公司 | NTC (Negative Temperature Coefficient) temperature sensor and molding process thereof |
| CN102270531A (en) * | 2011-04-28 | 2011-12-07 | 中国科学院新疆理化技术研究所 | Preparation method of laminated sheet-type negative temperature coefficient thermistor |
Non-Patent Citations (3)
| Title |
|---|
| "薄膜封装型NTC热敏电阻器的研制";袁国安 等;《电子元件与材料》;20071231;第26卷(第7期);第57-59页 * |
| JP特开平7-97269A 1995.04.11 |
| 袁国安 等."薄膜封装型NTC热敏电阻器的研制".《电子元件与材料》.2007,第26卷(第7期),第57-59页. |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109133901A (en) * | 2018-10-29 | 2019-01-04 | 惠州嘉科实业有限公司 | Thermistor containing iron series and preparation method thereof |
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