Abstract:
This invention relates to a ceramic composition, which is suitable for use in DOC and DPF for removing nitrogen oxide, carbon monoxide and unburned particles from exhaust gas systems of vehicles or for use in a thermistor temperature sensor for an industrial high-temperature environment similar thereto, and to a thermistor device manufactured using the composition. The ceramic composition is prepared by adding a perovskite phase having a perovskite crystalline structure represented by ABO3 with Sn of Group 4B or Sb or Bi of Group 5B, wherein A includes at least one element selected from among Groups 2A and 3A elements except for LA, and B includes at least one element selected from among transition metals of Groups 4A, 5A, 6A, 7A, 8A, 2B and 3B.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a continuation of International Application No. PCT/KR2013/004779 filed May 30, 2013, which claims priority to Korean Application No. 10-2012-0069731 filed on Jun. 28, 2012. The applications are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a ceramic composition, which is suitable for use in a diesel oxidation catalyst (DOC) and a diesel particulate filter (DPF) for removing nitrogen oxide, carbon monoxide and unburned particles from exhaust gas systems of vehicles or for use in a thermistor temperature sensor for an industrial high-temperature environment similar thereto, and to a thermistor device manufactured using the composition. 
       BACKGROUND ART 
       [0003]    The present invention relates to a ceramic composition, which is suitable for use in DOC and DPF for removing nitrogen oxide, carbon monoxide and unburned particles from exhaust gas systems of vehicles or for use in a thermistor temperature sensor for an industrial high-temperature environment similar thereto, and to a thermistor device manufactured using the composition. 
         [0004]    Five to ten kinds of temperature sensors are applied to vehicles. Almost all kinds of sensors used in the temperature sensors include a ceramic thermistor using an oxide semiconductor. The reason why the ceramic thermistor is used is that it is inexpensive and satisfies reliability required of vehicles. Although the temperature range of the ceramic thermistor may vary depending on the application position thereof, when it is applied to an engine room, the temperature range may be set to −40˜150° C., and in the case of HVAC, the temperature range of −40˜80° C. is applied. 
         [0005]    In addition, a vehicle sensor, which is newly receiving attention, requires an increase in fuel efficiency based on international environmental regulations and also the detection of temperature, pressure, oxygen or nitrogen content of exhaust systems by the regulation of harmful components of exhaust gases. 
         [0006]    The sensing range of the temperature sensor for use in an exhaust gas system is typically set to 300˜800° C. In the case of DPF, the temperature range of −40˜900° C. should be set so as to satisfy international OBD II standards. 
         [0007]    Furthermore, as a direct spray manner is applied to a gasoline engine, a gasoline engine needs a filter for filtering exhaust gas discharged upon initial startup in cold weather. In the case of the gasoline engine, the temperature up to 1000° C. should be measured, which is regarded as difficult. Hence, there is a need for a composition having a low B constant relative to a high resistance value in order to satisfy such a temperature range. 
         [0008]    In this regard, conventional techniques include U.S. Pat. No. 6,306,315 (Patent Document 1) and U.S. Pat. No. 7,656,269 (Patent Document 2). In the case of the oxide disclosed in Patent Document 1, the resistance at −40° C. is 110˜100 Ω, and the B constant is 2200˜2480K Furthermore, the resistance at about 900° C. is maintained to the level of 50Ω or less, and thus high-temperature resolution becomes poor, and output voltage is lowered to about 0.1 V, undesirably decreasing consumer utilization. 
         [0009]    Patent Document 2 shows similar trends to Patent Document 1. 
         [0010]    Moreover, in the case where the oxide is allowed to stand for a long period of time at high temperature, a change over time at high temperature is regarded as important. There is thus a continuous need for the development of an oxide having improved properties. 
       SUMMARY 
       [0011]    Accordingly, an object of the present invention is to provide a ceramic composition for a thermistor temperature sensor and a thermistor device manufactured using the composition, wherein a conventional oxide may be added with another kind of oxide, thus exhibiting appropriate resistance and a low B constant. 
         [0012]    Another object of the present invention is to provide a ceramic composition for a thermistor temperature sensor and a thermistor device manufactured using the composition, wherein the measurement of a temperature in the wide range of −40˜1000° C. is possible. 
         [0013]    In order to accomplish the above objects, the present invention provides a ceramic composition for a thermistor temperature sensor, prepared by adding a perovskite phase having a perovskite crystalline structure represented by ABO3 with Sn of Group 4B or Sb or Bi of Group 5B, wherein A comprises at least one element selected from among Groups 2A and 3A elements except for LA, and B comprises at least one element selected from among transition metals of Groups 4A, 5A, 6A, 7A, 8A, 2B and 3B. 
         [0014]    According to a preferred embodiment of the present invention, the mixing ratio of A and B in the perovskite crystalline structure represented by ABO3 is 1:1, and when the element of A is set to M1; the element of B is set to M2; and Sn of Group 4B or Sb or Bi of Group 5B is set to M3, M1, M2 and M3 satisfy one or more selected from among the following relations: 
         [0000]      0 ≦M 1≦1
 
         [0000]      0 ≦M 2 +M 3≦1
 
         [0000]      0 ≦M 3≦0.6.
 
         [0015]    According to a more preferred embodiment of the present invention, M1 may comprise one or more selected from the group consisting of Y 2 O 3 , CaCO 3 , SrO 2  and MgO. 
         [0016]    According to a more preferred embodiment of the present invention, M2 may comprise one or more selected from the group consisting of MnO 2 , Cr 2 O 3  and NiO. 
         [0017]    According to a more preferred embodiment of the present invention, M3 may comprise one or more selected from the group consisting of CuO, SnO, Sb 2 O 3 , Bi 2 O 3 , Al 2 O 3  and Fe 2 O 3 . 
         [0018]    According to a much more preferred embodiment of the present invention, the ceramic composition may have a temperature gradient constant of 1800˜2600K in the temperature range of −40˜1000° C. 
         [0019]    In addition, the present invention provides a thermistor device, manufactured using the ceramic composition as above. 
         [0020]    In addition, the present invention provides a temperature sensor, manufactured using the thermistor device as above. 
         [0021]    According to the present invention, a ceramic composition for a thermistor temperature to sensor and a thermistor device manufactured using the composition can exhibit appropriate resistance and a low B constant by adding Sn as a Group 4B element or Sb or Bi as a Group 5B element. 
         [0022]    Also, the present invention can very effectively provide a thermistor temperature sensor that is able to measure the temperature in the wide range of −40˜1000° C. 
     
    
     DETAILED DESCRIPTION 
       [0023]    Hereinafter, a detailed description will be given of preferred embodiments of the present invention and properties of individual components, which is intended to specifically describe the invention to the extent that the invention may be easily performed by those skilled in the art, but is not construed to limit the spirit and scope of the present invention. 
         [0024]    According to the present invention, a ceramic composition for a thermistor temperature sensor is prepared by adding a perovskite phase having a perovskite crystalline structure represented by ABO3 with Sn or Si as a Group 4B element or Sb or Bi as a Group 5B element, wherein A includes at least one element selected from among Groups 2A and 3A elements except for LA, and B includes at least one element selected from among transition metals of Groups 4A, 5A, 6A, 7A, 8A, 2B and 3B. 
         [0025]    Also, the mixing ratio of A and B in the perovskite crystalline structure represented by ABO3 is 1:1, and when the element of A is set to M1; the element of B is set to M2; and Sn as a Group 4B element or Sb or Bi as a Group 5B element is set to M3, M1, M2 and M3 satisfy one or more selected from among the following relations: 
         [0000]      0 ≦M 1≦1
 
         [0000]      0 ≦M 2 +M 3≦1
 
         [0000]      0 ≦M 3≦0.6.
 
         [0026]    Conventionally, an oxide is a sintered material having a perovskite structure of M1M2O3, and is configured such that the oxide having a large atomic radius among elements belonging to M1 and M2 is positioned at M1 and the oxide having a comparatively small atomic radius is positioned at M2, so as to facilitate substitution upon synthesis. 
         [0027]    In the present invention, as the composition of M1 and M2 is added with M3, the B constant of a thermistor is lowered and also changes in resistance to external heat are reduced to achieve stabilization of the phase. Furthermore, M3 is added to the composition to adjust the number of holes, control a particle size and space between the particles and hinder migration of electrons at different temperatures, and thereby the resulting composition has a lowered B constant and is decreased in deviation depending on the lot of products. 
         [0028]    To this end, in a method of manufacturing an NTC thermistor, when ABO3 is configured to include M1 (Y 2 O 3 , CaCO 3 , SrO 2 , MgO) including Groups 2A˜3A, M2 (MnO 2 , Cr 2 O 3 , NiO) including transition metals, and M3 (CuO, SnO, Sb 2 O 3 , Bi 2 O 3 , Al 2 O 3 , Fe 2 O 3 ) including Group 4B or 5B, the composition of A and B at 1:1 is provided, wherein A is composed mainly of M1 and B is composed mainly of M2+M3. 
         [0029]    The powder components having no M3 were primarily mixed at the mixing ratios shown in Table 1 using wet mixing, and dried at 120° C. for 8 hr, thus obtaining synthetic powder. Subsequently, the dried powder was calcined at 900˜1100° C. for 2˜4 hr, pulverized so as to obtain an average particle size of 0.2˜0.6 μm, after which 90 wt % of the pulverized product was added with 10 wt % of a polyvinyl acetate (PVA) binder, followed by performing spray drying, thus preparing spherical powder, which was then sieved using a sieve of 500 mesh, yielding final powder. 
         [0030]    The final powder thus obtained was placed in a special molding machine to obtain a molded body coupled with platinum wires, which was then sintered at 1400˜1550° C. for 2∞4 hr, thereby manufacturing a thermistor device, the resistance values of which were measured at −40° C., 600° C. and 900° C., and B constants were determined by the equation. 
         [0031]    The initial resistance values of the thermistor device were measured at −40° C., 600° C. and 900° C. Thereafter, the product was aged at 900° C. for 100 hr, after which resistance values to thereof were measured at −40° C., 600° C., and 900° C. as in the initial conditions, and changes in resistance after aging relative to the initial values were evaluated. 
         [0032]    The B constant was calculated by the following equation, and the resistance deviation was calculated, thus determining a resistance change. The results are given in Table 1 below. 
       ti  B ( R 1 /R 2)=In[ R 1 /R 2]/[1 /T 1−1 /T 2] 
       [0033]    As shown in Table 1, as the component ratio of M1 and M2 was adjusted, compositions having desired B constants and resistance values at −40° C. were selected, and the amount of M3 (Group 1B, 4B, 5B) oxide was changed, so that B constants and resistivity changes were evaluated. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                   
                   
                   
                   
                 B  
                 Resistance 
               
             
          
           
               
                 Sample 
                 M1 
                 M2 
                   
                 M1 
                 M2 
                 R-40 
                 R100 
                 R600 
                 R900 
                 (−40/ 
                 Change 
               
               
                 No. 
                 Element 
                 Element 
                 Total 
                 Element 
                 Element 
                 (kΩ) 
                 (kΩ) 
                 (kΩ) 
                 (kΩ) 
                 900) 
                 (%) 
               
               
                   
               
             
          
           
               
                 1 
                 45 
                 5 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 54.93 
                 0.897 
                 0.0147 
                 0.0077  
                 2582 
                 15 
               
               
                 2 
                 45 
                 5 
                 30 
                 20 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 30.44 
                 0.649 
                 0.018 
                 0.0062  
                 2473 
                 13 
               
               
                 3 
                 45 
                 5 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 12.62 
                 0.245 
                 0.009 
                 0.004 
                 2344 
                 18 
               
               
                 4 
                 45 
                 5 
                 10 
                 40 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 1780 
                 74.12 
                 0.898 
                 0.295 
                 2533 
                 20 
               
               
                 5 
                 40 
                 10 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 1.269 
                 0.118 
                 0.009 
                 0.004 
                 1676 
                 14 
               
               
                 6 
                 40 
                 10 
                 30 
                 20 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 10.3 
                 0.680 
                 0.066 
                 0.019 
                 1832 
                 13 
               
               
                 7 
                 40 
                 10 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 15.23 
                 0.367 
                 0.016 
                 0.006 
                 2281 
                 21 
               
               
                 8 
                 40 
                 10 
                 10 
                 40 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 126 
                 10.01 
                 0.049 
                 0.01 
                 2747 
                 18 
               
               
                 9 
                 45 
                 5 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 1264 
                 1.318 
                 0.015 
                 0.004  
                 3685 
                 15 
               
               
                 10 
                 45 
                 5 
                 30 
                 20 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 395.2 
                 0.649 
                 0.018 
                 0.007  
                 3184 
                 13 
               
               
                 11 
                 45 
                 5 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 22.61 
                 0.380 
                 0.008 
                 0.003  
                 2598 
                 18 
               
               
                 12 
                 45 
                 5 
                 10 
                 40 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 12963 
                 256.14 
                 12.64 
                 3.695 
                 2375 
                 20 
               
               
                 13 
                 40 
                 10 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 9912641 
                 1093 
                 1.095 
                 0.268  
                 5071 
                 14 
               
               
                 14 
                 40 
                 10 
                 30 
                 20 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 557.1 
                 1.642 
                 0.032 
                 0.007  
                 3284 
                 13 
               
               
                 15 
                 40 
                 10 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 31.92 
                 0.192 
                 0.011 
                 0.004  
                 2614 
                 21 
               
               
                 16 
                 40 
                 10 
                 10 
                 40 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 93162 
                 128.1 
                 0.169 
                 0.061  
                 4143 
                 18 
               
               
                 17 
                 45 
                 5 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Al 
                 11229 
                 22.35 
                 0.681 
                 0.056  
                 3552 
                 15 
               
               
                 18 
                 45 
                 5 
                 30 
                 20 
                 100 
                 Y, Ca 
                 Mn, Al 
                 36125 
                 1.009 
                 0.029 
                 0.008  
                 4459 
                 4 
               
               
                 19 
                 45 
                 5 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Al 
                 631561 
                 92.610 
                 0.164 
                 0.061  
                 4700 
                 8 
               
               
                 20 
                 45 
                 5 
                 10 
                 40 
                 100 
                 Y, Ca 
                 Mn, Al 
                 5612462 
                 103.9 
                 0.267 
                 0.091  
                 5219 
                 10 
               
               
                 21 
                 40 
                 10 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Al 
                 613.3 
                 2.641 
                 0.026 
                 0.006  
                 3356 
                 7 
               
               
                 22 
                 40 
                 10 
                 30 
                 20 
                 100 
                 Y, Ca 
                 Mn, Al 
                 22681 
                 64.160 
                 0.166 
                 0.008  
                 4323 
                 6 
               
               
                 23 
                 40 
                 10 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Al 
                 634516 
                 326.4 
                 4.621 
                 0.913  
                 3914 
                 10 
               
               
                 24 
                 40 
                 10 
                 10 
                 40 
                 100 
                 Y, Ca 
                 Mn, Al 
                 5531672 
                 1283 
                 4.612 
                 0.643  
                 4646 
                 9 
               
               
                   
               
             
          
         
       
     
         [0034]    As is apparent from Table 1, compositions having B constants and resistance values at −40° C. approximate to desired values and low resistance changes upon manufacturing thermistor devices without synthesis of additives using the same ceramic preparation method as above were adopted in order to select base compositions. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 Sample 
                 M1 
                 M2 
                 M3 
                   
                 M1 
                 M2 
                 M3 
                 R100 
                 R600 
                 B(100/  
                 Resistance 
               
               
                 No. 
                 Element 
                 Element 
                 Element 
                 Total 
                 Element 
                 Element 
                 Element 
                 (kΩ) 
                 (kΩ) 
                 600) 
                 Change (%) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 2-1  
                 50 
                 50 
                 0 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 — 
                 0.649 
                 0.018 
                 2336 
                 13 
               
               
                 2-2  
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.612 
                 0.017 
                 2335 
                 19 
               
               
                 2-3  
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.513 
                 0.016 
                 2260 
                 23 
               
               
                 2-4  
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.235 
                 0.01 
                 2057 
                 25 
               
               
                 2-5  
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.082 
                 0.005 
                 1823 
                 31 
               
               
                 2-6  
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.136 
                 0.006 
                 2034 
                 48 
               
               
                 2-7  
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.053 
                 0.004 
                 1684 
                 35 
               
               
                 2-8  
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.623 
                 0.018 
                 2309 
                 7 
               
               
                 2-9  
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.511 
                 0.017 
                 2218 
                 3 
               
               
                 2-10 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.366 
                 0.013 
                 2175 
                 5 
               
               
                 2-11 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.568 
                 0.018 
                 2249 
                 9 
               
               
                 2-12 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.891 
                 0.021 
                 2442 
                 16 
               
               
                 2-13 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 1.634 
                 0.041 
                 2401 
                 22 
               
               
                 2-14 
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 1.721 
                 0.046 
                 2360 
                 5 
               
               
                 2-15 
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 0.822 
                 0.021 
                 2390 
                 2 
               
               
                 2-16 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 1.082 
                 0.029 
                 2358 
                 4 
               
               
                 2-17 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 3.264 
                 0.085 
                 2377 
                 6 
               
               
                 2-18 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 5.326 
                 0.138 
                 2380 
                 10 
               
               
                 2-19 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 12.620  
                 0.334 
                 2367 
                 15 
               
               
                 2-20 
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 0.823 
                 0.021 
                 2390 
                 6 
               
               
                 2-21 
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 0.921 
                 0.025 
                 2350 
                 3 
               
               
                 2-22 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 1.356 
                 0.036 
                 2365 
                 3 
               
               
                 2-23 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 3.621 
                 0.0956  
                 2368 
                 7 
               
               
                 2-24 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 9.162 
                 0.246 
                 2357 
                 9 
               
               
                 2-25 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 16.023  
                 0.426 
                 2364 
                 16 
               
               
                   
               
             
          
         
       
     
         [0035]    In the compositions of Table 1, Y and Ca were positioned at the A site. At the B site, Mn and Cr, Fe or Al were positioned at different ratios, provided that the total sum thereof was maintained at 50 wt %, and B constants and resistance changes after aging at respective temperatures were measured. 
         [0036]    The composition of Sample No. 2 in Table 1 was added with Cu of Group 1B, Sn of Group 4B, and Bi and Sb of Group 5B at predetermined ratios, and thus the resulting samples were measured in terms of B constants, resistance values and resistance changes. 
         [0037]    To increase stability of resistance changes, Cu, Sn, Sb or Bi was added in amounts of 1 wt %, 3 wt %, 5 wt %, 10 wt %, 30 wt % and 50 wt %. The addition of impurities and additives in the ABO3 structure such as perovskite was effective at decreasing the rate of recombination of electrons and holes and increasing thermal stability, and had no great influence on the B constant relative to the resistance value but resulted in reduced changes in the samples. 
         [0038]    When adding +3 ions such as Sb or Bi, part of the A site is substituted and thus electrical conduction is performed by electronic interaction and exchange of Y ions. Upon excessive addition, an excess of such an additive is mainly positioned at the intergranular face and thus hinders the migration of electrons at room temperature or a comparatively low temperature of 300° C. or less, and thereby the resistance value is increased but the B constant is maintained almost the same. 
         [0039]    Sample No. 2-19 or 2-25 of Table 2 represents such an electrical principle. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 3 
               
               
                   
               
               
                 Sample 
                 M1 
                 M2 
                 M3 
                   
                 M1 
                 M2 
                 M3 
                 R100 
                 R600 
                 B(100/ 
                 Resistance 
               
               
                 No. 
                 Element  
                 Element 
                 Element 
                 Total 
                 Element 
                 Element  
                 Element 
                 (kΩ) 
                 (kΩ) 
                 600) 
                 Change (%) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 6-1  
                 50 
                 50 
                 0 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 — 
                 0.680 
                 0.032 
                 1992 
                 13 
               
               
                 6-2  
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.521 
                 0.024 
                 2006 
                 13 
               
               
                 6-3  
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.361 
                 0.021 
                 1853 
                 19 
               
               
                 6-4  
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.213 
                 0.015 
                 1729 
                 26 
               
               
                 6-5  
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.081 
                 0.007 
                 1596 
                 28 
               
               
                 6-6  
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.136 
                 0.009 
                 1769 
                 32 
               
               
                 6-7  
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Cu 
                 0.312 
                 0.016 
                 1936 
                 48 
               
               
                 6-8  
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.615 
                 0.029 
                 1990 
                 9 
               
               
                 6-9  
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.601 
                 0.027 
                 2022 
                 5 
               
               
                 6-10 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.511 
                 0.026 
                 1941 
                 6 
               
               
                 6-11 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.623 
                 0.029 
                 1999 
                 9 
               
               
                 6-12 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 0.936 
                 0.036 
                 2123 
                 15 
               
               
                 6-13 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sn 
                 11.623 
                 0.062 
                 3410 
                 22 
               
               
                 6-14 
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 0.721 
                 0.028 
                 2117 
                 4 
               
               
                 6-15 
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 0.925 
                 0.034 
                 2153 
                 3 
               
               
                 6-16 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 1.521 
                 0.054 
                 2175 
                 4 
               
               
                 6-17 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 3.516 
                 0.122 
                 2190 
                 8 
               
               
                 6-18 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 8.125 
                 0.295 
                 2161 
                 11 
               
               
                 6-19 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Sb 
                 16.250 
                 0.562 
                 2192 
                 13 
               
               
                 6-20 
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 0.866 
                 0.031 
                 2170 
                 5 
               
               
                 6-21 
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 1.032 
                 0.039 
                 2135 
                 2 
               
               
                 6-22 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 1.886 
                 0.071 
                 2137 
                 6 
               
               
                 6-23 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 4.416 
                 0.168 
                 2130 
                 11 
               
               
                 6-24 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 8.125 
                 0.312 
                 2124 
                 13 
               
               
                 6-25 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Cr 
                 Bi 
                 16.130 
                 0.632 
                 2111 
                 16 
               
               
                   
               
             
          
         
       
     
         [0040]    Table 3 shows the resistance values, B constants and resistance changes of samples obtained by adding Cu, Sn, Sb and Bi to the composition of Sample No. 6 having a comparatively low B constant relative to a resistance value at −40° C. and good resistance change. 
         [0041]    When Cu or Sn is added in an amount up to 30 wt %, the resistance value and B constant are decreased, and when it is added in an amount of 50 wt %, the resistance value is increased. 
         [0042]    However, in the case of Sb or Bi, there is almost no increase in the B constant relative to an increase in the resistance value. In most thermistors, as the resistance value is increased, the B constant is also increased. But, in the case of Sb or Bi, it attracts free electrons excited by heat due to substitution with the element of the B site or may hinder the flow of electrons due to intergranular effects, and thus an increase in the B constant appears to be suppressed. 
         [0043]    Also, when Sb or Bi is allowed to stand at high temperature in some cases, resistance changes are also decreased. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 4 
               
               
                   
               
               
                 Sample 
                 M1 
                 M2 
                 M3 
                   
                 M1 
                 M2 
                 M3 
                 R100 
                 R600 
                 B(100/  
                 Resistance 
               
               
                 No. 
                 Element 
                 Element 
                 Element 
                 Total 
                 Element 
                 Element  
                 Element 
                 (kΩ) 
                 (kΩ) 
                 600) 
                 Change (%) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 10-1  
                 50 
                 50 
                 0 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 — 
                 0.649 
                 0.018 
                 2336 
                 13 
               
               
                 10-2  
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Cu 
                 0.556 
                 0.0143 
                 2385 
                 19 
               
               
                 10-3  
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Cu 
                 0.361 
                 0.0151 
                 2068 
                 23 
               
               
                 10-4  
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Cu 
                 0.267 
                 0.012 
                 2022 
                 25 
               
               
                 10-5  
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Cu 
                 0.133 
                 0.008 
                 1832 
                 32 
               
               
                 10-6  
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Cu 
                 0.061 
                 0.007 
                 1411 
                 48 
               
               
                 10-7  
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Cu 
                 0.694 
                 0.011 
                 2701 
                 51 
               
               
                 10-8  
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sn 
                 1.116 
                 0.014 
                 2853 
                 13 
               
               
                 10-9  
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sn 
                 0.981 
                 0.013 
                 2817 
                 8 
               
               
                 10-10 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sn 
                 1.216 
                 0.015 
                 2864 
                 6 
               
               
                 10-11 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sn 
                 2.163 
                 0.018 
                 3121 
                 15 
               
               
                 10-12 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sn 
                 4.362 
                 0.023 
                 3418 
                 16 
               
               
                 10-13 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sn 
                 8.216 
                 0.031 
                 3636 
                 15 
               
               
                 10-14 
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sb 
                 1.119 
                 0.093 
                 1621 
                 11 
               
               
                 10-15 
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sb 
                 1.468 
                 0.103 
                 1731 
                 3 
               
               
                 10-16 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sb 
                 1.883 
                 0.117 
                 1811 
                 6 
               
               
                 10-17 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sb 
                 3.516 
                 0.244 
                 1738 
                 13 
               
               
                 10-18 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sb 
                 5.136 
                 0.311 
                 1827 
                 15 
               
               
                 10-19 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Sb 
                 9.336 
                 0.615 
                 1772 
                 16 
               
               
                 10-20 
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Bi 
                 1.468 
                 0.086 
                 1849 
                 5 
               
               
                 10-21 
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Bi 
                 1.922 
                 0.094 
                 1967 
                 3 
               
               
                 10-22 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Bi 
                 2.335 
                 0.133 
                 1867 
                 9 
               
               
                 10-23 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Bi 
                 4.446 
                 0.211 
                 1986 
                 17 
               
               
                 10-24 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Bi 
                 7.361 
                 0.308 
                 2068 
                 15 
               
               
                 10-25 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Fe 
                 Bi 
                 10.632 
                 0.416 
                 2112 
                 16 
               
               
                   
               
             
          
         
       
     
         [0044]    Table 4 shows the resistance values, B constants and resistance changes of samples obtained by adding Cu, Sb and Bi oxides in different amounts to the composition of Sample No. 10 having Fe instead of Cr at the M2 position. 
         [0045]    When using the other elements except for Sn, the overall resistance value is low and the B constant is also low, and a high-temperature resistance change becomes stable except for Cu. In particular, Bi exhibits very good resistance stability when being used in an amount of 5% or less. 
         [0046]    Furthermore, in Sample No. 10-19, when the M2 position is completely occupied with Sb, a high resistance value at 600° C. is maintained relative to a high resistance value at 100° C., to and also a low B constant is obtained, but the resistance change is as high as 16%. 
         [0000]    
       
         
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 5 
               
               
                   
               
               
                 Sample 
                 M1 
                 M2 
                 M3 
                   
                 M1 
                 M2 
                 M3 
                 R100 
                 R600 
                 B(100/ 
                 Resistance 
               
               
                 No. 
                 Element 
                 Element 
                 Element 
                 Total 
                 Element 
                 Element 
                 Element 
                 (kΩ) 
                 (kΩ) 
                 600) 
                 Change (%) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 18-1  
                 50 
                 50 
                 0 
                 100 
                 Y, Ca 
                 Mn, Al 
                 — 
                 1.009 
                 0.029 
                 2313 
                 4 
               
               
                 18-2  
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Cu 
                 0.954 
                 0.028 
                 2299 
                 8 
               
               
                 18-3  
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Cu 
                 0.722 
                 0.026 
                 2166 
                 12 
               
               
                 18-4  
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Cu 
                 0.411 
                 0.0201 
                 1967 
                 13 
               
               
                 18-5  
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Cu 
                 0.216 
                 0.016 
                 1696 
                 15 
               
               
                 18-6  
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Cu 
                 0.135 
                 0.014 
                 1477 
                 18 
               
               
                 18-7  
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Cu 
                 0.065 
                 0.008 
                 1363 
                 16 
               
               
                 18-8  
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sn 
                 0.991 
                 0.029 
                 2301 
                 4 
               
               
                 18-9  
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sn 
                 0.846 
                 0.028 
                 2221 
                 3 
               
               
                 18-10 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sn 
                 0.664 
                 0.026 
                 2111 
                 3 
               
               
                 18-11 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sn 
                 0.411 
                 0.021 
                 1938 
                 3 
               
               
                 18-12 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sn 
                 0.316 
                 0.023 
                 1707 
                 3 
               
               
                 18-13 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sn 
                 0.169 
                 0.016 
                 1536 
                 3 
               
               
                 18-14 
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sb 
                 1.113 
                 0.029 
                 2377 
                 2 
               
               
                 18-15 
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sb 
                 1.521 
                 0.039 
                 2387 
                 2 
               
               
                 18-16 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sb 
                 2.684 
                 0.066 
                 2415 
                 2 
               
               
                 18-17 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sb 
                 4.221 
                 0.091 
                 2500 
                 2 
               
               
                 18-18 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sb 
                 6.216 
                 0.127 
                 2535 
                 2 
               
               
                 18-19 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Sb 
                 9.163 
                 0.226 
                 2413 
                 2 
               
               
                 18-20 
                 50 
                 49 
                 1 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Bi 
                 1.335 
                 0.041 
                 2270 
                 2 
               
               
                 18-21 
                 50 
                 47 
                 3 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Bi 
                 1.881 
                 0.094 
                 1952 
                 2 
               
               
                 18-22 
                 50 
                 45 
                 5 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Bi 
                 3.551 
                 0.164 
                 2004 
                 1 
               
               
                 18-23 
                 50 
                 40 
                 10 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Bi 
                 5.556 
                 0.213 
                 2125 
                 2 
               
               
                 18-24 
                 50 
                 20 
                 30 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Bi 
                 7.168 
                 0.224 
                 2258 
                 2 
               
               
                 18-25 
                 50 
                 0 
                 50 
                 100 
                 Y, Ca 
                 Mn, Al 
                 Bi 
                 10.361 
                 0.316 
                 2274 
                 2 
               
               
                   
               
             
          
         
       
     
         [0047]    Table 5 shows the resistance values, B constants and high-temperature resistance changes of samples obtained by adding Cu, Sn, Sb and Bi oxides in different amounts to the composition of Sample No. 18 having Al instead of Cr at the M2 position. 
         [0048]    The addition of Al is intended to increase the overall resistance value but the use of Cu, Sn, Sb or Bi oxide is intended to decrease the B constant. 
         [0049]    In Sample Nos. 18-21˜23, high resistance values and low B constants are maintained, whereas high-temperature resistance changes are considerably stable. This is considered to be because high resistivity and a low B constant are maintained due to interaction of Al oxide and Bi. 
         [0050]    As results of measurement of resistance values, B constants and high-temperature resistance changes of samples obtained by adding the base composition with Cu, Sn, Sb and Bi as shown above, when Sn of Group 4B or Sb or Bi of Group 5B is added, the resistance value is increased and the B constant is decreased, and the high-temperature resistance change becomes stable. 
         [0051]    Also, in the case where the mixing ratio of A and B in ABO3 is 1:1, when M1 elements are provided at the A position; M2+M3 elements are provided at the B position; and the following relations are satisfied: 
         [0000]      0 ≦M 1≦1
 
         [0000]      0 ≦M 2 +M 3≦1
 
         [0000]      0 ≦M 3≦0.6,
 
         [0052]    the resistance value is increased and the B constant is comparatively suppressed, and the change is decreased.