Display substrate and display device

Abstract

This disclosure provides a display substrate and a display device, belonging to the field of display technology. The display substrate of this disclosure includes a first color light-emitting device, a second color light-emitting device, and a third color light-emitting device disposed on a substrate. At a first operating temperature, the product of the difference in the current efficiency ratio between the first and second color light-emitting devices and the difference between the first operating temperature and a reference temperature ranges from 0 to 8.2; the product of the difference in the current efficiency ratio between the first and third color light-emitting devices and the difference between the first operating temperature and the reference temperature ranges from 0 to 11. At a second operating temperature, the product of the difference in the current efficiency ratio between the first and second color light-emitting devices and the difference between the first operating temperature and the reference temperature ranges from 0 to 15.4; the product of the difference in the current efficiency ratio between the first and third color light-emitting devices and the difference between the first operating temperature and the reference temperature ranges from 0 to 21.6.

Description

Technical Field

[0001] This disclosure belongs to the field of display technology, specifically relating to a display substrate and a display device. Background Technology

[0002] In current display devices, red, green, and blue light-emitting devices are typically arranged in a configuration. White light and full-color displays are achieved by mixing these three colors of light. During display, the temperature of the light-emitting devices affects the display effect of each color. Taking the blue light-emitting device as an example, as the temperature increases, its current efficiency changes, affecting its light output and causing color shift in the entire display device when emitting light. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art, and to provide a display basic and a display device.

[0004] In a first aspect, embodiments of this disclosure provide a display substrate, comprising: a substrate, and a first-color light-emitting device, a second-color light-emitting device, and a third-color light-emitting device disposed on the substrate; wherein...

[0005] The light-emitting layer materials of the first color light-emitting device, the second color light-emitting device, and the third color light-emitting device satisfy the following conditions:

[0006] When the first color light-emitting device, the second color light-emitting device, and the third color light-emitting device emit light, the current efficiency ratio of the first color light-emitting device increases or decreases monotonically with increasing operating temperature; the current efficiency ratios of the second color light-emitting device and the third color light-emitting device decrease monotonically with increasing operating temperature.

[0007] When the first color light-emitting device and the second color light-emitting device are operating at the first operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device and the second color light-emitting device and the difference between the first operating temperature and the reference temperature ranges from 0 to 8.2.

[0008] When the first color light-emitting device and the second color light-emitting device are operating at the second operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device and the second color light-emitting device and the difference between the first operating temperature and the reference temperature ranges from 0 to 15.4.

[0009] When the first color light-emitting device and the third color light-emitting device are operating at the first operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device and the third color light-emitting device and the difference between the first operating temperature and the reference temperature is in the range of 0-11.

[0010] When the first color light-emitting device and the third color light-emitting device are operating at the second operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device and the third color light-emitting device and the difference between the first operating temperature and the reference temperature ranges from 0 to 21.6; where,

[0011] The first operating temperature is greater than the reference temperature, and the difference between the two is 20 degrees Celsius; the second operating temperature is less than the reference temperature, and the difference between the two is 35 degrees Celsius.

[0012] The reference temperature is 25 degrees Celsius, the first operating temperature is 45 degrees Celsius, and the second operating temperature is -10 degrees Celsius.

[0013] The first color light-emitting device includes a first color light-emitting layer sandwiched between a first electrode and a second electrode.

[0014] The material of the first color emitting layer includes a hole-type host material, an electron-type host material, and a doped material;

[0015] The hole-type host material of the first color emitting layer includes a silicon-containing compound material; the electron-type host material of the first color emitting layer includes a triazine-containing compound.

[0016] The doping material of the first color emitting layer includes: a phosphorescent material containing platinum, or a superfluorescent material with an energy difference of less than 0.3 eV between the lowest singlet state and the lowest triplet state.

[0017] Wherein, when the doping material of the first color emitting layer is a platinum-containing phosphorescent material, the general chemical formula of the doping material is:

[0018]

[0019] X1 is carbon, and the bond between X1 and M is a covalent bond; X2 is carbon, and the bond between X2 and M is a covalent bond; X3 is carbon or nitrogen, and the bond between X3 and M is a covalent bond; X4 is nitrogen, and the bond between X4 and M is a covalent bond.

[0020] CY2, CY3, and CY4 are all independently C3-C 60 Carbocyclic or C1-C 60 Heterocyclic group; L1, L2, and L3 are each independently a single bond or a bridging group;

[0021] R1, R2, R3, R4 and R 11 In this group, at least one is hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C2-C 60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C 60 Aryloxy group, unsubstituted or substituted C6-C 60 Any functional group in the arylthio group; among which,

[0022] a1, a2, and a3 are all independent and can be 1, 2, or 3;

[0023] b1 is either 1 or 2, and b2, b3 and b4 are all independent integers from 1 to 10.

[0024] In the chemical formula of the doped material of the first color emitting layer, R1, R2, R3, R4 and R 11 Each of these groups is independently hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C2-C 60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C 60 Aryloxy group, unsubstituted or substituted C 6- C 60 Any functional group in the arylthio group.

[0025] In the chemical formula of the doped material of the first color emitting layer, R1, R2, R3, R4 and R 11 It may also include *-Si(R5)(R6)(R7), *-N(R5)(R6), *-B(R5)(R6), *-C(=O)(R5), *-S(=O)2(R5), or *-P(=O)(R5)(R6); where,

[0026] R5, R6, and R7 are all independently hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C 2-C60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C 60 Aryloxy group, unsubstituted or substituted C6-C 60 Any functional group in the arylthio group.

[0027] In the first color emitting layer, at least two of the doping materials R1, R2, R3, R4, R5, and R6 are combined to form unsubstituted or substituted C3-C. 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group.

[0028] In the chemical formula of the doped material of the first color emitting layer, when L1, L2, and L3 are bridging groups, L1 to L3 are each independently *-O-*', *-S-*', *-Se-*', *-S(=O)2-*', *-C(R5)(R6)-*', *-C(R5)=*', *=C(R5)-*', *-C(R5)=C(R6)-*', *-C(=O)-*', *-C(=S)-*', *-C≡C-*', *-B(R5)-*', *-N(R5)-*', *-P(R5)-*', *-Si(R5)(R6)-*', *-P(=O)(R5)-*', or *-Ge(R5)(R6)-*'.

[0029] Wherein, when the doping material of the first color emitting layer is a platinum-containing phosphorescent material, its general chemical formula is:

[0030]

[0031] Wherein, in the first color light-emitting device, when the doping material in the first color light-emitting layer is a superfluorescent material, its chemical formula is:

[0032]

[0033] Wherein, when the doping material of the first color emitting layer is a platinum-containing phosphorescent material, the general chemical formula of the hole-type host material is:

[0034]

[0035] The general chemical formula of the electronic host material is:

[0036]

[0037] When the doping material of the first color emitting layer is a superfluorescent material, the general chemical formula of the hole-type host material is:

[0038]

[0039] The general chemical formula of the electronic host material is:

[0040]

[0041] Secondly, embodiments of this disclosure provide a display device comprising any of the display substrates described above. Attached Figure Description

[0042] Figure 1 The curves show the changes in the current efficiency ratios of the first-color, second-color, and third-color light-emitting devices as the operating temperature increases.

[0043] Figure 2 The curve shows the change in the ratio of the current efficiency of the first-color light-emitting device to that of the second-color light-emitting device as the operating temperature increases.

[0044] Figure 3 The curves show the change in the ratio of current efficiency of the first-color light-emitting device and the third-color light-emitting device as the operating temperature increases.

[0045] Figure 4 This is a schematic diagram of a display substrate provided in an embodiment of the present disclosure.

[0046] Figures 5a-5d The curve showing the change of current efficiency ratio as operating temperature increases, provided in the embodiments of this disclosure.

[0047] Figure 6 The curves show the changes in the current efficiency ratio of the first, second, and third color light-emitting devices in Example 1 as the operating temperature increases.

[0048] Figure 7 The curves show the changes in the current efficiency ratio of the first, second, and third color light-emitting devices in Example 2 as the operating temperature increases.

[0049] Figure 8 This is a schematic diagram of the stacked structure of the light-emitting device provided in the embodiments of this disclosure. Detailed Implementation

[0050] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “including,” “comprising,” or “containing,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0052] Display devices include liquid crystal displays (LCDs), organic light-emitting diode displays (OLEDs), and flexible displays (AMOLEDs). Taking AMOLED as an example, currently mass-produced display devices mainly use a mixture of red, green, and blue light-emitting devices to produce white light or achieve full-color display. However, in mass-produced display devices, the blue light-emitting device primarily uses a TTF (Total Fluorescent Filament) substrate and a fluorescent blue light-emitting substrate to improve luminous efficiency and ensure production lifespan. For mass-produced red and green light-emitting devices, phosphorescence technology is used. Currently, AMOLEDs are not only used in mobile phones but are also gradually entering the fields of computer screens, foldable screens, and automotive displays. However, depending on the usage scenario, the ambient temperature in different scenarios has varying effects on the efficiency of AMOLED's various color light-emitting devices.

[0053] In the following description of the embodiments disclosed herein, blue is used as the first color, green as the second color, and red as the third color for illustration. Figure 1 The curves showing the change in the current efficiency ratios of the first-color, second-color, and third-color light-emitting devices as operating temperature increases are shown below. Figure 1 As shown, 25℃ is defined as the reference temperature, and J = 15mA / cm. 2 The absolute value of the current efficiency of the light-emitting device, measured using the reference current density, is taken as the reference current efficiency; with J = 15 mA / cm². 2The absolute value of the current efficiency at different operating temperatures under the given conditions is taken as the operating current efficiency, and the percentage of the operating current efficiency to the reference current efficiency is taken as the current efficiency ratio. With the current efficiency ratio as the ordinate and the operating temperature as the abscissa, the curves showing the change of the current efficiency ratio of the first, second, and third color light-emitting devices at different temperatures under the reference current density conditions are obtained. The current efficiency ratio of the first color light-emitting device increases with increasing temperature, increasing by approximately 3% to 10%, while the current efficiency ratios of the second and third color light-emitting devices decrease with increasing temperature. The current efficiency ratio of the second color light-emitting device is approximately between 3% and 10%, and that of the third color light-emitting device is approximately between 6% and 15%. When the current efficiency ratios of the first and third color light-emitting devices differ significantly within the same operating temperature, or when the current efficiency ratios of the first and second color light-emitting devices differ significantly within the same operating temperature, the display effect will appear bluish or yellowish, affecting the visual effect.

[0054] Figure 2 The curve shows the ratio of the current efficiency of the first-color light-emitting device to that of the second-color light-emitting device as a function of increasing operating temperature. Figure 3 The curves showing the ratio of the current efficiency of the first-color and third-color light-emitting devices as a function of increasing operating temperature are shown below. Figure 2 , 3 As shown, in the display, when the operating temperature changes, the curves of the current efficiency ratio of the first color light-emitting device and the second color light-emitting device tend to converge (arrow direction), making it less likely for color differences to occur in the display due to changes in operating temperature; the curves of the current efficiency ratio of the first color light-emitting device and the third color light-emitting device tend to converge (arrow direction), making it less likely for color differences to occur in the display due to changes in operating temperature.

[0055] Taking the currently mass-produced AMOLED display device as an example, the light-emitting layer material of the first color light-emitting device is a combination of a host material and a blue fluorescent guest material. The light-emitting layer materials of the third color light-emitting device and the second color light-emitting device both include phosphorescent materials. Therefore, when facing the ambient temperature in different scenarios, the current efficiency of the first color light-emitting device, the second color light-emitting device and the third color light-emitting device will change differently, thus producing color difference.

[0056] In view of this, the present disclosure provides a display substrate in which the light-emitting layer material of the first color light-emitting device satisfies the condition that the current efficiency ratio increases or decreases monotonically with the change of operating temperature, and the light-emitting layer materials of the second and third color light-emitting devices satisfy the condition that the change curve of the current efficiency ratio decreases monotonically with the increase of operating temperature; and, at the first operating temperature, the product of the difference in the current efficiency ratio between the first and third color light-emitting devices and the difference between the first operating temperature and the reference temperature ranges from 0 to 21.6; the product of the difference in the current efficiency ratio between the first and second color light-emitting devices and the difference between the first operating temperature and the reference temperature ranges from 0 to 15.4; the product of the difference in the current efficiency ratio between the first and third color light-emitting devices and the difference between the first operating temperature and the reference temperature ranges from 0 to 11; and the product of the difference in the current efficiency ratio between the first and second color light-emitting devices and the difference between the first operating temperature and the reference temperature ranges from 0 to 8.2 at the second operating temperature.

[0057] The display substrate provided in the embodiments of this disclosure will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0058] In a first aspect, embodiments of the present disclosure provide a display substrate, which includes a substrate and a first color light-emitting device D1, a second color light-emitting device D2 and a third color light-emitting device D3 disposed on the substrate. Figure 4 This is a schematic diagram of a display substrate provided in an embodiment of the present disclosure. Figures 5a-5d The curve showing the change of current efficiency ratio as a function of operating temperature provided in the embodiments of this disclosure is as follows: Figure 4 , 5a As shown in Figure -5d, under the condition of a reference current density, a coordinate system is established with the operating temperature as the horizontal axis and the current efficiency ratio as the vertical axis. The material of the emissive layer EML of the first color light-emitting device D1 satisfies the condition that the current efficiency ratio increases or decreases monotonically with increasing operating temperature when the first color light-emitting device D1 emits light. The materials of the emissive layer EML of the third color light-emitting device D3 and the emissive layer EML of the second color light-emitting device D2 satisfy the condition that the current efficiency ratio decreases monotonically with increasing operating temperature when the third color light-emitting device D3 and the second color light-emitting device D2 emit light. Here, the current efficiency ratio is the percentage of the operating current efficiency to the reference current efficiency. The reference current density is 15 mA / cm². 2Taking a reference temperature of 25℃ as an example, the first operating temperature is 45℃, which is higher than the reference temperature by a difference of 20℃. The second operating temperature is -10℃, which is lower than the reference temperature by a difference of 35℃. When the first color light-emitting device D1, the second color light-emitting device D2, and the third color light-emitting device D3 emit light at the reference temperature, their operating current efficiencies are the reference current efficiencies.

[0059] It should be noted that the embodiments disclosed herein do not further specify the pixel driving circuit for driving the light-emitting devices, nor the first color light-emitting device D1, the second color light-emitting device D2, and the third color light-emitting device D3. Figure 1 The arrangement of light-emitting devices in the image is merely an example.

[0060] like Figure 5a As shown, when the first color light-emitting device D1 and the second color light-emitting device D2 are operating at the first operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the second color light-emitting device D2 and the difference between the first operating temperature and the reference temperature ranges from 0 to 8.2. Figure 5a As shown, by controlling the material of the first color light-emitting layer EML of the first color light-emitting device D1, the area S1 enclosed by points A, B, and C is in the range of 0-4.1. When the temperature rises during display, the current efficiency of the first color light-emitting device D1 and the second color light-emitting device D2 will not change too much due to temperature changes, so as not to cause a large difference in the current efficiency of the first color light-emitting device D1 and the second color light-emitting device D2, resulting in color difference in the display.

[0061] like Figure 5b As shown, when the first color light-emitting device D1 and the second color light-emitting device D2 are operating at the second operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the second color light-emitting device D2 and the difference between the first operating temperature and the reference temperature ranges from 0 to 15.4. Figure 5b As shown, by controlling the material of the first color light-emitting layer EML of the first color light-emitting device D1, the area S2 enclosed by points D, E, and G is in the range of 0-7.7. When the display is on, the temperature decreases, and the current efficiency of the first color light-emitting device D1 and the second color light-emitting device D2 will not change too much due to temperature changes, so as not to cause a large difference in the current efficiency of the first color light-emitting device D1 and the second color light-emitting device D2, resulting in color difference in the display.

[0062] like Figure 5cAs shown, when the first color light-emitting device D1 and the third color light-emitting device D3 are operating at the first operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the third color light-emitting device D3 and the difference between the first operating temperature and the reference temperature ranges from 0 to 11. Figure 5c As shown, by controlling the material of the first color light-emitting layer EML of the first color light-emitting device D1, the area S3 enclosed by points O, P, and Q is in the range of 0-5.5. When the temperature rises during display, the current efficiency of the first color light-emitting device D1 and the third color light-emitting device D3 will not change too much due to temperature changes, so as not to cause a large difference in the current efficiency of the first color light-emitting device D1 and the third color light-emitting device D3, resulting in color difference in the display.

[0063] like Figure 5d As shown, when the first color light-emitting device D1 and the third color light-emitting device D3 are operating at the second operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the third color light-emitting device D3 and the difference between the first operating temperature and the reference temperature ranges from 0 to 21.6. Figure 5d As shown, by controlling the material of the first color light-emitting layer EML of the first color light-emitting device D1, the area S4 enclosed by points X, Y, and Z is in the range of 0-10.8. When the display is performed, the temperature decreases, and the current efficiency of the first color light-emitting device D1 and the third color light-emitting device D3 will not change too much due to temperature changes, so as not to cause a large difference in the current efficiency of the first color light-emitting device D1 and the third color light-emitting device D3, resulting in color difference in the display.

[0064] It should be noted that, Figures 5a-5d As an exemplary coordinate graph, the light-emitting layer materials of the first color light-emitting device D1, the second color light-emitting device D2, and the third color light-emitting device D3 are different, and their corresponding current efficiency ratios change curves with increasing operating temperature are different. Area S1 is the area of ​​the triangle obtained by dividing the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the second color light-emitting device D2 by the difference between the first operating temperature and the reference temperature by two; Area S2 is the area of ​​the triangle obtained by dividing the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the second color light-emitting device D2 by the difference between the second operating temperature and the reference temperature by two; Area S3 is the area of ​​the triangle obtained by dividing the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the third color light-emitting device D3 by the difference between the first operating temperature and the reference temperature by two; Area S4 is the area of ​​the triangle obtained by dividing the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the third color light-emitting device D3 by the difference between the second operating temperature and the reference temperature by two. Figure 2 , 3In 5a-5d, the curves showing a monotonically increasing trend are the curves showing the change in the current efficiency ratio of the first color light-emitting device D1 as the operating temperature increases.

[0065] In this embodiment, the specific materials of the emissive layer EML of the first color light-emitting device D1 are provided. The first color light-emitting device D1 includes a first color emissive layer EML sandwiched between a first electrode 101 and a second electrode 102. The materials of the first color emissive layer EML include a hole-type host material, an electron-type host material, and a doping material. The hole-type host material of the first color emissive layer EML includes a silicon-containing compound; the electron-type host material of the first color emissive layer EML includes a triazine-containing compound. The doping material of the first color emissive layer EML includes: a platinum-containing phosphorescent material, or a superfluorescent material with an energy difference of less than 0.3 eV between the lowest singlet state and the lowest triplet state.

[0066] The following embodiments provide a detailed description of the material of the first color emitting layer EML of the first color emitting device D1.

[0067] Example 1:

[0068] The first color light-emitting device D1 includes a first electrode 101, a second electrode 102, and a sandwiched first color light-emitting layer EML. The first color light-emitting layer EML material is composed of a hole-type host material, an electron-type host material, and a dopant material. The hole-type host material includes silicon-containing compounds, and the electron-type host material includes triazine-containing compounds. The dopant material is a platinum-containing phosphorescent material with the following chemical formula:

[0069] in,

[0070] M is platinum; X1 is carbon, and the bond between X1 and M is covalent; X2 is carbon, and the bond between X2 and M is covalent; X3 is carbon or nitrogen, and the bond between X3 and M is covalent; X4 is nitrogen, and the bond between X4 and M is covalent. CY2, CY3, and CY4 are all independently C3-C. 60 Carbocyclic or C1-C 60 Heterocyclic groups; L1, L2, and L3 are each independently a single bond or a bridging group. R1, R2, R3, R4, and R 11 In this group, at least one is hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C2-C 60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C 60 Aryloxy group, unsubstituted or substituted C6-C 60 Any functional group in the arylthioyl group. Y1 and Y2 are both independently C or N, and the dashed line connecting them to X1 represents a double bond. a1, a2, and a3 are all independently 1, 2, or 3, where a1 represents the number of L1, a2 represents the number of L2, and a3 represents the number of L3. b1 is 1 or 2, and b2, b3, and b4 are all independently integers from 1 to 10, where b1 represents the number of R1, b2 represents the number of R2, b3 represents the number of R3, and b4 represents the number of R4.

[0071] In some examples, the chemical formula of the doped material of the first color emitting layer EML includes R1, R2, R3, R4, and R... 11 Each of these groups is independently hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C2-C 60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C 60 Aryloxy group, unsubstituted or substituted C 6- C 60 Any functional group in the arylthio group.

[0072] In some examples, the chemical formula of the doped material of the first color emitting layer EML includes R1, R2, R3, R4, and R... 11 It may also include *-Si(R5)(R6)(R7), *-N(R5)(R6), *-B(R5)(R6), *-C(=O)(R5), *-S(=O)2(R5), or *-P(=O)(R5)(R6). Wherein, R5, R6, and R7 are each independently hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C 2-C60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C60 Aryloxy group, unsubstituted or substituted C6-C 60 Any functional group in the arylthio group.

[0073] Furthermore, in the chemical formula of the doping material of the first color emitting layer (EML), at least two of R1, R2, R3, R4, R5, and R6 are combined to form unsubstituted or substituted C3-C. 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group.

[0074] In some examples, when L1, L2, and L3 are bridging groups in the chemical formula of the doped material of the first color emitting layer EML, L1 to L3 are each independently *-O-*', *-S-*', *-Se-*', *-S(=O)2-*', *-C(R5)(R6)-*', *-C(R5)=*', *=C(R5)-*', *-C(R5)=C(R6)-*', *-C(=O)-*', *-C(=S)-*', *-C≡C-*', *-B(R5)-*', *-N(R5)-*', *-P(R5)-*', *-Si(R5)(R6)-*', *-P(=O)(R5)-*', or *-Ge(R5)(R6)-*'.

[0075] In some examples, the chemical structure of the hole-type host material in the first color emitting layer EML of the first color emitting device D1 is as follows:

[0076]

[0077] The electronic structure of the host material is as follows:

[0078]

[0079] The chemical structure of the doped material is as follows:

[0080]

[0081] In Example 1, Figure 8 This is a schematic diagram of the stacked structure of the light-emitting device provided in the embodiments of this disclosure, as shown below. Figure 8As shown, the structure of the first color light-emitting device D1 consists of, in sequence, a first electrode 101, a hole injection layer HIL, a hole transport layer HTL, an electron blocking layer EBL, a first color light-emitting layer EML, a hole blocking layer HBL, an electron transport layer ETL, an electron injection layer EIL, and a second electrode 102. The first electrode 101 is fabricated using a micro-stacked structure, with an Ag layer sandwiched between two ITO layers. The thickness of the ITO is 5 nm to 15 nm, and the thickness of the Ag is 50 nm to 100 nm. The hole injection layer HIL and the hole transport layer HTL use the same host material. The hole injection layer HIL is doped with 0.1% to 5% P-type material, and its thickness is 8 nm to 20 nm. The thickness of the hole transport layer HTL is 60 nm to 150 nm. The thickness of the electron blocking layer EBL is 5 nm to 10 nm. The first color emitting layer (EML) material uses the aforementioned compounds, including silicon-containing compounds as the hole-type host material, triazine-containing compounds as the electron-type host material, and platinum-containing phosphorescent materials as dopants. The thickness of the first color emitting layer (EML) is 20 nm to 45 nm, with the doping concentration of the dopant material ranging from 5% to 20%. The hole blocking layer (HBL) has a thickness of 5 nm to 15 nm. The electron transport layer (ETL) material has a thickness of 25 nm to 45 nm and is doped with LIF based on the host material. The hole injection layer (HIL) uses Yb, LIF, or LIQ as the material. The second electrode 102 uses a Mg / Ag alloy with a thickness of 13 nm to 25 nm and a Mg / Ag ratio of 5:5 to 1:9.

[0082] In the second color emitting layer EML of the second color emitting device D2, the chemical structure of the hole-type host material is as follows:

[0083]

[0084] The electronic structure of the host material is as follows:

[0085]

[0086] The chemical structure of the doped material is as follows:

[0087]

[0088] In the third color emitting layer EML of the third color emitting device D3, the chemical structure of the hole-type host material is as follows:

[0089]

[0090] The electronic structure of the host material is as follows:

[0091]

[0092] The chemical structure of the doped material is as follows:

[0093]

[0094] In Example 1, Figure 6 The curves showing the change in the current efficiency ratio of the first, second, and third color light-emitting devices in Example 1 as the operating temperature increases are shown below. Figure 6 As shown, the current efficiency ratios of the first-color light-emitting device D1, the second-color light-emitting device D2, and the third-color light-emitting device D3 all exhibit a monotonically decreasing trend with increasing operating temperature. The first operating temperature is 45 degrees Celsius, and the second operating temperature is -10 degrees Celsius. At the first operating temperature, the product of the difference in the current efficiency ratio between the first-color light-emitting device D1 and the second-color light-emitting device D2 and the difference between the first operating temperature and the reference temperature is approximately 0.48, and the product of the difference in the current efficiency ratio between the first-color light-emitting device D1 and the third-color light-emitting device D3 and the difference between the first operating temperature and the reference temperature is approximately 0.94. At the second operating temperature, the product of the difference in the current efficiency ratio between the first-color light-emitting device D1 and the second-color light-emitting device D2 and the difference between the first operating temperature and the reference temperature is approximately 0.61, and the product of the difference in the current efficiency ratio between the first-color light-emitting device D1 and the third-color light-emitting device D3 and the difference between the first operating temperature and the reference temperature is approximately 0.76.

[0095] Example 2:

[0096] The first color emitting layer (EML) material of the first color emitting device D1 consists of a hole-type host material, an electron-type host material, and a dopant material. The dopant material is a superfluorescent material with the following chemical formula:

[0097]

[0098] The general chemical formula of the cavitation-type host material is:

[0099]

[0100] The general chemical formula of the electronic host material is:

[0101]

[0102] In Example 2, Figure 7 The curves showing the change in the current efficiency ratio of the first, second, and third color light-emitting devices in Example 2 as the operating temperature increases are shown below. Figure 7As shown, the doping material in the first-color emitting layer EML material of the first-color emitting device D1 in Example 1 is replaced with a superfluorescent material. The second-color emitting layer EML material of the second-color emitting device D2 and the third-color emitting layer EML material of the third-color emitting device D3 are the same as in Example 1. The current efficiency ratios of the first-color emitting device D1, the second-color emitting device D2, and the third-color emitting device D3 all exhibit a monotonically decreasing trend with increasing operating temperature. The first operating temperature is 45 degrees Celsius, and the second operating temperature is -10 degrees Celsius. At the first operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the second color light-emitting device D2 and the difference between the first operating temperature and the reference temperature is approximately 0.56, and the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the third color light-emitting device D3 and the difference between the first operating temperature and the reference temperature is approximately 0.74; at the second operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the second color light-emitting device D2 and the difference between the first operating temperature and the reference temperature is approximately 0.84; and the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the third color light-emitting device D3 and the difference between the first operating temperature and the reference temperature is approximately 1.02.

[0103] Example 1 0.24 0.47 0.31 0.38 Example 2 0.28 0.37 0.42 0.51 Comparative Example 1 2.1 3.7 2.9 5.4

[0104] Table 1

[0105] Table 1 shows the areas S1, S2, S3, and S4 enclosed by the curves showing the change in the current efficiency ratio of the first color light-emitting device D1, the second color light-emitting device D2, and the third color light-emitting device D3 as the operating temperature increases in Examples 1, 2, and Comparative Example 1. Comparing Examples 1 and 2 with Comparative Example 1, the first color pixel unit in Comparative Example 1 uses the existing first color light-emitting layer EML material, the first operating temperature is 45 degrees Celsius, and the second operating temperature is -10 degrees Celsius. At the first operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the second color light-emitting device D2 and the difference between the first operating temperature and the reference temperature is approximately 4.2, corresponding to an area S1 of 2.1. The product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the third color light-emitting device D3 and the difference between the first operating temperature and the reference temperature is approximately 7.4, corresponding to an area S2 of 3.7. At the second operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the second color light-emitting device D2 and the difference between the first operating temperature and the reference temperature is approximately 5.8, corresponding to an area S3 of 2.9. The product of the difference in the current efficiency ratio between the first color light-emitting device D1 and the third color light-emitting device D3 and the difference between the first operating temperature and the reference temperature is approximately 10.8, corresponding to an area S4 of 5.4. Compared with Examples 1 and 2, the light-emitting layer EML of the light-emitting device in Comparative Example 1 is more affected by temperature. Therefore, by changing the material of the first color light-emitting layer EML, the influence of temperature on the current efficiency of the first color light-emitting device D1 is significantly reduced, and the display is less prone to color shift when the temperature changes.

[0106] It should be noted that Examples 1 and 2 are only two specific examples. The EML material of the first color light-emitting device D1 can also be other types of materials or materials with other chemical structures. Furthermore, the EML materials of the second color light-emitting device D2 and the third color light-emitting device D3 can be adjusted. For example, the EML materials of the first color light-emitting device D1, the second color light-emitting device D2, and the third color light-emitting device D3 can all be doped with superfluorescent materials; the EML materials of the first color light-emitting device D1 and the third color light-emitting device D3 can all be doped with superfluorescent materials; and the EML materials of the second color light-emitting device D2 can all be doped with phosphorescent materials, etc. The following conditions must be met: at the first operating temperature, the product of the difference in the current efficiency ratio between the first and second color light-emitting devices D1, D2, and D3, and the difference between the first operating temperature and the reference temperature, must be within the range of 0-8.2; at the second operating temperature, the product of the difference in the current efficiency ratio between the first and second color light-emitting devices D1 and D2, and the difference between the first operating temperature and the reference temperature, must be within the range of 0-11; at the third operating temperature, the product of the difference in the current efficiency ratio between the first and second color light-emitting devices D2, and the difference between the first operating temperature and the reference temperature, must be within the range of 0-15.4; at the fourth operating temperature, the product of the difference in the current efficiency ratio between the first and third color light-emitting devices D1 and D3, and the difference between the first operating temperature and the reference temperature, must be within the range of 0-21.6. The first operating temperature is 45 degrees Celsius, and the second operating temperature is -10 degrees Celsius. The curves showing the ratio of the current efficiency of the first-color light-emitting device D1, the second-color light-emitting device D2, and the third-color light-emitting device D3 as a function of operating temperature can be either monotonically increasing or monotonically decreasing. It is also understandable that these can be stacked light-emitting devices, meaning a single light-emitting device with multiple light-emitting layers (EMLs).

[0107] This disclosure also provides a display device comprising the display substrate described in any of the above embodiments. The display device can be, for example, any product with a display function such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or in-vehicle device. Other essential components of this display device are readily understood by those skilled in the art and will not be described in detail here, nor should they be construed as limiting the scope of this disclosure.

[0108] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A display substrate, characterized in that, include: A substrate, wherein a first-color light-emitting device, a second-color light-emitting device, and a third-color light-emitting device are disposed on the substrate; wherein... The light-emitting layer materials of the first color light-emitting device, the second color light-emitting device, and the third color light-emitting device satisfy the following conditions: When the first color light-emitting device, the second color light-emitting device, and the third color light-emitting device emit light, the current efficiency ratio of the first color light-emitting device increases or decreases monotonically with increasing operating temperature; the current efficiency ratios of the second color light-emitting device and the third color light-emitting device decrease monotonically with increasing operating temperature. When the first color light-emitting device and the second color light-emitting device are operating at the first operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device and the second color light-emitting device and the difference between the first operating temperature and the reference temperature ranges from 0 to 8.

2. When the first color light-emitting device and the second color light-emitting device are operating at the second operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device and the second color light-emitting device and the difference between the first operating temperature and the reference temperature ranges from 0 to 15.

4. When the first color light-emitting device and the third color light-emitting device are operating at the first operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device and the third color light-emitting device and the difference between the first operating temperature and the reference temperature is in the range of 0-11. When the first color light-emitting device and the third color light-emitting device are operating at the second operating temperature, the product of the difference in the current efficiency ratio between the first color light-emitting device and the third color light-emitting device and the difference between the first operating temperature and the reference temperature ranges from 0 to 21.6; where, The first operating temperature is greater than the reference temperature, and the second operating temperature is less than the reference temperature.

2. The display substrate according to claim 1, characterized in that, The reference temperature is 25 degrees Celsius, the first operating temperature is 45 degrees Celsius, and the second operating temperature is -10 degrees Celsius.

3. The display substrate according to claim 1, characterized in that, The first color light-emitting device includes a first color light-emitting layer sandwiched between a first electrode and a second electrode; The material of the first color emitting layer includes a hole-type host material, an electron-type host material, and a doped material; The hole-type host material of the first color emitting layer includes a silicon-containing compound material; the electron-type host material of the first color emitting layer includes a triazine-containing compound. The doping material of the first color emitting layer includes: a phosphorescent material containing platinum, or a superfluorescent material with an energy difference of less than 0.3 eV between the lowest singlet state and the lowest triplet state.

4. The display substrate according to claim 3, characterized in that, When the doping material of the first color emitting layer is a platinum-containing phosphorescent material, the general chemical formula of the doping material is: in, M is platinum; X1 is carbon, and the bond between X1 and M is a covalent bond; X2 is carbon, and the bond between X2 and M is a covalent bond; X3 is carbon or nitrogen, and the bond between X3 and M is a covalent bond; X4 is nitrogen, and the bond between X4 and M is a covalent bond. CY2, CY3, CY4are each independently C3-C 60 carbocyclyl or C1-C 60 heterocyclyl; L1, L2, L3are each independently a single bond or a bridging group; R1, R2, R3, R4 and R 11 In this group, at least one is hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C2-C 60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C 60 Aryloxy group, unsubstituted or substituted C6-C 60 Any functional group in the arylthio group; among which, a1, a2, and a3 are all independent and can be 1, 2, or 3; b1 is either 1 or 2, and b2, b3 and b4 are all independent integers from 1 to 10.

5. The display substrate according to claim 4, characterized in that, In the chemical formula of the doped material of the first color emitting layer, R1, R2, R3, R4 and R 11 Each of these groups is independently hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C2-C 60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C 60 Aryloxy group, unsubstituted or substituted C 6- C 60 Any functional group in the arylthio group.

6. The display substrate according to claim 4, characterized in that, In the chemical formula of the doped material of the first color emitting layer, R1, R2, R3, R4 and R 11 It may also include *-Si(R5)(R6)(R7), *-N(R5)(R6), *-B(R5)(R6), *-C(=O)(R5), *-S(=O)2(R5), or *-P(=O)(R5)(R6); where, R5, R6, and R7 are all independently hydrogen, deuterium, fluorine, chlorine, bromine, iodine, hydroxyl, cyano, nitro, unsubstituted or substituted C1-C. 60 Alkyl, unsubstituted or substituted C 2-C60 Alkenyl, unsubstituted or substituted C2-C 60 Alkyne group, unsubstituted or substituted C1-C 60 Alkyl group, unsubstituted or substituted C3-C 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group, unsubstituted or substituted C6-C 60 Aryloxy group, unsubstituted or substituted C6-C 60 Any functional group in the arylthio group.

7. The display substrate according to any one of claims 4-6, characterized in that, In the chemical formula of the doped material of the first color emitting layer, at least two of R1, R2, R3, R4, R5, and R6 are combined to form unsubstituted or substituted C3-C. 60 Carbocyclic group, unsubstituted or substituted C1-C 60 Heterocyclic group.

8. The display substrate according to claim 4, characterized in that, In the chemical formula of the doped material of the first color emitting layer, when L1, L2, and L3 are bridging groups, L1 to L3 are each independently *-O-*', *-S-*', *-Se-*', *-S(=O)2-*', *-C(R5)(R6)-*', *-C(R5)=*', *=C(R5)-*', *-C(R5)=C(R6)-*', *-C(=O)-*', *-C(=S)-*', *-C≡C-*', *-B(R5)-*', *-N(R5)-*', *-P(R5)-*', *-Si(R5)(R6)-*', *-P(=O)(R5)-*', or *-Ge(R5)(R6)-*'.

9. The display substrate according to claim 4, characterized in that, When the doping material of the first color emitting layer is a platinum-containing phosphorescent material, its general chemical formula is:

10. The display substrate according to claim 3, characterized in that, In the first color light-emitting device, when the doping material in the first color light-emitting layer is a superfluorescent material, its chemical formula is:

11. The display substrate according to claim 3, characterized in that, When the doping material of the first color emitting layer is a platinum-containing phosphorescent material, the general chemical formula of the hole-type host material is: The general chemical formula of the electronic host material is:

12. The display substrate according to claim 3, characterized in that, When the doping material of the first color emitting layer is a superfluorescent material, the general chemical formula of the hole-type host material is: The general chemical formula of the electronic host material is:

13. A display device comprising a display substrate as described in any one of claims 1-12.

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