Design of CPRTP materialsSodium cellulose trimellitate (CBtCOONa) and sodium carboxymethyl cellulose (CMCNa) were chosen as polymer matrix to achieve circularly polarized luminescence. After mixing CBtCOONa or CMCNa with water-soluble luminophores in aqueous solution and then evaporating the solvent, CPRTP materials were obtained (Fig. 1). Left circularly polarized phosphorescence materials (L-CPRTP) were obtained when CBtCOONa was used as a substrate; right circularly polarized phosphorescent materials (R-CPRTP) were obtained when CMCNa was used as a substrate. These phenomena derive from contrary helical structures of anionic cellulose derivatives with different chemical structures. Furthermore, full-color CPRTP materials were achieved with emission wavelengths of 420–630 nm via regulating the chemical structures and aggregation states of luminophores.Fig. 1: Responsive full-color CPRTP materials from natural cellulose.Schematic illustration and Commission Internationale d’Eclairage (CIE) coordinate diagram of full-color CPRTP materials. Left circularly polarized phosphorescence materials (L-CPRTP) were obtained when CBtCOONa was used as a substrate; right circularly polarized phosphorescent materials (R-CPRTP) were obtained when CMCNa was used as a substrate.Performance of CPRTP materialsThe as-prepared CPRTP materials were investigated in detail using lithium 1,4,5,8-naphthalenetetracarboxylic (NtCOOLi)/CBtCOONa and NtCOOLi/CMCNa as examples. NtCOOLi/CBtCOONa emits L-CPRTP with an emission peak at 570 nm (Fig. 2a), and the strongest L-CPRTP performance is achieved with a NtCOOLi content of 1.0 wt%. Fluorescence emission peak of NtCOOLi/CBtCOONa is at 425 nm (Supplementary Fig. 1). The phosphorescence emission of NtCOOLi/CBtCOONa exhibits NtCOOLi-content dependence, excitation-wavelength dependence and time dependence (Fig. 2b–d, and Supplementary Fig. 2). For example, NtCOOLi/CBtCOONa with a NtCOOLi content of 0.01 wt% has two phosphorescence peaks at 470 nm and 518 nm under 254–310 nm excitation; three phosphorescence peaks (470 nm, 535 nm and 565 nm) under 340 nm excitation; and three phosphorescence peaks (515 nm, 570 nm and 616 nm) under 365 nm excitation. NtCOOLi/CBtCOONa with NtCOOLi contents of 0.1 wt%-1.0 wt% emits two phosphorescence peaks at 527 nm and 568 nm under 254–310 nm excitation; two phosphorescence peaks at 535 nm and 568 nm under 340 nm excitation; and two phosphorescence peaks at 568 nm and 615 nm under 365 nm excitation. NtCOOLi/CBtCOONa with NtCOOLi content of 10 wt%–40 wt% emits two phosphorescence peaks at 533 nm and 572 nm under 254–340 excitation; and two phosphorescence peaks at 572 nm and 620 nm under 365 nm excitation. The lifetimes of two phosphorescence peaks at 520 nm and 570 nm of NtCOOLi/CBtCOONa with a NtCOOLi content of 1.0 wt% are 175 ms and 151 ms, respectively (Supplementary Fig. 3). These phenomena suggest that NtCOOLi/CBtCOONa has multiple emission centers which are related to a variety of aggregation states of NtCOOLi. In addition, as the content of NtCOOLi increases from 1.0 wt% to 10 wt%, the phosphorescence peaks of NtCOOLi/CBtCOONa show an obvious red-shift with a reduced lifetime (Fig. 2b, c, and Supplementary Fig. 4). The results indicate that NtCOOLi forms larger aggregates in the CBtCOONa matrix as the concentration of NtCOOLi increases. NtCOOLi/CBtCOONa with a NtCOOLi content of 0.01 wt% exhibits green phosphorescence and yellow phosphorescence with 310 nm and 365 nm lamps off, respectively (Supplementary Fig. 5). NtCOOLi/CBtCOONa with a NtCOOLi content of 1.0 wt% has a yellow phosphorescence after turning off 310 nm lamp, then the emission gradually changes to green phosphorescence with the time extension (Fig. 2d). Meanwhile, this material exhibits an orange-yellow phosphorescence after turning off 365 nm lamp, then the emission gradually changes to orange phosphorescence as the time increases. The |glum| is 0.6 × 10-2. NtCOOLi/CBtCOONa with a NtCOOLi content of 10 wt% exhibits a yellow phosphorescence after turning off 310 nm lamp, then the emission gradually changes to orange-yellow phosphorescence as the time increases (Fig. 2d). It exhibits an orange-yellow phosphorescence after turning off 365 nm lamp, then the emission gradually changes to orange phosphorescence with the time extension. These phenomena indicate the phosphorescence emission of NtCOOLi/CBtCOONa is time-dependent. It is worth noting that NtCOOLi/CBtCOONa has a visible-light excitation phosphorescence performance. Under 400–440 nm excitation, NtCOOLi/CBtCOONa has wide phosphorescence emission at 500–700 nm (Supplementary Fig. 2). After a visible-light excitation, NtCOOLi/CBtCOONa with NtCOOLi contents of 1.0 wt%–10 wt% shows an apparent phosphorescence, which can be directly observed by the naked eye and lasts up to 1.6 s (Fig. 2d). All these results indicate that NtCOOLi/CBtCOONa has a L-CPRTP property with concentration-dependence, excitation-dependence, time-dependence and visible excitation properties.Fig. 2: CPRTP performance of NtCOOLi/CBtCOONa and NtCOOLi/CMCNa.a CPL spectra of NtCOOLi/CBtCOONa with NtCOOLi contents of 0.1%–2.0%. b, c Phosphorescence excitation and emission spectra of NtCOOLi/CBtCOONa with 1% and 10% NtCOOLi contents. d Photographs of NtCOOLi/CBtCOONa with different NtCOOLi contents under irradiation with different lamps and the lamps off. e CPL spectra of NtCOOLi/CMCNa with NtCOOLi content of 0.1%–2.0%. f, g Phosphorescence excitation and emission spectra of NtCOOLi/CMCNa with 1% and 10% NtCOOLi content. h Photographs of NtCOOLi/CMCNa with different NtCOOLi contents under irradiation with different lamps and the lamps off.NtCOOLi/CMCNa emits right circularly polarized phosphorescence (R-CPRTP) at 540 nm (Fig. 2e). NtCOOLi/CMCNa with a NtCOOLi content of 1.0 wt% has the strongest R-CPRTP performance. The fluorescence peak of NtCOOLi/CMCNa with NtCOOLi contents of 0.01 wt%–1.0 wt% emerges at 396 nm, and that of NtCOOLi/CMCNa with NtCOOLi contents of 10 wt%–50 wt% is at 407 nm (Supplementary Fig. 6). The phosphorescence emission of NtCOOLi/CMCNa exhibits NtCOOLi concentration-dependence, excitation wavelength-dependence, time-dependence and visible-light excitation properties (Fig. 2f–h, and Supplementary Fig. 7). NtCOOLi/CMCNa with a NtCOOLi content of 0.01 wt% has three phosphorescence peaks (465 nm, 524 nm and 556 nm) under 254–310 nm excitation; two phosphorescence peaks (483 nm and 535 nm) under 340 nm excitation; only one phosphorescence peak (512 nm) under 365 nm excitation. NtCOOLi/CMCNa with NtCOOLi contents of 0.1 wt%–1.0 wt% emits two phosphorescence peaks (531 nm and 559 nm) under 254–310 nm excitation; one phosphorescence peak (531 nm) under 340 nm excitation. NtCOOLi/CMCNa with a NtCOOLi content of 10 wt% has three phosphorescence peaks (532 nm, 572 nm and 617 nm) under 254–340 nm excitation; two phosphorescence peaks (572 nm and 617 nm) under 365 nm excitation. The lifetimes of two phosphorescence peaks (520 nm and 570 nm) of NtCOOLi/CMCNa with a NtCOOLi content of 1.0 wt% are 220 ms and 185 ms, respectively (Supplementary Fig. 8). In addition, when the contents of NtCOOLi increases from 1.0 wt% to 10 wt%, the phosphorescence peaks of NtCOOLi/CMCNa show a red-shift with a reduced lifetime (Fig. 2f, g, and Supplementary Fig. 9). NtCOOLi/CMCNa with a NtCOOLi content of 0.01 wt% exhibits a cyan phosphorescence with 254 nm and 310 nm lamps off, and has a green phosphorescence with 365 nm lamps off (Supplementary Fig. 10). NtCOOLi/CMCNa with a NtCOOLi content of 1.0 wt% exhibits a yellow phosphorescence after turning off 254 nm lamp, and the emission changes to a cyan phosphorescence as the time increases (Fig. 2h). It exhibits a yellow phosphorescence after turning off 365 nm lamp, then the emission changes to green phosphorescence gradually with the time extension. The |glum| reaches to 1.16 × 10−2. NtCOOLi/CMCNa with a NtCOOLi content of 10 wt% exhibits a yellow phosphorescence after turning off 310 nm lamp, and the emission changes to green phosphorescence as the time increases (Fig. 2h). It exhibits a yellow phosphorescence after turning off 365 nm lamp, and the emission changes to orange-red phosphorescence with time extension. These phenomena confirm that the phosphorescence of NtCOOLi/CMCNa is concentration-dependent, excitation wavelength-dependent, and time-dependent. Under visible-light excitation, NtCOOLi/CMCNa with a NtCOOLi content of 10 wt% shows an apparent white phosphorescence, which can be observed by the naked eye and lasts up to 0.8 s (Fig. 2h).Mechanism of CPRTPCircular dichroism (CD) spectra of CBtCOONa and CMCNa are measured with different degree of substitution (DS) to proclaim CPL mechanism. CD signals of CBtCOONa aqueous solution and film are negative, while those of CMCNa aqueous solution and film are positive (Fig. 3a, b, and Supplementary Fig. 11). Moreover, the higher the DS is, the stronger the CD signal is observed. By contrast, the pure cellulose (degree of polymerization (DP) = 8–10) and CBtCOONa with a low DS of 0.23 have negligible CD signals in aqueous solutions (Supplementary Fig. 12). The non-ionic cellulose derivatives are non-chiral in solutions also, including cellulose acetate (CA), cellulose acetate butyrate (CAB), ethyl cellulose (EC), hydroxypropyl cellulose (HPC) and hydroxypropyl methyl cellulose (HPMC) (Supplementary Fig. 13). In addition, the anionic cellulose derivative of sodium cellulose phthalate (CPhCOONa) exhibits a negative CD signal (Supplementary Fig. 13). These phenomena confirm that the electrostatic interactions between the ionic substituents in cellulose derivatives are essential in the formation of the helical structures. Scanning electron microscope (SEM) images show that both CBtCOONa film and CMCNa film are flat and dense (Supplementary Fig. 14), indicating that the CD signals originate from the helical structure of the anionic cellulose derivatives chains. Furthermore, we simulated the structure of three cellulose derivatives, including CBtCOONa, CMCNa and CA. The results indicate that the distance of substituent in adjacent repeating units is markedly different depending on the chemical structure of substituent. For CBtCOONa and CMCNa, the distances of substituent in adjacent repeating units are 17.36 Å and 10.36 Å, respectively, which are much higher than that of CA (9.33 Å) (Supplementary Fig. 15). The length of two adjacent repeating units in cellulose chain is 10 Å. Thus, the CBtCOONa and CMCNa chains would like to distort, and supply enough space to accommodate the anion substitutes. CBtCOONa and CMCNa chains with different negative charge groups form chiral helical structures in opposite directions, thus displaying contrary CD signals. The helical environment formed by CBtCOONa and CMCNa causes the luminophores to emit CPL (Fig. 3c, d). The higher the DS of CBtCOONa and CMCNa is, the stronger the electrostatic repulsive interactions among the polymer chains would be. As a result, those anionic cellulose derivatives which could form a chiral helical structure easily could be used to fabricate CPRTP materials with stronger CPL signals.Fig. 3: Mechanism of CPRTP.a, b CD spectra of CBtCOONa (DS = 0.49 and 1.38) and CMCNa (DS = 0.70 and 1.20) aqueous solutions. c, d CPL spectra of NtCOOLi/CBtCOONa and NtCOOLi/CMCNa containing 1% NtCOOLi, and CBtCOONa (CMCNa) with different DS. e, f Phosphorescence spectra of NtCOOLi aqueous solutions at 77 K (Ex = 310, 334 and 370 nm, delay time = 0.1 ms). g Delayed emission spectra of NtCOOLi/CBtCOONa film with a NtCOOLi content of 1% at 334 nm excitation with different delay time. h FTIR spectra of CBtCOONa, CMCNa, NtCOOLi/CBtCOONa and NtCOOLi/CMCNa with different NtCOOLi contents. i UV-vis spectra of CBtCOONa aqueous solution before and after adding NtCOOLi. j Fluorescence spectra of CBtCOONa, NtCOOLi and CBtCOONa/NtCOOLi aqueous solutions. k Phosphorescence mechanism of NtCOOLi/CBtCOONa and NtCOOLi/CMCNa.We further measured phosphorescence spectra of NtCOOLi aqueous solution at 77 K to investigate the phosphorescence mechanism (Fig. 3e, f). For 0.0001 mg/mL of NtCOOLi solution, a phosphorescence emission peak appears at 460 nm under 310 nm excitation, and three phosphorescence peaks are observed at 460 nm, 520 nm and 570 nm under 334 nm excitation (Fig. 3e). When the excitation wavelength is 370 nm, the phosphorescence peak at 460 nm disappears, and the strong phosphorescence emission emerges at 520 nm. For 50 mg/mL of NtCOOLi solution, three peaks emerge at 460 nm, 520 nm and 570 nm under 334 nm excitation, and the strongest emission peak appears at 570 nm (Fig. 3f). When the excitation wavelength is 370 nm, a phosphorescence emission peak appears at 613 nm. Delayed emission spectra of NtCOOLi/CBtCOONa film with a NtCOOLi content of 1 wt% at 334 nm excitation reveal that there are three phosphorescence emission peaks (Fig. 3g). With the increase of delay time, emission peaks at 530 nm and 610 nm gradually blue-shift, and their relatively intensities decrease. As the delay time increases from 10 ms to 361 ms, the phosphorescence emission peak at 570 nm blue-shifts to 565 nm. These phenomena indicate that NtCOOLi forms multiple phosphorescence emission states. The phosphorescence peak at 460 nm originates from a single molecule of NtCOOLi, and the phosphorescence peaks at 520 nm, 570 nm and 613 nm are attributed to the different aggregates of NtCOOLi. The larger the size of the NtCOOLi aggregate is, the longer the phosphorescence excitation and emission wavelengths would be. The various aggregation states of NtCOOLi results in NtCOOLi/CBtCOONa and NtCOOLi/CMCNa to be concentration-dependence, excitation wavelength-dependence, and time-dependence RTP performance.In order to further reveal the phosphorescence mechanism, NtCOOLi/PVA films were prepared. There are two phosphorescence peaks at 523 nm and 556 nm of NtCOOLi/PVA with 0.01 wt%–10 wt% NtCOOLi contents (Supplementary Figs. 16–17). When the NtCOOLi content increases to 50 wt%, the phosphorescence emission of NtCOOLi/PVA film changes significantly. The emission peak at 570 nm markedly enhances, and a distinct shoulder peak appears at 615 nm (Supplementary Fig. 16). Moreover, as the excitation wavelength increases from 280 nm to 380 nm, the phosphorescence peak at 530 nm disappears. The phosphorescence emission of NtCOOLi/PVA films shows concentration-dependence, excitation wavelength-dependence, and time-dependence also (Supplementary Fig. 18). These phenomena confirm that NtCOOLi forms different aggregation states, which display diverse phosphorescence emission (Supplementary Fig. 19).The interactions between NtCOOLi and CBtCOONa or CMCNa were explored. As the concentration of NtCOOLi increases, the stretching vibration peak of the hydroxyl groups in CBtCOONa and CMCNa shifts to a lower wavenumber, indicating that NtCOOLi forms strong hydrogen-bonding interactions with the hydroxyl groups in cellulose chains (Fig. 3h). In addition, after adding NtCOOLi into CBtCOONa aqueous solution, the absorbance peak at 245 nm shows a blue-shift (Fig. 3i), and the fluorescence peak shows a red-shift (Fig. 3j). Compared with NtCOOLi/CMCNa film and NtCOOLi/PVA film, the phosphorescence peaks of NtCOOLi/CBtCOONa film red-shift (Supplementary Fig. 20), confirming the formation of π-π interactions between NtCOOLi and CBtCOONa. Furthermore, after adding NtCOOLi into CBtCOONa solution, zeta potential changes from −55.1 mV to −62.7 mV (Supplementary Fig. 21), illustrating the electrostatic interaction between NtCOOLi and CBtCOONa. Therefore, the anionic cellulose derivatives, CBtCOONa and CMCNa, spontaneously form chiral helical structures. Meanwhile, they strongly interact with achiral luminophores, such as NtCOOLi, by hydrogen-bonding, electrostatic and π-π interactions, which transfer chirality to luminophores and suppress non-radiative transition. As a result, the CPRTP materials were fabricated, including both left and right CPRTP materials (Fig. 3k).Based on the above principle, multi-color CPRTP materials were prepared by adjusting the anionic cellulose derivatives and the achiral luminophores with different chemical structures and aggregation states. Lithium 2,6-naphthalenedicarboxylic (2,6-NdCOOLi)/CBtCOONa emits a green L-CPRTP with a long lifetime up to 936 ms (Supplementary Fig. 22). 1,4-Naphthalenedicarboxylic acid (1,4-NdCOOH)/CBtCOONa also emits a green L-CPRTP with a lifetime of 516 ms (Supplementary Fig. 23). Mellitic acid (MlCOOH)/CBtCOONa emits a yellow L-CPRTP, which changes into green phosphoresce after 1.2 s (Supplementary Fig. 24). 1-Anthracenecarboxylic acid (AnCOOH)/CBtCOONa and 1-pyrenecarboxylic acid (PyCOOH)/CBtCOONa give similar optical phenomena. The original yellow phosphorescence is transformed into green phosphorescence as the time increases (Supplementary Figs. 25–26). PyCOOH/CBtCOONa has a |glum| of 1.12 × 10−2. Rhodamine B (RhB)/CBtCOONa emits a left circularly polarized red afterglow (Supplementary Fig. 27).By mixing the above 6 kinds of luminophores with CMCNa, full-color R-CPRTP materials with the highest |glum| of 1.93 × 10−2 are obtained. The 2,6-NdCOOLi/CMCNa, 1,4-NdCOOLi/CMCNa and AnCOOLi/CMCNa have a green R-CPRTP with a long lifetime up to 708 ms (Supplementary Figs. 28–30). MlCOOLi/CMCNa emits a blue R-CPRTP with a lifetime of 139 ms (Supplementary Fig. 31). PyCOOLi/CMCNa emits a yellow R-CPRTP which gradually changes to green phosphorescence (Supplementary Fig. 32). RhB/CMCNa exhibits a right circularly polarized red afterglow (Supplementary Fig. 33). Therefore, a series of full-color CPRTP materials are obtained via controlling the anionic cellulose derivatives and the luminophores, with a wide color gamut from blue to yellow, green, orange and red.Processability and responsiveness of CPRTP materialsAnionic cellulose, CBtCOONa and CMCNa, with numerous ionic groups have excellent water solubility. Thus, via using an eco-friendly aqueous processing strategy and doping different luminophores, the flexible colorful RTP films with a large size can be obtained easily (Fig. 4a). Further, the resultant RTP films can be folded into different 3D objects (Fig. 4b). In addition, the CPRTP materials exhibit multi-responsive behaviors. Apart from the above excitation-dependence, time-dependence and visible-light excitation behaviors, the CPRTP materials display a significant response to the humidity, temperature and pH value. For example, the phosphorescence lifetime of CPRTP materials decreases after being stored in a high humidity environment (Fig. 4c). Surprisingly, the CPRTP materials remain a strong phosphorescence after being stored for 5 days in a 90% humidity environment, indicating a huge potential in the practical application. Moreover, as the environment temperature changes, phosphorescence appears and quenches reversibly (Fig. 4d). The CPRTP materials also exhibit a reversible pH-responsive behavior (Fig. 4e). Phosphorescence of the CPRTP materials obviously changes after a rapid treatment with acidic gas, such as HCl vapor. This is attributed to the carboxylate groups transforming into carboxylic acids after exposure to acid. The electrostatic interactions and hydrogen-bonding interactions are weakened in the CPRTP materials, and the interactions between cellulose chains and luminophores simultaneously change, resulting in color change or phosphorescence quenching. After exposure to alkaline gas, such as NH3·H2O vapor, the phosphorescence performance is restored.Fig. 4: Processability and responsiveness of CPRTP materials.a Optical images of CMCNa-based CPRTP films with a large size and different colors. b Fluorescence and phosphorescence images of 3D objects fabricated from 2,6-NdCOOLi/CMCNa film (Ex = 365 nm). c Humidity-responsive behavior of 2,6-NdCOOLi/CMCNa films (left) and NtCOOLi/CMCNa films (right) (Ex = 365 nm). d Temperature-responsive behavior of NtCOOLi/CMCNa film (Ex = 365 nm). e pH-responsive behavior of NtCOOLi/CBtCOONa, 2,6-NdCOOLi/CBtCOONa and RhB/CBtCOONa film (Ex = 365 nm). f Visual-recognition behavior of NtCOOLi/CMCNa and MlCOOLi/CMCNa (The third samples in the second row) for different enantiomers. g Visual-recognition behavior of NtCOOLi/CMCNa (left) and MlCOOLi/CMCNa (right) for different enantiomers.Interestingly, the CPRTP materials recognize many enantiomers in an instrument-free visual mode, including amino acids, hydroxyl acids, organic phosphate and hydrobenzoin (Fig. 4f, g, and Supplementary Fig. 34). They exhibited a obvious RTP color change, once meeting D-arginine/L-arginine, D-glutamine/L-glutamine, D-lysine/L-lysine, D-malic acid/L-malic acid, R-2-hydroxybutyric acid/S-2-hydroxybutyric acid, D-leucic acid/L-leucic acid, and R-1,1’-binaphthyl-2,2’-diyl hydrogenphosphate/S-1,1’-binaphthyl-2,2’-diyl hydrogenphosphate. For example, after adding D-arginine, the NtCOOLi/CMCNa shows yellow phosphorescence, while it exhibits green phosphorescence after the addition of L-arginine. After adding R-2-hydroxybutyric acid, the NtCOOLi/CMCNa shows yellow phosphorescence, while it exhibits orange phosphorescence after adding S-2-hydroxybutyric acid. After adding R-1,1’-binaphthyl-2,2’-diyl hydrogenphosphate, the NtCOOLi/CMCNa shows orange phosphorescence with a short lifetime, while it exhibits a time-dependence phosphorescence from yellow to green with a long phosphorescence lifetime after adding S-1,1’-binaphthyl-2,2’-diyl hydrogenphosphate. Besides, the CPRTP materials also displays a RTP lifetime change for hydrobenzoin enantiomers. After adding S,S-hydrobenzoin, the phosphorescence lifetime of the MlCOOLi/CMCNa is far longer than that of the sample with R,R-hydrobenzoin. Furthermore, CBtCOONa and CMCNa have complete biodegradability, good biocompatibility, excellent water solubility and easy scale-up preparation. Thus, these eco-friendly CPRTP materials with easy scale-up process and multi-responsive performance have great application prospects in information encryption, advanced anti-counterfeiting, and chiral recognition.Application of CPRTP materialsOwing to the excellent water solubility, processability and formability of anionic cellulose derivatives, the as-prepared CPRTP materials can be used as waterborne inks to directly prepare various anti-counterfeit phosphorescence patterns via inkjet printing and screen printing (Fig. 5). The L-CPRTP materials and R-CPRTP materials are printed in different regions to obtain complex anti-counterfeiting patterns. For example, a flower pattern consists of seven different R-CPRTP materials (Fig. 5a). Because their phosphorescence lifetime and time-dependence properties are different, the flower pattern exhibits a complex change as time increases. When a butterfly pattern is printed with L-CPRTP materials and R-CPRTP materials (Fig. 5a), it not only exhibits opposite CPL signals in different regions, but also shows diverse graphics as time extension and the change of excitation wavelengths. In addition, the CPRTP materials can exhibit dual functions of anti-counterfeiting and information encryption, based on their multi-responsive optical behaviors. We also printed a colorful number pattern of 2435 by using four kinds of CPRTP materials (Fig. 5b). As the excitation wavelength changes from 310 nm to 365 nm, the number 5 changes its fluorescence color, and the numbers of 2 and 3 exhibit a change on the phosphorescence color. Once the numbers are exposed to acidic gas, the phosphorescence of number 4 and 3 quenches, and the number 2 shows a change on its phosphorescence color. More importantly, the code information can be also hidden in this pattern. If the decode order is set as pH-nonresponsive numbers, L-CPRTP numbers and R-CPRTP numbers, the true digital code is 254523. These above examples indicate that the CPRTP materials have a huge potential in the advanced anti-counterfeiting and information encryption.Fig. 5: Application of CPRTP materials in anticounterfeiting and information encryption.a Phosphorescence photographs and CPL curve of anticounterfeiting patterns with different RTP inks. b Phosphorescence photographs and CPL curve of a numeric code for information encryption.
