This work investigates an inventory problem for deteriorating items with preservation technology investment, partial backlogged shortages, and trade credit. This model is considered for non-instantaneous deterioration (NID) items, where the deterioration of items begins after a certain storage period \((t_d)\) with a constant rate \((\theta )\) . Besides, to reduce the rate of deterioration, retailers invest money \((\xi )\) in preservation technology and to reduce the possibility of loss sellers provide partial trade credit to the buyers. Here, we consider two different scenarios: (i) seller provides fully trade credit to the buyers when the predefined quantity \((w)\) of the supplier is less than and equal to the order quantity \((Q)\) of the retailer; and (ii) seller provides the partial trade credit to the buyers when the order quantity is less than the predefined quantity. The main objective of this study is to reduce the total unit costs by determining the replenishment cycle-time, order quantity, and preservation technology cost. The aim of this study is to provide an insight into how preservation technology and credit financing can both be used to slow down the rate of deterioration and to provide flexible financing for consumers. The study not only provides insights to business managers to make proper management decisions but also helps them in considering the advantages and disadvantages of implementing preservation technology and credit financing. Some useful propositions, theorems, and lemmas are developed for finding the optimal solution analytically. Finally, numerical examples and managerial implications are incorporated to validate the proposed model.
