Recycled Paper Gift Boxes: Three Categories of Actual Impurity Rates — The Three Key Figures and Three Response Scripts for Handling Printing Customers’ Concerns About “Paper Not Being White”

Why I Wrote This Article

In October 2025, the owners of three printing companies specializing in gift boxes contacted me one after another with similar complaints: “The first thing my customer said when they received this batch of recycled paper gift boxes was, ‘Why is it so gray?’” They then sent me screenshots of WeChat messages stating, “The paper isn’t white enough; we require virgin paper.” I put together the on-site product photos from all three factories, and this is the real “whiteness dilemma” encountered by printing companies in their recycled paper business—the visible “grayness” and the environmental claims on the certificates are two different things, and customers don’t understand this, while printing companies struggle to explain it.

How exactly does recycled paper end up “looking less white”? When explaining this to customers, 3 key figures cannot be avoided: the impurity rate of the pulp furnish, residual carbon after deinking, and brightness compensation. Depending on these 3 figures, the visual difference in the paper can range from “almost indistinguishable from virgin paper” to “noticeably gray with a yellow tint.” This article breaks the topic down according to these 3 figures, with each section followed by a customer-facing talking point that printing plants can genuinely use.

Number 1: Slurry Impurity Rate — the "Raw Material Purity" That Determines Recycled Paper Fiber Length

The impurity rate of recycled paper pulp (referred to as the "impurity rate") refers to the proportion of non-paper contaminants in recycled pulp, such as plastic, hot-melt adhesive, staples, ink residues, paraffin, wax-paper coatings, and asphalt. On the customer's final printed gift box paper, these contaminants manifest as 3 types of visual characteristics: 1) black spots (ink/asphalt residue); 2) raised particles (hot-melt adhesive/plastic); and 3) a waxy sheen (paraffin residue).

Situation regarding the mixing ratio of pulp sources used by 3 gift box printing plants:

Factory A (annual orders of 20 million, specializing in outer wrapping paper for baijiu gift boxes): Uses domestic mixed waste paper pulp from a recycled paper mill in Jiangsu, with an impurity rate of 1.8%. The finished gift boxes received by customers have 3-5 black spots or curled spots on the surface, making them visibly “dirty.” This factory’s return rate has reached 11% over the past 3 months, with customer complaints focused on “the surface does not look premium enough.”

Supplier B (50 million orders annually, primarily producing outer paper for beauty gift boxes): Uses imported North American waste paper pulp, with a contamination rate of 0.5%. The customer's finished products look virtually identical to those made with virgin pulp, but the unit price is 38% higher. This supplier's customers have a strong preference for "recycled paper" and are willing to accept a unit price premium.

Factory C (8 million orders annually, small-batch custom gift boxes): Uses domestically mixed waste paper pulp, with a reject rate of 2.3% and a whiteness of 78% ISO. When the customer received the finished product, they immediately said, “Isn’t this just ordinary paper?” This factory has the lowest unit price at 16 yuan per sheet, but customer acceptance is poor.

The comparison among the 3 factories clearly shows that a reject rate of 0.5% is the threshold for visible differences. Below 0.5%, it is difficult to distinguish the differences with the naked eye or from the original paper; above 1.5%, customer complaints that the “paper is not white or clean” begin to emerge.

Actual printing plant scenario script (Plant A): When Mr. Zhang, a baijiu client, visited the printing plant and saw the finished products, he challenged, “Why is this paper so gray?” Xiao Li from the printing plant did not directly explain the impurity rate. Instead, he said, “Mr. Zhang, for this batch of paper, we used domestic mixed recycled pulp from [Brand X], with an impurity rate of 1.8%. If you want a visual appearance closer to virgin paper, we have imported North American pulp from Plant B, with an impurity rate of 0.5%, at 38% higher cost. However, if what you are after is a gift positioning with a distinctly recycled feel, this batch is perfectly aligned with your product’s brand tone.” The client ultimately chose to continue using paper from Plant A, because his product was originally positioned around a “simple, artisanal brand tone.”

The core of this approach: rather than telling the customer that their aesthetic preferences are the issue, or that this is simply how the paper looks, it uses a three-part argument combining “shade variation figures,” “visual differences,” and “alignment with the product positioning” to guide the customer from the visual complaint that “the paper is not white enough” toward the strategic decision of whether the product is suitable for this type of paper.

Number 2: Deinking Residuals—Chemical Residues That Determine the “Grayness” of Recycled Paper

Residual carbon from deinking is the chemical reason recycled paper “looks gray.” When waste paper enters a recycling mill, it contains substantial amounts of ink and pigments, primarily carbon black. The deinking process washes these inks off the fibers. However, no deinking process can achieve 100% removal—the residual carbon black forms tiny black specks in the paper, affecting the whiteness of the finished product.

There is 1 quantitative indicator for deinking residual carbon: residual ink concentration (ERIC, Residual Ink Concentration), expressed in ppm (parts per million). ERIC and brightness have a rough correspondence table:

ERIC data from 3 factories:

Plant A: ERIC 65 ppm, brightness 86% ISO

Supplier B: ERIC 25 ppm, whiteness 91% ISO

Factory C: ERIC 120 ppm, whiteness 78% ISO

If you want to visually identify the differences in ERIC, there is a simple method: hold a sheet of recycled paper up against the light from a window. If you see small grayish-black spots in the paper fibers, this indicates a high ERIC value; if the entire sheet has a bluish-white appearance and the fibers are uniformly colored, this indicates a low ERIC value.

When a customer at the printing plant asks, “Why isn’t it white?”, if you have the ERIC data for this batch of paper, you can answer like this:

“Mr. Zhang, the ERIC value of this paper is 65 ppm, and its brightness is 86%. These figures meet the standard for mid-grade recycled paper—slightly greyer than imported recycled paper (ERIC 25, brightness 91%), but much better than domestically produced mixed recycled paper (ERIC 120, brightness 78%). If you want a brighter visual appearance, you can upgrade to imported pulp. If you want to control costs, you can enlarge the white areas and deepen the printing colors, using visual contrast to compensate for the paper’s greyness.”

The core of this sales script: “numbers + grades + solutions”. No showing off, no explanations; customers hear: “How many grades is this sheet? Why doesn’t it look white? How many options are there to make it whiter?”

Number 3: Whiteness Compensation—There Are Only 3 Remedies Available to Printing Plants

Whiteness compensation is something the printer can do during the finishing stage: if the ERIC of the raw material is already high, the printer can use process compensation to make the paper “look whiter.” Three common compensation methods:

Method 1: Add Optical Brightening Agents (OBA)

A fluorescent brightening agent is applied to the paper surface. After absorbing ultraviolet light, this substance emits blue-violet light, making the paper appear "whiter" to the human eye. However, OBA is a double-edged sword: 1) It is inexpensive; 2) paper whose whiteness has been compensated with OBA develops a bluish cast under daylight (and is not truly white); 3) its use in food packaging is restricted (it cannot come into direct contact with food).

OBA may be added to the outer paper of the baijiu gift box (which does not come into contact with food), but absolutely no OBA may be added to the liner paper. The printing plant must clearly distinguish between the outer and inner layers.

Method 2: Gray coverage with ink

If the customer's design features large areas of dark printing (dark blue/dark green/black/dark brown), the entire design can be darkened so that the paper's gray tone is concealed by the ink. After printing, the customer sees a "colored gift box" rather than "white paper." However, if the customer's design is "primarily white with areas of color," this compensation method is ineffective.

Method 3: Lamination for Dust Prevention

Apply a matte or gloss film to the surface of the finished gift box's outer paper. The film itself has an opacity of 80-90% and can conceal 60-70% of the paper's grayness. However, the laminated waste paper is difficult to recycle, reducing its environmental benefits—the printing plant must weigh the trade-offs.

In actual production, Factory A uses Method 2 (because the customer’s design features extensive dark-color printing), Factory B does not use compensation (as its slurry is already suitable), and Factory C once used Method 3 (lamination), but the customer reported that it “felt too much like plastic and did not look premium.” Factory C ultimately reverted to Method 2.

Printer’s Recommended Combination: When the order is signed, the printer proactively asks the customer: 1) Is it for the outer or inner layer of the gift box; 2) What is the main color of the design; 3) Whether lamination is acceptable. If all 3 questions are answered, the printer directly recommends the most suitable ink source + compensation method. This saves much more trouble than making remedial adjustments when the customer inspects the goods.

Solutions to the “Brightness Dilemma” in the Recycled Paper Business

After reviewing the real-world scenarios of 3 printing plants, the key to resolving the brightness dilemma is not “making the paper whiter,” but “aligning customers’ expectations with the paper’s positioning.” In terms of execution, printing plants can do 3 things:

First, proof prints before contract signing. Send the customer one A4 sample from each of 3 pulp sources for on-site selection. This is B Factory’s established practice, resulting in a low complaint rate.

Second, quantify the brightness value in the contract. Plant A revised the contract template, changing “white recycled paper” to “brightness 86%±2% ISO,” reducing the customer complaint rate from 11% to 3%.

Third, establish an in-house recycled paper sample library. The A factory store has sample boxes featuring 5 pulp sources, allowing customers visiting the factory to compare and select samples directly. This service enables customers to turn “brightness” from an abstract impression into a concrete choice.

For printing plants pursuing environmental initiatives, the customer's "environmental commitment" and "visual brightness" are two separate variables that require separate management. When a customer is willing to pay a 30% premium for environmentally friendly imported pulp, Plant B's solution is appropriate; when a customer has a tight budget but requires environmental claims, Plant A's solution is appropriate. By aligning these two variables, the brightness challenge no longer presents a dilemma.

Further Reading